|EXHIBIT 10.3
|------------

November 10, 2003

Bank
of America, N.A.,   as Administrative Agent231 South LaSalle StreetMail
Code: IL1-231-08-03Chicago, IL 60604Attn: Anne Zeschke

|Re:   Request for Waiver and Amendment of Certain Provisions of the Fifth Amended         and Restated Loan Agreement.
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|Prime Medical Services, Inc., a
Delaware corporation (Company), certain Lenders (the
Lenders), and Bank of America, N.A., as Administrative
Agent for those Lenders (Administrative Agent), have
entered into that certain Fifth Amended and Restated Loan Agreement (as renewed, extended,
restated, and amended from time to time, the Loan
Agreement) dated as of July 26, 2002. Under the terms of certain
Guaranties (for each Guarantor defined below, the
Guaranty), certain of the
Subsidiaries (as defined in the Loan Agreement) of
Company (collectively, the Guarantors) have guaranteed
payment of the Guaranteed Indebtedness (as defined in the
Guaranty). Unless otherwise specified (i) capitalized terms used herein shall have
the same meanings as set forth in the Loan Agreement and (ii) references to
Sections are to sections of the Loan Agreement. Company
hereby requests a waiver of certain terms and provisions of the Loan Agreement and
amendments to certain other terms and provisions thereof, and Company, Lenders, and
Administrative Agent have agreed to waive and amend certain provisions of the Loan
Agreement, each subject to the terms and conditions contained herein.
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|Section
1.Company Request. Company has formed a
Wholly-Owned Subsidiary of the Company for the purpose of acquiring Medstone
International, Inc., a Delaware corporation, substantially on the terms and conditions
presented to Lenders by Borrower (the Medstone Acquisition).
Company has requested that Lenders permit the Medstone Acquisition substantially in
accordance with the terms and conditions presented.
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|Company has also requested that
certain provisions of the Loan Agreement be amended to reflect an accounting change
required under Financial Accounting Standards Board Statement 150.
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|Section 2.             Waivers to Loan Agreement.  Certain provisions of the Loan Agreement shall be waived as follows:
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| | A. | In connection with the Medstone Acquisition, the requirement set forth in the
               final proviso of the definition of Permitted
               Acquisition that Borrower not make any Acquisitions other
               than Permitted Acquisitions in which the total consideration for all such
               Acquisitions is less than $2,000,000 in the aggregate in any twelve (12) month
               period is hereby waived to permit the Medstone Acquisition;
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November 10, 2003Page 2

| | B. | In connection with the Medstone Acquisition, Section 8.02
               of the Loan Agreement shall be waived to permit the Medstone Acquisition; and
| | -- | ------------------------------------------------------------------------------------------------------------------------------------------------------

| | C. | In connection with the Medstone Acquisition, Section 8.04
               of the Loan Agreement shall be waived to permit the Medstone Acquisition.
| | -- | --------------------------------------------------------------------------------------------------------------------------------------------------

|Section 3.             Amendments  to the Loan  Agreement.  By execution  of this Waiver and  Amendment,  the parties  hereto have
agreed to amend the Loan Agreement as follows:
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

A.      

          Section 1.01 is hereby amended to delete the definition of
          EBITDA in its entirety and replace such
          definition with the following:

| | EBITDA
means, for any Person for any period: (a) Consolidated Net Income of such Person for such
period, determined after deduction of any minority interests, plus (b) all amounts
deducted therefrom during such period, in conformity with GAAP, for interest, taxes,
depreciation and amortization, provided that cash flow from Permitted Passive Investments
shall only be included in the calculation of EBITDA to the extent: (i) it has been
actually received by Borrower or a Guarantor, and (ii) it does not exceed fifteen percent
(15%) of total EBITDA for such period, and provided further, that (x) the 2002
Adjustments, (y) the non-cash losses or impairments resulting from the Lasik Divesture, in
an aggregate amount not to exceed $15,000,000, not included in the calculation of 2002
Adjustments, and (z) the FASB 150 Adjustments shall be excluded from any calculation of
Borrowers EBITDA.
| | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

B.      
          Section 1.01 is hereby amended to delete the definition of
          Debt Service Coverage Ratio in its entirety and
          replace such definition with the following:

| | Debt
Service Coverage Ratio means, as to the Companies (including on a pro
forma basis any Company acquired in any Permitted Domestic Acquisition for each of the
components of and for the entire period of calculation of Debt Service Coverage Ratio) for
any period, the ratio of (a) the sum of: (i) Adjusted EBITDA for
such period, minus (ii) the aggregate amount of Unfinanced Capital Expenditures
made during such period, minus (iii) all cash tax payments, minus (iv) all
cash payments relating to the FASB 150 Adjustments, divided by (b) the sum
of: (i) all cash interest payments payable during such period in respect of all Debt
of the Companies (without deduction for any minority interests but excluding Debt of any
Foreign Company to the extent it is repaid with cash flow of such Foreign Company),
plus (ii) 1/7 of the outstanding principal amount of the Loans as of any date of
determination, plus (iii) 1/7 of the Consolidated Earn-Out Indebtedness as of any
date of determination, plus (iv) any regularly scheduled principal payments on
Indebtedness (including Subordinated Debt, but excluding Consolidated Earn-Out
Indebtedness and excluding Debt of any Foreign Company), plus (v) all cash
dividends declared or paid on any Permitted Preferred Stock, all as determined on a
rolling four (4) quarter and consolidated basis in accordance with GAAP.
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November 10, 2003Page 3

