EXCLUSIVE USE AGREEMENT

         This Exclusive Use Agreement  (this  "Agreement") is entered into as of
the 1st day of  September,  1999  (the  "Effective  Date"),  by the  undersigned
shareholder  (the  "Equity  Holder") of Horizon  Vision  Center,  Inc., a Nevada
corporation  ("Horizon")  for the benefit of Horizon and Prime/BDR  Acquisition,
L.L.C., a Delaware limited  liability company ("Prime") and the parent companies
and affiliates of each of Horizon and Prime.

                                    RECITALS:

         WHEREAS, the Equity Holder is a shareholder of Horizon.

         WHEREAS,  the Equity  Holder is a physician or other  licensed  medical
professional.

         WHEREAS,   concurrently   with  the  execution  and  delivery  of  this
Agreement,  Prime and Horizon  are  consummating  that  certain  Stock  Purchase
Agreement (the "Stock Purchase Agreement"), dated September 1, 1999.

         WHEREAS,  in order to  induce  Horizon  and  Prime  to  consummate  the
transactions contemplated by the Stock Purchase Agreement, the Equity Holder has
agreed,  for a period of five (5)  years,  to  perform  all  Refractive  Surgery
Services (as defined  herein)  exclusively  at the  facilities of, and using the
equipment of, Horizon.

         THEREFORE, the parties hereto agree as follows:

                                   AGREEMENTS:

         1. Exclusive Use. Except as expressly  otherwise provided below, during
the term of this  Agreement,  the Equity Holder hereby agrees that,  without the
prior written consent of both Horizon and Prime, the Equity Holder will perform,
and will direct all other medically  trained or licensed  medical  professionals
under the  direction  or control of Equity  Holder to  perform,  all  Refractive
Surgery Services only at the facilities of, and using the equipment of, Horizon.
For purposes of this Agreement,  "Refractive Surgery Services" shall include all
refractive  surgery  modalities,  now or at any  time  during  the  term of this
Agreement performed,  offered or made available,  including, without limitation,
implantable   contact   lenses,   instromal   corneal  rings,   laser  in  situs
keratomileusis   photorefractive  keratectomy,   radial  keratotomy,   automated
lemellar   keratoplasty,   astigmatic  keratotomy  and  similar  or  replacement
procedures.

         Provided, however, that nothing in this Agreement shall be construed to
require Equity Holder to perform  Refractive  Surgery Services at the facilities
of, or use the equipment of, Horizon, if in Equity Holder's professional medical
judgment,  such use would be detrimental to Equity Holder's  patients.  Provided
further,  that this Agreement shall not apply to any Refractive Surgery Services
to be paid for, or reimbursed  by,  Medicare,  Medicaid,  Champus,  or any other
state or  federal  health  care  program,  or in any  other  instance  where the
operation of this Agreement would constitute a violation of applicable law.

         2.  Access.  Horizon  and Prime each agree that during the term of this
Agreement,  and for as long Equity  Holder  continues to meet the  credentialing
requirements of Horizon's  credentialing program as in effect from time to time,
Equity Holder shall be given access to Horizon's facilities, equipment and staff
in the same manner  such access has  generally  been  provided to Equity  Holder
prior to the date of this Agreement.

         3. Other Agreements.  Horizon and Prime each agree that during the term
of this  Agreement  and  for as long as  Equity  Holder  continues  to meet  the
credentialing  requirements of Horizon's credentialing program as in effect from
time to time,  Equity  Holder's  compensation  arrangement  will be  modified to
incorporate the terms of any  compensation  arrangement with any other physician
utilizing the  facilities,  equipment and staff,  to the extent such other terms
are substantially more favorable than the terms enjoyed by Equity Holder.

         4.  Allocation  of  Procedures.  Horizon  and  Prime  each  agree  that
inquiries  generated  by  Horizon  and not by a  particular  physician  shall be
distributed  among the  physician  shareholders  of  Horizon  (including  Equity
Holder) in a manner  consistent with the allocation  methods employed by Horizon
prior to the date of this  Agreement,  limited,  however,  in instances  where a
physician is not available to perform the procedure.

     5. Term. The term of this  Agreement  shall begin on the Effective Date and
shall continue for a period of five (5) years thereafter.

         6. Breach.  The Equity  Holder  agrees that a violation of any covenant
contained  in  Section 1 will  irreparably  damage  Horizon  and Prime for which
remedies at law may be  insufficient,  and for that  reason,  the Equity  Holder
further  agrees  that  Horizon  and Prime  shall each be entitled as a matter of
right to equitable  remedies,  including  specific  performance  and  injunctive
relief,  therefor. The right to specific performance and injunctive relief shall
be cumulative and in addition to whatever other  remedies,  at law or in equity,
that Horizon and Prime may have, including, specifically, recovery of additional
damages.

         7.       Miscellaneous.

               (a) Amendments. This Agreement may be modified or amended only by
          an instrument in writing executed by each of the parties hereto.

               (b) Headings.  The headings  contained in this  Agreement are for
          reference purposes only and shall not affect in any way the meaning or
          interpretation of this Agreement.

                  (c) Counterparts. This Agreement may be executed in any number
         of  counterparts,  each of which  shall be deemed an  original,  but in
         making proof hereof it shall not be necessary to produce or account for
         more than one such counterpart.

               (d) Governing Law. This Agreement shall be construed and enforced
          in accordance  with the internal  laws of the State of Texas,  and not
          the conflicts of law provisions thereof.

               (e) Parties Bound.  This  Agreement  shall be binding upon and be
          enforceable  against the Equity Holder.  This Agreement shall inure to
          the  benefit  of  Horizon,  Prime  and  their  respective  successors,
          representatives and assigns.

               (f) Assignment.  This Agreement and the rights granted  hereunder
          may not be assigned by Equity  Holder  without the written  consent of
          both Horizon and Prime.

                  (g)  Construction.  This Agreement shall be construed  without
         regard to the identity of the person who drafted the various provisions
         of this Agreement.  Each and every provision of this Agreement shall be
         construed  as though  all of the  parties  participated  equally in the
         drafting of this Agreement.  Consequently,  the parties acknowledge and
         agree that any rule of construction  that a document is to be construed
         against the drafting party shall not be applicable to this Agreement.

                  (h)  Severability.  This Agreement is intended to be performed
         in accordance with, and only to the extent permitted by, all applicable
         laws,  ordinances,  rules and  regulations.  If any  provision  of this
         Agreement,  or the application  thereof to any person or  circumstance,
         shall,  for any reason and to any extent,  be invalid or  unenforceable
         but the extent of the invalidity or  unenforceability  does not destroy
         the basis of the bargain between the parties as contained  herein,  the
         remainder of this  Agreement and the  application  of such provision to
         other  persons or  circumstances  shall not be  effected  thereby,  but
         rather shall be enforced to the fullest extent permitted by law.

                                                    [Signature page to follow]
                                                     -------------------------


<PAGE>

                                SIGNATURE PAGE TO

                             EXCLUSIVE USE AGREEMENT

         EXECUTED to be effective as of the date first above written.

EQUITY HOLDER:

                                   Signature: /s/ J. Robert Griffin, M.D.

                                   Printed Name: J. Robert Griffin

                                   Title:
                                   (if  signing  in  a representative capacity)



HORIZON:                           Horizon Vision Centers, Inc.

                                   Signature: /s/ David P. Bates III

                                   Printed Name: David P. Bates III

                                   Title: President



PRIME:                             Prime/BDR Acquisition, L.L.C.

                                   Signature: /s/ Cheryl Williams

                                   Printed Name: Cheryl Williams

                                   Title: Vice President

<PAGE>


                             EXCLUSIVE USE AGREEMENT

         This Exclusive Use Agreement  (this  "Agreement") is entered into as of
the 1st day of  September,  1999  (the  "Effective  Date"),  by the  undersigned
shareholder  (the  "Equity  Holder") of Horizon  Vision  Center,  Inc., a Nevada
corporation  ("Horizon")  for the benefit of Horizon and Prime/BDR  Acquisition,
L.L.C., a Delaware limited  liability company ("Prime") and the parent companies
and affiliates of each of Horizon and Prime.

                                    RECITALS:

         WHEREAS, the Equity Holder is a shareholder of Horizon.

         WHEREAS,  the Equity  Holder is a physician or other  licensed  medical
professional.

         WHEREAS,   concurrently   with  the  execution  and  delivery  of  this
Agreement,  Prime and Horizon  are  consummating  that  certain  Stock  Purchase
Agreement (the "Stock Purchase Agreement"), dated September 1, 1999.

