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                                                               Exhibit 3.2.3


                          XOMED SURGICAL PRODUCTS, INC.

                       Incorporated Under the Laws of the
                                State of Delaware

                                RESTATED BY-LAWS




                                    ARTICLE I

                                    OFFICES.

          Xomed Surgical Products, Inc. (the "Corporation") shall maintain a
registered office in the State of Delaware. The Corporation may also have other
offices at such other places, either within or without the State of Delaware, as
the Board of Directors may from time to time designate or the business of the
Corporation may require.


                                   ARTICLE II

                                  STOCKHOLDERS.

          Section 1. Annual Meeting. The annual meeting of Stockholders for the
election of Directors and the transaction of any other business as may properly
come before such meeting shall be held on a date fixed from time to time by the
Board of Directors within the thirty-one day period ending five months after the
end of the Corporation's fiscal year in such City and State and at such time
within such period and such place as may be designated by the Board of
Directors, and set forth in the notice of such meeting. At the annual meeting
any business may be transacted and any corporate action may be taken, whether
stated in the notice of meeting or not, except as otherwise expressly provided
by statute or the Corporation's Restated Certificate of Incorporation.

          Section 2. Special Meetings. Special meetings of the Stockholders for
any purpose may be called at any time by the Board of Directors, the Chairman of
the Board, or if no Chairman has been elected, by the President and Chief
Executive Officer, and shall be called by the Chairman of the Board or, if none,
by the President and Chief Executive Officer at the request of the holders of
thirty percent (30%) of the outstanding shares of capital stock entitled to
vote. Special meetings shall be held at such place or places within or without
the State of Delaware as shall from time to time be designated by the Board of
Directors and stated in the notice of such meeting. At a special meeting no
business shall be transacted and no corporate action shall be taken other than
that stated in the notice of the meeting.




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          Section 3. Notice of Meetings. Written notice of the date, time and
place of any Stockholders' meeting, whether annual or special, shall be given to
each Stockholder entitled to vote thereat, by mailing the same to him at his
address as the same appears upon the records of the Corporation not less than
ten (10) nor more than sixty (60) days prior to the date of such meeting. Notice
of any adjourned meeting need not be given other than by announcement at the
meeting so adjourned, unless otherwise ordered in connection with such
adjournment. Such further notice, if any, shall be given as may be required by
law.

          Section 4. Waiver of Notice. Notice of meeting need not be given to
any Stockholder who submits a signed waiver of notice, in person or by proxy,
whether before or after the meeting. The attendance of any Stockholder at a
meeting, in person or by proxy, without protesting prior to the conclusion of
the meeting the lack of notice of such meeting, shall constitute a waiver of
notice by him.

          Section 5. Quorum. Any number of Stockholders, together holding at
least a majority of the capital stock of the Corporation issued and outstanding
and entitled to vote, who shall be present in person or by proxy at any meeting
duly called, shall constitute a quorum for all purposes except as may otherwise
be provided by law.

          Section 6. Adjournment of Meetings. If less than a quorum shall attend
at the time for which a meeting shall have been called, the meeting may be
adjourned from time to time by a majority vote of the Stockholders present or by
proxy and entitled to vote thereat, without notice other than by announcement at
the meeting until a quorum shall attend. Any meeting at which a quorum is
present may also be adjourned in like manner and for such time or upon such call
as may be determined by a majority vote of the Stockholders present in person or
by proxy and entitled to vote thereat. At any adjourned meeting at which a
quorum shall be present, any business may be transacted and any corporate action
may be taken which might have been transacted at the meeting as originally
called.

