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                                                                    EXHIBIT 10.3

                     AMENDED AND RESTATED GUARANTY AGREEMENT

To:   Healthcare Business Credit Corporation                Date: March 22, 2005
      305 Fellowship Road, Suite 300
      Mt. Laurel, NJ 08054

      To induce you to establish and/or continue financing arrangements with and
consider making or continuing certain loans and extending or continuing to
extend credit from time to time to Orion HealthCorp, Inc., Baytown SurgiCare,
Inc., Bellaire ASC L.P., Bellaire SurgiCare, Inc., Dennis Cain Management,
L.L.C., Dennis Cain Physician Solutions, Ltd., Integrated Physician Solutions,
Inc., IntegriMED, Inc., Medical Billing Services, Inc., San Jacinto Surgery
Center, Ltd., SurgiCare Memorial Village, L.P., TASC Anesthesia, LLC, Town &
Country SurgiCare, Inc., Tuscarawas Ambulatory Surgery Center, LLC, and
Tuscarawas Open MRI, LP, and certain affiliated entities that may from time to
time become a Borrower under the Loan Agreement (as defined below)
(individually, each a "Borrower" and collectively, "Borrowers") the Undersigned,
intending to be legally bound hereby guarantees the unconditional payment and
performance to you of all of the Obligations of Borrowers to you (including,
without limitation, interest owing to you after the commencement of a bankruptcy
proceeding at the rate specified in the Loan Agreement, whether or not such
claim is an allowable claim in such proceeding). Notwithstanding the foregoing,
the Undersigned's liability shall be limited to (A) the amount of the
Obligations due and owing as of the Guaranty Payment Date (as defined below) in
an amount not to exceed Five Hundred Two Thousand Two Hundred Seventy Three
Dollars ($502,273.00), plus (B) interest on the Obligations after the Guaranty
Payment Date and any and all fees, costs and expenses, including, without
limitation, reasonable attorneys' fees, incurred by you at any time to enforce,
protect, preserve, or defend your rights hereunder and with respect to any
property securing this Guaranty Agreement ("Liability Limit"). All payments
hereunder shall be made in lawful money of the United States, in immediately
available funds. Unless otherwise defined herein, all capitalized terms shall
have the respective meanings given to such terms in that certain Loan and
Security Agreement dated December 15, 2004 among Borrowers and you (as it may
hereafter be supplemented, amended or replaced from time to time, the "Loan
Agreement"). This Amended and Restated Guaranty Agreement ("Guaranty Agreement")
amends and restates that certain Guaranty Agreement dated December 15, 2004
executed by the Undersigned in favor of you.

      For purposes hereof, "Guaranty Payment Date" shall mean the earliest to
occur of: (i) the ninetieth (90th) day following the date that the Obligations
are accelerated or otherwise become immediately due and payable, (ii) the
ninetieth (90th) day following the last day of the Initial Term, (iii) the date
Borrowers, or any of them, become the subject of any assignment for the benefit
of creditors, bankruptcy, liquidation or other insolvency proceeding, (iv) the
date on which substantially all of the assets or stock, membership or other
equity interests of Borrowers, or any of them, is sold unless otherwise
consented to by you in writing and (v) the date on which you determine, in your
reasonable business judgment that you have substantially completed your
collection and liquidation efforts with respect to the Collateral.

      Each of the Undersigned further undertakes and agrees as follows:

      (1)   The Undersigned represents and warrants that:

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            (a)   The Undersigned's execution and performance of this Guaranty
Agreement shall not (i) violate or result in a default or breach (immediately or
with the passage of time) under any contract, agreement or instrument to which
the Undersigned is a party, or by which the Undersigned is bound, (ii) violate
or result in a default or breach under any order, decree, award, injunction,
judgment, law, regulation or rule, (iii) cause or result in the imposition or
creation of any lien upon any property of the Undersigned, or (iv) if
applicable, violate or result in a breach of the articles of incorporation,
by-laws or partnership agreement of the Undersigned.

