Whole-body single photon emission computed tomography/computed tomography for assessment of oncological bone disease - is an extended field of view (from vertex to toes) of clinical value?

OBJECTIVES: Whole-body single photon emission computed tomography/computed tomography (WB-SPECT/CT) is useful for diagnosing bone metastases. When performed on a dual-headed gamma camera, this may cover from clavicles to proximal femurs due to time constraints. In contrast, the novel 360 o cadmium-zinc-telluride scanner can perform WB-SPECT/CT (from vertex to toes) in approximately 20 min. The aim was to assess the prevalence of additional findings above the clavicles and below the lesser trochanters and the prevalence of incidental findings in the CT component. METHODS: Retrospective study of 117 WB-SPECT/CT scans for oncological bone assessment over a 4-month-period. Scan analysis was performed by two independent experienced radionuclide radiologists. RESULTS: The male:female ratio was 71:46 and the mean patient age was 68 years. The primary malignancies were predominantly prostate 65/117 (55.6%) and breast 40/117 (34.2%). There were additional findings of malignancy above the clavicles in 16/116 scans (13.8%) and below the lesser trochanters in 16/117 scans (13.7%). Two cases in the 'above the clavicles' group were suspected solitary metastases, whereas four cases in the 'below lesser trochanters' group were bone metastases at risk of pathological fracture. Incidental findings of clinical significance included suspected new malignancy in 11/117 (9.4%). CONCLUSION: A WB-SPECT/CT (from vertex to toes) oncological bone protocol is useful for the detection of additional findings of clinical significance above the clavicles and below the lesser trochanters. Reviewing and reporting the CT findings in SPECT/CT is important.

Diagnostic value of single-photon emission computed tomography-CT foot and ankle studies.

AIM: The aim of this study is to determine the impact of foot and ankle single-photon emission computed tomography (SPECT) CT on patient management. METHOD AND MATERIALS: A retrospective review over a 7-year period investigating whether the study identified or confirmed a source of symptoms. The electronic patient record was reviewed to see whether the test was helpful to the onward management of the patient. RESULTS: In total 44 patients were included and pathology was identified in 40 of the 44 patients, with four having normal studies. SPECT CT was deemed helpful in the management of 39 of the patients with the positive usefulness overall calculated as 89%. The remaining five patients where the test was not helpful have been discussed. CONCLUSION: SPECT-CT is a helpful imaging test in the diagnosis of foot and ankle disorders with 89% of studies being diagnostically useful.

British Nuclear Medicine Society Clinical Guideline for bone scintigraphy.

This guideline must be read in conjunction with the British Nuclear Medicine Society (BNMS) Generic guidelines. The purpose of this guideline is to assist specialists in Nuclear Medicine and Radionuclide Radiology in recommending, performing, interpreting and reporting the results of bone scintigraphy studies. This guideline could also be used to help individual departments formulate their own local protocols. This does not aim to be prescriptive regarding technical aspects of individual camera acquisitions, which should be developed in conjunction with the local medical physics expert.

Report of the 2020 British Nuclear Medicine Society survey of nuclear medicine equipment, workforce and workload.

The British Nuclear Medicine Society (BNMS) survey represents the only resource that brings together detailed information on equipment, workforce and workload from the practice of nuclear medicine in the UK. This article is a report of the most recent BNMS survey which was collected during 2019 and 2020. The survey used two methods to collect data: for equipment and workforce, participants created or updated existing online records; for workload information, respondees were asked to submit 12 months of data from local radiology information systems. Following the survey, the BNMS database contained a total of 191 sites (63% of known sites) having either equipment or workforce data or both. In total 39 centres provided workload data which included over 175 000 examinations. A combination of automated tools and visual inspection were used to clean, sort and validate submitted data into formats that allowed further analysis and extraction of useful parameters. Results are presented that the authors believe may be useful for nuclear medicine professionals and other stakeholders. Potential applications include benchmarking for service review and equipment replacement/updating. The survey represents a valuable resource that might be used by the BNMS secretariat to respond to specific queries from BNMS members.

Non-prostate uptake on 18F-PSMA-1007 PET/CT: a case of myeloma.

