<PAGE>   1
                                                                   EXHIBIT 10.12


                           LOAN AND SECURITY AGREEMENT

               THIS LOAN AND SECURITY AGREEMENT (this "Agreement"), dated as of
October 1, 1998, is made between Advanced Medical Procedures LLC, a Florida
limited liability company ("Borrower") and ENDOcare, Inc., a Delaware
corporation ("Lender").

               Borrower and Lender hereby agree as follows:

               SECTION 1 Definitions; Interpretation.

               (a) All capitalized terms used in this Agreement and not
otherwise defined herein shall have the meanings assigned to them in the Note.
As used in this Agreement, the following terms shall have the following
meanings:

               "Affiliate" means any Person which, directly or indirectly,
controls, is controlled by or is under common control with another Person. For
purposes of the foregoing, "control," "controlled by" and "under common control
with" with respect to any Person shall mean the possession, directly or
indirectly, of the power to direct or cause the direction of the management and
policies of such Person, whether through the ownership of voting securities or
by contract or otherwise.

               "Business Day" means a day (i) other than Saturday or Sunday, and
(ii) on which commercial banks are open for business in Orange County,
California.

               "Collateral" has the meaning set forth in Section 3.

               "Collateral Documents" means the Guarantor Security Agreement,
this Agreement and any other agreement pursuant to which the Borrower, the
Guarantor or any other Person provides a Lien on its assets in favor of the
Lender and all filings, documents and agreements made or delivered pursuant
thereto.

               "Event of Default" has the meaning set forth in Section 9.

               "Guarantor" means Robert F. Byrnes, an individual.

               "Guarantor Security Agreement" means that certain Guarantor
Security Agreement, dated of even date herewith, by and between Lender and
Robert F. Byrnes as the same may be amended, modified or restated from time to
time after the date herewith.

               "Lien" means any mortgage, deed of trust, pledge, security
interest, assignment, deposit arrangement, charge or encumbrance, lien, or other
type of preferential arrangement.

               "Loan Documents" means this Agreement, the Note, the Guarantor
Security Agreement and all other certificates, documents, agreements and
instruments delivered to Lender under the Note or in connection with the
Obligations.

               "Material Adverse Effect" means any event, matter, condition or
circumstance which (i) has or would reasonably be expected to have a material
adverse effect on the business,

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properties, results of operations or condition (financial or otherwise) of the
Borrower, (ii) would materially impair the ability of the Borrower or any other
Person to perform or observe its obligations under or in respect of the Loan
Documents; or (iii) affects the legality, validity, binding effect or
enforceability of any of the Loan Documents or the perfection or priority of any
Loan granted to the Lender under any of the Collateral Documents.

               "Note" means that certain Promissory Note dated October 1, 1998
made by Borrower in favor of Lender, as amended, modified, renewed, extended or
replaced from time to time.

               "Obligations" means the indebtedness, liabilities and other
obligations of Borrower to Lender under or in connection with this Agreement,
the Note and the other Loan Documents, including, without limitation, all unpaid
principal of the Note, all interest accrued thereon, all fees and all other
amounts payable by Borrower to Lender thereunder or in connection therewith,
whether now existing or hereafter arising, and whether due or to become due,
absolute or contingent, liquidated or unliquidated, determined or undetermined.

               "Permitted Lien" means (i) any Lien in favor of Lender; (ii) any
Liens existing as of the date hereof and disclosed in writing to Lender; and
(iii) other Liens which arise in the ordinary course of business and do not
materially impair Borrower's ownership or use of the Collateral or the value
thereof.

               "Person" means an individual, corporation, partnership, joint
venture, trust, unincorporated organization, governmental agency or authority,
or any other entity of whatever nature.

               "Revolving Commitment" means, $250,000 or, where the context so
requires, the obligation of the Lender to make Revolving Loans up to such amount
on the terms and conditions set forth in this Agreement.

               "Subsidiary" means any corporation, association, partnership,
joint venture or other business entity of which more than 50% of the voting
stock or other equity interest is owned directly or indirectly by any Person or
one or more of the other Subsidiaries of such Person or a combination thereof.

               "UCC" means the Uniform Commercial Code as the same may, from
time to time, be in effect in the State of California; provided, however, in the
event that, by reason of mandatory provisions of law, any or all of the
attachment, perfection or priority of the security interest in any Collateral is
governed by the Uniform Commercial Code as in effect in a jurisdiction other
than the State of California, the term "UCC" shall mean the Uniform Commercial
Code as in effect in such other jurisdiction for purposes of the provisions
hereof relating to such attachment, perfection or priority and for purposes of
definitions related to such provisions.

               (b) Where applicable and except as otherwise defined herein,
terms used in this Agreement shall have the meanings assigned to them in the
UCC.


                                       2.
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               (c) In this Agreement, (i) the meaning of defined terms shall be
equally applicable to both the singular and plural forms of the terms defined;
and (ii) the captions and headings are for convenience of reference only and
shall not affect the construction of this Agreement.

               SECTION 2 The Revolving Loans.

               (a) The Revolving Loans. Lender agrees, on the terms and
conditions hereinafter set forth, to make revolving loans (each a "Revolving
Loan" and, collectively, the "Revolving Loans") to the Lender from time to time
on any Business Day during the period from October 1, 1998 until September 30,
2000 (the "Revolving Expiry Date"), not to exceed $50,000 per month and in an
aggregate principal amount up to but not exceeding at any time the outstanding
Revolving Commitment. The Borrower shall pay interest on the unpaid principal
amount of each Revolving Loan from the date of such Revolving Loan until such
principal amount shall be paid in full, at the rates set forth in the Note.

