EXHIBIT 4.1


THIS NOTE AND THE SHARES OF COMMON STOCK OF U.S. DIAGNOSTIC INC. (THE "COMPANY")
INTO WHICH THIS NOTE IS CONVERTIBLE HAVE NOT BEEN REGISTERED UNDER THE
SECURITIES ACT OF 1933 NOR UNDER ANY STATE SECURITIES LAW AND MAY NOT BE
PLEDGED, SOLD, ASSIGNED OR TRANSFERRED UNTIL (i) A REGISTRATION STATEMENT WITH
RESPECT THERETO IS EFFECTIVE UNDER THE SECURITIES ACT OF 1933 AND ANY APPLICABLE
STATE SECURITIES LAW OR (ii) THE COMPANY RECEIVES AN OPINION OF COUNSEL TO THE
HOLDER OF SUCH NOTE OR COMMON STOCK REASONABLY SATISFACTORY TO THE COMPANY THAT
SUCH SHARES OR NOTE MAY BE PLEDGED, SOLD, ASSIGNED OR TRANSFERRED WITHOUT AN
EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 OR APPLICABLE
STATE SECURITIES LAWS.

                              U.S. DIAGNOSTIC INC.
                              AMENDED AND RESTATED
                       6 1/2% CONVERTIBLE NEGOTIABLE NOTE
                                DUE JUNE 30, 2001

$_____________                                              New York, New York
                                                            September __, 1997

         FOR VALUE RECEIVED, U.S. Diagnostic Inc., a Delaware corporation (the
"Company"), with its principal office at 777 S. Flagler Drive, West Palm Beach,
Florida 33401, promises to pay to the order of _________________________________
or assigns (the "Payee", "the holder of this Note" or the "Holder"), the
principal amount of _______________________________ Dollars ($____________.00),
with interest from the July 1, 1997 payable quarterly at the rate of six and
one-half percent (6 1/2%) per annum. The principal of this Note shall be due and
payable in full on June 30, 2001. Quarterly payments of accrued interest shall
commence September 30, 1997 and continue until the principal is paid or
converted in full. Accrued and unpaid interest on any portion of the Note that
is converted pursuant to the terms of Section 2 hereof will be payable through
the date of the Notice of Conversion on the principal amount converted. Interest
shall be computed based on the premise that a year contains twelve (12) thirty
(30) day months and 360 days and shall be charged on a per diem basis.

         1. EVENTS OF DEFAULT. If one or more of the following events (herein
called "Events of Default") shall have occurred and be continuing, that is to
say:

         (a) If the Company shall default in the payment of the principal and
accrued interest on this Note after the principal or accrued interest shall
become due and payable; or

         (b) If (i) the Company shall commence any proceeding or other action
relating to it in bankruptcy or seek reorganization, arrangement, readjustment
of its debts, dissolution, liquidation, winding-up, composition or any other
relief under the Bankruptcy Act, as amended, or under any other insolvency,
reorganization, liquidation, dissolution, arrangement, composition, readjustment
of debt or any other similar act or law, of any jurisdiction, domestic or
foreign, now or hereafter existing; or (ii) the Company shall admit the material
allegations of any petition or pleading in

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connection with any such proceeding; or (iii) the Company applies for, or
consents or acquiesces to, the appointment of a receiver, conservator, trustee
or similar officer for it or for all or a substantial part of its property; or
(iv) the Company makes a general assignment for the benefit of its creditors; or
(v) the Company is unable or admits in writing that it is unable to pay its
debts as they mature; or

         (c) (i) Commencement of any proceedings or in the taking of any other
action against the Company in bankruptcy or seeking reorganization, arrangement,
readjustment of its debts, liquidation, dissolution, arrangement, composition,
readjustment of debt or any other similar act or law of any jurisdiction,
domestic or foreign, now or hereafter existing and the continuance of any of
such events for twenty (20) days undismissed, unbonded or undischarged; or (ii)
the appointment of a receiver, conservator, trustee or similar officer for the
Company or for all or substantially all of its property and the continuance of
such event for thirty (30) days undismissed, unbonded or undisclosed; or (iii)
the issuance of a warrant of attachment, execution or similar process against
substantially all of the property of the Company and the continuance of such
event for thirty (30) days undismissed, unbonded and undischarged;

then the principal amount of, and all accrued interest on, this Note shall be
accelerated and become immediately due and payable in full. The Events of
Default listed herein are solely for the purpose of protecting the interests of
the holder of this Note.

