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                                 EXHIBIT 4.10


                     1997 Non-Qualified Stock Option Plan.

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                       DIAGNOSTIC HEALTH SERVICES, INC.
                       --------------------------------

                      1997 NONQUALIFIED STOCK OPTION PLAN
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     1.   Purposes.
          --------

          The purposes of the Diagnostic Health Services, Inc. 1997 Nonqualified
Stock Option Plan (this "Plan") are to aid Diagnostic Health Services, Inc. (the
"Company") and its subsidiaries in attracting and retaining capable management
and employees and to enable officers, directors, employees and/or consultants of
the Company and its subsidiaries to acquire or increase ownership interest in
the Company on a basis that will encourage them to perform at increasing levels
of effectiveness and use their best efforts to promote the growth and
profitability of the Company and its subsidiaries.  Consistent with these
objectives, this Plan authorizes the granting to officers, directors, employees
and/or consultants of options (collectively, "Options") to acquire shares of the
Company's common stock, $.001 par value per share ("Common Stock"), pursuant to
the terms and conditions hereinafter set forth.  As used herein, the term
"subsidiary" has the same meaning as is ascribed to the term "subsidiary
corporation" under Section 425 of the Internal Revenue Code of 1986, as amended
(the "Code").

          Options granted hereunder are not intended to be and shall not be
treated as "incentive stock options" within the meaning of Section 422 of the
Code.
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     2.   Effective Date.
          --------------

          This Plan shall become effective upon the adoption and approval hereof
by the Board of Directors of the Company (the "Board").

     3.   Administration.
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          (a) This Plan shall be administered by the Compensation Committee
of the Board, or, if no Compensation Committee shall then be constituted, a
committee consisting of three members of the Board who are selected by the Board
(in either case, the "Committee"); provided, however, that in the event that,
                                   --------  -------
and for so long as, the entire Board shall consist of only three members, then
the Board shall constitute the Committee hereunder. If, at any time, there are
less than three members of the Committee eligible to serve in such capacity, the
Board shall appoint one or more other eligible members of the Board to serve on
the Committee. All Committee members shall serve, and may be removed, at the
pleasure of the Board.

          (b) A majority of the members of the Committee (but not less than two)
shall constitute a quorum, and any action taken by a majority of such members
present at any meeting at which a quorum is present, or acts approved in writing
by all such members, shall be the acts of the Committee.

          (c) Subject to the other provisions of this Plan, the Committee shall
have full authority to decide the date or dates on which Options will be granted
under this Plan (in each instance, the "Date of Grant"), to select the officers,
directors, employees and/or consultants to whom Options will be granted, to
determine the number of shares of Common Stock to be covered by each Option, the
price at which such shares may be purchased upon the exercise of such Option
(the "Exercise Price") and other terms and conditions of such purchase.  In
making such determinations, the Committee shall solicit the recommendations of
the Chairman and President of the Company and may take into account each
proposed optionee's present and potential contributions to the Company's
business and any other factors which the Committee may deem relevant.  Subject
to the other provisions of this Plan, the Committee shall also have full
authority to (i) interpret this Plan and any stock option agreements evidencing
Options granted

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hereunder ("Option Agreements"), (ii) issue rules for administering this Plan,
(ii) change, alter, amend or rescind such rules, and (iv) make all other
determinations necessary or appropriate for the administration of this Plan. All
determinations, interpretations and constructions made by the Committee pursuant
to this Section 3 shall be final and conclusive. No member of the Board or the
Committee shall be liable for any action, determination or omission taken or
made in good faith with respect to this Plan or any Option granted hereunder.

     4.   Eligibility.
          -----------

          (a) All officers, directors, employees and/or consultants of the
Company (as determined by the Committee) shall be eligible to receive Options
under this Plan.

