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                                                                  EXHIBIT 4.4(a)


                  The security represented by this certificate was originally
                  issued on May 7, 1999, and has riot been registered under the
                  Securities Act of 1933, as amended. The transfer of such
                  security is subject to the conditions specified in the Bridge
                  Loan Agreement, dated of even date herewith (as amended and
                  modified from time to time), between the issuer hereof (the
                  "Company") and the initial holder hereof, and the Company
                  reserves the right to refuse the transfer of such security
                  until such conditions have been fulfilled with respect to such
                  transfer. Upon written request, a copy of such conditions
                  shall be furnished by the Company to the holder hereof without
                  charge.

                          ALLIANCE MEDICAL CORPORATION

                             STOCK PURCHASE WARRANT

             Date of Issuance: May 7, 1999 Certificate No. W -______

         This Warrant is being issued simultaneously with the issuance of 62,500
shares of the Company's Common Stock (the "Common Stock"), represented by stock
certificate no. ___ (the "Subject Shares"), to Marquette Venture Partners III,
L.P. pursuant to the Bridge Loan Agreement dated as of the date hereof (the
"Loan Agreement"), between Alliance Medical Corporation, a Delaware corporation
(the "Company"), and certain investors.

         For value received, the Company hereby grants to Marquette Venture
Partners III, L.P. or its registered assigns (the "Registered Holder") the right
to purchase from the Company a number of shares of the Company's Common Stock at
a price per share equal to $2.00 (such price as adjusted and readjusted from
time to time in accordance with Section 2 hereof, the "Exercise Price")

         This Warrant is one of several warrants (collectively, the "Warrants")
issued pursuant to the Loan Agreement, and certain capitalized terms used herein
are defined in Section 5 hereof. The amount and kind of securities obtainable
pursuant to the rights granted hereunder and the purchase price for such
securities are subject to adjustment pursuant to the provisions contained in
this Warrant.

         For income tax purposes, the value of this Warrant as of the date
hereof is $0.10.

         This Warrant is subject to the following provisions:

         Section 1.  Exercise of Warrant.

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                  1A. Exercise Period. The Registered Holder may exercise, in
whole or in part, the purchase rights represented by this Warrant at any time
and from time to time after the Date of Issuance until the fifth anniversary of
the date hereof (the "Exercise Period").

                  1B. Exercise Procedure.

                  (i) This Warrant shall be deemed to have been exercised when
the Company has received all of the following items (the "Exercise Time"):

                  (a) a completed Exercise Agreement, as described in Section 1C
         below, executed by the Person exercising all or part of the purchase
         rights represented by this Warrant (the "Purchaser")

                  (b) this Warrant;

                  (c) if this Warrant is not registered in the name of the
         Purchaser, an Assignment or Assignments in the form set forth in
         Exhibit II hereto evidencing the assignment of this Warrant to the
         Purchaser, in which case the Registered Holder shall have complied with
         the provisions set forth in Section 7 hereof; and

                  (d) either (1) a check payable to the Company in an amount
         equal to the product of the Exercise Price multiplied by the number of
         shares of Common Stock being purchased upon such exercise (the
         "Aggregate Exercise Price"), or (2) a written notice to the Company
         that the Purchaser is exercising the Warrant (or a portion thereof) by
         authorizing the Company to withhold from issuance a number of shares of
         Common Stock issuable upon such exercise of the Warrant which when
         multiplied by the Market Price of the Common Stock is equal to the
         Aggregate Exercise Price (and such withheld shares shall no longer be
         issuable under this Warrant). For the purposes of this subsection and
         in the event that the Common Stock is not publicly traded, the Market
         Price of the Common Stock shall be determined in good faith by the
         Board of Directors of the Company.

                  (ii) Certificates for shares of Common Stock purchased upon
exercise of this Warrant shall be delivered by the Company to the Purchaser
within five business days after the date of the Exercise Time. Unless this
Warrant has expired or all of the purchase rights represented hereby have been
exercised, the Company shall prepare a new Warrant, substantially identical
hereto, representing the rights formerly represented by this Warrant which have
not expired or been exercised and shall, within such five-day period, deliver
such new Warrant to the Person designated for delivery in the Exercise
Agreement.

