AGREEMENT

 
 AGREEMENT made in duplicate, effective May 7, 1996, by and 
between BALLARD MEDICAL PRODUCTS, a Utah corporation ("Ballard") 
and NEURO NAVIGATIONAL CORPORATION, a Delaware corporation (the 
"Company").

 RECITALS:

  A. Effective July 17, 1995, the parties entered into a 
Stock Purchase and Option Agreement (the "Option Agreement").

  B. Ballard purchased the Option (as defined in the Option 
Agreement) pursuant to the Option Agreement on or about November 
14, 1995.

  C. Ballard is now desirous of selling the Option, and the 
parties desire to enter into certain agreements related thereto.  
It is possible that the transaction may, alternatively, be 
structured as a sale of the Company or its assets.

  D. On or about May 7, 1996, Ballard and the Company entered 
into an engagement letter with Vector Securities International, 
Inc. ("Vector"), pursuant to which Ballard and the Company engaged 
Vector to assist them in the sale of greater than a majority of the 
business, assets or stock of the Company which sale might also 
involve a sale of all or a portion of the Option, and/or the 
consummation of one or more Strategic Alliances (as defined 
therein) involving less than a majority of the Company's business, 
assets or stock (the "Engagement Letter"), a copy of which 
Engagement Letter is attached to this Agreement as Exhibit A and 
made a part hereof by reference.

  E. Simultaneously with the parties execution of the 
Engagement Letter, Ballard and the Company also executed an 
indemnity letter with Vector (the "Indemnity Letter"), a copy of 
which Indemnity Letter is attached to this Agreement as Exhibit B 
and made a part hereof by reference.

 NOW, THEREFORE, in consideration of the mutual covenants and 
conditions contained herein and also the covenants and conditions 
set forth in the Option Agreement, the parties agree as follows:

  1. Definitions.  For all purposes of this Agreement, the 
following terms shall have the meaning indicated below:

  (a) "Engagement Letter" shall mean that certain letter 
agreement dated May 7, 1996, from Vector to the Company and 
Ballard.

  (b) "Indemnity Letter" shall mean that certain letter 
agreement dated May 7, 1996 to Vector from the Company and Ballard.

                               15 of 29
<PAGE>

  (c) "Net Proceeds" shall mean the aggregate 
consideration (as described and defined in the Engagement Letter) 
paid by the Purchaser or its shareholders in the consummated 
Transaction, minus all of the following:

   (i) All payments and reimbursements described in 
paragraph 3 below:

   (ii) $2,000,000 (representing the purchase price 
paid by Ballard for its Preferred Shares in the Company), reduced 
by the cash redemption price for the Preferred Shares paid by the 
Company to Ballard pursuant to Section 2.5 of the Option Agreement; 
and

   (iii) The Asset Purchase Price under Section 3.5 of 
the Option Agreement.

  (d) "Purchaser" shall mean the entity which purchases 
the Option.

  (e) "Transaction" shall mean (i) Ballard's sale and 
Purchaser's purchase of the Option as well as Purchaser's exercise 
of the Option and purchase of the Assets, (ii) Ballard's exercise 
of the Option, purchase of the Assets and sale of the Assets to 
Purchaser, or (iii) the consummation of any other transaction 
contemplated in the Engagement Letter, but in the event of a sale 
of the Option, only upon exercise of the Option and purchase of the 
Assets.

  (f) "Vector" shall mean Vector Securities International, 
Inc.

 All other proper nouns used herein shall have the meanings set 
forth in the Option Agreement.

  2. Payment of Indebtedness to Ballard.  Notwithstanding 
provisions to the contrary contained in promissory notes between 
the Company and Ballard, all outstanding promissory notes, loans, 
and indebtedness owed by the Company to Ballard will be due and 
payable in full by the Company immediately upon the consummation of 
any Transaction and receipt by the Company of the proceeds to which 
it is entitled under the Transaction.