          (b) Anything elsewhere contained in this Plan to the contrary
notwithstanding, in no event and under no circumstances shall any Options be
granted under this Plan providing for an Exercise Price less than 100% of the
fair market value per share on the Date of Grant if the net pre-tax income of
the Company in the full fiscal year immediately preceding the Date of Grant of
such Option (the "Prior Year") did not exceed 125% of the mean average annual
net pre-tax income of the Company for the three fiscal years immediately
preceding the Prior Year; and in no event and under no circumstances (other than
by reason of any adjustment authorized herein to take place following the Date
of Grant) shall the Exercise Price under any Option on the Date of Grant of such
Option be less than 85% of the fair market value per share on such Date of
Grant.  For purposes hereof, the Company's net pre-tax income for any fiscal
year shall be the consolidated net pre-tax income of the Company and its
subsidiaries as reflected in the Company's consolidated audited financial
statements for such fiscal year, which shall be prepared in accordance with
generally accepted accounting principles applied on a consistent basis
throughout all periods in question.

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     5.   Option Shares.
          -------------

          (a) The shares subject to Options granted under this Plan shall be
shares of Common Stock and, except as otherwise required or permitted by Section
5(b) below, the aggregate number of shares with respect to which Incentive
Options may be granted hereunder shall not exceed 1,000,000 shares. If an Option
expires, terminates or is otherwise surrendered, in whole or in part, the shares
allocable to the unexercised portion of such Option shall again become available
for grants of Options hereunder. As determined from time to time by the Board,
the shares available under this Plan for grants of Options may consist either in
whole or in part of authorized but unissued shares of Common Stock or shares of
Common Stock which have been reacquired by the Company or a subsidiary following
original issuance.

          (b) The aggregate number of shares of Common Stock as to which
Options may be granted hereunder (as provided in Section 5(a) above), the number
of shares covered by each outstanding Option, and the Exercise Price applicable
to each outstanding Option shall be proportionately adjusted for any increase or
decrease in the number of issued shares of Common Stock resulting from a stock
split, recapitalization or other subdivision or consolidation of shares or other
adjustment, or the payment of a stock dividend in respect of the Common Stock;
provided, however, that any fractional shares resulting from any such adjustment
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shall be eliminated.

     6.   Terms and Conditions of Options.
          -------------------------------

          Each Option granted pursuant to this Plan shall be evidenced by an
Option Agreement between the Company and the officer, director, employee and/or
consultant to whom the Option is granted (the "Optionee") in such form or forms
as the Committee, from time to time, shall prescribe, which agreements may but
need not be identical to each other, but shall comply with and be subject to the
following terms and conditions:

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     (a) Exercise Price.  The Exercise Price at which each share of Common
         --------------
Stock may be purchased pursuant to an Option shall be determined by the
Committee in accordancw with the requirements of this Plan, but shall in no
event be less than 85% of the fair market value for each such share on the Date
of Grant of such Option, determined by the Committee as aforesaid; provided,
                                                                   --------
however, that the Option Agreement in respect of any or all Options may (but
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need not) provide that, in the event of any change in control and management of
the Company or any sale of the business of the Company, except to the extent
that the subject Optionee (or other person entitled to exercise such Option)
affirmatively elects, during a limited period of time after receiving notice of
such event, to permanently revoke and terminate the subject Option (in whole or
in part) and/or to reaffirm all or any portion of such Option without giving
effect to the reduction in Exercise Price hereinafter described, then the
otherwise applicable Exercise Price in respect of such Option may thereafter be
reduced (but not by more than 50%) in the event that, and at such time(s) as,
the subject Optionee (or other person entitled to exercise such Option)
thereafter exercises such Option (or the non-revoked and non-reaffirmed portion
thereof, as the case may be). Anything contained in this Section 6(a) to the
contrary notwithstanding, in the event that the number of shares of Common Stock
subject to any Option is adjusted pursuant to Section 5(b) above, a
corresponding adjustment shall be made in the Exercise Price per share.

