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                                                                    Exhibit 4.3

                              EMPLOYMENT AGREEMENT

         THIS AGREEMENT made as of the 4th day of February, 1998 BETWEEN:

         IMI International Medical Innovations Inc., a corporation incorporated
         under the laws of Canada

         (hereinafter called "IMI")

                                       and

         Mr. Ron Hosking, of the City of Toronto, in the Province of Ontario
         (hereinafter called

         the "Employee").


         WHEREAS IMI and the Employee wish to enter into a written agreement
which contains the agreed upon terms and conditions of employment for their
mutual benefit;

         NOW THEREFORE in consideration of the mutual covenants and agreements
contained in this agreement and for other good and valuable consideration, the
adequacy of which is hereby acknowledged, the parties to this agreement do
mutually covenant and agree as follows:

ARTICLE 1 - DUTIES OF EMPLOYMENT

1.1   Position - The Company agrees to continue to employ the Employee in the
position of Vice-President Finance and Chief Financial Officer, to serve in such
capacity as IMI's needs may, from time to time, require and as are made known to
him by IMI or its authorized representatives. In this capacity, the Employee
shall perform such services as are required from time to time by the President
and Board of Directors of IMI (the Board) provided, however, that without the
Employees prior written consent, the Employee shall not be required to perform
services other than those comparable in scope and dignity to those the Employee
is presently performing.

1.2   Duties - The Employee accepts the office on the terms and conditions set
forth in this Agreement and acknowledges that as Vice-President Finance and
Chief Financial Officer, he has the responsibility for the general financial
management of the business of IMI, subject to the authority of the President and
Board. Throughout the term of his employment, the Employee agrees to devote
substantially all of his business time and effort to carry out the performance
of his duties under this Agreement and shall conform to all lawful instructions
and directions given to him by the President and Board, or its authorized
designees, and obey and carry out the by-laws of IMI, as well as all written
rules, policies and practices now or hereafter established and amended from time
to time by IMI for the conduct of its affairs and brought to the attention of
the Employee.

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ARTICLE II - AUTHORITY

2.1   The Employee shall have, subject always to the general or specific
instructions and directions of the President and Board, or its authorized
designees, including, without limitation, subject to the provisions and
limitations of any budget approved by the Board, full power and authority to
manage and direct the business and affairs of IMI consistent with the Employee's
position as set out in Section 1.1.

ARTICLE III - TERMS OF EMPLOYMENT

3.1   Term - The provisions of the Agreement shall have effect from the date
hereof and shall continue in effect until January 12, 1999, or until terminated
in accordance with the provisions of this Agreement. Subject to the provisions
of this Agreement, thereafter, this Agreement shall be automatically renewed for
successive one-year periods if no written notice has been given by either party
to the other on or before 60 days before the end of the term stating such
party's intention to terminate this Agreement.

ARTICLE IV - EMPLOYEE'S COMPENSATION AND BENEFITS

4.1   Compensation - The annual base salary payable to the Employee for the
Employees services hereunder for the term of this Agreement shall be $100,000
(gross), exclusive of bonuses, benefits and other compensation. The annual base
salary payable to the Employee pursuant to the provisions of this Article IV
shall be payable in equal monthly installments, in arrears, in accordance with
existing practice, or in such other manner as may be mutually agreed upon, less,
in any case, any deductions or withholdings required by law.

4.2   Salary Review - The Employee's salary and benefits shall be as stated in
Article IV but shall be reviewed on October 31, 1998 and annually thereafter
during the term of this Agreement and any renewal of this Agreement.

4.3   Vacation - The Employee shall be entitled to vacation with pay of four (4)
weeks during each calendar year of this Agreement. Vacation not taken in one
year may not be carried over into subsequent years and shall expire at the end
of the applicable year unless agreed upon in advance by the President.

4.4   Benefits - The Employee shall participate in all benefit plans which IMI
provides to its Employees, including extended health, medical and dental. In the
event that such benefit plans include additional benefits and/or coverage for
executives, then the Employee shall be entitled to such additional benefits.

4.5   Additional Compensation - The Employee shall also receive bonuses and
options to purchase shares of IMI as may be granted by the Board, in their
discretion, from time to time.