  3. Payment of Expenses.  Upon the consummation of a 
Transaction:

  (a) Ballard will be promptly reimbursed out of the 
proceeds of such transaction for all fees and expenses heretofore 
or hereafter paid or incurred to Herbert J. Epstein (or his 
company, Epstein & Associates) in connection with Ballard's 
entering into and performing the Option Agreement and in connection 
with the transaction contemplated by the Engagement Letter 
(although Ballard believes that no fee or commission will be owed 
to Mr. Epstein or his company upon the consummation of the 
transaction contemplated in the Engagement Letter); 

                               16 of 29
<PAGE>

  (b) Ballard will be promptly reimbursed out of said 
proceeds for all fees and expenses heretofore or hereafter paid or 
incurred to Vector in connection with the Engagement Letter; and

  (c) Ballard will be reimbursed out of said proceeds for 
all of its other expenses paid or incurred in connection with the 
Engagement Letter and the transaction contemplated therein.

  4. Allocation of Net Proceeds.  Ballard wishes to keep the 
Company's management team (the "Management Team") listed on Exhibit 
C attached to and made a part of this Agreement by this reference, 
intact and to encourage the Management Team to remain with the 
Company until consummation of the Transaction, and if the terms and 
conditions of the Transaction so provide, for a limited period 
thereafter, in order to facilitate an orderly Transaction at the 
highest possible purchase price.  Consequently, Ballard agrees with 
the Company for the benefit of the Management Team still with the 
Company upon consummation of the Transaction that the Net Proceeds 
for the consummated Transaction shall be allocated as follows:

  (a) The first $1 million of Net Proceeds will be 
allocated and paid to Ballard;

  (b) Of the next $4 million of Net Proceeds, 50% will be 
allocated and paid to Ballard and 50% will be allocated and paid to 
the Management Team;

  (c) Of the next $5 million of Net Proceeds, 60% will be 
allocated and paid to Ballard and 40% will be allocated and paid to 
the Management Team;

  (d) All other Net Proceeds will be allocated and paid to 
Ballard; and

  (e) Any and all sums payable to the Management Team 
pursuant to the foregoing paragraphs shall be immediately paid and 
distributed directly by Ballard, or at the request of Ballard, by 
Purchaser in accordance with the allocations set forth in Exhibit 
C.  Any and all such payments shall be made contemporaneously with 
and as a part of the closing of the Transaction.

  5. Right of Contribution. 

  (a) The parties are jointly and severally liable to 
Vector for various matters under the Engagement Letter and under 
the Indemnity Letter.  The parties desire to allocate 
responsibility for such joint and several liability and indemnity 
obligations.  
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<PAGE>
  
  (b) The parties intend that fees and expenses incurred 
by Ballard under the Engagement Letter and Losses paid or incurred 
by either party under the Indemnity Letter are to be reimbursed to 
them out of the proceeds of the consummated transaction 
contemplated in the Engagement Letter.

  (c) If the proceeds of any Transaction are not 
sufficient to cover such fees, expenses, and Losses then each shall 
have a right of contribution against the other for such fees, 
expenses, and Losses in order to achieve the following:

   (i) All Losses will be allocated and shared in 
proportion to the relative amount of Net proceeds received by the 
Company (i.e., the Management Team) and Ballard.

   (ii) All fees and expenses under the Engagement 
Letter shall be paid solely by Ballard.

  (d) If no Transaction is consummated, then each shall 
have a right of contribution against the other for any such fees, 
expenses, and Losses in order to achieve the following:

   (i) All Losses will be allocated and shared in 
proportion to the relative fault of the Company and Ballard as 
determined by a court of competent jurisdiction, if any.  If 
neither party is at fault, then such Losses shall be allocated and 
shared equally.

   (ii) All fees and expenses under the Engagement 
Letter shall be paid solely by Ballard.