C.      
          Section 1.01 is hereby amended to add the following
          definition of FASB 150 Adjustment:

| | FASB
150 Adjustments means the non-cash adjustments to Borrowers
financial statements regarding the Robert W. Bachman and Lawrence J. Sodomire put options,
as required by Statement 150 of the Financial Accounting Standards Board, the net effect
to Borrower on a consolidated basis not to exceed $1,250,000 in an aggregate amount.
| | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

|Section 4.      Representations.The Company and each Guarantor hereby represent and warrant to Administrative Agent
and the Lenders that: (i) the representations and warranties contained in the Loan
Agreement and the other Loan Documents are true and correct on and as of the date hereof
as though made on and as of such date; (ii) after giving effect to this letter and the
waiver granted herein, neither the Company nor any of the Guarantors is in default in
the due performance of any covenant or agreement contained in the Loan Agreement or any
other Loan Document; and (iii) after giving effect to this letter and the waiver granted
herein, no Default has occurred and is continuing.
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|Section 5.      Confirmations.Each of the Company and the Guarantors ratifies and confirms that the Loan Agreement,
the Guaranties, the Borrower Security Agreement, the Guarantor Security Agreements, the
Pledge Agreements, and the other Loan Documents are and remain in full force and effect in
accordance with their respective terms, as amended hereby. In addition, each of the
Guarantors acknowledges, agrees, accepts and consents to the terms and provisions hereof
and each other Loan Document as amended hereby. Except as expressly provided herein, this
letter does not constitute a waiver or modification of any of the terms or provisions set
forth in the Loan Agreement or any other Loan Document and shall not impair any right that
Administrative Agent or the Lenders may now or hereafter have under or in connection with
the Loan Agreement or any other Loan Document.
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|Section 6.      No Impairment.The waivers hereby granted by Administrative Agent and the Required Lenders (i) does
not impair Administrative Agents or any of the Lenders rights to insist upon
strict compliance with the Loan Agreement or the other Loan Documents, and (ii) does not
extend to any other Loan Document. The Loan Documents, as waived hereby continue to bind
and inure to Administrative Agent, the Lenders, Company, the Guarantors, and their
respective successors and permitted assigns.
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Section 7.      Conditions
Precedent.

| | A. | The effectiveness of this letter and waiver agreement is subject to the
               conditions precedent that the Administrative Agent shall have received all of
               the following, in form and substance satisfactory to the Administrative Agent:
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November 10, 2003Page 4

| | (i) | No Default. No Default shall have occurred and be continuing under the
               Loan Agreement.
| | --- | -----------------------------------------------------------------------------------------------------

| | (ii) | Representations and Warranties. All of the representations and warranties
               contained in Article VII of the Loan Agreement hereof and in each of the other
               Loan Documents shall be true and correct on and as of the date hereof with the
               same force and effect as if such representations and warranties had been made on
               and as of such date, except to the extent that such representations and
               warranties speak to a specific date or the facts on which such representations
               and warranties are based have been changed by transactions contemplated by the
               Loan Documents.
| | ---- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | (iii) | Fees and Expenses. Payment of all fees and expenses of counsel for
               Administrative Agent in connection with the preparation and negotiation of this
               Amendment and Waiver.
| | ----- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | (iv) | Updating Certificate. A Certificate signed by the Chief Executive or
               Chief Financial Officer or Vice President-Treasurer of Company and the
               Guarantors setting forth any changes to the Schedules to the Loan Agreement
               since the date of execution of the Loan Agreement.
| | ---- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | B. | In addition to the conditions precedent listed in Section 7(A) above, the
               effectiveness of Section 2 of this letter and waiver
               agreement is subject to the conditions precedent that the Administrative Agent
               shall have received all of the following, in form and substance satisfactory to
               the Administrative Agent:
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| | (i) | Acquisition Agreement. A duly executed and completed acquisition
               agreement in form and content acceptable to Administrative Agent.
| | --- | -------------------------------------------------------------------------------------------------------------------------------------------------

| | (ii) | Permitted Acquisition Certificate. A duly executed and completed
               Permitted Acquisition Certificate substantially in the form of Exhibit
               I to the Loan Agreement with appropriate revisions to give effect
               to the waivers set forth herein.
| | ---- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | (iii) | Collateral Documents. Guaranties, Guarantor Security Agreements, and
               Pledge Agreements, executed and delivered by Medstone International, Inc. and
               the Company, blank stock powers, and other documents reasonably requested by
               Administrative Agent, including Articles of Incorporation duly certified by the
               Secretary of State of Delaware, by-laws, and board of directors resolutions of
               Medstone International, Inc.
| | ----- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

|Section 8.      Counterparts.This agreement, when countersigned by Company, Guarantors, Administrative Agent, and
Required Lenders shall be a Loan Document as defined and referred to in
the Loan Agreement and the other Loan Documents and may be signed in any number of
counterparts, each of which shall be deemed an original, but all of which together shall
constitute one and the same instrument. This agreement shall be governed by and construed
in accordance with the laws of the State of Texas.
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|November 10, 2003Page 5