         WHEREAS,  in order to  induce  Horizon  and  Prime  to  consummate  the
transactions contemplated by the Stock Purchase Agreement, the Equity Holder has
agreed,  for a period of five (5)  years,  to  perform  all  Refractive  Surgery
Services (as defined  herein)  exclusively  at the  facilities of, and using the
equipment of, Horizon.

         THEREFORE, the parties hereto agree as follows:

                                   AGREEMENTS:

         1. Exclusive Use. Except as expressly  otherwise provided below, during
the term of this  Agreement,  the Equity Holder hereby agrees that,  without the
prior written consent of both Horizon and Prime, the Equity Holder will perform,
and will direct all other medically  trained or licensed  medical  professionals
under the  direction  or control of Equity  Holder to  perform,  all  Refractive
Surgery Services only at the facilities of, and using the equipment of, Horizon.
For purposes of this Agreement,  "Refractive Surgery Services" shall include all
refractive  surgery  modalities,  now or at any  time  during  the  term of this
Agreement performed,  offered or made available,  including, without limitation,
implantable   contact   lenses,   instromal   corneal  rings,   laser  in  situs
keratomileusis   photorefractive  keratectomy,   radial  keratotomy,   automated
lemellar   keratoplasty,   astigmatic  keratotomy  and  similar  or  replacement
procedures.

         Provided, however, that nothing in this Agreement shall be construed to
require Equity Holder to perform  Refractive  Surgery Services at the facilities
of, or use the equipment of, Horizon, if in Equity Holder's professional medical
judgment,  such use would be detrimental to Equity Holder's  patients.  Provided
further,  that this Agreement shall not apply to any Refractive Surgery Services
to be paid for, or reimbursed  by,  Medicare,  Medicaid,  Champus,  or any other
state or  federal  health  care  program,  or in any  other  instance  where the
operation of this Agreement would constitute a violation of applicable law.

         2.  Access.  Horizon  and Prime each agree that during the term of this
Agreement,  and for as long Equity  Holder  continues to meet the  credentialing
requirements of Horizon's  credentialing program as in effect from time to time,
Equity Holder shall be given access to Horizon's facilities, equipment and staff
in the same manner  such access has  generally  been  provided to Equity  Holder
prior to the date of this Agreement.

         3. Other Agreements.  Horizon and Prime each agree that during the term
of this  Agreement  and  for as long as  Equity  Holder  continues  to meet  the
credentialing  requirements of Horizon's credentialing program as in effect from
time to time,  Equity  Holder's  compensation  arrangement  will be  modified to
incorporate the terms of any  compensation  arrangement with any other physician
utilizing the  facilities,  equipment and staff,  to the extent such other terms
are substantially more favorable than the terms enjoyed by Equity Holder.

         4.  Allocation  of  Procedures.  Horizon  and  Prime  each  agree  that
inquiries  generated  by  Horizon  and not by a  particular  physician  shall be
distributed  among the  physician  shareholders  of  Horizon  (including  Equity
Holder) in a manner  consistent with the allocation  methods employed by Horizon
prior to the date of this  Agreement,  limited,  however,  in instances  where a
physician is not available to perform the procedure.

     5. Term. The term of this  Agreement  shall begin on the Effective Date and
shall continue for a period of five (5) years thereafter.

         6. Breach.  The Equity  Holder  agrees that a violation of any covenant
contained  in  Section 1 will  irreparably  damage  Horizon  and Prime for which
remedies at law may be  insufficient,  and for that  reason,  the Equity  Holder
further  agrees  that  Horizon  and Prime  shall each be entitled as a matter of
right to equitable  remedies,  including  specific  performance  and  injunctive
relief,  therefor. The right to specific performance and injunctive relief shall
be cumulative and in addition to whatever other  remedies,  at law or in equity,
that Horizon and Prime may have, including, specifically, recovery of additional
damages.

         7.       Miscellaneous.

               (a) Amendments. This Agreement may be modified or amended only by
          an instrument in writing executed by each of the parties hereto.

               (b) Headings.  The headings  contained in this  Agreement are for
          reference purposes only and shall not affect in any way the meaning or
          interpretation of this Agreement.

                  (c) Counterparts. This Agreement may be executed in any number
         of  counterparts,  each of which  shall be deemed an  original,  but in
         making proof hereof it shall not be necessary to produce or account for
         more than one such counterpart.

               (d) Governing Law. This Agreement shall be construed and enforced
          in accordance  with the internal  laws of the State of Texas,  and not
          the conflicts of law provisions thereof.

               (e) Parties Bound.  This  Agreement  shall be binding upon and be
          enforceable  against the Equity Holder.  This Agreement shall inure to
          the  benefit  of  Horizon,  Prime  and  their  respective  successors,
          representatives and assigns.

               (f) Assignment.  This Agreement and the rights granted  hereunder
          may not be assigned by Equity  Holder  without the written  consent of
          both Horizon and Prime.

                  (g)  Construction.  This Agreement shall be construed  without
         regard to the identity of the person who drafted the various provisions
         of this Agreement.  Each and every provision of this Agreement shall be
         construed  as though  all of the  parties  participated  equally in the
         drafting of this Agreement.  Consequently,  the parties acknowledge and
         agree that any rule of construction  that a document is to be construed
         against the drafting party shall not be applicable to this Agreement.

                  (h)  Severability.  This Agreement is intended to be performed
         in accordance with, and only to the extent permitted by, all applicable
         laws,  ordinances,  rules and  regulations.  If any  provision  of this
         Agreement,  or the application  thereof to any person or  circumstance,
         shall,  for any reason and to any extent,  be invalid or  unenforceable
         but the extent of the invalidity or  unenforceability  does not destroy
         the basis of the bargain between the parties as contained  herein,  the
         remainder of this  Agreement and the  application  of such provision to
         other  persons or  circumstances  shall not be  effected  thereby,  but
         rather shall be enforced to the fullest extent permitted by law.

                                                    [Signature page to follow]
                                                     -------------------------


<PAGE>
                                SIGNATURE PAGE TO

                             EXCLUSIVE USE AGREEMENT

         EXECUTED to be effective as of the date first above written.

EQUITY HOLDER:
                                   Signature: /s/ Christian S. Kim, M.D.

                                   Printed Name: Christian S. Kim, M.D.

                                   Title:
                                   (if  signing  in  a representative capacity)



HORIZON:                           Horizon Vision Centers, Inc.

                                   Signature: /s/ David Bates

                                   Printed Name: David Bates

                                   Title: President



PRIME:                             Prime/BDR Acquisition, L.L.C.

                                   Signature: /s/ Cheryl Williams

                                   Printed Name:Cheryl Williams

                                   Title: Vice President


<PAGE>

                             EXCLUSIVE USE AGREEMENT

         This Exclusive Use Agreement  (this  "Agreement") is entered into as of
the 1st day of  September,  1999  (the  "Effective  Date"),  by the  undersigned
shareholder  (the  "Equity  Holder") of Horizon  Vision  Center,  Inc., a Nevada
corporation  ("Horizon")  for the benefit of Horizon and Prime/BDR  Acquisition,
L.L.C., a Delaware limited  liability company ("Prime") and the parent companies
and affiliates of each of Horizon and Prime.

                                    RECITALS:

         WHEREAS, the Equity Holder is a shareholder of Horizon.

         WHEREAS,  the Equity  Holder is a physician or other  licensed  medical
professional.

         WHEREAS,   concurrently   with  the  execution  and  delivery  of  this
Agreement,  Prime and Horizon  are  consummating  that  certain  Stock  Purchase
Agreement (the "Stock Purchase Agreement"), dated September 1, 1999.

         WHEREAS,  in order to  induce  Horizon  and  Prime  to  consummate  the
transactions contemplated by the Stock Purchase Agreement, the Equity Holder has
agreed,  for a period of five (5)  years,  to  perform  all  Refractive  Surgery
Services (as defined  herein)  exclusively  at the  facilities of, and using the
equipment of, Horizon.

         THEREFORE, the parties hereto agree as follows:

                                   AGREEMENTS:

         1. Exclusive Use. Except as expressly  otherwise provided below, during
the term of this  Agreement,  the Equity Holder hereby agrees that,  without the
prior written consent of both Horizon and Prime, the Equity Holder will perform,
and will direct all other medically  trained or licensed  medical  professionals
under the  direction  or control of Equity  Holder to  perform,  all  Refractive
Surgery Services only at the facilities of, and using the equipment of, Horizon.
For purposes of this Agreement,  "Refractive Surgery Services" shall include all
refractive  surgery  modalities,  now or at any  time  during  the  term of this
Agreement performed,  offered or made available,  including, without limitation,
implantable   contact   lenses,   instromal   corneal  rings,   laser  in  situs
keratomileusis   photorefractive  keratectomy,   radial  keratotomy,   automated
lemellar   keratoplasty,   astigmatic  keratotomy  and  similar  or  replacement
procedures.

