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                                                                     Exhibit 3.5

                            CERTIFICATE OF AMENDMENT
                                     OF THE
                      RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                                RADIOLOGIX, INC.

                         PURSUANT TO SECTION 242 OF THE
                GENERAL CORPORATION LAW OF THE STATE OF DELAWARE


         Radiologix, Inc., a corporation organized and existing under and by
virtue of the General Corporation Law of the State of Delaware (the
"Corporation"),

DOES HEREBY CERTIFY:

         FIRST: That, upon the direction of the Corporation's Board of
Directors, the following proposed amendment ("Amendment") of the Restated
Certificate of Incorporation of the Corporation was submitted to the
stockholders of the Corporation for consideration at the Annual Meeting of the
Stockholders of the Corporation held on June 10, 2003:

         Article VII of the Corporation's Amended and Restated Certificate of
         Incorporation is proposed to be amended by deleting the phrase "the
         second or third sentences of the first paragraph of Article III,
         Section 2 of the Bylaws regarding the composition of the Board, or any
         other" so that, as amended, Article VII of the Corporation's Amended
         and Restated Certificate of Incorporation states in its entirety as
         follows:

                           The management of the business and conduct of the
                  affairs of the Corporation shall be vested in its Board. The
                  number of directors which shall constitute the whole Board
                  shall be fixed by, or in the manner provided in, the Bylaws of
                  the Corporation. In furtherance and not in limitation of the
                  Board's power to manage the business and conduct the affairs
                  of the Corporation, the Board shall have the power, upon the
                  affirmative vote of at least a majority of the Directors then
                  serving, to adopt, amend or repeal from time to time the
                  Bylaws of the Corporation, subject to the right of the
                  stockholders entitled to vote thereon to adopt, amend or
                  repeal the Bylaws. Notwithstanding the foregoing, the Board
                  shall not have the power to alter, amend or repeal any Bylaw
                  (or Article or Section thereof) that expressly provides that
                  it cannot be altered, amended or repealed by the Board.

         SECOND: The number of shares required by statute were voted in favor of
the Amendment at the Annual Meeting of Stockholders of the Corporation held on
June 10, 2003.

         THIRD: The Amendment was duly adopted in accordance with the provisions
of Section 242 of the General Corporation Law of the State of Delaware.

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         IN WITNESS WHEREOF, the Corporation has caused this certificate to be
signed by its duly authorized officer this 14th day of July, 2003.

                               RADIOLOGIX, INC.

                               By: Sami S. Abbasi
                                  ----------------------------------------------
                                   Sami S. Abbasi, Executive Vice President

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