Exhibit 4.12


EXECUTION
VERSION


SECOND SUPPLEMENTAL INDENTURE


SECOND SUPPLEMENTAL INDENTURE, dated as of May 29, 2007 (this “Supplemental
Indenture”), to that certain Indenture,
dated as of September 22, 2005 (as amended, restated, supplemented or otherwise
modified from time to time, the “Indenture”) among InSight Health
Services Corp., a Delaware corporation (the “Company”), InSight Health
Services Holdings Corp., a Delaware corporation (the “Parent”), the
Subsidiary Guarantors (as defined therein) and U.S. Bank National Association,
a national banking association, as trustee (in such capacity, the “Trustee”)
for the Senior Secured Floating Rate Notes due 2011.


WHEREAS, Section 9.02 of the Indenture provides,
among other things, that subject to certain restrictions, the Company, when
authorized by a Board Resolution, may amend or supplement the Notes, the
Security Documents or the Indenture with the consent (evidenced as provided in
Section 13.14 of the Indenture) of the holders of not less than a majority in
aggregate principal amount of the Notes at the time outstanding;


WHEREAS, certain holders of not less than a
majority in aggregate principal amount of the Notes outstanding as of the date
hereof (the “Initial Consenting Holders”) have duly consented to the
proposed amendments to the Indenture set forth in this Supplemental Indenture,
in accordance with the provisions of Section 9.02 and Section 13.14 of the
Indenture;


WHEREAS, all conditions necessary to authorize
the execution and delivery of this Supplemental Indenture and to make this
Supplemental Indenture valid and binding have been complied with or have been
done or performed;


NOW, THEREFORE, in consideration of the
foregoing, the parties hereto, intending to be legally bound hereby, agree as
follows:


ARTICLE I


CONTEMPORANEOUS WAIVER


The parties hereby acknowledge the execution and
delivery, contemporaneously herewith. of that certain Waiver and Agreement No.
1 to the Indenture (the “Waiver”), which Waiver, subject to the terms
and conditions set forth therein, waives or otherwise affects the Company’s
obligations to comply with certain provisions of the Indenture.


ARTICLE II


AMENDMENTS


Section 2.1.            Amendment to Definition of “Notes”.  The
definition of “Notes” is hereby deleted in its entirety and replaced with the
following:


“Notes” means the Senior Secured Floating
Rate Notes due 2011 of the Company issued on the date hereof and the Exchange
Notes.  The Notes and, upon their
issuance, the Additional Notes shall be “Notes” and treated as a single class
for all purposes under this Indenture.












Section 2.2             Amendment to Definition of “Permitted
Investments”.  Clause (i) of the definition of “Permitted
Investments” is hereby deleted in its entirety and replaced with the following:


(i)            other Investments (together with Restricted
Payments made in reliance on Section 4.07(b)(xi)) that do not exceed $20
million in the aggregate.


Section 2.3             Amendment to Definition of “Permitted Lien”. 
Clauses (23) and (24) of the definition of “Permitted Lien” are hereby
deleted in their entirety and replaced with the following:


(23)         Liens
securing Additional Notes and the related Guarantees incurred pursuant to
clauses 4.09(c)(xvi) hereof; and


(24)         Liens
not otherwise permitted by this Indenture so long as the aggregate outstanding
principal amount of the obligations secured thereby does not exceed $1.5
million at any one time outstanding.


Section 2.4.            Amendment to Optional Redemption Provision.  The
caption to Section 3.07 is hereby amended to read “Terms of Redemption” and Section
3.07(a) of the Indenture is hereby deleted in its entirety and replaced with
the following:


(a)           The
Company shall not have the option to redeem the Notes pursuant to this Section
3.07 prior to January 1, 2008. 
Thereafter, the Company may redeem all or a part of the Notes from time
to time, upon not less than 30 days’ (or, if all of the Notes are then held by
an Initial Purchaser and/or any of its affiliates, 15 days) nor more than 60
days’ notice, at the redemption prices (expressed as percentages of principal
amount) set forth below plus accrued and unpaid interest and Liquidated
Damages, if any, thereon, to the applicable redemption date, if redeemed during
the twelve-month period beginning on January 1 of the years indicated below
(subject to the right of Holders on the relevant record date to receive
interest due on the related interest payment date):


	
  Year

  	
   

  	
  Percentage

  	
   

  
	
  2008

  	
   

  	
  103.00

  	
  %

  
	
  2009 and thereafter

  	
   

  	
  102.00

  	
  %

  



 


The Company acknowledges
that the prepayment premium set forth in this Section 3.07(a) is due
upon any optional redemption and upon any other prepayment with respect to
which a redemption price is not otherwise specified regardless of whether such
prepayment is made voluntarily or mandatorily, as a result of acceleration upon
the occurrence of an Event of Default or otherwise; provided that any
Change of Control Offer shall be governed by Section 4.14 hereof and not by the
provisions of this Section 2.4.