         Provided, however, that nothing in this Agreement shall be construed to
require Equity Holder to perform  Refractive  Surgery Services at the facilities
of, or use the equipment of, Horizon, if in Equity Holder's professional medical
judgment,  such use would be detrimental to Equity Holder's  patients.  Provided
further,  that this Agreement shall not apply to any Refractive Surgery Services
to be paid for, or reimbursed  by,  Medicare,  Medicaid,  Champus,  or any other
state or  federal  health  care  program,  or in any  other  instance  where the
operation of this Agreement would constitute a violation of applicable law.

         2.  Access.  Horizon  and Prime each agree that during the term of this
Agreement,  and for as long Equity  Holder  continues to meet the  credentialing
requirements of Horizon's  credentialing program as in effect from time to time,
Equity Holder shall be given access to Horizon's facilities, equipment and staff
in the same manner  such access has  generally  been  provided to Equity  Holder
prior to the date of this Agreement.

         3. Other Agreements.  Horizon and Prime each agree that during the term
of this  Agreement  and  for as long as  Equity  Holder  continues  to meet  the
credentialing  requirements of Horizon's credentialing program as in effect from
time to time,  Equity  Holder's  compensation  arrangement  will be  modified to
incorporate the terms of any  compensation  arrangement with any other physician
utilizing the  facilities,  equipment and staff,  to the extent such other terms
are substantially more favorable than the terms enjoyed by Equity Holder.

         4.  Allocation  of  Procedures.  Horizon  and  Prime  each  agree  that
inquiries  generated  by  Horizon  and not by a  particular  physician  shall be
distributed  among the  physician  shareholders  of  Horizon  (including  Equity
Holder) in a manner  consistent with the allocation  methods employed by Horizon
prior to the date of this  Agreement,  limited,  however,  in instances  where a
physician is not available to perform the procedure.

     5. Term. The term of this  Agreement  shall begin on the Effective Date and
shall continue for a period of five (5) years thereafter.

         6. Breach.  The Equity  Holder  agrees that a violation of any covenant
contained  in  Section 1 will  irreparably  damage  Horizon  and Prime for which
remedies at law may be  insufficient,  and for that  reason,  the Equity  Holder
further  agrees  that  Horizon  and Prime  shall each be entitled as a matter of
right to equitable  remedies,  including  specific  performance  and  injunctive
relief,  therefor. The right to specific performance and injunctive relief shall
be cumulative and in addition to whatever other  remedies,  at law or in equity,
that Horizon and Prime may have, including, specifically, recovery of additional
damages.

         7.       Miscellaneous.

               (a) Amendments. This Agreement may be modified or amended only by
          an instrument in writing executed by each of the parties hereto.

               (b) Headings.  The headings  contained in this  Agreement are for
          reference purposes only and shall not affect in any way the meaning or
          interpretation of this Agreement.

                  (c) Counterparts. This Agreement may be executed in any number
         of  counterparts,  each of which  shall be deemed an  original,  but in
         making proof hereof it shall not be necessary to produce or account for
         more than one such counterpart.

               (d) Governing Law. This Agreement shall be construed and enforced
          in accordance  with the internal  laws of the State of Texas,  and not
          the conflicts of law provisions thereof.

               (e) Parties Bound.  This  Agreement  shall be binding upon and be
          enforceable  against the Equity Holder.  This Agreement shall inure to
          the  benefit  of  Horizon,  Prime  and  their  respective  successors,
          representatives and assigns.

               (f) Assignment.  This Agreement and the rights granted  hereunder
          may not be assigned by Equity  Holder  without the written  consent of
          both Horizon and Prime.

                  (g)  Construction.  This Agreement shall be construed  without
         regard to the identity of the person who drafted the various provisions
         of this Agreement.  Each and every provision of this Agreement shall be
         construed  as though  all of the  parties  participated  equally in the
         drafting of this Agreement.  Consequently,  the parties acknowledge and
         agree that any rule of construction  that a document is to be construed
         against the drafting party shall not be applicable to this Agreement.

                  (h)  Severability.  This Agreement is intended to be performed
         in accordance with, and only to the extent permitted by, all applicable
         laws,  ordinances,  rules and  regulations.  If any  provision  of this
         Agreement,  or the application  thereof to any person or  circumstance,
         shall,  for any reason and to any extent,  be invalid or  unenforceable
         but the extent of the invalidity or  unenforceability  does not destroy
         the basis of the bargain between the parties as contained  herein,  the
         remainder of this  Agreement and the  application  of such provision to
         other  persons or  circumstances  shall not be  effected  thereby,  but
         rather shall be enforced to the fullest extent permitted by law.

                                                    [Signature page to follow]
                                                     -------------------------


<PAGE>


                                SIGNATURE PAGE TO

                             EXCLUSIVE USE AGREEMENT

         EXECUTED to be effective as of the date first above written.

EQUITY HOLDER:
                                   Signature: /s/ Mark R. Mandel, M.D.

                                   Printed Name: Mark R. Mandel, M.D.

                                   Title:
                                   (if  signing  in  a representative capacity)



HORIZON:                           Horizon Vision Centers, Inc.

                                   Signature: /s/ David Bates

                                   Printed Name: David Bates

                                   Title: President



PRIME:                             Prime/BDR Acquisition, L.L.C.

                                   Signature: /s/ Cheryl Williams

                                   Printed Name:Cheryl Williams

                                   Title: Vice President
<PAGE>


                             EXCLUSIVE USE AGREEMENT

         This Exclusive Use Agreement  (this  "Agreement") is entered into as of
the 1st day of  September,  1999  (the  "Effective  Date"),  by the  undersigned
shareholder  (the  "Equity  Holder") of Horizon  Vision  Center,  Inc., a Nevada
corporation  ("Horizon")  for the benefit of Horizon and Prime/BDR  Acquisition,
L.L.C., a Delaware limited  liability company ("Prime") and the parent companies
and affiliates of each of Horizon and Prime.

                                    RECITALS:

         WHEREAS, the Equity Holder is a shareholder of Horizon.

         WHEREAS,  the Equity  Holder is a physician or other  licensed  medical
professional.

         WHEREAS,   concurrently   with  the  execution  and  delivery  of  this
Agreement,  Prime and Horizon  are  consummating  that  certain  Stock  Purchase
Agreement (the "Stock Purchase Agreement"), dated September 1, 1999.

         WHEREAS,  in order to  induce  Horizon  and  Prime  to  consummate  the
transactions contemplated by the Stock Purchase Agreement, the Equity Holder has
agreed,  for a period of five (5)  years,  to  perform  all  Refractive  Surgery
Services (as defined  herein)  exclusively  at the  facilities of, and using the
equipment of, Horizon.

         THEREFORE, the parties hereto agree as follows:

                                   AGREEMENTS:

         1. Exclusive Use. Except as expressly  otherwise provided below, during
the term of this  Agreement,  the Equity Holder hereby agrees that,  without the
prior written consent of both Horizon and Prime, the Equity Holder will perform,
and will direct all other medically  trained or licensed  medical  professionals
under the  direction  or control of Equity  Holder to  perform,  all  Refractive
Surgery Services only at the facilities of, and using the equipment of, Horizon.
For purposes of this Agreement,  "Refractive Surgery Services" shall include all
refractive  surgery  modalities,  now or at any  time  during  the  term of this
Agreement performed,  offered or made available,  including, without limitation,
implantable   contact   lenses,   instromal   corneal  rings,   laser  in  situs
keratomileusis   photorefractive  keratectomy,   radial  keratotomy,   automated
lemellar   keratoplasty,   astigmatic  keratotomy  and  similar  or  replacement
procedures.

         Provided, however, that nothing in this Agreement shall be construed to
require Equity Holder to perform  Refractive  Surgery Services at the facilities
of, or use the equipment of, Horizon, if in Equity Holder's professional medical
judgment,  such use would be detrimental to Equity Holder's  patients.  Provided
further,  that this Agreement shall not apply to any Refractive Surgery Services
to be paid for, or reimbursed  by,  Medicare,  Medicaid,  Champus,  or any other
state or  federal  health  care  program,  or in any  other  instance  where the
operation of this Agreement would constitute a violation of applicable law.

