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                                                                   Exhibit 10.32


                          CONTINUING CORPORATE GUARANTY

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PRINCIPAL AMOUNT:          Four Hundred Thirty-Five thousand One Hundred Dollars
                           ($435,100.00)

DEBTOR:                    London Radiosurgical Centres, Ltd.
                           154 Harley Street
                           London
                           United Kingdom

GUARANTOR:                 Neurotechnologies International, Inc.
                           2540 Shelter Island Drive, Suite F
                           San Diego, CA  92106

CREDITOR:                  Mobile PET Systems, Inc.
                           2540 Shelter Island Drive, Suite F
                           San Diego, CA  92106

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         For valuable consideration, Guarantor unconditionally guarantees and
promises to pay Creditor, its successors or assigns, on demand in lawful U.S.
currency, all debt of Debtor to Creditor, including that debt in the amount
referred to above, as follows:

         1.       MAXIMUM LIABILITY. Guarantor's liability shall include all
debt and obligations owed by Debtor to Creditor, including (a) the Principal
Amount set forth above; (b) all extensions and advances of principal or other
sums to Debtor by Creditor (c) all interest owed by Debtor on the foregoing; (d)
all Creditor's costs, expenses and attorneys fees, including any on appeal, in
connection with the collection of the debt or the collection or sale of any
collateral, whether there is a lawsuit; and (e) all other sums and obligations
due to Creditor from Debtor. This limitation on liability is not a restriction
on the amount of the debt of Debtor to Creditor either in the aggregate or at
one time. If Creditor presently holds one or more guaranties from Guarantor of
the debt of Debtor, the rights of Creditor under all guaranties shall be
cumulative. Guarantor's liability will be the total of all sums due under all
unterminated guaranties.

         2.       DEBT. "DEBT" is used in its most comprehensive sense and
includes all advances, debts, obligations, judgments and liabilities of Debtor,
or any one or more of them, whenever made, incurred or created, whether
voluntarily or however arising, whether due, absolute, contingent, liquidated or
determined, whether Debtor may be liable individually, jointly with others,
primarily, secondarily or as Guarantor, whether recovery on such debt may be or
become barred by any statute of limitations, whether such debt may be or become
otherwise unenforceable and whether such debt arises from transactions which may
be voidable on account of infancy, insanity, ULTRA VIRES or otherwise.

         3.       NATURE OF GUARANTORS UNDERTAKING. Guarantor's liability shall
be open and continuous for so long as this Guaranty is in force. Guarantor
intends to guarantee at all times the performance of all obligations of Debtor
to Creditor referred to herein. Guarantor's liability will be enforceable
against both the separate and community property of Guarantor whether now owned
or hereafter acquired.

         4.       CREDITOR'S DEALING WITH DEBTOR. Guarantor authorizes Creditor
to deal with Debtor and Debtors sureties, endorsers and any other Guarantor(s),
in any manner in which Creditor sees fit in connection with any debt of Debtor
to Creditor, now or hereafter created, without any further consent or


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authorization from Guarantor. Creditor may make secured or unsecured loans to
Debtor, Creditor may extend the terms for payment, or alter the terms relating
to the manner of payment, of any debt of Debtor; release any collateral given to
Creditor by Debtor, with or without the substitution of new collateral; release
or agree not to sue Debtors sureties, endorsers or other Guarantor on any terms
it chooses; sue or fail to sue Debtor on any overdue debt or may realize or
neglect to realize on any collateral held in connection therewith; all of the
foregoing without the necessity of any notice to or consent from Guarantor and
all without affecting Guarantor's liability hereunder.

         5.       DURATION OF GUARANTY. This Guaranty will take effect when
received by Creditor, without the, necessity of any acceptance by Creditor, and
will continue in full force until such time as all debt and obligations of
Debtor to Creditor and all debt and obligations of Guarantor hereunder are paid
in full. This Guaranty shall bind Guarantors estate as to debt created both
before and after Guarantor's death or incapacity.

