Considerations in Setting Up a Positron Emission Tomography Center Mathis P. Frick, Naresh C. Gupta, John J. Sunderland, Michael A. Best, Joseph A. Rysavy, and Chyng-Yann Shiue Clinically oriented imaging w i t h position emission tomography (PET) has come of age, Given an adequate referral base and physician interest, a compelling argument can be made at all levels of the review process for setting up a PET program in a clinical setting. PET is expensive. It is obvious that the cost of running a PET service depends heavily on an institution's ability to obtain reasonable financing. Educational institutions have the opportunity to acquire special funding through a variety of sources. On the other hand, money can be expensive for private entrepreneurs. It appears that in the near future PET centers will probably remain at educational institutions or large well-financed community hospitals able to raise
money at reasonable rates until reimbursement issues are better resolved. Finally, the future of clinical PET may hinge significantly on the ability of commercial radiopharmaceutical suppliers to provide regional fluorodeoxyglucose distribution. As an institutional program development, PET offers opportunities by providing unique clinical data aiding the referral pattern. PET may serve as a magnet for recruitment in many areas and may promote interdisciplinary cooperation. A clinical PET center serves both as a model for future and more widespread use of PET and as a training ground for medical personnel. Finally, the unique capabilities of PET may facilitate grant opportunities. Copyright 9 1992 by W,B. Saunders Company
LARGE NUMBER of human studies have een safely conducted with positron emission tomography (PET). For many years, PET has been exclusively a university-based research modality. Development of clinical uses for PET Ihas lagged behind those of other modalities. However, PET can provide unique clinical information in a viable manner with high diagnostic accuracy that affects patient management. Equipment has improved markedly over the last few years. Manufacturers provide user-friendly cyclotrons, radiopharmaceutical delivery systems, and scanners. Even though the term turnkey P E T center seems optimistic, personnel and maintenance requirements have been drastically reduced. Automated synthesis modules for key radiopharmaceuticals such as F-18fluorodeoxyglucose (FDG) and N-13 ammonia are available. Improved scanners provide biochemical information with sufficient morphological detail (resolution of 3 to 7 mm) to be used with computed tomography (CT) and magnetic resonance imaging. These modalities provide structural information that complements PET data. With enhanced equipment and controlled
personnel costs, PET studies are not dissimilar to other high-technology studies. This scenario makes it possible for PET to develop a clinical track record. The clinical setting is the only way to realize the medical potential of PET and to benefit from its large research data base. To project the complete realm of appropriate PET applications, the advantages of PET must be considered in relation to those of other modalities. Each new diagnostic test carves out its specific niche, resulting in some adjustment in other areas. This should reduce use of loweryielding studies. The overall effect is that each modality is used more efficiently in the area in which it performs best. PET is accurate in identifying patients with coronary artery disease and myocardial infarction. Cardiac PET studies pinpoint patients who will benefit from revascularization procedures. In patients with partial complex epilepsy being considered for surgery, PET usually locates the abnormal focus before surgical removal. PET studies yield important diagnostic and prognostic information in the management of patients with brain and other tumors. Such studies can also detect recurrence of tumor often difficult to differentiate from treatment-induced abnormalities. PET may help in differentiating the various forms of dementia, such as Alzheimer's disease, multi-infarct dementia, pseudodementia, Huntington's disease, and Parkinson's disease. In the clinical realm, PET studies have to provide routine answers to important diagnostic questions. Clinical PET
From the Center for Metabolic Imaging, Department of Radiology, Creighton University School of Medicine, Omaha, NE. Address reprint requests to Mathis P. Frick, MD, Creighton University Medical Center, Department of Radiology, 601 N 30th St, Omaha, NE 68131. Copyright 9 1992 by W.B. Saunders Company 0001-2998/92/2203-0004505.00/0 182
Seminars in Nuclear Medicine. Vol XXII, No 3 (July), 1992: pp 182-188
CONSIDERATIONS IN SETTING UP A PET CENTER
may obviate the need for other imaging tests and often reduces the need for unnecessary invasive procedures and/or allows other tests, interventions, or hospital stays to occur more selectively. PLANNING A PET CENTER
Establishing a clinical PET center is a timeconsuming process that includes facility design, equipment selection, financing, staffing, budgeting, licensing, and reimbursement issues. There are several possible configurations of a PET facility: hospital based or free-standing and with or without an on-site cyclotron. The most versatile clinical PET center probably consists of a small cyclotron with an automated synthesis module for commonly used tracers and a whole-body multislice PET scanner. Metabolic studies with FDG obtained from a remote source could be backed up by an on-site dedicated rubidium-82 generator to measure blood flow (for cardiac studies). Considerations differ greatly for research and clinical PET applications. A combined research/clinical center requires a proforma justifying both aspects. Space allocation is guided by the center's mission statement: purely clinical or with a research component. The facility of the Creighton Center for Metabolic Imaging is an example of a free-standing clinical PET center with a research component. A PET facility may be built into an existing nuclear medicine department. This may require as little as 1,500 to 2,000 square feet. In absence of pre-existing space, about 3,500 to 4,500 square feet are needed for minimum requirements. Space planning includes allocation for cyclotron and heat exchange rooms, laboratories, patient preparation rooms, scanner room, viewing area, and administrative support facilities. The cyclotron room is an integral part of the PET center. For the cyclotron room, weight considerations may be substantial. Shielding must be added for unshielded cyclotrons. For self-shielded small cyclotrons, the concrete shield is hydraulically removable, and no additional shielding of the wall in the cyclotron room is required. Maximum radiation levels should be specified in the purchase contract for self-shielded units. Considerations include adequate space to service targetry and cyclotron