         2.  CONVERSION OF NOTE.

         (a) The Payee shall have the right, by written notice to the Company as
provided herein at any time following the issuance of this Note and prior to or
on the Maturity Date, to convert all or a portion of the unpaid principal amount
of this Note plus all accrued interest thereon, into Common Stock, $.01 par
value, of the Company ("Common Stock"), at a conversion price of $8.50 per
share, subject to adjustment as hereinafter provided (as so adjusted, the
"Conversion Rate").

         (b) The Payee desiring to exercise its option to convert this Note
pursuant to clause (a) hereof, shall deliver the Note to the Company at its
principal executive office, accompanied by a signed "Notice of Conversion" in
the form attached as Exhibit A hereto, specifying the number of shares of Common
Stock to be acquired, the principal amount to be converted and the name or
names, address and social security or tax ID number in which the certificate or
certificates for shares of Common Stock are to be issued. The foregoing
notwithstanding, no holder of this Note shall be entitled to transfer this Note
by conversion without first complying with all applicable restrictions on the
transfer of this Note. The conversion will be deemed to have occurred upon the
date of delivery of this Notice and the Notice of Conversion and the person
entitled to receive share certificates for Common Stock shall be regarded for
all corporate purposes from and after such date as the record holder the number
of shares of Common Stock to which it is entitled upon the conversion. The
Company may rely on record ownership of this Note for all corporate purposes,
notwithstanding any contrary notice. Upon receipt of the Notice of Conversion,
the Company shall

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promptly issue a stock certificate for the shares of Common Stock issuable upon
conversion of the Note and shall promptly pay all accrued interest on the
portion of the Note that has been converted.

         (c) The Conversion Price in effect at any time and the number and kind
of securities purchasable upon the conversion of this Note shall be subject to
adjustment from time to time upon the happening of certain events as follows:

         (i) In case the Company shall (x) declare a dividend or make a
         distribution on its outstanding shares of Common Stock in shares of
         Common Stock, (y) subdivide or reclassify its outstanding shares of
         Common Stock into a greater number of shares, or (z) combine or
         reclassify its outstanding shares of Common Stock into a smaller number
         of shares, the Conversion Price in effect at the time of the record
         date for such dividend or distribution or of the effective date of such
         subdivision, combination or reclassification shall be adjusted so that
         it shall equal the price determined by multiplying the Conversion Price
         by a fraction, the denominator of which shall be the number of shares
         of Common Stock outstanding after giving effect to such action, and the
         numerator of which shall be the number of shares of Common Stock
         outstanding immediately prior to such action. Such adjustment shall be
         made successively whenever any event listed above shall occur.

         (ii) In the case of any reclassification, capital reorganization or
         other change of outstanding shares of Common Stock of the Company, or
         in the case of any consolidation or merger of the Company with or into
         another corporation or the conveyance of all or substantially all of
         the assets of the Company to another corporation (other than a merger
         with a subsidiary in which merger the Company is the continuing
         corporation and which does not result in any reclassification, capital
         reorganization or other change of outstanding shares of Common Stock of
         the class issuable upon conversion of this Note), this Note shall
         thereafter be convertible at the Conversion Price in effect on the day
         immediately preceding such reclassification, reorganization, merger or
         consolidation into the number of shares of stock or other securities or
         property to which a holder of the number of shares of Common Stock of
         the Company deliverable upon conversion of this Note would have been
         entitled upon such reclassification, change, consolidation, merger or
         conveyance; and, in any such case, appropriate readjustment (as
         determined by the Board of Directors) shall be made in the application
         of the provisions herein set forth with respect to the rights and
         interests thereafter of the holder of this Note, to the end that the
         provisions set forth herein (including provisions with respect to
         changes in and other adjustments of the Conversion Price) shall
         thereafter be applicable, as nearly as reasonably may be, in relation
         to any shares of stock or other property thereafter deliverable upon
         the conversion of this Note. The foregoing provisions of this
         subsection (c)(ii) shall similarly apply to successive
         reclassifications, capital reorganizations and changes of shares of
         Common Stock and to successive consolidations, mergers, sales or
         conveyances.

         (d) No fractional shares of Common Stock shall be issued upon
conversion of this Note. In the event that the principal amount stated in the
aforesaid notice to be converted would result in

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the issuance of a fractional share of Common Stock, the Company shall pay a cash
adjustment in lieu of such fractional share to the holder of this Note based
upon the closing price of a share of Common Stock on the principal securities
exchange (including the NASDAQ National Market) on which such Common Stock is
trading on the date of conversion.