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Section 2.5.            Amendment to Restricted Payments Covenant.  Section
4.07 of the Indenture is hereby deleted in its entirety and replaced with the
following:


(a)           The
Company shall not, and shall not permit any Restricted Subsidiary to, directly
or indirectly, take any of the following actions:


(i)            declare or pay any dividend on, or make any
distribution to holders of, any shares of the Capital Stock of the Company or
any Restricted Subsidiary, other than (i) dividends or distributions
payable solely in Qualified Equity Interests or (ii) dividends or distributions
by a Restricted Subsidiary payable to the Company or a Wholly Owned Restricted
Subsidiary or to all holders of Capital Stock of such Restricted Subsidiary on
a pro rata basis;


(ii)           purchase, redeem or otherwise acquire or retire for value, directly or
indirectly, any shares of Capital Stock, or any options, warrants or other
rights to acquire such shares of Capital Stock, of the Company, any direct or
indirect parent of the Company or any Subsidiary of the Company (other than a
Wholly Owned Restricted Subsidiary);


(iii)          make any principal payment on, or repurchase, redeem, defease or
otherwise acquire or retire for value, prior to any scheduled principal
payment, sinking fund payment or maturity, any Subordinated Indebtedness;


and


(iv)          make any Investment (other than a Permitted Investment) in any Person
(such payments or other actions described in (but not excluded from)
clauses (a) through (d) being referred to as “RESTRICTED PAYMENTS”).


(b)           Notwithstanding
the foregoing, the Company and its Restricted Subsidiaries may take the
following actions, so long as no Default or Event of Default has occurred and
is continuing or would occur:


(i)            INTENTIONALLY OMITTED;


(ii)           the repurchase, redemption or other acquisition or retirement for value
of any shares of Capital Stock of the Company, in exchange for, or out of the
net cash proceeds of a substantially concurrent issuance and sale (other than
to a Subsidiary) of, Qualified Equity Interests of the Company or of the
Parent, the proceeds of which are contributed to the Company as a capital
contribution on a substantially concurrent basis;


(iii)          the purchase, redemption, defeasance or other acquisition or retirement
for value of any Subordinated Indebtedness in exchange for, or out of the net
cash proceeds of a substantially concurrent issuance and sale (other than to a
Subsidiary) of, shares of Qualified Equity Interests of the Company or of the
Parent, the proceeds of which are contributed to the Company as a capital
contribution on a substantially concurrent basis;



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(iv)          the purchase, redemption, defeasance or other acquisition or retirement
for value of Subordinated Indebtedness in exchange for, or out of the net cash
proceeds of a substantially concurrent issuance or sale (other than to a
Subsidiary) of, Subordinated Indebtedness, so long as the Company or a
Restricted Subsidiary would be permitted to refinance such original
Subordinated Indebtedness with such new Subordinated Indebtedness pursuant to
clause (iv) of the definition of Permitted Indebtedness;


(v)           the repurchase of any Subordinated Indebtedness at a purchase price not
greater than 101% of the principal amount of such Subordinated
Indebtedness in the event of a Change of Control in accordance with provisions
similar to Section 4.14 hereof; provided that prior to or simultaneously
with such repurchase, the Company has made the Change of Control Offer as
provided in Section 4.14 hereof with respect to the Notes and has
repurchased all Notes validly tendered for payment in connection with such
Change of Control Offer;


(vi)          within 90 days after the completion of an Excess Proceeds Offer
pursuant to Section 4.10 hereof (including the purchase of all Notes
tendered), any purchase or redemption of Indebtedness of the Company that is
subordinated in right of payment to the Notes and that is required to be
repurchased or redeemed pursuant to the terms thereof as a result of the
related Asset Sale, at a purchase price not greater than 100% of the
outstanding principal amount thereof (plus accrued and unpaid interest);


(vii)         the purchase, redemption, acquisition, cancellation or other retirement
for value of shares of Capital Stock of the Company, options on any such shares
or related stock appreciation rights or similar securities, or any dividend,
distribution or advance to the Parent for the purchase, redemption,
acquisition, cancellation or other retirement for value of shares of Capital
Stock of the Parent, options on any such shares or related stock appreciation
rights or similar securities, in each case held by officers, directors or
employees or former officers, directors or employees (or their estates or
beneficiaries under their estates) of the Company, the Parent or any Subsidiary
of the Company, as applicable, or by any employee benefit plan of the Company,
the Parent or any Subsidiary of the Company, as applicable, upon death,
disability, retirement or termination of employment or pursuant to the terms of
any employee benefit plan or any other agreement under which such shares of
stock or related rights were issued; provided that the aggregate amount of cash
applied by the Company for such purchase, redemption, acquisition, cancellation
or other retirement of such shares of Capital Stock of the Company or the
Parent after the Reference Date does not exceed $3 million in the
aggregate (excluding for purposes of calculating such amount the aggregate
amount received by any Person in connection with such purchase, redemption,
acquisition, cancellation or other retirement of such shares that is
concurrently used to repay loans made to such Person by the Company pursuant to
clause (f) of the definition of “Permitted Investment”);


(viii)        the payment of dividends or other distributions or the making of loans
or advances to the Parent in amounts required for the Parent to pay franchise
taxes and other fees required to maintain its existence and provide for all
other



