EXHIBIT 10.20

AMENDMENT NO. 6 AND LIMITED WAIVER TO CREDIT AGREEMENT

This AMENDMENT NO. 6 To CREDIT AGREEMENT (this "Amendment"), dated as of April 18, 2008, by and among RADNET MANAGEMENT, INC., a California corporation (the "Borrower"), the other persons designated as Credit Parties on the signature pages hereof, GENERAL ELECTRIC CAPITAL CORPORATION, a Delaware corporation, as agent ("Agent") and the Persons signatory thereto from time to time as Lenders.  Unless otherwise specified herein, capitalized terms used in this Amendment shall have the meanings ascribed to them in the Credit Agreement (each as hereinafter defined).

RECITALS

WHEREAS, the Borrower, the Credit Parties, Agent and Lenders have entered into that certain Credit Agreement dated as of November 15, 2006 (as amended by that certain (i) Limited Waiver and Amendment No. 1 to Credit Agreement dated as of April 5, 2007, (ii) Amendment No. 2 to Credit Agreement dated as of May 30, 2007, (iii) Amendment No. 3 to Credit Agreement dated as of August 23, 2007, (iv) Amendment No. 4 to Credit Agreement dated as of December 3, 2007 and (v) Amendment No. 5 and Limited Waiver to Credit Agreement dated as of February 22, 2008, and as further amended, supplemented, restated or otherwise modified from time to time, the "Credit Agreement''); and

WHEREAS, the Borrowers, Agent and Requisite Lenders have agreed to the amendments as set forth herein;

NOW THEREFORE, in consideration of the mutual execution hereof and other good and valuable consideration, the parties hereto agree as follows:

1.           Amendment to Credit Agreement.

(a)           Amendment to Section 6.2(d).  Section 6.2(d) of the Credit Agreement is hereby amended by replacing the phrase "five (5) Business Days after the end of each Fiscal Month" which appears therein with the phrase "(i) ninety (90) days after the end of each Fiscal Month ending on or about December 31 or January 31, (ii) sixty (60) days after the end of each Fiscal Month ending on or about February 28 and (iii) forty-five (45) days after the end of each other Fiscal Month".

(b)           Amendment to Annex A.  Annex A of the Credit Agreement is hereby amended by deleting the phrase "described in Section 6.2(a)" from the last sentence of the definition of "Borrowing Base".

(c)           Amendment to Exhibit 6.2(d).  Exhibit 6.2(d) of the Credit Agreement is hereby amended by (i) replacing each occurrence of the phrase "[insert date of most recent monthly financial statements required to be delivered pursuant to Section 6.1(a) of Credit Agreement]" with "[insert date of most recent financial statements delivered to Agent]" and (ii) replacing each occurrence of the phrase "Fiscal Quarter" in footnote 2 with the phrase "Fiscal Month".

2.           Limited Waiver.  The Agent and Requisite Lenders hereby waive any breach of Section 6.2(d) of the Credit Agreement which has occurred on or prior to the date hereof, and any Default or Event of Default as a result thereof, to the extent arising solely from the failure of Borrower to deliver a Borrowing Base Certificate within five (5) Business Days after the end of each Fiscal Month.

The waiver set forth above shall be limited precisely as written and shall not be deemed or otherwise construed to constitute a waiver of any other Default or other Event of Default or any other provision the Credit Agreement or any other Loan Document or to prejudice any right, power or remedy which any Agent or any Lender may now have or may have in the future under or in connection with the Credit Agreement or any other Loan Document (after giving effect to this Agreement), all of which rights, powers and remedies are hereby expressly reserved by the Agent and Lenders.

3.           Representations and Warranties of Credit Parties.  The Credit Parties represent and warrant that:

(a)           the execution, delivery and performance by each Credit Party of this Amendment have been duly authorized by all necessary corporate action required on its part and this Amendment is a legal, valid and binding obligation of such Credit Party enforceable against such Credit Party in accordance with its terms except as the enforcement thereof may be subject to (i) the effect of any applicable bankruptcy, insolvency, reorganization, moratorium or similar laws affecting creditors' rights generally and (ii) general principles of equity (regardless of whether enforcement is sought in a proceeding in equity or at law); and

(b)           after giving effect to this Amendment, each of the representations and warranties contained in the Credit Agreement is true and correct in all material respects on and as of the date hereof as if made on the date hereof, except to the extent that such representations and warranties expressly relate to an earlier date.

