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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON D.C. 20549

                                   FORM 10-K/A

              ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE
                        SECURITIES EXCHANGE ACT OF 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2007

                         COMMISSION FILE NUMBER 0-19019

                                  RADNET, INC.
               (EXACT NAME OF REGISTRANT AS SPECIFIED IN CHARTER)

              NEW YORK                                  13-3326724
  (STATE OR OTHER JURISDICTION OF                    (I.R.S. EMPLOYER
   INCORPORATION OR ORGANIZATION)                    IDENTIFICATION NO.)

            1510 COTNER AVENUE
          LOS ANGELES, CALIFORNIA                          90025
 (ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)                (ZIP CODE)

       REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE: (310) 478-7808
           SECURITIES REGISTERED PURSUANT TO SECTION 12(B) OF THE ACT:
                         COMMON STOCK, $.0001 PAR VALUE
           SECURITIES REGISTERED PURSUANT TO SECTION 12(G) OF THE ACT:
                         COMMON STOCK, $.0001 PAR VALUE

Indicate by check mark if the registrant is a well-known seasoned issuer, as
defined in Rule 405 of the Securities Act. Yes [ ] No [X]

Indicate by check mark if the registrant is not required to file reports
pursuant to Section 13 or Section 15(d) or the act. Yes [ ] No [X]

      NOTE--Checking the box above will not relieve any registrant required to
file reports pursuant to section 13 or (15(d) of the exchange Act from their
obligations under those Sections.

Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities and Exchange Act of 1934
during the preceding 12 months (or for such shorter period that the registrant
was required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. Yes [X] No [ ]

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. [X]

Indicate by check mark whether the registrant is a large accelerated filer, an
accelerated filer, a non-accelerated filer, or a smaller reporting company. See
the definitions of "large accelerated filer," "accelerated filer" and "smaller
reporting company" in Rule 12b-2 of the Exchange Act.

     Large Accelerated Filer  [ ]
     Accelerated Filer  [X]
     Non-Accelerated Filer  [ ] (Do not check if a smaller reporting company)
     Smaller Reporting Company  [ ]

Indicate by check mark whether the registrant is a shell company (as defined in
Exchange Act Rule 12b-2) Yes [ ] No [X]

The aggregate market value of the registrant's voting and nonvoting common
equity held by non-affiliates of the registrant was approximately $190,029,896
on June 30, 2007 (the last business day of the registrant's most recently
completed second quarter) based on the closing price for the common stock on the
NASDAQ Global Market on June 30, 2007.

Indicate by check mark whether the registrant has filed all documents and
reports required to be filed by Section 12, 13 or 15(d) of the Securities
Exchange Act of 1934 subsequent to the distribution of securities under a plan
confirmed by a court. Yes [X] No [ ]

The number of shares of the registrant's common stock outstanding on March 31,
2008, was 35,639,558 shares (excluding treasury shares).

                       DOCUMENTS INCORPORATED BY REFERENCE

Portions of the following documents are herein incorporated by reference into
the Part of the Form 10-K indicated.

    Document                                              Where Incorporated
    --------                                              ------------------
    Proxy Statement for the 2008 Annual
    Meeting of Shareholders                               Part III

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EXPLANATORY NOTE:

This Amendment No. 1 to Form 10-K for the year ended December 31, 2007, is filed
to include Exhibit 10.39. This exhibit was inadvertently not included in the
original filing of the Annual Report on Form 10-K. This Amendment No. 1 does not
amend any other information and the Company has not updated disclosures
contained therein to reflect any events that occurred at a date subsequent to
the date the Form 10-K was originally filed.

<TABLE>
<CAPTION>
<S>                                                                           <C>
                                                                                                INCORPORATED BY
EXHIBIT NO.                                DESCRIPTION OF EXHIBIT                                REFERENCE TO
-----------                                ----------------------                                ------------

10.20            Master Amendment Agreement with General Electric Capital Corporation,                (K)
                 General Electric Company and GE Healthcare Financial Services

10.21            Amended, Restated and Consolidated Loan and Security Agreement with DVI              (K)
                 Financial Services, Inc.

