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                                                                   EXHIBIT 10.10

[MICRUS COMPANY LOGO]

                               OFFER OF EMPLOYMENT

This letter dated May 23, 2003, represents a formal offer of at-will employment
at Micrus Corporation. Micrus wishes to extend this offer to EDWARD RUPPEL for
the position of Director of Technical Operations with a proposed start date of
June 2, 2003. Employment will not begin until the terms in this offer are agreed
to and acknowledged by signature of this letter. This offer is valid through May
27, 2003.

ELIGIBILITY

On your first day of work, please bring with you evidence of your U.S.
citizenship or proof of your legal right to live and work in this country. We
are required by federal law to examine documentation of your employment
eligibility within three business days after you begin work.

In addition, your employment at Micrus is contingent upon your execution and
compliance with several Company Agreements as follows: Employment Agreement,
Confidentiality and Proprietary Information Agreements, and an Arbitration
Agreement. In addition, the Invention Assignment Agreement must be signed thus
requiring, among other provisions, the assignment of patent rights to any
invention made during your employment at the Company to Micrus Corporation.

COMPENSATION

Upon commencement of employment, EDWARD RUPPEL will be paid $6346.15 bi-weekly
in accordance with the Company's normal payroll procedures. We have recommended
that EDWARD RUPPEL receive stock options in the amount of 8000 shares. These
options are subject to the Board of Directors' approval and the exercise price
for the options will be equal to the fair market value of the Company's common
stock on the grant date. One-fourth of the options vest at the end of the first
year of employment, and one-forty-eighth vest each full month thereafter. These
options would not preclude the award of additional options that may carry a
different exercise price and/or vesting period. The option grant shall be
subject to the terms, definitions and provisions of the Company's 1998 Stock
Plan and Stock Option Agreement by and between you and the Company, both of
which documents are incorporated herein by reference. In the event that
employment is terminated for any reason, all rights to exercise unvested stock
options will be cancelled as per the applicable ISO Stock Options Plan.

BENEFITS

The following benefits will be made available to Edward Ruppel upon commencement
of employment under the same terms as other Micrus employees and in accordance
with the Company's Benefits Program.

-     Health, Dental, Vision, and Disability/Life Insurance

-     401(k)

-     Holiday pay

-     PTO pay (Paid Time Off-to be accrued and used in accordance with Company
      policy)

By accepting the Micrus Corporation Offer of Employment, you will be
acknowledging and expressly agreeing that at all times you will be an at-will
employee. Thus, you and Micrus Corporation will retain the right to terminate
the employment relationship for any reason. Upon any termination of the
employment relationship, Micrus Corporation's only liability to you will be for
payment of salary and vacation time earned prior to the termination date. The
at-will nature of this employment relationship can be modified or nullified only
in a formal written employment contract signed by you and the President of
Micrus Corporation. This letter, along with any agreements relating to
proprietary rights between you and the Company, set forth the terms of your
employment with the Company and supersede any prior representations or
agreements.

Agreed to and accepted by:

/s/ MICHEL MOUNIER        5/13/03               /s/ EDWARD RUPPEL   5/27/03
-----------------------------------             --------------------------------
Michel Mounier             Date                 Edward Ruppel         Date
CEO Micrus Corporation