          Section 7. Voting. Each Stockholder entitled to vote at any meeting
may vote either in person or by proxy, duly appointed by instrument in writing
subscribed by such Stockholder and bearing a date not more than eleven (11)
months prior to said meeting, unless said proxy provides for a longer period.
The holders of Common Stock shall be entitled to one (1) vote in respect of each
share held, and the holders of shares of Series A Convertible Preferred Stock
shall be entitled to the number of votes equal to the number of shares of Common
Stock into which such shares of Series A Convertible Preferred Stock are
convertible, on all matters submitted to a vote of shareholders. Except as
otherwise provided by law, in the Restated Certificate




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of Incorporation or in these By-laws, the holders of shares of Common Stock and
the holders of shares of Series A Preferred Stock shall vote together as a
single class. At all meetings of Stockholders, all matters, except as otherwise
provided by law, the Restated Certificate of Incorporation or these By-laws,
shall be determined by a majority vote of the Stockholders present in person or
by proxy and entitled to vote thereat. Except as otherwise provided by law, the
Restated Certificate of Incorporation or these By-laws, the holders of
Non-Voting Common Stock, Series B Convertible Preferred Stock and Series C
Redeemable Preferred Stock shall not be entitled to notice of, or to vote at,
any meeting of the stockholders of the Corporation nor to vote upon any matter
relating to the business or affairs of the Corporation.

          Section 8. Action by Stockholders Without a Meeting. Whenever under
the General Corporation Law of Delaware Stockholders are required or permitted
to take any action by vote, such action may be taken without a meeting upon
written consent, setting forth the action so taken, signed by the holders of
outstanding shares having not less than the minimum number of votes that would
be necessary to authorize or take such action at a meeting at which all shares
entitled to vote thereon were present and voted and shall be delivered to the
Corporation by delivery to its registered office in the State of Delaware, its
principal place of business, or an officer or agent of the Corporation having
custody of the book in which proceedings of meetings of stockholders are
recorded.


                                   ARTICLE III

                                   DIRECTORS.

          Section 1. Number and Qualifications. The Board of Directors shall
consist initially of seven (7) Directors, and thereafter shall consist of such
number as may be fixed from time to time by resolution of the Board of
Directors. The Directors need not be Stockholders.

          Section 2. Responsibilities. The general management of the affairs of
the Corporation shall be vested in the Board of Directors, which may delegate to
Officers, employees and to committees of three (3) or more Directors such powers
and duties as it may from time to time see fit, subject to the limitations
hereinafter set forth, and except as may otherwise be provided by law.

          Section 3. Election and Term of Office. The Directors shall be elected
by the Stockholders at the annual meeting of Stockholders. If the election of
Directors shall not be held on the day designated by the By-laws, the Directors
shall cause the same to be held as soon thereafter as may be convenient. The
Directors chosen at any annual meeting shall hold office except






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as hereinafter provided, until the next annual election and until the election
and qualification of their successors.

          Section 4. Removal and Resignation of Directors. Any Director may be
removed from the Board of Directors, with or without cause, by the holders of a
majority of the shares of outstanding stock entitled to vote at any special
meeting of the Stockholders called for that purpose, and the office of such
Director shall forthwith become vacant. Any Director may resign at any time.
Such resignation shall take effect at the time specified therein, and if no time
be specified, at the time of its receipt by the Chairman of the Board or if no
Chairman has been elected, by the President and Chief Executive Officer, or by
the Secretary. The acceptance of a resignation shall not be necessary to make it
effective, unless so specified therein.

          Section 5. Filling of Vacancies. Any vacancy among the Directors,
occurring from any cause whatsoever, may be filled by a majority of the
remaining Directors, though less than a quorum, provided, however, that the
Stockholders removing any Director may at the same meeting fill the vacancy
caused by such removal, and provided further, that if the Directors fail to fill
any such vacancy, the Stockholders may at any special meeting called for that
purpose fill such vacancy. In case of any increase in the number of Directors,
the additional Directors may be elected by the Directors in office prior to such
increase. Any person elected to fill a vacancy shall hold office, subject to the
right of removal as hereinbefore provided, until the next annual election and
until the election and qualification of his successor.

          Section 6. Regular Meetings. The Board of Directors shall hold an
annual meeting for the purpose of organization and the transaction of any
business immediately after the annual meeting of the Stockholders, provided a
quorum is present. Other regular meetings may be held at such times as may be
determined from time to time by resolution of the Board of Directors.