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customary operating costs of the Parent to
the extent attributable to the ownership and operation of the Company and its
Restricted Subsidiaries, including, without limitation, in respect of director
fees and expenses, administrative, legal and accounting services provided by
third parties and other customary costs and expenses including all costs and
expenses with respect to filings with the SEC;


(ix)           the payment of dividends or other distributions by the Company to the
Parent in amounts required to pay the tax obligations of the Parent
attributable to the Company and its Subsidiaries, determined as if the Company
and its Subsidiaries had filed a separate consolidated, combined or unitary
return for the relevant taxing jurisdiction; provided that (x) the amount
of dividends paid pursuant to this clause (ix) to enable the Parent to pay
Federal and state income taxes (and franchise taxes based on income) at any
time shall not exceed the amount of such Federal and state income taxes (and
franchise taxes based on income) actually owing by the Parent at such time to
the respective tax authorities for the respective period and (y) any
refunds received by the Parent attributable to the Company or any of its
Restricted Subsidiaries shall promptly be remitted by the Parent to the Company
through a contribution or purchase of common stock (other than Disqualified
Stock) of the Company; and


(x)            INTENTIONALLY OMITTED;


(xi)           Restricted Payments deemed to have been made as a result of a
Restricted Subsidiary being designated an Unrestricted Subsidiary in accordance
with Section 4.16(a) in an amount not to exceed $10 million at any one time
outstanding.


(c)           For
the purpose of making any calculations under this Indenture (i) if a
Restricted Subsidiary is designated an Unrestricted Subsidiary, the Company
will be deemed to have made an Investment in an amount equal to the greater of
the fair market value or net book value of the net assets of such Restricted
Subsidiary at the time of such designation as determined by the Board of the
Company, and (ii) any property transferred to or from an Unrestricted
Subsidiary will be valued at fair market value at the time of such transfer, as
determined by the Board of the Company. 
The amount of all Restricted Payments (other than cash) shall be the
fair market value on the date of the Restricted Payment of the asset(s) or
securities proposed to be transferred or issued by the Company or such Restricted
Subsidiary, as the case may be, pursuant to the Restricted Payment.  The fair market value of any non-cash
Restricted Payment shall be determined by the Board of the Company whose
resolution with respect thereto shall be delivered to the Trustee, such determination
to be based upon an opinion or appraisal issued by an accounting, appraisal or
investment banking firm of national standing if such fair market value exceeds
$10 million.  Not later than the
date of making any Restricted Payment, the Company shall deliver to the Trustee
an Officers’ Certificate stating that such Restricted Payment is permitted and
setting forth the basis upon which the calculations required under this
Section 4.07 were computed, together with a copy of any fairness opinion
or appraisal required by this Indenture.



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If the aggregate amount of all Restricted
Payments calculated under the foregoing provision includes an Investment in an
Unrestricted Subsidiary or other Person that thereafter becomes a Restricted
Subsidiary, the aggregate amount of all Restricted Payments calculated under
the foregoing provision will be reduced by the lesser of (x) the net asset
value of such Subsidiary at the time it becomes a Restricted Subsidiary and
(y) the initial amount of such Investment.


If an Investment resulted in the making of a
Restricted Payment, the aggregate amount of all Restricted Payments calculated
under the foregoing provision will be reduced by the amount of any net
reduction in such Investment (resulting from the payment of interest or
dividends, loan repayment, transfer of assets or otherwise, other than the
redesignation of an Unrestricted Subsidiary or other Person as a Restricted
Subsidiary), to the extent such net reduction is not included in the Company’s
Consolidated Net Income; provided that the total amount by which the aggregate
amount of all Restricted Payments may be reduced may not exceed the lesser of
(x) the cash proceeds received by the Company and its Restricted
Subsidiaries in connection with such net reduction and (y) the initial
amount of such Investment.


Section 2.6.            Amendment to Permitted Indebtedness Covenant. 
Section 4.09 of the Indenture is hereby deleted in its entirety and
replaced with the following:


(a)           The
Company will not, and will not permit any Restricted Subsidiary to, create,
issue, assume, guarantee or in any manner become directly or indirectly liable
for the payment of, or otherwise incur (collectively, “INCUR”), any
Indebtedness (including Acquired Indebtedness and the issuance of Disqualified
Stock), except that the Company and any Subsidiary Guarantors may incur
Indebtedness if, at the time of such event, the Fixed Charge Coverage Ratio for
the immediately preceding four full fiscal quarters for which internal
financial statements are available, taken as one accounting period, would have
been equal to at least 2.0 to 1.0.


