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                                                                    Exhibit 10.4

                      MARKETING AND DISTRIBUTION AGREEMENT

     This Marketing and Distribution Agreement (the "Agreement") is entered into
as of the 18th day of May, 2006, by and between MedTrak Technologies, Inc., an
Arizona corporation ("MedTrak"), and AcuNetx, Inc., a Nevada corporation
("AcuNetx").

                                    RECITALS:
                                    ---------

     A. MedTrak markets and sells video electronystagmography ("VNG") products
listed on the attached Exhibit A (the "MedTrak VNG Products").

     B. AcuNetx manufactures various medical devices, including the MedTrak VNG
Products.

     C. AcuNetx intends to create and manufacture an alternate line of VNG
products that will be marketed and branded by AcuNetx (the "AcuNetx VNG
Products"). MedTrak VNG Products and AcuNetx VNG Products will collectively be
referred to as the "Products."

     D. AcuNetx desires that MedTrak be the exclusive company to market and sell
the MedTrak VNG Products, and MedTrak desires that AcuNetx be the sole and
exclusive manufacturer of the MedTrak VNG Products.

                                   AGREEMENT:
                                   ----------

     1. Exclusive Dealings for MedTrak VNG Products.

          1.1 AcuNetx grants to MedTrak the exclusive right to market and sell
the MedTrak VNG Products. MedTrak grants to AcuNetx the exclusive right to
manufacture the MedTrak VNG Products.

          1.2 MedTrak may market and distribute the MedTrak VNG Products itself
or through distributors or sub-distributors (collectively referred to as
"Distributors"), provided that AcuNetx approves the Distributor's contract(s)
with MedTrak, such approval(s) not to be unreasonably withheld. AcuNetx hereby
consents to the current Distributor contracts listed on Exhibit B.

          1.3 MedTrak and its Distributors may market and sell the MedTrak VNG
Products under a "private label" as they are currently labeled in Exhibit A,
including the MedTrak brand and sub-brands MobiTrak, ScottTrak and OtoTrak. No
additional or new naming or branding of MedTrak VNG products manufactured by
AcuNetx may occur.

     2. MedTrak VNG Product Improvements.

          2.1 As AcuNetx creates and develops the AcuNetx VNG Products, it will
make any improvements that are part of the AcuNetx VNG Products available to
MedTrak and its Distributors to be incorporated in the MedTrak VNG Products
under the MedTrak "private label" provisions of Section 1.3. The price and
commission structure for the improved MedTrak VNG Products will be separately
negotiated as these product improvements become available. The parties agree
that the price and commission structure will be comparable with AcuNetx products
distributed by other AcuNetx distributors.

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          2.2 MedTrak agrees to adhere to the AcuNetx marketing and branding
standards in compliance with applicable FDA labeling regulation and
requirements.

     3. Exclusive Manufacturer. During the term of this Agreement, MedTrak
agrees not to distribute or sell any VNG products other than those manufactured
by AcuNetx.

     4. Purchase Orders. Each sale of any MedTrak VNG Product will be initiated
by MedTrak's delivery to AcuNetx of a written purchase order specifying in
reasonable detail the type, quantity, delivery date, and shipping destination
information for the MedTrak VNG Product ordered (the "Purchase Order"). No
Purchase Order will be binding on AcuNetx until accepted in writing by AcuNetx.
If any Purchase Order is not rejected in writing and delivered to MedTrak by
AcuNetx within three business days of AcuNetx's receipt of the Purchase Order,
then Purchase Order will be deemed accepted as submitted.

     5. Delivery.

          5.1 Type of Delivery. All Products delivered will be FOB AcuNetx's
plant or other place of shipment. AcuNetx will use its best efforts to deliver
Products by the applicable delivery date to the destination specified in each
Purchase Order. All customs duties, costs, taxes, insurance premiums, and other
expensive expenses relating to such transportation and delivery will be at the
recipient's expense.

