EXHIBIT 10.17

                          AMENDMENT TO CALLABLE WARRANT

     This AMENDMENT TO CALLABLE  WARRANT  ("Amendment")  is made as of this 28th
day of April, 2004 by and between FONAR CORPORATION, a Delaware corporation (the
"Company"), and THE TAIL WIND FUND LTD. ("Holder").

                              W I T N E S S E T H:

     WHEREAS, pursuant to that certain Purchase Agreement ("Purchase Agreement")
dated as of May 24, 2001 by and between the Company and the Holder,  the Company
sold and  issued to the  Holder  on May 24,  2001,  among  other  securities,  a
callable warrant ("Initial  Callable Warrant") expiring May 24, 2004 to purchase
2,000,000  shares of the  Company's  Common  Stock,  par value $0.0001 per share
("Common Stock");

     WHEREAS,  pursuant to those certain First and Second Amendments to Callable
Warrant dated as of June 21, 2002 and August 15, 2002 by and between the Company
and the Holder,  the Holder  exercised the Initial  Callable Warrant in full and
the  Company  issued to the Holder on August  30,  2002 a new  callable  warrant
("Warrant")  expiring  August 30,  2005 to purchase  2,000,000  shares of Common
Stock,  which Warrant provides for adjustment of the Warrant Price and number of
unexercised  Warrant  Shares  remaining  under the Warrant due to  issuances  of
Common  Stock  by  the  Company  under  the  circumstances   described  therein;
capitalized  terms used herein and not otherwise  defined  herein shall have the
meanings ascribed thereto in the Warrant;

     WHEREAS, the 2,000,000 Warrant Shares initially underlying the Warrant were
registered for resale pursuant to a registration statement originally filed with
the SEC under the  Securities  Act of 1933, as amended  ("Securities  Act"),  on
October  22,  2002  and  declared  effective  November  1,  2002  ("Registration
Statement"); and

     WHEREAS,  the  parties  wish to amend the  Warrant  Price and the number of
unexercised  Warrant  Shares  remaining  under the Warrant in  exchange  for the
Holder exercising the Warrant under such new terms in full;

     NOW THEREFORE,  in consideration  of the foregoing  premises and the mutual
covenants  set  forth  in  this  Amendment,  and for  other  good  and  valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereto agree as follows:

     1.  Amendment.  Notwithstanding  anything  contained  in the  Warrant,  the
Warrant  Price  under the Warrant  shall equal $1.00 per share of the  Company's
Common Stock and the number of unexercised  Warrant Shares  remaining  under the
Warrant shall equal  3,000,000  Warrant Shares as of the date of this Amendment.
It is  understood  that the new Warrant  Price and  increased  number of Warrant
Shares reflect an agreement reached by the parties after discussions  concerning
the  effect  of  the  applicable  provisions  of  the  Warrant  relating  to the
adjustment  of the  number  and price of  Warrant  Shares,  and that  Holder has
previously  exercised its rights to purchase  400,000  Warrant  Shares under the
Warrant.  Consequently,  the Holder acknowledges that 1,400,000 of the 3,000,000
Warrant  Shares are not covered by the  Registration  Statement or otherwise yet
registered   under  the  Securities  Act,  and  Holder  agrees  to  accept  such
unregistered  1,400,000 Warrant Shares (the "Unregistered  Warrant Shares") upon
Holder's  exercise of the Warrant for all the remaining  Warrant Shares pursuant
to Section 2 of this  Amendment.  The  Company  represents  and  warrants to the
Holder that the 400,000 Warrant Shares  previously  issued were duly authorized,
validly issued,  fully paid and non-assessable  shares of Common Stock, free and
clear of any liens, claims and encumbrances,  and the Holder is not aware of any
claim  against or liability  of the Company  arising out of the issuance of such
400,000 Warrant Shares previously  issued.  The issuance and prices paid for the
400,000 Warrant Shares previously issued are ratified and approved by Holder and
the Company. In addition,  the Company shall have no liability to the Holder for
not  notifying  the Holder of any  adjustment  to the price or number of Warrant
Shares that may have resulted from past issuance of Common Stock by the Company,
whether under the terms of the Warrant, the Purchase Agreement, the Registration
Rights  Agreement  or  otherwise.  Under no  circumstances  shall the  number of
Warrant  Shares be  increased  or the price of the Warrant  Shares be lowered by
reason  of  any  provision  of  the  Warrant,  the  Purchase  Agreement  or  the
Registration Rights Agreement or otherwise beyond the number and price set forth
herein  (assuming all the Warrant Shares are issued  contemporaneously  with the
execution hereof,  otherwise the adjustment provisions contained in Section 9 of
the Warrant  shall apply for any stock split,  stock  dividends,  distributions,
stock issuances,  and similar events covered by such Section 9 which occur after
execution hereof).

