REFRACTIVE LASER CENTER

                              MANAGEMENT AGREEMENT

         THIS  REFRACTIVE  LASER  CENTER   MANAGEMENT   AGREEMENT   ("Management
Agreement") is made and entered into as of March 1, 2000 (the "Effective Date"),
by and between Prime MBC,  L.L.C.,  a Delaware  limited  liability  company (the
"Center  Company")  and Mann  Berkeley Eye Center,  P.A.,  a Texas  professional
association  ("MBEC").  The Center Company and MBEC are collectively referred to
herein as the "Parties".

                                    Recitals

         WHEREAS, Prime RVC, Inc., a Delaware corporation ("Prime"), acquired an
ownership  interest in Center Company (the "Purchase")  pursuant to that certain
Contribution Agreement dated as of March 1, 2000 (the "Contribution  Agreement")
by and among Prime,  the Center Company,  MBEC, MBC Holding  Company,  L.L.C., a
Texas limited  liability  company  ("Target  Center"),  Paul Michael Mann, M.D.,
Ralph G. Berkeley, M.D., Michael B. Caplan, M.D. and Mark F. Micheletti; and

         WHEREAS, pursuant to the Contribution Agreement the Center Company owns
and operates a refractive laser center in Austin, Texas (the "Center") which was
previously owned by Target Center and managed by MBEC; and

         WHEREAS,  in connection  with, and pursuant to, the Purchase,  MBEC has
agreed to continue to provide management and marketing services to, and bear the
same type of expenses  and employ all  employees on behalf of,  Center  Company,
consistent  with MBEC's past practices in connection with Target Center (subject
to  appropriate  adjustment  for any  growth of Center  Company or  increase  in
patient volume at the Center during the term of this Management Agreement);

         WHEREAS,  the  Center  Company  desires to engage  and  delegate  daily
administrative and operational  responsibility for the Center to MBEC,  pursuant
to specified terms, conditions, and controls; and

         WHEREAS,  MBEC desires to provide such management  services pursuant to
the terms and conditions set forth herein;

         NOW, THEREFORE, the Parties hereby mutually agree as follows:

                                    AGREEMENT

1. Appointment.  The Center Company hereby appoints MBEC as contract manager for
the Center  ("Appointment")  and MBEC hereby accepts such Appointment,  upon the
provisions and conditions set forth in this  Management  Agreement.  MBEC hereby
agrees and  acknowledges  that its execution and  performance of this Management
Agreement is a material  inducement to the execution and performance by Prime of
the Contribution Agreement.  Accordingly,  Prime is a third party beneficiary of
this Agreement.

2.  Term and  Renewal.  The  initial  term of this  Management  Agreement  shall
commence upon the Effective Date and shall  continue  thereafter for a period of
five (5) years (the "Initial  Term").  Thereafter,  the term of this  Management
Agreement shall  automatically  renew for successive five (5) year terms, unless
terminated by either party by giving  written notice of termination at least 180
days  prior  to the end of the  Initial  Term or any  renewal  term,  or  unless
terminated  for  cause as set  forth in  Section  3.  The  Initial  Term and all
renewals thereof shall be referred to herein as the "Term."

3.   Termination.  During the Term, this Management  Agreement may be terminated
     only  upon  the  occurrence  of any of the  following  events  ("Events  of
     Termination"), which shall be deemed a termination for cause:

(a)      By MBEC  upon the  failure  by  Center  Company  to make  payments  due
         hereunder  (other than a payment  being  disputed by Center  Company in
         good faith),  or the failure by Center Company to allow MBEC to collect
         a Management Fee (as hereinafter  defined) pursuant to a Fee Report (as
         hereinafter defined) approved,  or deemed approved,  by Center Company,
         which  failure  remains  uncured  for a period of ten (10)  days  after
         written notice,  or by a non-breaching  Party in the event of a failure
         by any other Party to perform a material  obligation  hereunder,  which
         failure  remains  uncured  for a period of thirty  (30) days  following
         written notice thereof by the non-breaching Party;

