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                                                                   EXHIBIT 10.18

                                                          Amendment to Documents

                   AMENDMENT NO. 1 TO BUSINESS LOAN AGREEMENT

     This Amendment No. 1 (the "Amendment") dated as of September 28, 2001, is
between Bank of America, N.A. (the "Bank") and U.S, Laboratories Inc. (the
"Borrower").

                                    RECITALS
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     A.  The Bank and the Borrower entered into a certain Business Loan
Agreement dated as of March 29, 2001 (the "Agreement").

     B.  The Bank and the Borrower desire to amend the Agreement.

                                    AGREEMENT
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     1.  Definitions. Capitalized terms used but not defined in this Amendment
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shall have the meaning given to them in the Agreement.

     2.  Amendments.  The Agreement is hereby amended as follows:
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          2.1      In Paragraph 2.2 of the Agreement, the date "May 31, 2003" is
                   substituted for the date "May 31, 2002".

          2.2      Paragraph 8.5 of the Agreement is deleted in its entirety.

          2.3      Paragraph 9.11 of the Agreement is amended to read in its
                   entirety as follows:

                   "9.11 Tax Matters.  The Borrower has no knowledge of any
                   pending assessments or adjustments of its income tax for any
                   year and all taxes due have been paid."

     3.  Representations; and Warranties. When the Borrower signs this
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Amendment, the Borrower represents and warrants to the Bank that: (a) there is
no event which is, or with notice or lapse of time or both would be, a default
under the Agreement except those events, if any, that have been disclosed in
writing to the Bank or waived in writing by the Bank, (b) the representations
and warranties in the Agreement are true as of the date of this Amendment as if
made on the date of this Amendment, (e) this Amendment is within the Borrower's
powers, has been duly authorized, and does not conflict with any of the
Borrower's organizational papers, and (d) this Amendment does not conflict with
any law, agreement, or obligation by which the Borrower is bound.

     4.  Conditions. This Amendment will be effective when the Bank receives the
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following items, in form and content acceptable to the Bank.

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         4.1  Certificate of good standing for the Borrower from its state of
              formation.

     5.  Effect of Amendment. Except as provided in this Amendment, all of the
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terms and conditions of the Agreement shall remain in full force and effect.

This Amendment is executed as of the date stated at the beginning of this
Amendment.

BANK OF AMERICA, N.A.                       U.S. LABORATORIES, INC.



X    /s/                                    X     /s/ Dickerson Wright
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By:                                         By:  Dickerson Wright, Chairman/
                                                 Chief Executive Officer

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