                  (iii) The Common Stock issuable upon the exercise of this
Warrant shall be deemed to have been issued to the Purchaser at the Exercise
Time, and the Purchaser shall be deemed for all purposes to have become the
record holder of such Common Stock at the Exercise Time.


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                  (iv) The issuance of certificates for shares of Common Stock
upon exercise of this Warrant shall be made without charge to the Registered
Holder or the Purchaser for any issuance tax in respect thereof or other cost
incurred by the Company in connection with such exercise and the related
issuance of shares of Common Stock. Each share of Common Stock issuable upon
exercise of this Warrant shall, upon payment of the Exercise Price therefor, be
fully paid and nonassessable and free from all liens and charges with respect to
the issuance thereof.

                  (v) The Company shall not close its books against the transfer
of this Warrant or of any share of Common Stock issued or issuable upon the
exercise of this Warrant in any manner which interferes with the timely exercise
of this Warrant, except as required in order to comply with applicable federal
and state securities laws. The Company shall from time to time take all such
action as may be necessary to assure that the par value per share of the
unissued Common Stock acquirable upon exercise of this Warrant is at all times
equal to or less than the Exercise Price then in effect.

                  (vi) The Company shall assist and cooperate with any
Registered Holder or Purchaser required to make any governmental filings or
obtain any governmental approvals prior to or in connection with any exercise of
this Warrant (including, without limitation, making any filings required to be
made by the Company), except that this subsection (vi) will not require the
Company to register the sale of the Common Stock underlying this Warrant under
any federal or state securities laws.

                  (vii) Notwithstanding any other provision hereof, if an
exercise of any portion of this Warrant is to be made in connection with a
registered public offering or the sale of the Company, the exercise of any
portion of this Warrant may, at the election of the holder hereof, be
conditioned upon the consummation of the public offering or sale of the Company
in which case such exercise shall not be deemed to be effective until the
consummation of such transaction.

                  (viii) The Company shall at all times reserve and keep
available out of its authorized but unissued shares of Common Stock solely for
the purpose of issuance upon the exercise of the Warrants, such number of shares
of Common Stock issuable upon the exercise of all outstanding Warrants. All
shares of Common Stock which are so issuable shall, when issued, be duly and
validly issued, fully paid and nonassessable and free from all taxes, liens and
charges. The Company shall take all such actions as may be necessary to assure
that all such shares of Common Stock may be so issued without violation of any
applicable law or governmental regulation or any requirements of any domestic
securities exchange upon which shares of Common Stock may be listed (except for
official notice of issuance which shall be immediately delivered by the Company
upon each such issuance). The Company shall not take any action which would
cause the number of authorized but unissued shares of Common Stock to be less
than the number of such shares required to be reserved hereunder for issuance
upon exercise of the Warrant.

                  (ix) If the shares of Common Stock issuable by reason of
exercise of this Warrant are convertible into or exchangeable for any other
stock or securities of the Company, the Company shall, at the exercising
holder"s option and upon surrender of this Warrant by such holder as


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provided above together with any notice, statement or payment required to effect
such conversion or exchange of Common Stock, deliver to such holder (or as
otherwise specified by such holder) a certificate or certificates representing
the stock or securities into which the shares of Common Stock issuable by reason
of such conversion are convertible or exchangeable, registered in such name or
names and in such denomination or denominations as such holder has specified.

                  1C. Exercise Agreement. Upon any exercise of this Warrant, the
Exercise Agreement shall be substantially in the form set forth in Exhibit I
hereto, except that if the shares of Common Stock are not to be issued in the
name of the Person in whose name this Warrant is registered, the Exercise
Agreement shall also state the name of the Person to whom the certificates for
the shares of Common Stock are to be issued, and if the number of shares of
Common Stock to be issued does not include all the shares of Common Stock
purchasable hereunder, it shall also state the name of the Person to whom a new
Warrant for the unexercised portion of the rights hereunder is to be delivered.
Such Exercise Agreement shall be dated the actual date of execution thereof.