          5.2 Packaging. AcuNetx will package the product in its standard
shipping packages.

          5.3 Set Up and Compliance. MedTrak will be responsible for assisting
end- users with setting out and ensuring Product compliance with Product
specifications at the time of setup.

     6. Price, Commission. and Payment.

          6.1 Commission-based Payment to MedTrak. If AcuNetx ships MedTrak VNG
Products directly to the end user, AcuNetx will book and collect the end-user
sales price. AcuNetx will then pay MedTrak a commission (the "Commission"),
which shall be the difference between the wholesale price to MedTrak for the
MedTrak VNG Products, as provided in writing to MedTrak (the "MedTrak Wholesale
Price"), and the end-user sales price. AcuNetx shall pay the Commission to
MedTrak within three business days after AcuNetx's has been paid for the Product
from the end-user.

          6.2 Wholesale Price Payment to AcuNetx. If for any reason AcuNetx
transfers title of the MedTrak VNG Products to MedTrak, together with the
responsibilities and liabilities of such title transfer, AcuNetx will ship
Product directly to MedTrak, and MedTrak shall pay AcuNetx the wholesale price
for the Product within 15 calendar days of invoice.


                                       2
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          6.3 Payment to MedTrak Distributors. MedTrak will be responsible for
payment of commissions to all of its Distributors and will indemnify AcuNetx
from any MedTrak Distributor claims of non-payment.

     7. Term and Termination.

          7.1 The Term of this Agreement will be for eight years and will
automatically be renewed for an additional three year term thereafter
(Additional Terms) unless notice of termination is given in writing by either
party at least 90 days prior to the end of the Initial Term or any Additional
Term.

          7.2 If either party materially breaches in provision of this Agreement
and the breach is not cured or steps initiated to remedy the breach to the other
parties reasonable satisfaction within 30 days after receipt of notice
specifying the breach, the party not in breach may terminate this Agreement.

     8. Prior Agreement. The parties had previously signed an Exclusive
Manufacturing, Sales, Licensing and Software Ownership Agreement dated March 22,
2004, as well as an Addendum signed on October 27, 2004 (collectively referred
to as the "Prior Agreement"). The parties hereby agree to cancel and terminate
the Prior Agreement, effective as of the date of this Agreement, except for any
amounts that are owed between the parties for transactions entered into prior to
the effective date of this Agreement. This Agreement supersedes and replaces the
Prior Agreement.

     9. Confidential Information.

          9.1 AcuNetx Confidential Information. AcuNetx has developed, on its
own accord and is in possession of certain proprietary and confidential source
codes, schematics, lists of contractors, proprietary information and trade
secrets (collectively referred to as "AcuNetx Confidential Information) related
to the Products that are utilized in the manufacture of the Products. AcuNetx
has previously delivered the Confidential Information to Anker, Reed, Hymes &
Schreiber, a Law Corporation (hereafter Anker, Reed) for storage and
safekeeping.

               9.1.1 Access to AcuNetx's Confidential Information. MedTrak
          acknowledges that it and its employees will be exposed to and have
          access to the AcuNetx Confidential information during the term of this
          Agreement.

               9.1.2 MedTrak agrees to use the AcuNetx Confidential Information
          only to the extent necessary to perform its marketing and sales
          obligations under this Agreement and will not disclose, during the
          term of this Agreement, and at all times thereafter, any of the
          AcuNetx Confidential Information to any third party without the prior
          written consent of AcuNetx.

               9.1.3 MedTrak acknowledges that irreparable injury will result to
          AcuNetx in the event of a breach of this section, and in the event of
          such breach, AcuNetx will be entitled to an injunction to restrain the
          violation by MedTrak, its employees, and all persons acting for or
          with it. Injunctive relief will be in addition to any other remedies
          and damages available.


