In the normal course of business, we have been and will likely continue to be subject to litigation or administrative proceedings incidental to our business, such as claims related to customer disputes, employment practices, wage and hour disputes, product liability, professional liability, commercial disputes, licensure restrictions or denials, and warranty or patent infringement. Responding to litigation or administrative proceedings, regardless of whether they have merit, can be expensive and disruptive to normal business operations. As litigation and the administrative proceedings are inherently uncertain, we cannot predict the outcome of such matters. We can provide no assurance that the ultimate outcome, either individually or in the aggregate, will not have a material adverse effect on our business or financial results.

Risks Related to Our Business and Industry

Our industry is highly competitive.

The nuclear imaging industry is highly competitive, subject to rapid change and significantly affected by new product introductions and market activities of other industry participants. Our primary competitors with respect to nuclear imaging systems include Philips Medical Systems, General Electric Healthcare and Siemens Medical Systems. All of these competitors offer

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a full line of imaging cameras for each diagnostic imaging technology, including x-ray, magnetic resonance imaging, computerized tomography, ultrasound and nuclear medicine, as well as hybrid modalities that combine, for example, the technologies of positron emission tomography, or PET, with computed tomography, or CT. Many of our competitors and potential competitors enjoy significant advantages over us, including significantly greater name recognition and financial, technical, service and marketing resources; established relationships with healthcare professionals, customers and third-party payors; established distribution networks; technical features our current products do not possess; multiple product lines and the ability to offer rebates or bundle products to offer discounts or incentives; and greater resources for product development, sales and marketing.

Certain medical device companies are developing solid-state cameras that may compete with our product offerings. A privately-held company, Gamma Medica, is marketing a solid-state gamma camera for breast imaging. A second company, Spectrum Dynamics, is marketing a solid-state gamma camera that we believe may be marketed in the cardiac segment. A third company, Mid-Atlantic Imaging, is marketing a mobile cardiac camera based on vacuum tube technology. We anticipate that additional companies will dedicate resources to developing competing products and services that may demonstrate better image quality, ease of use or mobility than our imaging systems. If we are unable to compete effectively against our existing and future competitors, our sales will decline and our business will be harmed.

In providing DIS lease services, we compete against small businesses employing traditional vacuum tube cameras that cannot be moved in and out of physician offices. We also compete against physicians and companies that use Digirad and other cameras in local and regional mobile imaging businesses, some of which have the advantage of a lower cost structure, and competition from these mobile operations may increase. In addition, we compete against imaging centers that install nuclear gamma cameras and make them available to referring physicians in their geographic vicinity. If these competitors are able to win significant portions of our business, our sales will decline and our business will be harmed.

The competitive nature of the nuclear imaging industry has affected the volume of both our camera sales and our leasing services, and the pricing of our gamma cameras. We anticipate that these pressures will continue.

In providing ultrasound imaging lease services, we compete against many small businesses, many of which have lower operating costs. If we cannot win business from these competitors, our plans of increasing our ultrasound leasing business may fail and our overall business may be harmed.

If the market for nuclear imaging cameras continues to decrease, or if we are not successful in expanding our market share or product and service offerings, our revenues will decline and our business will be harmed.

Data from the National Electrical Manufacturers Association, or NEMA, indicates that sales of nuclear imaging equipment, excluding maintenance revenue, declined approximately 10% in 2006, and NEMA forecasts the rate of descent to slow in 2007 to approximately 5%; data from NEMA further indicates that sales of general nuclear imaging equipment increased approximately 1% in the first quarter of 2007 when compared to the first quarter of 2006, and the market for cardiac-specific nuclear cameras increased 7% in the first quarter of 2007 when compared to the first quarter of 2006. We believe this decline may be attributable to concerns about reimbursement changes and the increasing adoption of alternative imaging modalities, such as magnetic resonance imaging, computerized tomography, positron emission tomography, and hybrids among these modalities. We believe our market has been negatively affected by declining and more restricted reimbursement, significant pricing pressures in the product business and increased competition in the mobile imaging business. We expect each of these trends to continue.

If these trends continue and we are unable to offset their effects on our business by expanding our market share or successfully introducing alternative products and services, our business will be significantly harmed.

Changes in coverage and reimbursement policies of third-party payors may adversely affect our ability to market and sell our products and services.

Private third-party payors continue to act to contain or reduce healthcare costs through various means, including the movement to managed care systems where healthcare providers contract to provide comprehensive healthcare for a fixed fee per patient. Some third party payors in geographic locations currently served by us issued guidelines preventing our physician customers from obtaining reimbursement for procedures they perform unless they own or lease our cameras on a full time basis. These and other payors are also requiring physicians to be accredited by either the Intersocietal Commission for the Accreditation of Nuclear Medicine Laboratories (ICANL) or by the American College of Radiology, and to meet certain other privileging standards. Some of these privileging standards also exclude physicians who are not radiologists or cardiologists from obtaining reimbursements for the professional component of nuclear imaging procedures. An increasing number of our DIS customers are non-cardiologists who would not currently meet the certifications required by payors in certain geographic areas. We have obtained accreditation from the Intersocietal Commission for the Accreditation of Nuclear Medicine Laboratories for 27 of our hub locations to address certification requirements.