         (e)      In case at any time:

         (i)      The Company shall declare any dividend upon, or other
         distribution in respect of, its Common Stock; or

         (ii) There shall be any capital reorganization or reclassification of
         the capital stock of the Company, or a sale of all or substantially all
         of the assets of the Company, or a consolidation or merger of the
         Company with another corporation (other than a merger with a subsidiary
         in which merger the Company is the continuing corporation and which
         does not result in any reclassification), or change of then outstanding
         shares of Common Stock or other capital stock issuable upon the
         conversion of this Note (other than a change in par value, or from par
         value to no par value, or from no par value to par value or as a result
         of subdivision or combination or conversion of outstanding options and
         warrants currently outstanding); or

         (iii) There shall be a voluntary or involuntary dissolution,
         liquidation or winding-up of the Company;

then, in any one or more of said cases, the Company shall cause to be mailed to
the registered holder of this Note at the earliest practicable time (and in any
event not less than 10 business days before any record date or other date set
for definitive action), written notice of the date on which the books of the
Company shall close or a record shall be taken for such dividend, distribution
or such reorganization, reclassification, sale, consolidation, merger or
dissolution, liquidation or winding-up shall take place, as the case may be.
Such notice shall also set forth such facts as shall indicate the effect of such
action (to the extent such effect may be known or can reasonably be approximated
at the date of such notice) on the Conversion Rate and the kind and amount of
the shares of stock and other securities and property deliverable upon the
conversion of this Note. Such notice shall also specify the date as of which the
holders of the Common Stock of record shall participate in said dividend,
distribution or shall be entitled to exchange their Common Stock for securities
or other property deliverable upon such reorganization, reclassification, sale,
consolidation, merger or dissolution, liquidation or winding-up, as the case may
be.

         (f) All shares of Common Stock which may be issued upon conversion of
this Note will, upon issuance the Company in accordance with the terms of this
Note be validly issued and, subject to the payment in full, in an amount equal
to the Conversion Rate of such shares multiplied by the number of shares so
issued, fully paid and non-assessable.

         3. REQUIRED CONVERSION. At any time commencing on the later of January
1, 1999 or the date that the shares of Common Stock into which this Note is
convertible are registered for resale

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by the Holder under the Securities Act of 1933, as amended (such time being
herein called the "Required Conversion Date"), if the last sale price of the
Common Stock averages at least $9.25 per share for the ten (10) trading days
immediately preceding the Required Conversion Date, then upon written notice
from the Company given within fifteen (15) days following the Required
Conversion Date, the Payee shall convert this Note at the then applicable
Conversion Rate; PROVIDED, HOWEVER, that, in the event of such notice being
given by the Company, the Payee may provide notice to the Company of its
election to receive payment in cash of the full principal balance of the Note
together with any accrued but unpaid interest, in lieu of consenting to the
conversion.

         4. PREPAYMENT. This Note may be prepaid in whole or in part at any time
after January 1, 1999, upon sixty (60) days' written notice by the Company to
the Holder. The Holder shall be permitted to convert this Note at any time prior
to the date of prepayment set forth in such notice.

         5. REDEMPTION AT THE OPTION OF HOLDER. If the shares of the Common
Stock into which this Note are convertible are not registered for resale by the
Holder under the Securities Act of 1933, as amended, prior to January 1, 1999,
Holder shall thereafter have the right to require the Company to redeem this
Note for cash upon ten (10) days' written notice by Holder to the Company at any
time prior to the date such registration becomes effective.

         6. RESERVATION OF SHARES. The Company covenants and agrees that, during
the period within which the conversion rights contained in this Note may be
exercised, the Company will at all times have authorized and reserved, solely
for the purpose of such possible conversion, out of its authorized by unissued
shares, a sufficient number of shares of its Common Stock (and such other
securities, if any, which become issuable upon conversion hereof by reason of
the antidilution provisions of this Note) to provide for the exercise in full of
the conversion rights contained in this Note.

         7. LOST DOCUMENTS. Upon receipt by the Company of evidence satisfactory
to it of the loss, theft, destruction or mutilation of this Note or any Note
exchanged for it, and (in the case of loss, theft or destruction) of indemnity
reasonably satisfactory to it, and upon reimbursement to the Company of all
reasonable expenses incidental thereto, and upon surrender and cancellation of
such Note, if mutilated, the Company will make and deliver in lieu of such a
Note a new Note of like tenor and unpaid principal amount and dated as of the
original date of the Note.

         8.  MISCELLANEOUS.

         (a) PARTIES IN INTEREST. All covenants, agreements and undertakings in
this Note by and on behalf of the Company shall bind and inure to the benefit of
the successors and assigns of the Company and the permitted successors and
assigns of the Holder whether so expressed or not.