                                       3
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          9.2 MedTrak Confidential Information. MedTrak has developed, on its
own accord and is in possession of certain proprietary and confidential source
codes, schematics, lists of contractors, proprietary information and trade
secrets (collectively referred to as "MedTrak Confidential Information") related
to the Products that are utilized in the manufacture of the Products.

               9.2.1 Access to MedTrak's Confidential Information. AcuNetx
          acknowledges that it and its employees will be exposed to and have
          access to the MedTrak Confidential Information during the term of this
          Agreement.

               9.2.2 AcuNetx agrees to use the MedTrak Confidential Information
          only to the extent necessary to perform its development and
          manufacturing obligations under this Agreement and will not disclose
          during the term of this agreement and at all times thereafter, any of
          the MedTrak Confidential Information to any third party without the
          prior written consent of MedTrak.

               9.2.3 AcuNetx acknowledges that irreparable injury will result to
          MedTrak in the event of a breach of this section, and in the event of
          such breach MedTrak will be entitled to an injunction to restrain the
          violation by AcuNetx, its employees and all persons acting for or with
          it. Injunctive relief will be in addition to any other remedies in
          damages available.

     10. Ownership and Licenses of Software. MedTrak will be the exclusive owner
of the software, including upgrades, used in the MedTrak VNG Products (the
"Software"). All right, title, and interest, including copyright rights, of the
Software is hereby vested, and future upgrades will be vested, in MedTrak.
MedTrak hereby grants AcuNetx an exclusive license to use the Software during
the term of this Agreement.

     11. Inability of AcuNetx to Provide Products. If AcuNetx is not capable of
meeting MedTrak's sales requirements for the MedTrak VNG Products, AcuNetx will,
within 10 days, inform MedTrak of such inability to perform. Within 10 days
after so informing MedTrak, AcuNetx will direct Anker, Reed to make the AcuNetx
Confidential Information available to MedTrak so as to ensure MedTrak's ability
to continue to manufacture the MedTrak VNG Products. If the inability to provide
MedTrak VNG Products is temporary, AcuNetx may grant permission to. MedTrak to
have the Products manufactured by an alternative supplier, which supplier must
first be approved by AcuNetx. If MedTrak utilizes the AcuNetx Confidential
Information, MedTrak will compensate AcuNetx for each MedTrak VNG Product not
manufactured by AcuNetx in an amount equal to 10% of MedTrak's then current cost
to purchase the Product from AcuNetx

     12. Warranties, Support and Repairs. AcuNetx will provide each end-user of
the Products with AcuNetx's standard warranty coverage and also provide
technical support and repairs consistent with its warranty obligations. MedTrak
will not make any representation or give any warranties or guarantees to any
person with respect to any of the Products or related services, other than those
representations, warranties, or guarantees that AcuNetx has specifically
authorized.


                                       4
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     13. Indemnification. The parties agree that each party is solely
responsible for the performance of its duties, and each agrees to indemnify and
hold the other harmless from and against any and all claims asserted against the
other for loss or damage to property including claims for economic and business
injury, to persons or firms and all injury or death to third persons, including
all expenses incident to any of the foregoing claims, in any way arising out of
or relating to the conduct of such party's business and performance under this
Agreement. Each party further agrees to defend the other and the other's agents
and employees from and against any claim, demand, cause of action, damage, loss,
cost or expense arising from or in connection with its actions or failures to
act. Neither party may take any action that would have the effect of causing the
other to be in violation of any rules, decrees, laws or regulations.

     14. Expenses. Each party agrees to bear their own expenses in connection
with the negotiation of this Agreement, including but not limited to, attorneys'
fees, accounting fees, and other out-of-pocket expenses

     15. Press Release. Both parties agree to cooperate in preparing a press
release describing this Agreement. The press release will be submitted for
release unless legal counsel advises that for compliance purposes it must be
released sooner or later. Except as provided in this Section, neither party may
release any information to the public or the media without the consent of the
other party.