               (b) Borrowing Procedure. Each Revolving Loan shall be made upon
written notice from the Borrower to the Lender, which notice shall be received
by the Lender not later than 10:00 A.M. (California time) at least three (3)
Business Days prior to the proposed borrowing date. Each such notice shall
specify the proposed date of the borrowing (which shall be a Business Day), the
amount of the borrowing and payment instructions with respect to the funds to be
made available to the Borrower. Upon fulfillment of the applicable conditions
set forth in subsection 2(e) below, the Lender shall make the Revolving Loan
available to the Borrower in same day funds, or such other funds as shall
separately be agreed upon by the Borrower and the Lender, in accordance with the
payment instructions provided to the Lender.

               (c) Evidence of Indebtedness. As additional evidence of the
Indebtedness of the Borrower to the Lender resulting from the Revolving Loans
made by the Lender, the Borrower shall execute and deliver to the Lender the
Note, dated of even date herewith, setting forth the Revolving Commitment as the
maximum principal amount thereof.

               (d) Repayment. The Borrower shall repay to the Lender in full the
aggregate Principal Amount, together with all accrued and unpaid interest
thereon, according to the terms set forth in the Note.

               (e) Conditions Precedent. The obligation of Lender to make each
Revolving Loan shall be subject to the satisfaction of each of the following
conditions precedent:

               (i) On and as of the date of such Revolving Loan, there shall
have occurred no Material Adverse Effect since the date of the most recent
borrowing.

               (ii) On the date of such Revolving Loan, both before and after
giving effect thereto and to the application of proceeds therefrom, (i) no Event
of Default shall have occurred and be continuing or shall result from the making
of such Revolving Loan and (ii) the representations and warranties contained in
Section 5 of this Agreement shall be true, correct and complete on and as of the
date of such Revolving Loan as though made on and as of such date. The giving of
any notice of borrowing and the acceptance by the Borrower of the proceeds of


                                       3.
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each Revolving Loan made following the date hereof shall be deemed a
certification to the Lender that on and as of the date of such Revolving Loan
such statements are true.

               SECTION 3 Security Interest.

               (a) As security for the payment and performance of the
Obligations, Borrower hereby pledges, assigns, transfers, hypothecates and sets
over to Lender, and hereby grants to Lender a security interest in, all of
Borrower's right, title and interest in, to and under the following property,
wherever located and whether now existing or owned or hereafter acquired or
arising (collectively, the "Collateral"):

               (i) all accounts, accounts receivable, contract rights, rights to
payment, chattel paper, letters of credit, documents, securities, money and
instruments, and investment property, whether held directly or through a
securities intermediary, and other obligations of any kind owed to Borrower,
however evidenced;

               (ii) all deposits and deposit accounts with any bank, savings and
loan association, credit union or like organization, and all funds and amounts
therein, and whether or not held in trust, or in custody or safekeeping, or
otherwise restricted or designated for a particular purpose;

               (iii) all inventory, including, without limitation, all
materials, raw materials, parts, components, work in progress, finished goods,
merchandise, supplies, and all other goods which are held for sale, lease or
other disposition or furnished under contracts of service or consumed in
Borrower's business, including, without limitation, those held for display or
demonstration or out on lease or consignment;

               (iv) all equipment, including, without limitation, all machinery,
furniture, furnishings, fixtures, trade fixtures, tools, parts and supplies,
automobiles, trucks, tractors and other vehicles, appliances, computer and other
electronic data processing equipment and other office equipment, computer
programs and related data processing software, and all additions, substitutions,
replacements, parts, accessories, and accessions to and for the foregoing;

               (v) all general intangibles and other personal property of
Borrower, including, without limitation, (A) all tax and other refunds, rebates
or credits of every kind and nature to which Borrower is now or hereafter may
become entitled; (B) all intellectual property and all rights therein of any
type or description, including, without limitation, all inventions and
discoveries, patents and patent applications, copyrights and applications for
copyright (together with the underlying works of authorship) whether or not
registered, together with any renewals and extensions thereof, trademarks,
service marks and trade names, and applications for registration of such
trademarks, service marks and trade names, trade secrets, trade dress, trade
styles, logos, other source of business identifiers, mask-works, mask-work
registrations, mask-work applications, software, confidential and proprietary
information, customer lists, other license rights, advertising materials,
operating manuals, methods, processes, know-how, algorithms, formulae,
databases, quality control procedures, product, service and technical
specifications, operating, production and quality control manuals, sales
literature, drawings, specifications, blue prints, descriptions, inventions,
name plates and catalogs, and the entire


                                       4.
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goodwill of or associated with the businesses now or hereafter conducted by
Borrower connected with and symbolized by any of the aforementioned properties
and assets, and all licenses relating to any of the foregoing, all reissuances,
continuations and continuations-in-part of the foregoing, all other rights
derived from or associated with the foregoing, including the right to sue and
recover for past infringement, and all income and royalties with respect
thereto; (C) all good will, choses in action and causes of action; (D) all
interests in limited and general partnerships and limited liability companies;
and (E) all indemnity agreements, guaranties, insurance policies, insurance
claims, and other contractual, equitable and legal rights of whatever kind or
nature;

               (vi) all books, records and other written, electronic or other
documentation in whatever form maintained by or for Borrower in connection with
the ownership of its assets or the conduct of its business or evidencing or
containing information relating to the Collateral; and

               (vii) all products and proceeds, including insurance proceeds, of
any and all of the foregoing.

               (b) Anything herein to the contrary notwithstanding, (i) Borrower
shall remain liable under any contracts, agreements and other documents included
in the Collateral, to the extent set forth therein, to perform all of its duties
and obligations thereunder to the same extent as if this Agreement had not been
executed, (ii) the exercise by Lender of any of the rights hereunder shall not
release Borrower from any of its duties or obligations under such contracts,
agreements and other documents included in the Collateral, and (iii) Lender
shall not have any obligation or liability under any contracts, agreements and
other documents included in the Collateral by reason of this Agreement, nor
shall Lender be obligated to perform any of the obligations or duties of
Borrower thereunder or to take any action to collect or enforce any such
contract, agreement or other document included in the Collateral hereunder.