(b)      By the Center Company upon a final judicial  determination  having been
         made, not subject to further appeal, that MBEC was grossly negligent in
         performance of its obligations  hereunder or committed a fraud upon the
         Center Company;

(c)      By the Center  Company in the event any  officer or director of MBEC or
         any affiliate  thereof is convicted on a charge  constituting  a felony
         involving moral turpitude under the laws of the State of Texas;

(d)      By the  Center  Company  in the event of the  involuntary  transfer  or
         assignment  of a majority of the voting  securities of MBEC to a person
         or entity other than an affiliate of MBEC;

(e)      By the Center  Company in the event  MBEC makes an  assignment  for the
         benefit of  creditors,  files a voluntary  petition in  bankruptcy,  is
         adjudicated a bankrupt or insolvent, or has ordered against it an order
         for any relief in any bankruptcy or insolvency proceeding;

(f)      By the Center  Company  in the event  MBEC  files a petition  or answer
         seeking any  reorganization,  arrangement,  composition,  readjustment,
         liquidation,  dissolution, or similar relief under any statute, law, or
         regulation or fails to contest the material  allegations  of a petition
         filed against it in a proceeding of such nature;

(g)  By the Center  Company in the event MBEC seeks,  consents to, or acquiesces
     in the appointment of a trustee,  receiver, or liquidator of MBEC or all or
     any substantial part of its properties;

(h)      By the  Center  Company  in the event of any  proceeding  against  MBEC
         seeking   reorganization,   arrangement,   composition,   readjustment,
         liquidation,  dissolution, or similar relief under any statute, law, or
         regulation  not having been  dismissed  within one hundred twenty (120)
         days after the commencement thereof;

(i)      By the  Center  Company in the event of the  appointment  of a trustee,
         receiver,  or liquidator for MBEC or all or any substantial part of its
         properties  without  the  consent  or  acquiescence  of MBEC,  and such
         appointment  not  being  vacated  or stayed  within  90 days  after the
         appointment,  or, if stayed,  the  appointment  not having been vacated
         within 90 days after the expiration of any such stay; or

(j)      By a  non-breaching  Party in the  event  of a  default  of a  material
         obligation  by any other  Party  under  any  Transaction  Document  (as
         defined in the Contribution  Agreement),  which default remains uncured
         for a period of thirty (30) days after written  notice of such default,
         provided it is possible to cure such default  within  thirty (30) days.
         Solely for the  purposes of a  termination  for cause  pursuant to this
         Section,  "material"  shall mean an economic impact  exceeding  $5,000,
         disregarding  any  amount  calculated  as  related  legal fees or legal
         costs.

4. Center Governance and Control. The overall control,  policy development,  and
quality  assurance  of and for the  Center is vested in the Center  Company.  In
performance of its duties hereunder,  MBEC shall provide monthly written reports
to Center Company's Board of Managers (the "Board") on the Center's development,
operations,  and financial performance ("Monthly Reports") and, as needed, shall
supplement such reports with additional data and/or meetings with Board members.

5. Duties of MBEC.  All  compensation  for  services  provided by MBEC to Center
Company pursuant to this Management Agreement is included in the Management Fee,
and MBEC  shall  have no right to any other  payment,  reimbursement  or offset,
other than the Management Fee, for services  provided or costs incurred pursuant
to this  Management  Agreement.  Accordingly,  MBEC  shall have no right to bind
Center Company or incur any obligations or expenses on Center Company's  behalf.
MBEC shall bear all costs and expenses  incurred in the business,  operation and
management  of Center  Company and the Center,  with the exception of the office
lease for the Center,  certain  equipment  maintenance (as paid by Target Center
immediately prior to the Purchase),  and real estate and franchise taxes,  which
costs shall be borne by Center Company. MBEC acknowledges and agrees that Center
Company has no employees,  and that all employees  providing services for Center
Company  shall be  employed  by, and all  employee  salaries  and  benefits  (if
applicable) shall be the obligation of, MBEC.