         6.       CREDITOR'S RIGHTS. Guarantor expressly waives presentment,
protest, demand or notice of any kind, including notice of nonpayment of any of
Debtor's debt or of any collateral thereto and notice of any action or inaction
on the part of Debtor, Creditor or any surety, endorser or other Guarantor. On
any default of Debtor on any obligation to Creditor, Creditor may, at its
option, demand and be entitled to payment from Guarantor of the full amount of
any part of the amount of Debtors debt to Creditor, and all sums due hereunder.
If Guarantor shall not pay the sum demanded to Creditor, Creditor may proceed
directly and at once against Guarantor to collect such sum without first
proceeding against Debtor, or any surety, endorser or other Guarantor and
without foreclosing on or selling or otherwise disposing of any collateral
Creditor may have as security for any of Debtors debt. Creditors failure to make
such demand at such time or so to proceed shall not relieve Guarantor of its
obligations hereunder or in any sense constitute a waiver. Creditor shall have
the right to demand and collect from Guarantor all or part of Debtors debt and
failure of Creditor at any time to demand from Guarantor or to proceed to
collect from Guarantor the full amount of Debtor's debt from Guarantor shall not
preclude Creditor from later demanding or proceeding to collect from Guarantor
any remaining debt of Debtor to Creditor covered by this Guaranty. In any action
or suit against Guarantor to enforce this Guaranty, Creditor shall be entitled
to recover from Guarantor, in addition to costs and disbursements allowed by
law, a reasonable amount for Creditors attorneys' fees in such action or suit of
appeal therefrom. Guarantor waives any applicable statute of limitations to the
fullest extent permitted by law. If payment is made by Debtor on a debt
guaranteed hereby and thereafter Creditor is forced to remit the amount of that
payment to the Debtors trustee in bankruptcy or similar person under any federal
or state bankruptcy law or law for the relief of debtors, the Debtor's debt
shall be considered unpaid for the purpose of enforcement of this Guaranty.
Guarantor waives any right to participate in any collateral, until all debt of
Debtor to Creditor shall have been paid in full.

                  6.1.     In addition to all liens on, and rights of setoff
against the moneys, securities or other property of Guarantor given to Creditor
by law, Creditor shall have a security interest in and a right of setoff against
all moneys, securities and other property of Guarantor now or hereafter in
Creditors possession, whether held in a general or special account or deposit,
or for safekeeping or otherwise. Every such security interest and right of
setoff may be exercised without demand on or notice to Guarantor. No security
interest or right of setoff shall be deemed to have been waived by any act or
conduct on Creditor's part, or by any neglect to exercise such right of setoff
or to enforce such security interest, or by any delay in so doing. Every right
of setoff and security interest shall continue in full force and effect until
such right of setoff or security interest is specifically waived or released by
an instrument in writing executed by Creditor.

                  6.2.     If any one or more of Debtors or Guarantor are
corporations or partnerships, it is not necessary for Creditor to inquire into
the powers of Debtors or Guarantor or the officers, directors,


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partners or agents acting or purporting to act on their behalf, and any debt
made or created in reliance on the professed exercise of such powers shall be
guaranteed hereunder.

         7.       SUBORDINATION. The debt of Debtor to Creditor, whether now
existing or hereafter created, shall be prior to any claim that Guarantor may
now have or later acquire against Debtor, whether Debtor becomes insolvent, and
Guarantor expressly subordinates any such claim Guarantor may have against
Debtor, on any account whatsoever, to any claim that Creditor may now or
hereafter have against debtor. Guarantor waives any defense arising by reason
son of any disability or other defense of Debtor or by reason of the cessation
of Debtors liability for any reason. Guarantor shall not have any right of
subrogation until all debt of Debtor to Creditor shall have been paid in full.
In the event of insolvency and consequent liquidation of the assets of Debtor,
through bankruptcy, an assignment for the benefit of creditors, voluntary
liquidation or otherwise, the assets of Debtor applicable to the payment of the
claims of both Creditor and Guarantor shall be paid to Creditor and shall be
first applied by Creditor to the debt of Debtor to Creditor. Guarantor hereby
assigns to Creditor all claims which it may have or acquire against Debtor or
any assignee or trustee in bankruptcy of Debtor.

         8.       ASSIGNMENT OF GUARANTY Assignment by Creditor of all or part
of the debt shall transfer to the assignee all benefits of this Guaranty as to
the portion of the debt assigned. This Guaranty shall remain in effect in favor
of the Creditor as to the portion of the debt not assigned.

         9.       GUARANTOR. "GUARANTOR" includes all persons executing this
Guaranty. The liability of all Guarantors shall be joint and several.

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         If any one or more provisions of this Agreement be determined to be
illegal or unenforceable, all other provisions shall nevertheless remain
effective. This Agreement shall inure to the benefit of and bind, as the case
may require, Creditor, its successors and assigns, including the assignees of
any credit guaranteed hereby, and Guarantees representatives, successors and
assigns.


 THE UNDERSIGNED SPECIFICALLY ACKNOWLEDGES READING ALL TERMS OF THIS CONTINUING
              CORPORATE GUARANTY AND RECEIPT OF A TRUE COPY OF IT.


"GUARANTOR"


/s/ Paul Crowe
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PAUL J. CROWE                                          DATED: July 1, 2000