         2.  Access.  Horizon  and Prime each agree that during the term of this
Agreement,  and for as long Equity  Holder  continues to meet the  credentialing
requirements of Horizon's  credentialing program as in effect from time to time,
Equity Holder shall be given access to Horizon's facilities, equipment and staff
in the same manner  such access has  generally  been  provided to Equity  Holder
prior to the date of this Agreement.

         3. Other Agreements.  Horizon and Prime each agree that during the term
of this  Agreement  and  for as long as  Equity  Holder  continues  to meet  the
credentialing  requirements of Horizon's credentialing program as in effect from
time to time,  Equity  Holder's  compensation  arrangement  will be  modified to
incorporate the terms of any  compensation  arrangement with any other physician
utilizing the  facilities,  equipment and staff,  to the extent such other terms
are substantially more favorable than the terms enjoyed by Equity Holder.

         4.  Allocation  of  Procedures.  Horizon  and  Prime  each  agree  that
inquiries  generated  by  Horizon  and not by a  particular  physician  shall be
distributed  among the  physician  shareholders  of  Horizon  (including  Equity
Holder) in a manner  consistent with the allocation  methods employed by Horizon
prior to the date of this  Agreement,  limited,  however,  in instances  where a
physician is not available to perform the procedure.

     5. Term. The term of this  Agreement  shall begin on the Effective Date and
shall continue for a period of five (5) years thereafter.

         6. Breach.  The Equity  Holder  agrees that a violation of any covenant
contained  in  Section 1 will  irreparably  damage  Horizon  and Prime for which
remedies at law may be  insufficient,  and for that  reason,  the Equity  Holder
further  agrees  that  Horizon  and Prime  shall each be entitled as a matter of
right to equitable  remedies,  including  specific  performance  and  injunctive
relief,  therefor. The right to specific performance and injunctive relief shall
be cumulative and in addition to whatever other  remedies,  at law or in equity,
that Horizon and Prime may have, including, specifically, recovery of additional
damages.

         7.       Miscellaneous.

               (a) Amendments. This Agreement may be modified or amended only by
          an instrument in writing executed by each of the parties hereto.

               (b) Headings.  The headings  contained in this  Agreement are for
          reference purposes only and shall not affect in any way the meaning or
          interpretation of this Agreement.

                  (c) Counterparts. This Agreement may be executed in any number
         of  counterparts,  each of which  shall be deemed an  original,  but in
         making proof hereof it shall not be necessary to produce or account for
         more than one such counterpart.

               (d) Governing Law. This Agreement shall be construed and enforced
          in accordance  with the internal  laws of the State of Texas,  and not
          the conflicts of law provisions thereof.

               (e) Parties Bound.  This  Agreement  shall be binding upon and be
          enforceable  against the Equity Holder.  This Agreement shall inure to
          the  benefit  of  Horizon,  Prime  and  their  respective  successors,
          representatives and assigns.

               (f) Assignment.  This Agreement and the rights granted  hereunder
          may not be assigned by Equity  Holder  without the written  consent of
          both Horizon and Prime.

                  (g)  Construction.  This Agreement shall be construed  without
         regard to the identity of the person who drafted the various provisions
         of this Agreement.  Each and every provision of this Agreement shall be
         construed  as though  all of the  parties  participated  equally in the
         drafting of this Agreement.  Consequently,  the parties acknowledge and
         agree that any rule of construction  that a document is to be construed
         against the drafting party shall not be applicable to this Agreement.

                  (h)  Severability.  This Agreement is intended to be performed
         in accordance with, and only to the extent permitted by, all applicable
         laws,  ordinances,  rules and  regulations.  If any  provision  of this
         Agreement,  or the application  thereof to any person or  circumstance,
         shall,  for any reason and to any extent,  be invalid or  unenforceable
         but the extent of the invalidity or  unenforceability  does not destroy
         the basis of the bargain between the parties as contained  herein,  the
         remainder of this  Agreement and the  application  of such provision to
         other  persons or  circumstances  shall not be  effected  thereby,  but
         rather shall be enforced to the fullest extent permitted by law.

                                                    [Signature page to follow]
                                                     -------------------------


<PAGE>
                                SIGNATURE PAGE TO

                             EXCLUSIVE USE AGREEMENT

         EXECUTED to be effective as of the date first above written.

EQUITY HOLDER:

                                   Signature: /s/ D. Brent Reed, M.D.

                                   Printed Name: D. Brent Reed, M.D.

                                   Title:
                                   (if  signing  in  a representative capacity)



HORIZON:                           Horizon Vision Centers, Inc.

                                   Signature: /s/ David Bates

                                   Printed Name: David Bates

                                   Title: President



PRIME:                             Prime/BDR Acquisition, L.L.C.

                                   Signature: /s/ Cheryl Williams

                                   Printed Name: Cheryl Williams

                                   Title: Vice President


<PAGE>

                             EXCLUSIVE USE AGREEMENT

         This Exclusive Use Agreement  (this  "Agreement") is entered into as of
the 1st day of  September,  1999  (the  "Effective  Date"),  by the  undersigned
shareholder  (the  "Equity  Holder") of Horizon  Vision  Center,  Inc., a Nevada
corporation  ("Horizon")  for the benefit of Horizon and Prime/BDR  Acquisition,
L.L.C., a Delaware limited  liability company ("Prime") and the parent companies
and affiliates of each of Horizon and Prime.

                                    RECITALS:

         WHEREAS, the Equity Holder is a shareholder of Horizon.

         WHEREAS,  the Equity  Holder is a physician or other  licensed  medical
professional.

         WHEREAS,   concurrently   with  the  execution  and  delivery  of  this
Agreement,  Prime and Horizon  are  consummating  that  certain  Stock  Purchase
Agreement (the "Stock Purchase Agreement"), dated September 1, 1999.

         WHEREAS,  in order to  induce  Horizon  and  Prime  to  consummate  the
transactions contemplated by the Stock Purchase Agreement, the Equity Holder has
agreed,  for a period of five (5)  years,  to  perform  all  Refractive  Surgery
Services (as defined  herein)  exclusively  at the  facilities of, and using the
equipment of, Horizon.

         THEREFORE, the parties hereto agree as follows:

                                   AGREEMENTS:

         1. Exclusive Use. Except as expressly  otherwise provided below, during
the term of this  Agreement,  the Equity Holder hereby agrees that,  without the
prior written consent of both Horizon and Prime, the Equity Holder will perform,
and will direct all other medically  trained or licensed  medical  professionals
under the  direction  or control of Equity  Holder to  perform,  all  Refractive
Surgery Services only at the facilities of, and using the equipment of, Horizon.
For purposes of this Agreement,  "Refractive Surgery Services" shall include all
refractive  surgery  modalities,  now or at any  time  during  the  term of this
Agreement performed,  offered or made available,  including, without limitation,
implantable   contact   lenses,   instromal   corneal  rings,   laser  in  situs
keratomileusis   photorefractive  keratectomy,   radial  keratotomy,   automated
lemellar   keratoplasty,   astigmatic  keratotomy  and  similar  or  replacement
procedures.

         Provided, however, that nothing in this Agreement shall be construed to
require Equity Holder to perform  Refractive  Surgery Services at the facilities
of, or use the equipment of, Horizon, if in Equity Holder's professional medical
judgment,  such use would be detrimental to Equity Holder's  patients.  Provided
further,  that this Agreement shall not apply to any Refractive Surgery Services
to be paid for, or reimbursed  by,  Medicare,  Medicaid,  Champus,  or any other
state or  federal  health  care  program,  or in any  other  instance  where the
operation of this Agreement would constitute a violation of applicable law.

         2.  Access.  Horizon  and Prime each agree that during the term of this
Agreement,  and for as long Equity  Holder  continues to meet the  credentialing
requirements of Horizon's  credentialing program as in effect from time to time,
Equity Holder shall be given access to Horizon's facilities, equipment and staff
in the same manner  such access has  generally  been  provided to Equity  Holder
prior to the date of this Agreement.

         3. Other Agreements.  Horizon and Prime each agree that during the term
of this  Agreement  and  for as long as  Equity  Holder  continues  to meet  the
credentialing  requirements of Horizon's credentialing program as in effect from
time to time,  Equity  Holder's  compensation  arrangement  will be  modified to
incorporate the terms of any  compensation  arrangement with any other physician
utilizing the  facilities,  equipment and staff,  to the extent such other terms
are substantially more favorable than the terms enjoyed by Equity Holder.

