March 1, 2000



Mr. Jerry Roda
Trex Medical Corporation
37 Apple Ridge Road
Danbury, CT 06810

Dear Jerry:

As we have discussed, Thermo Electron Corporation has announced a reorganization
of the company in which certain of the company's assets, including those of Trex
Medical, will be sold. We recognize that your past contributions have been
integral to the success of the company and that your continued involvement will
be necessary in order to facilitate the sale of Trex Medical Corporation and to
assure a smooth transition for a potential buyer.

RETENTION BONUS

In order to provide an incentive for you to remain with the company through the
completion of the sale, we will pay you a retention bonus of 80% of annual base
salary upon the sale or disposition of the business.

This retention bonus will be paid to you in one lump sum on or before ninety
(90) days following the closing date or March 31, 2001 whichever occurs first.

SEVERANCE

In addition to the retention bonus, we agree to pay you a severance in
recognition of your efforts as follows;

If not employed by new owner, you will be paid $155,000 in severance pay and a
bonus of $40,000 in a lump sum at the time your employment is terminated. In
addition, the company will pay the cost of family COBRA medical and dental
coverage for a period of 12 months after your employment termination.

TERMS OF AGREEMENT

         1. Trex Medical agrees to continue to employ you on the same terms and
            with the same benefits you currently enjoy as an employee-at-will.
            In return, you agree to remain in such employ and to continue to
            devote your full time and best efforts to Trex Medical as an
            employee-at-will until the closing date of the sale of Trex Medical.

         2. You understand that Trex Medical retains the right to terminate your
            services without cause (as defined below) and you retain the right
            to terminate your services for Trex Medical at any time. If your
            employment is terminated by the company for its convenience and
            without cause prior to the closing of sale, you will be paid your
            full and unreduced retention bonus and severance pay at the time of
            the sale. If you terminate your employment prior to the closing
            date, or Trex Medical terminates your employment for cause (as
            defined below), you will forfeit any and all payments that you would
            be entitled to under this agreement.

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         3. For the purposes of this agreement, "cause" shall be determined by
            the company in the exercise of good faith and reasonable judgment
            and will include any breach of this agreement by you or any act by
            you of gross personal misconduct, insubordination, misappropriation
            of funds, fraud, dishonesty, gross neglect of or failure to perform
            the duties reasonably required of you pursuant to this agreement or
            any conduct which is in willful violation of any applicable law or
            regulation pertaining to the business.

         4. For purposes of this agreement, we agree that Trex Medical will be
            considered to be sold when any person or entity (other than a person
            or entity affiliated with Thermo Electron) purchases at least fifty
            percent (50%) of the assets of the business, whether through a
            purchase of the business or a purchase of the company of which the
            business is a part.

         5. You understand that all payments made under this agreement are
            subject to appropriate federal, state, city or other tax withholding
            requirements.

         6. You acknowledge that this agreement supersedes any prior agreements
            or understandings oral or written between you and Trex Medical
            pertaining to any incentive payments being offered to employees of
            businesses being sold in connection with the reorganization and that
            this agreement constitutes the entire agreement between us.

On behalf of Thermo Electron and Trex Medical, I thank you for your continued
assistance and support. If you have any questions regarding any of the terms of
this agreement, please do not hesitate to contact me.

Once you have read and understood the terms of this agreement, please indicate
your agreement by signing below on the line above your typewritten name, make a
copy for your records and return the original document to me.

                                          Very truly yours,


                                          Jack Keiser, COO

Accepted and agreed:



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Jerry Roda                                       Date