               (c) This Agreement shall create a continuing security interest in
the Collateral which shall remain in effect until terminated in accordance with
Section 20 hereof.

               SECTION 4 Financing Statements, Etc. Borrower shall execute and
deliver to Lender concurrently with the execution of this Agreement, and at any
time and from time to time thereafter, all financing statements, assignments,
continuation financing statements, termination statements, account control
agreements, and other documents and instruments, in form reasonably satisfactory
to Lender, and take all other action, as Lender may reasonably request, to
perfect and continue perfected, maintain the priority of or provide notice of
the security interest of Lender in the Collateral and to accomplish the purposes
of this Agreement.

               SECTION 5 Representations and Warranties. Borrower represents and
warrants to Lender that:

               (a) Borrower is a corporation duly organized, validly existing
and in good standing under the law of the jurisdiction of its incorporation and
has all requisite power and authority to execute, deliver and perform its
obligations under this Agreement.

               (b) The execution, delivery and performance by Borrower of this
Agreement have been duly authorized by all necessary corporate action of
Borrower, and this Agreement


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constitutes the legal, valid and binding obligation of Borrower, enforceable
against Borrower in accordance with its terms.

               (c) No authorization, consent, approval, license, exemption of,
or filing or registration with, any governmental authority or agency, or
approval or consent of any other Person, is required for the due execution,
delivery or performance by Borrower of this Agreement.

               (d) Borrower's chief executive office and principal place of
business is located at the address set forth in Schedule 1; all other locations
where Borrower conducts business or Collateral is kept are set forth in Schedule
1; and all trade names and fictitious names under which Borrower at any time in
the past has conducted or presently conducts its business operations are set
forth in Schedule 1 or Schedule 2.

               (e) Borrower is the sole and complete owner of the Collateral,
free from any Lien other than Permitted Liens.

               (f) All of Borrower's U.S. and foreign patents and patent
applications, copyrights (whether or not registered), applications for
copyright, trademarks, service marks and trade names (whether registered or
unregistered), and applications for registration of such trademarks, service
marks and trade names, are set forth in Schedule 2.

               SECTION 6 Covenants. So long as any of the Obligations remain
unsatisfied, Borrower agrees that:

               (a) The Borrower will use the proceeds of the Revolving Loans
solely for working capital and other general corporate purposes.

               (b) The Borrower will not, and will not permit any of its
Subsidiaries to, merge with or consolidate into, or acquire all or substantially
all of the assets of, any Person, or sell, transfer, lease or otherwise dispose
of (whether in one transaction or a series of transactions) all or substantially
all of its assets, except that any of the Borrower's wholly owned Subsidiaries
may merge with, consolidate into or transfer all or substantially all of its
assets to another of the Borrower's wholly owned Subsidiaries or to the Borrower
and in connection therewith such Subsidiary may be liquidated or dissolved.

               (c) The Borrower will not declare or pay any dividends in respect
of the Borrower's capital stock, or purchase, redeem, retire or otherwise
acquire for value any of its capital stock now or hereafter outstanding, return
any capital to its shareholders as such, or make any distribution of assets to
its shareholders as such, or permit any of its Subsidiaries to purchase, redeem,
retire, or otherwise acquire for value any stock of the Borrower, except that
the Borrower may: (A) declare and deliver dividends and distributions payable
only in common stock of the Borrower and (B) purchase, redeem, retire, or
otherwise acquire shares of its capital stock with the proceeds received from a
substantially concurrent issue of new shares of its capital stock.

               (d) The Borrower will not, and will not permit any of its
Subsidiaries to, purchase or otherwise acquire the capital stock, assets
(constituting a business unit), obligations


                                       6.
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or other securities of or any interest in any Person, or otherwise extend any
credit to or make any additional investments in any Person, other than in
connection with: (i) extensions of credit in the nature of accounts receivable
or notes receivable arising from the sales of goods or services in the ordinary
course of business and (ii) short term, investment grade money market
instruments, in accordance with the Borrower's usual and customary treasury
management policies.

               (e) The Borrower will not, and will not permit any of its
Subsidiaries to, enter into any transaction, including the purchase, sale or
exchange of property or the rendering of any services, with any Affiliate, any
officer or director thereof or any Person which beneficially owns or holds 5% or
more of the equity securities, or 5% or more of the equity interest, thereof (a
"Related Party"), or enter into, assume or suffer to exist, or permit any
Subsidiary to enter into, assume or suffer to exist, any employment or
consulting contract with any Related Party, except a transaction or contract
which is in the ordinary course of the Borrower's or Subsidiary's business and
which is upon fair and reasonable terms not less favorable to the Borrower or
such Subsidiary than it would obtain in a comparable arm's length transaction
with a Person not a Related Party.

               (f) Borrower shall appear in and defend any action, suit or
proceeding which may affect to a material extent its title to, or right or
interest in, or Lender's right or interest in, the Collateral, and shall do and
perform all reasonable acts that may be necessary and appropriate to maintain,
preserve and protect the Collateral.

               (g) Borrower shall comply in all material respects with all laws,
regulations and ordinances, and all policies of insurance, relating in a
material way to the possession, operation, maintenance and control of the
Collateral.

               (h) Borrower shall give prompt written notice to Lender (and in
any event not later than 30 days following any change described below in this
subsection) of: (i) any change in the location of Borrower's chief executive
office or principal place of business, (ii) any change in the locations set
forth in Schedule 1; (iii) any change in its name, (iv) any changes in,
additions to or other modifications of its trade names and trade styles set
forth in Schedule 1 or Schedule 2, and (v) any changes in its identity or
structure in any manner which might make any financing statement filed hereunder
incorrect or misleading.

