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                                                                   EXHIBIT 10.13
STATE OF GEORGIA  )
                  )
FULTON COUNTY     )


                               RETAINER AGREEMENT

      THIS RETAINER AGREEMENT ("Agreement") is made and entered into as of
the 1st day of July, 2001, by and between WILLIAM T. CARLSON, Jr.
("Carlson"), and MQ ASSOCIATES, INC., a Delaware corporation, with its
principal offices in Alpharetta, Georgia ("Company").

                                    RECITALS

1.    Carlson is a licensed attorney, specializing in the field of health
      care law.

2.    Company is a corporation engaged in the business of owning and
      operating diagnostic imaging centers throughout the United States.

3.    The parties desire to enter into this Agreement in order that Carlson
      might provide certain legal and consulting services to Company in
      furtherance of Company's business objectives and to better ensure the
      success of the business.

NOW, THEREFORE, premises considered, the parties agree as follows:

                                    AGREEMENT

1.    ENGAGEMENT.  Company hereby retains Carlson, as its attorney and
      general legal counsel, and Carlson hereby agrees to represent Company
      as its attorney.

2.    LEGAL SERVICES TO BE PERFORMED. Carlson will perform legal services as
      general counsel for the Company. Carlson will be present and available to
      perform such services at Company's offices in Alpharetta, Georgia an
      average of four days per week. In addition, Carlson shall devote such time
      as is reasonably necessary to deal with the Company's legal affairs when
      he is not present at the Company's offices.

3.    FEES.  For the professional services rendered by Carlson, Company
      agrees to pay to Carlson the sum of Thirty Thousand Dollars ($30,000.00)
      per month, payable on the last day of each calendar month for services
      rendered during the preceding month.

4.    EXPENSES.  In addition to fees paid to Carlson, as provided, Company
      also agrees to reimburse all expenses properly incurred by Carlson in
      the course of this representation.  Expenses will include, but are not
      limited to, items such as filing fees, travel, lodging, meals,
      telephone calls, photocopying, facsimiles and courier services.  Major
      out-of-pocket


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      expenses (cost of consultants, experts, or outside counsel engaged on
      behalf of Company) may, in the alternative, be billed directly and
      forwarded to Company for payment.

5.    EXTRAORDINARY SERVICES.  From time to time during the term of this
      Agreement, Company intends to engage Carlson to perform extraordinary
      services, such as representing the Company in acquisitions and other
      transactions.  In the event that Company engages Carlson to perform
      such services, it shall pay Carlson an additional fee equal to one
      percent (1%) of the transaction's value if said transaction is
      $5,000,000 or less, three-quarters percent (3/4%) of the transaction's
      value if said transaction is $5,000,001-10,000,000, and one-half
      percent (1/2%) of the transaction's value if said transaction is
      greater than $10,000,000.

6.    TERM AND TERMINATION.

      A.    TERM.  The term of this Agreement shall always be two years and
            renew daily.

      B.    TERMINATION.  Company shall have the right to terminate this
            Agreement and Carlson's legal representation of the Company upon
            90 days' prior written notice unless there is a Change of
            Control.  Company shall be obligated to pay for all services and
            expenses rendered or incurred prior to the effective date of
            termination.  For purposes of this Agreement, the effective date
            of termination shall be the day following conclusion of the
            90-day notice period.

7.    CHANGE OF CONTROL.

      A.    RIGHT TO SEVERANCE BENEFITS.  Carlson shall be entitled to
            receive severance benefits from Company, as described below,
            if there is a Change in Control of Company during the term of
            this Agreement and Company's successor wishes to terminate this
            Agreement.

