Exhibit 10.1 ADDENDUM TO CONVERTIBLE DEBENTURE AND WARRANT TO PURCHASE COMMON STOCK This addendum to Convertible Debenture and Warrant to Purchase Common Stock ("Addendum") is entered into as of the 9th day of February 2005 by and between Integrated...

                                                                    Exhibit 10.1


                      ADDENDUM TO CONVERTIBLE DEBENTURE AND
                        WARRANT TO PURCHASE COMMON STOCK

This addendum to Convertible Debenture and Warrant to Purchase Common Stock
("Addendum") is entered into as of the 9th day of February 2005 by and between
Integrated Surgical Systems, Inc., a Delaware corporation ("Integrated"), and
Golden Gate Investors, Inc., a California corporation ("GGI").

WHEREAS, GGI and Integrated are parties to that certain 6 3/4% Convertible
Debenture dated as of June 9, 2004 ("Debenture"); and

WHEREAS, GGI and Integrated are parties to that certain Warrant to Purchase
Common Stock dated June 9, 2004 ("Warrant"); and

WHEREAS, the parties desire to amend the Debenture and Warrant in certain
respects.

NOW, THEREFORE, in consideration of the mutual promises and covenants contained
herein, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, Integrated and GGI agree as
follows:

     1.   All terms used herein and not otherwise defined herein shall have the
          definitions set forth in the debenture.

     2.   The Deadline is hereby changed to be April 30, 2005.

     3.   The Conversion Price set forth in section 3.1(a) of the Debenture is
          hereby changed to be the lesser of: (i) $0.25, or (ii) seventy-five
          percent (75%) of the average of the five lowest Volume Weighted
          Average Prices during the 20 Trading Days prior to GGI's election to
          convert (a "Discount Multiplier").

     4.   Except as specifically amended herein, all other terms and conditions
          of the Debenture and Warrant shall remain in full force and effect.

IN WITNESS WHEREOF, Integrated and GGI have caused this Addendum to be signed by
its duly authorized officers on the date first set forth above.


Integrated Surgical Systems, Inc.           Golden Gate Investors, Inc.
/s/  XXXXXX  XXXXXXX                        /s/  XXXXXX XXXX
---------------------------------           ------------------------------------
Xxxxxx Xxxxxxx                              Xxxxxx Xxxx
President/CEO                               Portfolio Manager