               (i) Borrower shall carry and maintain in full force and effect,
at its own expense and with financially sound and reputable insurance companies,
insurance with respect to the Collateral in such amounts, with such deductibles
and covering such risks as is customarily carried by companies engaged in the
same or similar businesses and owning similar properties in the localities where
Borrower operates. Upon the request of Lender, Borrower shall furnish Lender
from time to time with full information as to the insurance carried by it and,
if so requested, copies of all such insurance policies. Borrower shall also
furnish to Lender from time to time upon the request of Lender a certificate of
Borrower's insurance broker or other insurance specialist stating that all
premiums then due on the policies relating to insurance on the Collateral have
been paid and that such policies are in full force and effect. Receipt of notice
of termination or cancellation of any such insurance policies or reduction of
coverages or amounts thereunder shall entitle Lender to renew any such policies,
cause the coverages and amounts thereof to be maintained at levels required
pursuant to the first sentence of this subsection (d) or


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otherwise to obtain similar insurance in place of such policies, in each case at
the expense of Borrower.

               (j) Borrower shall keep separate, accurate and complete books and
records with respect to the Collateral, disclosing Lender's security interest
hereunder.

               (k) Borrower shall not surrender or lose possession of (other
than to Lender), sell, lease, rent, or otherwise dispose of or transfer any of
the Collateral or any right or interest therein, except in the ordinary course
of business; provided that no such disposition or transfer of Collateral
consisting of investment property or instruments shall be permitted while any
Event of Default exists.

               (l) Borrower shall keep the Collateral free of all Liens except
Permitted Liens.

               (m) Borrower shall pay and discharge all taxes, fees, assessments
and governmental charges or levies imposed upon it with respect to the
Collateral prior to the date on which penalties attach thereto, except to the
extent such taxes, fees, assessments or governmental charges or levies are being
contested in good faith by appropriate proceedings.

               (n) Borrower shall maintain and preserve its corporate existence,
its rights to transact business and all other rights, franchises and privileges
necessary or desirable in the normal course of its business and operations and
the ownership of the Collateral, except in connection with any transactions
expressly permitted by the Note.

               (o) Upon the request of Lender, Borrower shall (i) immediately
deliver to Lender, or an agent designated by it, appropriately endorsed or
accompanied by appropriate instruments of transfer or assignment, all documents
and instruments, all certificated securities with respect to any investment
property, all letters of credit and all accounts and other rights to payment at
any time evidenced by promissory notes, trade acceptances or other instruments,
(ii) cause any securities intermediaries to show on their books that Lender is
the entitlement holder with respect to any investment property, and/or obtain
account control agreements in favor of Lender from such securities
intermediaries, in form and substance satisfactory to Lender, with respect to
any investment property, as requested by Lender, (iii) mark all documents and
chattel paper with such legends as Lender shall reasonably specify, and (iv)
obtain consents from any letter of credit issuers with respect to the assignment
to Lender of any letter of credit proceeds.

               (p) Borrower shall at any reasonable time and from time to time
permit Lender or any of its agents or representatives to visit the premises of
Borrower and inspect the Collateral and to examine and make copies of and
abstracts from the records and books of account of Borrower.

               (q) Borrower shall (i) notify Lender of any material claim made
or asserted against the Collateral by any Person and of any change in the
composition of the Collateral or other event which could materially adversely
affect the value of the Collateral or Lender's Lien thereon; (ii) furnish to
Lender such statements and schedules further identifying and describing the
Collateral and such other reports and other information in connection with the
Collateral as


                                       8.
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Lender may reasonably request, all in reasonable detail; and (iii) upon
reasonable request of Lender make such demands and requests for information and
reports as Borrower is entitled to make in respect of the Collateral.

               (r) If and when Borrower shall obtain rights to any new patents,
trademarks, service marks, trade names or copyrights, or otherwise acquire or
become entitled to the benefit of, or apply for registration of, any of the
foregoing, Borrower (i) shall promptly notify Lender thereof and (ii) hereby
authorizes Lender to modify, amend, or supplement Schedule 2 and from time to
time to include any of the foregoing and make all necessary or appropriate
filings with respect thereto.

               (s) Borrower shall give Lender immediate notice of the
establishment of any new deposit account and any new securities account with
respect to any investment property.

               SECTION 7 Collection of Accounts. Until Lender exercises its
rights hereunder to collect the accounts and other rights to payment, Borrower
shall endeavor in the first instance diligently to collect all amounts due or to
become due on or with respect to the accounts and other rights to payment. At
the request of Lender, upon the occurrence and during the continuance of any
Event of Default, all remittances received by Borrower shall be held in trust
for Lender and, in accordance with Lender's instructions, remitted to Lender or
deposited to an account of Lender in the form received (with any necessary
endorsements or instruments of assignment or transfer).

               SECTION 8 Authorization; Lender Appointed Attorney-in-Fact.
Lender shall have the right to, in the name of Borrower, or in the name of
Lender or otherwise, upon notice to but without the requirement of assent by
Borrower, and Borrower hereby constitutes and appoints Lender (and any of
Lender's officers, employees or agents designated by Lender) as Borrower's true
and lawful attorney-in-fact, with full power and authority to: (i) sign any of
the financing statements and other documents and instruments which must be
executed or filed to perfect or continue perfected, maintain the priority of or
provide notice of Lender's security interest in the Collateral (including any
notices to or agreements with any securities intermediary); (ii) assert, adjust,
sue for, compromise or release any claims under any policies of insurance; and
(iii) execute any and all such other documents and instruments, and do any and
all acts and things for and on behalf of Borrower, which Lender may deem
reasonably necessary or advisable to maintain, protect, realize upon and
preserve the Collateral and Lender's security interest therein and to accomplish
the purposes of this Agreement. Lender agrees that, except upon and during the
continuance of an Event of Default, it shall not exercise the power of attorney,
or any rights granted to Lender, pursuant to clauses (ii) and (iii). The
foregoing power of attorney is coupled with an interest and irrevocable so long
as the Obligations have not been paid and performed in full. Borrower hereby
ratifies, to the extent permitted by law, all that Lender shall lawfully and in
good faith do or cause to be done by virtue of and in compliance with this
Section 8.