     16. Miscellaneous.

          16.1 Entire Agreement. This Agreement contains the entire agreement of
the parties regarding the subject matter and supersedes all prior agreements,
understandings and negotiations regarding the same, including the Prior
Agreement and that certain Letter of Intent dated April 20, 2006.

          16.2 Assignment. This Agreement may not be assigned by either party
without the prior written consent of the other party.

          16.3 Severability. If any provision of this Agreement is held to be
illegal or unenforceable, that provision will be limited or eliminated to the
minimum extent necessary so this Agreement will otherwise remain in full force
and effect.

          16.4 Further Assurances. Each party agrees to execute, acknowledge and
deliver such further instruments, and to do all such other acts as may be
necessary or appropriate in order to carry out the purposes and intent of this
Agreement.

          16.5 Use of Party's Name. No right, express or implied, is granted by
this agreement to either party to use in any manner not expressly provided for
in this Agreement the name of the other party or any other trademark or trade
name of the other in connection with the performance of this agreement.


                                       5
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          16.6 Notices. All notices, demands, requests, elections or other
communications required or permitted to be given by any party to the other will
be in writing and will be (a) personally delivered; (b) sent via facsimile
transmission; or (c) deposited in the United States mail, first-class certified
postage prepaid, return receipt requested, and addressed to the parties as
follows:

                                   To AcuNetx:
                                   -----------

                      1000 S. McCaslin Boulevard, Suite 300
                            Superior, Colorado 80027
                         Attention: Terry R. Knapp, M.D.
                               (F) (303) 494-1714

                                 With a Copy to:

                             Michael J. Tauger, Esq.
                                5445 DTC Parkway
                                    Suite 520
                           Greenwood Village, CO 80111
                               (F) (303) 770-7257

                                   To MedTrak:
                                   -----------

                              10182 E. Cactus Road
                              Scottsdale, AZ 85260
                               (F) (413) 826-7905
                            Attention: Mel Shadowens

                                 With a Copy to:

                            Gallagher & Kennedy, P.A.
                            2575 East Camelback Road
                             Phoenix, Arizona 85016
                               (F) (602) 530-8500
                          Attention: Michael W. Murphy

Notices, demands, requests, elections, or other communications will, if
personally delivered, be effective upon receipt; if mailed, will be effective
upon the earlier of (a) actual receipt, (b) four days after first being
deposited in the United States mail as indicated by the postmark thereon; or (c)
if sent via facsimile, be effective upon delivery so long as the sender's
facsimile machine provides written proof of successful transmission. Notice of a
change of address must be in the manner provided for the giving of other
notices.

          16.7 Relationships of the Parties. Nothing contained in this agreement
is intended to be construed so as to constitute AcuNetx and MedTrak as partners
or joint venturers with each other. Neither party will have any express or
implied right or authority to assume or create any obligations on behalf of or
in the name of the other party or to bind the other party to any contract,
agreement or undertaking with any third party.


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<PAGE>

          16.8 Waiver and Modifications. The waiver by either party of a breach
of any provision will in no way be construed as a waiver of any subsequent
breach of such provision or the waiver of the provision itself. This Agreement
may not be changed, modified, amended or supplemented except by written
instrument signed by both parties.

          16.9 Applicable Law. This agreement will be governed by and construed
in accordance with the laws of the State of Colorado, without regard to conflict
of laws provisions. The proper venue for any proceeding at law or in equity will
be (i) Maricopa County, Arizona, if AcuNetx commences any proceeding against
MedTrak; and (ii) Boulder County, Colorado if MedTrak commensec any proceeding
against AcuNetx. The parties waive any right to object to the venue. The
prevailing party in any legal action to enforce or interpret this Agreement will
be entitled to reasonable costs and attorney's fees.

          16.10 Captions. Section captions are for convenience only and are not
to be construed to define, limit or affect the construction or interpretation of
this Agreement.

