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                                                                 EXHIBIT 10.9(a)

                            FIRST AMENDMENT TO LEASE

THIS FIRST AMENDMENT TO LEASE (hereinafter "Amendment") is made this 8th day of
July 1996, by and between McCANDLESS LIMITED, a California limited partnership
(Landlord") and ENVISION SURGICAL SYSTEMS, INC., a California corporation doing
business as Novacept ("Tenant").

                                    RECITALS

                  A. Tenant currently leases from Landlord approximately eight
         thousand six hundred and fifty (8,650) square feet of space located at
         1047 Elwell Court, Palo Alto, California (the 'Premises") pursuant to
         that certain lease dated August 26, 1993 ("Lease").

                  B. The Lease provides for a termination date of August 25,
         1996.

                  C. Tenant desires to extend the term of the Lease pursuant to
         paragraph 56 of the Lease and Landlord is willing to extend the term of
         the Lease on the terms and conditions set forth herein.

NOW, THEREFORE, in consideration of the above recitals and the mutual covenants
and agreements contained herein and other good and valuable consideration the
receipt and sufficiency of which are hereby acknowledged, the parties hereby
agree as follows:

                  1. Term. The term of the Lease is hereby extended for an
additional two (2) years and six (6) days, so that the term of the Lease shall
extend to and include August 31, 1998. The period commencing on August 26, 1996
and ending on August 31, 1998 is referred to herein as the First Extended Term.

                  2. Basic Rent. Paragraphs 4 (a) and 5 of the Lease are hereby
amended to provide that the amount of basic rent due and payable under the Lease
during the First Extended Term shall be Eleven Thousand Ninety-Three and 63/100
Dollars ($11,093.63) per month from September 1, 1996 until August 31, 1997 and
Eleven Thousand Five Hundred and Four and 50/100 Dollars ($11,504.50) per month
from September 1, 1997 until August 31, 1998 as described below:

September 1, 1996 until August 31, 1997       $11,093.63/mo.

September 1, 1997 until August 31, 1998       $11,504.50/mo.

The basic rent during the last six days of August, from August 26, 1996 to
August 31, 1996, shall be one thousand six hundred forty-three and 50/100
Dollars ($1,643.50), the prorated share of August, 1996 basic rent at the rate
of $8,217.50 per month prevailing during the last lease month of the original
Lease.

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                  3. Restatement of Other Lease Terms. Except as specifically
modified herein, all other terms, covenants and conditions of the Lease,
including Tenant's obligation to pay common area charges, shall remain in full
force and effect.

                  4. Landlord's Address. For purposes of notification as
provided in paragraph 38 of the Lease, Landlord's address is hereby changed to:

                                        McCandless-Simons
                                        P.O. Box 872
                                        Los Altos, CA 94023-0872

IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the
day and year first above written.

                         LANDLORD:

                         McCANDLESS LIMITED,
                         a California limited partnership

                         By: /s/ Charles S. McCandless
                         ---------------------------------------------------
                                        Charles S. McCandless, as Trustee
                                        under the Charles S.McCandless and
                                        Jean A. McCandless Inter Vivos Trust
                                        Agreement dated January 25, 1977, a
                                        General Partner
                                           7-8-96
                         ---------------------------------------------------
                                            (Date)

                         TENANT:

                         ENVISION SURGICAL SYSTEMS, INC.,
                         a California corporation, dba Novacept.

                         By: /s/ Csaba Truckai
                         ---------------------------------------------------
                                  (Signature)

                                 CSABA TRUCKAI
                         ---------------------------------------------------
                                  (Printed Name)

                               V. P. OF R. & D.
                         ---------------------------------------------------
                                  (Title)

                                  07.01.96
                         ---------------------------------------------------
                                    (Date)

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