Exhibit 10.24



November 15, 1999


Ronald G. Evens, M.D., President
Barnes-Jewish Hospital
One Barnes-Jewish Hospital Plaza
St. Louis, MO  63110

Dear Dr. Evens:

This letter agreement, which supersedes all other agreements and
renewals thereto on this subject is for the purpose of stating the
terms and conditions under which you agree to serve Mallinckrodt Inc.,
a Delaware corporation, (hereinafter MALLINCKRODT) in a consulting
capacity.

You agree to serve MALLINCKRODT in a consulting capacity during the
period commencing on January 1, 2000 and ending on December 31, 2000.
It is understood that you may terminate this Agreement at any time
upon thirty (30) days written notice to MALLINCKRODT and that
MALLINCKRODT may terminate this Agreement on ninety (90) days written
notice to you.

During the consulting period you shall serve as an advisor to
MALLINCKRODT and in that capacity you will review and evaluate the
research and development programs and plans of MALLINCKRODT and
provide such other advice and assistance in your general areas of
expertise as may be requested from time to time.  It is understood and
agreed that during the consulting period you will devote two (2) four
(4) hour days each month and such additional hours as may be mutually
agreed upon to the services of MALLINCKRODT.

As consideration for your services hereunder, MALLINCKRODT agrees to
pay you as follows:

     At an annual rate of Forty Thousand Eight Dollars ($40,008.00) in
     twelve (12) monthly installments of Three Thousand Three Hundred
     Thirty-Four Dollars ($3,334.00) each.

It is understood that MALLINCKRODT may designate places and locations
where you will provide your services in a consulting capacity and
where this requires you to travel away from St. Louis, Missouri,
MALLINCKRODT will reimburse you for the reasonable travel and living
expenses incurred by you upon submission by you and approval by
MALLINCKRODT of an itemized account of the expenses for which you seek
reimbursement.

You agree to maintain in confidence and not use except for purposes of
this consulting agreement any confidential information of a business
as well as of a technical nature, disclosed to you by MALLINCKRODT or
developed by you as a result of your services to MALLINCKRODT
hereunder.  Upon termination of this Agreement or any extensions
thereof or at any other time that MALLINCKRODT so requests, you also
agree to transmit to MALLINCKRODT any written, printed or other
materials embodying such confidential information including any copies
or excerpts thereof given to you or prepared by you in connection with
your consulting services for MALLINCKRODT.  It is understood and
agreed that this obligation of confidentiality and non-use shall
continue at all times beyond the consulting period and any extensions
thereof.  This obligation of confidentiality and non-use shall not
apply to information which (1) is or later becomes publicly known
under circumstances involving no breach of this Agreement by you; (2)
was already known to you at the time of receipt of such information
from MALLINCKRODT; or (3) is legally made available to you by a third
party.  Your obligations of confidentiality and non-use shall survive
the expiration or termination of this Agreement.

You agree that during the consulting period you will not enter into
any other consulting agreement in the radiopharmaceutical and contrast
media fields without the prior written consent of MALLINCKRODT which
consent shall not be unreasonably withheld.

It is understood and agreed that any and all inventions and
discoveries whether or not patentable which you conceive and/or make
within the consulting period and any extensions thereof and which
result from information received from MALLINCKRODT or are developed by
you pursuant to your services for MALLINCKRODT shall be the sole and
exclusive property of MALLINCKRODT and that you will upon request by
MALLINCKRODT promptly execute any and all applications, assignments or
other instruments which MALLINCKRODT shall deem necessary or useful in
order to apply for and obtain Letters Patent in the United States and
all other countries for said inventions and discoveries and in order
to assign and convey to MALLINCKRODT the sole and exclusive right,
title and interest in and to said inventions, discoveries, patent
applications and patents thereon.  It is understood that MALLINCKRODT
will bear the cost of preparation of all such patent applications and
assignments and the cost of the prosecution of all such patent
applications in the United States Patent Office and the patent offices
of other countries.

If the foregoing meets with your understanding and approval, please so
indicate by executing this letter in duplicate at the place indicated
below and returning one of the signed duplicates to me.

Very truly yours,                      ACCEPTED & AGREED TO:

MALLINCKRODT INC.                      RONALD G. EVENS, M.D.

By: /s/ C. R. Holman                    /s/ Ronald G. Evens
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   C.R. Holman,                         Dated   11-18-99
   Chief Executive Officer                    --------------------