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Third party payors have also begun to require accreditation for certain ultrasound imaging procedures, and we are in the process of submitting an application to obtain ultrasound imaging accreditation through the Intersocietal Commission for the Accreditation of Echocardiography Laboratories. We cannot assure you that we will be successful in obtaining additional certifications, or that obtaining them will satisfy the requirements of these payors. We also cannot assure you that these third party payor guidelines will be changed, or that they will not be adopted by other third party payors, including Medicaid and Medicare. These continued efforts to restrict reimbursement have resulted in the denial of reimbursement in some instances. An increase in such denials will negatively affect our DIS business and product sales.

Acquisitions could adversely affect our operations and create unanticipated liabilities and other harmful consequences.

We have acquired substantially all of the assets of Ultrascan and may make additional acquisitions and strategic investments in the future. We cannot assure you that we would be able to successfully complete any acquisition or that we will be able to successfully integrate any acquired business, product or technology into our company in a cost-effective and non-disruptive manner. The Ultrascan acquisition, as well as any future transactions, may also result in dilutive issuances of equity securities, use of our cash resources, incurrence of debt and amortization of expenses related to intangible assets. Such transactions could be material to our financial condition and results of operations. In addition, the process of integrating an acquired company, business or technology may create unforeseen operating difficulties and expenditures and is risky. Acquisitions involve risks, including:

Our failure to be successful in addressing these risks or other problems encountered in connection with our past or future acquisitions and strategic investments could cause us to fail to realize the anticipated benefits of such acquisitions or investments, incur unanticipated liabilities and harm our business generally.

In addition, Ultrascan has not been required to prepare a report on the effectiveness of its internal controls over financial reporting because it was not subject to the informational requirements of the Securities Exchange Act of 1934, as amended. We have implemented process and controls over revenue and operating expenses since we acquired Ultrascan in May 2007, but, as of June 30, 2007, we have not tested the operating effectiveness of the new internal controls related to the integration of Ultrascan. While we expect to complete this process by the end of the second quarter of 2008, we cannot assure you that the measures we have taken to date or any future measures will be sufficient. Any failure to develop or maintain effective controls, or any difficulties encountered n their implementation or improvement, could harm our operating results or cause us to fail to meet our reporting obligations and may result in a restatement of our prior period financial statements. Ineffective internal controls could also cause investors to lose confidence in our reported financial reporting.

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Failure to attract qualified managers, engineers and imaging technologists, or high employee attrition rates, could limit our growth and adversely affect our business.

Our success is dependent on the efforts of our key executives and technical, sales and managerial personnel and our ability to retain them. Losing one or more of these individuals could place a significant strain on our remaining management team and we may have difficulty replacing any of these individuals. Our future growth and ability to generate profits will depend in part upon our ability to identify, hire and retain nuclear imaging technologists, certified cardiographic technicians, trained and registered sonographers, nurses, radiation safety officers, engineers, management, sales personnel and other highly skilled personnel.

Hiring qualified management and technical personnel will be difficult due to the limited number of qualified candidates. Competition for these types of employees, particularly nuclear imaging technologists and engineers, is intense in the medical imaging field. Failure to attract, hire and retain key personnel could have an adverse effect on our business, financial condition and results of operations. For the six months ended June 30, 2007, we experienced a 22% rate of employee turnover for the combined service and product segments. If we are unable to improve upon this metric, our business and financial condition may continue to be adversely affected.

Our imaging systems and DIS services may become obsolete, and we may not be able to timely develop new products, product enhancements or services that will be accepted by the market.

Our nuclear and ultrasound imaging systems and DIS services may become obsolete or unmarketable as other products or services utilizing new technologies or the development of hybrid imaging modalities are introduced by our competitors or new industry standards emerge. We cannot assure you that any future products and enhancements will be accepted by the market. To be successful, we will need to enhance our products or services and to design, develop and market new products that successfully respond to competitive developments, all of which may be expensive and time consuming.

The success of any new product offering or enhancement to an existing product will depend on several factors, including our ability to properly identify and anticipate physician and patient needs; develop or acquire new products or enhancements in a timely manner; obtain the necessary regulatory approvals or clearances for new products or product enhancements in a timely manner; provide adequate training to users of our products; price our products competitively; obtain required licensure; continue to offer cost-competitive products and services despite increasing reimbursement restrictions and pricing pressures; comply with changing or new regulatory requirements; and develop an effective marketing, sales and distribution network.