         MBEC shall,  subject to the  oversight  of the Board,  have the general
responsibility  and  authority  to  implement  all  facets  of total  management
services to and for the Center,  in accordance with Board  policies,  including,
but not limited to, the following:

(a)  Strategic Planning. MBEC shall assist the Board in identifying,  assessing,
     and reviewing annual and long-range  strategies,  goals, and objectives for
     the Center and shall implement approved plans.

(b)      Budgets,  Forecasts,  and  Approved  Expenditures.  MBEC shall  develop
         annual forecasts and recommended  annual capital and operating  budgets
         for the Center,  inclusive of items of revenues and expense customarily
         associated with operations of this type ("Budgets"),  and shall present
         these to the Board for review and approval. Thereafter, MBEC shall have
         responsibility for implementing  approved Budgets and for measuring and
         assessing the Center's performance against same in the Monthly Reports.

(c)      Policies  and  Procedures.  MBEC shall  assist the Board in  developing
         policies and procedures  consistent with the Center's quality assurance
         standards  and  with  requirements,  if any,  of  licensing  and  other
         regulatory groups,  third party payors, and accreditation  bodies which
         may have authority or influence on delivery of refractive laser patient
         care.   MBEC  shall  have   responsibility   for   implementation   and
         administration  of policies and  procedures  approved by the Board,  in
         accordance with all applicable regulation.

(d)      Licenses and Permits.  MBEC shall apply for,  renew,  and exercise best
         efforts to obtain and  maintain any and all  licenses,  certifications,
         and permits as are required for the operation of the Center and payment
         for services provided therein.

(e)      Accreditation.  MBEC shall  exercise  best  efforts to assure  that the
         Center's  policies,  procedures,  and practices  meet  standards of any
         groups  from  which  the  Center  may seek  accreditation.  MBEC  shall
         coordinate  timely  preparation of  applications  for and completion of
         surveys related to any such accreditation.

(f)      Insurance and Risk Management. MBEC shall evaluate and obtain insurance
         policies pertinent to property,  casualty,  professional liability, and
         such other risks as are encountered in operations of the Center's type.
         MBEC shall pay for accepted  policies when due,  maintain such policies
         in full  force and  effect,  and shall  coordinate  steps to assure any
         claims are processed and/or defended appropriately.

(g)      Participation Agreements and Third Party Contracting. MBEC shall assure
         all required forms,  applications,  and fees are conveyed timely by the
         Center to continue its  participation  in any  appropriate  third party
         payment  programs  approved  by the  Board.  Additionally,  MBEC  shall
         identify and negotiate  appropriate managed care contracts on behalf of
         the Center consistent with approved policies.

(h)      Professional  Staff. MBEC shall coordinate the process of assuring that
         application and credentialing processes are completed for appropriately
         licensed clinical professionals seeking staff membership at the Center.
         MBEC  further  shall  coordinate  documentation  of  such  individuals'
         training  and  continuing   education   related  to  refractive   laser
         procedures.

(i)  Employee  Matters.  MBEC shall provide its  employees to Center  Company in
     accordance  with  Board   instructions,   current  operational  needs,  and
     applicable regulations.

(j)      Billing and Collections. MBEC shall identify systems and procedures for
         the timely  billing and collection of patient  charges and/or  facility
         fees, as applicable,  associated with the Center's services. MBEC shall
         cause Board-approved billing and collections systems to be implemented.

(k)  Banking and Financial  Records.  MBEC shall assure segregated bank accounts
     are maintained with a financial  institution selected by Center Company and
     Prime,  whose  authorized  signatory shall be determined by the Board,  for
     deposit of Center Company funds.  All cash flow and funds of Center Company
     received by, or in the possession of, MBEC, shall be promptly  deposited by
     MBEC in such  accounts.  MBEC shall  maintain books of records and accounts
     for Center  Company  in  conformance  with  generally  accepted  accounting
     principles,  consistently  applied.  MBEC shall  submit  monthly  financial
     statements to the Board by the 10th day of the following  month and will be
     responsible for the timely  preparation of the annual reports by January 31
     of the following year. Neither MBEC nor any of its officers,  directors, or
     employees shall have any signatory authority over any bank account or other
     financial  account of the Center or the Center Company,  except to disburse
     the Management Fee pursuant to an accepted (or deemed accepted) Fee Report.
     MBEC shall have no right of offset with respect to any Center Company funds
     or Center funds.

