Severe diffuse proliferative bronchiolitis complicating culture-proven disseminated BCG infection after intravesical instillation for bladder cancer.

A man in his 70s was admitted to hospital following several months of dyspnoea, night sweats, weight loss and, latterly, fevers. His symptoms correlated with a second maintenance cycle of intravesical BCG instillation for superficial bladder cancer. Blood tests showed raised C-reactive protein, alkaline phosphatase and gamma-GT, although extensive further investigations did not reveal any specific cause. Treatment for a presumed diagnosis of disseminated BCG infection was started, following which his fevers ceased. Later available results of liver biopsy taken prior to treatment supported this diagnosis, and mycobacterial blood and urine cultures grew Mycobacterium bovis Recovery was complicated by a severe diffuse proliferative bronchiolitis which responded to corticosteroids. This case highlights an important dichotomy in the pathophysiology of disseminated BCG infection. It demonstrates how morbidity can be caused by both a direct dissemination of the organism and an immune hypersensitivity response in the same patient.

Lessons of the month 1: Longitudinal extensive transverse myelitis following AstraZeneca COVID-19 vaccination.

Longitudinal extensive transverse myelitis (LETM) is a rare but recognised complication of vaccination. We report the case of a 58-year-old man admitted to hospital 10 days after his first AstraZeneca COVID-19 vaccination with progressive neurological symptoms and signs, and investigations and imaging consistent with LETM.This case reviews the literature and the investigative process behind excluding other diagnoses given the patient's background of pulmonary sarcoidosis. It is unique in being the first UK report of a case of LETM with a strong temporal link to COVID-19 vaccination.

The additive prognostic value of coronary calcium score (CCS) to single photon emission computed tomography myocardial perfusion imaging (SPECT-MPI)-real world data from a single center.

AIMS: Single-photon emission computed tomography myocardial perfusion imaging [SPECT-MPI] is a functional test for coronary ischemia. We aimed to assess the additive prognostic value of coronary calcium score (CCS) to SPECT-MPI in stable patients. METHODS: This study is a retrospective analysis of 655 patients who underwent SPECT-MPI with CCS (2012 to 2017). Receiver operator characteristic (ROC) identified CCS cutoff value for all-cause mortality: CCS+ if > cutoff value and MPI+ if ≥ 5% total perfusion defect (TPD). Patients were divided into 1 MPI-/CCS-; 2 MPI+/CCS-; 3 MPI-/CCS+; 4 MPI+/CCS+ and compared. Cox proportional hazard analysis identified predictors of mortality. RESULTS: CCS cutoff for all-cause mortality was > 216 (C statistic 0.756, P < 0.0001). In MPI+ groups, mean TPD was similar (13.4% and 13.1% respectively) but mortality was higher in the CCS+ (12.5% vs. 4.8%, P = 0.22) as was the severe LV systolic dysfunction (8.0% vs. 0%, P = 0.095). In MPI- groups, mean TPD was similar (0.7% and 0.9% respectively) but all-cause mortality was higher in the CCS+ (10.7% vs. 1.6%, P < 0.0001) as was severe LVSD (2.9 % vs. 0.3% P = 0.016). Age, smoking, renal impairment ,and CCS > 216 were independent predictors of mortality. CONCLUSIONS: Patients with raised CCS on SPECT-MPI have increased mortality and poor LV function despite a negative MPI.

Error analysis of collimated and uncollimated SeHCAT retention measurement using a gamma camera.

AIM: There is increasing interest in using collimated gamma cameras for [75Se]tauroselcholic acid (SeHCAT) studies to image the distribution and to make use of the collimator pressure sensitive devices (PSD) for patient safety. However, the use of a collimator will substantially decrease the sensitivity of the gamma camera. The aim of this article is to enable departments to calculate the uncertainty of SeHCAT retention measurements so that the acquisition time can be optimised to perform a reliable SeHCAT study. METHOD: We derive a mathematical equation from the first principles that can be used to calculate the uncertainty in SeHCAT retention measurements on the basis of Poisson counting statistics. The equation takes account of background subtraction, use of the geometric mean for anterior/posterior attenuation compensation and the day 7 to day 0 quotient calculation. RESULTS: Uncertainties in SeHCAT retention measurement using an intrinsic (uncollimated) gamma camera counting for 100 s are very low, typically of the order 15 ± 0.1%. Uncertainties from collimated gamma camera counting significantly increase for the same 100 s counting duration: 15 ± 0.8% for slim patients and 15 ± 4% for obese patients. CONCLUSION: The acquisition time must be increased for collimated gamma camera SeHCAT counting to achieve acceptable counting statistics for an acceptable total uncertainty in the SeHCAT retention measurement. For slim patients, a minimum counting time of 2 min is required. For larger patients, the acquisition time needs to be increased to 30 min and further increased to 50 min for obese patients.