               SECTION 9 Events of Default. Any of the following events which
shall occur and be continuing shall constitute an "Event of Default":


                                       9.
<PAGE>   10

               (a) Borrower shall fail to pay when due any amount of principal
of or interest on the Note or other amount payable hereunder or under the Note
or in respect of the Obligations.

               (b) Any representation or warranty by Borrower under or in
connection with this Agreement or the Note shall prove to have been incorrect in
any material respect when made or deemed made.

               (c) Borrower shall fail to perform or observe in any material
respect any other term, covenant or agreement contained in this Agreement or the
Note on its part to be performed or observed and any such failure shall remain
unremedied for a period of five (5) days from the occurrence thereof; or any
"Event of Default" as defined in the Note shall have occurred.

               (d) Borrower shall admit in writing its inability to, or shall
fail generally or be generally unable to, pay its debts (including its payrolls)
as such debts become due, or shall make a general assignment for the benefit of
creditors; or Borrower shall file a voluntary petition in bankruptcy or a
petition or answer seeking reorganization, to effect a plan or other arrangement
with creditors or any other relief under the Bankruptcy Reform Act of 1978, as
amended or recodified from time to time (the "Bankruptcy Code") or under any
other state or federal law relating to bankruptcy or reorganization granting
relief to Borrowers, whether now or hereafter in effect, or shall file an answer
admitting the jurisdiction of the court and the material allegations of any
involuntary petition filed against Borrower pursuant to the Bankruptcy Code or
any such other state or federal law; or Borrower shall be adjudicated a
bankrupt, or shall make an assignment for the benefit of creditors, or shall
apply for or consent to the appointment of any custodian, receiver or trustee
for all or any substantial part of Borrower's property, or shall take any action
to authorize any of the actions set forth above in this paragraph; or an
involuntary petition seeking any of the relief specified in this paragraph shall
be filed against Borrower; or any order for relief shall be entered against
Borrower in any involuntary proceeding under the Bankruptcy Code or any such
other state or federal law referred to in this subsection (d).

               (e) Borrower shall (i) liquidate, wind up or dissolve (or suffer
any liquidation, wind-up or dissolution), except to the extent expressly
permitted by the Note, (ii) suspend its operations other than in the ordinary
course of business or (iii) take any corporate action to authorize any of the
actions or events set forth above in this subsection (e).

               (f) Any material impairment in the value of the Collateral or the
priority of Lender's Lien hereunder.

               (g) Any levy upon, seizure or attachment of any of the
Collateral.

               (h) Any loss, theft or substantial damage to, or destruction of,
any material portion of the Collateral (unless within five (5) days after the
occurrence of any such event, Borrower furnishes to Lender evidence satisfactory
to Lender that the amount of any such loss, theft, damage to or destruction of
the Collateral is fully insured under policies naming Lender as an additional
named insured or loss payee).

               (i) The Guarantor Security Agreement and any documents executed
pursuant thereto shall for any reason be revoked or invalidated, or otherwise
cease to be in full force and


                                      10.
<PAGE>   11

effect, or the Pledgor or any other Person shall contest in any manner the
validity or enforceability thereof or deny that it has any further liability or
obligation thereunder.

               (j) The Domestic Distributor Agreement by and between Borrower
and Lender dated October 1, 1998, as amended, shall for any reason be
terminated, revoked or invalidated, or otherwise cease to be in full force and
effect, or any Person shall contest in any manner the validity or enforceability
thereof or deny that it has any further liability or obligation thereunder.

               SECTION 10 Remedies.

               (a) Upon the occurrence and continuance of any Event of Default,
Lender may declare any of the Obligations to be immediately due and payable and
shall have, in addition to all other rights and remedies granted to it in this
Agreement, the Note or any other Document, all rights and remedies of a Lender
under the UCC and other applicable laws. Without limiting the generality of the
foregoing, Lender may sell, resell, lease, use, assign, license, sublicense,
transfer or otherwise dispose of any or all of the Collateral in its then
condition or following any commercially reasonable preparation or processing
(utilizing in connection therewith any of Borrower's assets, without charge or
liability to Lender therefor) at public or private sale, by one or more
contracts, in one or more parcels, at the same or different times, for cash or
credit, or for future delivery without assumption of any credit risk, all as
Lender deems advisable; provided, however, that Borrower shall be credited with
the net proceeds of sale only when such proceeds are finally collected by
Lender. Lender shall have the right upon any such public sale, and, to the
extent permitted by law, upon any such private sale, to purchase the whole or
any part of the Collateral so sold, free of any right or equity of redemption,
which right or equity of redemption Borrower hereby releases, to the extent
permitted by law. Borrower hereby agrees that the sending of notice by ordinary
mail, postage prepaid, to the address of Borrower set forth herein, of the place
and time of any public sale or of the time after which any private sale or other
intended disposition is to be made, shall be deemed reasonable notice thereof if
such notice is sent ten days prior to the date of such sale or other disposition
or the date on or after which such sale or other disposition may occur, provided
that Lender may provide Borrower shorter notice or no notice, to the extent
permitted by the UCC or other applicable law.