          16.11 Force Majeure. A party will not be liable for nonperformance or
delay in performance (other than of obligations regarding payment of money or
confidentiality) caused by any event reasonably beyond the control of such party
including, but not limited to wars, hostilities, revolutions, riots, civil
commotion, national emergency, strikes, lockouts, unavailability of supplies,
epidemics, fire, flood, earthquake, force of nature, explosion, embargo, or any
other act of God, or any law, proclamation, regulation, ordinance, or other act
or order of any court, government or governmental agency.

          16.12 Counterparts. This Agreement may be executed in any number of
counterparts, each of which will be deemed to be an original as against any
party whose signature appears here on, and all of which will together constitute
one and the same instrument. This Agreement will become binding in one or more
counterparts hereof, individually or taken together, they are the signatures of
all the parties reflected here on as the signatories.

          16.13 No Presumption. This Agreement has been negotiated among the
parties and if there is any ambiguity, no presumption construing the Agreement
against a party may be imposed because this Agreement was prepared by counsel
for one party or the other.

     IN WITNESS WHEREOF, the parties have signed this agreement to be effective
as of the date first written above.


MEDTRAK TECHNOLOGIES, INC.,                      ACUNETX, INC.,
an Arizona corporation,                          a Nevada corporation


/s/ Mel Shadowens                                /s/ Terry R. Knapp 5/24/06
-----------------                                --------------------------
Mel Shadowens, Ph.D., Member                     Terry R. Knapp, M.D.
                                                 Chief Executive Officer


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                                    EXHIBIT A

                              MEDTRAK VNG PRODUCTS


1.   MedTrak single camera 2 channel VNG system. This system includes the
     following:

Goggle Assembly single camera
9" video monitor
Inferface Cpntroller 2003 AHR
Active Head Rotation Infrared transmitter
Active Head Rotation Receiver
DC Power Supply
Computer (Tower or Laptop)
Keyboard
Mouse
Footswitch
17" Flat Screen CRT Monitor
Printer HP
Printer Cable
IF/Computer Cable
One each 48" video cable
ten each goggle pads
MedTrak VNG Operating Manual
MedTrak Software Disk
Windows XP
AC Power Center
One Atmos Air Caloric Irrigator (Bithermal)
One year warranty

2.   Mobi-Trak single camera 2 channel VNG system. This system includes the
     following:

Goggle Assembly single camera
Inferface Cpntroller 2003 AHR
Active Head Rotation Infrared transmitter
Active Head Rotation Receiver
DC Power Supply
Compute Laptop
One MobiTrak Carrying Case
Footswitch
Printer HP
Printer Cable
IF/Computer Cable
One each 48" video cable
ten each goggle pads
MobiTrak VNG Operating Manual
MobiTrak Software Disk

<PAGE>

Windows XP
AC Power Center
One Atmos Air Caloric Irrigator (Bithermal)
One year warranty

3.   ScottTrak VNG single camera 2 channel system. This system includes the
     following:

Goggle Assembly single camera
9" video monitor
Inferface Cpntroller 2003 AHR
Active Head Rotation Infrared transmitter
Active Head Rotation Receiver
DC Power Supply
Computer (Tower or Laptop)
Keyboard
Mouse
Footswitch
17" Flat Screen CRT Monitor
Printer HP
Printer Cable
IF/Computer Cable
One each 48" video cable
ten each goggle pads
ScottTrak VNG Operating Manual
ScottTrak Software Disk
Windows XP
AC Power Center
One Atmos Air Caloric Irrigator (Bithermal)
One year warranty

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                                    EXHIBIT B

                              DISTRIBUTOR CONTRACTS

Balance & Vestibular Systems, LLC aka InBalance, LLC
11315 Business Park Blvd
Jacksonville, Fl 32256

ScottPT
35 Dora Lane
Holmdel, NJ 07733

AmeriBalance
355 Brainards Rd
Harmony Township
Philipsburg, NJ 08865