If we are unable to meet these requirements, our business, financial condition and results of operations will suffer. In addition, even if our customers acquire new products, services or product enhancements, the revenues from such sales may not be sufficient to offset the significant costs associated with developing and offering such products, services or enhancements to customers. In addition, any announcements of new products, services or enhancements may cause customers to decline or cancel their purchasing decisions in anticipation of replacements.

If we are unable to expand our DIS business, our growth rates could be significantly diminished and our business could be materially harmed.

We plan to grow our DIS business by expanding into new states, adding new hub locations in states in which we currently operate and increasing existing hub and asset utilization by adding physician customers and routes. Our progress in expanding into new geographies has been slower than anticipated, we have closed unprofitable hubs, our hub utilization and customer density in some geographies have decreased, and we cannot assure you that we will be able to sell our leasing services at the rates we anticipate, or that physicians or hospitals in these new markets will accept our imaging products or services, or that we can retain our current customers. Our expansion into additional markets is subject to inherent risks, including those associated with compliance with applicable state laws and regulations. We may find the laws of states in which we do not currently operate preclude us from operating our DIS business, or require us to change the structure in which we operate our DIS business in such states. In addition, our inability to build awareness of our DIS business through alliances with centers of influence, such as academic institutions and medical centers, could also limit our ability to succeed in these potential markets. Our inability to expand into new markets for any of these reasons could diminish our prospects for growth and profitability.

Because our imaging systems and DIS services are not widely diversified, a decrease in sales of our products and leasing services could seriously harm our business.

Our current product and service offerings consist primarily of our line of gamma cameras, including our Cardius-1, Cardius-2, and Cardius-3 XPO Series, 2020 tc Imager and SPECTpak PLUS camera systems, all designed for use in the nuclear imaging market segment. We deliver ultrasound imaging services using equipment developed and sold by third parties. In addition, our DIS nuclear

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imaging leasing service utilizes our own line of cameras and at present is focused nearly exclusively on nuclear cardiology. As such, our line of products and services is not as diversified as those of some of our competitors. If the sales of our products or leasing services decline, our business would be seriously harmed, and it would likely be difficult for us to sustain our business while seeking to develop new types of products or services or other markets for our existing products and services. In addition, because our technical know-how and intellectual property have limited applications, we may be unable to leverage these assets to diversify our products and services or to develop other products or sources of revenue outside of the nuclear and ultrasound imaging market.

If we experience problems with the technologies used in our imaging systems or if delivery of our DIS services is delayed, public perception of our products and service offerings could be harmed and we may lose customers and revenue.

We have experienced some reliability issues with our camera detector heads and other parts of our imaging systems, and some of the cameras in our DIS fleet are more than four years old. Although we have embarked on a program to upgrade our fleet over a three year horizon, as the period of use of our cameras and ultrasound equipment increases, other defects may occur. Additionally, physicians rely on our DIS services to provide nuclear and ultrasound imaging procedures to their patients on the dates and at the times they have leased. Many factors could prevent us from delivering our DIS services on a timely basis, including equipment failures, unanticipated problems with our mobile Cardius-3XPO camera, weather and the availability of staffing, transportation and necessary supplies. If we are unable to provide physicians or hospitals with our DIS services in a timely and efficient manner, our business would be harmed.

We are subject to the financial risks associated with providing services through our DIS business.

There are numerous risks associated with any leasing arrangement, including the possibility that physicians may fail to pay us because of general economic and business conditions, the availability of reimbursement or other reasons. In addition, the number of physicians each quarter who either bought their own cameras, terminated their mobile imaging service contracts or switched to other mobile imaging service providers increased during the second half of 2006, and has remained at approximately the same number over the past three quarters. If this trend were to increase, our business and financial condition could be adversely affected.

Our manufacturing operations are highly dependent upon third-party suppliers, making us vulnerable to supply problems and price fluctuations, which could harm our business.

We rely on a limited number of third parties to manufacture and supply certain of the key components of our products and services. While many of the components used in our products are available from multiple sources, we obtain some components from single sources, and alternative sources for them may not be readily available. For example, key components of the detector heads and the processing and control software utilized in our gamma cameras are manufactured or supplied by a single source. If we were unable to obtain these components, our ability to build gamma cameras could be materially affected, and we could experience delays in the production of our gamma cameras for an extended period of time that could cause the loss of customers and revenue. Also, we rely on third parties to supply us with radionuclides for use in our nuclear imaging leasing service. If such supplies become subject to a recall or are disrupted, our leasing services could be materially disrupted.

We have limited marketing, sales and distribution capabilities.