               (b) For the purpose of enabling Lender to exercise its rights and
remedies under this Section 10 or otherwise in connection with this Agreement,
Borrower hereby grants to Lender an irrevocable, non-exclusive and assignable
license (exercisable without payment or royalty or other compensation to
Borrower) to use, license or sublicense any intellectual property Collateral.

               (c) The cash proceeds actually received from the sale or other
disposition or collection of Collateral, and any other amounts received in
respect of the Collateral the application of which is not otherwise provided for
herein, shall be applied first, to the payment of the reasonable costs and
expenses of Lender in exercising or enforcing its rights hereunder and in
collecting or attempting to collect any of the Collateral, and to the payment of
all other amounts payable to Lender pursuant to Section 14 hereof; and second,
to the payment of the Obligations. Any surplus thereof which exists after
payment and performance in full of the Obligations shall


                                      11.
<PAGE>   12

be promptly paid over to Borrower or otherwise disposed of in accordance with
the UCC or other applicable law. Borrower shall remain liable to Lender for any
deficiency which exists after any sale or other disposition or collection of
Collateral.

               SECTION 11 Certain Waivers. Borrower waives, to the fullest
extent permitted by law, (i) any right of redemption with respect to the
Collateral, whether before or after sale hereunder, and all rights, if any, of
marshalling of the Collateral or other collateral or security for the
Obligations; (ii) any right to require Lender (A) to proceed against any Person,
(B) to exhaust any other collateral or security for any of the Obligations, (C)
to pursue any remedy in Lender's power, or (D) to make or give any presentments,
demands for performance, notices of nonperformance, protests, notices of
protests or notices of dishonor in connection with any of the Collateral; and
(iii) all claims, damages, and demands against Lender arising out of the
repossession, retention, sale or application of the proceeds of any sale of the
Collateral.

               SECTION 12 Notices. All notices or other communications hereunder
shall be in writing and mailed, sent or delivered to the respective parties
hereto at or to their respective addresses or facsimile numbers set forth below
their names on the signature pages hereof, or at or to such other address or
facsimile number as shall be designated by any party in a written notice to the
other parties hereto. All such notices and other communications shall be
effective (i) if delivered by hand, when delivered; (ii) if sent by mail, upon
the earlier of the date of receipt or five business days after deposit in the
mail, first class; and (iii) if sent by facsimile transmission, when sent.

               SECTION 13 No Waiver; Cumulative Remedies. No failure on the part
of Lender to exercise, and no delay in exercising, any right, remedy, power or
privilege hereunder shall operate as a waiver thereof, nor shall any single or
partial exercise of any such right, remedy, power or privilege preclude any
other or further exercise thereof or the exercise of any other right, remedy,
power or privilege. The rights and remedies under this Agreement are cumulative
and not exclusive of any rights, remedies, powers and privileges that may
otherwise be available to Lender.

               SECTION 14 Costs and Expenses.

               (a) Borrower agrees to pay on demand (i) one-half the reasonable
out-of-pocket costs and expenses of the Lender and any of its Affiliates, and
one-half the reasonable fees and disbursements of counsel to Lender, in
connection with the negotiation, preparation, execution, delivery and
administration of the Loan Documents and any amendments, modifications or
waivers of the terms thereof; (ii) one-half all audit, consulting, appraisal,
search, recording, filing and similar costs, fees and expenses incurred or
sustained by Lender or any of its Affiliates in connection with the Loan
Documents or the Collateral and (iii) all costs and expenses of Lender, and the
fees and disbursements of counsel, in connection with the enforcement or
attempted enforcement of, and preservation of any rights or interests under,
this Agreement and the Note, including in any out-of-court workout or other
refinancing or restructuring or in any bankruptcy case, and the protection, sale
or collection of, or other realization upon, any of the Collateral, including
all expenses of taking, collecting, holding, sorting, handling, preparing for
sale, selling, or the like, and other such expenses of sales and collections of
Collateral.


                                      12.
<PAGE>   13

               (b) Any amounts payable to Lender under this Section 14(b) or
otherwise under this Agreement if not paid upon demand shall bear interest from
the date of such demand until paid in full, at the rate of interest otherwise
applicable plus two percent (2%), but not to exceed the highest rate of interest
permitted by law.

               SECTION 15 Binding Effect. This Agreement shall be binding upon,
inure to the benefit of and be enforceable by Borrower, Lender and their
respective successors and assigns.

               SECTION 16 Governing Law. This Agreement shall be governed by,
and construed in accordance with, the law of the State of California, except as
required by mandatory provisions of law and to the extent the validity or
perfection of the security interests hereunder, or the remedies hereunder, in
respect of any Collateral are governed by the law of a jurisdiction other than
California.

               SECTION 17 Entire Agreement; Amendment. This Agreement contains
the entire agreement of the parties with respect to the subject matter hereof
and shall not be amended except by the written agreement of the parties.

               SECTION 18 Severability. Whenever possible, each provision of
this Agreement shall be interpreted in such manner as to be effective and valid
under all applicable laws and regulations. If, however, any provision of this
Agreement shall be prohibited by or invalid under any such law or regulation in
any jurisdiction, it shall, as to such jurisdiction, be deemed modified to
conform to the minimum requirements of such law or regulation, or, if for any
reason it is not deemed so modified, it shall be ineffective and invalid only to
the extent of such prohibition or invalidity without affecting the remaining
provisions of this Agreement, or the validity or effectiveness of such provision
in any other jurisdiction.

               SECTION 19 Counterparts. This Agreement may be executed in any
number of counterparts and by different parties hereto in separate counterparts,
each of which when so executed shall be deemed to be an original and all of
which taken together shall constitute but one and the same agreement.