(l)      Procurement.  MBEC shall negotiate  arrangements for the cost-effective
         purchasing  of  equipment  and  supplies  necessary  to  carry  out the
         Center's operations in conformance with its quality assurance standards
         and those of applicable  regulatory and accreditation  bodies, and MBEC
         shall provide all necessary equipment and supplies.

(m)      Marketing.  Upon  request of the Board,  MBEC  shall  recommend  and/or
         evaluate  feasibility  of  potential  promotional  programs  for Center
         services and implement any such Board-approved  programs. The foregoing
         notwithstanding, MBEC shall continue to provide to Center Company, at a
         minimum,  the same amount and quality of marketing services,  materials
         and programs as MBEC provided to Target Center immediately prior to the
         Purchase;  provided  this  shall  not  require  MBEC  to  increase  its
         marketing efforts to accommodate increases in the general population of
         the Austin metropolitan area that occur after the Effective Date.

(n)      Utilization Review and Outcomes  Assessment.  MBEC shall coordinate the
         formation and  activities  of such clinical  review groups as the Board
         shall  determine are required to help assure  services  provided at the
         Center are medically  appropriate and rendered in a fashion  associated
         with sound clinical practice and outcomes.

6. Standards of Performance.  At all times when performing its duties hereunder,
MBEC shall act in good faith, promptly, with due diligence,  professionally, and
in a manner  which will  ensure  that the Center is  operated  to provide a high
standard of health care on a fiscally  prudent  basis.  Such  performance  shall
conform to accepted business practice within the health care industry  generally
in  Texas  and  to  standards  prescribed  by  entities  accrediting  facilities
providing  treatments  such as those  of the  Center.  MBEC  shall  provide  the
services required under this Agreement in a manner consistent with the levels of
service  and  standards  of quality  provided  to Target  Center by MBEC for all
periods prior to the date of this Agreement  (subject to appropriate  adjustment
for any growth of Center  Company or  increase  in patient  volume at the Center
during the term of this Management Agreement).  MBEC shall refrain from entering
into any  arrangement  on behalf of the Center  with any party  related to MBEC,
unless such arrangement is made with the prior knowledge and written approval of
the Board.

7.       Management Fees.
         ---------------

(a)      Overall Fee. In consideration  for its services  hereunder,  MBEC shall
         receive a fee  ("Management  Fee"),  payable  on a  calendar  quarterly
         basis, equal to five percent (5%) of net collections  annually. As used
         herein,  "net  collections"  shall  mean  all  facility  fees  actually
         collected  by or for Center  Company for  procedures  performed  at the
         Center during the applicable  calendar  quarter,  less all  contractual
         allowances and discounts.

(b)  Fee Reports;  Payment.  On or before each January 15, April 15, July 15 and
     October 15,  during the term of this  Agreement,  MBEC shall deliver to the
     Board a report (including reasonable details and supporting  documentation)
     (the "Fee Report")  calculating  net collections and the Management Fee due
     for the immediately  preceding calendar quarter.  Center Company shall have
     fifteen  (15) days from  receipt of the Fee Report to accept the Fee Report
     or to object in  writing  to any item  contained  in the Fee  Report.  MBEC
     agrees to cooperate  fully and promptly  with  requests  from the Board for
     clarification  or  additional  supporting  documentation  related  to a Fee
     Report or the contents thereof.  MBEC acknowledges and agrees that it shall
     require a majority of Prime's designees to the Board to accept or object in
     writing to a Fee Report for purposes of this  Agreement.  If Center Company
     neither  accepts  the Fee Report  nor  objects in writing to the Fee Report
     within fifteen (15) days of its receipt,  the Fee Report shall be deemed to
     be accepted.  Upon the acceptance (or deemed  acceptance) of the Fee Report
     by the Board, MBEC shall be authorized to transfer to itself the Management
     Fee then due.