183
and provision for proper ventilation. The power and water needs for the cyclotron and airconditioning should be carefully addressed. Cooling is provided by deionized water at a certain required flow rate. Coordinated transport of radiopharmaceuticals and radioactive gases to the "hot lab" for quality assurance and quality control and then to the PET scanner room is required. The cyclotron operator room is close to the cyclotron and can be part of the hot lab. The radiochemistry laboratory or nuclear pharmacy (hot lab) receives the proper quantities of radiopharmaceuticals from the radionuclide delivery system (RDS). The "work horse" radiopharmaceuticals of current clinical PET practice are 18FDG and [13N]ammonia. Some syntheses are controlled by the chemistry process control unit included with the cyclotron. The functioning hot laboratory requires several flow hoods, one or two hot cells, and adequate bench space for chemical procedures, including quality control and quality assurance. For the proper quality assurance, a multichannel analyzer, dose calibrator, and provisions for biogen sterility testing are needed. The latter tasks are usually carried out by a radiopharmacist. After selecting a method for radiopharmaceutical synthesis via automated chemical synthesis modules or computer-assisted robotics, one should decide whether a second automated synthesis module or manual synthesis capability is more appropriate. The list of ancillary equipment is long and costly and includes chromatographs, dose calibrators, and blood gas analyzer. The radiation safety equipment list is also extensive and includes leaded bricks and syringes and monitors, alarms for radiation, general purpose probes, and recording systems for air exhausts. Depending on the mission of the PET center, other chemical and support laboratories are needed, such as a clinical laboratory or a cold or warm laboratory for preparation of additional radiopharmaceuticals or their precursors. Hot and cold lab areas should be separated if possible. For a daily schedule of five clinical studies, approximately 200 mCi of FDG is required. This is within range of production capability of both the cyclotron and the RDS. A typical production run for fluorine-18 (18F)
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yields approximately 600 to 700 mCi. Approximately 80 minutes is needed for completion of the synthesis. Before operation, the mode of radiopharmaceutical dose delivery to the imaging suite should be addressed. Options include manual delivery of the dose or a pneumatic system. Because a large number of patients will be outpatients, it is imperative that a patientfriendly reception area and waiting room is considered. A clinical setting must provide for patient convenience and efficient throughput. In order to assure proper throughput and economic use of the scanner, patient preparation rooms are an absolute necessity. These rooms require medical supplies, monitoring equipment, emergency drug carts, and possibly a cardiac exercise cycle and electrocardiogram machine. The PET scanner room is similar to those for CT. However, the scanner has to be properly shielded. Gas conduit lines should be built into the facility during construction and shielded. Ventilation requirements of gas-type radionuclides are different, and a radioactive gas delivery system is needed. Computer and operator rooms require ample space for computer stations, laser printer, and view boxes. To assure proper throughput capability, several computer workstations for image processing are needed. Possibly, remote sites through fiber optic lines with ethernet should be added. In addition, a prospective data base containing proper patient information is crucial if clinical PET research is anticipated. During the planning and building process, close cooperation of the PET team is impera-
tive. Specialists include radiochemistry and pharmacy experts, health physicists, and nurses. Before the start of operation, previously established performance criteria for equipment (see purchase agreement) have to be validated. These include performance and specific yields of cyclotron, RDS, PET scanner, and radionuclide dose calibrators. The training for the PET center personnel should include both off- and on-site training sessions using experienced instructors. Provisions have to be made for source code and service documentation (following proper maintenance contract agreements for labor and parts and addressing hardware and software upgrades). Patient throughput is one of the most important considerations of a clinical PET center. This requires close cooperation of cyclotron operator, scanner operator, and nurse. Flexibility and designing proper schedules (Fig 1) is invaluable to maintain good throughput of 6 to 12 PET studies on a daily basis. The start-up period is crucial to establish efficient production of FDG batches, proper schedules, practical clinical protocols, and reimbursement scenarios. Those planning to set up a PET center need to satisfy all the relevant regulatory aspects including certificate of need application and state and federal licenses for the cyclotron and for dispensing positron-emitting radiopharmaceuticals--a time-consuming process. ECONOMICS OF PET
Financial analysis for a clinical PET center includes analysis of both direct and indirect
Fig 1. Schedule reflecting eight studies in four patients during an S-hour day,
CONSIDERATIONS IN SETTING UP A PET CENTER