          (b) Duration of Options.  The duration of each Option granted
              -------------------
hereunder shall be determined by the Committee, but shall in no event be later
than that date which is the day before the eighth anniversary of the Date of
Grant of such Option, subject to extension by mutual written agreement of the
Company and the subject Optionee (in each instance, the "Expiration Date").

          (c) Vesting of Options.  The vesting of each Option granted hereunder
              ------------------
shall be determined by the Committee, provided that, if no vesting requirements
are specified at the time of the granting of any Option hereunder, then the
subject Option shall be deemed to be fully vested and exercisable on the Date of
Grant.  Only the vested portion(s) of any Option may be exercised.

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          (d) Merger, Consolidation, etc.  In the event that the Company shall,
              ---------------------------
pursuant to action by the Board, at any time propose to merge into, consolidate
with, or sell or otherwise transfer all or substantially all of its assets to,
another corporation and provision is not made pursuant to the terms of such
transaction for (i) the assumption by the surviving, resulting or acquiring
corporation of all outstanding Options granted pursuant to this Plan, (ii) the
substitution of new options therefor, or (iii) the payment of cash or other
consideration in respect thereof, then the Committee shall cause written notice
of the proposed transaction to be given to each Optionee not less than thirty
(30) days prior to the anticipated effective date of the proposed transaction.
On a date which the Committee shall specify in such notice, which date shall be
not less than ten (10) days prior to the anticipated effective date of the
proposed transaction, each Optionee's Options shall become fully (100%) vested
and each Optionee shall have the right to exercise his or her Options to
purchase any or all shares then subject to such Options; and if the proposed
transaction is consummated, each Option, to the extent not previously exercised
prior to the effective date of the transaction, shall terminate on such
effective date.  If the proposed transaction is abandoned or otherwise not
consummated, then to the extent that any Option not exercised prior to such
abandonment shall have vested solely by operation of this Section 6(d), such
vesting shall be annulled and be of no further force or effect and the vesting
period otherwise established for or applicable to such Option pursuant to
Section 6(c) above shall be reinstituted as of the date of such abandonment;
provided, however, that nothing herein contained shall be deemed to
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retroactively affect or impair any exercise of any such vested Option prior to
the date of such abandonment.

          (e) Exercise of Options.  A person entitled to exercise an Option,
              -------------------
or any portion thereof, may exercise it (or such vested portion thereof) in
whole at any time, or in part from time to time, by delivering to the Company at
its principal office, directed to the attention of the President of the Company
or such other duly elected officer as shall be designated in writing by the
Committee to the Optionee, written notice specifying the number of shares of
Common Stock with respect to which the Option is being exercised, together with
payment in full of the aggregate Exercise Price for such shares. Such payment

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shall be made in cash or by certified check or bank draft to the order of the
Company; provided, however, that the Committee may, in its sole discretion,
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authorize such payment, in whole or in part, in any other form, including
payment by personal check or by the exchange of shares of Common Stock owned of
record by the person entitled to exercise the Option and having a fair market
value on the date of exercise equal to the price for which the shares of Common
Stock may be purchased pursuant to the Option.

          (f) Non-Transferability.  Any Option granted hereunder may, if so
              -------------------
provided in the subject Option Agreement, be transferable to members of the
Optionee's immediate family or by will or by the laws of decent and
distribution, and may, if so provided in the subject Option Agreement, be
pledged as collateral security in favor of another permitted holder of an Option
hereunder, solely as collateral for a loan made by such other holder to the
person making such pledge.