  6. Relationship.  The parties do not intend to be and are 
not partners or joint venturers.

  7. Notices.  Except as otherwise provided, all notices and 
other communications which are required or permitted hereunder 
shall be in writing and sufficient if delivered personally or sent 
by a nationally recognized overnight express carrier for next-day 
delivery (charges prepaid) or by registered or certified mail, 
postage prepaid, addressed as follows:

 If to Ballard:    Ballard Medical Products
                   12050 Lone Peak Parkway
                   Draper, Utah 84020
                   Attention: Dale H. Ballard, President

                               18 of 29
<PAGE>
      
If to the Company:   Neuro Navigational Corporation
                     3180 Pullman Street
                     Costa Mesa, California 92626
                     Attention: William J. Worthen, President

  8. Governing Law.  This Agreement shall be governed by and 
construed in accordance with the laws of the State of Utah 
applicable to agreements made and entirely to be performed within 
such jurisdiction except to the extent federal law may be appli-
cable.  Any action under this Agreement filed by the Company (other 
than a counterclaim in a pending proceeding) may be filed and 
maintained only in state or federal courts located within Salt Lake 
County, State of Utah, and all parties hereby submit to the 
jurisdiction of such courts for such purposes.  Any counterclaims 
related to such suits shall also be litigated in Salt Lake County. 
Any actions filed by Ballard (other than a counterclaim in a 
pending proceeding) may be filed and maintained only in state or 
federal courts located within Orange County, State of California.  
Any counterclaims relating to such suits shall also be litigated in 
Orange County.

  9. Litigation Expenses, Remedies.  If any action, suit or 
proceeding is brought by a party hereto with respect to a matter or 
matters covered by this Agreement, all costs and expenses of the 
prevailing party incident to such proceeding, including reasonable 
attorney's fees, shall be paid by the other party.  If either party 
breaches this Agreement, the other party shall have the right, in 
addition to its other rights and remedies available at law and in 
equity, to seek equitable remedies, such as specific performance 
and injunction.

 10. Successors in Interest.  This Agreement shall be binding 
upon and inure to the benefit of the successors and assigns of the 
parties hereto.

 11. Waiver and Modification.  This Agreement may not be 
amended, modified, superseded or canceled, and none of the terms, 
covenants, representations, warranties and conditions, may be 
waived except by written instrument executed by the Company and 
Ballard; or, in the case of a waiver, by the party waiving 
compliance.  Failure of any party at any time or times to require 
strict performance of any provision hereof shall not in any manner 
affect the right of such party at a later date to enforce the same. 
 No waiver by any party of the breach of any term, covenant, 
representation or warranty contained in this Agreement as a 
condition to such party's obligations hereunder, shall constitute a 
release or affect any liability resulting from said breach.

                               19 of 29
<PAGE>
      
12. Exhibits.  All exhibits attached to this Agreement are 
expressly made a part of this Agreement as fully as if completely 
set forth in it.  All references to this Agreement, either in the 
Agreement itself or in any of such writings, shall deem to refer to 
and include this Agreement, and all such exhibits.

 13. Execution by Facsimile and Counterpart.  Signatures sent 
via facsimile transmission shall constitute original signatures.  
The parties may execute counterpart originals of this Agreement.  
This Agreement may be executed separately or independently in any 
number of counterparts, each and all of which together shall be 
deemed to have been executed simultaneously and for all purposes to 
be one Agreement.

 14. Captions.  The respective captions of the sections and 
paragraphs of this Agreement are inserted for convenience of 
reference only and shall not be deemed to modify or otherwise 
affect in any respect the provisions of this Agreement.

 IN WITNESS WHEREOF, the parties hereto have caused this 
Agreement to be executed as of the day and year first above 
written.

BALLARD MEDICAL PRODUCTS

By:  _________________________                                                
     Dale H. Ballard, President


THE COMPANY:

NEURO NAVIGATIONAL CORPORATION

By:  _____________________________                     
     William J. Worthen, President

                               20 of 29
<PAGE>


                             EXHIBIT A

       May 7, 1996 
 
 
Neuro Navigational Corporation 
3180 Pullman Street 
Costa Mesa, CA  92626 
 
Attention: William J. Worthen 
  President and Chief Executive Officer 
 
Ballard Medical Products 
12050 Lone Peak Parkway 
Draper, UT  84020 
 
Attention: Dale H. Ballard 
  Chairman, President and Chief Executive Officer 
 
Gentlemen:  
 
