EXHIBIT 10.57

                       THIRD AMENDMENT TO LOAN DOCUMENTS

     This Third Amendment to Loan Documents (this "Amendment") is made and
entered into as of this 31st day of December, 2009, by and among Intraop Medical
Corporation, a Nevada corporation (the "Company"), and the investors of the
Company set forth on the signature pages hereto (the "Investors").   Capitalized
terms used but not defined herein shall have the meanings assigned thereto in
the Loan Documents (as defined below).

                                    RECITALS

     Whereas, pursuant to that certain Debenture Purchase Agreement, dated as of
September 30, 2008 and amended as of April 9, 2009 and June 30, 2009 (the
"Purchase Agreement"), the Company has issued to the Investors 10% Senior
Secured Debentures (as the same may have been amended and restated, the
"Debentures");

     Whereas, to secure the Company's obligations under the Debentures, the
Company and the Investors have entered into a Security Agreement, dated as of
September 30, 2008 and amended as of April 9, 2009 and June 30, 2009 (the
"Security Agreement" and, together with the Purchase Agreement and the
Debentures, the "Loan Documents"); and

     Whereas, the Company and the Investors wish to amend certain terms of the
Loan Documents as described below.

                                   AGREEMENT

     Now, Therefore, in consideration of these premises and for other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto agree as follows:

1.   Amendment.

     1.1     Amendment  to  Loan  Documents.

        (a) The  Debentures  that are outstanding on the date hereof are hereby
amended  by  changing  the  references  to "December 31, 2009" in (i) the second
paragraph  of  the  preamble thereto and (ii) the definition of "Monthly Payment
Date"  in  Section  1  thereof  to  "January  31,  2010".

        (b) The  Purchase  Agreement  is hereby amended such that the
form  of  the  Debenture  attached  thereto  as Exhibit A is consistent with the
amendments  to  the  Debentures  set  forth  in  Section  1.1(a).

        (c) The  Purchase  Agreement  is  hereby  amended  by changing the
reference to "December 31, 2009" in the first sentence of Section 2.4 thereof to
"January  31,  2010".

     1.2     Effect  on  Agreements.

        (a)  Except as expressly set forth in Section 1.1 of this Amendment, the
Loan  Documents  shall be and remain in full force and effect in accordance with
their  terms.  The  Loan Documents, as amended by Section 1.1 of this Amendment,
are  hereby  ratified  and  confirmed  in  all  respects.

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        (b)  Nothing contained herein shall in any way impair the Debentures now
held  for  the Obligations, nor affect or impair any rights, powers, or remedies
under  the  Loan  Documents, it being the intent of the parties hereto that this
Amendment  shall  not  constitute  a novation of the Debentures or an accord and
satisfaction  of  the Obligations. The Company hereby ratifies and reaffirms the
validity  and  enforceability  of  all  of  the  liens  and  security  interests
heretofore  granted  pursuant  to the Loan Documents, as collateral security for
the Obligations, and acknowledges that all of such liens and security interests,
and all Collateral heretofore pledged as security for the Obligations, continues
to be and remains Collateral for the Obligations from and after the date hereof.

2.     Miscellaneous.

     2.1     Governing  Law.  This  Amendment shall be governed by and construed
under the internal laws of the State of Delaware in all respects, without giving
effect  to  conflict  of  law  principles  thereof.

     2.2  Entire  Agreement.  This  Amendment  and the other documents delivered
pursuant  hereto  constitute  the  full  and  entire understanding and agreement
between  the  parties  with  regard  to  the  subjects  hereof.

     2.3  Severability.  In  the  event  one  or  more of the provisions of this
Amendment  should,  for  any  reason,  be  held  to  be  invalid,  illegal  or
unenforceable  in  any  respect, such invalidity, illegality or unenforceability
shall  not  affect  any  other  provisions of this Amendment, and this Amendment
shall  be  construed  as if such invalid, illegal or unenforceable provision had
never  been  contained  herein.

     2.4  Titles  and  Subtitles.  The titles of the sections and subsections of
this  Amendment  are  for  convenience  of  reference  only  and  are  not to be
considered  in  construing  this  Amendment.

     2.5  Counterparts.  This  Amendment  may  be  executed  in  any  number  of
counterparts,  each  of  which  shall  be an original, but all of which together
shall  constitute  one  instrument.

                     [THIS SPACE INTENTIONALLY LEFT BLANK]

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     In  Witness  Whereof, the undersigned have caused this Amendment to be duly
executed  as  of  the  day  and  year  first  written  above.

                                            COMPANY:
                                            INTRAOP MEDICAL CORPORATION

                                            By: /s/ John Powers
                                                --------------------------------
                                                Name: John Powers
                                                Title: Chief Executive Officer

                                            INVESTORS:

                                            E.U. CAPITAL VENTURE, INC.

                                            By: /s/ Hans Morker
                                                --------------------------------
                                                Name: Hans Morker
                                                Title: Managing Director

                                            ENCYCLOPEDIA EQUIPMENT LLC

                                            By: /s/ Oliver Janssen
                                                --------------------------------
                                                Name: Oliver Janssen
                                                Title: Member

                                            VMG HOLDINGS II, LLC

                                            By: /s/ Gregory S. Koonsman
                                                --------------------------------
                                                Name: Gregory S. Koonsman
                                                Title: Managing Partner

<PAGE>

                                            LACUNA VENTURE FUND LLLP

                                              By: Lacuna Hedge GP LLLP, its
                                                  general partner


                                              By: Lacuna, LLC, its general
                                                  partner

                                            By: /s/ Rawleigh Ralls
                                                --------------------------------
                                                Name: Rawleigh Ralls
                                                Title: Managing Director

                                            LACUNA HEDGE FUND LLLP

                                              By: Lacuna Hedge GP LLLP, its
                                                  general partner

                                              By: Lacuna, LLC, its general
                                                  partner

                                            By: /s/ Rawleigh Ralls
                                                --------------------------------
                                                Name: Rawleigh Ralls
                                                Title: Managing Director





                                            /s/ Rawleigh Ralls
                                          --------------------------------------
                                            RAWLEIGH RALLS