EXHIBIT 10.51



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                       NON-DISTURBANCE, SUBORDINATION AND
                              ATTORNMENT AGREEMENT


THIS NON-DISTURBANCE, SUBORDINATION AND ATTORNMENT AGREEMENT (this "Agreement")
dated October 22, 1996 is by and among PENNSYLVANIA INDUSTRIAL DEVELOPMENT
AUTHORITY ("PIDA"), SLT PROPERTIES, INC., a Delaware corporation ("Owner"),
SURGICAL LASER TECHNOLOGIES, INC., a Delaware corporation ("Sublandlord") and
SUBURBAN CABLE TV CO. INC., a Pennsylvania corporation ("Subtenant").

BACKGROUND

A.   PIDA is the holder of a mortgage ("Mortgage") dated August 16, 1991 and
     recorded in the public records of Montgomery County, Pennsylvania, granted
     by the Owner and by Montgomery County Industrial Development Corporation to
     PIDA, in the original principal amount of $2,000,000, which Mortgage
     creates a mortgage lien on premises commonly known as 200 Cresson
     Boulevard, Oaks, Pennsylvania ("Premises").

B.   Owner and Sublandlord entered into a Lease Agreement dated August 16, 1991
     ("Lease") pursuant to which Owner leased the Premises to Sublandlord.

C.   Sublandlord and Subtenant have entered into a Sublease Agreement dated
     March 21, 1996 ("Sublease"), pursuant to which Sublandlord has agreed to
     sublease the Premises to Subtenant. The Sublease provides that Subtenant
     has the right to terminate the Sublease if PIDA does not execute this
     Agreement.

D.   By the execution of this Agreement, the parties wish to provide for the
     nondisturbance of Subtenant's possession of the Premises and the
     subordination of the Subtenant's leasehold estate to the lien of the
     Mortgage.

NOW, THEREFORE, for good and valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, and intending to be legally bound, the parties
agree as follows:

1.   Subtenant hereby acknowledges and agrees that its leasehold estate created
     under the terms of the Sublease and all of its rights thereunder will be
     subject and subordinate to the rights and lien of PIDA under the terms of
     the Mortgage and any modifications, replacements, renewals or extensions
     thereof.

2.   So long as Subtenant is not in default in performing its obligations under
     the terms of the Sublease, PIDA agrees, for itself and its successors and
     assigns, that it will not disturb or interfere with the enjoyment by
     Subtenant of Subtenant's leasehold estate in the Premises, including all
     rights granted by the Sublease. However, in no event shall PIDA, or any
     subsequent purchaser or grantee; (a) be liable for any act or omission or
     Owner or Sublandlord; (b) be subject to any offset or deficiency which
     Subtenant may have against Owner or Sublandlord; or (c) have any obligation
     with respect to any security deposited under the Sublease unless such
     security has been delivered to PIDA.

3.   If PIDA succeeds to the Owner's interest as landlord, either as a result of
     mortgage foreclosure proceedings or as a result of any conveyance in lieu
     of mortgage foreclosure, and Sublandlord ceases to be entitled to
     possession under the Lease, then Subtenant agrees that it will attorn
     directly to PIDA (or in the event of a foreclosure or sale of the Premises
     to any purchaser or grantee) as if PIDA were the landlord named in the
     Sublease; PIDA, in turn, will accept the Subtenant's attornment and will
     recognize the leasehold interest of Subtenant under the terms of the
     Sublease, to the end that Subtenant may continue to

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     peaceably and quietly have, hold and enjoy the Premises, provided that
     Subtenant has then complied and continues to comply with the terms of
     the Sublease.

4.   Subtenant acknowledges that it has notice that the Lease and the Sublease
     and the rent and all sums due thereunder have been assigned to the PIDA as
     part of the security for the note secured by the Mortgage. If PIDA notifies
     Subtenant of a default under the Mortgage or note, and demands that
     Subtenant pay its rent and all other sums due under the Sublease to PIDA,
     Subtenant agrees that it will honor such demand and pay its rent and all
     other sums due under the Sublease, directly to PIDA.