Our future revenue growth will depend in large part on our success in maintaining and expanding our marketing, sales and distribution channels, which is an expensive and time-consuming process. We are highly dependent upon the efforts of our sales force and third-party distributors to increase our revenue. We use eight independent distributors in the United States and two independent, international sales distributors to market, sell and distribute our products and services. Seven of our domestic distributors are either prohibited from selling competitive products or must use their best efforts not to do so. One of our domestic distributors may sell imaging products that are used or refurbished, meet specified age requirements and are non-cardiac nuclear imaging systems. Our international distributors may sell competing imaging products that are used or refurbished and meet specified age requirements. We face competition for qualified sales employees and may be unable to hire, train, manage and retain such personnel, which could adversely affect our ability to maintain and expand our marketing, sales and distribution network. If we are unable to maintain and expand our direct and third-party marketing, sales and distribution networks, we may be unable to sell enough of our products and imaging services for our business to be profitable and our financial condition and results of operations will likely suffer.

We are exposed to risks relating to product liability, product recalls, property damage and personal injury and death for which insurance coverage is expensive and potentially inadequate, and our business may be negatively affected by insufficiently insured claims and increased insurance costs.

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Our operations entail risks relating to claims or litigation relating to product liability, warranty, product recalls, property damage, misdiagnosis, personal injury and death. We may incur significant liability in the event of any such litigation, regardless of the merit of the action. We currently maintain insurance that we believe is adequate with respect to the nature of the risks insured against, including product liability insurance, professional liability insurance, automobile insurance, property insurance, workers compensation insurance and general liability insurance. In many cases such insurance is expensive, and no assurance can be given that we will be able to maintain our current insurance or that we will be able to obtain or maintain comparable or additional insurance in the future on reasonable terms. If we are unable to obtain insurance, or if our insurance is inadequate to cover claims, our cash reserves and other assets could be jeopardized. Additionally, costs associated with maintaining our insurance could become prohibitively expensive, and our ability to become profitable could be diminished.

Our manufacturing operations and executive offices are located at a single facility that may be at risk from fire, earthquakes or other natural or man-made disasters or crises.

Our manufacturing operations and executive offices are located at a single facility in Poway, California, near known fire areas and earthquake fault zones. We have taken precautions to safeguard our facilities, including insurance and health and safety protocols. However, any future natural disaster, such as a fire or an earthquake, could cause substantial delays in our operations, damage to or destroy our manufacturing equipment or inventory, and cause us to incur additional expenses. The insurance we maintain against fires and other natural disasters may not be adequate to cover our losses in any particular case.

The substitution of generic radiopharmaceuticals for one of the patent-protected radiopharmaceutical commonly used by our physician clients could affect our financial results.

We generate revenue by providing radiopharmaceuticals used in nuclear imaging to our physician customers under our radioactive materials licenses. If the loss of patent protection by one or more such radiopharmaceuticals results in the use of generic versions at significantly lower prices, our revenue and earnings could decline.

Risks Related to Government Regulation

We must be licensed to handle and use hazardous materials and may be liable for contamination or other harm caused by hazardous materials that we use.

We use hazardous and radioactive materials in our research and development and manufacturing processes, as well as in the provision of our nuclear imaging services. We are subject to federal, state and local laws and regulations governing use, storage, handling and disposal of hazardous and radioactive materials and waste products, or hazardous materials. We are currently licensed to handle such hazardous materials in all states in which we operate, but there can be no assurances that we will be able to maintain those licenses in the future. In addition, we must become licensed to handle hazardous materials in all states into which we plan to expand. Obtaining and maintaining those additional hazardous materials licenses is an expensive and time consuming process. If we are unable to obtain and maintain the requisite licenses, we will not be able to expand into a state and our ability to grow and become profitable will be reduced. Additionally, we cannot completely eliminate the risk of contamination or injury resulting from hazardous materials and we may incur liability as a result of any such contamination or injury. In the event of an accident, we could be held liable for damages or penalized with fines and the liability and associated legal costs could exceed our resources.

We have also incurred and may continue to incur expenses related to compliance with environmental laws. Such future expenses or liability could have a significant negative impact on our business, financial condition and results of operations. Further, we cannot assure you that the cost of complying with these laws and regulations will not materially increase in the future.

We spend considerable time and money complying with federal and state laws, regulations, and other rules, and, if we are unable to comply with such laws, regulations and other rules, we could face substantial penalties.

We are directly, or indirectly through our clients, subject to extensive regulation by both the federal government and the states in which we conduct our business, including the federal Medicare and Medicaid anti-kickback laws; other Medicare laws, regulations, rules, manual provisions, and policies that prescribe the requirements for coverage and payment for services performed by us and our DIS customers; the federal False Claims statutes; the federal Health Insurance Portability and Accountability Act of 1996, or HIPAA; the Stark Law; the federal Food, Drug and Cosmetic Act; federal and state radioactive materials laws; state food and drug and pharmacy laws and regulations; state laws that prohibit the practice of medicine by non-physicians and fee-splitting arrangements between physicians and non-physicians; state scope-of-practice laws that require either specific licenses or certifications for our personnel or their direct supervision by the site physician to perform certain tasks in the absence of such licensures or certifications; federal laws, regulations, rules and policies that permit physicians to bill and receive payment for certain diagnostic tests under the

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Medicare Physician Fee Schedule only if certain conditions are satisfied, including the requirement that the physician either personally perform, or adequately supervise the performance of, the tests using equipment they own or lease, and that prohibit physicians from marking up the cost of tests they “purchase,” rather than perform or supervise, for Medicare patients; and state law equivalents to any of the foregoing federal laws.

