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                 FIRST AMENDMENT TO AGREEMENT AND PLAN OF MERGER

         This FIRST AMENDMENT TO AGREEMENT AND PLAN OF MERGER (this
"Amendment"), dated as of July 10, 2001, is entered into by and among INSIGHT
HEALTH SERVICES HOLDINGS CORP., a Delaware corporation ("PARENT"), JWCH MERGER
CORP., a Delaware corporation ("ACQUISITION"), and INSIGHT HEALTH SERVICES
CORP., a Delaware corporation (the "COMPANY"), amending that certain Agreement
and Plan of Merger, dated as of June 29, 2001, by and among Parent, Acquisition
and the Company (the "Agreement and Plan of Merger"). All capitalized terms used
herein and not defined in this Amendment shall have the meanings assigned to
them in the Agreement and Plan of Merger.

         WHEREAS, the parties previously entered into the Agreement and Plan of
Merger providing for the merger of Acquisition with and into the Company, with
the Company continuing as the surviving corporation;

         WHEREAS, the parties desire to amend Section 2.19 of the Agreement and
Plan of Merger; and

         WHEREAS, Section 13 of the Agreement and Plan of Merger permits the
amendment of the Agreement and Plan of Merger as provided in this Amendment.

         NOW, THEREFORE, in consideration of the foregoing and for good and
valuable consideration the receipt and adequacy of which is hereby acknowledged,
the parties agree as follows:

         1. VOTING REQUIREMENTS; BOARD APPROVAL AND RECOMMENDATION. Section
2.19(a) of the Agreement and Plan of Merger shall be amended and restated in its
entirety to read as follows:

         "(a) Assuming that the holders of Company Series B Preferred Stock and
Company Series C Preferred Stock convert all of their Company Series B Preferred
Stock and Company Series C Preferred Stock into Company Series D Preferred Stock
and/or Company Common Stock, the affirmative vote or consent, as of the
applicable record date, of the holders of a majority of all outstanding shares
of Company Common Stock and Company Preferred Stock, voting as a single class on
an as-converted basis (the "COMPANY STOCKHOLDER APPROVAL"), is the only vote of
the holders of any class or series of the Company's capital stock necessary to
adopt this Agreement and approve the Merger and the other transactions
contemplated hereby."

         2. COUNTERPARTS. This Amendment may be executed in counterparts, each
of which shall be deemed an original, and the Company, Acquisition and Parent
may become a party hereto by executing a counterpart hereof. This Amendment and
any counterpart so executed shall be deemed to be one and the same instrument.

         3. GOVERNING LAW. This Amendment shall be governed by and interpreted
and enforced in accordance with the laws of the State of Delaware, without
regard to the conflicts of law principles thereof.

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         4. RATIFICATION AND REAFFIRMATION OF THE AGREEMENT AND PLAN OF MERGER.
Except as hereby expressly amended, the Agreement and Plan of Merger shall
remain unchanged.

         5. INTERPRETATION. In the event of any conflict between the provisions
of this Amendment and the Agreement and Plan of Merger, the provisions of this
Amendment shall control.

         6. BINDING EFFECT. This Amendment shall inure to the benefit of and
shall be binding upon the parties and their respective successors and assigns.


                               [signatures follow]


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         IN WITNESS WHEREOF, the parties hereto, intending to be legally bound
hereby, have duly executed this Amendment as of the date first above written.



                               INSIGHT HEALTH SERVICES HOLDINGS CORP.



                               By: /s/ Edward D. Yun
                                  -------------------------------------------
                                  Name:  Edward D. Yun
                                  Title:  President

                               JWCH MERGER CORP.



                               By: /s/ Edward D. Yun
                                  -------------------------------------------
                                  Name:  Edward D. Yun
                                  Title:  President

                               INSIGHT HEALTH SERVICES CORP.



                               By: /s/ Steven T. Plochocki
                                  -------------------------------------------
                                  Name:  Steven T. Plochocki
                                  Title:  President and Chief Executive Officer


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