 (I) This is to confirm our understanding that Vector Securities 
 International, Inc. ("Vector") has  been engaged as exclusive financial 
 advisor of Ballard Medical Products ("Ballard") and Neuro Navigational  
 Corporation (the "Company") (both companies are hereinafter collectively 
 referred to as the "Parties") for a period  of one year commencing with the 
 Parties' acceptance of this agreement (the "Initial Period") for the purpose 
 of  assisting the Parties' in conducting discussions and negotiations 
 leading to:  (i) the consummation of a sale of  greater than a majority of 
 the business, assets, or stock of the Company which sale might also involve 
 the sale of all  or a portion of Ballard's option to purchase the Company 
 (the "Ballard Option"); and/or (ii) the consummation of  one or more 
 Strategic Alliance (as described in Paragraph IV below) or similar 
 transactions involving less than a majority of the business, assets, or 
 stock of the Company.  In its role as exclusive financial advisor, Vector 
 will  assist the Parties in: (a) identifying prospective acquirors or 
 partners; (b) preparing appropriate marketing  materials; (c) conducting 
 discussions and negotiations looking toward the consummation of one 
 or more  transaction(s); and (d) if requested by the Parties, providing, in 
 accordance with our customary practice, an opinion  (the "Opinion") to the 
 Board of Directors of Ballard with respect to the adequacy or fairness, from 
 a financial point  of view, to Ballard and its shareholders, of the 
 consideration to be paid in a Sale (as defined below), it being  understood 
 that the Opinion shall be in such form as Vector shall determine and Vector 
 may qualify the Opinion in  such manner as Vector believes appropriate.  The 
 Opinion shall not address Ballard's underlying business decision  to effect a 
 Sale.  Vector's engagement hereunder may be extended for additional periods 
 under the terms set forth  herein upon the mutual written agreement of Vector 
 and the Parties.  This Initial Period and any extensions thereof  are 
 hereinafter referred to as the "Engagement Period." 
 
 (II)  The Parties will pay a non-refundable retainer fee of $125,000, such 
 fee to be payable in cash  promptly upon the execution of this agreement.  
 Such retainer fee will be credited against any additional fees paid to Vector 
 pursuant to paragraphs (V) or (VI) this agreement.  The Parties also agree 
 to pay all of our reasonable  out-of-pocket expenses up to a maximum of 
 $20,000 (the "Expense Cap"), including fees and disbursements of our  
 counsel; such expenses to be paid in cash upon submission of a bill or bills 
 by us from time to time.  Vector agrees that it will not make any 
 expenditures in excess of the Expense Cap without the Parties' prior written 
 approval,  which approval will not be unreasonably withheld.      

                               21 of 29
<PAGE>
  

 (III) In addition to the fees provided in paragraph (II) above, the Parties 
 will pay Vector a fee of  $250,000 upon the date on which Vector advises 
 Ballard that it is prepared to deliver the Opinion. Such opinion  fee shall 
 be credited against any additional fees paid to Vector pursuant to 
 paragraphs (V) or (VI) of this Agreement. 
 
 (IV) Vector will conduct such financial review of the Company and its 
 businesses and operations as  Vector deems necessary and feasible for 
 purposes of rendering the Opinion.  Such review will be based upon an  
 analysis of publicly available information and such other information as 
 shall be supplied to Vector by the Parties.   Vector is not assuming any 
 responsibility for making or obtaining an independent valuation or appraisal 
 of the  assets or liabilities of the Company or any other entity.  
 