     2.  Exercise.  The Holder  hereby  exercises  the Warrant,  pursuant to the
Warrant  Exercise Form attached  hereto,  for the  remaining  3,000,000  Warrant
Shares  underlying the Warrant at the $1.00 Warrant Price for an aggregate price
of $3,000,000.  Upon the delivery of said remaining  Warrant Shares to Holder in
accordance with Holder's written instructions,  the Company will have no further
obligation  to issue shares under the Warrant,  and the Warrant  shall be deemed
exercised in full. Holder shall pay such aggregate price by wire transfer to the
account  designated  by the Company  immediately  following  full  execution and
delivery of this Amendment. It is understood, however, that said shares will not
be issued and released to Holder until payment is received.

     3. Registration Rights.

     a) Prospectus Supplement. Within three (3) business days following the date
     hereof,  the Company,  at its sole cost and expense and in accordance  with
     the Securities  Act,  shall file a prospectus  supplement to the prospectus
     under the Registration  Statement  previously filed with the SEC,  covering
     the changes to the Warrant described herein.

     b) Registration Rights. The Company shall, at its sole cost and expense and
     in accordance with the Securities Act, use its best efforts (1) to promptly
     file and have  declared  effective a resale  registration  statement on the
     appropriate  form  under  the  Securities  Act  with the SEC  covering  the
     1,400,000  Unregistered  Warrant  Shares to be issued upon  exercise of the
     Warrant hereunder,  and (2) to keep such registration statement current and
     effective  until all such shares  covered  thereby are available for resale
     pursuant to Rule 144(k)  under the  Securities  Act, or until such  earlier
     date as all such shares covered thereby shall have been sold ("Registration
     Period"). All the terms and conditions of the Registration Rights Agreement
     dated  as of May 24,  2001  by and  between  the  Company  and  the  Holder
     ("Registration  Rights  Agreement"),  shall apply  mutatis  mutandis to the
     registration  of  such  Unregistered   Warrant  Shares  and  the  continued
     registration of Warrant Shares under the Registration Statement,  including
     without  limitation  the   indemnification   and  contribution   provisions
     contained therein, and all such terms are incorporated by reference herein,
     provided that (a) the  Registration  Date with respect to the  Unregistered
     Warrant  Shares shall mean the date which is six (6) months  following  the
     date  hereof,  (b) the  "Registration  Period"  with respect to the Warrant
     Shares registered under the Registration  Statement shall continue from the
     date hereof until all such shares covered  thereby are available for resale
     pursuant to Rule 144(k) under the Securities Act or until such earlier date
     as all such  shares  covered  thereby  shall  have been  sold,  and (c) the
     "Registration Period" with respect to the Unregistered Warrant Shares shall
     have the meaning set forth in the previous sentence.

     4. Condition Precedent.  This Amendment is being executed concurrently with
a First  Amendment to Purchase  Warrant  dated the date hereof,  which  Purchase
Warrant was issued pursuant to the Purchase  Agreement,  and this Amendment will
not be  effective  until  such  First  Amendment  to  Purchase  Warrant  is also
effective.


     5. Miscellaneous.

     (a) Full Force and Effect.  Except as otherwise  expressly provided herein,
each of the Purchase Agreement,  the Registration Rights Agreement, the Warrant,
the First and Second  Amendments to Callable  Warrant,  and the other agreements
and transactions  contemplated thereby shall remain in full force and effect, to
the extent they are presently in force,  provided,  however,  that to the extent
any provision  thereof is inconsistent  with any of the terms of this Amendment,
the provisions of this Amendment will apply.

     (b) Consent to Jurisdiction, Etc. Each of the Company and Holder agree that
any legal  action or  proceeding  relating  to or  arising  out of or under this
Amendment  may be  brought  in the state or  federal  courts in the State of New
York,  County of New York, and each party accepts with regard to any such action
or  proceeding  for  itself  and in  respect  to  its  property,  generally  and
unconditionally, the jurisdiction of the aforesaid courts. To the fullest extent
permitted by applicable law, each party hereby waives, and agrees not to assert,
by way of motion,  defense,  counterclaim or otherwise, in any such suit, action
or  proceeding  any  claim  that  (i)  it  is  not  personally  subject  to  the
jurisdiction  of any of the  above-named  courts by reason  of any  immunity  or
otherwise,  (ii) its properties  are exempt or immune from setoff,  execution or
attachment,  either  prior to judgment or in aid of execution or (iii) any suit,
action or proceeding so brought is in an inconvenient forum or that the venue of
the suit, action or proceeding is improper or that the subject matter hereof may
not be enforced in or by such courts.