costs. Direct costs relate to equipment and personnel, and indirect costs are based on building maintenance, maintenance contract, and other factors. It has been estimated that a clinical PET center becomes self-supporting at the level of approximately six reimbursable procedures per day during a 5-day week. 1,2Both direct and indirect costs reflect the complexity of the center. It is important to initially establish a clinical performance based on a limited range of procedures. Later, the clinical demand may expand after new indications appear through research programs. One way to provide economic analysis of clinical PET is to calculate the hourly operational costs, dividing the predetermined equipment, personnel, and supply cost into fixed and variable components, especially if the center is not fully dedicated to clinical studies but will also participate in research. This approach allows for charging incremental rates for various uses. Because a typical clinical PET study takes approximately 1 hour to perform, hour and study are used interchangeably. Depending on the number of "paid" hours/studies per working day, an hourly operating cost can be projected. This may be used to arrive at proper charges. Major equipment costs of $4 to $6 million include scanner, cyclotron, and radionuclide delivery system. In the future, it might be possible to buy a scanner for a little more than $1 million. In addition, a cyclotron may supply several scanners with isotopes. This cost could then be shared by several sites. Building costs may exceed $1 million; ours were about $500,000. A lot of support equipment is needed, a fact often overlooked when one starts building a PET center. Ancillary equipment includes hot ceils, surge protectors, monitoring equipment for radiation and environmental control, emergency drug cart equipment, roentgenogram processor, computer workstations, software, and laser printer. "Little" things cost between $10,000 to $50,000, and this can add up to another $250,000 to $350,000. A significant number of personnel is needed to operate a research PET facility. This is different from a modern clinical PET facility. For a clinical center, the minimal requirements are a director/supervisor, an operator for the cyclotron and RDS, scanner operator, a parttime radiochemist/pharmacist, a cardiac nurse,
185
administrative staff, and a part-time maintenance technician. This is a far cry from research PET centers, which require much larger staffs. At Creighton we have the following staff: a PET center director (radiochemist), 1.5 full-timeequivalent (FTE) technologists, 1.5 FTE nurses, an additional radiochemist (cyclotron operator), a part-time pharmacist, and a physicist. As an example, our personnel costs amount to $236,000 for salaries and fringes. Range for personnel cost is between $200,000 and $600,000. Other nonsalary expenses include medical school levy, billing expenses, building lease, utilities, maintenance contracts, and marketing. These costs are variable and may range from $150,000 to over $750,000/y. In realizing a clinical PET center, a crucial factor is the cost of money. The impact of this factor depends on loan amount, interest rates, and duration of loan period. A 10-year loan at $3 million costs between $.42 million (at 7%) and $.58 million (at 15%) annually. For a $7 million loan, the respective amounts are $.98 million and $1.3 million per year. Cheap sources of money may reduce capital requirements significantly and are available to educational institutions. Reducing cost may be achieved by using grants, foundation, or donated money, education bonds, or by leasing the building or certain equipment. Payments may involve "backloading" equipment payment and service contracts. When all is said and done, it still costs in excess of $1 million a year to run a PET center. The cost of running a clinical PET center is recovered mainly through charges to patients and third-party carriers. There usually is a technical fee, an isotope fee, and a professional fee. Cardiac studies may consist of a rest and stress flow study and a metabolic study (billed as two studies at our center). Cardiac scans are thus the most time-consuming and expensive tests at our center. Under our current charge scenario (technical fee $1,200, isotope fee $300, professional fee $250), performing 250 heart scans and an equal number of brain scans generates total charges of about $1.2 million. Assuming approximately 750 scans, collections of 50 cents on the dollar will earn approximately $600,000 in the first year. This reasonable and conservative assumption translates into a firstyear operational loss of at least $500,000. No PET operation is ever expected to break even
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during the first year. In a teaching hospital with support of administration and hospital (through contracts), a clinical PET may be justifiable as promising program development. Three scenarios, including a best case and worst case, are shown in Fig 2. It is clear that in a worst-case scenario, "reasonable" charges and a poor collection ratio requires an enormous or impossible number of scans to break even. THE CREIGHTON EXPERIENCE
We believe that establishing clinical PET offers a unique opportunity for imaging excellence at an institution. A clinical PET center must be capable of accommodating patient throughput of 6 to 12 patients/d. This number is consistent with the goal of cost-efficient, noninvasive screening. An institution with a PET center must have strong representation in the key areas of cardiology, neurology, psychiatry, and oncology. Close extramural and intramural cooperation among various medical specialties is mandatory for success. This requires the creation of interdisciplinary teams to design clinical protocols and to cooperate in clinical PET trials. In addition, other conditions must be met: 1. an appropriate patient base for sufficient referrals of proper indications; 2. a facility and equipment designed for clinical use and throughput; 3. personnel familiar with PET and with a focus on clinical utilization; and 4. institutional support in areas of administration, finance, and marketing.