 (V) If a sale, merger, consolidation, tender offer, business combination or 
 similar transaction  involving greater than a majority of the business, 
 assets, or stock of the Company, including a sale of any option or  right to 
 acquire a majority of the business, assets or stock of the Company 
 (a "Sale") is entered into or consummated (i) within the Engagement Period 
 with any party, or (ii) not later than one year after the expiration  of 
 such Engagement Period with a party (or any entity controlled by or 
 affiliated with such party) identified by  Vector in writing and 
 acknowledged by Ballard (which shall include those parties contacted by 
 Vector on behalf of  the Parties prior to the end of the Engagement Period)
 then Vector will be paid a fee equal to the greater of  $500,000 or 5% of 
 the aggregate consideration to be paid by the acquiror or its shareholders 
 in such transaction, such fee to be payable in cash promptly upon the 
 closing of such transaction.  In the event that the Sale is  consummated 
 through more than one closing or with more than one acquiror, the Parties 
 agree that the aggregate  consideration used to calculate Vector's fee 
 hereunder shall be the sum total of the aggregate consideration paid or to 
 be paid in each such closing by each such acquiror.  For the purpose of 
 calculating our fee under this Paragraph  (III), the aggregate consideration 
 paid with respect to the business, assets, stock, options, warrants or 
 other  securities of the Company or the Ballard Option shall be equal to the 
 total of all cash, assets, stock, options,  warrants or other securities 
 paid by the acquiror.  Aggregate consideration shall also include: (a) any 
 commercial  bank, capital lease obligations or other indebtedness that is 
 repaid or for which the responsibility to pay is assumed  by the acquiror in 
 connection with the Sale; (b) the greater of the stated value or the 
 liquidation value of preferred  stock that is assumed or acquired by the 
 acquiror that is not converted into common stock upon the consummation  
 of such transaction; and (c) future payments for which the acquiror is 
 obligated either absolutely or upon the  attainment of milestones, financial 
 results, or other future events ("Acquiror Future Payments").  The fee paid 
 to  Vector as a result of Acquiror Future Payments shall be paid when such 
 Acquiror Future Payments are made.  It is  further understood that aggregate 
 consideration shall not be reduced by the amount of the fee due Vector 
 hereunder.  For the purpose of calculating our fee, securities constituting 
 part of aggregate consideration that are  traded on a national securities 
 exchange or the Nasdaq National Market shall be valued at the last closing 
 price thereof prior to the date of the consummation or closing of any 
 such transaction.  Such securities which are traded over-the-counter shall 
 be valued at the mean between the latest bid and asked prices prior to such 
 date.  Any debt or other securities of the acquiror shall be valued at their 
 fair market value.  In the event a Sale is consummated through a multiple-step
 transaction wherein the  acquiror is obligated either absolutely or upon the
 attainment of milestones,  financial results, or other future events to make 
 future payments to further  increase its ownership in the  Company (the 
 "Acquiror Multiple-Step  Payments"), the Parties agree to pay Vector a fee
 on such Acquiror  Multiple-Step Payments, and such fee shall be calculated
 pursuant to this paragraph (III).  Such fee shall be payable when such
 Acquiror Multiple-Step  Payments are made and shall be in addition to the
 fee paid to Vector in the earlier step(s) of such transaction.  
                              
                               22 of 29
<PAGE>
                                                          
 (VI) If an agreement for a Strategic Alliance is entered into or 
 consummated (i) within the  Engagement Period with any party, or (ii) not 
 later than one year after the termination of such Engagement Period  with a 
 party (or any entity controlled by or affiliated with such party) identified 
 by Vector in writing and  acknowledged by Ballard (which shall include those 
 parties contacted by Vector on behalf of the Parties prior to the  end of 
 the Engagement Period) Vector will be paid a fee equal to the greater of 
 $500,000 or 5% of the aggregate  consideration to be paid by the Partner in 
 each such transaction, such fee to be payable in cash at the time of the  
 closing of each such Strategic Alliance.  The type of transaction 
 contemplated by a Strategic Alliance will include,  but is not limited to: 
 (i) a joint venture, partnership, license or other contract or agreement 
 relating to the  development, manufacturing, marketing, distribution, sale 
 or other activity relating to the Company's present or  future products, 
 services, technology or the like; (ii) the purchase or commitment by the 
 Partner to purchase less  than a majority of the business, assets or stock 
 of the Company; (iii) the sale of any rights in respect to the  Company's 
 products, services, technologies or the like; and (iv) a commitment 
 to provide funding for all or part of  the Company's research and development
 activities.  For the purpose of calculating our fee hereunder, aggregate  
 consideration shall include, but not be limited to: (a) all payments made at 
 closing for equity securities, equity  security rights or similar rights; 
 (b) technology access fees, licensing fees or other up-front payments; (c) 
 other  future payments for which the Partner is obligated either absolutely 
 or upon the attainment of milestones, financial  results or other future 
 events; (d) funding by the Partner (through reimbursement or otherwise) 
 relative to research  and development, clinical trials, regulatory approvals  
 and related expenditures, whether such work is performed or  managed by the 
 Company or the Partner; and (e) the repayment or assumption by the Partner 
 of obligations of the  Company or Ballard including indebtedness for money 
 borrowed or amounts owed to inventors or owners of technology.  The fee paid 
 to Vector as the result of any future rights, commitments, contingent 
 payments and the  like (together, "Strategic Alliance Future Payments") 
 which are part of the consideration, shall be paid when such Strategic 
 Alliance Future Payments are made.  For purpose of this agreement, Strategic 
 Alliance shall not include,  and Vector shall not be entitled to a fee under 
 this paragraph VI with respect to, financing for which Vector does  not 
 provide assistance raised by William J. Worthen, Ballard, and other 
 shareholders solely for the financing of a  venture to develop 
 interventional radiology and reproductive medicine applications of certain 
 of the Company's technology.  
 
