EXHIBIT 99.1
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                               CONTINUATION SHEET

Explanation of Responses:
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(1)  Pursuant to a Contribution and Exchange Agreement (the "Contribution
     Agreement"), dated April 4, 2005, by and among Micro Therapeutics, Inc.
     (the "Company"), ev3 LLC, a Delaware limited liability company ("ev3 LLC"),
     ev3 Inc., a Delaware corporation and wholly owned subsidiary of ev3 LLC
     ("ev3 Inc."), Warburg, Pincus Equity Partners, L.P., a Delaware limited
     partnership (together with three affiliated entities, "WPEP"), Vertical
     Fund I, L.P., a Delaware limited partnership, and Vertical Fund II, L.P., a
     Delaware limited partnership (together with Vertical Fund I, L.P., the
     "Vertical Funds", and together with WPEP, the "Contributors"), the
     Contributors have agreed, upon the terms and subject to the conditions set
     forth in the Contribution Agreement, to contribute (the "Contribution") to
     ev3 LLC an aggregate of 9,704,819 shares of the Company's common stock, par
     value $0.001 per share (the "Common Stock"), comprised of a contribution of
     7,593,384 shares by WPEP and 2,111,435 shares by the Vertical Funds. The
     Contribution Agreement was entered into in connection with certain
     reorganization transactions relating to the proposed initial public
     offering of common stock, par value $0.01 per share, of ev3 Inc. (the
     "IPO"). Subject to the terms and conditions set forth in the Contribution
     Agreement, the Contribution will take place within two business days of the
     date on which a registration statement containing the range of estimated
     IPO prices and the ratio of reverse stock split contemplated in connection
     with the IPO is first filed by ev3 Inc. with the Securities and Exchange
     Commission. Upon the closing of the Contribution, each Contributor will
     receive a number of common membership units of ev3 LLC determined by a
     formula set forth in the Contribution Agreement. As a result of the
     execution of the Contribution Agreement, WPEP may be deemed to have
     acquired beneficial ownership of the 2,111,435 shares of the Common Stock
     to be contributed to ev3 LLC by the Vertical Funds.

(2)  The sole general partner of WPEP is Warburg Pincus Partners LLC, a New York
     limited liability company ("WPP LLC"). WPP LLC is managed by Warburg Pincus
     & Co., a New York general partnership ("WP"). Warburg Pincus LLC, a New
     York limited liability company ("WP LLC"), manages WPEP. The reporting
     person, a director of the Company, is a managing director and member of WP
     LLC and a general partner of WP. By reason of the provisions of Rule 16a-1
     of the Securities Exchange Act of 1934, as amended, the reporting person
     may be deemed to be the beneficial owner of an indeterminate portion of the
     24,336,759 shares of the Common Stock owned by Micro Investment, LLC, a
     Delaware limited liability company ("Micro LLC"), which is indirectly
     controlled by WPEP, and an indeterminate portion of the 9,704,819 shares of
     the Common Stock that will be owned by ev3 LLC, which is indirectly
     controlled by WPEP, upon the closing of the transactions contemplated by
     the Contribution Agreement. The reporting person disclaims beneficial
     ownership of all shares of Common Stock owned by Micro LLC and all shares
     of Common Stock to be owned by ev3 LLC, in each case, except to the extent
     of any indirect pecuniary interest therein.