We realize that PET has to compete successfully and economically with other imaging tests by reducing unnecessary invasive procedures and/or allowing others to be performed more selectively. Our confidence in the future of PET has promoted the establishment of a clinical PET center at Creighton University in Omaha. The Center for Metabolic Imaging serves as an adjunct to structural imaging in patient diagnosis. Based on the extensive body of research data gathered over the last decade, we introduced PET applications with proven efficacy into daily clinical practice. With institutional support from Creighton University for a clinical PET program, the Department of Radiology began planning the Center for Metabolic Imaging in spring 1986. Final approval for the center occurred in fall 1987, and a certificate of need was obtained from state authorities in March 1988. Creighton University is the sole owner of the equipment and has operational responsibility for the PET center through its Radiology Department. The PET center is situated on the grounds of the primary psychiatric teaching hospital (St. Joseph Center for Mental Health) and the combined psychiatric program of Creighton University and the University of Nebraska. The primary acute-care teaching hospital of the Creighton Medical School is located approximately two miles away from the PET unit. The cyclotron is designed to operate efficiently by offering modules for the production of commonly used radiotracers while keeping labor requirements low. The PET center has weather-
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CONSIDERATIONS IN SETTING UP A PET CENTER
187
doses of 13NH3 are produced. Two hot cells have been acquired: One is dedicated for basic research and the other for clinical use. Our CTI/Siemens ECAT 931/08-16 PET scanner has been fully operational over 95% of the time. Creighton's PET center is designed to accommodate both maximum clinical throughput and basic research. In keeping with our intent to use PET for clinical studies, we have performed 3 to 12 PET scans (average 5) during an 8-hour day. Since operations began in December 1989, we have performed more than 2,200 PET studies in over 1,200 patients (Fig 4). The referral patient population is evenly divided between outpatients and inpatients. Since PET tests are expensive, indications for individual PET studies are made carefully. We are performing PET on patients for whom costly interventions are planned that may or may not have the desired outcome and on patients who are expected to have a long hospital stay. We are restricting ourselves to few indications, such as the preintervention determination of myocardial viability. This is in keeping with our philosophy that clinical success of PET depends on documentation of an advantage in diagnostic accuracy that influences patient management in an economically viable fashion.
ized ambulance access to accommodate inpatients from all regional hospitals. Creighton University built the Center for Metabolic Imaging at a cost of $5.3 million, including equipment, facility, and working capital. A local contractor built the facility for $500,000, including architectural and engineering fees, site preparation, and the building. The facility is a one-story, 4,539-square-foot, woodframe construction (Fig 3). Cost overruns amounted to approximately $300,000, mainly in nonscheduled ancillary equipment and cost overruns for the building. The building was financed through a long-term lease agreement. The PET center staff consists of: a director (PhD chemist), one nuclear medicine physician, two chemists (one MSc, one BSc), one physicist (PhD), a part-time pharmacist, 1.5 FTE technologists, 1.5 FTE cardiology nurses, one administrative assistant, and one Siemens field engineer. The entire staff serves both the clinical and research requirements of the center. Our CTI/Siemens 11-MeV cyclotron has been fully operational over 95% of the time. Routinely, over 600 mCi 18F fluoride is produced and then converted to approximately 200 mCi FDG, a sufficient dose for a daily patient schedule. As needed throughout the day, single i Heat Exchange,
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188
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Most cardiac patients undergoing PET have wall motion abnormalities, which we have detected by radionuclide ventriculogram or echocardiogram, or fixed thallium defects. For diagnosis and detection of coronary artery disease, a paired resting and stress ammonia study using adenosine is done. Other main indications for PET have been the evaluation of brain and other tumors before and during treatment, assessment of various forms of dementia, and the study of patients with focal epilepsy refractory to medical treatment. Clinical PET use by specialty has been as follows: cardiology (48.1%), oncology (23.8%), psychiatry (19.5%), and neurology (8.6%). The most commonly performed clinical procedures are FDG brain scans (for focal epilepsy, dementia workup, and other psychiatric disorders) and combined nitrogen~ ammonia/FDG heart studies for the evaluation of myocardial viability. The most rapid growth in our volume has occurred in oncological applications both for staging and grading of various tumors (brain, lung, musculoskeletal, colorectal) and for treatment monitoring. Patient referrals in our region are based on PET's unique imaging applications and the fact that our PET center is the only such facility in the region. Our primary service area covers a population of 1.6 million in Nebraska and western Iowa. This is considered a sufficient number. 3 The demand within the primary service area constitutes approximately 95% of our pa-
Apt May Jtme July Ax~8 Sep Oct Nov Dec
Fig4. NumberofPETscans/mo produced at the Center for Metabolic Imaging since the start of operations,