Prostate-specific membrane antigen (PSMA), a glycoprotein that is highly expressed in prostate cancer, has been used as a target for molecular radiotherapy as well as imaging. Over the last couple of years, 18F-PSMA gained popularity due to its longer half-life (110 min) compared to gallium 68Ga-PSMA (68 min). This has helped the dissemination beyond large metropolitan centres. In addition, due to the low background activity in the urinary bladder (1.2% injected dose over 2 h compared to 10% injected dose over 2 h for 68Ga), 18F-PSMA helps detect local recurrence or spread to pelvic nodes more readily as lesions are not masked by physiological urinary excretion. Despite excellent sensitivities of PSMA positron emission tomography modalities, it is noteworthy that PSMA expression is not specific to the prostate. A variety of normal tissues express PSMA with intense uptake noted in salivary glands, lacrimal glands, the liver, spleen, pancreas, small intestine, bladder and renal cortex. In this case report, we describe an example of non-prostatic PSMA uptake in a patient imaged with 18F-PSMA-1007 positron emission tomography/CT that showed an avid lytic lesion in manubrium. The patient was subsequently proven by biopsy to have myeloma. Our case report illustrates a potential pitfall when imaging patients with 18F PSMA-1007 and adds to the growing body of literature of non-prostatic uptake of PSMA and highlights the need for reporters to be aware of this uptake.

Prostate cancer bone metastases confined to the distal left lower limb.

Bone metastases from prostate cancer most commonly affect the axial and proximal appendicular skeleton with rare involvement of the distal limbs. We describe a case of multiple bone metastases confined to the left lower limb in a patient with biochemical recurrence of prostate cancer. Following an initial post-operative PSA rise, the patient received a course of salvage radiotherapy to the pelvis, however, the PSA level continued to rise and two consequent staging CT scans were negative for local recurrence and metastatic disease. Subsequent development of left ankle pain and swelling led the patient to present to his General Practitioner, which triggered a series of imaging investigations that revealed isolated left lower limb bone metastases. This case report highlights the need to consider peripheral limb bone metastases in patients with biochemical recurrence of prostate cancer, particularly in the setting of a negative staging CT scan and/or bone pain.

Comparing the patient experience between a novel 360° gamma camera (VERITON-CT) and a conventional dual head gamma camera.

Aims: To explore whether the novel 360° gamma camera design of VERITON-CT adversely affects the rate of scan non-completion due to claustrophobia or other patient experience factors, when compared to a standard dual-headed gamma camera. Methods: Single centre prospective study of all nuclear medicine studies on either of two gamma cameras; the VERITON-CT (Spectrum Dynamics Medical) and Discovery NM/CT 670 (GE Healthcare). It was recorded whether the patient had completed the scan as protocoled or, due to claustrophobia, had a shortened scan or no scan. The patients were also offered a patient experience questionnaire, with domains of comfort, scan time, scan noise and claustrophobia assessed using a five-point Likert scale. Results: Over a four-month period, there were 296 patients scanned on the Discovery scanner and 274 patients scanned on the VERITON-CT scanner. There was a scan non-completion rate, due to claustrophobia, of 1.35 % for the Discovery and 1.46 % for the VERITON-CT scanner. 354/570 (62%) of all patients involved returned their questionnaires. There was no statistical difference between the responses for comfort, scan time, scan noise and feelings of claustrophobia. Conclusion: The study provides evidence that the novel 360° gamma camera design of VERITON-CT does not lead to a significantly increased scan failure rate due to claustrophobia and there is no change in the subjective experience for patients.

Interobserver Agreement in the Diagnosis of Parkinson Disease with Cardiac 123I-Metaiodobenzylguanidine Scintigraphy.

The aim of this study was to analyze the interobserver agreement of visual and quantitative assessment of cardiac 123I-metaiodobenzylguanidine scintigraphy. Methods: Planar images were acquired using a low-energy collimator. The heart-to-mediastinum (HM) ratio was adjusted for the use of a low-energy collimator, using a published formula. Interpretation was undertaken both visually and after the addition of adjusted HM ratios. Image findings were classified as normal, abnormal, or borderline. Results: The cohort consisted of 10 patients. On visual interpretation only, there was strong agreement on the interpretation of the scan (κ = 0.82, P < 0.01). Adjusted HM ratios led to a significant increase in mean ratios (1.79 vs. 1.36, P = 0.02) and, when utilized in reporting, resulted in perfect agreement (κ = 1.0, P < 0.01). Conclusion: The use of quantified HM ratios adjusted for low-energy collimator use improves on visual assessment alone and allowed for excellent interobserver agreement.