(b)           In
making the foregoing calculation, pro forma effect will be given to:


(i)            the incurrence of such Indebtedness and (if
applicable) the application of the net proceeds therefrom, including to
refinance other Indebtedness, as if such Indebtedness was incurred and the
application of such proceeds occurred at the beginning of such four-quarter
period;


(ii)           the incurrence, repayment or retirement of any other Indebtedness by
the Company or its Restricted Subsidiaries since the first day of such
four-quarter period as if such Indebtedness was incurred, repaid or retired at
the beginning of such four-quarter period; and



 6
 








(iii)          the acquisition (whether by purchase, merger or otherwise) or
disposition (whether by sale, merger or otherwise) of any company, entity or
business acquired or disposed of by the Company or its Restricted Subsidiaries,
as the case may be, since the first day of such four-quarter period, as if such
acquisition or disposition occurred at the beginning of such four-quarter
period.  In making a computation under
the foregoing clause (i) or (ii), (A) the amount of Indebtedness
under a revolving credit facility will be computed based on the average daily
balance of such Indebtedness during such four-quarter period, (B) if
such Indebtedness bears, at the option of the Company, a fixed or floating rate
of interest, interest thereon will be computed by applying, at the option of
the Company, either the fixed or floating rate, and (C) the amount of any
Indebtedness that bears interest at a floating rate will be calculated as if the rate in effect on the date of determination had
been the applicable rate for the entire period (taking into account any Hedging
Obligations applicable to such Indebtedness if such Hedging Obligations have a
remaining term at the date of determination in excess of 12 months).


(c)           Notwithstanding
the foregoing, the Company may, and may permit its Restricted Subsidiaries to,
incur the following Indebtedness (“PERMITTED INDEBTEDNESS”):


(i)            Indebtedness of the Company or any Subsidiary
Guarantor under the Credit Agreement (and the incurrence by any Subsidiary
Guarantor of guarantees thereof) in an aggregate principal amount at any one
time outstanding not to exceed $125 million, less (A) any amounts
applied to the permanent reduction of such credit facilities pursuant to the
provisions of Section 4.10 hereof and (B) up to $50 million of
cash (or the fair market value of any other assets) to the extent applied to
repurchase Existing Notes on the Issue Date or within two Business Days from
the Issue Date;


(ii)           Indebtedness represented by the Notes (other than the Additional Notes)
and the related Guarantees;


(iii)          Existing Indebtedness;


(iv)          the incurrence by the Company of Permitted Refinancing Indebtedness in
exchange for, or the net cash proceeds of which are used to refund, refinance
or replace, any Indebtedness that is permitted to be incurred under
clause (ii) or (iii) above;


(v)           Indebtedness owed by the Company to any Restricted Subsidiary or owed
by any Restricted Subsidiary to the Company or a Restricted Subsidiary
(provided that such Indebtedness is held by the Company or such Restricted
Subsidiary); provided that:



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(A)          any Indebtedness of the Company or any Subsidiary Guarantor owing to
any such Restricted Subsidiary is unsecured and subordinated in right of
payment from and after such time as the Notes shall become due and payable
(whether at Stated Maturity, acceleration, or otherwise) to the payment and
performance of the Company’s obligations under the Notes or the Subsidiary
Guarantor’s obligations under its Guarantee, as the case may be; and


(B)           (x) any subsequent issuance or transfer of Equity Interests that
results in any such Indebtedness being held by a Person other than the Company
or a Restricted Subsidiary thereof and (y) any sale or other transfer of
any such Indebtedness to a Person that is not either the Company or a
Restricted Subsidiary thereof, shall be deemed, in each case, to constitute an
incurrence of such Indebtedness by the Company or such Restricted Subsidiary,
as the case may be, that was not permitted by this clause (v);


(vi)          Indebtedness of the Company or any Restricted Subsidiary under Hedging
Obligations incurred in the ordinary course of business;


(vii)         Indebtedness of the Company or any Restricted Subsidiary consisting of
guarantees, indemnities or obligations in respect of purchase price adjustments
in connection with the acquisition or disposition of assets, including, without
limitation, shares of Capital Stock;


(viii)        either (A) Capitalized Lease Obligations of the Company or any
Restricted Subsidiary or (B) Indebtedness under purchase money mortgages
or secured by purchase money security interests so long as (x) such
Indebtedness is not secured by any property or assets of the Company or any
Restricted Subsidiary other than the property and assets so acquired and
(y) such Indebtedness is created within 90 days of the acquisition of
the related property; provided that the aggregate amount of Indebtedness under
clauses (A) and (B) does not exceed 15% of Consolidated Tangible
Assets less the amount of any Indebtedness incurred under clause (xvi)
below at any one time outstanding;


(ix)           Guarantees by any Restricted Subsidiary made in accordance with the
provisions of Section 4.18 hereof;


(x)            Indebtedness arising from the honoring by a
bank or other financial institution of a check, draft or similar instrument
inadvertently (except in the case of daylight overdrafts) drawn against
insufficient funds in the ordinary course of business; provided that such
Indebtedness is extinguished within two business days of incurrence;


(xi)           Indebtedness of the Company or any of its Restricted Subsidiaries
represented by letters of credit for the account of the Company or such
Restricted Subsidiary, as the case may be, in order to provide security for
workers’ compensation claims, payment obligations in connection with
self-insurance or similar requirements in the ordinary course of business;


(xii)          the incurrence of Non-Recourse Indebtedness by Permitted Joint Ventures
that are Restricted Subsidiaries;