tient load. Our PET center thus serves as a community resource. Indeed, we have received referrals from all local hospitals. The Creighton PET facility has exceeded its targets for PET volume in the first 2 years and has created charges in excess of $2 million. The revenues from charges are below projection (50%) and are currently at about 30% to 35%. Medicare/ Medicaid will not reimburse for PET studies. Some third-party carriers honor all or part of the PET charges. Some of our revenues are forthcoming through hospital contracts for inpatients. We have achieved initial success in working out payment agreements with some of the larger regional insurance companies and are also receiving payment from smaller commercial carriers. Since its inception in December 1989, the Center for Metabolic Imaging has performed a significant volume of varied clinical PET studies reliably and efficiently while also conducting basic research. We have found PET to be a valuable diagnostic tool for improving patient care. REFERENCES 1. Kessler RM, Partain CL, Price RR, et ai: Positron emission tomography: Prospects for clinical utility. Invest Radio122:529-537, 1987 2. Buonocore E, Hubner KF, Kabalk G: Packaging PET imaging for community medicine. Diagn Imag 6:110-I 15, 1987 3. Hawkins RA, Phelps ME: Clinical PET. Operational cost considerations. Admin Radiol 5:20-26, 1986
money at reasonable rates until reimbursement issues are better resolved. Finally, the future of clinical PET may hinge significantly on the ability of commercial radiopharmaceutical suppliers to provide regional fluorodeoxyglucose distribution. As an institutional program development, PET offers opportunities by providing unique clinical data aiding the referral pattern. PET may serve as a magnet for recruitment in many areas and may promote interdisciplinary cooperation. A clinical PET center serves both as a model for future and more widespread use of PET and as a training ground for medical personnel. Finally, the unique capabilities of PET may facilitate grant opportunities. Copyright 9 1992 by W,B. Saunders Company
LARGE NUMBER of human studies have een safely conducted with positron emission tomography (PET). For many years, PET has been exclusively a university-based research modality. Development of clinical uses for PET Ihas lagged behind those of other modalities. However, PET can provide unique clinical information in a viable manner with high diagnostic accuracy that affects patient management. Equipment has improved markedly over the last few years. Manufacturers provide user-friendly cyclotrons, radiopharmaceutical delivery systems, and scanners. Even though the term turnkey P E T center seems optimistic, personnel and maintenance requirements have been drastically reduced. Automated synthesis modules for key radiopharmaceuticals such as F-18fluorodeoxyglucose (FDG) and N-13 ammonia are available. Improved scanners provide biochemical information with sufficient morphological detail (resolution of 3 to 7 mm) to be used with computed tomography (CT) and magnetic resonance imaging. These modalities provide structural information that complements PET data. With enhanced equipment and controlled
personnel costs, PET studies are not dissimilar to other high-technology studies. This scenario makes it possible for PET to develop a clinical track record. The clinical setting is the only way to realize the medical potential of PET and to benefit from its large research data base. To project the complete realm of appropriate PET applications, the advantages of PET must be considered in relation to those of other modalities. Each new diagnostic test carves out its specific niche, resulting in some adjustment in other areas. This should reduce use of loweryielding studies. The overall effect is that each modality is used more efficiently in the area in which it performs best. PET is accurate in identifying patients with coronary artery disease and myocardial infarction. Cardiac PET studies pinpoint patients who will benefit from revascularization procedures. In patients with partial complex epilepsy being considered for surgery, PET usually locates the abnormal focus before surgical removal. PET studies yield important diagnostic and prognostic information in the management of patients with brain and other tumors. Such studies can also detect recurrence of tumor often difficult to differentiate from treatment-induced abnormalities. PET may help in differentiating the various forms of dementia, such as Alzheimer's disease, multi-infarct dementia, pseudodementia, Huntington's disease, and Parkinson's disease. In the clinical realm, PET studies have to provide routine answers to important diagnostic questions. Clinical PET
From the Center for Metabolic Imaging, Department of Radiology, Creighton University School of Medicine, Omaha, NE. Address reprint requests to Mathis P. Frick, MD, Creighton University Medical Center, Department of Radiology, 601 N 30th St, Omaha, NE 68131. Copyright 9 1992 by W.B. Saunders Company 0001-2998/92/2203-0004505.00/0 182
Seminars in Nuclear Medicine. Vol XXII, No 3 (July), 1992: pp 182-188
CONSIDERATIONS IN SETTING UP A PET CENTER
may obviate the need for other imaging tests and often reduces the need for unnecessary invasive procedures and/or allows other tests, interventions, or hospital stays to occur more selectively. PLANNING A PET CENTER
Establishing a clinical PET center is a timeconsuming process that includes facility design, equipment selection, financing, staffing, budgeting, licensing, and reimbursement issues. There are several possible configurations of a PET facility: hospital based or free-standing and with or without an on-site cyclotron. The most versatile clinical PET center probably consists of a small cyclotron with an automated synthesis module for commonly used tracers and a whole-body multislice PET scanner. Metabolic studies with FDG obtained from a remote source could be backed up by an on-site dedicated rubidium-82 generator to measure blood flow (for cardiac studies). Considerations differ greatly for research and clinical PET applications. A combined research/clinical center requires a proforma justifying both aspects. Space allocation is guided by the center's mission statement: purely clinical or with a research component. The facility of the Creighton Center for Metabolic Imaging is an example of a free-standing clinical PET center with a research component. A PET facility may be built into an existing nuclear medicine department. This may require as little as 1,500 to 2,000 square feet. In absence of pre-existing space, about 3,500 to 4,500 square feet are needed for minimum requirements. Space planning includes allocation for cyclotron and heat exchange rooms, laboratories, patient preparation rooms, scanner room, viewing area, and administrative support facilities. The cyclotron room is an integral part of the PET center. For the cyclotron room, weight considerations may be substantial. Shielding must be added for unshielded cyclotrons. For self-shielded small cyclotrons, the concrete shield is hydraulically removable, and no additional shielding of the wall in the cyclotron room is required. Maximum radiation levels should be specified in the purchase contract for self-shielded units. Considerations include adequate space to service targetry and cyclotron