            (b)   The Undersigned has the full power and capacity to enter into
and perform under this Guaranty Agreement.

            (c)   No consent, license or approval of, or filing or registration
with, any governmental authority is necessary for the execution and performance
hereof by the Undersigned.

            (d)   This Guaranty Agreement constitutes the valid and binding
obligation of the Undersigned enforceable in accordance with its terms, except
as such enforceability may be limited by creditors' rights generally and general
principles of equity.

            (e)   This Guaranty Agreement promotes and furthers the business and
interests of the Undersigned and the creation of the obligations hereunder will
result in direct financial benefit to the Undersigned.

      (2)   The Undersigned hereby waives notice of (a) acceptance of this
Guaranty Agreement, (b) the existence or incurring from time to time of any
Obligations guaranteed hereunder, (c) the existence of any Event of Default, the
making of demand, or the taking of any action by you, under the Loan Agreement,
and (d) demand and default hereunder.

      (3)   The Undersigned hereby consents and agrees that you may at any time
or from time to time in your discretion (a) extend or change the time of
payment, and/or the manner, place or terms of payment of any or all Obligations,
(b) amend, supplement or replace the Loan Agreement or any related agreements,
(c) renew, extend, modify, increase (without limit of any kind and whether
related or unrelated) or decrease loans and extensions of credit to Borrower,
(d) modify the terms and conditions under which loans and extensions of credit
may be made to Borrower, (e) settle, compromise or grant releases for
liabilities of Borrower, and/or any other person or persons liable with
Undersigned for, any Obligations, (f) exchange, release, surrender, sell,
subordinate, or compromise any collateral of any party now or hereafter securing
any of the Obligations, and (g) apply any and all payments received by you at
any time against the Obligations in any order as you may determine; all of the
foregoing in such manner and upon such terms as you may see fit, and without
notice to or further consent from the Undersigned, who hereby agrees to be and
shall remain bound upon this Guaranty Agreement notwithstanding any such action
on your part. The Undersigned also waives any defense, right of setoff, claim or
counterclaim whatsoever and any and all other rights, benefits, protections and
other defenses available to the Undersigned now or at any time hereafter.

      (4)   The liability of the Undersigned hereunder is absolute and
unconditional and shall not be reduced, impaired or affected in any way by
reason of (a) any failure to obtain, retain or preserve, or the lack of prior
enforcement of, any rights against any person or persons (including Borrower and
the Undersigned) or in any property, (b) the invalidity or unenforceability of
any

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Obligations or rights in any Collateral, (c) any delay in making demand upon
Borrower or any delay in enforcing, or any failure to enforce, any rights
against Borrower, or in any Collateral even if such rights are thereby lost, (d)
any failure, neglect or omission on your part to obtain, perfect or retain any
lien upon, protect, exercise rights against, or realize on, any property of
Borrower, the Undersigned, or any other party securing the Obligations, (e) the
existence or nonexistence of any defenses which may be available to the
Borrower, with respect to the Obligations, or (f) the commencement of any
bankruptcy, reorganization, liquidation, dissolution or receivership proceeding
or case filed by or against Borrower.

      (5)   If any or all payments made from time to time to you with respect to
any obligation hereby guaranteed are recovered from, or repaid by, you in whole
or in part in any bankruptcy, reorganization, insolvency or similar proceeding
instituted by or against Borrower or either of them, this Guaranty Agreement
shall continue to be fully applicable to such obligation to the same extent as
if the recovered or repaid payment(s) had never been originally made on such
obligation.

      (6)   All rights and remedies hereunder and under the Loan Agreement, and
related agreements, are cumulative and not alternative. You may proceed in any
order from time to time against Borrower and/or any other obligor of Borrower's
Obligations (other than the Undersigned) and their respective assets. From and
after the Guaranty Payment Date you shall not have any obligation to proceed
against, or exhaust any or all of your rights against Borrower or any other
obligor of Borrower's Obligations and their respective assets, prior to
proceeding against the Undersigned hereunder.