Impact of COVID-19 on nuclear medicine in the UK.

PURPOSE: COVID-19 brought about unprecedented challenges to healthcare, with nuclear medicine (NM) being no exception. The British Nuclear Medicine Society (BNMS) COVID-19 survey assessed the impact of the first wave of pandemic on NM services in the UK. With COVID-19 resurge compounded by seasonal winter pressures, we reflect and share lessons learnt from the first wave of pandemic to guide future strategy. METHODS: A questionnaire consisting of 34 questions was sent out to all BNMS members over 2 weeks in May 2020, to evaluate the impact of 'lockdown'. RESULTS: One hundred thirty-eight members (92 sites) from a multidisciplinary background responded. There was a 65% reduction across all services; 97.6% of respondents reported some reduction in diagnostic procedures and 71.3% reduction in therapies; 85% worked with a reduced workforce. The North East of England, Greater London and South East and Wessex were most affected by staff absences. The North East reported the highest number of COVID-19 positive staff; London reported the greatest lack of testing. The reported time required to clear the backlog was 1-12 months. Seventy-one percent of participants used BNMS COVID-19 guidance. CONCLUSION: The first wave caused a major disruption of NM service delivery and impacted on the workforce. The departmental strategies should tailor services to evolving local and regional differences in prevalence of COVID-19. A blanket shutdown of services with a 'one size fits all' strategy would likely have a severe impact on future delivery of NM and health services in general. Timely testing of staff and patients remains of paramount importance.

The Effect of an Asymmetric Energy Window on Bone Scintigraphy Image Quality.

Bone scintigraphy is one of the most common nuclear medicine tests. Previous work investigated the effectiveness of an asymmetric window (ASW) for planar bone scintigraphy using simulation and phantom data. Phantom studies concluded that the ASW improved both the resolution and the contrast-to-noise ratio when imaging objects with high scatter. The aim of this study was to confirm this improvement increased image quality in patients. This study also investigated whether the differences between a symmetric window (SW) and an ASW depended on body mass index. Methods: Fifty-eight patients had 2 scans: a standard scan using an SW of 140 keV ± 10% and a scan using an ASW of 140 keV + 10% and - 7.5%. Three readers independently compared the 2 image sets and scored them using a 5-score scale (ranging from 1 = ASW better [clinically important] to 5 = SW better [clinically important]). Scores from all radiologists were pooled and analyzed statistically. A P value of less than 0.05 was considered statistically significant. Results: In 93 cases (53%), the readers scored the ASW images better than the SW images. In 5 cases (3%), the ASW images were preferred, with the difference considered clinically important; there were no cases in which the SW was similarly preferred. For the sign test, we determined whether the total of 93 scores of 1 or 2 (ASW preferred) was significantly different from the 15 scores of 4 or 5 (SW preferred). The P value was less than 0.00001, demonstrating that the difference was significant. Conclusion: In patients undergoing bone scintigraphy, ASW provided an improvement in image quality that in some cases was judged clinically important.

Pleural, pancreatic and prostatic involvement in IgG4-related disease mimicking pancreatic head malignancy.

We describe the case of a gentleman with pleural thickening. On follow-up imaging, dilatation of the main pancreatic and common biliary ducts was noted and an initial diagnosis of pancreatic malignancy was made. During his preoperative workup for pancreatic head malignancy, a PET-CT was performed, which demonstrated increased uptake in the pancreas, in the pleura and in the prostate gland. This raised the possibility of immunoglobulin G4-related disease (IgG4-RD), which was effectively treated with oral steroids. IgG4-RD is a well-described cause of autoimmune pancreatitis but can affect other regions, including the pleura and prostate. It is essential that radiologists are aware of the imaging findings in IgG4-RD and can direct clinicians towards this important multisystem diagnosis.

18FDG-PET/CT findings in COVID-19: a single centre retrospective radiological review.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes the infectious disease COVID-19, was declared a global pandemic in March 2020. As radiology departments recommence 18FDG-PET/CT imaging, it is likely that both asymptomatic and specific symptomatic patients with COVID-19 infection will be imaged, particularly if the disease becomes endemic in the UK. We review the clinical scenarios where 18FDG-PET/CT could be performed in COVID-19 positive patients. Our local protocol for safely scanning known COVID-19 positive patients is described, highlighting considerations for other departments. We present the findings from a series of known COVID-19 positive patients and two further asymptomatic cases evaluated with18FDG-PET/CT. Classic, indeterminate, normal and non-COVID-19 manifestations on both the 18FDG-PETand low dose CT component are described as an aid for radiologists and nuclear medicine physicians when reporting 18FDG PET/CT.