                  Section 2. Adjustment of Exercise Price and Number of Shares.
In order to prevent dilution of the rights granted under this Warrant, the
Exercise Price shall be subject to adjustment from time to time as provided in
this Section 2, and the number of shares of Common Stock obtainable upon
exercise of this Warrant shall be subject to adjustment from time to time as
provided in this Section 2.

         2A. Adjustment of Exercise Price and Number of Shares upon Issuance of
Common Stock.

                  (i) If and whenever on or after the Date of Issuance of this
Warrant the Company issues or sells, or in accordance with Section 2B is deemed
to have issued or sold, any shares of Common Stock for a consideration per share
less than the Exercise Price in effect immediately prior to such time, then
immediately upon such issue or sale the Exercise Price shall be reduced to the
Exercise Price determined by dividing:

         (A)      the sum of (x) the product derived by multiplying the Exercise
                  Price in effect immediately prior to such issue or sale times
                  the number of shares of Common Stock Deemed Outstanding
                  immediately prior to such issue or sale, plus (y) the
                  consideration, if any, received by the Company upon such issue
                  or sale, by

         (B)      the number of shares of Common Stock Deemed Outstanding
                  immediately after such issue or sale.

Upon each such adjustment of the Exercise Price hereunder, the number of shares
of Common Stock acquirable upon exercise of this Warrant shall be adjusted to
the number of shares determined by multiplying the Exercise Price in effect
immediately prior to such adjustment by the number of shares of Common Stock
acquirable upon exercise of this Warrant immediately prior to such adjustment
and dividing the product thereof by the Exercise Price resulting from such
adjustment.


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                  (ii) Notwithstanding the foregoing, there shall be no
adjustment to the Exercise Price or the number of shares of Common Stock
obtainable upon exercise of this Warrant with respect to the issuance of any
securities as contemplated by the Capitalization Schedule attached as Exhibit
III hereto and the granting or repricing of stock options as contemplated by the
term sheet between Marquette Venture Partners III, L.P. and the Company attached
as Exhibit IV hereto.

                  2B. Effect on Exercise Price of Certain Events. For purposes
of determining the adjusted Exercise Price under Section 2A, the following shall
be applicable:

                  (i) Issuance of Rights or Options. If the Company in any
manner grants or sells any Options and the price per share for which Common
Stock is issuable upon the exercise of such Options, or upon conversion or
exchange of any Convertible Securities issuable upon exercise of such Options,
is less than the Exercise Price in effect immediately prior to the time of the
granting or sale of such Options, then the total maximum number of shares of
Common Stock issuable upon the exercise of such Options, or upon conversion or
exchange of the total maximum amount of such Convertible Securities issuable
upon the exercise of such Options, shall be deemed to be outstanding and to have
been issued and sold by the Company at such time for such price per share. For
purposes of this Section, the "price per share for which Common Stock is
issuable upon exercise of such Options or upon conversion or exchange of such
Convertible Securities" is determined by dividing (A) the total amount, if any,
received or receivable by the Company as consideration for the granting or sale
of such Options, plus the minimum aggregate amount of additional consideration
payable to the Company upon the exercise of all such Options, plus in the case
of such Options which relate to Convertible Securities, the minimum aggregate
amount of additional consideration, if any, payable to the Company upon the
issuance or sale of such Convertible Securities and the conversion or exchange
thereof, by (B) the total maximum number of shares of Common Stock issuable upon
exercise of such Options or upon the conversion or exchange of all such
Convertible Securities issuable upon the exercise of such Options. No further
adjustment of the Exercise Price shall be made upon the actual issuance of such
Common Stock or of such Convertible Securities upon the exercise of such Options
or upon the actual issuance of such Common Stock upon conversion or exchange of
such Convertible Securities.