         4.  Allocation  of  Procedures.  Horizon  and  Prime  each  agree  that
inquiries  generated  by  Horizon  and not by a  particular  physician  shall be
distributed  among the  physician  shareholders  of  Horizon  (including  Equity
Holder) in a manner  consistent with the allocation  methods employed by Horizon
prior to the date of this  Agreement,  limited,  however,  in instances  where a
physician is not available to perform the procedure.

     5. Term. The term of this  Agreement  shall begin on the Effective Date and
shall continue for a period of five (5) years thereafter.

         6. Breach.  The Equity  Holder  agrees that a violation of any covenant
contained  in  Section 1 will  irreparably  damage  Horizon  and Prime for which
remedies at law may be  insufficient,  and for that  reason,  the Equity  Holder
further  agrees  that  Horizon  and Prime  shall each be entitled as a matter of
right to equitable  remedies,  including  specific  performance  and  injunctive
relief,  therefor. The right to specific performance and injunctive relief shall
be cumulative and in addition to whatever other  remedies,  at law or in equity,
that Horizon and Prime may have, including, specifically, recovery of additional
damages.

         7.       Miscellaneous.

               (a) Amendments. This Agreement may be modified or amended only by
          an instrument in writing executed by each of the parties hereto.

               (b) Headings.  The headings  contained in this  Agreement are for
          reference purposes only and shall not affect in any way the meaning or
          interpretation of this Agreement.

                  (c) Counterparts. This Agreement may be executed in any number
         of  counterparts,  each of which  shall be deemed an  original,  but in
         making proof hereof it shall not be necessary to produce or account for
         more than one such counterpart.

               (d) Governing Law. This Agreement shall be construed and enforced
          in accordance  with the internal  laws of the State of Texas,  and not
          the conflicts of law provisions thereof.

               (e) Parties Bound.  This  Agreement  shall be binding upon and be
          enforceable  against the Equity Holder.  This Agreement shall inure to
          the  benefit  of  Horizon,  Prime  and  their  respective  successors,
          representatives and assigns.

               (f) Assignment.  This Agreement and the rights granted  hereunder
          may not be assigned by Equity  Holder  without the written  consent of
          both Horizon and Prime.

                  (g)  Construction.  This Agreement shall be construed  without
         regard to the identity of the person who drafted the various provisions
         of this Agreement.  Each and every provision of this Agreement shall be
         construed  as though  all of the  parties  participated  equally in the
         drafting of this Agreement.  Consequently,  the parties acknowledge and
         agree that any rule of construction  that a document is to be construed
         against the drafting party shall not be applicable to this Agreement.

                  (h)  Severability.  This Agreement is intended to be performed
         in accordance with, and only to the extent permitted by, all applicable
         laws,  ordinances,  rules and  regulations.  If any  provision  of this
         Agreement,  or the application  thereof to any person or  circumstance,
         shall,  for any reason and to any extent,  be invalid or  unenforceable
         but the extent of the invalidity or  unenforceability  does not destroy
         the basis of the bargain between the parties as contained  herein,  the
         remainder of this  Agreement and the  application  of such provision to
         other  persons or  circumstances  shall not be  effected  thereby,  but
         rather shall be enforced to the fullest extent permitted by law.

                                                    [Signature page to follow]
                                                     -------------------------


<PAGE>
                                SIGNATURE PAGE TO

                             EXCLUSIVE USE AGREEMENT

         EXECUTED to be effective as of the date first above written.

EQUITY HOLDER:

                                   Signature: /s/ Bradley J. Sandler, M.D.

                                   Printed Name: Bradley J. Sandler, M.D.

                                   Title:
                                   (if  signing  in  a representative capacity)



HORIZON:                           Horizon Vision Centers, Inc.

                                   Signature: /s/ David Bates

                                   Printed Name: David Bates

                                   Title: President



PRIME:                             Prime/BDR Acquisition, L.L.C.

                                   Signature: /s/ Cheryl Williams

                                   Printed Name: Cheryl Williams

                                   Title: Vice President


<PAGE>

                             EXCLUSIVE USE AGREEMENT

         This Exclusive Use Agreement  (this  "Agreement") is entered into as of
the 1st day of  September,  1999  (the  "Effective  Date"),  by the  undersigned
shareholder  (the  "Equity  Holder") of Horizon  Vision  Center,  Inc., a Nevada
corporation  ("Horizon")  for the benefit of Horizon and Prime/BDR  Acquisition,
L.L.C., a Delaware limited  liability company ("Prime") and the parent companies
and affiliates of each of Horizon and Prime.

                                    RECITALS:

         WHEREAS, the Equity Holder is a shareholder of Horizon.

         WHEREAS,  the Equity  Holder is a physician or other  licensed  medical
professional.

         WHEREAS,   concurrently   with  the  execution  and  delivery  of  this
Agreement,  Prime and Horizon  are  consummating  that  certain  Stock  Purchase
Agreement (the "Stock Purchase Agreement"), dated September 1, 1999.

         WHEREAS,  in order to  induce  Horizon  and  Prime  to  consummate  the
transactions contemplated by the Stock Purchase Agreement, the Equity Holder has
agreed,  for a period of five (5)  years,  to  perform  all  Refractive  Surgery
Services (as defined  herein)  exclusively  at the  facilities of, and using the
equipment of, Horizon.

         THEREFORE, the parties hereto agree as follows:

                                   AGREEMENTS:

         1. Exclusive Use. Except as expressly  otherwise provided below, during
the term of this  Agreement,  the Equity Holder hereby agrees that,  without the
prior written consent of both Horizon and Prime, the Equity Holder will perform,
and will direct all other medically  trained or licensed  medical  professionals
under the  direction  or control of Equity  Holder to  perform,  all  Refractive
Surgery Services only at the facilities of, and using the equipment of, Horizon.
For purposes of this Agreement,  "Refractive Surgery Services" shall include all
refractive  surgery  modalities,  now or at any  time  during  the  term of this
Agreement performed,  offered or made available,  including, without limitation,
implantable   contact   lenses,   instromal   corneal  rings,   laser  in  situs
keratomileusis   photorefractive  keratectomy,   radial  keratotomy,   automated
lemellar   keratoplasty,   astigmatic  keratotomy  and  similar  or  replacement
procedures.

         Provided, however, that nothing in this Agreement shall be construed to
require Equity Holder to perform  Refractive  Surgery Services at the facilities
of, or use the equipment of, Horizon, if in Equity Holder's professional medical
judgment,  such use would be detrimental to Equity Holder's  patients.  Provided
further,  that this Agreement shall not apply to any Refractive Surgery Services
to be paid for, or reimbursed  by,  Medicare,  Medicaid,  Champus,  or any other
state or  federal  health  care  program,  or in any  other  instance  where the
operation of this Agreement would constitute a violation of applicable law.

         2.  Access.  Horizon  and Prime each agree that during the term of this
Agreement,  and for as long Equity  Holder  continues to meet the  credentialing
requirements of Horizon's  credentialing program as in effect from time to time,
Equity Holder shall be given access to Horizon's facilities, equipment and staff
in the same manner  such access has  generally  been  provided to Equity  Holder
prior to the date of this Agreement.

         3. Other Agreements.  Horizon and Prime each agree that during the term
of this  Agreement  and  for as long as  Equity  Holder  continues  to meet  the
credentialing  requirements of Horizon's credentialing program as in effect from
time to time,  Equity  Holder's  compensation  arrangement  will be  modified to
incorporate the terms of any  compensation  arrangement with any other physician
utilizing the  facilities,  equipment and staff,  to the extent such other terms
are substantially more favorable than the terms enjoyed by Equity Holder.

         4.  Allocation  of  Procedures.  Horizon  and  Prime  each  agree  that
inquiries  generated  by  Horizon  and not by a  particular  physician  shall be
distributed  among the  physician  shareholders  of  Horizon  (including  Equity
Holder) in a manner  consistent with the allocation  methods employed by Horizon
prior to the date of this  Agreement,  limited,  however,  in instances  where a
physician is not available to perform the procedure.

     5. Term. The term of this  Agreement  shall begin on the Effective Date and
shall continue for a period of five (5) years thereafter.

         6. Breach.  The Equity  Holder  agrees that a violation of any covenant
contained  in  Section 1 will  irreparably  damage  Horizon  and Prime for which
remedies at law may be  insufficient,  and for that  reason,  the Equity  Holder
further  agrees  that  Horizon  and Prime  shall each be entitled as a matter of
right to equitable  remedies,  including  specific  performance  and  injunctive
relief,  therefor. The right to specific performance and injunctive relief shall
be cumulative and in addition to whatever other  remedies,  at law or in equity,
that Horizon and Prime may have, including, specifically, recovery of additional
damages.

