UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of the earliest event reported):  September 6, 2006

PRIMEDEX HEALTH SYSTEMS, INC.

(Exact Name of Registrant as Specified in Its Charter)

1510 Cotner Avenue
Los Angeles, California 90025

(Address of Principal Executive Offices) (Zip Code)

(310) 478-7808

(Registrant’s Telephone Number, Including Area Code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

x    Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o    Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o    Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o    Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 8.01            Other Events

Primedex Health Systems, Inc. (“Primedex”) announced today that the U.S. Federal Trade Commission, on August 22, 2006, granted early termination of the waiting period imposed by the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, in connection with Primedex’s proposed acquisition of Radiologix, Inc.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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