Exhibit 10.16

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                            SIXTH AMENDMENT AGREEMENT
                            -------------------------

          SIXTH AMENDMENT  AGREEMENT (this "Agreement") dated as of December 31,
1996 by and among (1) Xomed Surgical Products,  Inc.  ("Holdings"),  (2) Merocel
Corporation ("Merocel"), (3) Xomed, Inc. ("Xomed"), (4) Xomed-Treace,  P.R. Inc.
("Xomed  P.R."),  (5) Trebay Medical  Corporation  ("Trebay" and,  together with
Holdings, Merocel, Xomed and Xomed P.R., collectively,  the "Borrowers" and each
singularly , a  "Borrower")  and (5) Bank of Boston  Connecticut  ("BKBCT")  and
certain  other  financial  institutions  which may  become a party to the Credit
Agreement (collectively,  the "Banks" and individually, a "Bank"), and (6) BKBCT
as agent (the "Agent") for the Banks, with respect to a certain Credit Agreement
dated as of April 15, 1994 by and among the Borrowers,  the Banks and the Agent,
as amended by a certain  First  Amendment  Agreement  dated  June 24,  1994,  an
Amendment and Waiver  Agreement  dated as of March 31, 1995, a Second  Amendment
and Waiver  Agreement  dated as of July 3, 1995,  a Third  Amendment  and Waiver
Agreement dated as of April 15, 1996, a Joinder  Agreement dated as of April 16,
1996, a Fourth  Amendment  and Waiver  Agreement  dated as of June 7, 1996 and a
Fifth  Amendment and Waiver  Agreement dated as of September 3, 1996 (as amended
from time to time, collectively, the "Credit Agreement").


                              W I T N E S S E T H:


          WHEREAS,  the Borrowers  have  requested  that the Banks and the Agent
amend certain terms and conditions of the Credit Agreement; and

          WHEREAS,  the Agent and the Banks are willing to amend  certain  terms
and  conditions of the Credit  Agreement on the terms and  conditions  set forth
herein.

          NOW, THEREFORE,  for good and valuable consideration,  the receipt and
sufficiency  of which are  hereby  acknowledged,  the  parties  hereto  agree as
follows:


           Section 1. Capitalized terms used herein without  definition that are
defined in the Credit Agreement shall have the same meanings herein as therein.

           Section 2. Ratification of Existing Agreements. All of the Borrowers'
obligations  and  liabilities  to the  Banks and the  Agent as  evidenced  by or
otherwise arising under the Credit Agreement, the Revolving Credit Notes and the
other Loan  Documents,  are, by each  Borrower's  execution  of this  Agreement,
ratified  and  confirmed  in all  respects.  In  addition,  by  each  Borrower's
execution of this  Agreement,  each  Borrower  represents  and warrants  that no
counterclaim,  right of set-off or defense of any kind exists or is  outstanding
with respect to such obligations and liabilities.

           Section 3. Representations and Warranties. All of the representations
and  warranties  made by the  Borrowers in the Credit  Agreement,  the Revolving
Credit  Notes  and the  other  Loan  Documents  (other  than  Section7.1(d)  and
Section7.12(a) with respect to Borrowers' 1995




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tax returns) are true and correct on the date hereof as if made on and as of the
date  hereof,  except  to the  extent of  changes  resulting  from  transactions
contemplated  or permitted by the Credit  Agreement and the other Loan Documents
and changes  occurring in the ordinary  course of business that singly or in the
aggregate  are  not  materially  adverse,  and to the  extent  that  any of such
representations and warranties relate expressly to an earlier date.


           Section 4. Conditions  Precedent. The effectiveness of the amendments
contemplated  hereby shall be subject to the  satisfaction on or before the date
hereof of each of the following conditions precedent:

          (a)  Representations  and Warranties.  All of the  representations and
warranties  made by the Borrowers  herein,  whether  directly or incorporated by
reference,  shall be true and correct on the date hereof,  except as provided in
 Section 3 hereof.

          (b)  Performance;  No Event  of  Default.  The  Borrowers  shall  have
performed and complied in all material  respects  with all terms and  conditions
herein  required to be performed or complied  with by it prior to or at the time
hereof, and there shall exist no Default or Event of Default.


