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                                                                  EXHIBIT 10.24b

                           FIRST AMENDMENT TO SUBLEASE

THIS FIRST AMENDMENT TO SUBLEASE ("First Amendment") is made as of July 1, 2003
by and between Sorrento Montana, L.P., a California Limited Partnership
("Landlord") and Integra NeuroSciences CA Corporation, a Delaware Corporation
("Tenant"), with reference to the following facts and circumstances:

            Landlord and Camino NeuroCare, Inc. entered into a Sublease dated
            July 1, 2001 for approximately 16,205 square feet of premises
            commonly known as Suites #706 through #714 and Suite #716, 5965
            Pacific Center Boulevard, San Diego, California 92121 ("Premises").

Landlord and Tenant desire to modify, amend and supplement the Sublease through
this First Amendment as follows:

            1. Paragraph 1.3 ("TENANT") is hereby amended to delete Camino
            NeuroCare, Inc., a Delaware Corporation as Tenant and substitute
            therefore Integra Neurosciences CA Corporation, a Delaware
            Corporation as Tenant.

            2. Paragraph 1.5 ("SUBLEASE TERM") is hereby amended to extend the
            term of the Sublease an additional twenty-four months through June
            30, 2005.

            3. Paragraph 1.8 ("INITIAL SECURITY DEPOSIT") is hereby amended to
            provide for Tenant's Security Deposit to be increased by Ten
            Thousand Sixty-Four and 75/100 Dollars ($10,064.75), resulting in a
            Security Deposit of Fifteen Thousand Three Hundred Ninety-Four and
            75/100 Dollars ($15,394.75).

            4. Paragraph 1.9.1 ("BASE RENT") is amended to provide for payment
            by Tenant of Base Rent of Fifteen Thousand Three Hundred Ninety-Four
            and 75/100 Dollars ($15,394.75) per month effective July 1, 2003.
            Effective July 1, 2004 and every July 1 thereafter throughout the
            sublease term, Tenant's Base Rent shall be increased four percent
            (4%) over the Base Rent payable by Tenant for the immediately
            preceding month.

            5. Paragraph 14.0 ("OPTION TO RENEW") is hereby amended to provide
            Tenant an Option to Renew ("Renewal Option") this Sublease for one
            additional two-year term commencing July 1, 2005 and continuing for
            twenty-four consecutive months. Provided Tenant is not in default of
            this Sublease or Tenant's July 1, 2001 Sublease of 5955 Pacific
            Center Boulevard as subsequently amended, Tenant shall exercise the
            Renewal Option by notifying Landlord in writing on or before
            December 31, 2004 of Tenant's intention to renew. Tenant's Beginning
            Base Rent for the option term shall be ninety-five percent (95%) of
            the then-prevailing market rate for comparable space in the Sorrento
            Mesa/Sorrento Valley area, but in no event less than $1.03 NNN per
            square foot per month. Tenant's failure to exercise the Renewal
            Option on or before December 31, 2004 shall constitute a waiver of
            the Renewal Option by Tenant.

            6. Paragraph 17.0 ("OPTION TO RETURN PREMISES") is hereby added to
            provide Tenant with a one-time Option to Return and delete from this
            Sublease a portion of Tenant's Premises ("Return Option") upon
            thirty

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            days' advance written notification served to Landlord any one time
            during the period July 1, 2003 and November 30, 2003. The premises
            which Tenant may return under the Return Option are specifically
            limited to the approximately 1,203 square toot Suite #716 and/or any
            one (but not more than one) of the following:

                        i. Suite #706 (approximately 1,728 square feet)

                        ii.Suites #706 and #707 (approximately 3,456 square
                        feet)

                        iii.Suite #714 (approximately 1,618 square feet)

                        iv. Suites #714 and #713 (approximately 3,236 square
                        feet)

                        v. Suite #706 and #714 (approximately 3,346 square feet)

Thirty days following Landlord's receipt of Tenant's written notice specifically
identifying the suite or suites from the above list to be returned (which may be
served by Tenant any one time during the period July 1, 2003 and November 30,
2003 only), the identified suites shall be deleted from Section 1.4 ("Premises")
of this Sublease without penalty. Tenant's Base Rent payable under Paragraph
1.9.1 shall be reduced by $0.95 NNN per square foot per month for all square
footage of Premises returned under this Return Option effective thirty days from
Landlord's receipt of Tenant's written notice identifying the Premises to be
returned hereunder. The foregoing notwithstanding, Tenant, at Tenant's sole cost
and expense, shall be responsible for physically demising with a wall or walls
as necessary and separating as necessary the system or systems serving the
returned premises, including but not necessarily limited to electrical, heating,
ventilation and air conditioning, from the then-remaining portion of Tenant's
Premises.

                    Except as specifically provided in this First Amendment, all
of the terms, conditions and definitions set forth in the Sublease shall remain
unchanged and in full force and effect. In the event of any conflict between
this First Amendment and the Sublease, the terms of this First Amendment shall
prevail.

IN WITNESS WHEREOF, the parties hereto have executed this First Amendment To
Sublease effective the day and year first written above:

LANDLORD:                                              TENANT:

SORRENTO MONTANA, L.P., A                      INTEGRA NEUROSCIENCES CA
                                               CORPORATION
                                               A Delaware Corporation

A California Limited Partnership
By: Sorrento Commercial Properties, Inc.       By: /s/ Stuart M. Essig
A California Corporation doing business        ------------------------
as Sorrento Management Company                 Title: President and CEO

                                               Date:
By: /s/ Roger W. Hillbrook
    -------------------------------
    Roger W. Hillbrook
    Vice President/Corporate Broker

Date: 7/21/03

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