Gastric emptying: methodology and normal ranges for two commonly used meals in the UK.

AIM: A recent audit has highlighted that there is a large variation in the way gastric emptying scintigraphy is performed, analysed and reported in the UK. In this study, we have established a comprehensive protocol on how to perform gastric emptying including normal ranges for two of the most widely used meals. A standardized scrambled egg sandwich was used as the main meal. Normal ranges were also established for oat porridge as an alternative gluten-free meal. We have calculated normal ranges for several functional parameters which may be used to assess gastric emptying. We hope that establishing a reliable normal range for these two simple and commonly used meals will encourage adoption of a universally accepted protocol for measurement of solid gastric emptying in the UK. METHOD: A total of 42 volunteers (20 male, 22 female, age range 22-68) with no history of gastrointestinal symptoms or diabetes were studied. Each volunteer fasted overnight and consumed two meals with similar nutritional composition on two separate days: scrambled eggs with two slices of bread were consumed on one day and gluten-free porridge (40 g in 200 mL whole milk) was consumed on a different day. Each meal was radiolabelled with 10 MBq of Tc-DTPA. Simultaneous anterior-posterior 2-min static images were acquired with the patient standing between the gamma camera detectors. Images were acquired every 5 min over a 2 hour period, followed by a single image at 3 hour. The data were modelled using a power-exponential function that allowed measurements of gastric emptying functional parameters including lag time, half-emptying time (HET), peak emptying rate, time-to-peak emptying (TPE) and exponential half-life (EHL). Three-hour retention was also calculated. Paired t-tests were used to compare the two meals and two-sample t-tests were used to assess gender-related differences. Regression analysis was used to assess correlation of the functional parameters with age and body habitus (body surface area, BSA). RESULTS: All gastric emptying functional parameters were significantly different between the two meals (P < 0.001). The normal range for lag time was 0-13 min for porridge and 1-34 min for scrambled egg. The normal range for HET was 18-73 min for porridge and 44-116 min for scrambled egg. The normal range for EHL was 21-57 min for porridge and 20-82 min for scrambled egg. The normal range for 3 hour retention was <7% for porridge and <17% for scrambled egg. Only weak significance was found for gender-related differences in gastric function for the two meals (0.05 < P < 0.10). Weak correlation was also observed for some functional parameters when plotted against age and BSA (0.05 < P < 0.10). CONCLUSION: We have established gastric emptying normal ranges for the two most commonly used meals in the UK. The normal ranges are meal specific and not interchangeable, with porridge showing significantly faster transit than scrambled egg for all measured parameters. Scrambled egg sandwich is the recommended meal for solid gastric emptying studies as it is more reproducible and more comparable to a normally consumed solid meal for our population. Porridge would be a suitable alternative for patients who are unable to eat egg sandwiches, for example, patients with egg allergy or gluten intolerance.

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.

National survey of gastric emptying studies in the UK.