          (c) Corporate Action. All requisite corporate action necessary for the
valid execution, delivery and performance by the Borrowers of this Agreement and
all other  instruments  and  documents  delivered by the Borrowers in connection
therewith shall have been duly and effectively taken.


          (d)  Delivery.  The parties  hereto shall have  executed and delivered
this  Agreement.  In addition,  the Borrowers  shall have executed and delivered
such  further  instruments,  and take such  further  action as the Agent and the
Banks may have reasonably requested, in each case further to effect the purposes
of this Agreement, the Credit Agreement and the other Loan Documents.


          (e) MFC  Agreements.  The Borrowers  shall have caused Merocel Funding
Corporation  ("MFC") to execute and deliver to the Banks and the Agent a written
agreement and  acknowledgment,  in form and substance  satisfactory to the Banks
and the Agent,  regarding the terms and conditions of this Agreement and each of
the other  Loan  Documents  and  MFC's  status  and  obligations  as a  Borrower
hereunder and under the other Loan Documents.

                    (f) Amendments to Loan Documents.  The Borrowers (including,
          without  limitation,  MFC) shall have  executed  and  delivered to the
          Agent a Second  Amended and Restated  Security  Agreement  and a Third
          Amended and Restated Revolving Credit Note, each in form and substance
          satisfactory  to the Agent and the Banks.  In  addition,  pursuant  to
          pledge, assignment and security agreements, each in form and substance
          satisfactory  to the Banks and the  Agent,  the  Borrowers  shall have
          caused  MFC to grant to the  Agent on  behalf of the Banks a valid and
          perfected first (subject only to Permitted Liens) security interest in
          all of its properties and assets. The Borrowers  acknowledge and agree
          that all of such security and pledge




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agreements  shall be included in the definition of Security  Documents under the
Credit Agreement.


                    (g)  Amendment to Merocel  Stock Pledge  Agreement.  Merocel
          shall have  executed and  delivered an amendment to the Merocel  Stock
          Pledge  Agreement to evidence the  Merocel's  pledge of all of the MFC
          Common  Stock  to the  Agent,  for  the  benefit  of the  Banks,  such
          amendment to be in form and  substance  satisfactory  to the Banks and
          the Agent.


                    (h) Fees and Expenses.  The Borrowers shall have paid to the
          Agent and Banks all fees and expenses  incurred by the Agent and Banks
          in connection with this Agreement,  the Credit  Agreement or the other
          Loan Documents on or prior to the date hereof.


                    (i)  Assignments.  Each  of  Bank  of  Scotland,  The  Chase
          Manhattan   Bank  and   Internationale   Nederlanden   (U.S.)  Capital
          Corporation shall have assigned all of their right, title and interest
          under the Credit  Agreement and the other Loan  Documents  pursuant to
          Assignment and  Acceptances  executed and delivered by each of Bank of
          Scotland,  The Chase  Manhattan  Bank and  Internationale  Nederlanden
          (U.S.) Capital Corporation to Bank of Boston Connecticut. In addition,
          each of Bank of Scotland,  The Chase Manhattan Bank and Internationale
          Nederlanden (U.S.) Capital  Corporation shall have (i) returned to the
          Agent their  respective  Amended and Restated  Revolving  Credit Notes
          marked  "canceled"  and (ii)  received  payment  from  Bank of  Boston
          Connecticut  of all  amounts due and payable to each of them under the
          Credit  Agreement  as of  the  date  hereof  in  connection  with  the
          assignments.


            Section 5.   Amendments to the Credit Agreement.
                 