                  (ii) Issuance of Convertible Securities. If the Company in any
manner issues or sells any Convertible Securities and the price per share for
which Common Stock is issuable upon conversion or exchange thereof is less than
the Exercise Price in effect immediately prior to the time of such issue or
sale, then the maximum number of shares of Common Stock issuable upon conversion
or exchange of such Convertible Securities shall be deemed to be outstanding and
to have been issued and sold by the Company at such time for such price per
share. For the purposes of this Section, the "price per share for which Common
Stock is issuable upon conversion or exchange thereof" is determined by dividing
(A) the total amount received or receivable by the Company as consideration for
the issue or sale of such Convertible Securities, plus the minimum aggregate
amount of additional consideration, if any, payable to the Company upon the
conversion or exchange thereof, by (B) the total maximum number of shares of
Common Stock issuable upon the conversion or exchange of all such Convertible
Securities. No further adjustment of the Exercise Price shall be made upon the
actual issue of such Common Stock upon conversion or exchange of such


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Convertible Securities, and if any such issue or sale of such Convertible
Securities is made upon exercise of any Options for which adjustments of the
Exercise Price had been or are to be made pursuant to other provisions of this
Section 2B, no further adjustment of the Exercise Price shall be made by reason
of such issue or sale.

                  (iii) Change in Option Price or Conversion Rate. If the
purchase price provided for in any Options, the additional consideration, if
any, payable upon the issue, conversion or exchange of any Convertible
Securities, or the rate at which any Convertible Securities are convertible into
or exchangeable for Common Stock changes at any time, the Exercise Price in
effect at the time of such change shall be adjusted immediately to the Exercise
Price which would have been in effect at such time had such Options or
Convertible Securities still outstanding provided for such changed purchase
price, additional consideration or changed conversion rate, as the case may be,
at the time initially granted, issued or sold and the number of shares of Common
Stock issuable hereunder shall be correspondingly adjusted. For purposes of this
Section 2B, if the terms of any Option or Convertible Security which was
outstanding as of the date of issuance of this Warrant are changed in the manner
described in the immediately preceding sentence, then such Option or Convertible
Security and the Common Stock deemed issuable upon exercise, conversion or
exchange thereof shall be deemed to have been issued as of the date of such
change; provided that no such change shall at any time cause the Exercise Price
hereunder to be increased.

                  (iv) Treatment of Expired Options and Unexercised Convertible
Securities. Upon the expiration of any Option or the termination of any right to
convert or exchange any Convertible Securities without the exercise of such
Option or right, the Exercise Price then in effect and the number of shares of
Common Stock acquirable hereunder shall be adjusted immediately to the Exercise
Price and the number of shares which would have been in effect at the time of
such expiration or termination had such Option or Convertible Securities, to the
extent outstanding immediately prior to such expiration or termination, never
been issued. For purposes of this Section 2B, the expiration or termination of
any Option or Convertible Security which was outstanding as of the date of
issuance of this Warrant shall not cause the Exercise Price hereunder to be
adjusted unless, and only to the extent that, a change in the terms of such
Option or Convertible Security caused it to be deemed to have been issued after
the date of issuance of this Warrant.

                  (v) Calculation of Consideration Received. If any Common
Stock, Options or Convertible Securities are issued or sold or deemed to have
been issued or sold for cash, the consideration received therefor shall be
deemed to be the net amount received by the Company therefor. In case any Common
Stock, Options or Convertible Securities are issued or sold for a consideration
other than cash, the amount of the consideration other than cash received by the
Company shall be the fair value of such consideration, except where such
consideration consists of securities, in which case the amount of consideration
received by the Company shall be the Market Price thereof as of the date of
receipt. In case any Common Stock, Options or Convertible Securities are issued
to the owners of the non-surviving entity in connection with any merger in which
the Company is the surviving entity the amount of consideration therefor shall
be deemed to be the fair value of such portion of the net assets and business of
the non-surviving entity as is attributable to such Common Stock, Options or
Convertible Securities, as the case may be. The fair value of any


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consideration other than cash or securities shall be determined jointly by the
Company and the Registered Holders of Warrants representing a majority of the
shares of Common Stock obtainable upon exercise of such Warrants. If such
parties are unable to reach agreement within a reasonable period of time, such
fair value shall be determined by an appraiser jointly selected by the Company
and the Registered Holders of Warrants representing a majority of the shares of
Common Stock obtainable upon exercise of such Warrants. The determination of
such appraiser shall be final and binding on the Company and the Registered
Holders of the Warrants, and the fees and expenses of such appraiser shall be
paid by the Company.