183
and provision for proper ventilation. The power and water needs for the cyclotron and airconditioning should be carefully addressed. Cooling is provided by deionized water at a certain required flow rate. Coordinated transport of radiopharmaceuticals and radioactive gases to the "hot lab" for quality assurance and quality control and then to the PET scanner room is required. The cyclotron operator room is close to the cyclotron and can be part of the hot lab. The radiochemistry laboratory or nuclear pharmacy (hot lab) receives the proper quantities of radiopharmaceuticals from the radionuclide delivery system (RDS). The "work horse" radiopharmaceuticals of current clinical PET practice are 18FDG and [13N]ammonia. Some syntheses are controlled by the chemistry process control unit included with the cyclotron. The functioning hot laboratory requires several flow hoods, one or two hot cells, and adequate bench space for chemical procedures, including quality control and quality assurance. For the proper quality assurance, a multichannel analyzer, dose calibrator, and provisions for biogen sterility testing are needed. The latter tasks are usually carried out by a radiopharmacist. After selecting a method for radiopharmaceutical synthesis via automated chemical synthesis modules or computer-assisted robotics, one should decide whether a second automated synthesis module or manual synthesis capability is more appropriate. The list of ancillary equipment is long and costly and includes chromatographs, dose calibrators, and blood gas analyzer. The radiation safety equipment list is also extensive and includes leaded bricks and syringes and monitors, alarms for radiation, general purpose probes, and recording systems for air exhausts. Depending on the mission of the PET center, other chemical and support laboratories are needed, such as a clinical laboratory or a cold or warm laboratory for preparation of additional radiopharmaceuticals or their precursors. Hot and cold lab areas should be separated if possible. For a daily schedule of five clinical studies, approximately 200 mCi of FDG is required. This is within range of production capability of both the cyclotron and the RDS. A typical production run for fluorine-18 (18F)
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FRICK ET AL
yields approximately 600 to 700 mCi. Approximately 80 minutes is needed for completion of the synthesis. Before operation, the mode of radiopharmaceutical dose delivery to the imaging suite should be addressed. Options include manual delivery of the dose or a pneumatic system. Because a large number of patients will be outpatients, it is imperative that a patientfriendly reception area and waiting room is considered. A clinical setting must provide for patient convenience and efficient throughput. In order to assure proper throughput and economic use of the scanner, patient preparation rooms are an absolute necessity. These rooms require medical supplies, monitoring equipment, emergency drug carts, and possibly a cardiac exercise cycle and electrocardiogram machine. The PET scanner room is similar to those for CT. However, the scanner has to be properly shielded. Gas conduit lines should be built into the facility during construction and shielded. Ventilation requirements of gas-type radionuclides are different, and a radioactive gas delivery system is needed. Computer and operator rooms require ample space for computer stations, laser printer, and view boxes. To assure proper throughput capability, several computer workstations for image processing are needed. Possibly, remote sites through fiber optic lines with ethernet should be added. In addition, a prospective data base containing proper patient information is crucial if clinical PET research is anticipated. During the planning and building process, close cooperation of the PET team is impera-
tive. Specialists include radiochemistry and pharmacy experts, health physicists, and nurses. Before the start of operation, previously established performance criteria for equipment (see purchase agreement) have to be validated. These include performance and specific yields of cyclotron, RDS, PET scanner, and radionuclide dose calibrators. The training for the PET center personnel should include both off- and on-site training sessions using experienced instructors. Provisions have to be made for source code and service documentation (following proper maintenance contract agreements for labor and parts and addressing hardware and software upgrades). Patient throughput is one of the most important considerations of a clinical PET center. This requires close cooperation of cyclotron operator, scanner operator, and nurse. Flexibility and designing proper schedules (Fig 1) is invaluable to maintain good throughput of 6 to 12 PET studies on a daily basis. The start-up period is crucial to establish efficient production of FDG batches, proper schedules, practical clinical protocols, and reimbursement scenarios. Those planning to set up a PET center need to satisfy all the relevant regulatory aspects including certificate of need application and state and federal licenses for the cyclotron and for dispensing positron-emitting radiopharmaceuticals--a time-consuming process. ECONOMICS OF PET
Financial analysis for a clinical PET center includes analysis of both direct and indirect
Fig 1. Schedule reflecting eight studies in four patients during an S-hour day,
CONSIDERATIONS IN SETTING UP A PET CENTER