4.           Conditions To Effectiveness.  This Amendment shall be effective upon satisfaction of the following conditions precedent:

(a)           This Amendment shall have been executed and delivered by the Agent, Requisite Lenders and the Credit Parties; and

(b)           The Agent shall have received, on behalf of each Lender who has executed this Amendment, a nonrefundable amendment fee equal to 0.05% of such Lender's Commitment, which fee shall be fully earned and payable on the date hereof.

5.           Reference To And Effect Upon The Credit Agreement.

(a)           The Credit Agreement and the other Loan Documents shall remain in full force and effect, as amended hereby, and are hereby ratified and confirmed.

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(b)           The execution, delivery and effectiveness of this Amendment shall not operate as a waiver of any right, power or remedy of Agent or any Lender under the Credit Agreement or any Loan Document nor constitute a waiver or amendment of any provision of the Credit Agreement or any Loan Document, except as specifically set forth herein.  Upon the effectiveness of this Amendment, each reference in the Credit Agreement to "this Credit Agreement," "hereunder," "hereof," "herein" or words of similar import shall mean and be a reference to the Credit Agreement as amended hereby.

6.           Governing Law.  THIS AMENDMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF NEW YORK.

7.           Headings.  Section headings in this Amendment are included herein for convenience of reference only and shall not constitute a part of this Amendment for any other purposes.

8.           Counterparts.  This Amendment may be executed in any number of counterparts, each of which when so executed shall be deemed an original, but all such counterparts shall constitute one and the same instrument.

9.           Reaffirmation of Guaranties.  The Credit Parties signatory hereto hereby reaffirm their Guaranties of the Obligations and reaffirm that the Obligations are and continue to be secured by the security interest granted by the Credit Parties in favor of the Agent, on behalf of itself and the Lenders, under the Security Agreement and the Pledge Agreement and all of the terms, conditions, provisions, agreements, requirements, promises, obligations, duties, covenants and representations of the Credit Parties under such documents and agreements entered into with respect to the obligations under the Credit Agreement are incorporated herein by reference and are hereby ratified and affirmed in all respects by the Credit Parties.  Each Credit Party acknowledges that all references to "Credit Agreement" and "Obligations" in the Loan Documents shall take into account the provisions of this Amendment and be a reference to the "Credit Agreement"' and the "Obligations" as amended hereby.

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IN WITNESS WHEREOF, the parties hereto have executed and delivered this Amendment as of the date first written above.

RADNET MANAGEMENT, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

RADNET, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

RADNET MANAGEMENT, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

BEVERLY RADIOLOGY MEDICAL GROUP III
By:	ProNet Imaging Medical Group, Inc., its general partner
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President
By:	Beverly Radiology Medical Group, Inc., its general partner
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President
PRONET IMAGING MEDICAL GROUP, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

Signature Page to Amendment No. 6 to Credit Agreement

BEVERLY RADIOLOGY MEDICAL GROUP, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

RADNET SUB, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

SOCAL MR SITE MANAGEMENT, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

RADNET MANAGEMENT I, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

RADNET MANAGEMENT II, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

Signature Page to Amendment No. 6 to Credit Agreement

RADNET MANAGED IMAGING SERVICES, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

DIAGNOSTIC IMAGING SERVICES, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: Chief Financial Officer

RADIOLOGIX, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

ADVANCED IMAGING PARTNERS, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

IDE IMAGING PARTNERS, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

Signature Page to Amendment No. 6 to Credit Agreement

MID ROCKLAND IMAGING PARTNERS, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

PACIFIC IMAGING PARTNERS, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

QUESTAR IMAGING, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

TREASURE COAST IMAGING PARTNERS, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

COMMUNITY IMAGING PARTNERS, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

Signature Page to Amendment No. 6 to Credit Agreement

RADIOLOGY AND NUCLEAR MEDICINE IMAGING PARTNERS, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

VALLEY IMAGING PARTNERS, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

QUESTAR DULUTH, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

QUESTAR LOS ALAMITOS, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

QUESTAR VICTORVILLE, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

Signature Page to Amendment No. 6 to Credit Agreement

ROCY MOUNTAIN OPENSCAN MRI, LLC
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

FRI, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

FRI II, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

ROLLING OAKS IMAGING CORPORATION
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

