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                                                                   Exhibit 10.53

                                 AMENDMENT NO. 2
                                       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. 2 ("Amendment") to the Loan and Security Agreement is made
and entered into as of March 31, 1999, 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.       Borrower and Lender desire to amend the terms of the
                  Agreement.

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. The following new Section 2.12 is incorporated into the Agreement:

              "2.12 Overadvance 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 an "Overadvance
       Loan"), up to an aggregate unpaid principal amount not to exceed at any
       time Three Million Dollars ($3,000,000), on and subject to the following
       terms and conditions (the "Overadvance Facility"):

              (a) An Overadvance Loan may be made to satisfy Borrower's working
       capital needs to the extent they exceed the formula-determined Borrowing
       Base;

              (b) Each Overadvance Loan shall be due and payable in accordance
       with the terms of this Agreement and shall constitute Obligations secured
       by the Collateral;

              (c) No Guaranty shall be in default and each shall be in full
       force and effect at the time any Overadvance Loan is made;

              (d) Borrower will pay Lender interest on the principal amount of
       any Overadvance Loan outstanding at the rates provided for Loans herein;
       and

              (e) Except as provided to the contrary in clauses (a) through (d)
       above, Overadvance Loans pursuant to this Section 2.12 shall be subject
       to all other terms and conditions of this Agreement.

        Notwithstanding anything else herein, the total outstanding principal
       amount of all Loans under this Agreement shall not at any time exceed
       $35,000,000."


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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" shall mean the lesser of (a) the Commitment Amount
         or (b) the sum of (i) the Borrowing Base plus (ii) the $3,000,000
         maximum amount of the Overadvance Facility, minus the aggregate
         Advances and other monetary Obligations outstanding under this
         Agreement."

3.       The Term set forth in Section 2.7 of the Agreement shall be extended to
February 28, 2001.

4.       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.

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

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

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.


BORROWER:                                       LENDER:

U.S. DIAGNOSTIC INC.                            DVI BUSINESS CREDIT CORPORATION

By: /s/ Joseph A. Paul                          By: /s/ Mark H. Idzerda
   ------------------------------------            -----------------------------

Print Name: Joseph A. Paul                      Print Name: Mark H. Idzerda
          -----------------------------                    ---------------------
Title:  President                               Title: President
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