5.   Subtenant covenants and acknowledges that except to the extent provided in
     the Sublease, it has no right or option of any nature whatsoever, whether
     pursuant to the Sublease or otherwise, to purchase the Premises or any
     portion thereof, or any interest in the Premises. To the extent that
     Subtenant has any such right or option, the same is hereby acknowledged to
     be subject to and subordinate to the Mortgage. PIDA shall have no
     obligation, nor incur any liability, with respect to any warranties of any
     nature whatsoever, whether pursuant to the Sublease or otherwise including,
     without limitation, any warranties respecting use, compliance with zoning,
     habitability, fitness for purpose or possession.

6.   Anything herein or in the Sublease to the contrary notwithstanding, if PIDA
     shall acquire title to the Premises, PIDA shall have no obligation, nor
     incur any liability, beyond PIDA's then interest, if any, in the Premises
     for the payment and discharge of any obligations imposed upon PIDA
     hereunder or under the Sublease, and PIDA is hereby released or relieved of
     any other obligations hereunder and under the Sublease. Provided that funds
     have been paid directly to PIDA in return for PIDA's promise to use such
     fund for a specific purpose and provided further that PIDA has failed to
     use funds for such specific purpose, Subtenant agrees that with respect to
     any money judgment against PIDA, Subtenant will look solely to the estate
     or interest owned by PIDA in the Premises or any portion thereof, and
     Subtenant will not collect or attempt to collect any such judgment out of
     any other assets of PIDA. Subtenant acknowledges that it has not paid any
     money directly to PIDA as of the date of this Agreement for any purpose
     other than payment of lease payments as required under the Lease.

7.   Subtenant will neither offer nor make prepayment of rent (for a period in
     excess of one month) nor further change the terms, covenants, conditions
     and agreements of the Sublease in any manner without the express consent in
     writing of PIDA, which consent shall not be unreasonably withheld.

8.   The foregoing provisions shall be self-operative and effective without the
     execution of any further instrument of any party hereto. However, Subtenant
     agrees to execute and deliver to PIDA or to any person to whom Subtenant
     herein agrees to attorn, such other instruments as either shall reasonably
     request, in order to effectuate the foregoing provisions.

9.   No modification, amendment, waiver or release of any provision of this
     Agreement shall be valid or binding unless in writing and duly executed by
     the party against whom the same is sought to be asserted.

10.  This Agreement shall be binding upon and inure to the benefit of the
     parties hereto and their respective successors and assigns. Provided,
     however, that in the event of the assignment or transfer of the interest of
     the lender, all obligations and liabilities of PIDA under this Agreement
     shall terminate and all such obligations and liabilities shall be the
     responsibility of the party to whom PIDA's interest is assigned or
     transferred; and provided further that the interest of Subtenant under this
     Agreement may not be assigned or transferred without the written consent of
     PIDA.

11.  This Agreement shall be construed in accordance with the laws of the
     Commonwealth of Pennsylvania.

12.  This Agreement may be executed in multiple counterparts, all of which,
     taken together, shall constitute an original.


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IN WITNESS WHEREOF, the parties have executed and delivered this Agreement as of
the date first above written.

PENNSYLVANIA INDUSTRIAL DEVELOPMENT
AUTHORITY




By:   /s/ Marguerite Harris, Administrator
      -----------------------------------

ATTEST OR WITNESS:    /s/ Evelyn Shepley, Assistant Secretary
                      ---------------------------------------

SLT PROPERTIES, INC.

By:   /s/ Michael R. Stewart, V.P.
      ----------------------------

ATTEST OR WITNESS:    /s/ Davis Woodward, Secretary
                      -----------------------------

SURGICAL LASER TECHNOLOGIES, INC.

By:   /s/ Michael R. Stewart, V.P.
      ----------------------------

ATTEST OR WITNESS:    /s/ Davis Woodward, Secretary
                      -----------------------------

SUBURBAN CABLE TV CO.  INC.

By:   /s/ Robert Lawrence, Executive V.P.
      ----------------------------

ATTEST OR WITNESS:   /s/ Henry F. Brooks, V.P.
                     ------------------------------




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