ROLLING OAKS RADIOLOGY, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

DELAWARE IMAGING PARTNERS, INC.
By:	/s/ Howard G. Berger
	Name: Howard G. Berger, M.D.
	Title: President

Signature Page to Amendment No. 6 to Credit Agreement

GENERAL ELECTRIC CAPITAL CORPORATION as Agent and a Lender
By:	/s/ Andrew Moore
	Duly Authorized Signatory

Signature Page to Amendment No. 6 to Credit Agreement

Cratos CLO I LTD.
By:	Cratos CDO Management, LLC
	As Attorney-in-fact
By:	Cratos CDO Management, LLC
	As Attorney-in-fact
By:	Cratos Capital Partners, LLC
	Its Manager
By:	/s/ Phyliss Hasen
	Name: Phyliss Hasen Title: Managing Diretor

Signature Page to Amendment No. 6 to Credit Agreement

Cratos CLO II LTD.
By:	Deutsche Bank AG, Cayman Island Branch
	As Attorney-in-fact
By:	John Kim
	Name: John Kim
	Title: Director
By:	/s/ Zhongwei Wu
	Name: Zhongwei Wu Title: Director

Signature Page to Amendment No. 6 to Credit Agreement

ACA CLO 2006-2, Limited, as a Lender
By:	/s/ Vincent Ingato
	Name: Vincent Ingato
	Title: Managing Director

Signature Page to Amendment No. 6 to Credit Agreement

ACA CLO 2007-1, Limited, as a Lender
By:	/s/ Vincent Ingato
	Name: Vincent Ingato
	Title: Managing Director

Signature Page to Amendment No. 6 to Credit Agreement

Greyrock CDO Limited By Aladdin Capital Management, as a Lender
By:	/s/ Giulio Ponte
	Name: Giulio Ponte
	Title: Authorized Signatory

Signature Page to Amendment No. 6 to Credit Agreement

Landmark II CDO Limited By Aladdin Capital Management, as a Lender
By:	/s/ Giulio Ponte
	Name: Giulio Ponte
	Title: Authorized Signatory

Signature Page to Amendment No. 6 to Credit Agreement

 

Landmark IX CDO Limited By Aladdin Capital Management, as a Lender
By:	/s/ Giulio Ponte
	Name: Giulio Ponte
	Title: Authorized Signatory

Signature Page to Amendment No. 6 to Credit Agreement

  

Landmark VI CDO Limited By Aladdin Capital Management, as a Lender
By:	/s/ Giulio Ponte
	Name: Giulio Ponte
	Title: Authorized Signatory

Signature Page to Amendment No. 6 to Credit Agreement

Landmark VII CDO Limited By Aladdin Capital Management, as a Lender
By:	/s/ Giulio Ponte
	Name: Giulio Ponte

Signature Page to Amendment No. 6 to Credit Agreement

BLACK DIAMOND CLO 2006-1 (CAYMAN)Ltd. By: Black Diamond CLO 2006-1 Advisor, LLC., As its Collateral Manager
By:	/s/ Stephen H. Deckoff
	Name: Stephen H. Deckoff
	Title: Managing Principal

Signature Page to Amendment No. 6 to Credit Agreement

BLACK DIAMOND CLO 2005-2 Ltd. By: Black Diamond CLO 2005-2 Advisor, LLC., As its Collateral Manager
By:	/s/ Stephen H. Deckoff
	Name: Stephen H. Deckoff
	Title: Managing Principal

Signature Page to Amendment No. 6 to Credit Agreement

DIAMOND SPRINGS TRADING LLC, as a Lender
By:	/s/ Tara E. Kennedy
	Name: Tara E. Kennedy
	Title: Assistance Vice President

Signature Page to Amendment No. 6 to Credit Agreement

CIFC Funding 2006-I, Ltd CIFC Funding 2006-IB, Ltd. CIFC Funding 2006-II, Ltd. CIFC Funding 2007-I, Ltd. CIFC Funding 2007-II, Ltd., as Lender
By:	/s/ Elizabeth C. Chow
	Name: Elizabeth C. Chow
	Title: Head of Underwriting

Signature Page to Amendment No. 6 to Credit Agreement

PREMIER FUNDING, LTD., as a Lender
By: Citigroup Global Markets Realty Corp., as Collateral Administrator
By:	/s/ Authorized Signatory
	Title: Authorized Signatory