8. Audit by Center  Company.  Center  Company  and Prime shall have the right to
audit and inspect all of the records of Target Center and the records of MBEC as
it relates to MBEC's services and Management Fees hereunder and as it relates to
patient volumes and demographics for purposes of determining compliance with the
Contribution  Agreement,  and shall not  extend to any other  general  financial
records of MBEC. MBEC shall cooperate and provide access, and shall cause Target
Center to cooperate  and provide  access,  to its relevant  books and records in
connection  with the  exercise of such  right.  In the event of an exercise of a
Party's audit rights under this Section in  connection  with an objection to the
Fee Report or the Management Fee, MBEC shall cause a report to be prepared by an
independent  certified public accountant selected by Center Company and approved
by Prime, said report to be prepared for and addressed to the Center Company and
Prime,   in  a  form   reasonably   acceptable  to  Center  Company  and  Prime,
substantiating MBEC's calculation of net collections and the Management Fee. The
auditing  party must give at least ten (10) days prior written notice to MBEC of
its intent to exercise  its  auditing  rights.  Unless  otherwise  agreed by the
Parties involved,  such audit shall be conducted during normal business hours at
the offices of the Party being audited.

         Any  overpayments  by Center  Company shall be credited,  together with
interest  accrued  thereon at the rate of eighteen  percent (18%) per annum from
the date paid until the date actually due, toward subsequent payment obligations
of Center Company.

         The  auditing  Party  shall  bear all costs and  expenses  of the audit
unless the audit reveals that any  Management  Fee due hereunder was overpaid by
more than five percent (5%),  in which case the auditing  Party will promptly be
reimbursed for all reasonable out-of-pocket costs and expenses incurred by it in
connection with such audit.

9. Access to Center;  Facility Fees.  Center Company agrees to provide MBEC with
access,  on a  non-exclusive  basis,  to the Center for use in the  examination,
counseling and performance of Refractive Surgery (as defined in the Contribution
Agreement).  MBEC shall be  responsible  for  reserving  such access with Center
Company at least five (5) business days in advance.  Center  Company may, at its
sole  discretion,  provide  access  to the  Center to other  physicians  for the
performance  of  Refractive  Surgery,  subject to the  approval by MBEC,  in its
reasonable discretion, of the credentials of such physicians. MBEC agrees to pay
Center Company a facility fee of $720 per Refractive Surgery  procedure,  and an
exam and testing fee of $50 per  Refractive  Surgery  procedure,  both,  payable
monthly,  during the Term of this  Agreement.  In the event that global  patient
charges for Refractive  Surgery services are increased or reduced  (provided the
global  patient  charges are not reduced below  $1,200),  the facility fee shall
automatically  be adjusted so that the  facility  fee shall remain at 40% of the
global  patient  charge;  provided  that in no event shall the  facility  fee be
reduced below $600, without the written consent of at least 60% of the Board. In
the event that  global  patient  charges for  Refractive  Surgery  services  are
reduced (in accordance  with the immediately  preceding  sentence) below $1,200,
the facility fee shall  automatically be adjusted so that the facility fee shall
be 50% of the global patient charge.  The parties  acknowledge and agree that as
of the Effective Date, the global patient charges charged by MBEC are $1,895 per
Refractive Surgery procedure.