4.6   Expenses - IMI shall reimburse the Employee forthwith for all proper and
reasonable out-of-pocket expenses actually incurred by the Employee in the
performance of his duties upon presentation of supporting statements, receipts
or vouchers. Subject to the provisions of IMI s

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governing corporate legislation, IMI agrees to indemnify and save the Employee
harmless from and against any and all demands, claims, costs, charges and
expenses, including an amount paid to settle an action or satisfy a judgment,
reasonably incurred by him in respect of any civil, criminal or administrative
action or proceeding to which the Employee is made a party by reason of having
been a director or officer of IMI or of any affiliated company, whether before
or after termination if:

      (a)   the Employee acted honestly and in good faith with a view to the
            best interests of IMI; and

      (b)   in the case of a criminal or administrative action or proceeding
            that is enforced by a monetary penalty, the Employee had
            reasonable grounds for believing that his conduct was lawful.

ARTICLE V - TERMINATION

5.1   Notwithstanding anything contained in this Agreement, IMI and the Employee
agree that this Agreement and the employment of the Employee may be terminated
as follows:

(a)   immediately by IMI at its option, at any time, and without notice or pay
in lieu of such notice, for cause. For the purposes of this Agreement, cause
shall include the following:

      (i)   a material breach by the Employee of the provisions of Article VI
      at any time;

      (ii)  conviction of the Employee of a criminal offense punishable by
      indictment, or summary conviction where such cause is not prohibited by
      the law and where such conviction brings into question the Employee's
      ability to perform his duties under this Agreement honestly and
      effectively or where such conviction could adversely affect the
      reputation and goodwill of IMI; and

      (iii) in the event of death or any disability , as such term is defined
      in any disability insurance policy of IMI or if no such policy is in
      place, disability shall mean mental or physical disability or serious
      illness of the Employee which results in the Employee being unable to
      substantially perform his duties for a continuous period of 180 days or
      for periods aggregating 225 days in any period of 365 days;

(b)   at any time by IMI, without cause by paying, in lieu of notice, an amount
      equal to 6 months of the Employee's current annual salary, payable in a
      lump sum; or

(c)   at any time by the Employee upon 60 days written notice to IMI.

5.2   Effect of Termination

(a)   Upon termination of this Agreement, the employment of the Employee shall
be automatically terminated and the Employee shall have no claims against IMI
for failure to give

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reasonable notice of termination or otherwise except in respect of payment of
salary or accrued vacation pay to the date of termination and payments
specifically provided for herein.

(b)   Upon termination of employment, the Employee shall immediately resign all
offices (including directorships) held in IMI and the Employee shall not be
entitled to receive any additional severance pay or compensation for loss of
office or otherwise by reason of resignation (other than as otherwise provided
for herein). If the Employee fails to resign as mentioned, IMI is irrevocably
authorized to appoint some person in the Employee's name and on his behalf to
sign any documents or do any thing necessary or requisite to give effect to it.

(c)   If the Employee is terminated without cause, all options, which were
originally granted at market price, to acquire shares of IMI held by the
Employee shall immediately and automatically become fully vested and shall be
exercisable by the Employee within the time period which is thirty (30) days
from the date of such termination and, after such 30 day period, all unexercised
options held by the Employee shall expire and shall be canceled by IMI.

(d)   if the Employee is terminated with cause, all options, whether vested or
otherwise, shall immediately expire and shall be canceled at the date of such
termination.

(e)   The provisions of subsections (c) and (d) above shall apply to all options
to acquire shares of IMI granted previously or hereafter to the Employee unless
the terms of such options specifically state that such subsections do not apply.

5.3   Company's Property

The Employee acknowledges that all items of any and every nature or kind created
or used by the Employee pursuant to the Employee's employment under this
Agreement, or furnished by IMI to the Employee, and all equipment, credit cards,
books, records, reports, files, manuals, literature, confidential information or
other materials shall remain and be considered the exclusive property of IMI at
all times and shall be surrendered to IMI, in good condition, promptly on the
termination of the Employee's employment irrespective of the time, manner or
cause of termination. All personal effects used by the Employee in carrying out
his duties will remain the property of the Employee and shall be removed by him
on termination of his employment.