                  (vi) Treasury Shares. The number of shares of Common Stock
outstanding at any given time does not include shares owned or held by or for
the account of the Company or any Subsidiary, and the disposition of any shares
so owned or held shall be considered an issue or sale of Common Stock.

                  (vii) Record Date. If the Company takes a record of the
holders of Common Stock for the purpose of entitling them (A) to receive a
dividend or other distribution payable in Common Stock, Options or in
Convertible Securities or (B) to subscribe for or purchase Common Stock, Options
or Convertible Securities, then such record date shall be deemed to be the date
of the issue or sale of the shares of Common Stock deemed to have been issued or
sold upon the declaration of such dividend or the making of such other
distribution or the date of the granting of such right of subscription or
purchase, as the case may be.

                  2C. Subdivision or Combination of Common Stock. If the Company
at any time subdivides (by any stock split, stock dividend, recapitalization or
otherwise) one or more classes of its outstanding shares of Common Stock into a
greater number of shares, the Exercise Price in effect immediately prior to such
subdivision shall be proportionately reduced and the number of shares of Common
Stock obtainable upon exercise of this Warrant shall be proportionately
increased. If the Company at any time combines (by reverse stock split or
otherwise) one or more classes of its outstanding shares of Common Stock into a
smaller number of shares, the Exercise Price in effect immediately prior to such
combination shall be proportionately increased and the number of shares of
Common Stock obtainable upon exercise of this Warrant shall be proportionately
decreased.

                  2D. Reorganization, Reclassification, Consolidation, Merger or
Sale. Any recapitalization, reorganization, reclassification, consolidation,
merger, sale of all or substantially all of the Company's assets or other
transaction, which in each case is effected in such a way that the holders of
Common Stock are entitled to receive (either directly or upon subsequent
liquidation) stock, securities or assets with respect to or in exchange for
Common Stock is referred to herein as "Organic Change." Prior to the
consummation of any Organic Change, the Company shall make appropriate provision
(in form and substance satisfactory to the Registered Holders of the Warrants
representing a majority of the Common Stock obtainable upon exercise of all
Warrants then outstanding) to insure that each of the Registered Holders of the
Warrants shall thereafter have the right to acquire and receive, in lieu of or
addition to (as the case may be) the shares of Common Stock immediately
theretofore acquirable and receivable upon the exercise of such holder's
Warrant, such shares of stock, securities or assets as may be issued or payable
with respect to or in exchange


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for the number of shares of Common Stock immediately theretofore acquirable and
receivable upon exercise of such holders Warrant had such Organic Change not
taken place. In any such case, the Company shall make appropriate provision (in
form and substance satisfactory to the Registered Holders of the Warrants
representing a majority of the Common Stock obtainable upon exercise of all
Warrants then outstanding) with respect to such holders' rights and interests to
insure that the provisions of this Section 2 and Sections 3 and 4 hereof shall
thereafter be applicable to the Warrants (including, in the case of any such
consolidation, merger or sale in which the successor entity or purchasing entity
is other than the Company, an immediate adjustment of the Exercise Price to the
value for the Common Stock reflected by the terms of such consolidation, merger
or sale, and a corresponding immediate adjustment in the number of shares of
Common Stock acquirable and receivable upon exercise of the Warrants). The
Company shall not effect any such consolidation, merger or sale, unless prior to
the consummation thereof, the successor entity (if other than the Company)
resulting from consolidation or merger or the entity purchasing such assets
assumes by written instrument (in form and substance satisfactory to the
Registered Holders of Warrants representing a majority of the Common Stock
obtainable upon exercise of all of the Warrants then outstanding), the
obligation to deliver to each such holder such shares of stock, securities or
assets as, in accordance with the foregoing provisions, such holder may be
entitled to acquire.