 (VII) Although a number of the references herein relate to a transaction 
 with the Company, including a  possible Sale of or Strategic Alliance with 
 the Company, it is the Parties' understanding that the transaction might  
 involve the purchase of the Ballard Option to purchase the Company either in 
 whole or in part.  The transaction  could also involve another form of 
 transaction relating to the Company and/or Ballard.  Regardless of the form 
 of the transaction, the Parties agree that all consideration paid to or 
 involving Ballard, the Company, or to any of their respective shareholders 
 or employees in any transaction or series of transactions involving a Sale 
 or Strategic Alliance, shall be included in the definition of aggregate 
 consideration even if a component(s) of such  consideration does not clearly 
 fall into such definition.  Specifically, the Parties agree that if a Sale 
 involves the  sale or transfer of all or a portion of the Ballard Option (i) 
 aggregate consideration shall include the consideration paid for the Ballard 
 Option and the aggregate amount payable upon the full exercise of the Ballard 
 Option (the "Exercise Price") without taking into account any reductions of, 
 or credits against, such Exercise Price (including as a result of the 
 repayment or discharge of indebtedness, the redemption of any preferred 
 stock or other securities or the crediting of any amounts previously paid 
 with respect to the Ballard Option) and (ii) the stated value or liquidation 
 value of any preferred stock that is acquired in such Sale and redeemed in 
 connection with the exercise  of the Ballard Option shall not be added to 
 aggregate consideration.  Ballard and the Company agree to be jointly and 
 severally liable for the payment of Vector's fees and the reimbursement of 
 Vector's expenses hereunder.  

                               23 of 29
<PAGE>
 
 (VIII) In order to coordinate the efforts to effect a transaction 
 satisfactory to the Parties during the Engagement Period, in the event that 
 the Company or Ballard or any of their directors, management or shareholders 
 receive any meaningful inquiry or are otherwise aware of the interest of any 
 third party concerning  any transaction as contemplated in this agreement, 
 such party agrees to promptly inform Vector of the third party and its 
 interest and request that Vector perform its services as contemplated 
 hereunder.  Vector hereby acknowledges that the Parties have no obligation 
 under this letter agreement to proceed with any potential transaction 
 presented to them by Vector. 
 
 (IX) Any financial advice rendered by us pursuant to this agreement 
 (including any Opinion) may not  be disclosed publicly in any manner without 
 our prior written approval, except as required by law, and will be treated 
 by us as confidential.  The Parties will provide us with all financial and 
 other information requested by us  for the purposes of rendering our 
 services pursuant to this agreement, and shall provide Vector with 
 reasonable  access to the Parties' officers, directors, employees, 
 independent accountants and other advisors and agents as  Vector shall deem 
 appropriate.  The Parties represent that all information furnished by them 
 or on their behalf to  Vector will be accurate and complete in all material
 respects.  The Parties recognize and confirm that, in advising the Parties 
 and in completing its engagement hereunder, Vector will be using and relying 
 on publicly available  information and on data, material, and other 
 information furnished to Vector by the Parties and other parties.  It is
 understood that in performing under this engagement Vector may assume and 
 rely upon the accuracy and completeness of, and is not assuming any 
 responsibility for independent verification of, such publicly available  
 information and the other information so furnished. 
 