We maintain a compliance program to help identify and correct any compliance issues and remain in compliance with all applicable laws, to train employees, to audit and monitor the Company’s operations, to provide for a compliance hotline, and to achieve other compliance goals. Like most companies with compliance programs, we occasionally discover compliance concerns. In such cases, we take responsive action, including, when necessary, corrective measures. There can be no assurance that the Company’s responsive actions will insulate us from liability associated with any detected compliance concerns.

If our past or present operations are found to be in violation of any of the laws, regulations, rules or policies described above or the other laws or regulations to which we or our customers are subject, we may be subject to civil and criminal penalties, damages, fines, exclusion from federal or state health care programs, or the curtailment or restructuring of our operations. Similarly, if our customers are found to be non-compliant with applicable laws, they may be subject to sanctions, which could have a negative impact on us. If we are excluded from federal or state health care programs, our customers who participate in those programs could not do business with us. In addition, if we are required to obtain permits or licensure that we do not possess, we may become subject to substantial additional regulation or incur significant expense. Any penalties, damages, fines, curtailment or restructuring of our operations would adversely affect our ability to operate our business and our financial results. Any action against us for violation of these laws, even if we successfully defend against it, could cause us to incur significant legal expenses, divert our management’s attention from the operation of our business and damage our reputation.

Legislative or regulatory reform of the healthcare system may affect our ability to sell our products.

Federal and state lawmakers from time to time enact new legislation establishing significant changes in the healthcare system. Downward changes to Medicare reimbursement rates for items such as the procedures our physician clients perform or the drugs used in conjunction with them may adversely affect reimbursement to customers or potential customers that use or could use our cameras and services, and may therefore affect us. Effective January 2007, the “technical component” of Medicare reimbursement for nuclear imaging services performed in physicians’ offices was capped at the lesser amount of either the Hospital Outpatient Prospective Payment System rates or the Medicare Part B Physician Fee Schedule rates. As a result of this and other reimbursement changes, the average Medicare reimbursement rate for the nuclear imaging procedures most commonly performed by our physician clients declined by 8.5% from 2006 to 2007, and the average Medicare reimbursement rate for the ultrasound procedures most commonly performed by our physician customers declined by 2% from 2006 to 2007. In July 2007, the Centers for Medicare and Medicaid Services, or CMS, proposed regulations that could result in an additional reimbursement reduction of approximately 10% in 2008 for these procedures. Reimbursement by Medicare for the procedures most commonly performed by our ultrasound imaging customers decreased by 2% for 2007 as compared to 2006, and CMS has proposed additional reimbursement reductions in 2008 for these ultrasound procedures of approximately 18%. An additional proposal, if adopted, would eliminate one commonly used reimbursement code. CMS has also proposed to prohibit physicians and physician groups from “marking-up” the price of professional interpretations of diagnostic imaging they obtain from anyone not a full-time employee of the physician or physician group, such as a part-time group member. If finalized, this proposed reimbursement restriction may provide a disincentive for some physicians to purchase our gamma cameras. CMS has also proposed to prohibit independent diagnostic testing facilities from sharing space, personnel, or equipment with any other imaging suppliers, a proposal that could further prohibit certain existing and new diagnostic imaging arrangements among physician groups and reduce sales of our gamma cameras. Other reimbursement reductions remain under consideration, and we cannot predict whether and to what extent implementation of these reductions will be delayed or whether and how the specific reimbursement rates applicable to procedures performed by our physician clients will be affected. If reimbursement reductions increase, sales of our gamma cameras would suffer and we may receive pressure from our customers to terminate or otherwise modify the lease arrangements for our DIS services. Under such circumstances, our business, financial condition and results of operations could be materially adversely affected. In addition, nuclear medicine is a “designated health service” under the federal anti-self-referral laws known as the Stark Law. Under this law, a physician may not refer to an entity with which the physician or an immediate family member has a financial relationship, unless an exception applies. DIS’ physician customers may be able to meet the “in-office ancillary services” exception to the Stark Law if they meet the definition of a “Group Practice” under Stark, personally supervise the individuals performing the nuclear imaging services and bill for them, and if the services are performed in the same building in which the physicians regularly practice medicine. In July 2007, CMS proposed to modify the Stark regulations in a manner that may restrict physicians in some business arrangements from utilizing the in-office ancillary services exception to Stark. CMS could at any time propose or implement other Stark modifications to limit use of the in-office ancillary services exception. If DIS’ customers are unable or unwilling to comply with the Stark Law, utilization rates of our services and products will decline and our business will be harmed. The potential for adoption of healthcare reform proposals on a state-by-state basis could require us to develop state-specific marketing and sales approaches and adversely affect the results of operations.

