EXHIBIT 5.1
                                                September 25, 1998


The Board of Directors
InSight Health Services Corp.
4400 MacArthur Boulevard, Suite 800
Newport Beach, California  92660

Ladies and Gentlemen:

         We have acted as special counsel to InSight Health Services Corp., a
Delaware corporation (the "Company"), and each of the wholly-owned subsidiaries
set forth in Schedule A hereto (the "Subsidiary Guarantors"), in connection with
the public offering by the Company of $100,000,000 aggregate principal amount of
its 9 5/8% Series B Senior Subordinated Notes due 2008 (the "Exchange Notes"),
which will be guaranteed, on a senior subordinated basis pursuant to the
guarantees (the "Subsidiary Guarantees") by the Subsidiary Guarantors. The
Exchange Notes are to be issued pursuant to an exchange offer (the "Exchange
Offer") in exchange for a like principal amount of the issued and outstanding
9 5/8% Senior Subordinated Notes due 2008 of the Company (the "Outstanding
Notes") under an Indenture, dated as of June 1, 1998 (the "Indenture"), between
the Company, the Subsidiary Guarantors and State Street Bank and Trust Company,
N.A., as trustee (the "Trustee"), as contemplated by the Registration Rights
Agreement dated June 12, 1998 (the "Registration Rights Agreement") by and among
the Company, the Subsidiary Guarantors and NationsBanc Montgomery Securities
LLC, Morgan Stanley & Co. Incorporated and Sutro & Co. Incorporated.

         This opinion is being furnished in accordance with the requirements of
Item 601(b)(5) of Regulation S-K under the Securities Act of 1933, as amended
(the "Securities Act").

         In connection with this opinion, we have examined originals or copies,
certified or otherwise identified to our satisfaction, of (i) the Registration
Statement on Form S-4 (File No. 333-60573) as filed with the Securities and
Exchange Commission (the "Commission") on August 4, 1998, as amended, under the
Securities Act, the "Registration Statement"); (ii) the Registration Rights
Agreement; (iii) the Indenture; (iv) the Form T-1 of the Trustee filed as an
exhibit to the Registration Statement; and (v) the form of Exchange Note,
including the form of Subsidiary Guarantee. We have also examined originals or
copies, certified or otherwise identified to our satisfaction, of such records
of the Company and the Subsidiary Guarantors and such agreements, certificates
of officers or other representatives of the Company and the Subsidiary
Guarantors and





others, and such other documents, certificates and records as we have deemed
necessary or appropriate as a basis for the opinions set forth herein. In
rendering the opinions set forth below, we do not express any opinion as to the
applicability or effect of any fraudulent transfer or similar law.

         In our examination, we have assumed the legal capacity of all natural
persons, the genuineness of all signatures, the authenticity of all documents
submitted to us as originals, the conformity to original documents of all
documents submitted to us as certified or photostatic copies and the
authenticity of the originals of such latter documents. In making our
examination of documents, we have assumed that all parties executing such
documents had the power, corporate or other, to enter into and perform all
obligations thereunder and have also assumed the due authorization by all
requisite action, corporate or other, and execution and delivery by such parties
of such documents (except for the execution and delivery of the Indenture, the
Exchange Notes and the Subsidiary Guarantees by the Company and the Subsidiary
Guarantors, as applicable, insofar as execution and delivery are matters
governed by New York law) and the validity and binding effect thereof (except,
insofar as the Company and the Subsidiary Guarantors are concerned, for the
Indenture, the Exchange Notes and the Subsidiary Guarantees, in each case to the
extent specifically addressed and subject to the qualifications stated herein).
As to any facts material to the opinions expressed herein which we have not
independently established or verified, we have relied upon oral or written
statements and representations of officers or other representatives of the
Company, the Subsidiary Guarantors and others.

         We have also assumed that the issuance and sale of the Exchange Notes
by the Company and the issuance of the Subsidiary Guarantees by the Subsidiary
Guarantors and the execution and delivery of the Indenture, the Notes and the
Subsidiary Guarantees and the performance of the respective obligations of the
Company and of the Subsidiary Guarantors thereunder, and the consummation of the
transactions contemplated thereby, do not and will not conflict with,
contravene, violate or constitute a default under (i) any leases, indenture,
instrument or other agreement to which the Company or the Subsidiary Guarantors
is subject, (ii) any rule, law or regulation to which the Company or the
Subsidiary Guarantors is subject, (iii) any judicial or administrative order or
decree of any governmental authority to which the Company or the Subsidiary
Guarantors is subject, or (iv) any consent, approval, license, authorization or
validation of, or filing, recording or registration with, any governmental
authority.

         Members of our firm are admitted to the bar in the State of New York.
The opinions expressed in this letter concern only the effect of the laws
(excluding the

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principles of conflicts of laws) of the State of New York, the General
Corporation Law of the State of Delaware and federal law as currently in effect,
and we do not express any opinion as to the laws of any other jurisdiction. We
assume no obligation to supplement this letter if any of the applicable laws
change in any manner.

         Based upon and subject to the foregoing and the limitations,
qualifications, exceptions and assumptions set forth herein, we are of the
opinion that when (i) the Registration Statement becomes effective and the
Indenture has been qualified under the Trust Indenture Act of 1938, as amended
(the "Trust Indenture Act"), and (ii) the Exchange Notes have been duly executed
and authenticated in accordance with the terms of the Indenture and have been
delivered upon consummation of the Exchange Offer against receipt of Outstanding
Notes surrendered in exchange therefor in accordance with the terms of the
Exchange Offer, the Exchange Notes and Subsidiary Guarantees will be validly
issued and will constitute valid and binding obligations of the Company and the
Subsidiary Guarantors, respectively, except to the extent that the validity and
binding nature thereof may be limited by bankruptcy, insolvency, reorganization,
moratorium, fraudulent conveyance or transfer, preferential transfers or
distributions by corporations to shareholders or other laws now or hereafter in
effect relating to rights of creditors or other obligees generally.

         We hereby consent to the filing of this opinion with the Commission as
an exhibit to the Registration Statement. We also consent to the reference to
our firm under the captions "Legal Matters" in the Registration Statement. In
giving this consent, we do not thereby admit that we are included in the
category of persons whose consent is required under Section 7 of the Act or the
rules and regulations of the Commission. The opinions expressed in this letter
are limited to the matters set forth in this letter, and no other opinions
should be inferred beyond the matters expressly stated.

                                         Very truly yours,

                                         /s/
                                         ARENT FOX KINTNER PLOTKIN & KAHN, PLLC

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