         (b) NOTICES. All notices, requests, consents and demands given or made
pursuant to the provisions of this Note shall be made to the Company or to the
holder of this Note, as the case may be, by first class certified or registered
mail, post prepaid, or by hand delivery, in each case addressed

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as follows: (i) If to the Company, at the address of the Company set forth in
the first paragraph of this Note, and (ii) if to the holder of this Note, at the
address for such holder set forth on the Note Register of the Company maintained
for such purpose.

         (c) CONSTRUCTION. The Company, for itself and its successors and
assigns, expressly waives presentment for payment, demand, protest and notice of
demand, notice of dishonor and notice of nonpayment and all other notices not
specifically provided for in this Note.

         (d) COSTS OF COLLECTION; APPLICATION OF PAYMENTS. In the event that
this Note shall at any time after maturity be placed with an attorney for
collection, then the Company agrees to pay, in addition to the entire unpaid
principal balance and interest due hereunder, all collection costs, including
attorneys' fees and expenses, incurred by the Holder in collecting the
indebtedness due hereunder. All payments made hereunder prior to an Event of
Default shall first be applied to interest and then to principal; and all
payments made hereunder after an Event of Default shall first be applied to the
above-referenced costs of collection, then to interest and then to principal.

         (e) GOVERNING LAW; JURISDICTION AND VENUE. THIS NOTE SHALL BE INTER
PRETED, AND THE RIGHTS AND LIABILITIES OF THE COMPANY AND THE HOLDER DETERMINED,
IN ACCORDANCE WITH THE INTERNAL LAWS (AS OPPOSED TO CONFLICTS OF LAW PROVISIONS)
OF THE STATE OF FLORIDA. AS PART OF THE CONSIDERATION FOR NEW VALUE THIS DAY
RECEIVED, THE COMPANY HEREBY CONSENTS TO THE JURISDICTION OF ANY STATE OR
FEDERAL COURT LOCATED WITHIN DADE COUNTY, STATE OF FLORIDA, AND CONSENTS THAT
ALL SERVICE OF PROCESS BE MADE AT THE ADDRESS STATED IN, AND PURSUANT TO THE
TERMS OF, SECTION 8 ABOVE. THE COMPANY WAIVES ANY OBJECTION WHICH THE COMPANY
MAY HAVE BASED ON LACK OF JURISDICTION OR IMPROPER VENUE OR FORUM NON CONVENIENS
TO ANY SUIT OR PROCEEDING INSTITUTED BY THE HOLDER OF THIS NOTE IN ANY STATE OR
FEDERAL COURT LOCATED WITHIN DADE COUNTY, FLORIDA AND CONSENTS TO THE GRANTING
OF SUCH LEGAL OR EQUITABLE RELIEF AS IS DEEMED APPROPRIATE BY THE COURT. NOTHING
HEREIN SHALL AFFECT THE RIGHT OF THE HOLDER TO SERVE LEGAL PROCESS IN ANY OTHER
MANNER PERMITTED BY LAW OR AFFECT THE RIGHT OF THE HOLDER TO BRING ANY ACTION OR
PROCEEDING AGAINST THE COMPANY OR ITS PROPERTY IN THE COURTS OF ANY OTHER
JURISDICTION WHICH HAS JURISDICTION OVER THE COMPANY OR ITS PROPERTY.

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         (f) SECTION HEADINGS. The section headings contained in this Note are
for convenience of reference only and shall not affect the meaning or
interpretation of this Note.

         IN WITNESS WHEREOF, this Note has been executed and delivered on the
date first specified above by the duly authorized representative of the Company.

                                        U.S. DIAGNOSTIC INC.

                                        By:_______________________________

                                           _____________________,_________




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                                                              EXHIBIT A



                              NOTICE OF CONVERSION

         The undersigned hereby irrevocably exercises the option to convert this
Note, or the portion below designated, into shares of Common Stock of U.S.
DIAGNOSTIC INC. in accordance with the terms of the Note, and directs that the
shares issuable and deliverable upon conversion, together with any check in
payment for fractional shares, be issued in the name of and delivered to the
undersigned registered Holder hereof, unless a different name has been indicated
below. If shares are to be issued in the name of a person other than the
undersigned, the undersigned will pay all transfer taxes payable with respect
thereto.

Portion of this Note
to be converted:                    $______________

If shares of Common Stock are to be issued and registered in the name of a
person other than the undersigned, please print the name and address, including
zip code, and social security or other taxpayer identification number of such
person below:

                                    ------------------
                                    ------------------
                                    ------------------

Your Name:        ________________________
                  (exactly as your name appears
                  on the face of this Note)

By:___________________________

Title:________________________

Date:_________________________

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