Section 9.      Entire
Agreement.THIS AGREEMENT, THE LOAN AGREEMENT, THE NOTES AND THE OTHER LOAN DOCUMENTS
EMBODY THE FINAL, ENTIRE AGREEMENT AMONG THE PARTIES HERETO AND SUPERSEDE ANY AND ALL
PRIOR COMMITMENTS, AGREEMENTS, REPRESENTATIONS, AND UNDERSTANDINGS, WHETHER WRITTEN OR
ORAL, RELATING TO THE SUBJECT MATTER HEREOF AND MAY NOT BE CONTRADICTED OR VARIED BY
EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENTS OR DISCUSSIONS OF THE
PARTIES HERETO. THERE ARE NO ORAL AGREEMENTS AMONG THE PARTIES HERETO.
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|[REMAINDER OF PAGE
INTENTIONALLY BLANK.SIGNATURE PAGES FOLLOW.]
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|If the foregoing is agreeable to you,
please signify your acceptance of the terms and conditions set forth herein by placing
your signature in the space provided below.
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | Very truly yours,PRIME MEDICAL SERVICES, INC.,
   as Company
By: _______________________________ 
       Name:  __________________________ 
       Title:   __________________________
| | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

|Signature Page to Amendment
and Waiver Letter
|---------------------------------------------



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| | GUARANTORS:PROSTATHERAPIES, INC.
LITHOTRIPTORS, INC.
FASTSTART, INC.
NATIONAL LITHOTRIPTORS ASSOCIATION
R.R. LITHO, INC.
OHIO LITHO, INC.
MEDTECH INVESTMENT, INC.
PRIME MEDICAL OPERATING, INC.
PRIME MANAGEMENT, INC.
PRIME LITHOTRIPTER OPERATIONS, INC.
PRIME DIAGNOSTIC SERVICES, INC.
PRIME LITHOTRIPSY SERVICES, INC.
PRIME DIAGNOSTIC CORP. OF FLORIDA
SUN MEDICAL TECHNOLOGIES, INC.
PRIME PRACTICE MANAGEMENT, INC.
PRIME SERVICE CENTER, INC.
         formerly known as  Prime Cardiac Rehabilitation
         Services, Inc.ALABAMA RENAL STONE INSTITUTE, INC.
PRIME KIDNEY STONE TREATMENT, INC.
SUN ACQUISITION, INC.
EXECUTIVE MEDICAL ENTERPRISES, INC.
PRIME RVC, INC.
AK ASSOCIATES, L.L.C.
PRIME MEDICAL MANUFACTURING, LLC
PRIME REFRACTIVE MANAGEMENT, L.L.C.
ALUMINUM BODY CORPORATION
WINEMILLER COMMUNICATIONS, INC.
   each as a Guarantor

By:  _____________________________________              
      Name: ________________________________              
      Title:   ________________________________              PRIME MEDICAL MANAGEMENT, L.P.
  as a Guarantor
By:  PRIME MEDICAL OPERATING, INC.,
       a Delaware corporation, its General Partner
     By:   __________________________________              
             Name:  _____________________________              
             Title: ______________________________
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|Signature Page to Amendment
and Waiver Letter
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AGREED AND ACCEPTED as of the
date first stated above.

| | BANK OF AMERICA, N.A., as Administrative Agent
By:       _____________________________       
          Kristine Thennes
          Vice President
| | -------------------------------------------------------------------------------------------------------------------------------------------------

|Signature Page to
Amendment and Waiver Letter
|---------------------------------------------



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| | BANK OF AMERICA, N.A., as a Lender
By:       _____________________________
          Daniel H. Penkar
          Senior Vice President
| | -------------------------------------------------------------------------------------------------------------------------------------

|Signature Page to Amendment
and Waiver Letter
|---------------------------------------------



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| | BANK ONE, NA, with its main office in Chicago, Illinoisas a Lender
By:   __________________________________                    
       Name: _____________________________                                           
       Title:   _____________________________
| | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

|Signature Page to Amendment
and Waiver Letter
|---------------------------------------------



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| | LASALLE BANK, NATIONAL ASSOCIATION,as a Lender
By:   __________________________________                    
       Name: _____________________________                                           
       Title:   _____________________________
| | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

|Signature Page to Amendment
and Waiver Letter
|---------------------------------------------



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| | COMERICA BANK,as a Lender
By:   __________________________________                    
       Name: _____________________________                                           
       Title:   _____________________________
| | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

|Signature Page to Amendment
and Waiver Letter
|---------------------------------------------