         7.       Miscellaneous.

               (a) Amendments. This Agreement may be modified or amended only by
          an instrument in writing executed by each of the parties hereto.

               (b) Headings.  The headings  contained in this  Agreement are for
          reference purposes only and shall not affect in any way the meaning or
          interpretation of this Agreement.

                  (c) Counterparts. This Agreement may be executed in any number
         of  counterparts,  each of which  shall be deemed an  original,  but in
         making proof hereof it shall not be necessary to produce or account for
         more than one such counterpart.

               (d) Governing Law. This Agreement shall be construed and enforced
          in accordance  with the internal  laws of the State of Texas,  and not
          the conflicts of law provisions thereof.

               (e) Parties Bound.  This  Agreement  shall be binding upon and be
          enforceable  against the Equity Holder.  This Agreement shall inure to
          the  benefit  of  Horizon,  Prime  and  their  respective  successors,
          representatives and assigns.

               (f) Assignment.  This Agreement and the rights granted  hereunder
          may not be assigned by Equity  Holder  without the written  consent of
          both Horizon and Prime.

                  (g)  Construction.  This Agreement shall be construed  without
         regard to the identity of the person who drafted the various provisions
         of this Agreement.  Each and every provision of this Agreement shall be
         construed  as though  all of the  parties  participated  equally in the
         drafting of this Agreement.  Consequently,  the parties acknowledge and
         agree that any rule of construction  that a document is to be construed
         against the drafting party shall not be applicable to this Agreement.

                  (h)  Severability.  This Agreement is intended to be performed
         in accordance with, and only to the extent permitted by, all applicable
         laws,  ordinances,  rules and  regulations.  If any  provision  of this
         Agreement,  or the application  thereof to any person or  circumstance,
         shall,  for any reason and to any extent,  be invalid or  unenforceable
         but the extent of the invalidity or  unenforceability  does not destroy
         the basis of the bargain between the parties as contained  herein,  the
         remainder of this  Agreement and the  application  of such provision to
         other  persons or  circumstances  shall not be  effected  thereby,  but
         rather shall be enforced to the fullest extent permitted by law.

                                                    [Signature page to follow]
                                                     -------------------------


<PAGE>

                                SIGNATURE PAGE TO

                             EXCLUSIVE USE AGREEMENT

         EXECUTED to be effective as of the date first above written.

EQUITY HOLDER:

                                   Signature: /s/ Sanford L. Severin, M.D.

                                   Printed Name: Sanford L. Severin, M.D.

                                   Title:
                                   (if  signing  in  a representative capacity)



HORIZON:                           Horizon Vision Centers, Inc.

                                   Signature: /s/ David Bates

                                   Printed Name: David Bates

                                   Title: President



PRIME:                             Prime/BDR Acquisition, L.L.C.

                                   Signature: /s/ Cheryl Williams

                                   Printed Name: Cheryl Williams

                                   Title: Vice President
<PAGE>


                             EXCLUSIVE USE AGREEMENT

         This Exclusive Use Agreement  (this  "Agreement") is entered into as of
the 1st day of  September,  1999  (the  "Effective  Date"),  by the  undersigned
shareholder  (the  "Equity  Holder") of Horizon  Vision  Center,  Inc., a Nevada
corporation  ("Horizon")  for the benefit of Horizon and Prime/BDR  Acquisition,
L.L.C., a Delaware limited  liability company ("Prime") and the parent companies
and affiliates of each of Horizon and Prime.

                                    RECITALS:

         WHEREAS, the Equity Holder is a shareholder of Horizon.

         WHEREAS,  the Equity  Holder is a physician or other  licensed  medical
professional.

         WHEREAS,   concurrently   with  the  execution  and  delivery  of  this
Agreement,  Prime and Horizon  are  consummating  that  certain  Stock  Purchase
Agreement (the "Stock Purchase Agreement"), dated September 1, 1999.

         WHEREAS,  in order to  induce  Horizon  and  Prime  to  consummate  the
transactions contemplated by the Stock Purchase Agreement, the Equity Holder has
agreed,  for a period of five (5)  years,  to  perform  all  Refractive  Surgery
Services (as defined  herein)  exclusively  at the  facilities of, and using the
equipment of, Horizon.

         THEREFORE, the parties hereto agree as follows:

                                   AGREEMENTS:

         1. Exclusive Use. Except as expressly  otherwise provided below, during
the term of this  Agreement,  the Equity Holder hereby agrees that,  without the
prior written consent of both Horizon and Prime, the Equity Holder will perform,
and will direct all other medically  trained or licensed  medical  professionals
under the  direction  or control of Equity  Holder to  perform,  all  Refractive
Surgery Services only at the facilities of, and using the equipment of, Horizon.
For purposes of this Agreement,  "Refractive Surgery Services" shall include all
refractive  surgery  modalities,  now or at any  time  during  the  term of this
Agreement performed,  offered or made available,  including, without limitation,
implantable   contact   lenses,   instromal   corneal  rings,   laser  in  situs
keratomileusis   photorefractive  keratectomy,   radial  keratotomy,   automated
lemellar   keratoplasty,   astigmatic  keratotomy  and  similar  or  replacement
procedures.

         Provided, however, that nothing in this Agreement shall be construed to
require Equity Holder to perform  Refractive  Surgery Services at the facilities
of, or use the equipment of, Horizon, if in Equity Holder's professional medical
judgment,  such use would be detrimental to Equity Holder's  patients.  Provided
further,  that this Agreement shall not apply to any Refractive Surgery Services
to be paid for, or reimbursed  by,  Medicare,  Medicaid,  Champus,  or any other
state or  federal  health  care  program,  or in any  other  instance  where the
operation of this Agreement would constitute a violation of applicable law.

         2.  Access.  Horizon  and Prime each agree that during the term of this
Agreement,  and for as long Equity  Holder  continues to meet the  credentialing
requirements of Horizon's  credentialing program as in effect from time to time,
Equity Holder shall be given access to Horizon's facilities, equipment and staff
in the same manner  such access has  generally  been  provided to Equity  Holder
prior to the date of this Agreement.

         3. Other Agreements.  Horizon and Prime each agree that during the term
of this  Agreement  and  for as long as  Equity  Holder  continues  to meet  the
credentialing  requirements of Horizon's credentialing program as in effect from
time to time,  Equity  Holder's  compensation  arrangement  will be  modified to
incorporate the terms of any  compensation  arrangement with any other physician
utilizing the  facilities,  equipment and staff,  to the extent such other terms
are substantially more favorable than the terms enjoyed by Equity Holder.

         4.  Allocation  of  Procedures.  Horizon  and  Prime  each  agree  that
inquiries  generated  by  Horizon  and not by a  particular  physician  shall be
distributed  among the  physician  shareholders  of  Horizon  (including  Equity
Holder) in a manner  consistent with the allocation  methods employed by Horizon
prior to the date of this  Agreement,  limited,  however,  in instances  where a
physician is not available to perform the procedure.

     5. Term. The term of this  Agreement  shall begin on the Effective Date and
shall continue for a period of five (5) years thereafter.

         6. Breach.  The Equity  Holder  agrees that a violation of any covenant
contained  in  Section 1 will  irreparably  damage  Horizon  and Prime for which
remedies at law may be  insufficient,  and for that  reason,  the Equity  Holder
further  agrees  that  Horizon  and Prime  shall each be entitled as a matter of
right to equitable  remedies,  including  specific  performance  and  injunctive
relief,  therefor. The right to specific performance and injunctive relief shall
be cumulative and in addition to whatever other  remedies,  at law or in equity,
that Horizon and Prime may have, including, specifically, recovery of additional
damages.

         7.       Miscellaneous.

               (a) Amendments. This Agreement may be modified or amended only by
          an instrument in writing executed by each of the parties hereto.

               (b) Headings.  The headings  contained in this  Agreement are for
          reference purposes only and shall not affect in any way the meaning or
          interpretation of this Agreement.

                  (c) Counterparts. This Agreement may be executed in any number
         of  counterparts,  each of which  shall be deemed an  original,  but in
         making proof hereof it shall not be necessary to produce or account for
         more than one such counterpart.

               (d) Governing Law. This Agreement shall be construed and enforced
          in accordance  with the internal  laws of the State of Texas,  and not
          the conflicts of law provisions thereof.

               (e) Parties Bound.  This  Agreement  shall be binding upon and be
          enforceable  against the Equity Holder.  This Agreement shall inure to
          the  benefit  of  Horizon,  Prime  and  their  respective  successors,
          representatives and assigns.