          Section 7. Special Meetings. Special meetings of the Board of
Directors may be called at any time by the Chairman of the Board of Directors,
if any, or by the President and Chief Executive Officer.

          Section 8. Notice and Place of Meetings. Regular meetings of the Board
of Directors may be held without notice at such time and place as shall be
designated by resolution of the Board of Directors. Notice shall be required,
however, for special meetings. Notice of any special meeting shall be
sufficiently given if mailed to each Director at his residence or usual place of
business at least five (5) days before the day on which the meeting is to be
held, or if sent to him at such place by telegraph or cable, or delivered
personally or by telephone not later than 24 hours prior to the time at which
the meeting is to be held. No notice of the annual meeting shall be required if





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held immediately after the annual meeting of the Stockholders and if a quorum is
present. Notice of a meeting need not be given to any Director who submits a
signed waiver of notice before or after the meeting, nor to any Director who
attends the meeting without protesting the lack of notice prior thereto or at
its commencement.

          Section 9. Business Transacted at Meetings. Any business may be
transacted and any corporate action may be taken at any regular or special
meeting of the Board of Directors at which a quorum shall be present, whether
such business or proposed action be stated in the notice of such meeting or not,
unless special notice of such business or proposed action shall be required by
law.

          Section 10. Quorum. A majority of the entire Board of Directors shall
be necessary to constitute a quorum for the transaction of business, and the
acts of a majority of the Directors present at a meeting at which a quorum is
present shall be the acts of the Board of Directors, unless otherwise provided
by law, the Restated Certificate of Incorporation or these By-laws. If a quorum
is not present at a meeting of the Board of Directors, a majority of the
Directors present may adjourn the meeting to such time and place as they may
determine without notice other than announcement at the meeting until enough
Directors to constitute a quorum shall attend. When a quorum is once present to
organize a meeting, it is not broken by the subsequent withdrawal of any
Directors.

          Section 11. Action Without A Meeting. Any action required or permitted
to be taken by the Board of Directors or any committee thereof may be taken
without a meeting if all members of the Board or the committee consent in
writing to the adoption of a resolution authorizing the action. The resolution
and the written consents thereto by the members of the Board or committee shall
be filed with the minutes of the proceedings of the Board or committee.

          Section 12. Participation By Telephone. Any one or more members of the
Board or any committee thereof may participate in a meeting of the Board or such
committee by means of a conference telephone or similar communications equipment
allowing all persons participating in the meeting to hear each other at the same
time. Participation by such means shall constitute presence in person at a
meeting.

          Section 13. Compensation. The Board of Directors may establish by
resolution reasonable compensation of all Directors for services to the
Corporation as Directors, including a fixed fee, if any, incurred in attending
each meeting, Nothing herein contained shall preclude any Director from serving
the Corporation in any other capacity, as an Officer, agent or otherwise, and
receiving compensation therefor.






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                                   ARTICLE IV

                                   COMMITTEES.

          Section 1. Appointment of Committees. Committees, whose members are to
be Directors, may be appointed by the Board of Directors, which committees shall
hold office for such time and have such powers and perform such duties as may
from time to time be assigned to them by the Board of Directors or the committee
appointing them. Any member of such a committee may be removed at any time, with
or without cause, by the Board of Directors or the committee appointing such
committee. Any vacancy in a committee occurring from any cause whatsoever may be
filled by the Board of Directors or the committee appointing such committee.

          Section 2. Resignation. Any member of a committee may resign at any
time. Such resignation shall be made in writing and shall take effect at the
time specified therein, or, if no time be specified, at the time of its receipt
by the Chairman of the Board, if any, the President and Chief Executive Officer
or the Secretary. The acceptance of a resignation shall not be necessary to make
it effective unless so specified therein.

          Section 3. Quorum. A majority of the members of a committee shall
constitute a quorum. The act of a majority of the members of a committee present
at any meeting at which a quorum is present shall be the act of such committee.
The members of a committee shall act only as a committee, and the individual
members thereof shall have no powers as such.

