AMERICAN SHARED HOSPITAL SERVICES
ADDENDUM TO 11/01/99 GAMMA KNIFE LEASE AGREEMENT
<DOCUMENT>
<TYPE>EX-10.34
<SEQUENCE>4
<FILENAME>f74683ex10-34.txt
<DESCRIPTION>ADDENDUM TO 11/01/99 GAMMA KNIFE LEASE AGREEMENT
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                                                                   Exhibit 10.34

                                    ADDENDUM

                    TO LEASE AGREEMENT FOR A GAMMA KNIFE UNIT


       This ADDENDUM TO LEASE AGREEMENT FOR A GAMMA KNIFE UNIT (this "Addendum")
is effective November 1, 1999 between Jackson HMA, Inc. dba Central Mississippi
Medical Center, a for profit Mississippi Corporation ("Medical Center"), and GK
Financing, LLC, a California limited liability company ("GKF").

                                    RECITALS

       WHEREAS, on November 1, 1999, GKF and Medical Center executed a Lease
Agreement for a Gamma Knife Unit (the "Original Lease");

       WHEREAS, the parties desire to amend the terms and provisions of the
Original Lease as set forth herein.

       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 hereby acknowledged, the parties agree as follows:

                                    AGREEMENT

       1. DEFINED TERMS. Unless otherwise defined herein, the capitalized terms
used herein shall have the same meaning set forth in the Original Lease.

       2. PREVIOUS MODIFICATIONS TO THE ORIGINAL LEASE. The manual
insertions/deletions/cross-outs made prior to this date on the Original Lease
and not counter-signed by GKF are null and void and non-binding on the Medical
Center and GKF. Said insertions/deletions/cross-outs, which are non-binding, are
in Sections 1, 5, 9 and 19.

       3. EVENTS OF DEFAULT BY GKF.

              3.1 The following Sections are added to the Original Lease:

                     3.1.1 GKF shall fail to observe or perform any of its
covenants, duties or obligations arising under this Agreement and such failure
shall continue for a period of thirty (30) days after written notice thereof is
given by Medical Center to GKF; however, if GKF cures the default within the
applicable thirty (30) day period or if the default reasonably requires more
than thirty (30) days to cure, GKF commences to cure the default during the
initial thirty (30) day period and GKF diligently completes the cure as soon as
reasonably possible following the end of the thirty (30) day period, such
default shall not constitute an Event of Default.


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                     3.1.2 GKF ceases doing business as a going concern, makes
an assignment for the benefit of creditors, admits in writing its inability to
pay its debts as they become due, files a voluntary petition in bankruptcy, is
adjudicated a bankrupt or an insolvent, files a petition seeking for itself any
reorganization, arrangement, composition, readjustment, liquidation, dissolution
or similar arrangement under any present or future statute, law or regulation or
files an answer admitting the material allegations of a petition filed against
it in any such proceeding, consents to or acquiesces in the appointment of a
trustee, receiver, or liquidator of it or of all or any substantial part of its
assets or properties, or it or its shareholders shall take any action looking to
its dissolution or liquidation.

                     3.1.3 Within sixty (60) days after the commencement of any
proceedings against GKF seeking reorganization, arrangement, readjustment,
liquidation, dissolution or similar relief under any present or future statute,
law or regulation, such proceedings shall not have been dismissed, or if within
thirty (30) days after the appointment without GKF's consent or acquiescence of
any trustee, receiver or liquidator of it or of all or any substantial part of
its assets and properties, such appointment shall not be vacated.

              3.2 Upon the occurrence of an Event of Default involving GKF,
Medical Center may at its option do any or all of the following:

                     3.2.1 By written notice to GKF, immediately terminate this
Agreement as to the Equipment and, in such event, GKF shall remove the Equipment
at GKF's sole cost and expense or, in the absence of removal by GKF within a
reasonable period of time after a written request therefor, Medical Center may
remove the Equipment with all due care and store the Equipment at GKF's sole
cost and expense.

                     3.2.2 Seek to recover from GKF such loss as may be realized
by Medical Center in the ordinary course of events as a result of the Event of
Default.

              3.3 GKF shall in any event remain fully liable for reasonable
damages as provided by law and for all costs and expenses incurred by Medical
Center on account of such default, including but not limited to, all court costs
and reasonable attorneys' fees. However, notwithstanding anything to the
contrary set forth in this Agreement, GKF shall not in any manner be or become
liable to Medical Center for any consequential or incidental damages that may be
suffered by Medical Center which arise out of or result from the Event of
Default or any breach by GKF of this Agreement. The rights and remedies afforded
Medical Center under this Agreement shall be deemed cumulative and not exclusive
and shall be in addition to any other rights or remedies to GKF provided by law
or in equity.

              3.4 Notwithstanding the occurrence of an Event of Default with
respect to GKF (including any claim which would otherwise be in the nature of a
set-off), Medical Center shall fully perform and pay its obligations hereunder
(including payment of all rent). Upon termination of this Agreement or the
exercise of any other rights or remedies under this Agreement or applicable law
following an Event of Default, Medical Center shall, without


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further request or demand, pay to GKF all rent payments and other sums owing
under this Agreement when and as due.

       4. INDEMNIFICATION.

              4.1 Medical Center's Indemnity Agreement. Subject to provisions of
this Agreement, Medical Center, for itself and its successors and assigns,
hereby indemnifies and holds GKF harmless from and against any loss, cost or
expense (including reasonable attorneys' fees) arising out of or relating in any
manner to the failure of Medical Center to properly perform any of its
obligations to be performed under the terms of this Agreement.

              4.2 GKF's Indemnity Agreement. Subject to provisions of this
agreement, GKF, for itself and its successors and assigns, hereby indemnifies
and holds Medical Center harmless from and against any loss, cost or expense
(including reasonable attorneys' fees) arising out of or relating in any manner
to the failure of GKF to properly perform any of its obligations to be performed
under the terms of this Agreement.

       5. FULL FORCE AND EFFECT. Except as otherwise amended hereby or provided
herein, all of the terms and provisions of the Original Lease shall remain in
full force and effect.


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       IN WITNESS WHEREOF, the parties have executed this Addendum effective as
of the date first written above.

               "MEDICAL CENTER"     Jackson HMA, Inc. dba
                                    Central Mississippi Medical Center



               BY:                  /s/ Jay R. Finnegan
                                    -------------------



               "GKF"                GK Financing, LLC



               BY:                  /s/ Craig K. Tagawa
                                    -------------------
                                    Craig K. Tagawa, Chief Executive Officer

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