               (f) Assignment.  This Agreement and the rights granted  hereunder
          may not be assigned by Equity  Holder  without the written  consent of
          both Horizon and Prime.

                  (g)  Construction.  This Agreement shall be construed  without
         regard to the identity of the person who drafted the various provisions
         of this Agreement.  Each and every provision of this Agreement shall be
         construed  as though  all of the  parties  participated  equally in the
         drafting of this Agreement.  Consequently,  the parties acknowledge and
         agree that any rule of construction  that a document is to be construed
         against the drafting party shall not be applicable to this Agreement.

                  (h)  Severability.  This Agreement is intended to be performed
         in accordance with, and only to the extent permitted by, all applicable
         laws,  ordinances,  rules and  regulations.  If any  provision  of this
         Agreement,  or the application  thereof to any person or  circumstance,
         shall,  for any reason and to any extent,  be invalid or  unenforceable
         but the extent of the invalidity or  unenforceability  does not destroy
         the basis of the bargain between the parties as contained  herein,  the
         remainder of this  Agreement and the  application  of such provision to
         other  persons or  circumstances  shall not be  effected  thereby,  but
         rather shall be enforced to the fullest extent permitted by law.

                                                    [Signature page to follow]
                                                     -------------------------


<PAGE>
                                SIGNATURE PAGE TO

                             EXCLUSIVE USE AGREEMENT

         EXECUTED to be effective as of the date first above written.

EQUITY HOLDER:

                                   Signature: /s/ Stephen G. Turner, M.D.

                                   Printed Name: Stephen G. Turner, M.D.

                                   Title:
                                   (if  signing  in  a representative capacity)



HORIZON:                           Horizon Vision Centers, Inc.

                                   Signature: /s/ David Bates

                                   Printed Name: David Bates

                                   Title: President



PRIME:                             Prime/BDR Acquisition, L.L.C.

                                   Signature: /s/ Cheryl Williams

                                   Printed Name: Cheryl Williams

                                   Title: Vice President


<PAGE>


                             EXCLUSIVE USE AGREEMENT

         This Exclusive Use Agreement  (this  "Agreement") is entered into as of
the 1st day of  September,  1999  (the  "Effective  Date"),  by the  undersigned
shareholder  (the  "Equity  Holder") of Horizon  Vision  Center,  Inc., a Nevada
corporation  ("Horizon")  for the benefit of Horizon and Prime/BDR  Acquisition,
L.L.C., a Delaware limited  liability company ("Prime") and the parent companies
and affiliates of each of Horizon and Prime.

                                    RECITALS:

         WHEREAS, the Equity Holder is a shareholder of Horizon.

         WHEREAS,  the Equity  Holder is a physician or other  licensed  medical
professional.

         WHEREAS,   concurrently   with  the  execution  and  delivery  of  this
Agreement,  Prime and Horizon  are  consummating  that  certain  Stock  Purchase
Agreement (the "Stock Purchase Agreement"), dated September 1, 1999.

         WHEREAS,  in order to  induce  Horizon  and  Prime  to  consummate  the
transactions contemplated by the Stock Purchase Agreement, the Equity Holder has
agreed,  for a period of five (5)  years,  to  perform  all  Refractive  Surgery
Services (as defined  herein)  exclusively  at the  facilities of, and using the
equipment of, Horizon.

         THEREFORE, the parties hereto agree as follows:

                                   AGREEMENTS:

         1. Exclusive Use. Except as expressly  otherwise provided below, during
the term of this  Agreement,  the Equity Holder hereby agrees that,  without the
prior written consent of both Horizon and Prime, the Equity Holder will perform,
and will direct all other medically  trained or licensed  medical  professionals
under the  direction  or control of Equity  Holder to  perform,  all  Refractive
Surgery Services only at the facilities of, and using the equipment of, Horizon.
For purposes of this Agreement,  "Refractive Surgery Services" shall include all
refractive  surgery  modalities,  now or at any  time  during  the  term of this
Agreement performed,  offered or made available,  including, without limitation,
implantable   contact   lenses,   instromal   corneal  rings,   laser  in  situs
keratomileusis   photorefractive  keratectomy,   radial  keratotomy,   automated
lemellar   keratoplasty,   astigmatic  keratotomy  and  similar  or  replacement
procedures.

         Provided, however, that nothing in this Agreement shall be construed to
require Equity Holder to perform  Refractive  Surgery Services at the facilities
of, or use the equipment of, Horizon, if in Equity Holder's professional medical
judgment,  such use would be detrimental to Equity Holder's  patients.  Provided
further,  that this Agreement shall not apply to any Refractive Surgery Services
to be paid for, or reimbursed  by,  Medicare,  Medicaid,  Champus,  or any other
state or  federal  health  care  program,  or in any  other  instance  where the
operation of this Agreement would constitute a violation of applicable law.

         2.  Access.  Horizon  and Prime each agree that during the term of this
Agreement,  and for as long Equity  Holder  continues to meet the  credentialing
requirements of Horizon's  credentialing program as in effect from time to time,
Equity Holder shall be given access to Horizon's facilities, equipment and staff
in the same manner  such access has  generally  been  provided to Equity  Holder
prior to the date of this Agreement.

         3. Other Agreements.  Horizon and Prime each agree that during the term
of this  Agreement  and  for as long as  Equity  Holder  continues  to meet  the
credentialing  requirements of Horizon's credentialing program as in effect from
time to time,  Equity  Holder's  compensation  arrangement  will be  modified to
incorporate the terms of any  compensation  arrangement with any other physician
utilizing the  facilities,  equipment and staff,  to the extent such other terms
are substantially more favorable than the terms enjoyed by Equity Holder.

         4.  Allocation  of  Procedures.  Horizon  and  Prime  each  agree  that
inquiries  generated  by  Horizon  and not by a  particular  physician  shall be
distributed  among the  physician  shareholders  of  Horizon  (including  Equity
Holder) in a manner  consistent with the allocation  methods employed by Horizon
prior to the date of this  Agreement,  limited,  however,  in instances  where a
physician is not available to perform the procedure.

     5. Term. The term of this  Agreement  shall begin on the Effective Date and
shall continue for a period of five (5) years thereafter.

         6. Breach.  The Equity  Holder  agrees that a violation of any covenant
contained  in  Section 1 will  irreparably  damage  Horizon  and Prime for which
remedies at law may be  insufficient,  and for that  reason,  the Equity  Holder
further  agrees  that  Horizon  and Prime  shall each be entitled as a matter of
right to equitable  remedies,  including  specific  performance  and  injunctive
relief,  therefor. The right to specific performance and injunctive relief shall
be cumulative and in addition to whatever other  remedies,  at law or in equity,
that Horizon and Prime may have, including, specifically, recovery of additional
damages.

         7.       Miscellaneous.

               (a) Amendments. This Agreement may be modified or amended only by
          an instrument in writing executed by each of the parties hereto.

               (b) Headings.  The headings  contained in this  Agreement are for
          reference purposes only and shall not affect in any way the meaning or
          interpretation of this Agreement.

                  (c) Counterparts. This Agreement may be executed in any number
         of  counterparts,  each of which  shall be deemed an  original,  but in
         making proof hereof it shall not be necessary to produce or account for
         more than one such counterpart.

               (d) Governing Law. This Agreement shall be construed and enforced
          in accordance  with the internal  laws of the State of Texas,  and not
          the conflicts of law provisions thereof.

               (e) Parties Bound.  This  Agreement  shall be binding upon and be
          enforceable  against the Equity Holder.  This Agreement shall inure to
          the  benefit  of  Horizon,  Prime  and  their  respective  successors,
          representatives and assigns.

               (f) Assignment.  This Agreement and the rights granted  hereunder
          may not be assigned by Equity  Holder  without the written  consent of
          both Horizon and Prime.

                  (g)  Construction.  This Agreement shall be construed  without
         regard to the identity of the person who drafted the various provisions
         of this Agreement.  Each and every provision of this Agreement shall be
         construed  as though  all of the  parties  participated  equally in the
         drafting of this Agreement.  Consequently,  the parties acknowledge and
         agree that any rule of construction  that a document is to be construed
         against the drafting party shall not be applicable to this Agreement.