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(xiii)         Indebtedness incurred by a Receivables Subsidiary pursuant to a
Receivables Program; provided that, after giving effect to any such incurrence
of Indebtedness, the aggregate principal amount of all Indebtedness incurred
under this clause (xiii) and then outstanding does not exceed
$30 million;


(xiv)        unsecured subordinated Indebtedness not permitted by any other clause
of this definition, in an aggregate principal amount not to exceed $30 million
at any one time outstanding;


(xv)         Indebtedness represented by Attributable Debt related to a Sale and
Leaseback transaction involving tractors existing on the Issue Date; provided
that (i) the aggregate amount of such Indebtedness does not exceed
$7 million and (ii) such Indebtedness is incurred within
12 months from the Issue Date; and


(xvi)        the incurrence of Indebtedness represented by Additional Notes and the
related Guarantees in an aggregate principal amount of $15 million.


(d)           The
Company will not incur any Indebtedness that is subordinate in right of payment
to any other Indebtedness of the Company unless it is subordinate in right of
payment to the Notes to the same extent. 
The Company will not permit any Subsidiary Guarantor to incur any
Indebtedness that is subordinate in right of payment to any other Indebtedness
of such Subsidiary Guarantor unless it is subordinate in right of payment to
such Subsidiary Guarantor’s Guarantee to the same extent.  For purposes of the foregoing, no
Indebtedness will be deemed to be subordinated in right of payment to any other
Indebtedness of the Company or any Subsidiary Guarantor, as applicable, solely
by reason of any Liens or Guarantees arising or created in respect thereof or
by virtue of the fact that the holders of any secured Indebtedness have entered
into intercreditor agreements giving one or more of such holders priority over
the other holders in the collateral held by them.


(e)           For
purposes of determining compliance with this Section 4.09, in the event
that any proposed Indebtedness meets the criteria of more than one of the
categories of Permitted Indebtedness described in clauses (i) through
(xvi) above, or is entitled to be incurred pursuant to Section 4.09(a)
hereof, the Company will be permitted to classify such item of Indebtedness on
the date of its incurrence, or later reclassify all or a portion of such item
of Indebtedness, in any manner that complies with this Section 4.09.  Indebtedness under the Credit Agreement
incurred on the Issue Date shall be deemed to have been incurred on the Issue
Date in reliance on the exception provided by clause (i) of the definition
of Permitted Indebtedness.


Section 2.7.            Amendment to Asset Sale Covenant.  Section
4.10 of the Indenture is hereby deleted in its entirety and replaced with the
following:


(a)           The
Company will not, and will not permit any Restricted Subsidiary to, engage in
any Asset Sale unless:



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(i)            the
consideration received by the Company or such Restricted Subsidiary for such
Asset Sale is not less than the fair market value of the assets sold evidenced
by a resolution of the board of directors of such entity set forth in an
Officers’ Certificate delivered to the Trustee; provided that if the fair
market value of the assets sold exceeds $5 million, such determination will at
the option of the Company be based upon an opinion or appraisal issued by an
accounting or investment banking or appraisal firm of national standing, a copy
of which opinion or appraisal shall accompany the Officers’ Certificate;


(ii)           the
consideration received by the Company or the relevant Restricted Subsidiary in
respect of such Asset Sale consists of at least 75% cash or Cash Equivalents
(for purposes of this clause (ii), cash and Cash Equivalents includes
(1) if such Asset Sale does not involve Collateral, any liabilities (as
reflected in the Company’s consolidated balance sheet) of the Company or any
Restricted Subsidiary (other than contingent liabilities and liabilities that
are by their terms subordinated to the Notes or any Guarantee) that are assumed
by any transferee of any such assets or other property in such Asset Sale, and
where the Company or the relevant Restricted Subsidiary is released from any
further liability in connection therewith with respect to such liabilities,
(2) any securities, notes or other similar obligations received by the
Company or any such Restricted Subsidiary from such transferee that are
converted within 180 days of the consummation of the related Asset Sale by
the Company or such Restricted Subsidiary into cash and Cash Equivalents (to
the extent of the net cash proceeds or the Cash Equivalents (net of related
costs) received upon such conversion), (3) any Designated Noncash Consideration
received by the Company or any such Restricted Subsidiary in the Asset Sale
having an aggregate fair market value, as determined by the Board of the
Company, taken together with all other Designated Noncash Consideration
received pursuant to this clause that has not been converted into cash or Cash
Equivalents, not to exceed $10 million; and


(iii)          if such Asset Sale involves the transfer of
Collateral,


(1)           all
consideration received in such Asset Sale shall consist of assets that are not
Excluded Assets; and


(2)           all
consideration (including cash and cash equivalents) received in such Asset Sale
shall be expressly made subject to a first-priority perfected Lien (subject to
Permitted Liens) in favor of the Collateral Agent;.