      (7)   Any and all rights of any nature of the Undersigned to subrogation,
reimbursement or indemnity and any right of the Undersigned to recourse to any
assets or property of Borrower for any reason are hereby unconditionally waived,
until such time as the Obligations of Borrower to Lender are indefeasibly paid
and satisfied in full.

      (8)   Your books and records of any and all of Borrower's Obligations,
absent manifest error, shall be prima facie evidence against the Undersigned of
the indebtedness due you or to become due to you hereunder.

      (9)   This Guaranty Agreement shall constitute a continuing guaranty
obligation with respect to all Obligations from time to time incurred or arising
and the liability of the Undersigned under this Guaranty Agreement may not be
revoked or terminated.

      (10)  The Undersigned agrees that you shall have a right of setoff against
any and all property of the Undersigned now or at any time in your possession,
including, without limitation, deposit accounts, and the proceeds thereof, as
security for the obligations of the Undersigned hereunder.

      (11)  If an Event of Default occurs under the Loan Agreement, then all of
the Undersigned's liabilities of every kind or nature to you hereunder shall, at
your option, become immediately due and payable and you may at any time and from
time to time after the occurrence of the Guaranty Payment Date take any and/or
all actions and enforce all rights and remedies available hereunder or under
applicable law to collect the Undersigned's liabilities hereunder.

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      (12)  Failure or delay in exercising any right or remedy against the
Undersigned hereunder shall not be deemed a waiver thereof or preclude the
exercise of any other right or remedy hereunder. No waiver of any breach of or
provision of this Guaranty Agreement shall be construed as a waiver of any
subsequent breach or of any other provision. The invalidity or unenforceability
of any provision hereof shall not affect the remaining provisions which shall
remain in full force and effect.

      (13)  This Guaranty Agreement shall (a) be legally binding upon the
Undersigned, and the Undersigned's successors and assigns, provided that the
Undersigned's obligations hereunder may not be delegated or assigned without
your prior written consent and (b) benefit any and all of your successors and
assigns. Signature by facsimile shall bind the Undersigned.

      (14)  This Guaranty Agreement embodies the whole agreement and
understanding of the parties hereto relative to the subject matter hereof. No
modification or waiver of any provision hereof shall be enforceable unless
approved by you in writing.

      (15)  This Guaranty Agreement shall in all respects be interpreted,
construed and governed by the substantive laws of the State of New York. The
Undersigned irrevocably (a) submits to the jurisdiction of the state courts of
the State of New Jersey and the United States District Court for the District of
New Jersey for the purposes of any litigation or proceeding hereunder or
concerning the terms hereof and (b) WAIVES THE RIGHT TO A JURY TRIAL WITH
RESPECT TO ANY LITIGATION OR PROCEEDING HEREUNDER OR CONCERNING THE TERMS
HEREOF.

      (16)  (a)   In any action or proceeding brought by you to enforce the
terms hereof, the Undersigned waives personal service of the summons, complaint,
and any motion or other process, and agrees that notice thereof may be served by
registered or certified mail, return receipt requested or by nationally
recognized overnight courier at the address of the Undersigned set forth below.
Such service shall be deemed made on the date of delivery at such address.

            (b)   Any and all notices which may be given to the Undersigned by
you hereunder shall be sent to the Undersigned at the address of the Undersigned
set forth below and shall be deemed given to and received (on the date
delivered) by the Undersigned if personally delivered or if sent by facsimile
transmission or if sent in the manner provided for service of process in
paragraph 16(a) above or as otherwise provided in accordance with terms of the
Loan Agreement.

                  [Remainder of Page Intentionally Left Blank]

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DATED the date and year first above written:

                                     BRANTLEY CAPITAL CORPORATION

                                     By: /s/ Paul H. Cascio
                                         ---------------------------------------
                                     Name: Paul H. Cascio
                                     Title: Vice President

                                     Address: Lakepoint
                                              3201 Enterprise Parkway, Suite 350
                                              Beachwood, Ohio 44122

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