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Regulatory changes could have a negative impact on camera sales to and leases with hospitals desiring to use our cameras and services in their outpatient facilities.

In order for hospitals to receive certain payments for their outpatient facilities as hospital outpatient services, including services that utilize our products, these services must be furnished in a “provider-based” organization or facility, or be covered services furnished “under arrangement” with the hospital. Failure to meet these requirements may result in reduced payments to the hospitals for their services. The Medicare program has published and revised rules establishing criteria for classifying a facility as “provider-based” or a service as furnished “under arrangement.” These rules require an analysis of the facts and circumstances surrounding the delivery by a hospital of a particular service, and hospitals that use our products or DIS services in their outpatient facilities will need to determine if they meet the applicable “provider-based” or “under arrangement” requirements. Hospitals that cannot obtain sufficient payments for these services may not purchase a camera from us or enter into arrangements with us for provision of services.

If we fail to comply with various licensure or certification laws, regulations or standards, we may be subject to civil, criminal and/or administrative penalties, which would adversely affect our operations.

All of the states in which we operate require that the imaging technicians operating our cameras be licensed, registered or certified and such licensing, registration and certification requirements are subject to change. Obtaining licenses may take significant time as we expand into additional states or if requirements change. Any lapse in the licensure or certification of our technicians could increase our costs and adversely affect our operations and financial results.

In addition, our DIS nuclear services model involves administering and furnishing radiopharmaceuticals and, until recently, pharmacological stress agents, which are regulated as drugs by state and federal agencies, including the FDA and state pharmacy boards. If a state regulatory authority determines that we have operated our business without required permits or licensure, we could be subject to civil, criminal and/or administrative penalties, including the curtailing or halting of our business. In addition, an inability to obtain required licenses or permits where we currently conduct business, or in states where we plan to expand, would require us to modify the business models we can utilize in the affected jurisdictions. In either case, we could incur substantial expense and could encounter substantial operational burdens.

Our products are subject to reporting requirements and recalls even after receiving FDA clearance or approval, which could harm our reputation, business and financial results.

We are subject to medical device reporting regulations that require us to report to the FDA or similar governmental bodies in other countries if our products cause or contribute to a death or serious injury or malfunction in a way that would be reasonably likely to contribute to death or serious injury. In addition, the FDA and similar governmental bodies in other countries have the authority to require the recall of our products in the event of material deficiencies or defects in design or manufacture that could cause adverse health consequences. A government-mandated or voluntary recall by us could occur as a result of component failures, manufacturing errors or design defects, including defects in labeling. Any recall would divert management attention and financial resources and harm our reputation with customers.

If we fail to obtain, or are significantly delayed in obtaining, FDA or foreign regulatory clearances or approvals for future products or product enhancements, or if we or our third party contractors fail to comply with FDA’s Quality System Regulation, or the quality regulations of foreign governments, our ability to market and distribute our products will suffer.

Our products are subject to rigorous regulation by the FDA and numerous other federal, state and foreign governmental authorities. In the U.S., the FDA regulates virtually all aspects of a medical device’s testing, manufacture, safety, labeling, storage, recordkeeping, reporting, promotion and distribution. Our failure to comply with those regulations could lead to the imposition of administrative or judicial sanctions, including Warning Letters, injunctions, suspensions or the loss of regulatory clearances or approvals, product recalls, termination of distribution, product seizures, injunctions, criminal sanctions or closure of our manufacturing facilities. The process of obtaining regulatory clearances or approvals to market a medical device can be costly and time consuming, and there can be no assurance that such clearances or approvals will be granted on a timely basis, if at all. Commercial distribution of a new medical device generally requires 510(k) clearance or an approved pre-market approval (PMA). The FDA will clear marketing of a medical device through the 510(k) process if it is demonstrated that the new product is substantially equivalent to a legally marketed predicate device. The PMA approval process is more costly, lengthy and uncertain than the 510(k) clearance process, and must be supported by extensive data, including data from preclinical studies and human clinical trials. We cannot assure you that we will receive marketing clearance or PMA approval for any of our new products or product enhancements, or that significant delays in the introduction of any new products or product enhancements may not occur. While we have not been required to obtain PMA approval for any of our products, we may in the future have to undergo the lengthier, burdensome, and expensive PMA approval process. Further, pursuant to FDA regulations, we can only market our products for cleared or approved uses.