COVID-19: guidance for infection prevention and control in nuclear medicine.

This guidance document is a brief consensus document covering the range and breadth of nuclear medicine practice in the UK, and identifies a few steps individual nuclear medicine practitioners and departments can take in the best interests of their patients. This guidance document should be used to inform local practice and does not replace local Trust policies or any relevant legislation. At all times, the best interests of the patients should be paramount. Please read this guidance in conjunction with previous editorial (COVID-19- Nuclear Medicine Departments, be prepared! by Huang HL, Allie R, Gnanasegaran G, Bomanji. J Nucl Med Commun 2020; 41:297-299). Although some aspects of this guidance are time-sensitive due to the nature of the global emergency, we believe that there is still sufficient information to provide some key guiding principles.

Parathyroid scintigraphy.

The purpose of this guideline is to assist specialists in Nuclear Medicine and Radionuclide Radiology in recommending, performing, interpreting and reporting the results of Parathyroid Scintigraphy. This guideline will assist individual departments to formulate their own local protocols. This does not aim to be prescriptive regarding technical aspects of individual camera acquisitions which need to be developed in conjunction with the local medical physics expert. These guidelines pertain only to adult patients. There are numerous techniques for localizing Parathyroid adenomas. This guideline will describe the use of 99mTc-sestamibi dual phase imaging which may be used alone or in combination with other modalities.

Ventilation/perfusion single-photon emission computed tomography: a service evaluation.

OBJECTIVES: To identify the positive rate and negative predictive value (NPV) of our ventilation/perfusion (V/Q) single-photon emission computed tomography (SPECT) service as respective markers of overcalling (false positives) and undercalling (false negatives). We also identified the indeterminate rate as an indicator of the technical quality of the scans and reporter confidence. PATIENTS AND METHODS: V/Q SPECT studies carried out over 5 years were classified into positive, negative and indeterminate results. Patients who had died or had pulmonary emboli on imaging within 3 months of a negative V/Q SPECT were identified as false negatives, from which the NPV was calculated. The total number of positive and indeterminate studies as a proportion of all studies was calculated as the positive and indeterminate rates. RESULTS: The positive rate, NPV and indeterminate rates in nonpregnant patients were 24, 98.7-100 and 3.6%, respectively. The positive rate, NPV and indeterminate rates in pregnant patients were 6.8, 100 and 2.3%, respectively. CONCLUSION: The positive rate and NPV for nonpregnant patients were similar to the published literature. This suggests that we provide a safe service. The indeterminate rate was slightly higher than the stated guidelines. The study shows that the positive rate and NPV are achievable indicators of potential overcalling and undercalling in a V/Q SPECT service.This is also one of the first studies to report a positive rate in pregnant patients undergoing V/Q SPECT that other institutions can use as a standard when evaluating their services.

Local validation of the use of Evolution for Bone for bone SPECT imaging.

PURPOSE: In order to locally validate the technique, a retrospective review of a cohort of randomly selected single-photon emission computed tomography (SPECT) bone scans reconstructed with ordered subsets expectation maximization (OSEM) and Evolution for Bone was undertaken. MATERIALS AND METHODS: Thirty consecutive bone SPECT patient data sets (17 spine, nine pelvis, and four spine and pelvis) were chosen. Poisson resampling was used to simulate reduced count data at 50, 75, and 100% of the original number of counts. Evolution for Bone applied resolution recovery to the reduced count images. All images were compared with the original OSEM images, currently used as the standard for clinical use. A qualitative blinded assessment was made by two independent observers, who assessed for noise, contrast, and resolution. RESULTS: Both radiologists saw an improvement in resolution (P = 0.776), noise (P = 0.007), and image quality with all data sets, compared with images processed purely with OSEM and viewed in Volumetrix. However, they completely disagreed on contrast, as the two radiologists scored contrast differently; however, the results are understandable. CONCLUSION: Images with 50, 75, and 100% of the original counts viewed using Evolution for Bone have improved image quality compared with images processed purely with OSEM and viewed in Volumetrix. Evolution for Bone therefore has great potential in departments for reducing either patient doses, waiting lists, or both.