                  (a)   Amendment to Preamble.  The Preamble to the Credit
 Agreement is hereby amended in its entirety:

                           "This CREDIT  AGREEMENT is made as of the 15th day of
                  April,  1994,  by and among MEROCEL  CORPORATION  ("Merocel"),
                  XOMED INC.  (formerly known as Xomed-Treace,  Inc.) ("Xomed"),
                  XOMED-TREACE,   P.R.,  INC.  ("Xomed  P.R."),  TREBAY  MEDICAL
                  CORPORATION   ("Trebay"),   XOMED  SURGICAL   PRODUCTS,   INC.
                  (formerly known as Merocel/Xomed Holdings,  Inc.) ("Holdings")
                  and MEROCEL  FUNDING  CORPORATION  ("MFC" and,  together  with
                  Merocel,   Xomed,  P.R.,  Xomed,  Trebay  and  Holdings,   the
                  "Borrowers"  and  each,  singularly,  a  "Borrower"),  each  a
                  Delaware  corporation  and BANK OF BOSTON  CONNECTICUT and the
                  other  lending  institutions  listed on  Schedule  1  attached
                  hereto   (collectively,   the  "Banks")  and  BANK  OF  BOSTON
                  CONNECTICUT  as agent for itself and the other  Banks (in such
                  capacity, the "Agent") as amended by a certain First Amendment
                  Agreement  dated  June  24,  1994,  an  Amendment  and  Waiver
                  Agreement  dated as of March 31, 1995, a Second  Amendment and
                  Waiver  Agreement  dated as of July 3, 1995, a Third Amendment
                  and Waiver  Agreement  dated as of April 15, 





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                   1996,  a Joinder  Agreement  dated as of April 16,  1996,  a
                   Fourth  Amendment and Waiver  Agreement  dated as of June 7,
                   1996, a Fifth  Amendment  and Waiver  Agreement  dated as of
                   September 3, 1996 and a Sixth  Amendment  Agreement dated as
                   of  December  31,  1996  (as  amended  from  time  to  time,
                   collectively, the "Credit Agreement")."


                   (b)   Amendment  to  Schedule  1.  Schedule  1 of the  Credit
 Agreement   is   hereby   amended   as   of   the   date   hereof   to read as 
 follows:

                                   "Schedule 1

                              Lending Institutions
                                                            COMMITMENT
 BANKS                            COMMITMENT                PERCENTAGE
 Bank of Boston Connecticut       $14,000,000.00            100.00%"
 81 West Main Street
 Waterbury, Connecticut



          (c) Amendment to Schedule 2 of the Credit Agreement. The following new
definitions are hereby added to Schedule 2 of the Credit Agreement:

                    "Receivable  Servicing  Agreement.  That certain Receivables
          Servicing  Agreement by and between  Xomed and MFC dated  December 31,
          1996."

                    "MFC. See the Preamble hereto."


          (d) Amendment to Schedule 2 of the Credit Agreement. The definition of
"Consolidated Financial Obligations" appearing on Page 4 of Schedule 2 is hereby
amended by adding the following at the end of such definition.

                    "The  Indebtedness  permitted  under  ss.9.1(k) shall not be
          included when calculating  Consolidated  Financial  Obligations  under
          ss.10.1 of the Credit Agreement."


          (e) Amendments to Section 6 of the Credit Agreement.  Section 6 of the
Credit  Agreement is hereby amended by adding the phrase "(other than Holdings)"
after the word "Borrower" appearing in the fourth line of such section.


          (f)  Amendment  to Section  7.1(d) and  Schedule  7.1(d) of the Credit
Agreement.  Section 7.1(d) and Schedule 7.1(d) of the Credit  Agreement are each
hereby amended in their entirety to read as follows:

                    "Intentionally Omitted."


          (g) Amendment to Schedule 7.2 of the Credit Agreement. Schedule 7.2 of
the Credit Agreement is hereby deleted in its entirety and Schedule 7.2 attached
hereto is hereby substituted therefor.





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          (h) Amendment to Section 9.1 of the Credit  Agreement.  Section 9.1 of
the Credit  Agreement is hereby  amended by adding the following new  subsection
(k) thereto:

                    "(k) unsecured Indebtedness owing by MFC to Xomed; provided,
          however,   that  any  such  Indebtedness  shall  be  evidenced  by  an
          intercompany  note which  shall be pledged  to the Agent  pursuant  to
          arrangements in form and substance satisfactory to the Agent."