costs. Direct costs relate to equipment and personnel, and indirect costs are based on building maintenance, maintenance contract, and other factors. It has been estimated that a clinical PET center becomes self-supporting at the level of approximately six reimbursable procedures per day during a 5-day week. 1,2Both direct and indirect costs reflect the complexity of the center. It is important to initially establish a clinical performance based on a limited range of procedures. Later, the clinical demand may expand after new indications appear through research programs. One way to provide economic analysis of clinical PET is to calculate the hourly operational costs, dividing the predetermined equipment, personnel, and supply cost into fixed and variable components, especially if the center is not fully dedicated to clinical studies but will also participate in research. This approach allows for charging incremental rates for various uses. Because a typical clinical PET study takes approximately 1 hour to perform, hour and study are used interchangeably. Depending on the number of "paid" hours/studies per working day, an hourly operating cost can be projected. This may be used to arrive at proper charges. Major equipment costs of $4 to $6 million include scanner, cyclotron, and radionuclide delivery system. In the future, it might be possible to buy a scanner for a little more than $1 million. In addition, a cyclotron may supply several scanners with isotopes. This cost could then be shared by several sites. Building costs may exceed $1 million; ours were about $500,000. A lot of support equipment is needed, a fact often overlooked when one starts building a PET center. Ancillary equipment includes hot ceils, surge protectors, monitoring equipment for radiation and environmental control, emergency drug cart equipment, roentgenogram processor, computer workstations, software, and laser printer. "Little" things cost between $10,000 to $50,000, and this can add up to another $250,000 to $350,000. A significant number of personnel is needed to operate a research PET facility. This is different from a modern clinical PET facility. For a clinical center, the minimal requirements are a director/supervisor, an operator for the cyclotron and RDS, scanner operator, a parttime radiochemist/pharmacist, a cardiac nurse,
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administrative staff, and a part-time maintenance technician. This is a far cry from research PET centers, which require much larger staffs. At Creighton we have the following staff: a PET center director (radiochemist), 1.5 full-timeequivalent (FTE) technologists, 1.5 FTE nurses, an additional radiochemist (cyclotron operator), a part-time pharmacist, and a physicist. As an example, our personnel costs amount to $236,000 for salaries and fringes. Range for personnel cost is between $200,000 and $600,000. Other nonsalary expenses include medical school levy, billing expenses, building lease, utilities, maintenance contracts, and marketing. These costs are variable and may range from $150,000 to over $750,000/y. In realizing a clinical PET center, a crucial factor is the cost of money. The impact of this factor depends on loan amount, interest rates, and duration of loan period. A 10-year loan at $3 million costs between $.42 million (at 7%) and $.58 million (at 15%) annually. For a $7 million loan, the respective amounts are $.98 million and $1.3 million per year. Cheap sources of money may reduce capital requirements significantly and are available to educational institutions. Reducing cost may be achieved by using grants, foundation, or donated money, education bonds, or by leasing the building or certain equipment. Payments may involve "backloading" equipment payment and service contracts. When all is said and done, it still costs in excess of $1 million a year to run a PET center. The cost of running a clinical PET center is recovered mainly through charges to patients and third-party carriers. There usually is a technical fee, an isotope fee, and a professional fee. Cardiac studies may consist of a rest and stress flow study and a metabolic study (billed as two studies at our center). Cardiac scans are thus the most time-consuming and expensive tests at our center. Under our current charge scenario (technical fee $1,200, isotope fee $300, professional fee $250), performing 250 heart scans and an equal number of brain scans generates total charges of about $1.2 million. Assuming approximately 750 scans, collections of 50 cents on the dollar will earn approximately $600,000 in the first year. This reasonable and conservative assumption translates into a firstyear operational loss of at least $500,000. No PET operation is ever expected to break even
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during the first year. In a teaching hospital with support of administration and hospital (through contracts), a clinical PET may be justifiable as promising program development. Three scenarios, including a best case and worst case, are shown in Fig 2. It is clear that in a worst-case scenario, "reasonable" charges and a poor collection ratio requires an enormous or impossible number of scans to break even. THE CREIGHTON EXPERIENCE
We believe that establishing clinical PET offers a unique opportunity for imaging excellence at an institution. A clinical PET center must be capable of accommodating patient throughput of 6 to 12 patients/d. This number is consistent with the goal of cost-efficient, noninvasive screening. An institution with a PET center must have strong representation in the key areas of cardiology, neurology, psychiatry, and oncology. Close extramural and intramural cooperation among various medical specialties is mandatory for success. This requires the creation of interdisciplinary teams to design clinical protocols and to cooperate in clinical PET trials. In addition, other conditions must be met: 1. an appropriate patient base for sufficient referrals of proper indications; 2. a facility and equipment designed for clinical use and throughput; 3. personnel familiar with PET and with a focus on clinical utilization; and 4. institutional support in areas of administration, finance, and marketing.