               SECTION 20 Termination. Upon payment and performance in full of
all Obligations, this Agreement shall terminate and Lender shall promptly
execute and deliver to Borrower such documents and instruments reasonably
requested by Borrower as shall be necessary to evidence termination of all
security interests given by Borrower to Lender hereunder; provided, however,
that the obligations of Borrower under Section 14 hereof shall survive such
termination.


                                      13.
<PAGE>   14

        IN WITNESS WHEREOF, the parties hereto have duly executed this
Agreement, as of the date first above written.


                                        ADVANCED MEDICAL PROCEDURES


                                        By:      /s/ [Illegible]
                                              ----------------------------------
                                              Title:
                                                     ---------------------------


                                              ----------------------------------
                                              ----------------------------------
                                              ----------------------------------
                                        Attn:
                                              ----------------------------------
                                        Fax:
                                              ----------------------------------


                                        ENDOCARE, INC.


                                        By:      /s/ William R. Hughes
                                              ----------------------------------
                                              Title: Senior Vice President and
                                                     Chief Financial Officer


                                              ----------------------------------
                                              ----------------------------------
                                              ----------------------------------
                                        Attn: William R. Hughes
                                        Fax: (949) 597-0607



                                      14.
<PAGE>   15

                                   SCHEDULE 1
                       to the Loan and Security Agreement


1.      LOCATIONS OF CHIEF EXECUTIVE OFFICE AND OTHER LOCATIONS, INCLUDING OF
COLLATERAL

               a.      Chief Executive Office and Principal Place of Business:



               b.      Other locations where Borrower conducts business or
Collateral is kept:



2.      TRADE NAMES AND TRADE STYLES; OTHER CORPORATE, TRADE OR FICTITIOUS
NAMES, ETC.



                                      S-1.
<PAGE>   16

                                   SCHEDULE 2
                       to the Loan and Security Agreement


1.      PATENTS AND PATENT APPLICATIONS.



2.      COPYRIGHTS (REGISTERED AND UNREGISTERED) AND COPYRIGHT APPLICATIONS.



3.      TRADEMARKS, SERVICE MARKS AND TRADE NAMES AND TRADEMARK, SERVICE MARK
AND TRADE NAME APPLICATIONS.



                                      S-2.
<PAGE>   17

                            REVOLVING PROMISSORY NOTE


$250,000                                                  Dated: October 1, 1998

               FOR VALUE RECEIVED, the undersigned, Advanced Medical Procedures
LLC, a Florida limited liability company (the "Borrower"), HEREBY
UNCONDITIONALLY PROMISES TO PAY to the order of Endocare, Inc., a Delaware
corporation (the "Lender"), the principal sum of Two Hundred Fifty Thousand
Dollars ($250,000) or if less, the aggregate unpaid principal amount calculated
pursuant to Annex I hereto (the "Principal Amount"), together with accrued and
unpaid interest thereon through and including the Maturity Date (as defined
below) at the rate or rates and in the manner hereinafter provided.

               For the period commencing on the date hereof through and
including September 30, 2000 (the "Repayment Date"), this Note shall bear
interest on the Principal Amount from time to time outstanding at a rate per
annum equal to the Prime Rate plus one percent (1%), calculated without
compounding, and such interest shall be payable calendar quarterly in arrears,
on the last day of each calendar quarter occurring within such period. For the
period (the "Repayment Period") commencing on the Repayment Date through and
including September 30, 2001 (the "Maturity Date"), this Note shall bear
interest on the Principal Amount and any accrued but unpaid interest outstanding
as of the Repayment Date at a rate per annum equal to [nine and one-half percent
(9 1/2)]. All computations of interest shall be made on the basis of a year of
360 days for the actual number of days (including the first day but excluding
the last day) occurring in the period for which such interest is payable. Any
amounts payable to Lender under this Note if not paid upon demand shall bear
interest from the date of such demand until paid in full, at the rate of
interest otherwise applicable plus two percent (2%), but not to exceed the
highest rate of interest permitted by law.

               The unpaid balance of the Principal Amount shall be repayed by
Borrower to Lender in twelve (12) equal monthly installments on the last day of
each month commencing on the Repayment Date through the Maturity Date, together
with all accrued and unpaid interest thereon (as set forth below).

               All payments hereunder shall be made in lawful money of the
United States of America and in same day or immediately available funds, to the
Lender, at 7 Studebaker, Irvine, California 92618, or at such other place or to
such account as the Lender from time to time shall designate in a written notice
to the Borrower.

               Lender shall record the date and the amount of each Revolving
Loan made, each conversion to a different interest rate, the amount of principal
and interest due and payable from time to time hereunder, each payment thereof,
and the resulting unpaid principal balance hereof, in the Lender's internal
records, and any such recordation shall be rebuttable presumptive evidence of
the accuracy of the information so recorded; provided, however, that the
Lender's failure so to record shall not limit or otherwise affect the
obligations of the Borrower hereunder and under the Loan and Security Agreement
(as defined below) to repay the principal of and interest on the Revolving
Loans.

<PAGE>   18

               Whenever any payment hereunder shall be stated to be due, or
whenever any interest payment date or any other date specified hereunder would
otherwise occur, on a day other than a Business Day (as defined below), then
such payment shall be made, and such interest payment date or other date shall
occur, on the next succeeding Business Day, and such extension of time shall in
such case be included in the computation of payment of interest hereunder. As
used herein, "Business Day" means a day (i) other than Saturday or Sunday, and
(ii) on which commercial banks are open for business in Orange County,
California.

