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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0000885725-05-000128.txt : 20050425
<SEC-HEADER>0000885725-05-000128.hdr.sgml : 20050425
<ACCEPTANCE-DATETIME>20050425103313
ACCESSION NUMBER:		0000885725-05-000128
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050422
FILED AS OF DATE:		20050425
DATE AS OF CHANGE:		20050425

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ASPECT MEDICAL SYSTEMS INC
		CENTRAL INDEX KEY:			0000886235
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTROMEDICAL & ELECTROTHERAPEUTIC APPARATUS [3845]
		IRS NUMBER:				954154357
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		141 NEEDHAM STREET
		CITY:			NEWTON
		STATE:			MA
		ZIP:			02464-1505
		BUSINESS PHONE:		(617) 559-7857

	MAIL ADDRESS:	
		STREET 1:		141 NEWTON STREET
		CITY:			NEWTON
		STATE:			MA
		ZIP:			02464-1505

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BOSTON SCIENTIFIC CORP
		CENTRAL INDEX KEY:			0000885725
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-24663
		FILM NUMBER:		05768980

	BUSINESS ADDRESS:	
		STREET 1:		ONE BOSTON SCIENTIFIC PL
		CITY:			NATICK
		STATE:			MA
		ZIP:			01760-1537
		BUSINESS PHONE:		5086508000
</SEC-HEADER>
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<SEQUENCE>1
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            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>017601537</rptOwnerZipCode>
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    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>By: /s/Lawrence J. Knopf,Vice President</signatureName>
        <signatureDate>2005-04-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----