10.22            Amendment to Loan Documents re US Bank Portfolio Services                            (K)

10.23            Credit Agreement with Wells Fargo Foothill, Inc.                                     (K)

10.24            Employment Agreement with Mark Stolper dated July 30, 2004*                          (N)

10.25            Second Amended and Restated Loan and Security Agreement with Post Advisory           (L)
                 Group, LLC

10.26            Amended, Restated and Consolidated Loan and Security Agreement with Post             (L)
                 Advisory Group, LLC

10.27            Fourth Amendment to Credit Agreement Substituting Bridge Healthcare                  (M)
                 Finance, LLC for Wells Fargo Foothill, Inc.

10.28            2006 Incentive Stock Plan*                                                           (O)

10.29            Credit Agreement, dated as November 15, 2006, among Radnet Management,               (P)
                 Inc., the Credit Parties designated therein, General Electric Capital
                 Corporation, as Agent, the lenders described therein, and GE Capital
                 Markets, Inc.

10.30            Guaranty, dated as of November 15, 2006, by and among the Guarantors                 (P)
                 identified therein and General Electric Capital Corporation.

10.31            Pledge Agreement, dated as of November 15, 2006, by and among the Pledgors           (P)
                 identified therein and General Electric Capital Corporation.

10.32            Security Agreement, dated as of November 15, 2006, by and among the                  (P)
                 Grantors identified therein and General Electric Capital Corporation.

10.33            Second Lien Credit Agreement, dated as of November 15, 2006, among Radnet            (P)
                 Management, Inc., the Credit Parties designated therein, General Electric
                 Capital Corporation, as Agent, the Lenders described therein, and GE
                 Capital Markets, Inc.

10.34            Second Lien Guaranty, dated as of November 15, 2006, by and among the                (P)
                 Guarantors identified therein and General Electric Capital Corporation.

10.35            Pledge Agreement, dated as of November 15, 2006, by and among the Pledgors           (P)
                 identified therein and General Electric Capital Corporation.

10.36            Second Lien Security Agreement, dated as of November 15, 2006, by and                (P)
                 among the Grantors identified therein and General Electric Capital
                 Corporation.

10.37            Retention Agreement with Stephen Forthuber dated November 15, 2006.                  (S)

10.38            Amendment of Existing Credit Agreement with General Electric Capital                 (T)
                 Corporation dated November 2007.

10.39            Amendment of Existing Credit Agreement with General Electric Capital                 (V)
                 Corporation dated February 2008.

<PAGE>

                                                                                                INCORPORATED BY
EXHIBIT NO.                                DESCRIPTION OF EXHIBIT                                REFERENCE TO
-----------                                ----------------------                                ------------
14               Code of Financial Ethics                                                             (H)

21               List of Subsidiaries                                                                 (V)

23.1             Consent of Registered Independent Public Accounting Firm                             (V)

31.1             CEO Certification pursuant to Section 302                                            (V)

31.2             CFO Certification pursuant to Section 302                                            (V)

32.1             CEO Certification pursuant to Section 906                                            (V)

32.2             CFO Certification pursuant to Section 906                                            (V)
</TABLE>

-------------
*     Management contract with compensatory arrangement.

(A)   Incorporated by reference to exhibit filed with Registrant's Registration
      Statement on Form S-1 File No. 33-51870.

(AA)  Incorporated by reference to exhibit filed with Registrant's Registration
      Statement on Form S-3 File 33-73150.

(B)   Incorporated by reference to exhibit filed with Registrant's Registration
      Statement on Form T-3 File No. 022-28703.

(C)   Incorporated by reference to exhibit filed in an amendment to Form 8-K
      report for June 12, 1992.