                  2E. Certain Events. If any event occurs of the type
contemplated by the provisions of this Section 2 but not expressly provided for
by such provisions (including, without limitation, the granting of stock
appreciation rights, phantom stock rights or other rights with equity features),
then the Company's board of directors shall make an appropriate adjustment in
the Exercise Price and the number of shares of Common Stock obtainable upon
exercise of this Warrant so as to protect the rights of the holders of the
Warrants; provided that no such adjustment shall increase the Exercise Price or
decrease the number of shares of Common Stock obtainable as otherwise determined
pursuant to this Section 2.

                  2F. Notices.

                           (i) Immediately upon any adjustment of the Exercise
Price, the Company shall give written notice thereof to the Registered Holder,
setting forth in reasonable detail and certifying the calculation of such
adjustment.

                           (ii) The Company shall give written notice to the
Registered Holder at least 20 days prior to the date on which the Company closes
its books or takes a record (A) with respect to any dividend or distribution
upon the Common Stock, (B) with respect to any pro rata subscription offer to
holders of Common Stock or (C) for determining rights to vote with respect to
any Organic Change, dissolution or liquidation.

                           (iii) The Company shall also give written notice to
the Registered Holders at least 20 days prior to the date on which any Organic
Change, dissolution or liquidation shall take place.

                  Section 3. Liquidating Dividends. If at any time on or after
the date this Warrant becomes exercisable the Company declares or pays a
dividend upon the Common Stock payable


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otherwise than in cash out of earnings or earned surplus (determined in
accordance with generally accepted accounting principles, consistently applied)
except for a stock dividend payable in shares of Common Stock (a "Liquidating
Dividend"), then the Company shall pay to the Registered Holder of this Warrant
at the time of payment thereof the Liquidating Dividend which would have been
paid to such Registered Holder on the Common Stock had this Warrant been fully
exercised immediately prior to the date on which a record is taken for such
Liquidating Dividend, or, if no record is taken, the date as of which the record
holders of Common Stock entitled to such dividends are to be determined;
provided that if the Liquidating Dividends consist of voting securities, the
Company shall make available to the Registered Holder of this Warrant, at such
holder's request, Liquidating Dividends consisting of securities (except as
otherwise required by law) which are otherwise identical to the Liquidating
Dividends consisting of voting securities.

                  Section 4. Purchase Rights. If at any time on or after the
date this Warrant becomes exercisable the Company grants, issues or sells any
Options, Convertible Securities or rights to purchase stock, warrants,
securities or other property pro rata to the record holders of any class of
Common Stock (the "Purchase Rights"), then the Registered Holder of this Warrant
shall be entitled to acquire, upon the terms applicable to such Purchase Rights,
the aggregate Purchase Rights which such holder could have acquired if such
holder had held the number of shares of Common Stock acquirable upon complete
exercise of this Warrant immediately before the date on which a record is taken
for the grant, issuance or sale of such Purchase Rights, or, if no such record
is taken, the date as of which the record holders of Common Stock are to be
determined for the grant, issue or sale of such Purchase Rights; provided that
if the Purchase Rights involve voting securities, the Company shall make
available to the Registered Holder of this Warrant, at such holder's request,
Purchase Rights involving securities (except as otherwise required by law) which
are otherwise identical to the Purchase Rights involving voting securities.

                  Section 5. Definitions. The following terms have meanings set
forth below:

                  "Common Stock" means the Company's Common Stock, par value
$0001 per share and any capital stock of any class of the Company hereafter
authorized which is not limited to a fixed sum or percentage of par or stated
value in respect to the rights of the holders thereof to participate in
dividends or in the distribution of assets upon any liquidation, dissolution or
winding up of the Company.