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Our manufacturing processes and those of our third-party manufacturers are required to comply with the FDA’s Quality System Regulation, which covers the design, testing, production processes, controls, quality assurance, labeling, packaging, storage and shipping of our devices. In addition, we must engage in extensive recordkeeping and reporting and must make available our manufacturing facility and records for periodic unscheduled inspections by federal, state and foreign agencies, including the FDA. Our failure or our third-party manufacturers’ failure to pass a Quality System Regulation inspection or to comply with these and other applicable regulatory requirements could result in disruption of our operations and manufacturing delays, and a failure to take adequate corrective action could result in, among other things, Warning Letter(s), withdrawal of our medical device clearances, seizure or recall of our devices, or other civil or criminal enforcement actions.

Modifications to our products may require new 510(k) clearances or pre-market approvals, or may require us to cease marketing or recall the modified products until clearances are obtained.

Any modification to a 510(k)-cleared device that could significantly affect its safety or effectiveness, or that would constitute a major change in its intended use, requires a new 510(k) clearance or, possibly, approval of a PMA. The FDA requires every manufacturer to make this determination in the first instance, but the FDA may review any manufacturer’s decision. The FDA may not agree with our decisions regarding whether new clearances or approvals are necessary. If the FDA requires us to seek 510(k) clearance or PMA approval for modification of a previously cleared product for which we have concluded that no clearances or approvals are necessary, we may be required to cease marketing or to recall the modified product until we obtain clearance or approval, and we may be subject to significant regulatory fines or penalties. Further, our products could be subject to recall if the FDA determines, for any reason, that our products are not safe or effective. Any recall or FDA requirement for which we seek additional approvals or clearances could result in delays, fines, costs associated with modification of a product, loss of revenue and potential operating restrictions imposed by the FDA, any of which would harm our business.

Risks Related to Our Financial Results

Our quarterly and annual financial results are difficult to predict and are likely to fluctuate from period to period.

Our revenue and results of operations at any given time will be primarily based on the following factors, many of which we cannot control:

Furthermore, we have experienced seasonality in the leasing services offered by DIS. While our physicians are obligated to pay us for all lease days to which they have committed, our contracts permit some flexibility in scheduling when services are to be performed. This accounts for some of the seasonality of our DIS revenues. We cannot predict with certainty the degree to which seasonal circumstances such as the summer slowdown, winter holiday variations and weather conditions may make our revenue unpredictable or lead to fluctuations in our quarterly operating results in the future.

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In addition, due to the way that customers in our target markets acquire our products, a large percentage of our camera orders is booked during the last month of each quarterly accounting period. As such, a delivery delay of only a few days may significantly impact our quarter-to-quarter comparisons. Moreover, the sales cycle for our cameras is typically lengthy, which may cause us to experience significant revenue fluctuations.

For these reasons, quarterly and annual sales and operating results may vary in the future and period-to-period comparisons of our results of operations are not necessarily meaningful and should not be relied upon as indicators of future performance. We cannot assure you that our sales will increase or be sustained in future periods. We have experienced, and may continue to experience, significant, unanticipated quarterly and annual losses. Because of these and other factors, our operating results in one or more future reporting periods may fail to meet the expectations of securities analysts or investors, which could cause our stock price to decline significantly.

We have incurred significant and recurring operating losses since our inception in 1985 and we may incur such losses and increased operating expenses in the near term.

We have incurred significant cumulative net losses since our inception in November 1985 and may incur such losses and increased operating expenses in the near term as we, among other things, expand our DIS business, increase marketing, sales and distribution of our current products, and conduct research and development to develop next-generation products and to enhance our existing products.

As a result of these activities, we may not be able to become profitable or, if we do, maintain profitability. If our revenue grows more slowly than anticipated, or if our operating expenses exceed our expectations, our ability to achieve our development and expansion goals would be adversely affected.

Risks Related to Our Intellectual Property and Potential Litigation

Our ability to protect our intellectual property and proprietary technology through patents and other means is uncertain.

Our success depends significantly on our ability to protect our proprietary rights to the technologies used in our products. We rely on patent protection, as well as a combination of copyright, trade secret and trademark laws, and nondisclosure, confidentiality and other contractual restrictions to protect our proprietary technology. However, these legal means afford only limited protection and may not adequately protect our rights, be enforceable or permit us to gain or keep any competitive advantage. Our pending U.S. and foreign patent applications, which include claims to material aspects of our products and procedures that are not currently protected by issued patents, may not issue as patents in a form that will be advantageous to us. Any patents we have obtained or do obtain may be challenged by re-examination or otherwise invalidated or eventually found unenforceable. Both the patent application process and the process of managing patent disputes can be time consuming and expensive. Competitors may attempt to challenge or invalidate our patents, or may be able to design alternative techniques or devices that avoid infringement of our patents, or develop products with functionalities that are comparable to ours.