(D)   Incorporated by reference to exhibit filed with Form 10-K for the year
      ended October 31, 1996.

(E)   Incorporated by reference to exhibit filed with the Form 10-K for the year
      ended October 31, 2000.

(F)   Incorporated by reference to exhibit filed with the Form 10-Q for the
      quarter ended January 31, 2000.

(G)   Incorporated by reference to exhibit filed with the Form 10-K for the year
      ended October 31, 2001.

(H)   Incorporated by reference to exhibit filed with the Form 10-K for the year
      ended October 31, 2003.

(I)   Incorporated by reference to exhibit filed with the Form 10-Q for the
      quarter ended January 31, 2004.

(J)   Incorporated by reference to exhibit filed with the Form 10-Q for the
      quarter ended April 30, 2004.

(K)   Incorporated by reference to exhibit filed with the Form 8-K report for
      August 2, 2004.

(L)   Incorporated by reference to exhibit filed with Form 8-K for November 29,
      2004.

(M)   Incorporated by reference to exhibit filed with Form 8-K for September 14,
      2005.

(N)   Incorporated by reference to exhibit filed with Form 10-K for October 31,
      2004.

(O)   Incorporated by reference to exhibit filed with Registrant's Registration
      Statement on Form S-4 (File No. 333-136800).

(P)   Incorporated by reference to exhibit filed with Form 8-K for November 15,
      2006.

(Q)   Incorporated by reference to exhibit filed with Form 8-K for November 27,
      2006.

(R)   Incorporated by reference to exhibit filed with Form 10-K for October 31,
      2006.

(S)   Incorporated by reference to exhibit filed with Form 10-K/T for December
      31, 2006.

(T)   Incorporated by reference to exhibit filed with Form 8-K for August 24,
      2007.

(U)   Incorporated by reference to exhibit filed with Form 8-K for November 30,
      2007.

(V)   Filed herewith.

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                                   SIGNATURES

      Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the Registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized.

                                        RADNET, INC.

Date: April 1, 2008                     /s/ Howard G. Berger, M.D.
                                        ------------------------------------
                                        HOWARD G. BERGER, M.D., PRESIDENT,
                                        CHIEF EXECUTIVE OFFICER AND DIRECTOR

Pursuant to the requirements of the Securities Exchange Act of 1934, this report
has been signed below by the following persons on behalf of the Registrant and
in the capacities and on the dates indicated:

By     /s/ HOWARD G. BERGER, M.D.
   ---------------------------------------
   HOWARD G. BERGER, M.D., DIRECTOR, CHIEF
   EXECUTIVE OFFICER AND PRESIDENT

Date:  April 1, 2008

By     /s/ MARVIN S. CADWELL
   ---------------------------------------
   MARVIN S. CADWELL, DIRECTOR

Date:  April 1, 2008

By     /s/ JOHN V. CRUES, III, M.D.
   ---------------------------------------
   JOHN V. CRUES, III, M.D., DIRECTOR

Date:  April 1, 2008

By     /s/ NORMAN R. HAMES
   ---------------------------------------
   NORMAN R. HAMES, DIRECTOR

Date:  April 1, 2008

By     /s/ DAVID L. SWARTZ
   ---------------------------------------
   DAVID L. SWARTZ, DIRECTOR

Date:  April 1, 2008

By     /s/ LAWRENCE L. LEVITT
   ---------------------------------------
   LAWRENCE L. LEVITT, DIRECTOR

Date:  April 1, 2008

By     /s/ MICHAEL L. SHERMAN, M.D.
   ---------------------------------------
   MICHAEL L. SHERMAN, M.D., DIRECTOR

Date:   April 1, 2008

By     /s/ MARK D. STOLPER
   ---------------------------------------
   MARK D. STOLPER, CHIEF FINANCIAL OFFICER
   (Principal Accounting Officer)

Date:  April 1, 2008