          (i)  Amendment  to  Section  9.3(h) of the Credit  Agreement.  Section
9.3(h) of the Credit  Agreement  is hereby  amended in its  entirety  to read as
follows:

                    "(h)   Investments  in  wholly-owned   Subsidiaries  of  any
          Borrower;  provided,  that each such Subsidiary  shall have (i) either
          (A) become a borrower  under the Credit  Agreement  and the other Loan
          Documents or (B) guaranteed the prompt payment and  performance of all
          of the  Obligations  pursuant  to a  guaranty  in form  and  substance
          satisfactory  to the  Majority  Banks and (ii) granted to the Agent on
          behalf of the Banks a valid and  perfected  security  interest  in and
          lien on all of the assets and properties of such  Subsidiary  pursuant
          to a security  agreement  in form and  substance  satisfactory  to the
          Majority  Banks;  and provided,  further,  that the  aggregate  Dollar
          amount of all Investments by the Borrowers in all such Subsidiaries by
          the Borrowers shall not exceed $3,000,000 in the aggregate (other than
          Investments permitted under Section 9.3(i))."


          (j) Amendment to Section 9.3 of the Credit  Agreement.  Section 9.3 of
the Credit  Agreement is hereby  amended by adding the following new  subsection
(i) thereto:

                    "(i)  Investments  by  Xomed  in  MFC  as  evidenced  by the
          Indebtedness permitted under Section 9.1(k) hereof."


          (k)  Amendment  to  Section  9.5(b) of the Credit  Agreement.  Section
9.5(b) of the Credit  Agreement is hereby amended by adding the following at the
end of such subsection:

                    "and  other than the sale or  assignment  from time to time,
          subject to the liens and  security  interests  granted in favor of the
          Agent,  by Xomed to MFC or MFC to Xomed  of  Accounts  Receivable  and
          other amounts receivable arising from Xomed's business."


          (l)  Amendment  to Section 9.  Section 9 of the  Credit  Agreement  is
hereby  amended by adding the following as a new Section 9.16 thereto to read as
follows:

                     "Section 9.16. Amendment of Receivable Servicing Agreement.
          Without the prior written consent of the Majority Banks, no Borrower 
          shall cause or permit or consent to any material  amendment or 
          modification  of any term or condition of the Receivable Servicing
          Agreement."





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<PAGE>

          (m) Amendment to Section 20(a) of the Credit Agreement.  Section 20(a)
of the Credit Agreement is hereby amended in its entirety to read as follows:

                    "(a) if to the Borrowers, c/o Xomed Surgical Products, Inc.,
          6743 Southpoint Drive North,  Jacksonville,  Florida 32216, Attention:
          Thomas  Timbie,  or at such other  address for notice as the Borrowers
          shall last have furnished in writing to the Person giving the notice;"


           Section 6. Additional Covenants.  Without any prejudice or impairment
whatsoever to any of the Banks' and/or Agent's rights and remedies  contained in
the Credit Agreement and the covenants  contained therein,  the Revolving Credit
Notes or in any of the other Loan Documents, the Borrowers additionally covenant
and agree with the Banks and Agent as follows:


               (a) The Borrowers shall comply and continue to comply with all of
the terms,  covenants  and  provisions  contained in the Credit  Agreement,  the
Revolving  Credit  Notes and the other  Loan  Documents,  except as such  terms,
covenants and provisions are expressly modified by this Agreement upon the terms
set forth herein.

               (b) The  Borrowers  will not  effect  or cause any  amendment  or
modification  of the  Receivable  Servicing  Agreement in any  material  respect
without the prior written consent of the Majority Banks.


               (c) On or before March 31, 1997,  the Borrowers  shall file their
fiscal year 1995 tax returns and provide evidence of such filing to the Agent.


               (d) The Borrowers  shall at any time or from time to time execute
and deliver such further instruments,  and take such further action as the Agent
and/or Banks may reasonably request, in each case further to effect the purposes
of this  Agreement,  the Credit  Agreement,  the Revolving  Credit Notes and the
other Loan Documents.

           Each of the  Borrowers  expressly  acknowledges  and agrees  that any
failure by any Borrower to comply with the terms and  conditions of this Section
6 or any other provisions  contained in this Agreement shall constitute an Event
of Default under the Credit Agreement.