          Section 4. Record of Proceedings. Each committee shall keep a record
of its acts and proceedings, and shall report the same to the Board of Directors
when and as required by the Board of Directors.

          Section 5. Organization, Meetings and Notices. A committee may hold
its meetings at the principal office of the Corporation, or at any other place
upon which a majority of the committee may at any time agree. Each committee may
make such rules as it may deem expedient for the regulation and carrying on of
its meetings and proceedings.

          Section 6. Compensation. The members of any committee shall be
entitled to such compensation as may be established by resolution of the Board
of Directors.





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                                    ARTICLE V

                                    OFFICERS.

          Section 1. Number. The Officers of the Corporation shall be a
President and Chief Executive Officer, a Secretary and a Treasurer, and such
Vice Presidents and other Officers as may be appointed in accordance with the
provisions of Section 3 of this Article V. The Board of Directors, in its
discretion, may also elect a Chairman of the Board of Directors.

          Section 2. Election, Term of Office and Qualifications. The Officers,
except as provided in Section 3 of this Article V, shall be chosen annually by
the Board of Directors. Each such Officer shall, except as herein otherwise
provided, hold office until the selection and qualification of his successor.
Any two or more offices may be held by the same person, except the offices of
President and Chief Executive Officer and Secretary.

          Section 3. Other Officers. Other Officers, including, without
limitation, one or more Vice Presidents, Assistant Secretaries and Assistant
Treasurers, may from time to time be appointed by the Board of Directors, which
other Officers shall have such powers and perform such duties as may be assigned
to them by the Board of Directors or the Officer or committee appointing them.
All such Officers shall be corporate officers of the Corporation with the power
to bind the Corporation by acts within the scope of their authority.

          Section 4. Removal of Officers. Any Officer of the Corporation may be
removed from office, with or without cause, by a vote of a majority of the Board
of Directors.

          Section 5. Resignation. Any Officer of the Corporation may resign at
any time. Such resignation shall be in writing and shall take effect at the time
specified therein, and if no time be specified, at the time of its receipt by
the Chairman of the Board, if any, the President and Chief Executive Officer or
the Secretary. The acceptance of a resignation shall not be necessary in order
to make it effective, unless so specified therein.

          Section 6. Filling of Vacancies. A vacancy in any office shall be
filled by the Board of Directors.

          Section 7. Compensation. The compensation of the Officers shall be
fixed by the Board of Directors, or by any committee upon whom such power may be
conferred by the Board of Directors.

          Section 8. Chairman of the Board of Directors. The Chairman of the
Board of Directors, if one is elected, shall be a Director and shall preside at
all meetings of the Board of





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Directors and of the Stockholders at which he shall be present. He shall have
power to call special meetings of the Stockholders or of the Board of Directors
at any time and shall have such power and perform such other duties as may from
time to time be assigned to him by the Board of Directors.

          Section 9. President and Chief Executive Officer. The President and
Chief Executive Officer shall have responsibility for the general direction of
the business affairs and property of the Corporation, and of its several
Officers, and shall have and exercise all such powers and discharge such duties
as usually pertain to the office of President and Chief Executive Officer. He
shall have responsibility for the day-to-day affairs of the Corporation, subject
to the control of the Board of Directors. He shall perform such duties as may be
assigned to him from time to time by the Board of Directors and shall, in the
absence of the Chairman of the Board, perform and carry out the functions of the
Chairman of the Board.

          Section 10. Secretary. The Secretary shall attend all meetings of the
Board of Directors and of the Stockholders and record all votes and the minutes
of all proceedings in a book to be kept for that purpose, and shall perform like
duties for any committee appointed by the Board. He shall give or cause to be
given notice of all meetings of Stockholders and special meetings of the Board
of Directors and shall perform such other duties as may be prescribed by the
Board of Directors. He shall keep in safe custody the seal of the Corporation
and affix it to any instrument when so authorized by the Board of Directors.