Signature Page to Amendment No. 6 to Credit Agreement

ColumbusNova CLO Ltd. 2006-II as Lender
By:	/s/ Paul L. Cal
	Name: Paul L. Cal
	Title: Associate Director

ColumbusNova CLO Ltd. 2007-I as Lender
By:	/s/ Paul L. Cal
	Name: Paul L. Cal
	Title: Associate Director

ColumbusNova CLO IV Ltd. 2007-II as Lender
By:	/s/ Paul L. Cal
	Name: Paul L. Cal
	Title: Associate Director

Signature Page to Amendment No. 6 to Credit Agreement

NAVIGATOR CDO 2005, LTD., as a Lender
By: GE Asset Management Inc., as Collateral Manager
By:	/s/ Kathleen Brooks
	Name: Kathleen Brooks
	Title: Authorized Signatory

NAVIGATOR CDO 2006, LTD., as a Lender
By: GE Asset Management Inc., as Collateral Manager
By:	/s/ Kathleen Brooks
	Name: Kathleen Brooks
	Title: Authorized Signatory

Signature Page to Amendment No. 6 to Credit Agreement

SANDELMAN FINANCE 2006-2, LTD., as a Lender
By: Sandelman Partners, LP as Collateral Manager
By:	/s/ Lou Terlizzi
	Name: Lou Terlizzi
	Title: Authorized Signatory

SANDELMAN FINANCE 2006-1, LTD., as a Lender
By: Sandelman Partners, LP as Collateral Manager
By:	/s/ Lou Terlizzi
	Name: Lou Terlizzi
	Title: Authorized Signatory

Signature Page to Amendment No. 6 to Credit Agreement

ROYAL BANK OF CANADA, as a Lender
By:	/s/ Gordon MacArthur
	Name: Gordon MacArthur
	Title: Authorized Signatory

Signature Page to Amendment No. 6 to Credit Agreement

Pangaea Asset Management, LLC, as Collateral Agent of CLO 2007-1 LTD
Pangaea CLO 2007-1 LTD. by Pangaea Asset Management, LLC, its CollateralManager as a Lender
By:	/s/ Matthew Nels
	Name: Matthew Nels
	Title: Assistant Secretary

Signature Page to Amendment No. 6 to Credit Agreement

Grand Central Asset Trust, BDC, Series, as a Lender
By:	/s/ Brian Schott
	Name: Brian Schott
	Title: Attorney-in-fact

Signature Page to Amendment No. 6 to Credit Agreement

SENIOR DEBT PORTFOLIO, as a Lender
By: Boston Management and Research as Investment Advisor
By:	/s/ Michael B. Botthof
	Name: Michael B. Botthof
	Title: Vice President

Signature Page to Amendment No. 6 to Credit Agreement

EATON VANCE SENIOR INCOME TRUST, as a Lender
By: Eaton Vance Management as Investment Advisor
By:	/s/ Michael B. Botthof
	Name: Michael B. Botthof
	Title: Vice President

Signature Page to Amendment No. 6 to Credit Agreement

EATON VANCE INSTITUTIONAL SENIOR LOAN FUND, as a Lender
By: Eaton Vance Management as Investment Advisor
By:	/s/ Michael B. Botthof
	Name: Michael B. Botthof
	Title: Vice President

Signature Page to Amendment No. 6 to Credit Agreement

EATON VANCE CDO VII PLC, as a Lender
By: Eaton Vance Management as Investment Advisor
By:	/s/ Michael B. Botthof
	Name: Michael B. Botthof
	Title: Vice President

Signature Page to Amendment No. 6 to Credit Agreement

EATON VANCE CDO VIII Ltd., as a Lender
By: Eaton Vance Management as Investment Advisor
By:	/s/ Michael B. Botthof
	Name: Michael B. Botthof
	Title: Vice President

Signature Page to Amendment No. 6 to Credit Agreement

EATON VANCE CDO X PLC, as a Lender
By: Eaton Vance Management as Investment Advisor
By:	/s/ Michael B. Botthof
	Name: Michael B. Botthof
	Title: Vice President

Signature Page to Amendment No. 6 to Credit Agreement

GRAYSON & CO., as a Lender
By: Boston Management and Research as Investment Advisor
By:	/s/ Michael B. Botthof
	Name: Michael B. Botthof
	Title: Vice President

Signature Page to Amendment No. 6 to Credit Agreement

  