           Section 7. Expenses.  The Borrowers agree to pay to the Agent and the
Banks upon  demand  (a) an amount  equal to any and all  out-of-pocket  costs or
expenses  (including  reasonable  legal  fees  and  disbursements)  incurred  or
sustained by the Agent and/or Banks in connection  with the  preparation of this
Agreement  and  related   matters  and  (b)  from  time  to  time  any  and  all
out-of-pocket  costs or expenses  (including  commercial examiner fees and legal
fees and  disbursements)  hereafter  incurred or  sustained  by the Agent and/or
Banks in connection with the  administration of credit extended by the Banks and
the Agent to the Borrowers or the  preservation of or enforcement of the Agent's
and the Banks' rights under the Credit Agreement,  the Revolving Credit Notes or
the  other  Loan  Documents  or in  respect  of  any  of  the  Borrowers'  other
obligations to the Banks and/or the Agent.




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<PAGE>


           Section 8. Miscellaneous Provisions.


               (a) Except as otherwise expressly provided by this Agreement, all
of the respective terms, conditions and provisions of the Credit Agreement,  the
Revolving Credit Notes and the other Loan Documents shall remain the same. It is
declared and agreed by each of the parties hereto that the Credit Agreement, the
Revolving  Credit Notes and the other Loan  Documents,  each as amended  hereby,
shall continue in full force and effect,  and that this Agreement and the Credit
Agreement,  the  Revolving  Credit  Notes  and  the  other  Loan  Documents,  as
applicable, shall be read and construed as one instrument.


               (b) This Agreement is intended to take effect under, and shall be
construed according to and governed by, the laws of the State of Connecticut.


               (c) This Agreement may be executed in any number of counterparts,
but all such  counterparts  shall  together  constitute but one  instrument.  In
making  proof of this  Agreement it shall not be necessary to produce or account
for more than one  counterpart  signed by each party hereto by and against which
enforcement hereof is sought.

          IN WITNESS  WHEREOF,  each of the  parties  hereto  have  caused  this
Agreement to be executed in its name and behalf by its duly  authorized  officer
as of the date first written above.

                                        XOMED SURGICAL PRODUCTS, INC.



                                        By: /s/ Thomas E. Timbie
                                             Its Vice President & CFO

                                        MEROCEL CORPORATION



                                        By: /s/ Thomas E. Timbie
                                              Its Treasurer

                                        XOMED, INC.



                                        By: /s/ Thomas E. Timbie
                                              Its Treasurer     
                                            

                                        





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                                        XOMED-TREACE, P.R. INC.



                                        By: /s/ Thomas E. Timbie
                                              Its Treasurer     
                                            
                                        TREBAY MEDICAL CORPORATION



                                         By: /s/ Thomas E. Timbie
                                               Its Treasurer     
                                             
                                         BANK OF BOSTON CONNECTICUT,
                                          Individually and as Agent



                                          By:_____________________________
                                                Garth J. Collins
                                                Its:  Vice President

                                        
                                        
The undersigned  Guarantors  acknowledge                                        
and accept the  foregoing and ratify and                                        
confirm  their  obligations  under their
Unlimited Guaranties:                   


MEROCEL FOREIGN SALES CORP.



By: /s/ Thomas E. Timbie
      Its Treasurer     
    

XOMED INTERNATIONAL, INC.



By: /s/ Thomas E. Timbie
      Its Treasurer     
    



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XOMED CANADA, INC.



By: /s/ Thomas E. Timbie
      Its Treasurer     
    

XOMED AUSTRALIA PTY LIMITED



By: /s/ Thomas E. Timbie
      Its Treasurer     
    

XOMED U.K. LTD.



By: /s/ Thomas E. Timbie
      Its Treasurer     
    

XOMED FRANCE, S.A.



By: /s/ Thomas E. Timbie
      Its Treasurer     
    

XOMED DEUTSCHLAND, GMBH



By: /s/ Thomas E. Timbie
      Its Treasurer     
    



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                                  Schedule 7.2
                                  ------------


                               Ownership Interests