                  (h)  Severability.  This Agreement is intended to be performed
         in accordance with, and only to the extent permitted by, all applicable
         laws,  ordinances,  rules and  regulations.  If any  provision  of this
         Agreement,  or the application  thereof to any person or  circumstance,
         shall,  for any reason and to any extent,  be invalid or  unenforceable
         but the extent of the invalidity or  unenforceability  does not destroy
         the basis of the bargain between the parties as contained  herein,  the
         remainder of this  Agreement and the  application  of such provision to
         other  persons or  circumstances  shall not be  effected  thereby,  but
         rather shall be enforced to the fullest extent permitted by law.

                                                    [Signature page to follow]
                                                     -------------------------


<PAGE>


S-1



                                SIGNATURE PAGE TO

                             EXCLUSIVE USE AGREEMENT

         EXECUTED to be effective as of the date first above written.

EQUITY HOLDER:
                                   Signature: /s/ Stephen Wilmarth, M.D.

                                   Printed Name: Stephen Wilmarth

                                   Title:
                                   (if  signing  in  a representative capacity)



HORIZON:                           Horizon Vision Centers, Inc.

                                   Signature: /s/ David P. Bates

                                   Printed Name: David P. Bates

                                   Title: President



PRIME:                             Prime/BDR Acquisition, L.L.C.

                                   Signature: /s/ Cheryl Williams

                                   Printed Name: Cheryl Williams

                                   Title: Vice President


<PAGE>


                             EXCLUSIVE USE AGREEMENT

         This Exclusive Use Agreement  (this  "Agreement") is entered into as of
the 1st day of  September,  1999  (the  "Effective  Date"),  by the  undersigned
shareholder  (the  "Equity  Holder") of Horizon  Vision  Center,  Inc., a Nevada
corporation  ("Horizon")  for the benefit of Horizon and Prime/BDR  Acquisition,
L.L.C., a Delaware limited  liability company ("Prime") and the parent companies
and affiliates of each of Horizon and Prime.

                                    RECITALS:

         WHEREAS, the Equity Holder is a shareholder of Horizon.

         WHEREAS,  the Equity  Holder is a physician or other  licensed  medical
professional.

         WHEREAS,   concurrently   with  the  execution  and  delivery  of  this
Agreement,  Prime and Horizon  are  consummating  that  certain  Stock  Purchase
Agreement (the "Stock Purchase Agreement"), dated September 1, 1999.

         WHEREAS,  in order to  induce  Horizon  and  Prime  to  consummate  the
transactions contemplated by the Stock Purchase Agreement, the Equity Holder has
agreed,  for a period of five (5)  years,  to  perform  all  Refractive  Surgery
Services (as defined  herein)  exclusively  at the  facilities of, and using the
equipment of, Horizon.

         THEREFORE, the parties hereto agree as follows:

                                   AGREEMENTS:

         1. Exclusive Use. Except as expressly  otherwise provided below, during
the term of this  Agreement,  the Equity Holder hereby agrees that,  without the
prior written consent of both Horizon and Prime, the Equity Holder will perform,
and will direct all other medically  trained or licensed  medical  professionals
under the  direction  or control of Equity  Holder to  perform,  all  Refractive
Surgery Services only at the facilities of, and using the equipment of, Horizon.
For purposes of this Agreement,  "Refractive Surgery Services" shall include all
refractive  surgery  modalities,  now or at any  time  during  the  term of this
Agreement performed,  offered or made available,  including, without limitation,
implantable   contact   lenses,   instromal   corneal  rings,   laser  in  situs
keratomileusis   photorefractive  keratectomy,   radial  keratotomy,   automated
lemellar   keratoplasty,   astigmatic  keratotomy  and  similar  or  replacement
procedures.

         Provided, however, that nothing in this Agreement shall be construed to
require Equity Holder to perform  Refractive  Surgery Services at the facilities
of, or use the equipment of, Horizon, if in Equity Holder's professional medical
judgment,  such use would be detrimental to Equity Holder's  patients.  Provided
further,  that this Agreement shall not apply to any Refractive Surgery Services
to be paid for, or reimbursed  by,  Medicare,  Medicaid,  Champus,  or any other
state or  federal  health  care  program,  or in any  other  instance  where the
operation of this Agreement would constitute a violation of applicable law.

         2.  Access.  Horizon  and Prime each agree that during the term of this
Agreement,  and for as long Equity  Holder  continues to meet the  credentialing
requirements of Horizon's  credentialing program as in effect from time to time,
Equity Holder shall be given access to Horizon's facilities, equipment and staff
in the same manner  such access has  generally  been  provided to Equity  Holder
prior to the date of this Agreement.

         3. Other Agreements.  Horizon and Prime each agree that during the term
of this  Agreement  and  for as long as  Equity  Holder  continues  to meet  the
credentialing  requirements of Horizon's credentialing program as in effect from
time to time,  Equity  Holder's  compensation  arrangement  will be  modified to
incorporate the terms of any  compensation  arrangement with any other physician
utilizing the  facilities,  equipment and staff,  to the extent such other terms
are substantially more favorable than the terms enjoyed by Equity Holder.

         4.  Allocation  of  Procedures.  Horizon  and  Prime  each  agree  that
inquiries  generated  by  Horizon  and not by a  particular  physician  shall be
distributed  among the  physician  shareholders  of  Horizon  (including  Equity
Holder) in a manner  consistent with the allocation  methods employed by Horizon
prior to the date of this  Agreement,  limited,  however,  in instances  where a
physician is not available to perform the procedure.

     5. Term. The term of this  Agreement  shall begin on the Effective Date and
shall continue for a period of five (5) years thereafter.

         6. Breach.  The Equity  Holder  agrees that a violation of any covenant
contained  in  Section 1 will  irreparably  damage  Horizon  and Prime for which
remedies at law may be  insufficient,  and for that  reason,  the Equity  Holder
further  agrees  that  Horizon  and Prime  shall each be entitled as a matter of
right to equitable  remedies,  including  specific  performance  and  injunctive
relief,  therefor. The right to specific performance and injunctive relief shall
be cumulative and in addition to whatever other  remedies,  at law or in equity,
that Horizon and Prime may have, including, specifically, recovery of additional
damages.

         7.       Miscellaneous.

               (a) Amendments. This Agreement may be modified or amended only by
          an instrument in writing executed by each of the parties hereto.

               (b) Headings.  The headings  contained in this  Agreement are for
          reference purposes only and shall not affect in any way the meaning or
          interpretation of this Agreement.

                  (c) Counterparts. This Agreement may be executed in any number
         of  counterparts,  each of which  shall be deemed an  original,  but in
         making proof hereof it shall not be necessary to produce or account for
         more than one such counterpart.

               (d) Governing Law. This Agreement shall be construed and enforced
          in accordance  with the internal  laws of the State of Texas,  and not
          the conflicts of law provisions thereof.

               (e) Parties Bound.  This  Agreement  shall be binding upon and be
          enforceable  against the Equity Holder.  This Agreement shall inure to
          the  benefit  of  Horizon,  Prime  and  their  respective  successors,
          representatives and assigns.

               (f) Assignment.  This Agreement and the rights granted  hereunder
          may not be assigned by Equity  Holder  without the written  consent of
          both Horizon and Prime.

                  (g)  Construction.  This Agreement shall be construed  without
         regard to the identity of the person who drafted the various provisions
         of this Agreement.  Each and every provision of this Agreement shall be
         construed  as though  all of the  parties  participated  equally in the
         drafting of this Agreement.  Consequently,  the parties acknowledge and
         agree that any rule of construction  that a document is to be construed
         against the drafting party shall not be applicable to this Agreement.

                  (h)  Severability.  This Agreement is intended to be performed
         in accordance with, and only to the extent permitted by, all applicable
         laws,  ordinances,  rules and  regulations.  If any  provision  of this
         Agreement,  or the application  thereof to any person or  circumstance,
         shall,  for any reason and to any extent,  be invalid or  unenforceable
         but the extent of the invalidity or  unenforceability  does not destroy
         the basis of the bargain between the parties as contained  herein,  the
         remainder of this  Agreement and the  application  of such provision to
         other  persons or  circumstances  shall not be  effected  thereby,  but
         rather shall be enforced to the fullest extent permitted by law.

                                                    [Signature page to follow]
                                                     -------------------------


<PAGE>


S-1



                                SIGNATURE PAGE TO

                             EXCLUSIVE USE AGREEMENT

         EXECUTED to be effective as of the date first above written.

EQUITY HOLDER:
                                   Signature: /s/ Robert J. Hardy

                                   Printed Name: Robert J. Hardy

                                   Title:
                                   (if  signing  in  a representative capacity)



PRIME:                             Prime/BDR Acquisition, L.L.C.

                                   Signature: /s/ Cheryl Williams

                                   Printed Name: Cheryl Williams

                                   Title: Vice President