EATON VANCE, as a Lender LIMITED DURATION INCOME FUND
By: Eaton Vance Management as Investment Advisor
By:	/s/ Michael B. Botthof
	Name: Michael B. Botthof
	Title: Vice President

Signature Page to Amendment No. 6 to Credit Agreement

   

EATON VANCE SENIOR FLOATING-RATE TRUST, as a Lender
By: Eaton Vance Management as Investment Advisor
By:	/s/ Michael B. Botthof
	Name: Michael B. Botthof
	Title: Vice President

Signature Page to Amendment No. 6 to Credit Agreement

   

EATON VANCE FLOATING-RATE INCOME TRUST, as a Lender
By: Eaton Vance Management as Investment Advisor
By:	/s/ Michael B. Botthof
	Name: Michael B. Botthof
	Title: Vice President

Signature Page to Amendment No. 6 to Credit Agreement

   

EATON VANCE VARIABLE LEVERAGE FUND Ltd., as a Lender
By: Eaton Vance Management as Investment Advisor
By:	/s/ Michael B. Botthof
	Name: Michael B. Botthof
	Title: Vice President

Signature Page to Amendment No. 6 to Credit Agreement

   

MC Funding Ltd., as a Lender
By: Monroe Capital Management, LLC As Collateral Manager
By:	/s/ Jeremy VanDermaid
	Name: Jeremy VanDermaid
	Title: Senior Vice President

Signature Page to Amendment No. 6 to Credit Agreement

   

ORIX FINANCE CORP., as a Lender
By:	/s/ Christopher L. Smith
	Name: Christopher L. Smith
	Title: Authorized Representative

Signature Page to Amendment No. 6 to Credit Agreement

   

Satellite Senior Income Fund II, as a Lender
By: Satellite Asset Management, LP. Its Investment Manager
By:	/s/ Simon Raykher
	Name: Simon Raykher
	Title: General Counsel

Signature Page to Amendment No. 6 to Credit Agreement

   

TELOS CLO 2006-1, LTD TELOS CLO 2007-2, LTD
By:	/s/ Jonathan Tepper
	Name: Jonathan Tepper
	Title: Principal

Signature Page to Amendment No. 6 to Credit Agreement

   

CoLTS 2005-2, LTD.,  as a Lender
by: Structured Asset Investors, LLC       as Collateral Manager
By:	/s/ Kevin McCarthy
	Name: Kevin McCarthy
	Title: Managing Director

Signature Page to Amendment No. 6 to Credit Agreement

   

CoLTS 2007-1, LTD.,  as a Lender
by: Structured Asset Investors, LLC       as Collateral Manager
By:	/s/ Kevin McCarthy
	Name: Kevin McCarthy
	Title: Managing Director

Signature Page to Amendment No. 6 to Credit Agreement

   

Grand Central Asset Trust, DES Series, as a Lender
By:	/s/ Roy Hykal
	Name: Roy Hykal
	Title: Attorney-in-fact

   
Signature Page to Amendment No. 6 to Credit Agreement

   

Clear Lake CLO, Ltd., as a Lender
By:	/s/ Jeremy Johnson
	Name: Jeremy Johnson
	Title: Assistant Vice President

Signature Page to Amendment No. 6 to Credit Agreement

   

Diamond Lake CLO, Ltd., as a Lender
By:	/s/ Jeremy Johnson
	Name: Jeremy Johnson
	Title: Assistant Vice President

Signature Page to Amendment No. 6 to Credit Agreement

   

St. James River CLO, Ltd., as a Lender
By:	/s/ Jeremy Johnson
	Name: Jeremy Johnson
	Title: Assistant Vice President

Signature Page to Amendment No. 6 to Credit Agreement

   

Summit Lake CLO, Ltd., as a Lender
By:	/s/ Jeremy Johnson
	Name: Jeremy Johnson
	Title: Assistant Vice President

Signature Page to Amendment No. 6 to Credit Agreement

   

Victoria Falls CLO, Ltd., as a Lender
By:	/s/ Jeremy Johnson
	Name: Jeremy Johnson
	Title: Assistant Vice President

Signature Page to Amendment No. 6 to Credit Agreement

   

Merrill Lynch CLO 2007 -1 Ltd. by 250 Capital LLC, its Collateral Manager as a Lender
By:	/s/ Kelli O’Connell
	Name: Kelli O’Connell
	Title: Managing Director

Signature Page to Amendment No. 6 to Credit Agreement