(b)           If the
Company or any Restricted Subsidiary engages in an Asset Sale, the Company may,
at its option, within 12 months after such Asset Sale (i) apply all
or a portion of the Net Cash Proceeds to repay or purchase Applicable
Indebtedness (and, in the case of revolving loans and other similar
obligations, permanently reduce the commitment thereunder), or (ii) invest
(or enter into a legally binding agreement to invest) all or a portion of such
Net Cash Proceeds in properties and assets to replace the properties and assets
that were the subject of the Asset Sale or in properties and assets that will
be used in businesses of the



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Company or its Restricted Subsidiaries, as the case may be, existing on
the Issue Date or in businesses the same, similar or reasonably related
thereto; provided, that, to the extent that such Net Cash Proceeds represent
proceeds of Collateral, (A) none of such properties and assets obtained
shall consist of Excluded Assets and (B) such properties and assets
obtained shall be expressly made subject to a perfected first-priority Lien
(subject to Permitted Liens) with respect to the Notes.  If any such legally binding agreement to
invest such Net Cash Proceeds is terminated, the Company may, within
90 days of such termination or within 12 months of such Asset Sale,
whichever is later, invest such Net Cash Proceeds as provided in
clause (i) or (ii) (without regard to the parenthetical contained in such
clause (ii)) above.  Pending the
final application of any such Net Cash Proceeds, the Company may temporarily
reduce revolving credit borrowings or otherwise invest such Net Cash Proceeds
in a manner that is not prohibited by this Indenture.  The amount of such Net Cash Proceeds not so
used as set forth above in this paragraph shall constitute “EXCESS PROCEEDS”.


(c)           When the aggregate
amount of Excess Proceeds exceeds $10 million, the Company will, within
30 days thereafter, make an offer to purchase (an “EXCESS PROCEEDS OFFER”)
from all Holders of Notes on a pro rata basis, in accordance with the
procedures set forth in this Indenture, the maximum principal amount (expressed
as a multiple of $1,000) of Notes that may be purchased with the Excess
Proceeds, at a purchase price in cash equal to that percentage of the principal
amount thereof that would be required to be paid pursuant to Section 3.07(a)
if such Excess Proceeds Offer were an optional redemption, plus accrued
interest and Liquidated Damages, if any, to the date such offer to purchase is
consummated.  To the extent that the
aggregate principal amount of Notes tendered pursuant to such offer to purchase
is less than the Excess Proceeds, the Company may use such deficiency for
general corporate purposes.  If the
aggregate principal amount of Notes validly tendered and not withdrawn by
holders thereof exceeds the Excess Proceeds, the Notes to be purchased will be
selected on a pro rata basis.  Upon
completion of such offer to purchase, the amount of Excess Proceeds will be
reset to zero.


Section 2.8             Additional
Event of Default.  Section 6.01 of
the Indenture is hereby amended by (a) removing the word “or” from clause (ix)
thereof; (b) removing the “.” at then of clause (x) thereof and replacing
it with “; or”; and (c) adding as clause (xi) thereof the following:


(xi)           failure by the
Company to issue Additional Notes in an aggregate principal amount of $15
million as contemplated by the
commitment letter dated May 29, 2007 among the Company, the Parent, J.P. Morgan
Securities Inc. and Black Diamond Capital Management, L.L.C. (the “Commitment
Parties”) relating to the issuance and purchase of Additional Notes (as
amended, supplemented or otherwise modified, the “Commitment Letter”),
by the earlier of (x) the 30th day following the effective date of any plan
of reorganization or (y) the 16th day following approval of such issuance by any
court having jurisdiction over any proceeding described in clause (viii) or
(ix) of this Section 6.01 to which the Company is subject becoming a final
order (unless, in either case, the failure of



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the Company to issue any such Additional Notes is caused solely by the
failure of any Commitment Party to be ready, willing and able to consummate its
purchase thereof as contemplated by the Commitment Letter) and continuance of
such failure for a period of 30 days after written notice has been given to the
Company by any Commitment Party that was not able to purchase Additional Notes
notwithstanding that it was ready, willing and able to do so as contemplated
under the Commitment Letter.


Section 2.9             Amendment
to Acceleration Provision.  Section
6.02(a) of the Indenture is hereby deleted in its entirety and replaced with
the following:


(a)           If an Event of
Default (other than as specified in Section 6.01(viii) or (ix) hereof) occurs
and is continuing, the Trustee or the Holders of not less than 25% in aggregate
principal amount of the Note then outstanding may, and the Trustee at the
request of such Holders will, declare an amount equal to all principal, accrued
and unpaid interest and premium on all outstanding Notes, including all premium
and other amounts that may be due by reason of Section 3.07(a), immediately due
and payable and, upon any such declaration, such principal, interest and
premium shall become due and payable immediately.  The Trustee shall promptly notify the Company
of any such acceleration of the Notes pursuant to Section 6.02(a).


If an Event of Default specified in Section 6.01(viii) or (ix) hereof
occurs and is continuing, then an amount equal to all principal, accrued and
unpaid interest and premium on all outstanding Notes, including all premium and
other amounts that may be due by reason of Section 3.07(a), immediately due and
payable and, upon any such declaration, such principal, interest and premium
shall ipso facto become and be immediately due and payable without any
declaration or other act on the part of the Trustee or any Holder.