 (X) All non-public information given us by the Parties will be treated by us 
 as confidential.  We may  rely, without independent verification, on the 
 accuracy and completeness of all information furnished to us by the Parties 
 or any other party or potential party to any transaction contemplated 
 hereunder. 
 
 (XI) Since Vector will be acting on behalf of the Parties in connection with 
 its engagement hereunder,  the Parties and Vector have entered into a 
 separate letter agreement, dated the date hereof, providing for the 
 indemnification by the Parties of Vector and certain related entities.  A 
 copy of such letter agreement is attached to this letter.   
 
 (XII) It is understood and agreed that Vector and its affiliates may from 
 time to time make a market in, have a long or short position in, buy and
 sell or otherwise effect transactions for customer accounts and for their 
 own accounts in the securities of, or perform investment banking or other 
 services for, Ballard and other entities  which are or may be the subject of 
 the engagement contemplated by this Agreement.   
 
 (XIII) This Agreement may be executed in one or more counterparts, each of 
 which shall be deemed an original and all of which together shall constitute 
 one and the same agreement.  Please confirm that the foregoing is in 
 accordance with your understanding by signing and returning to us the 
 enclosed duplicate of this letter.  
 
                               24 of 29
<PAGE>

Vector Securities International, Inc.
May 7, 1996
Page 5







Sincerely yours, 
 
 VECTOR SECURITIES INTERNATIONAL, INC. 
 
 
  
 By:   
  W. Gregory Shearer 
  Managing Director 
 
Confirmed as of the date hereof: 
 
NEURO NAVIGATIONAL CORPORATION 
 
 
 
By:   
 William J. Worthen 
 President and Chief Executive Officer 
 
 
BALLARD MEDICAL PRODUCTS 
 
 
 
By:   
 Dale H. Ballard 
 Chairman, President and Chief Executive Officer 
 
 
                               25 of 29
<PAGE>

 
                             EXHIBIT B
 
 
  May 7, 1996 
 
 
 Vector Securities International, Inc.  
 1751 Lake Cook Road, Suite 350  
 Deerfield, Illinois 60015 
 
 Gentlemen: 
 
 In connection with your engagement by us as set forth in the engagement
 letter dated the date hereof (the  "Engagement Letter"), we jointly and 
 severally hereby agree to indemnify and hold harmless you and your 
 affiliates, the respective directors, officers, stockholders, agents and 
 employees of you and your affiliates and each  other person, if any, 
 controlling you or any of your affiliates (collectively referred to as 
 "you" and "your"), to the  full extent lawful, from and against all losses, 
 claims, damages, liabilities and expenses (collectively, "Losses") in-curred 
 by you (including fees and disbursements of counsel) which (i) are related 
 to or arise out of actions taken or  omitted to be taken (including any
 untrue statements made or any statements omitted to be made) by us or by you  
 with our consent or in conformity with our actions or omissions or (ii) are 
 otherwise related to or arise out of your  activities on our behalf in 
 connection with your engagement by us, and we will reimburse you for all 
 expenses (including fees and disbursements of counsel) as they are incurred 
 by you in connection with investigating,  preparing or defending any such 
 action or claim, whether or not in connection with pending or threatened 
 litigation in which you are a party.  We will not be responsible, however, 
 for any Losses pursuant to clause (ii) of the preceding sentence to the 
 extent such losses are finally judicially determined to have resulted from 
 your willful  misfeasance or gross negligence.  We also agree that you shall 
 not have any liability to us for or in connection with such engagement 
 except to the extent of Losses incurred by us which are finally judicially 
 determined to have  resulted from your willful misfeasance or gross 
 negligence.  We further agree that we will not, without the prior written 
 consent of Vector Securities International, Inc. ("Vector"), settle or 
 compromise or consent to the entry of  any judgment in any pending or 
 threatened claim, action, suit or proceeding in respect of which 
 indemnification  may be sought hereunder (whether or not you are an actual 
 or potential party to such claim, action, suit or proceeding) unless such 
 settlement, compromise or consent includes an unconditional release of you 
 from all liability arising out of such claim, action, suit or proceeding.  
 Payments pursuant to this paragraph shall be paid by us promptly upon our 
 receipt of a statement(s) from Vector setting forth the amounts with respect 
 to which indemnification and/or reimbursement is sought pursuant to this 
 paragraph. 
 