                  "Common Stock Deemed Outstanding" means, at any given time,
the number of shares of Common Stock actually outstanding at such time, plus the
number of shares of Common Stock deemed to be outstanding pursuant to Sections
2B(i) and 2B(ii) hereof regardless of whether the Options or Convertible
Securities are actually exercisable at such time, but excluding any shares of
Common Stock issuable upon exercise of the Warrants.

                  "Convertible Securities" means any stock or securities
(directly or indirectly) convertible into or exchangeable for Common Stock.


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                  "Market Price" means as to any security the average of the
closing prices of such security's sales on all domestic securities exchanges on
which such security may at the time be listed, or, if there have been no sales
on any such exchange on any day, the average of the highest bid and lowest asked
prices on all such exchanges at the end of such day, or, if on any day such
security is not so listed, the average of the representative bid and asked
prices quoted in the NASDAQ System as of 4:00 P.M., New York time, on such day,
or, if on any day such security is not quoted in the NASDAQ System, the average
of the highest bid and lowest asked prices on such day in the domestic
over-the-counter market as reported by the National Quotation Bureau,
Incorporated, or any similar successor organization, in each such case averaged
over a period of 21 days consisting of the day as of which "Market Price" is
being determined and the 20 consecutive business days prior to such day;
provided that if such security is listed on any domestic securities exchange the
term "business days" as used in this sentence means business days on which such
exchange is open for trading. If at any time such security is not listed on any
domestic securities exchange or quoted in the NASDAQ System or the domestic
over-the-counter market, the "Market Price" shall be the fair value thereof
determined jointly by the Company and the Registered Holders of Warrants
representing a majority of the Common Stock purchasable upon exercise of all the
Warrants then outstanding; provided that if such parties are unable to reach
agreement within a reasonable period of time, such fair value shall be
determined by an appraiser jointly selected by the Company and the Registered
Holders of Warrants representing a majority of the Common Stock purchasable upon
exercise of all the Warrants then outstanding. The determination of such
appraiser shall be final and binding on the Company and the Registered Holders
of the Warrants, and the fees and expenses of such appraiser shall be paid by
the Company.

                  "Options" means any rights or options to subscribe for or
purchase Common Stock or Convertible Securities.

                  "Person" means an individual, a partnership, a joint venture,
a corporation, a limited liability company, a trust, an unincorporated
organization and a government or any department or agency thereof.

                  Other capitalized terms used in this Warrant but not defined
herein shall have the meanings set forth in the Loan Agreement.

                  Section 6. No Voting Rights; Limitations of Liability. This
Warrant shall not entitle the holder hereof to any voting rights or other rights
as a stockholder of the Company. No provision hereof, in the absence of
affirmative action by the Registered Holder to purchase Common Stock, and no
enumeration herein of the rights or privileges of the Registered Holder shall
give rise to any liability of such holder for the Exercise Price of Common Stock
acquirable by exercise hereof or as a stockholder of the Company.

                  Section 7. Warrant Transferable. Subject to the transfer
conditions referred to in the legend endorsed hereon, this Warrant and all
rights hereunder are transferable, in whole or in part, without charge to the
Registered Holder, upon surrender of this Warrant with a properly executed


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Assignment (in the form of Exhibit II hereto) at the principal office of the
Company, subject to compliance with applicable federal and state securities
laws.

                  Section 8. Warrant Exchangeable for Different Denominations.
This Warrant is exchangeable, upon the surrender hereof by the Registered Holder
at the principal office of the Company, for new Warrants of like tenor
representing in the aggregate the purchase rights hereunder, and each of such
new Warrants shall represent such portion of such rights as is designated by the
Registered Holder at the time of such surrender; provided that, as long as any
Subject Shares remain outstanding, this Warrant shall only be exchangeable in
connection with the exchange of the certificate representing such Subject Shares
pursuant to the Company's Certificate of Incorporation. The date the Company
initially issues this Warrant shall be deemed to be the "Date of Issuance"
hereof regardless of the number of times new certificates representing the
unexpired and unexercised rights formerly represented by this Warrant shall be
issued. All Warrants representing portions of the rights hereunder are referred
to herein as the "Warrants."