               Anything herein to the contrary notwithstanding, if during any
period for which interest is computed hereunder, the amount of interest computed
on the basis provided for in this Promissory Note, together with all fees,
charges and other payments which are treated as interest under applicable law,
as provided for herein or in any other document executed in connection herewith,
would exceed the amount of such interest computed on the basis of the Highest
Lawful Rate, the Borrower shall not be obligated to pay, and the Lender shall
not be entitled to charge, collect, receive, reserve or take, interest in excess
of the Highest Lawful Rate, and during any such period the interest payable
hereunder shall be computed on the basis of the Highest Lawful Rate. As used
herein, "Highest Lawful Rate" means the maximum non-usurious rate of interest,
as in effect from time to time, which may be charged, contracted for, reserved,
received or collected by the Lender in connection with this Promissory Note
under applicable law.

               The Borrower may prepay the outstanding amount hereof in whole or
in part at any time, without premium or penalty. Together with any such
prepayment, the Borrower shall pay accrued interest on the amount prepaid. Any
partial prepayment shall be applied to the installments of principal hereof in
reverse order of maturity.

               So long as any amount payable by the Borrower hereunder shall
remain unpaid, the Borrower will furnish to the Lender from time to time such
information respecting the Borrower's financial condition and the Collateral (as
defined below) as the Lender may from time to time reasonably request.

               The Borrower represents and warrants to the Lender that this
Promissory Note does not contravene any contractual or judicial restriction
binding on or affecting the Borrower and that this Promissory Note is the legal,
valid and binding obligation of the Borrower enforceable against him in
accordance with its terms.

               The occurrence of any of the following shall constitute an "Event
of Default" under this Promissory Note:

               (1) the failure to make any payment of principal, interest or any
other amount payable hereunder when due under this Promissory Note or the breach
of any other condition or obligation under this Promissory Note, and the
continuation of such failure or breach for ten (10) days;

               (2) the breach of any covenant under the Loan and Security
Agreement of even date herewith between the Borrower and the Lender (the "Loan
and Security Agreement"), and the continuation of such breach for ten (10) days;


                                       2
<PAGE>   19

               (3) the filing of a petition by or against the Borrower under any
provision of the Bankruptcy Reform Act, Title 11 of the United States Code, as
amended or recodified from time to time, or under any similar law relating to
bankruptcy, insolvency or other relief for debtors; or appointment of a
receiver, trustee, custodian or liquidator of or for all or any part of the
assets or property of the Borrower; or the insolvency of the Borrower; or the
making of a general assignment for the benefit of creditors by the Borrower;

               (4) any of the documents relating to the Collateral after
delivery thereof shall for any reason be revoked or invalidated, or otherwise
cease to be in full force and effect, or the Borrower or any other person shall
contest in any manner the validity or enforceability thereof, or the Borrower or
any other person shall deny that it has any further liability or obligation
thereunder; or any of the documents relating to the Collateral for any reason,
except to the extent permitted by the terms thereof, shall cease to create a
valid and perfected first priority lien in any of the Collateral purported to be
covered thereby; or

               (5) the Domestic Distributor Agreement, by and between Borrower
and Lender dated October 1, 1998, as amended, shall for any reason prior to the
expiration of its term be terminated, revoked or invalidated, or otherwise cease
to be in full force and effect, or any Person shall contest in any manner the
validity or enforceability thereof or deny that it has any further liability or
obligation thereunder.

               Upon the occurrence of any Event of Default, the Lender, at its
option, may by notice to the Borrower, declare the unpaid principal amount of
this Promissory Note, all interest accrued and unpaid hereon and all other
amounts payable hereunder to be immediately due and payable, whereupon the
unpaid principal amount of this Promissory Note, all such interest and all such
other amounts shall become immediately due and payable, without presentment,
demand, protest or further notice of any kind, provided that if an event
described in paragraph (3) above shall occur, the result which would otherwise
occur only upon giving of notice by the Lender to the Borrower as specified
above shall occur automatically, without the giving of any such notice.

               The Borrower agrees to pay on demand all the losses, costs, and
expenses (including, without limitation, attorneys' fees and disbursements)
which the Lender incurs in connection with enforcement or attempted enforcement
of this Promissory Note, or the protection or preservation of the Lender's
rights under this Promissory Note, whether by judicial proceedings or otherwise.
Such costs and expenses include, without limitation, those incurred in
connection with any workout or refinancing, or any bankruptcy, insolvency,
liquidation or similar proceedings.

               The Borrower hereby waives diligence, demand, presentment,
protest or further notice of any kind. The Borrower agrees to make all payments
under this Promissory Note without setoff or deduction and regardless of any
counterclaim or defense.

               No single or partial exercise of any power under this Promissory
Note shall preclude any other or further exercise of such power or exercise of
any other power. No delay or omission on the part of the Lender in exercising
any right under this Promissory Note shall operate as a waiver of such right or
any other right hereunder.


                                       3
<PAGE>   20

               Capitalized terms used herein but not otherwise defined herein
shall have the respective meanings given such terms in the Loan and Security
Agreement.

               This Promissory Note shall be binding on the Borrower and its
successors and assigns, and shall be binding upon and inure to the benefit of
the Lender, any future holder of this Promissory Note and their respective
successors and assigns. The Borrower may not assign or transfer this Promissory
Note or any of its obligations hereunder without the Lender's prior written
consent.

               This Promissory Note is secured by the collateral (the
"Collateral") more specifically described in the Loan and Security Agreement and
the Guarantor Security Agreement of even date herewith made by Robert F. Byrnes
in favor of the Lender (the "Guarantor Security Agreement").

               THIS PROMISSORY NOTE SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH CALIFORNIA LAW.

                                        ADVANCED MEDICAL PROCEDURES

                                        By  /s/ [Illegible]
                                            ------------------------------------
                                            Name:
                                                  ------------------------------
                                            Title:

                                                  ------------------------------
                                        Address:

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



                                       4
<PAGE>   21

                                     ANNEX 1

                                                                 Outstanding
Date of Advance               Amount Advanced                  Principal Amount
---------------               ---------------                  ----------------





                                       5