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                                  EXHIBIT 4.4

                                AMENDMENT NO. 3
                                       TO
                               ADAC LABORATORIES'
                      DIRECTORS' STOCK OPTION PLAN (1987)


         The Directors' Stock Option Plan (1987) (the "Plan") of ADAC
Laboratories, a California Corporation (the "Company"), is hereby amended in
the following respects:

                 1.       DEFINITIONS.

                 Section 2(d), concerning the definition of "Directors'
Options," is hereby amended to delete the sentence and to substitute in its
place the following sentence:

                          "(d)    'Directors' Options' shall mean options to
         purchase shares of Company Common Stock which may be granted each
         fiscal year by the Company to each person serving as a director of the
         Company who is not also an employee of the Company or any of its
         Subsidiary corporations."

                 2.       SHARES SUBJECT TO THE PLAN.

                 Section 5 of the Plan, entitled "Shares Subject to the Plan,"
is hereby amended to delete the first sentence and to substitute in its place
the following first sentence:

                          "Subject to the provisions of Section 12 (relating to
         adjustments in the number of shares upon certain changes), the Shares
         which may be sold pursuant to Directors' Options granted under the
         Plan shall not exceed in the aggregate 231,666 shares of the Company's
         authorized Common Stock."

                 3.       OPTION GRANTS.

                 Section 6, entitled "Annual Option Grants," is deleted in its
entirety and the following is substituted in its place:

                          "6.  Annual Option Grants.

                                  The number of shares to be optioned to each
         non-employee director shall be fixed at 3,333 Option Shares during
         each fiscal year of the Company and such grant shall automatically
         occur on March 15th of each year  except during each fifth year the
         director shall receive a grant of 20,000 shares (in lieu of the 3,333
         share annual grant), provided, however, that on the date a person
         first becomes a director such person shall receive an option grant of
         20,000 shares.  Each option shall be for a term of five (5) years from
         the date of grant and each annual 3,333 share grant shall vest and
         become fully exercisable upon the first anniversary of
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ADAC Laboratories
Amendment No. 3 to Directors' Stock Option Plan (1987)


         the date of grant and each 20,000 share grant shall vest and become
         exercisable 25% per year.  An option agreement, signed by an officer
         of the Company, shall be issued to each person to whom an option is
         granted."

                          4.      "EXERCISE OF OPTIONS."

                 Section 10(a), entitled "Exercise of Options," is hereby
deleted in its entirety and the following subsection is substituted in its
place:

                          "(a)    Except in the event of death, in which case
         the Directors' Options may be exercised in full immediately, and
         except as provided in Section 12 below, Directors' Options may be
         exercised only as follows: (i) each annual 3,333 share grant shall
         vest and become fully exercisable upon the first anniversary of the
         date of grant and (ii) each 20,000 share grant shall vest and become
         fully exercisable 25% per year."

                 5.       "CHANGE IN CONTROL."

                 Section 12(b), entitled "Changes in Capitalization:  Splits,
Liquidations, Mergers and Reorganizations," is deleted in its entirety and the
following subsection is substituted in its place:

                          "(b)(i)  Except and to the extent provided otherwise
         in, or limited by, employment, severance or similar written agreements
         between the Company and an Optionee, ten (10) days prior to a "Change
         in Control" (as defined below), all stock options which are then not
         exercisable shall immediately vest and become exercisable, regardless
         of the original vesting schedule.  A "Change in Control" of the
         Company shall be deemed to have occurred if (a) any "person" or
         "group" (as defined in or pursuant to Sections 13(d) or 14(d) of the
         Securities Exchange Act of 1934, as amended (the "Exchange Act")),
         becomes the "beneficial owner" (as defined in Rule 13d-3 promulgated
         under the Exchange Act), directly or indirectly, of securities of the
         Company representing 40% or more of the voting power of the common
         stock outstanding which votes generally for the election of directors;
         (b) as a result of market or corporate transactions or shareholder
         action, the individuals who constitute the Board of Directors of the
         Company at the beginning of any period of 12 consecutive months (but
         commencing not earlier than July 1, 1995), plus any new directors
         whose election or nomination was approved by a vote of at least
         two-thirds of the directors still in office who were directors at the
         beginning of such period of 12 consecutive months, cease for any
         reason during





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ADAC Laboratories
Amendment No. 3 to Directors' Stock Option Plan (1987)


         such period of 12 consecutive months to constitute at least two-thirds
         of the members of such Board; or (c) the Company sells, through
         merger, assignment or otherwise, in one or more transactions other
         than in the ordinary course of business, assets which provided at
         least 2/3 of the revenues or pre-tax net income of the Company and its
         subsidiaries on a consolidated basis during the most
         recently-completed fiscal year.

                          (ii)  Notwithstanding paragraph (i) above, the
         following events shall not constitute a Change in Control:  any
         acquisition of beneficial ownership pursuant to (a) a
         reclassification, however effected, of the Company's authorized common
         stock, or (b) a corporate reorganization involving the Company or any
         of its subsidiaries which does not result in a material change in the
         ultimate ownership by the shareholders of the Company (through their
         ownership of the Company or its successor resulting from the
         reorganization) of the assets of the Company and its subsidiaries, but
         only if such reclassification or reorganization has been approved by
         the Company's Board of Directors."

                 6.       EFFECTIVE DATE.

                 In all other respects, and except as expressly provided
herein, the Plan is hereby confirmed.  These amendments to the Plan, as set
forth herein, have been approved by the Board of Directors on November 2, 1995,
and the amendments set forth in paragraphs 2, 3 and 5 above have been approved
by the shareholders on March 6, 1996 and all amendments are effective on and as
of such later date.
                                              BY ORDER OF THE BOARD OF DIRECTORS


                                              By /s/ David L. Lowe     
                                                 -------------------------------
                                                 David L. Lowe,
                                                    Chairman of the Board






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