          Section 11. Treasurer. The Treasurer shall have custody of the
corporate funds and securities and shall keep full and accurate accounts of
receipts and disbursements in books belonging to the Corporation and shall
deposit all moneys and other valuable effects in the name and to the credit of
the Corporation in such depositaries as may be designated by the Board of
Directors. He shall disburse the funds of the Corporation as may be ordered by
the Board, taking proper vouchers for such disbursements, and shall render to
the President and Chief Executive Officer and Directors at the regular meetings
of the Board, or whenever they may require it, an account of all his
transactions as Treasurer and of the financial condition of the Corporation. He
may be required to give bond for the faithful discharge of his duties.


                                   ARTICLE VI

                                 CAPITAL STOCK.

          Section 1. Issue of Certificates of Stock. Certificates of capital
stock shall be in such form as shall be approved by the Board of Directors. They
shall be numbered in the order of their issue, and shall be signed by the
Chairman of




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the Board of Directors, the President and Chief Executive Officer or any Vice
President, and by the Treasurer or any Assistant Treasurer or the Secretary or
any Assistant Secretary, and the seal of the Corporation or a facsimile thereof
shall be impressed, affixed or reproduced thereon. In case any Officer or
Officers who shall have signed any such certificate or certificates shall cease
to be such Officer or Officers of the Corporation, whether because of death,
resignation or otherwise, before such certificate or certificates shall have
been delivered by the Corporation, such certificate or certificates may
nevertheless be adopted by the Corporation and be issued and delivered as though
the person or persons who signed such certificate or certificates have not
ceased to be such Officer or Officers of the Corporation.

          Section 2. Registration and Transfer of Shares. The name of each
person owning a share of the capital stock of the Corporation shall be entered
on the books of the Corporation together with the number of shares held by him,
the numbers of the certificates covering such shares and the dates of issue of
such certificates. The shares of stock of the Corporation shall be transferable
on the books of the Corporation by the holders thereof in person, or by their
duly authorized attorneys or legal representatives, on surrender and
cancellation of certificates for a like number of shares, accompanied by an
assignment of power of transfer endorsed thereon or attached thereto, duly
executed, and with such proof of the authenticity of the signature as the
Corporation or its agents may reasonably require. A record shall be made of each
transfer. The Board of Directors may make other and further rules and
regulations concerning the transfer and registration of certificates for stock.

          Section 3. Lost, Destroyed and Mutilated Certificates. The holder of
any stock of the Corporation shall immediately notify the Corporation of any
loss, theft, destruction or mutilation of the certificates therefor. The
Corporation may issue a new certificate of stock in the place of any certificate
theretofore issued by it and alleged to have been lost, stolen or destroyed. The
Board of Directors may, in its discretion, require the owner of the lost, stolen
or destroyed certificate, or his legal representatives, to give the Corporation
a bond, in such sum not exceeding double the value of the stock and with such
surety or sureties as they may require, to indemnify it against any claim that
may be made against it by reason of the issue of such new certificate and
against all other liability in the premises, or may remit such owner to such
remedy or remedies as he may have under the laws of the State of Delaware.





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                                   ARTICLE VII

                             DIVIDENDS AND SURPLUS.

          The Board of Directors shall have power to fix and vary the amount to
be set aside or reserved as working capital of the Corporation, or as reserves,
or for other proper purposes of the Corporation, and, subject to the
requirements of the Restated Certificate of Incorporation, to determine whether
any part of the surplus or net profits of the Corporation shall be declared in
dividends and paid to the Stockholders, and to fix the date or dates for the
payment of dividends.


                                  ARTICLE VIII

                            MISCELLANEOUS PROVISIONS.


          Section 1. Fiscal Year. The fiscal year of the Corporation shall
commence on the first day of January and end on the last day of December.

          Section 2. Corporate Seal. The corporate seal shall be in such form as
approved by the Board of Directors and may be altered at its pleasure. The
corporate seal may be used by causing it or a facsimile thereof to be impressed,
affixed or reproduced by the Secretary or Assistant Secretary of the
Corporation.