          (g) Termination of Employment; Competition.  The following provisions
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shall apply in the event of an Optionee's engaging in competition with the
Company, or in the event of the termination of an Optionee's employment with the
Company or any of its subsidiaries:

               (i) In the event that an Optionee shall engage or participate in,
     or become involved with, in any manner or capacity (whether as employee,
     agent, consultant, advisor, officer, director, manager, partner, joint
     venturer, investor, shareholder (other than passive investments in less
     than 5% of the outstanding securities of any company) or otherwise), any
     business enterprise which is engaged in the rendering of diagnostic
     ultrasound services, nuclear imaging, cardiac lab management, paramedical
     personnel placement, or any other business conducted or operated by the
     Company on the date on which such Optionee first became involved with such
     other business enterprise, or in the event that an Optionee's employment
     with the Company or any of its subsidiaries shall be terminated either (A)
     by the Company or any of its subsidiaries for "Cause" (as defined in any
     applicable employment agreement to which such Optionee is a party), or (in
     the absence of a definition contained in any applicable employment
     agreement) for fraud, dishonesty,

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     habitual drunkenness or drug use, for willful disregard of assigned duties
     or instructions by such Optionee, or for concrete actions causing
     substantial harm to the Company, or for other material breach by the
     Optionee of any applicable employment agreement to which the Optionee is a
     party, or (B) by the Optionee voluntarily and without the written consent
     of the Company, then all outstanding Options granted hereunder to such
                     ----
     Optionee shall automatically and immediately terminate at the time that
     notice of termination of employment is given, and shall not then or
     thereafter be exercisable in whole or in part; provided, however, that
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     nothing herein contained shall be deemed to modify or amend the terms and
     conditions of any applicable employment agreement, including but not
     limited to the grounds upon which any Optionee's employment may be
     terminated.

               (ii) In the event that an Optionee's employment with the Company
     or any of its subsidiaries shall terminate (A) by reason of retirement, or
     (B) under circumstances other than those specified in Section 6(g)(i) above
     and for other than death or disability, then all outstanding Options
                                             ----
     granted hereunder to such Optionee shall terminate three (3) months after
     the date of such termination of employment or on the Expiration Date,
     whichever shall first occur; provided, however, that if such Optionee
                                  --------  -------
     dies within such three (3) month period, then all outstanding Options
     granted hereunder to such Optionee shall terminate on the first anniversary
     of such Optionee's death or on the Expiration Date, whichever shall first
     occur.

               (iii) In the event of the death or disability of an Optionee
     while such Optionee is employed by the Company or any of its subsidiaries,
     all outstanding Options granted hereunder to such Optionee shall terminate
     on the first anniversary of such death or disability, as the case may be,
     or on the Expiration Date, whichever shall first occur.

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               (iv) Anything contained in this Section 6 to the contrary
     notwithstanding, an Option granted pursuant to this Plan may only be
     exercised following the subject Optionee's termination of employment with
     the Company or any of its subsidiaries for reasons other than death,
     disability or retirement if, and to the extent that, such Option was
     exercisable immediately prior to such termination of employment.

               (v) An Optionee's transfer of employment between the Company and
     any of its subsidiaries or between subsidiaries shall not constitute a
     termination of employment, and the Committee shall determine in each case
     whether an authorized leave of absence for professional education, military
     service or otherwise shall constitute a termination of employment.

               (vi) Nothing contained in this Section 6(g) shall be deemed to
     modify or affect any vesting schedule provided in any Option Agreement,
     which vesting schedule shall continue in effect and be applied and enforced
     notwithstanding any modification of the exercise period arising by reason
     of the application of this Section 6(g).

          (h) No Rights as a Stockholder or to Continued Employment.  No
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Optionee shall have any rights as a stockholder of the Company with respect to
any shares covered by an Option prior to the date of issuance to such Optionee
of the certificate or certificates for such shares. Neither this Plan nor any
Option granted hereunder shall confer upon an Optionee any right to continued
employment by the Company or any of its subsidiaries or interfere in any way
with the right of the Company or its subsidiaries to terminate the employment of
such Optionee (subject to the terms and conditions of any applicable employment
agreement between the Company or any of its subsidiaries and the subject
Optionee).

          (i) Designation.  Each Option Agreement entered into pursuant to this
              -----------
Plan shall specify therein that the subject Option has been granted under this
Plan.