                  Section 9. Replacement. Upon receipt of evidence reasonably
satisfactory to the Company (an affidavit of the Registered Holder shall be
satisfactory) of the ownership and the loss, theft, destruction or mutilation of
any certificate evidencing this Warrant, and in the case of any such loss, theft
or destruction, upon receipt of indemnity reasonably satisfactory to the Company
(provided that if the holder is a financial institution or other institutional
investor its own agreement shall be satisfactory), or, in the case of any such
mutilation upon surrender of such certificate, the Company shall (at its
expense) execute and deliver in lieu of such certificate a new certificate of
like kind representing the same rights represented by such lost, stolen,
destroyed or mutilated certificate and dated the date of such lost, stolen,
destroyed or mutilated certificate.

                  Section 10. Notices. Except as otherwise expressly provided
herein, all notices referred to in this Warrant shall be in writing and shall be
delivered personally, sent by reputable overnight courier service (charges
prepaid) or sent by registered or certified mail, return receipt requested,
postage prepaid and shall be deemed to have been given when received (if hand
delivered) or five days after delivered, sent or deposited in the U.S. Mail or
by overnight courier (i) to the Company, at its principal executive offices and
(ii) to the Registered Holder of this Warrant, at such holder's address as it
appears in the records of the Company (unless otherwise indicated by any such
holder).

                  Section 11. Amendment and Waiver. Except as otherwise provided
herein, the provisions of the Warrants may be amended and the Company may take
any action herein prohibited, or omit to perform any act herein required to be
performed by it, only if the Company has obtained the written consent of the
Registered Holders of Warrants representing a majority of the shares of Common
Stock obtainable upon exercise of the Warrants; provided that no such action may
change the Exercise Price of the Warrants or the number of shares or class of
stock obtainable upon exercise of each Warrant without the written consent of
Marquette Venture Partners III, L.P.

                  Section 12. Descriptive Headings; Governing Law. The
descriptive headings of the several Sections and paragraphs of this Warrant are
inserted for convenience only and do not constitute a part of this Warrant. The
corporation laws of the State of Arizona shall govern all issues


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<PAGE>   12

concerning the relative rights of the Company and its stockholders. All other
questions concerning the construction, validity, enforcement and interpretation
of this Warrant shall be governed by the internal law of the State of Arizona,
without giving effect to any choice of law or conflict of law provision or rule
(whether of the State of Arizona or any other jurisdictions) that would cause
the application of the laws of any jurisdictions other than the State of
Arizona.


                                     * * * *


                                       12
<PAGE>   13

                  IN WITNESS WHEREOF, the Company has caused this Warrant to be
signed and attested by its duly authorized officers under its corporate seal and
to be dated the Date of Issuance hereof.


                                        ALLIANCE MEDICAL CORPORATION

                                        By  ________________________________

                                        Its ________________________________


[Corporate Seal]

Attest:


________________________
Secretary


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<PAGE>   14

                                                                       EXHIBIT I

                               EXERCISE AGREEMENT

To:                                                   Dated:

         The undersigned, pursuant to the provisions set forth in the attached
Warrant (Certificate No. W-___), hereby agrees to subscribe for the purchase of
_______ shares of the Common Stock covered by such Warrant and makes payment
herewith in full therefor at the price per share provided by such Warrant.


                                       Signature ______________________________

                                       Address ________________________________


                                                                      EXHIBIT II

                                   ASSIGNMENT

                  FOR VALUE RECEIVED, _______________________ hereby sells,
assigns and transfers all of the rights of the undersigned under the attached
Warrant (Certificate No. W-____) with respect to the number of shares of the
Common Stock covered thereby set forth below, unto:

Names of Assignee               Address                           No. of Shares

Dated:                              Signature ________________________________
                                              ________________________________

                                    Witness   ________________________________


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<PAGE>   15

                                                                     EXHIBIT III

                             CAPITALIZATION SCHEDULE

                                (Attached hereto)


                                       15
<PAGE>   16

                                                                      EXHIBIT IV


                                   TERM SHEET

                                (Attached hereto)


                                       16