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                                                                   Exhibit 10.68



                                AMENDMENT NO. 6
                                      TO
                          LOAN AND SECURITY AGREEMENT
                     DATED FEBRUARY 25, 1997 ("AGREEMENT")
                                    BETWEEN
                       U.S. DIAGNOSTIC INC. ("BORROWER")
                                      AND
                  DVI BUSINESS CREDIT CORPORATION ("LENDER")


         This Amendment No. 6 ("Amendment") to the Loan and Security Agreement
is made and entered into as of January 18, 2000, by and between U.S. Diagnostic
Inc. ("Borrower") and DVI Business Credit Corporation ("Lender").

                                   RECITALS

         A.  Borrower and Lender entered into a Loan and Security Agreement
             dated February 25, 1997, and all amendments thereto (collectively
             referred to as the "Agreement") pursuant to which Borrower
             obtained a revolving loan in the amount of Thirty Five Million
             Dollars ($35,000,000).

         B.  The parties now desire to amend certain terms of the Agreement on
             and subject to the terms hereof.

         NOW, THEREFORE, in consideration of the mutual covenants and
agreements set forth herein, and for other good and valuable consideration, the
receipt and sufficiency of which are being acknowledged and affirmed, the
parties hereto agree as follows:

         1.  A new Section 2.13 is hereby inserted in the Agreement:

                  "2.13 Loan B Additional Facility. Subject to the terms of
         this Agreement, Lender agrees, for so long as no Event of Default
         exists, to provide Borrower, and Borrower agrees to accept,
         overadvance financing for the purposes described herein (each advance
         being a "Loan B Additional Advance"), up to an aggregate unpaid
         principal amount not to exceed at any time Two Million Dollars
         ($2,000,000), subject to the provisions of item (e) below, and
         otherwise on and subject to the following terms and conditions (the
         "Loan B Additional Facility"):

                  (a) A Loan B Additional Advance may be made to satisfy
         Borrower's working capital needs to the extent they exceed the
         formula-determined Borrowing Base B.

                  (b) Each Loan B Additional Advance shall be due and payable in
         accordance with the terms of this Agreement and shall constitute
         Obligations.

                  (c) No Guaranty shall be in default and each shall be in full
         force and effect at the time any Loan B Additional Advance is made.

                  (d) Borrower will pay Lender interest on the principal amount
         of any Loan B Additional Advance outstanding at the rates provided for
         Loans herein.

                  (e) The Loan B Additional Facility, shall be repaid in whole
         on or before May 20, 2000, and to achieve such limitation, the Loan B
         Additional Facility shall be reduced by $180,000 per week


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         commencing on March 1, 2000. If the foregoing provisions for repayment,
         or any of them, are not satisfied by Borrower, it shall constitute an
         Event of Default. To the extent that the Loan B Additional Facility is
         not repaid by the final maturity date described above, all cash
         receipts and other monies received on Loan B will immediately serve to
         repay the Loan B Additional Facility.

                  (f) Except as provided to the contrary in the provisions
         above, the Loan B Additional Facility pursuant to this Section 2.13
         shall be subject to all other terms and conditions of this Agreement.
         In no event shall any amount of the Loan B Additional Facility be
         available under Loan A.

         Notwithstanding anything else herein, the total outstanding principal
         amount of all Loans under Loan B shall at no time exceed $11,000,000.

         2.  The definition of "Loan Availability" in Section 1.1 of the
Agreement is deleted in its entirety and replaced with the following:

         "'Loan Availability A' shall mean the lesser of (a) the Commitment
         Amount A or (b) the sum of (i) the Borrowing Base A, plus (ii) the then
         existing maximum amount of the Overadvance Facility, minus the
         aggregate Advances under Loan A and other monetary Obligations
         outstanding under this Agreement allocable to Loan A.

         "'Loan Availability B' shall mean the lesser of (a) the Commitment
         Amount B or (b) the sum of (i) the Borrowing Base B, plus (ii) the then
         existing maximum amount of the Loan B Additional Facility, minus the
         aggregate Advances under Loan B and other monetary Obligations
         outstanding under this Agreement allocable to Loan B."

         For purposes of the Agreement any reference to the term Loan
         Availability in the Loan Documents shall be interpreted with the
         foregoing amendment, as the context so requires.

         3.  The Agreement shall be amended to provide that on or before the
first day of each month following the date hereof, Borrower shall pay Lender a
monthly maintenance fee of Eight Thousand Five Hundred Dollars ($8,500).
Increases to the Loan Availability during the term will be charged an
incremental increase in the monthly maintenance fee proportionate to the
percentage increase in the Loan Availability.

         4.  The term "Borrowing Base" in Section 1 of the Agreement, is hereby
amended by deleting the reference therein to "eighty percent (80%)" and
replacing it with "eighty-five percent (85%)".

         5.  Wilkes Barre Imaging is hereby added as a Loan B Guarantor under
the Agreement.

         6.  Except as expressly amended by this Amendment, the Agreement
remains in full force and effect. References to the Agreement are deemed to mean
the Agreement as amended by this Amendment.

         7.  This Amendment may be executed in counterparts, all of which when
taken together constitute one and the same instrument.

         8.  This Amendment is governed by and must be interpreted and construed
in accordance with the laws of the State of California.

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Lender is entering into this Amendment without any forbearance, and without
waiver or prejudice of defaults, events of default, and any rights or remedies
Lender has or may have under the Agreement and applicable law. Lender hereby
expressly reserves the right to declare a default in accordance with the
Agreement and exercise all of Lender's rights and remedies thereunder.

All capitalized terms used herein and not otherwise defined herein shall have
the same meaning as in the Agreement. Any provision in the Amendment hereof
that may be contrary to any provision of the Agreement shall prevail and
override the Agreement. Except as expressly set forth herein, all other
provisions of the Agreement shall remain in full force and effect. Borrower and
Lender warrant to each other that this Amendment has been authorized and duly
executed and is binding on all parties hereto as of the date first above
written.


BORROWER                                     LENDER

U.S. DIAGNOSTIC INC.                         DVI BUSINESS CREDIT CORPORATION


By:                                          By:
   ----------------------------                 ----------------------------

Name: Paul Andrew Shaw                       Name: Cynthia J. Cohen
     --------------------------                   --------------------------

Title: Executive Vice President              Title: Executive Vice President
      -------------------------                    -------------------------


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