 We agree if any indemnification sought by you pursuant to this letter 
 agreement is unavailable or insufficient to hold you harmless, then (whether 
 or not Vector is the indemnified person), we and Vector will contribute to 
 the  Losses for which such indemnification is unavailable or insufficient in 
 such proportion as is appropriate to reflect the relative benefits to, and 
 the relative fault of, us, on the one hand, and Vector, on the other hand, 
 in connection  with Vector's engagement referred to above, subject to the 
 limitation that in any event Vector's aggregate contribution to all Losses 
 with respect to which contribution is available hereunder will not exceed 
 the amount of  fees actually received by Vector from us pursuant to Vector's 
 engagement referred to above.  Our obligations pursuant to this paragraph 
 will also be joint and several.   
 
                               26 of 29
<PAGE> 
 
 Vector Securities International, Inc. 
 May 7, 1996 
 Page 2 
 
 
 
 Our indemnity, reimbursement and contribution obligations under this letter 
 agreement shall be in addition  to any rights that you may have at common 
 law or otherwise.  We hereby consent to personal jurisdiction and  service 
 and venue in any court in which any claim which is subject to this letter 
 agreement is brought against you.  This letter agreement shall be governed 
 by and construed in accordance with the laws of the State of Illinois 
 without regard to principles of conflicts of laws.  Any right to trial by 
 jury with respect to any claim or proceeding related to or arising out of 
 Vector's engagement by us or this agreement is waived.  This letter 
 agreement may be executed in one or more counterparts, each of which shall 
 be deemed an original and all of which shall constitute  one and the same 
 agreement. 
 
 It is understood that, in connection with Vector's above-mentioned 
 engagement, Vector may also be engaged  to act in one or more additional 
 capacities, and that the terms of the original engagement or any such 
 additional  engagement may be embodied in one or more separate written 
 agreements.  The provisions of this letter agreement shall apply to the 
 original engagement, any such additional engagement(s) and any modification 
 of the original engagement or such additional engagement(s) and shall remain 
 in full force and effect following the completion of termination of Vector's 
 engagement(s). 
 
 
  Very truly yours, 
 
  NEURO NAVIGATIONAL CORPORATION 
 
 
 
  By:      
   William J. Worthen 
   President and Chief Executive Officer 
 
 
  BALLARD MEDICAL PRODUCTS 
 
 
 
  By:      
   Dale H. Ballard 
   Chairman, President and Chief Executive Officer 
 
 
 Accepted: 
 
 VECTOR SECURITIES INTERNATIONAL, INC. 
 
 
 By: ____________________________________ 
 W. Gregory Shearer 
 Managing Director 
 
 Date: __________________________________,  1996 
  
                              27 of 29
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                    EXHIBIT C

                   Distribution

Name                 Percent

Bill Worthen          31.56
Brett Scott            7.69
Derek Daw              7.69
George Acosta          7.69
William Rigas          7.69
Thomas Whitehair       7.69
Bob Hill               7.69
Karen Salinas          7.69
John Aoki              1.29
Lance Kumm             0.76
John Brustad           2.00
Hoa Vo                 0.38
Julia Goodkind         1.55
Sharon Nagakoa         0.78
Steven Karas           0.96
Charles Schubert       0.67
Victoria Connor        0.29
Carlene Denotto        0.29
Nadine Pettit          0.96
Roza Sturm             1.10
Marcie Kim             0.10
Dorota Kochmanski      1.10
Michael                0.14
Julie Fralick          1.43
Bill Wooten            0.14
Rene Harrison          0.19
Anne Amelung           0.48
   Total             100.00
 
                               28 of 29
<PAGE>