AIM: This study was undertaken to investigate the extent of variation in meals, radiopharmaceuticals and methodology used for gastric emptying studies in the UK. MATERIALS AND METHODS: Overall, 178 nuclear medicine departments across the UK were contacted by telephone and the gastric emptying protocol was requested. In all, 128 (72%) performed routine gastric emptying studies; 83 protocols were received. RESULTS: Liquid meal gastric emptying: 15 departments performed liquid gastric emptying either as a dual isotope technique (27%) or as a separate test using Tc-diethylenetriamine pentacetic acid (53%) or Tc-colloid (20%). The radiopharmaceutical was administered in a variety of liquid mediums including water, orange juice/squash or milk. Although dynamic acquisition was most often used for liquid gastric emptying (60%), significant number of departments used static images (40%). Solid meal gastric emptying: Tc was the radioisotope most predominantly used for solid meals (98%). Tc-colloid was the most commonly used radiopharmaceutical (38%), followed by macroaggregated albumin (25%) and diethylenetriamine pentacetic acid (23%). Egg-based meals are most popular (59%) followed by porridge (27%) that was also used as an alternative to egg in some departments. Alternative meals (cooked meals, ready meals, All-Bran, Weetabix, etc.) were used in 22% of the surveyed departments. Patient preparation and positioning: There was a wide range in patient preparation and methodology used. Patients fasted between 2 and 12 h for the test. Overall, 55% departments acquire images with patient sitting or standing. Although 45% of the departments acquired images supine, most allowed patients to stand or walk in between the images, and only 22% performed the entire test with patient supine. Acquisition parameters: 58% of departments used intermittent static images with intervals ranging from 5 to 15 min, followed by hourly static images of up to 4 h. Twenty-five per cent of departments used dynamic acquisition images. Seventeen per cent of departments used a combination with early dynamic study followed by static images. Normal ranges: There was a wide variation in the normal ranges used for reporting. Most departments used 50% emptying time to assess gastric function. The maximum normal range values for solid gastric emptying ranged from 60 to 120 min, with four departments relying on the percentage of activity remaining at 4 h (normal<10%). Liquid gastric emptying also had a wide range of values for the normal range. The most commonly used range for liquid gastric emptying was 40-60 min. CONCLUSION: There is a wide variation in radiopharmaceuticals, meals and the methodology used for gastric emptying studies. Solid meal gastric emptying is performed universally by all the departments, while relatively few performed liquid meal gastric emptying. Our survey shows that egg-based meals are most prevalent, followed by a porridge meal. Intermittent static imaging is also the most popular method of imaging. In view of this audit, it would be prudent to establish a protocol for solid meal gastric emptying on the basis of the most commonly used meals and methods that may then be universally acceptable. We propose to undertake a study to establish normal ranges for these meals (egg meal and porridge), using the most accepted imaging methodology in an attempt to establish a standardized normal range and acquisition method for solid gastric emptying studies in the UK.

Pitfalls and Limitations of Radionuclide Hepatobiliary and Gastrointestinal System Imaging.

Radionuclide imaging for the hepatobiliary and gastrointestinal system covers a wide range of different indications and imaging techniques. This wide variety allows the different functional assessments of both systems. Therefore, the understanding of each technique and its indications is essential. Cholescintigraphy is a well-established method in the assessment of acute and chronic cholecystitis. It also has a role in the detection of biliary atresia. The assessment of gastrointestinal transit is also well-established in radionuclide imaging for functional investigation of the gastrointestinal tract. Furthermore, detection of acute gastrointestinal bleeding with radionuclide imaging is also standard practice. This article aims to review the pitfalls and limitations in all of these areas.

Measuring SeHCAT retention: a technical note.

TauroH-23-((75)Se)selena-25-homocholic acid (SeHCAT) retention has been used for the diagnosis of bile acid malabsorption since the early 1980s. Bile acid malabsorption has been increasingly recognized as an important cause of severe chronic diarroea with subsequent increase in the number of referrals for the SeHCAT test. In this study, we review and discuss the standard techniques for the measurement of SeHCAT retention and describe a simple and modified technique using a noncollimated whole-body scanner, suitable for most modern dual-headed cameras.

Acquiring diagnostic DaTSCAN images in claustrophobic or difficult patients using a 180 degrees configuration.

BACKGROUND: In this study, we have investigated the feasibility of a 180 degrees DaTSCAN brain SPECT acquisition. This technique has the advantage of being 'open view' for the patient and therefore more acceptable for claustrophobic patients. It also enables easier access for a technologist to hold the patient's head during acquisition to reduce movement in confused patients or in those with severe tremor. METHODS: In the first part of this study, we validated the practicality and image quality of a 180 degrees acquisition using a DaTSCAN Alderson head phantom with different camera configurations on GE Infinia and Philips AXIS gamma cameras. The effect on image quality of using half the acquisition time was also assessed. In the second part of the study, 50 sets of patient data were reprocessed by reconstructing half of the 360 degrees data to mimic a single-head 180 degrees acquisition. The 180 degrees images were then compared with 360 degrees images for the same patient using a visual score system. The effect of half-time 180 degrees data acquisition on quantification was also assessed using GE QuantiSPECT software. RESULTS: All phantom images from 180 degrees acquisitions contained some degree of distortion at the periphery, but clearly retain the presence of centrally positioned caudate and putamen; hence 180 degrees acquisitions were deemed to produce clinically useful diagnostic images. The shorter (half) acquisition time leads to noisier but acceptable images for all configurations. In the patient study, there was complete agreement between the two reporters with no clinical difference in the diagnostic accuracy between the 180 degrees and 360 degrees images. However, 6 of 50 180 degrees images were marked as poor quality but reportable, compared with 0 of 50 in 360 degrees images. Quantification gave consistently lower nuclei to background ratio values for 180 degrees compared with 360 degrees for normal and abnormal patients. CONCLUSION: It is possible to obtain diagnostic DaTSCAN images using 180 degrees acquisition in difficult patients. The total length of the study may also be shortened by half using L-mode or V-mode camera head configuration.