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          (j) Other Terms and Conditions.  Any Option Agreement entered into
              --------------------------
pursuant to this Plan may contain such further terms and conditions (including a
right of first refusal in favor of the Company in the event that the Optionee
shall seek to transfer any shares acquired upon exercise of the subject Option)
as the Committee may determine, provided that such other terms and conditions
are not in violation of, in conflict with or otherwise inconsistent with the
requirements of this Plan.

     7.   Issuance of Shares; Restrictions.
          --------------------------------

          (a) Subject to the conditions, restrictions and other qualifications
provided in this Section 7, the Company shall, within thirty (30) business days
after an Option has been duly exercised in whole or in part, deliver to the
person who exercised the Option one or more certificates, registered in the name
of such person, for the number of shares of Common Stock with respect to which
the Option has been exercised.  The Company may legend any stock certificate
issued hereunder to reflect any restrictions provided for in this Section 7,
including but not limited to a "stop transfer" legend pursuant to Section 7(b)
below.

          (b) Unless the shares subject to Options granted under the Plan have
been registered under the Securities Act of 1933, as amended (the "Act") (and,
if the person exercising the Option may be deemed an "affiliate" of the Company
as such term is defined in Rule 405 under the Act, such shares have been
registered under the Act for resale by such person), or the Company has
determined that an exemption from registration under the Act is available, the
Company may require, prior to and as a condition of the issuance of any shares
of Common Stock upon exercise of any Option, that the person exercising such
Option hereunder furnish the Company with a written representation in a form
prescribed by the Committee to the effect that such person is acquiring such
shares solely with a view to investment for his or her own account and not with
a view to the resale or distribution of all or any part thereof, and that such
person will not dispose of any of such shares otherwise than in accordance with
the provisions of Rule 144 under the Act unless and until either the sale or
distribution of such shares is registered under the Act or the Company is
satisfied that an exemption from such registration is available.

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          (c) Anything herein contained to the contrary notwithstanding, the
Company shall not be obligated to sell or issue any shares of Common Stock
pursuant to the exercise of an Option granted hereunder unless and until the
Company is satisfied that such sale or issuance complies with all applicable
provisions of the Act and all other laws and/or regulations by which the Company
is bound or to which the Company or such shares may be subject; and the Company
reserves the right to delay the issuance and/or delivery of shares of Common
Stock for such period of time as may be required in order to effect compliance
with the applicable provisions of the Act and all other applicable laws and/or
regulations as aforesaid.

     8.   Substitute Options.
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          Anything herein contained to the contrary notwithstanding, Options
may, at the discretion of the Board, be granted under this Plan in substitution
for options to purchase shares of capital stock of another corporation which is
merged into, consolidated with or all or a substantial portion of the property
or stock of which is acquired by, the Company or a subsidiary.  The terms,
provisions and benefits to each Optionee under such substitute Options shall in
all respects be identical to the terms, provisions and benefits to such Optionee
of his or her options of the other corporation on the date of substitution,
except that such substitute Options shall provide for the purchase of shares of
Common Stock of the Company instead of shares of such other corporation.

     9.   Term of this Plan.
          -----------------

          Unless this Plan has been sooner terminated pursuant to Section 10
below, this Plan shall terminate on, and no Options hereunder shall be granted
after, the tenth (10th) anniversary of the date of the adoption and approval of
this Plan by the Board.  Notwithstanding any such Plan termination, the
provisions of this Plan shall nonetheless continue thereafter to govern all
Options theretofore granted (including but not limited to any Options the
Expiration Date of which is extended to any date subsequent to the termination
of this Plan) until the exercise, expiration or cancellation of such Options.

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     10.  Amendment and Termination of Plan.
          ---------------------------------

          The Board may at any time terminate this Plan, or amend this Plan from
time to time in such respects as the Board deems desirable; provided, however,
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that, subject to the provisions of Sections 6 and 7 above, no termination hereof
or amendment hereto shall adversely affect the rights of an Optionee or other
person holding an Option theretofore granted hereunder without the consent of
such Optionee or other person, as the case may be.

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