ARTICLE VI - CONFIDENTIAL INFORMATION AND NON-COMPETITION

6.1   Confidential Information

(a)   The Employee acknowledges that throughout the course of his employment
with IMI the Employee may have access to and be entrusted with confidential
information, trade secrets and know-how concerning the business and property of
IMI and with information, trade secrets and know-how which other persons shall
require IMI and its employees, agents and consultants to treat as confidential
(all of which information, trade secrets and know-how of IMI and others shall be
collectively defined as Confidential Information).

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(b)   The Employee agrees that disclosure of any of the Confidential Information
or any use of the Confidential Information other than on behalf of or for the
direct benefit of IMI is and will be highly detrimental to IMI and that the
right to maintain the confidentiality of the Confidential Information
constitutes a proprietary right which IMI is entitled to protect or is an
obligation which IMI must observe. Accordingly, the Employee hereby agrees that:

      (i)   he shall keep confidential all of the Confidential Information for
      the exclusive benefit and use of IMI and will faithfully do all in his
      power to assist IMI in keeping the Confidential Information confidential
      until IMI shall make the same public either by obtaining patent rights,
      copyrights or otherwise;

      (ii)  he shall not, directly or indirectly, disclose or divulge any of the
      Confidential Information to any person, firm, corporation or other entity
      of any kind whatsoever;

      (iii) he shall not, directly or indirectly, either individually or in
      partnership with, or jointly with one or more persons, firms, corporations
      or any other entity of any kind whatsoever as principal, agent, employee,
      shareholder or in any other capacity or manner whatsoever, use any of the
      Confidential Information other than on behalf of or for the direct benefit
      of IMI;

      (iv)  he shall not divulge, disclose or communicate to any person, firm or
      corporation the name of any customer of IMI and/or the Business (as
      hereinafter defined); and

      (v)   he shall not use for his own purpose any Confidential Information
      relating to IMI and/or the Business.

(c)   The Employee acknowledges that the restrictions contained herein for the
benefit of IMI are reasonable and not excessive in the circumstances of the
Employee's knowledge and the scope of his employment.

6.2   Non-Competition - The Employee agrees that the Employee will not, without
the prior written consent of IMI, while employed by IMI and for a period of one
(1) year after the date of termination for cause:

(a)   directly or indirectly, in any manner whatsoever, including, without
limitation, either individually or in partnership or jointly, or in conjunction
with any other person or persons, firm, association, syndicate, company or
corporation, as principal, agent, shareholder or in any other manner whatsoever,
carry on or be engaged in any business similar to or competitive with the
business of IMI (the Business) in any country where IMI operates, or be
concerned with or interested in or lend money to, guarantee the debts or
obligations of or permit his name or any part thereof to be used or employed by
any person, persons, firm, association, syndicate, company or corporation
engaged in, concerned with or interested in any competitive business except that
the Employee may own no more than 5% of the total issued and outstanding capital
stock of a publicly-held or private corporation engaged in, concerned with or
interested in any competitive business;

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(b)   directly or indirectly solicit, interfere with or endeavor to direct or
entice away from IMI any customer or any person, firm or corporation in the
habit of dealing with IMI, and/or the Business; or

(c)   interfere with, entice away or otherwise attempt to obtain the withdrawal
of any employee or independent contractor of IMI or, following termination of
the Employee s employment, any employee who was in the employ of IMI during the
one (1) year period, as the case may be, preceding termination for cause.

6.3   The Employee hereby acknowledges and agrees that all covenants, provisions
and restrictions contained in this Article VI hereof are reasonable and valid
and all defenses to the strict enforcement thereof by IMI are waived by the
Employee.

6.4   The Employee further acknowledges and agrees that in the event of a
violation of the covenants, provisions and restrictions contained in this
Article VI, IMI shall be authorized and entitled to obtain from any court of
competent jurisdiction preliminary and permanent injunctive relief and an
accounting of all profits and benefits arising out of such violation, which
rights and remedies shall be cumulative and in addition to any other rights or
remedies to which IMI may be entitled.

6.5   It is understood by the Parties hereto that the covenants in this Article
VI by the Employee not to enter into competition with IMI are essential elements
to this Agreement and that, but for the agreement of the Employee to enter into
such covenants, IMI would not have retained the Employee.