Pharmacological stress myocardial perfusion scintigraphy: use of a modified adenosine protocol in patients with asthma.

BACKGROUND: Stress radionuclide myocardial perfusion scintigraphy (MPS) using adenosine pharmacological vasodilatation is the preferred method in many centres because of its convenience, safety and speed. It can, however, cause bronchospasm and hence its use is avoided in patients with known or suspected bronchospasm. Owing to service pressures, we use technologist-led adenosine stressing for patients referred for MPS studies. We use a modified adenosine infusion protocol under medical supervision for patients with asthma to prevent and minimize adenosine-induced bronchospasm. In this study, we audited our use of this modified protocol in asthmatic patients and compared the side-effect profile with the standard adenosine protocol used in nonasthmatic patients. METHODS: We audited 50 consecutive patients with asthma attending our department for stress MPS. All patients were taking regular inhalers+/-oral steroids. Patients who had exacerbation of asthma requiring hospital admission during the preceding 6 months were excluded. Before commencing the infusion, two inhaled puffs of salbutamol were administered. A modified adenosine infusion protocol was used, starting initially at a rate of 70 microg/kg/min and increasing to the standard 140 microg/kg/min within 1 min and then maintained for a further 5 min. Technetium-99m tetrofosmin was injected at 3 min. Blood pressure (BP), pulse rate (PR), oxygen saturation and ECG were monitored before, during and at the end of the infusion. All side effects were recorded. Fifty-eight consecutive patients without asthma were included as controls and received the standard 140 microg/kg/min infusion over 6 min. RESULTS: One hundred and eight patients, 50 with asthma and 58 without asthma, were entered into the study. The test was stopped early in two patients (4%) with asthma and 11 patients (19%) without asthma (chi=5.679; P=0.017). Proportionally, more nonasthmatics developed shortness of breath (SOB) (47 of 58, 81% without asthma vs. 35 of 50, 70% with asthma); however, this did not reach statistical significance (chi=1.788, P=NS). Three out of 50 (6%) patients in the asthma group experienced severe SOB but only one of those 50 patients (2%) developed bronchospasm, manifesting as wheeze. In the nonasthma group, five of 58 patients (8.6%) experienced severe SOB but none developed a wheeze. Less flushing (16 of 50, 32% vs. 36 of 58, 62%; P=0.002), dizziness (12 of 50, 24% vs. 26 of 58, 45%; P=0.023) and neck/throat pain (5 of 50, 10% vs. 16 of 58, 28%; P=0.021) was observed in the modified infusion group with asthma compared with the standard infusion group without asthma. Statistical significance was observed in these three side effects. No significant difference in other side effects was noted. A similar decrease in mean diastolic BP, and an increase in mean PR were observed during the infusion in both asthmatic and nonasthmatic groups. The mean systolic BP decreased significantly in nonasthmatic patients (P<0.001) but not in the asthmatic group. No significant change in oxygen saturation was seen during infusion in the asthmatic group. CONCLUSION: The modified adenosine infusion protocol with salbutamol premedication can be used in patients with asthma. This protocol resulted in fewer side effects and changes in BP and PR in asthmatic patients compared with nonasthmatic patients who received the standard adenosine infusion.

Improved body-outline imaging technique for localization of sentinel lymph nodes in breast surgery.

UNLABELLED: Many centers use techniques for localizing the sentinel lymph node (SLN) associated with a breast tumor. Protocols involve the use of an intraoperative probe and blue dye but may or may not include scintigraphy. METHODS: Three methods of body-outline imaging were investigated to aid SLN localization. Body outlines were acquired using a handheld source; a transmission image was acquired from a (57)Co-flood source; and, finally, a new method is described using a (153)Gd-line source attenuation correction for body outline. RESULTS: Method 1 images were of low quality, although 83% of SLNs were visualized. Body outline was unsatisfactory for surgical localization. Method 2 was unsatisfactory because of the lack of a lateral image. Method 3 enabled good presurgical visualization of the SLN (73%) and speeded surgical localization. CONCLUSION: The (153)Gd-line source consistently gives optimal-quality body-outline images. This source is simple, quick, and clearly locates the SLN on multiple projections.