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                                  EXHIBIT 4.3

                               ADAC LABORATORIES
               AMENDMENT TO DIRECTOR'S STOCK OPTION PLAN (1987),
                                   AS AMENDED



         The Director's Stock Option Plan 1987, as amended (the "Plan"), of
ADAC Laboratories, a California corporation (the "Company"), as previously
amended, is hereby further amended in the following respects:

         1.      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 upon changes in shares), the Shares which may be
                 sold pursuant to Directors' Options granted under the Plan
                 shall not exceed in the aggregate 500,000* shares of the
                 Company's Common Stock".

         2.      EFFECTIVE DATE.  In all other respects, and except as
expressly provided herein, the Plan is hereby confirmed.  This Amendment to the
Plan, as set forth herein, has been approved by the Board of Directors of the
Company on May 6, 1992 and is made subject to the consent of the shareholders
at the Company's next Annual Meeting of Shareholders.


                                              BY ORDER OF THE BOARD OF DIRECTORS



                                              By   /s/ Stanley D. Czerwinski 
                                                   -----------------------------

                                              Title  President                 
                                                    ----------------------------






*Prior to 1-for-3 reverse stock split.
