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                                                                    Exhibit 4.24


                                February 29, 2000


Vision TwentyOne, Inc.
7360 Bryan Dairy Road, Suite 200
Largo, FL 33777

Attention:        Theodore Gillette, Chief Executive Officer


Gentlemen:

         We refer to the Amended and Restated Credit Agreement dated as of July
1, 1998, as amended, between you and us (the "Credit Agreement"). All
capitalized terms used herein without definition shall have the same meaning
herein as such terms are defined in the Credit Agreement.

         The Borrower has advised the Banks that the Borrower has entered into
an Agreement and Plan of Merger and Reorganization, dated as of February 10,
2000 (the "Merger Agreement"), among the Borrower, Opticare Health Systems, Inc.
(the "Parent"), and OC Acquisition Corp., a whollyowned subsidiary of the Parent
("Merger Sub"), pursuant to which the parties intend to merge Merger Sub with
and into the Borrower subject to the terms and conditions thereof which include,
among other things, restructuring the Obligations owing to the Banks on terms
and conditions mutually agreed upon by the Borrower and the Banks. While the
Borrower and the Banks have initiated discussions and due diligence concerning
the Merger and any proposed restructuring of the Obligations, the Borrower
acknowledges that the Banks have not consented to the Merger nor have the Banks
agreed to any terms and conditions relating to any restructuring of the
Obligations. In the meantime, however, the Borrower intends to continue to sell
a substantial number of the physician practice management groups operated by the
Borrower and its Subsidiaries (collectively being referred to herein as the "PPM
Businesses") and use a portion of the proceeds from the sale of the PPM
Businesses to meet its reasonable and necessary operating expenses.

         To afford the Borrower an opportunity to proceed with the transactions
described above, the Borrower has requested that the Banks extend the temporary
waiver period provided for in Sections 2.1 and 2.2 of that certain Seventh
Amendment and Waiver to Credit Agreement dated as of December 10, 1999 among the
Borrower, the Banks, and the Agent (the "Seventh Amendment") (as further
amended, in part, by a December 30, 1999 letter agreement between the Borrower,
the Banks and the Agent) from February 29, 2000, to the earlier of March 24,
2000, or the termination of the Merger Agreement pursuant to its terms (the
earlier of such dates being referred to herein as the "Waiver Termination Date")
and postpone the due date for the payment of principal and interest otherwise
due on February 29, 2000, and of interest otherwise due on February 29, 2000, to
the Waiver Termination Date. By signing below, the Banks hereby agree




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Vision Twenty-One, Inc.
February 29, 2000
Page 2

to extend the waiver period provided in Sections 2.1 and 2.2 of the Seventh
Amendment from February 29, 2000, to the Waiver Termination Date, and agree to
postpone the due date for the payment of principal and interest otherwise due on
February 29, 2000, and of interest otherwise due on February 29, 2000, to the
Waiver Termination Date, provided that:

                   (a) the Borrower agrees to promptly provide to the Banks
         copies of any instruments and documents entered into or proposed to be
         entered into in connection with the Merger (including, without
         limitation, any executed shareholder lock-up agreements) and to
         promptly advise the Banks of any termination, amendment, or waiver of
         the Merger Agreement or of any material breach thereof by any party
         thereto, in each case subject to its directors' fiduciary duties;

                   (b) until the Obligations are paid in full, the Borrower
         shall provide to the Banks a weekly Budget pursuant to Section 1.14(f)
         of the Credit Agreement and such Budget shall be subject to the
         Approved Budget and reconciliation procedures set forth therein,
         regardless of whether or not then being accompanied by a request for a
         Borrowing of Bridge Loans;

                   (c) at all times on and after the date hereof (i) all
         proceeds from the sale of any assets of the Borrower and its
         Subsidiaries (including, without limitation, proceeds from the sale of
         the PPM Businesses or any part thereof), and (ii) cash receipts arising
         from the operation of the business of the Borrower and its Subsidiaries
         not applied pursuant to an Approved Budget, shall in each case be
         remitted promptly upon receipt to the Agent; and

                   (d) except to the extent applied to payments pursuant to an
         Approved Budget or applied to the Obligations owing to the Banks,
         proceeds received pursuant to clause (c) above shall be held by the
         Agent as collateral for the remaining Obligations owing to the Banks
         (the Agent hereby being granted a Lien on and right of set-off for the
         benefit of the Banks against all such amounts so held).

The Borrower hereby acknowledges and agrees to the foregoing conditions. The
Borrower also hereby acknowledges and agrees that (i) the consummation of the
Merger and of any restructuring of the terms and conditions relating to the
Obligations shall in each case be subject to the Banks' consent, which may be
given or withheld in their discretion and (ii) any sale of the Borrower's or its
Subsidiaries' assets or businesses shall be subject to the prior written consent
of the Banks, and all proceeds from any such sale represent proceeds of the
Banks' Collateral, to be held by the Agent or applied to the Obligations
pursuant to the terms of the Credit Agreement as modified hereby.




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Vision Twenty-One, Inc.
February 29, 2000
Page 3

         Except as specifically modified hereby, all of the terms and conditions
of the Credit Agreement and the other Loan Documents shall stand and remain
unchanged and in full force and effect. This waiver shall become effective upon
the execution and delivery hereof by each of the Banks and the Borrower as set
forth below. This waiver may be executed in counterparts and by different
parties on separate counterpart signature pages, each of which shall be an
original and all of which taken together shall constitute one and the same
instrument. This waiver shall be governed by, and construed in accordance with,
the laws of the State of Illinois.

                           [SIGNATURE PAGES TO FOLLOW]























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Vision Twenty-One, Inc.
February 29, 2000
Page 4

         This waiver letter is entered into by and among the parties hereto as
of the date first above written.


BANK OF MONTREAL, in its individual          BANK ONE TEXAS, N.A.
capacity as a Bank and as Agent
                                             By: /s/ Ronnie Kaplan
By: /s/ Jack J. Kane                             Name:  Ronnie Kaplan
    Name:  Jack J. Kane                          Title: Vice President
    Title: Director

PACIFICA PARTNERS I, L.P.                    PILGRIM PRIME RATE TRUST

By: Imperial Credit Asset Management, as     By: Pilgrim Investments, Inc.,
    its Investment Manager                       as its Investment Manager

By: /s/ Dean K. Kawai                        By: /s/ Charles E. LeMieux
    Name:  Dean K. Kawai                         Name:  Charles E. LeMieux CFA
    Title: Vice President                        Title: Assistant Vice President

PILGRIM AMERICA HIGH INCOME                  MERRILL LYNCH BUSINESS FINANCIAL
INVESTMENTS LTD.                             SERVICES, INC.

By: Pilgrim Investments, Inc., as its        By: /s/ Gary L. Stewart
    Investment Manager                           Name:  Gary L. Stewart
                                                 Title: Vice President
By: /s/ Charles E. LeMieux
    Name:  Charles E. LeMieux, CFA
    Title: Assistant Vice President

         Acknowledged and agreed to as of the date first above written.

                                             VISION TWENTY-ONE, INC.

                                             By: /s/ Theodore N. Gillette
                                                 Name:  Theodore N. Gillette
                                                 Title: CEO