          Section 3. Notices. Except as otherwise expressly provided, any notice
required by these By-laws to be given shall be sufficient if given by depositing
the same in a post office or letter box in a sealed wrapper with first class
postage prepaid thereon and addressed to the person entitled thereto at his
address, as the same appears upon the books of the Corporation, or by
telegraphing or cabling the same to such person at such address; and such notice
shall be deemed to be given at the time it is mailed, telegraphed or cabled.

          Section 4. Waiver of Notice. Any Stockholder or Director may at any
time, by writing or by telegraph or by cable, waive any notice required to be
given under these By-laws, and if any Stockholder or Director shall be present
at any meeting his presence shall constitute a waiver of such notice.

          Section 5. Contracts, Checks, Drafts. The Board of Directors, except
as may otherwise be required by law, may authorize any Officer or Officers,
agent or agents, in the name of and on behalf of the Corporation to enter into
any contract or execute or deliver any instrument. All checks, drafts or other
orders for the payment of money, notes or other evidences of indebtedness issued
in the name of the Corporation, shall be signed by such Officer or Officers,
agent or agents of the





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Corporation, and in such manner, as shall be designated from time to time by
resolution of the Board of Directors.

          Section 6. Deposits. All funds of the Corporation shall be deposited
from time to time to the credit of the Corporation in such bank or banks, trust
companies or other depositaries as the Board of Directors may select, and, for
the purpose of such deposit, checks, drafts, warrants and other orders for the
payment of money which are payable to the order of the Corporation, may be
endorsed for deposit, assigned and delivered by any Officer of the Corporation,
or by such agents of the Corporation as the Board of Directors, the Chairman of
the Board, if any, or the President and Chief Executive Officer may authorize
for that purpose.

          Section 7. Voting Stock of Other Corporations. Except as otherwise
ordered by the Board of Directors, the Chairman of the Board, if any, or the
President and Chief Executive Officer shall have full power and authority on
behalf of the Corporation to attend and to act and to vote at any meeting of the
stockholders of any corporation of which the Corporation is a stockholder and to
execute a proxy to any other person to represent the Corporation at any such
meeting, and at any such meeting the Chairman of the Board, if any, or the
President and Chief Executive Officer or the holder of any such proxy, as the
case may be, shall possess and may exercise any and all rights and powers
incident to ownership of such stock and which, as owner thereof, the Corporation
might have possessed and exercised if present. The Board of Directors may from
time to time confer like powers upon any other person or persons.

          Section 8. Indemnification of Officers and Directors. The Corporation
shall indemnify any and all of its Directors or Officers, who shall serve as an
Officer or Director of this Corporation or of any other corporation at the
request of this Corporation, to the fullest extent permitted under and in
accordance with the laws of the State of Delaware.


                                   ARTICLE IX

                                   AMENDMENTS.

          These By-laws may be amended or repealed, or new By-laws may be
adopted, at any annual or special meeting of the Stockholders, by vote of the
Stockholders entitled to vote in the election of Directors; provided, however,
that the notice of such meetings shall have been given as provided in these
By-laws, which notice shall mention that amendment or repeal of these By-laws,
or the adoption of new By-laws, is one of the purposes of such a meeting; and
provided, further, that By-laws adopted by the Stockholders shall not be
rescinded, altered, amended or repealed by the Board of Directors if such
By-laws adopted by the Stockholders so express. These By-laws may also be
amended or




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repealed, or new By-laws may be adopted, by the Board of Directors at any
meeting thereof; provided, however, that notice of such meeting shall have been
given as provided in these By-laws, which notice shall mention that amendment or
repeal of the By-laws, or the adoption of new By-laws, is one of the purposes of
such meeting; and provided further, that By-laws adopted by the Board of
Directors may be amended or repealed by the Stockholders as hereinabove
provided.


Dated:  February 5, 1997




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