10.  Indemnifications;  Materiality.  Each Party hereby  agrees to indemnify and
hold the other Party harmless  against all claims,  liabilities,  expenses,  and
losses of any kind,  including  reasonable  attorney fees,  asserted against the
other Party arising from performance of its obligations hereunder, except if due
to the  willful  or  negligent  acts of the other  Party made in bad faith or in
express  breach  of any  provision  hereunder.  In  addition  to,  and in no way
limiting,  the foregoing  indemnity  obligations,  MBEC shall indemnify and hold
harmless  Center  Company  and  the  Center  against  all  claims,  liabilities,
expenses,  and losses of any kind,  including reasonable attorney fees, asserted
by or  on  behalf  of  any  employee,  former  employee,  agent  or  independent
contractor of MBEC, or their estate. Notwithstanding the foregoing, this Section
10 shall not be construed to contradict  the  indemnification  provisions of the
Contribution   Agreement.   Notwithstanding   anything   contained  herein,  the
indemnification provisions of this Section 10 shall be ineffectual and shall not
permit or require  indemnification for all, or any, losses, costs,  liabilities,
claims or expenses arising, directly or indirectly,  from any action or omission
permitting or requiring indemnification under the Contribution Agreement; and in
no event may any indemnity be allowed  under this  Agreement for amounts paid or
payable  pursuant  to  the   indemnification   provisions  of  the  Contribution
Agreement.  For purposes of this  Agreement,  whenever  there are  references to
"material"  or  "materially,"  such  terms  shall be deemed to mean an  economic
impact exceeding $5,000 with respect to the fact or matter being described.

11.  Notices. All notices required hereunder shall be deemed given properly when
     made in writing and  delivered  by U.S.  Postal  Service or courier,  or by
     postage  prepaid,  as set  forth  below  or as the  Parties  hereafter  may
     designate in accordance with this Paragraph.

(a)      As to the Center Company:
                           Prime MBC, L.L.C.
                           1301 Capital of Texas Hwy., Suite C-300
                           Austin, Texas 78746
                           Attention: Chairman
(b)      As to MBEC:
                           Mann Berkeley Eye Center, P.A.
                           1200 Binz, Suite 1000
                           Houston, Texas  77004
                           Attention: President
12.  Assignment and Succession. This Management Agreement may not be assigned by
     MBEC to any  affiliate  thereof or to any other  entity  without  the prior
     written consent of the Center Company.

13.  Waiver.  No  express or  implied  consent or waiver by either  Party to any
     breach or  default  of the other  Party  with  respect  to this  Management
     Agreement  shall be deemed a consent or waiver to or of any other breach or
     default hereunder.

14.  Severability.  If  any  provision  of  this  Management  Agreement  or  the
application   thereof  to  any  person  or  circumstance  shall  be  invalid  or
unenforceable to any extent, the remainder of this Management  Agreement and the
application of such  provisions to other persons or  circumstances  shall not be
affected thereby and shall be enforced to the greatest extent permitted by law.

15.  Governing  Laws.  This  Management  Agreement  and the  obligations  of the
     Parties  hereunder  shall  be  interpreted,   construed,  and  enforced  in
     accordance with the laws of the State of Texas.

16.  Arbitration.  Any controversy  between the parties regarding this Agreement
and any claims arising out of this Agreement or its breach shall be submitted to
arbitration by either party. The arbitration proceedings shall be conducted by a
single arbitrator  pursuant to the Commercial  Arbitration Rules of the American
Arbitration Association. The arbitration shall be conducted in Dallas, Texas and
the  arbitrator  shall have the right to award actual  damages and attorney fees
and  costs,  but  shall  not have the  right to  award  punitive,  exemplary  or
consequential damages against either party.

17.  Entire  Agreement and Amendment.  This  Management  Agreement  contains the
     entire  agreement  between the Parties.  No variations,  modifications,  or
     changes  shall be binding  upon either Party unless set forth in a document
     duly executed by the Parties.

                            [Signature page follows]


<PAGE>


S-1

                                 SIGNATURE PAGE

                                       TO

                             REFRACTIVE LASER CENTER

                              MANAGEMENT AGREEMENT

         This  Management  Agreement  accepted by signatures and as of the dates
set forth below.

                                                     PRIME MBC, L.L.C.

                                        By:  __________________________________

                                        Printed Name:  _________________________

                                        Title  _________________________________



                                                MANN BERKELEY EYE CENTER, P. A.

                                        By:  __________________________________

                                        Printed Name:  _________________________

                                        Title  _________________________________