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AMENDING AGREEMENT

THIS AMENDING AGREEMENT is made as of the 1st day of September, 2005 between
OCCULOGIX, INC. (the “Company”), a corporation incorporated under the laws of
the State of Delaware, and Irving J. Siegel, who resides in the Town of Richmond
Hill in the Province of Ontario (hereinafter referred to as the “Employee”).

WHEREAS the Vascular Sciences Corporation (now the Company) and the Employee
entered into an employment agreement, dated as of August 1, 2003, setting forth
the rights and obligations of each of them with respect to the Employee’s
employment with Vascular Sciences Corporation (now the Company) (the “Employment
Agreement”);

AND WHEREAS Quest Clinical Trials Inc. (now AMD Medical Services Inc.), of which
the Employee is a beneficial owner, director and officer, Rheo Clinic Inc. and
OccuLogix, L.P., both of which are affiliates of the Company, and the Employee
entered into an amended and restated consulting agreement (the “Consulting
Agreement”), dated as of August 1, 2003, pursuant to which, among other things,
Quest Clinical Trials Inc. (now AMD Medical Services Inc.) provided medical and
other services to Rheo Clinic Inc. in connection with the operation of its
Rheopheresis™ clinic located in the City of Mississauga (the “Rheo Clinic”);

AND WHEREAS now the Company effectively operates the Rheo Clinic, and the nature
of its practice has changed in such a manner so as to make it appropriate to
adjust the scope and nature of the services that were being provided by AMD
Medical Services Inc. pursuant to the Consulting Agreement;

AND WHEREAS the Company, AMD Medical Services Inc. and the Employee, as of the
date hereof, will enter into a consulting agreement, that is intended to replace
the Consulting Agreement, which will reflect the adjusted scope and nature of
the services to be provided by AMD Medical Services Inc. to the Company in
connection with its operation of the Rheo Clinic and in connection with other
clinical trial-related activities of the Company;

NOW, THEREFORE, in consideration of the mutual covenants and undertakings
contained in the Employment Agreement, as amended by this Amending Agreement,
and other good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, the Company and the Employee agree as follows:

1.
Section 5 of the Employment Agreement is hereby deleted in its entirety and
replaced with the following provision:

5. Duties. The Employee is engaged to serve as Vice President, Clinical Affairs
of the Company and shall have such other duties as, from time to time, may be
reasonably assigned to him by the Board of Directors of the Company. During the
term hereof, the Employee shall devote the necessary time, energy and attention
required to fulfill his duties and responsibilities hereunder. Nothing herein
shall preclude the Employee from being involved, directly or indirectly, with
any other business or profession as long as his involvement in such other
business or profession, in the opinion of the Company, does not interfere or
conflict with the execution of his duties hereunder.

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2.
Section 6(a) of the Employment Agreement is hereby deleted in its entirety and
replaced with the following provision:

(a) The Company shall pay to the Employee, as compensation for all services
rendered by the Employee hereunder, an annual base salary of CDN$225,000,
subject to such deductions as may be agreed upon by the parties or required by
law. The Board of Directors of the Company, or the Compensation Committee
thereof, shall review the Employee’s performance and base salary on an annual
basis and may provide for such increase, if any, in the base salary as it may
determine appropriate. This salary shall be paid in accordance with the
Company’s customary payroll procedure.

3.
Section 6(d) of the Employment Agreement is hereby deleted in its entirety and
replaced with the following provision:

(d) Subject to achieving objectives determined on an annual basis by the Board
of Directors of the Company (the “Bonus Criteria”), the Employee shall be
entitled to an annual bonus of up to a maximum of 33⅓% of the Employee’s annual
base salary, which bonus shall be calculated based on the formula set out in the
Bonus Criteria.

4.
The Employee’s annual bonus entitlement for 2005 shall be determined, in whole,
in accordance with Section 6(d) of the Employment Agreement, as it is amended by
this Amending Agreement, and, accordingly, shall be an amount equal to the
applicable percentage (of up to a maximum of 33⅓%) of CDN$225,000, being the
Employee’s annual base salary.

5.
Section 7(c)(ii) of the Employment Agreement is hereby deleted in its entirety
and replaced with the following provision:

(ii) severance pay equal to: (A) 24 months’ salary hereunder if such termination
occurs after July 31, 2005 but before August 1, 2008; and (B) 32 months’ salary
hereunder if such termination occurs after July 31, 2008; in each case, payable
in either equal monthly installments or in a lump sum payment at the discretion
of the Employee;

6.
Section 7(d) of the Employment Agreement is hereby deleted in its entirety and
replaced with the following provision:

(d) Adjustment to Payment upon Termination. If pursuant to Section 6(a) hereof,
the Employee’s base salary is increased, the Board of Directors of the Company,
or the Compensation Committee thereof, in its complete discretion, may reduce
the number of months’ salary payable pursuant to Section 7(c)(ii), provided,
however, that, at no time, shall the amount of severance pay payable pursuant to
Section 7(c)(ii) be less than the amount of severance that would have been
payable based on an annual base salary of CDN$225,000.

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7.
The Employment Agreement remains in full force and effect, unamended, other than
as amended by this Amending Agreement.

8.
This Amending Agreement may be signed by facsimile and in counterpart, and each
such counterpart will constitute an original document, and such counterparts,
taken together, will constitute one and the same instrument.

9.
This Amending Agreement shall be governed by, and construed in accordance with,
the laws of the Province of Ontario and the laws of Canada applicable therein.

10.
The Employee acknowledges that:

 
(a)
he has had sufficient time to review and consider this Amending Agreement
thoroughly;

 
(b)
he has read and understands the terms of this Amending Agreement and his
obligations under the Employment Agreement, as amended by this Amending
Agreement;

 
(c)
he has been given an opportunity to obtain independent legal advice, and such
other advice as he may desire, concerning the interpretation and effect of this
Amending Agreement; and

 
(d)
this Amending Agreement is entered into voluntarily and without any pressure and
that his continued employment with the Corporation has not been made conditional
on execution and delivery by him of this Amending Agreement.

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

             
Signature of Witness
 
Irving J. Siegel
           
Name of Witness (please print)
         
OCCULOGIX, INC.
 
 
By:
     
Thomas P. Reeves
   
President and Chief Operating Officer
     

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