ARTICLE VII - CLAUSES SURVIVING TERMINATION

7.1   Any confidentiality and non-solicitation clauses in Article VI of this
Agreement shall survive the termination of this Agreement, as shall Sections 4.6
and 5.2 hereof.

ARTICLE VIII - PLAIN ENGLISH

8.1   This Agreement is intended to be written in plain English. When words or
expressions of a general nature are employed herein, it is intended that they be
comprehensive, unless the context clearly dictates otherwise.

ARTICLE IX - GENERAL

9.1   General - Any notice, document or other communication required or
permitted to be given in respect of this Agreement shall be sufficiently given
if delivered to the party personally, or if sent by prepaid ordinary mail posted
in Canada, by courier, or faxed, to such party addressed as follows:

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IMI:        IMI International Medical Innovations Inc.
            5955 Airport Road
            Suite 222
            Mississauga, Ontario L4V lR9
            Telecopier No: (905) 677-4912
            Attention:  President

Employee:   Ron Hosking
            30 Hatherton Crescent
            Don Mills, Ontario

            M3A 1P7

Any party may at any time change its address hereunder by giving notice of such
change of address to the other party or parties in the manner specified in this
paragraph. Any such notice or other written communication shall, if mailed or
sent by courier, be effective on the day it is delivered or an attempt is made
to deliver it to the address of the addressee and, if -given by personal
delivery, shall be effective on the day of actual delivery.

9.2   Severability - If any covenant, provision or restriction contained in this
Agreement is found to be void or unenforceable in whole or in part, it shall not
affect or impair the validity of any other covenant, provision or restriction
and without limitation, each of the covenants, provisions and restrictions
contained herein are hereby declared to be separate and distinct covenants,
provisions and restrictions.

9.3   Waiver of Performance - The Employee and IMI may, in writing, extend the
time for performance or waive non-compliance or non-performance by the other of
the others obligations, covenants and agreements under this Agreement. No act or
failure to act of the Employee or IMI shall be deemed to be an extension or
waiver of timely or strict performance by the other of his/its obligations,
covenants and agreements under this Agreement.

9.4   Governing Law - This Agreement shall be governed by and construed in
accordance with the laws of the Province of Ontario and the law of Canada
applicable therein and each of the parties hereby irrevocably attorn to the
jurisdiction of the courts of the Province of Ontario.

9.5   Entire Agreement - This Agreement set forth the entire agreement among the
parties hereto pertaining to the employment of the Employee and supersedes all
prior agreements, understanding, negotiations and discussions, whether oral or
written, of the parties hereto, and there are no warranties, representations or
other agreements between the parties hereto in connection with the subject
matter hereof except as specifically set forth therein. No supplement,
modification, waiver or termination of this Agreement shall be binding unless
executed in writing by the parties to be bound thereby.

9.6   Assignment - This Agreement is personal to the Employee and may not be
assigned by him without the prior written consent of IMI, which consent may be
unreasonably withheld. This Agreement may not be assigned by IMI without the
prior written consent of the Employee, which consent may be unreasonably
withheld. Subject to the foregoing, this Agreement shall

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ensure to the benefit of and be binding upon the Parties and their respective
successors, heirs, executors, administrators, personal representatives and
permitted assigns.

9.7   Headings - The headings used in this Agreement are for convenience only
      and are not to be construed in any way as additions to or limitations of
      the covenants and agreements contained herein.

9.8   Currency - All dollar amounts referred to in this Agreement shall be in
Canadian funds.

9.9   Time of Essence - Time is and shall always remain the essence of this
Agreement.

      IN WITNESS WHEREOF the parties hereto have executed this Agreement on the
day and year first above written.

                                      IMI International Medical Innovations Inc.

                                      Per /s/ Brent Norton              c/s
                                         ----------------------------


SIGNED, SEALED AND DELIVERED        )
         In the presence of:        )
                                    )
Witness /s/ Anderson                )         /s/ Ron Hosking
        -------------------------             --------------------------
                                    )         Ron Hosking


By signing, the Employee acknowledges he understands the contents of this
Agreement, and in particular Article V relating to termination and that he has
been given the opportunity to obtain independent legal advice and has either
done so or chosen not to obtain such advice.