We realize that PET has to compete successfully and economically with other imaging tests by reducing unnecessary invasive procedures and/or allowing others to be performed more selectively. Our confidence in the future of PET has promoted the establishment of a clinical PET center at Creighton University in Omaha. The Center for Metabolic Imaging serves as an adjunct to structural imaging in patient diagnosis. Based on the extensive body of research data gathered over the last decade, we introduced PET applications with proven efficacy into daily clinical practice. With institutional support from Creighton University for a clinical PET program, the Department of Radiology began planning the Center for Metabolic Imaging in spring 1986. Final approval for the center occurred in fall 1987, and a certificate of need was obtained from state authorities in March 1988. Creighton University is the sole owner of the equipment and has operational responsibility for the PET center through its Radiology Department. The PET center is situated on the grounds of the primary psychiatric teaching hospital (St. Joseph Center for Mental Health) and the combined psychiatric program of Creighton University and the University of Nebraska. The primary acute-care teaching hospital of the Creighton Medical School is located approximately two miles away from the PET unit. The cyclotron is designed to operate efficiently by offering modules for the production of commonly used radiotracers while keeping labor requirements low. The PET center has weather-
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$
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Fig 2. Break-even scenarios for second year: Volume required to cover cost,
CONSIDERATIONS IN SETTING UP A PET CENTER
187
doses of 13NH3 are produced. Two hot cells have been acquired: One is dedicated for basic research and the other for clinical use. Our CTI/Siemens ECAT 931/08-16 PET scanner has been fully operational over 95% of the time. Creighton's PET center is designed to accommodate both maximum clinical throughput and basic research. In keeping with our intent to use PET for clinical studies, we have performed 3 to 12 PET scans (average 5) during an 8-hour day. Since operations began in December 1989, we have performed more than 2,200 PET studies in over 1,200 patients (Fig 4). The referral patient population is evenly divided between outpatients and inpatients. Since PET tests are expensive, indications for individual PET studies are made carefully. We are performing PET on patients for whom costly interventions are planned that may or may not have the desired outcome and on patients who are expected to have a long hospital stay. We are restricting ourselves to few indications, such as the preintervention determination of myocardial viability. This is in keeping with our philosophy that clinical success of PET depends on documentation of an advantage in diagnostic accuracy that influences patient management in an economically viable fashion.
ized ambulance access to accommodate inpatients from all regional hospitals. Creighton University built the Center for Metabolic Imaging at a cost of $5.3 million, including equipment, facility, and working capital. A local contractor built the facility for $500,000, including architectural and engineering fees, site preparation, and the building. The facility is a one-story, 4,539-square-foot, woodframe construction (Fig 3). Cost overruns amounted to approximately $300,000, mainly in nonscheduled ancillary equipment and cost overruns for the building. The building was financed through a long-term lease agreement. The PET center staff consists of: a director (PhD chemist), one nuclear medicine physician, two chemists (one MSc, one BSc), one physicist (PhD), a part-time pharmacist, 1.5 FTE technologists, 1.5 FTE cardiology nurses, one administrative assistant, and one Siemens field engineer. The entire staff serves both the clinical and research requirements of the center. Our CTI/Siemens 11-MeV cyclotron has been fully operational over 95% of the time. Routinely, over 600 mCi 18F fluoride is produced and then converted to approximately 200 mCi FDG, a sufficient dose for a daily patient schedule. As needed throughout the day, single i Heat Exchange,
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188
FRICK ET AL
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Most cardiac patients undergoing PET have wall motion abnormalities, which we have detected by radionuclide ventriculogram or echocardiogram, or fixed thallium defects. For diagnosis and detection of coronary artery disease, a paired resting and stress ammonia study using adenosine is done. Other main indications for PET have been the evaluation of brain and other tumors before and during treatment, assessment of various forms of dementia, and the study of patients with focal epilepsy refractory to medical treatment. Clinical PET use by specialty has been as follows: cardiology (48.1%), oncology (23.8%), psychiatry (19.5%), and neurology (8.6%). The most commonly performed clinical procedures are FDG brain scans (for focal epilepsy, dementia workup, and other psychiatric disorders) and combined nitrogen~ ammonia/FDG heart studies for the evaluation of myocardial viability. The most rapid growth in our volume has occurred in oncological applications both for staging and grading of various tumors (brain, lung, musculoskeletal, colorectal) and for treatment monitoring. Patient referrals in our region are based on PET's unique imaging applications and the fact that our PET center is the only such facility in the region. Our primary service area covers a population of 1.6 million in Nebraska and western Iowa. This is considered a sufficient number. 3 The demand within the primary service area constitutes approximately 95% of our pa-
Apt May Jtme July Ax~8 Sep Oct Nov Dec
Fig4. NumberofPETscans/mo produced at the Center for Metabolic Imaging since the start of operations,
tient load. Our PET center thus serves as a community resource. Indeed, we have received referrals from all local hospitals. The Creighton PET facility has exceeded its targets for PET volume in the first 2 years and has created charges in excess of $2 million. The revenues from charges are below projection (50%) and are currently at about 30% to 35%. Medicare/ Medicaid will not reimburse for PET studies. Some third-party carriers honor all or part of the PET charges. Some of our revenues are forthcoming through hospital contracts for inpatients. We have achieved initial success in working out payment agreements with some of the larger regional insurance companies and are also receiving payment from smaller commercial carriers. Since its inception in December 1989, the Center for Metabolic Imaging has performed a significant volume of varied clinical PET studies reliably and efficiently while also conducting basic research. We have found PET to be a valuable diagnostic tool for improving patient care. REFERENCES 1. Kessler RM, Partain CL, Price RR, et ai: Positron emission tomography: Prospects for clinical utility. Invest Radio122:529-537, 1987 2. Buonocore E, Hubner KF, Kabalk G: Packaging PET imaging for community medicine. Diagn Imag 6:110-I 15, 1987 3. Hawkins RA, Phelps ME: Clinical PET. Operational cost considerations. Admin Radiol 5:20-26, 1986