      B.    DESCRIPTION OF SEVERANCE BENEFITS.  In the event that Carlson
            becomes entitled to receive severance benefits as provided
            herein, Carlson shall be retained as Attorney of Record to
            Company for 12 months in anticipation of transitioning to other
            legal counsel ("Transition Period") and Carlson shall be entitled
            to his regular monthly retainer payment ($30,000) for each of the
            12 months during the Transition Period and the payment of any
            costs and expenses incurred by Carlson during the Transition
            Period.  Within 30 days of the conclusion of the Transition
            Period, Company shall pay to Carlson a lump sum payment equal to
            the product of Carlson's monthly retainer fee times 12 months
            ($360,000).

      C.    CHANGE IN CONTROL.  A "Change in Control" shall be deemed to have
            occurred as of the first day that any one or more of the
            following have occurred:

            i.    any person other than those persons in control of Company
                  as of the effective date of this Agreement shall become the
                  beneficial owner,


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                  directly or indirectly, of securities of Company representing
                  50 percent or more of the combined voting power of Company's
                  then outstanding securities; or

            ii.   the persons constituting the Board of Directors of Company on
                  the effective date of this Agreement shall cease for any
                  reason to constitute at least 50 percent of the Board of
                  Directors of the Company; or

            iii.  the stockholders of Company shall approve a plan of complete
                  liquidation or an agreement for the sale or disposition of all
                  or substantially all of Company's assets, or a merger,
                  consolidation or reorganization of Company with or involving
                  any other entity, other than one that would result in the
                  voting securities of Company outstanding immediately prior
                  thereto continuing to represent 50.1 percent of the combined
                  voting power of the securities of Company or the surviving
                  entity.

8. MISCELLANEOUS.

      A.    HIPAA COMPLIANCE. To the extent required by and upon the compliance
            date of the Privacy Regulations promulgated by the United States
            Department of Health and Human Services and contained in 45 C.F.R.
            Parts 160 and 164 pursuant to the Health Insurance Portability and
            Accountability Act of 1996, 42 U.S.C. Sections 1320d-1329d-8 (the
            "Regulations"), the Parties shall enter into a mutually acceptable
            Business Associate (as that term is defined in the Regulations)
            Agreement whereby Carlson shall agree to only use and/or disclose
            protected health information in accordance with Business Associate
            provisions of the Regulations.

      B.    ACCESS TO BOOKS AND RECORDS. Upon written request of the Secretary
            of Health and Human Services or the Comptroller General or any of
            their duly authorized representatives, upon either party, the other
            party will make available those contracts, books, documents, and
            records necessary to verify the nature and extent of the costs of
            providing services under this Agreement. Such inspection shall be
            available up to four years after the rendering of such services. If
            either party carries out any of the duties of this Agreement through
            a subcontract with value of $10,000 or more over a 12-month period
            with a related individual or organization, that party agrees to
            include this requirement in any such subcontract. This section is
            included pursuant to and is governed by the requirements of Public
            Law 96-499, Sec. 952 [Sec. 1861(v)(1) of the Social Security Act]
            and the regulations promulgated thereunder. No attorney-client or
            other legal privilege will be deemed to have been waived by Company
            or by Carlson by virtue of this provision.


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      C.    AMENDMENT. This Agreement may be amended or modified by an
            instrument in writing executed by all parties.

      D.    BENEFITS. This agreement shall inure to the benefit of and be
            binding upon the parties, their heirs, legal representatives,
            successors and assigns.

      E.    ATTORNEYS' FEES. In the event of any litigation arising out of this
            Agreement, the court may award to the prevailing party all
            reasonable costs and expenses, including reasonable attorneys' fees.

      F.    GOVERNING LAW. The laws of the State of Georgia shall govern this
            Agreement, the construction of its terms and the interpretation of
            the rights and duties of the parties.

      IN WITNESS WHEREOF, the parties have executed this Agreement as of the day
and year first above written.


                                    WILLIAM T. CARLSON, JR.

                                    /s/ William T. Carlson, Jr.
                                    --------------------------------

                                    MQ ASSOCIATES, INC.


                                    By:  /s/ Illegible
                                         ---------------------------
                                    Its: President
                                         ---------------------------


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