In the event a competitor infringes upon our patent or other intellectual property rights, litigation to enforce our intellectual property rights or to defend our patents against challenge, even if successful, could be expensive and time consuming and could require significant time and attention from our management. We may not have sufficient resources to enforce our intellectual property rights or to defend our patents against challenges from others.

The medical device industry is characterized by patent litigation and we could become subject to litigation that could be costly, result in the diversion of our management’s time and efforts, and require us to pay damages.

Any litigation or claims against us, or claims we bring against others, may cause us to incur substantial costs, could place a significant strain on our financial resources, divert the attention of our management from our core business and harm our reputation. If the relevant patents were upheld as valid and enforceable and we were found to be inadvertently infringing, we could be required to pay substantial damages and/or royalties and could be prevented from selling our products unless we could obtain a license or were able to redesign our system to avoid infringement. Any such license may not be available on reasonable terms, if at all. If we fail to obtain any required licenses or make any necessary changes to our products or technologies, we may be unable to commercialize one or more of our products, which could severely harm our business.

We may be subject to damages resulting from claims that we, or our employees, have wrongfully used or disclosed alleged trade secrets of their former employers.

Many of our employees were previously employed at other medical device companies, including our competitors or potential competitors. Although no claims against us are currently pending, we may be subject to claims that we or our employees have

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inadvertently or otherwise used or disclosed trade secrets or other proprietary information of their former employers. Litigation may be necessary to defend against these claims. Even if we are successful in defending against these claims, litigation could result in substantial costs and be a distraction to management. If we fail in defending such claims, in addition to paying money damages, we may lose valuable intellectual property rights or personnel. A loss of key research personnel or their work product could hinder or preclude our ability to commercialize our products, which could severely harm our business.

Risks Related to the Securities Markets and Ownership of Our Common Stock

Our stock price may be volatile.

The market price for our common stock has been and is likely to continue to be volatile. In addition, the market price of our common stock may fluctuate significantly in response to a number of factors, most of which we cannot control, including:

Future sales of our common stock may cause our stock price to decline.

A small number of our current stockholders hold a substantial number of shares of our common stock that they may sell in the public market. Sales by our current stockholders of a substantial number of shares, or the expectation that such sale may occur, could significantly reduce the market price of our common stock. Moreover, the holders of a substantial number of our shares of common stock, including shares issued upon the exercise of certain of our warrants, have rights, subject to some conditions, to require us to file registration statements to permit the resale of their shares in the public market or to include their shares in registration statements that we may file for ourselves or other stockholders. We have also registered all common stock that we may issue under our employee benefit plans. Accordingly, these shares can be freely sold in the public market upon issuance, subject to restrictions under the securities laws and the lock-up agreements described above. If any of these stockholders cause a large number of securities to be sold in the public market, the sales could reduce the trading price of our common stock. These sales also could impede our ability to raise future capital.

Our common stock is thinly traded and an active trading market may not be sustained.

Although we are currently listed for trading on the Nasdaq National Market, an active trading market for our common stock may not be sustained. An inactive market may impair your ability to sell your shares at the time you wish to sell them or at a price that you consider reasonable. Furthermore, an inactive market may impair our ability to raise capital by selling shares and may impair our ability to acquire other businesses, products and technologies by using our shares as consideration.

Anti-takeover provisions in our organizational documents, our Stockholders Rights Plan and Delaware law may prevent or delay removal of current management or a change in control.

Our restated certificate of incorporation and restated bylaws contain provisions that may delay or prevent a change in control, discourage bids at a premium over the market price of our common stock and adversely affect the market price of our common stock and the voting and other rights of the holders of our common stock. These provisions include:

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The rights issued pursuant to our Stockholder Rights Plan will become exercisable, subject to certain exceptions, the tenth day after a person or group announces acquisition of 15% or more of our common stock or announces commencement of a tender or exchange offer the consummation of which would result in ownership by the person or group of 15% or more of our common stock.

In addition, as a Delaware corporation, we are subject to Delaware law, including Section 203 of the Delaware General Corporation Law. In general, Section 203 prohibits a Delaware corporation from engaging in any business combination with any interested stockholder for a period of three years following the date that the stockholder became an interested stockholder unless certain specific requirements are met as set forth in Section 203.

These provisions alone or together, could have the effect of deterring or delaying changes in incumbent management, proxy contests or changes in control.

If our officers, directors and principal stockholders choose to act together, they may be able to control our management and operations, acting in their best interests and not in the best interests of other stockholders.

Our officers, directors and holders of 5% or more of our outstanding common stock beneficially own a significant amount of our outstanding common stock. As a result, these stockholders, acting together, will be able to significantly influence all matters requiring approval by our stockholders, including the election of directors and the approval of mergers or other business combination transactions. The interests of this group of stockholders may not always coincide with our interests or the interests of other stockholders, and they may act in a manner that advances their best interests and not necessarily those of other stockholders. As a result of their actions or inactions our stock price may decline.