Section 2.10           Amendment to Definition of
Excluded Assets.  The definition of “Excluded Assets” in
Section 1.01 of the Indenture is hereby amended by adding the following
parenthetical immediately after the words “real property” in clause (1)
thereof:


(other than the fee interest owned by InSight
Health Corp. in the real property located at (x) 1199 Eighth Avenue, Fort
Worth, Texas 76104 and (y) 1301 McCallie Avenue, Chattanooga, Tennessee 37404,
in each case upon the granting of a mortgage and security interest by InSight
Health Corp. in such real property in favor of the Collateral Agent).


Section 2.11           Additional
Covenant Relating to Perfection of Mortgages.  The Company hereby agrees to cause InSight
Health Corp. to execute and deliver to the Collateral Agent mortgages or deeds
of trust, as the case may be, in form and substance reasonably satisfactory to
the Trustee, as soon as reasonably practicable, but in no event later than
November 29, 2007 with respect to InSight Health Corp.’s rights to and
interests in the real property located at 1199 Eighth Avenue, Fort Worth, Texas
76104, and the real property located at 1301 McCallie Avenue, Chattanooga,
Tennessee 37404, unless, in each case, such real property is sold,



 12
 









transferred
or disposed of by InSight Health Corp. prior to such date.  The Company shall, contemporaneously with the
delivery of each aforesaid mortgage or deed of trust, deliver to the Trustee
the initial perfection opinion required by Section 314(b) of the Trust
Indenture Act with respect to such mortgage or deed of trust and shall, at
least annually thereafter, provide to the Trustee all of the perfection
opinions required by Section 314(b) for all of the Collateral including the
foregoing real property.  In determining
that the form of any such mortgage or deed of trust is reasonably satisfactory,
the Trustee shall be entitled to rely upon an Officer’s Certificate indicating
that the terms of same are commercially reasonable and, subject to recordation
in the appropriate governmental office and to payment of all required filing
fees, taxes and other governmental charges required in connection with such
recordation, will be sufficient to convey a perfected lien on the real property
subject thereto.  For clarity, any sale,
transfer or other disposition of either such real property prior to the
execution and delivery of the aforesaid mortgages or deeds of trust shall be
subject to all applicable provisions of Section 4.10.


ARTICLE III


DEFINITIONS


All terms used herein and not otherwise defined herein
shall have the respective meanings assigned to them in the Indenture.


ARTICLE IV


MISCELLANEOUS


Section 4.1             Effect of Amendment.  Except as amended hereby, all of the terms of
the Indenture shall remain and continue in full force and effect and are hereby
confirmed in all respects.


Section 4.2             Governing Law.  THE INTERNAL LAWS OF THE STATE OF NEW YORK
SHALL GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE WITHOUT GIVING
EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAWS TO THE EXTENT THAT THE
APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.


Section 4.3             Counterpart Originals.  The parties may sign any number of copies of
this Supplemental Indenture.  Each signed
copy shall be an original, but all of them together represent the same
agreement.


Section 4.4             Rights of Trustee.  In entering into this Supplemental Indenture,
the Trustee shall be entitled to the benefit of every provision of the
Indenture relating to the conduct or affecting the liability of or affording
protection to the Trustee, whether or not elsewhere herein so provided.



 13
 









Section 4.5             Headings, Etc.  The headings of the Articles and Sections of
this Supplemental Indenture have been inserted for convenience of reference
only, are not to be considered a part of this Indenture and shall in no way modify
or restrict any of the terms or provisions hereof.


[REMAINDER OF PAGE
INTENTIONALLY LEFT BLANK]



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IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed and delivered by their proper and duly authorized
officers as of the day and year first above written.


	
  

  	
  COMPANY AND GUARANTORS:

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  INSIGHT HEALTH SERVICES CORP.

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Mitch C. Hill

  
	
   

  	
   

  	
  Mitch C. Hill, Executive Vice
  President and

  Chief Financial Officer

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  INSIGHT HEALTH SERVICES HOLDINGS CORP.

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Mitch C. Hill

  
	
   

  	
   

  	
  Mitch C. Hill, Executive Vice
  President and

  Chief Financial Officer

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  WILKES-BARRE IMAGING, L.L.C.

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  	
  InSight Health Corp., as the sole member and sole
  manager

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  /s/ Mitch C. Hill

  
	
   

  	
   

  	
   

  	
   

  	
  Mitch C. Hill, Executive Vice
  President

  and Chief Financial Officer

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  MRI ASSOCIATES, L.P.

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  	
  InSight Health Corp., as the general partner

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  /s/ Mitch C. Hill

  
	
   

  	
   

  	
   

  	
   

  	
  Mitch C. Hill, Executive Vice
  President

  and Chief Financial Officer

  
						



 


[Signatures
continued on following page]



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  VALENCIA
  MRI, LLC

  
	
   

  	
  ORANGE
  COUNTY REGIONAL PET CENTER-IRVINE, LLC

  
	
   

  	
  SAN
  FERNANDO VALLEY REGIONAL PET CENTER, LLC

  
	
   

  	
   

  
	
   

  	
  By:

  	
   

  	
  InSight Health Corp., as the sole member

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  /s/ Mitch C. Hill

  
	
   

  	
   

  	
   

  	
   

  	
  Mitch C. Hill, Executive Vice
  President

  and Chief Financial Officer

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
  PARKWAY IMAGING CENTER, LLC

  
	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  /s/ Mitch C. Hill

  
	
   

  	
   

  	
   

  	
   

  	
  Mitch C. Hill, Manager

  



 


[Signatures
continued on following page]



 16
 









 


	
  

  	
  INSIGHT
  HEALTH CORP.