     (c)  Authority.  Each party hereto  hereby  represents  and warrants to the
other party that the execution and delivery by such party of this Amendment, and
the performance by such party of its obligations  hereunder,  have been duly and
validly authorized by such party, with no other action on the part of such party
being necessary. This Amendment has been duly and validly executed and delivered
by such party and  constitutes  a legal,  valid and binding  obligation  of such
party enforceable against such party in accordance with its terms.

     (d)  Governing  Law. This  Amendment  shall be governed by and construed in
accordance with the internal laws of the State of New York.

     (e) Notices. All notices,  requests and other communications hereunder must
be in  writing  and will be deemed to have been  duly  given  only if  delivered
personally,  by courier or by  facsimile  transmission  or mailed  (first  class
postage prepaid) to the parties at the addresses or facsimile  numbers set forth
in the Purchase Agreement.

     (f)  Counterparts.  This  Amendment  may  be  executed  in  any  number  of
counterparts,  each of  which  will be  deemed  an  original,  but all of  which
together will  constitute  one and the same  instrument.  This  Amendment may be
executed by facsimile.

     (g) Further  Assurances.  Each party shall do and  perform,  or cause to be
done and  performed,  all such  further acts and things,  and shall  execute and
deliver all such other agreements,  certificates,  instruments and documents, as
the other  party may  reasonably  request  in order to carry out the  intent and
accomplish  the  purposes  of  this  Amendment  and  the   consummation  of  the
transactions contemplated hereby.

     (h)  Expenses.  Upon  execution  hereof the Company  shall pay to Tail Wind
Advisory & Management Ltd. the  non-accountable  sum of $10,000 as and for legal
and due diligence  expenses in  connection  with the  transactions  contemplated
hereby and by the amendment of the purchase  warrant  issued to the Holder under
the Purchase Agreement.

     (i) Assignment;  Successors. Neither Holder nor the Company may assign this
Agreement or its respective  rights or obligations  hereunder  without the prior
written consent of the other, which may not be unreasonably withheld or delayed.
This Amendment shall be binding upon the Company's successors.

                    *** Signatures Appear on the Next Page***



     IN WITNESS WHEREOF, each of the parties hereto has caused this Amendment to
be duly executed as of the date first written above.

                                      FONAR CORPORATION

                                      By:/s/Raymond V. Damadian, M.D., Pres.
                                               Raymond Damadian, M.D., President



                                      THE TAIL WIND FUND LTD.
                                      By:      TAIL WIND ADVISORY AND
                                               MANAGEMENT LTD., as
                                               investment manager


                                                By: /s/David Crook
                                                Name:    David Crook
                                                Title:   CEO



                                FONAR CORPORATION
                              WARRANT EXERCISE FORM

Fonar Corporation
110 Marcus Drive
Melville, New York 11747
Telephone:        (631) 694-2929
Fax:              (631) 249-3734
Attention:        President

     This  undersigned  hereby  irrevocably  elects  to  exercise  the  right of
purchase  represented  by the within  Warrant,  as  amended  on the date  hereof
("Warrant"),  for, and to purchase thereunder payment in the aggregate amount of
U.S.  $3,000,000,  by cash, wire transfer or certified check 3,000,000 shares of
Common  Stock*  ("Warrant  Shares")  provided  for therein,  and  requests  that
certificates for the Warrant Shares be issued as follows:

                Name: THE TAIL WIND FUND LTD.
                Address for shares to be sent:
                c/o Bishop Rosen & Co.
                100 Broadway, 16th Floor
                New York, New York 10005

     In lieu of delivering physical certificates representing the Warrant Shares
purchasable upon exercise of this Warrant, provided the Company's transfer agent
is  participating  in  the  Depository  Trust  Company  ("DTC")  Fast  Automated
Securities  Transfer ("FAST") program,  upon request of the Holder,  the Company
shall, if convenient,  cause its transfer agent to  electronically  transmit the
Warrant  Shares  issuable  upon  conversion or exercise to the  undersigned,  by
crediting  the account of the  undersigned's  prime  broker with DTC through its
Deposit Withdrawal Agent Commission ("DWAC") system.

Dated:  April  ___, 2004         Signature:  THE TAIL WIND FUND LTD.
                                             By:      TAIL WIND ADVISORY AND
                                             MANAGEMENT LTD., as
                                             investment manager

                                               By: _________________________
                                               Name:    David Crook
                                                        Title:   CEO
                                               Address: c/o Tail Wind Advisory
                                                            & Mgmt. Ltd.
                                               1 Regent Street, 1st Floor
                                               London SW1Y 4NS  England

     If  exercise  of the  Warrant is made by  surrender  of the Warrant and the
number of  shares  indicated  exceeds  the  maximum  number of shares to which a
holder is  entitled,  the  Company  will  issue  such  maximum  number of shares
purchasable  upon  exercise  of  the  Warrant  registered  in  the  name  of the
undersigned  Warrantholder or the undersigned's  Assignee as below indicated and
deliver same to the address stated below.