  
	
   

  	
  OPEN
  MRI, INC.

  
	
   

  	
  MAXUM
  HEALTH CORP.

  
	
   

  	
  RADIOSURGERY
  CENTERS, INC.

  
	
   

  	
  DIAGNOSTIC
  SOLUTIONS CORP.

  
	
   

  	
  MAXUM
  HEALTH SERVICES OF NORTH TEXAS, INC.

  
	
   

  	
  MAXUM
  HEALTH SERVICES OF DALLAS, INC.

  
	
   

  	
  NDDC,
  INC.

  
	
   

  	
  SIGNAL
  MEDICAL SERVICES, INC.

  
	
   

  	
  INSIGHT
  IMAGING SERVICES CORP.

  
	
   

  	
  COMPREHENSIVE
  MEDICAL IMAGING, INC.

  
	
   

  	
  COMPREHENSIVE
  MEDICAL IMAGING CENTERS, INC.

  
	
   

  	
  COMPREHENSIVE
  MEDICAL IMAGING- BILTMORE, INC.

  
	
   

  	
  COMPREHENSIVE
  OPEN MRI-EAST MESA, INC.

  
	
   

  	
  TME
  ARIZONA, INC.

  
	
   

  	
  COMPREHENSIVE
  MEDICAL IMAGING- FREMONT, INC.

  
	
   

  	
  COMPREHENSIVE
  MEDICAL IMAGING- SAN FRANCISCO, INC.

  
	
   

  	
  COMPREHENSIVE
  OPEN MRI- GARLAND, INC.

  
	
   

  	
  IMI OF
  ARLINGTON, INC.

  
	
   

  	
  COMPREHENSIVE
  MEDICAL IMAGING- FAIRFAX, INC.

  
	
   

  	
  IMI OF
  KANSAS CITY, INC.

  
	
   

  	
  COMPREHENSIVE
  MEDICAL IMAGING- BAKERSFIELD, INC.

  
	
   

  	
  MAXUM
  HEALTH SERVICES CORP.

  
	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Mitch C.
  Hill

  
	
   

  	
   

  	
  Mitch
  C. Hill, Executive Vice President and

  Chief Financial
  Officer

  



 


[Signatures
continued on following page]



 17
 









 


	
  

  	
  COMPREHENSIVE
  OPEN MRI- CARMICHAEL/FOLSOM, LLC

  
	
   

  	
  SYNCOR
  DIAGNOSTICS SACRAMENTO, LLC

  
	
   

  	
  SYNCOR
  DIAGNOSTICS BAKERSFIELD, LLC

  
	
   

  	
   

  
	
   

  	
  By:

  	
   

  	
  Comprehensive Medical Imaging, Inc. and

  Comprehensive Medical Imaging Centers,

  Inc., as the partners

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  /s/ Mitch C. Hill

  
	
   

  	
   

  	
   

  	
   

  	
  Mitch C. Hill, Executive Vice
  President

  and Chief Financial Officer

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
  PHOENIX
  REGIONAL PET CENTER-

  
	
   

  	
   

  	
   

  	
  THUNDERBIRD, LLC

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  	
  Comprehensive Medical Imaging Centers,

  Inc., as the sole member

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  /s/ Mitch C. Hill

  
	
   

  	
   

  	
   

  	
   

  	
  Mitch C. Hill, Executive Vice
  President

  and Chief Financial Officer

  



 


[Signatures
continued on following page]



 18
 









 


	
  

  	
  MESA
  MRI

  
	
   

  	
  MOUNTAIN
  VIEW MRI

  
	
   

  	
  LOS
  GATOS IMAGING CENTER

  
	
   

  	
  WOODBRIDGE
  MRI

  
	
   

  	
  JEFFERSON
  MRI-BALA

  
	
   

  	
  JEFFERSON
  MRI

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  	
  Comprehensive Medical Imaging, Inc. and

  Comprehensive Medical Imaging Centers,

  Inc., as the members

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  /s/ Mitch C. Hill

  
	
   

  	
   

  	
   

  	
   

  	
  Mitch C. Hill, Executive Vice
  President

  and Chief Financial Officer

  



 


[Signatures
continued on following page]



 19
 









 


	
  

  	
  TRUSTEE:

  
	
   

  	
   

  
	
   

  	
  U.S. BANK NATIONAL ASSOCIATION, AS TRUSTEE

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ James E. Murphy

  
	
   

  	
  Name:

  	
  James E. Murphy

  
	
   

  	
  Title:

  	
  Vice President

  
						



 



 20