Experiences of Nuclear Medicine Technologists Working in PET/CT Facilities in Gauteng Province, South Africa.

The introduction of PET/CT requires staff training, redesign of patient workflow, new skills, problem-solving abilities, and adjustments to radiation protection protocols. When PET/CT was introduced in the U.K., nuclear medicine technologists (NMTs) encountered challenges in defining their roles and unfamiliarity with the new technology and the new working procedures. Since the introduction of PET/CT in South Africa, the experiences of NMTs with this hybrid imaging device have not yet been described. Therefore, the aim of this research study was to explore and describe the experiences of NMTs working in PET/CT facilities in Gauteng Province, South Africa. Methods: This study had a qualitative, exploratory, descriptive design and used a phenomenologic research approach. Semistructured interviews were conducted to collect data until data saturation was reached. A software program was used to manage the codes, categories, and themes. Nine NMTs participated in the study: 5 from public hospitals and 4 from private hospitals. Their age range of 27-58 y provided the ideal heterogeneity for sharing experiences in working in PET/CT facilities. Results: Two overarching themes emerged from the categories: the perspectives of NMTs working in PET/CT facilities and the PET/CT challenges encountered by NMTs. The results suggest that NMTs experience joy and fulfilment from working in PET/CT facilities and regard PET/CT as the future of nuclear medicine. However, NMTs also experience a gap in PET/CT training and are concerned about the high radiation exposure associated with PET/CT imaging and about the lack of psychologic support. Conclusion: Although the NMTs enjoy working in PET/CT, they desire additional clinical training and psychologic support. Since radiation exposure in PET/CT is higher than in general nuclear medicine, radiation monitoring is imperative to minimize exposure to NMTs and patients.

68 Ga-nitroimidazole PET/CT imaging of hypoxia in tuberculosis: A case series.

Tuberculosis (TB) lesions in humans have been proven to be severely hypoxic with hypoxia leading to latency and dormancy of disease. Dormant TB lesions become less susceptible to standard TB treatment regimens with varying responses to treatment but may have increased susceptibility to nitroimidazole drugs. This in turn implies that positron emission tomography / computed tomography (PET/CT) imaging with radiolabelled nitroimidazoles may identify patients who will benefit from treatment with antimicrobial agents that are active against anaerobic bacteria. This case series aims to highlight the hypoxic uptake and retention of a novel 68 Ga-labelled hypoxia-seeking agent in TB lesions at different time points during anti-TB therapy using PET/CT imaging. Patients with confirmed TB underwent whole-body PET/CT after administration of a 68 Ga-nitroimidazole derivative at baseline and follow-up. Images were analysed both qualitatively and semi-quantitatively. Hypoxic uptake and change in uptake over time were analysed using lesion-to-muscle ratio (LMR) and lesion-to-blood ratio (LBR). 68 Ga-nitroimidazole avid lesions were demonstrated most frequently in the upper lobes of the lung. Low-grade hypoxic uptake was visualised in areas of consolidation, cavitation, nodules and lymph nodes. From baseline to follow-up imaging, the LMR increased with persistent hypoxic load despite morphologic improvement. This case series highlights the dynamic hypoxic microenvironment in TB lesions. From these initial data, it appears that 68 Ga-nitroimidazole is a promising candidate for monitoring hypoxic load in patients diagnosed with TB. Such imaging could identify patients who would benefit from individualised therapy targeting other mechanisms in the TB microenvironment with the intention to predict or improve treatment response.

PET/CT features of a novel gallium-68 labelled hypoxia seeking agent in patients diagnosed with tuberculosis: a proof-of-concept study.

INTRODUCTION: Positron emission tomography/computed tomography (PET/CT) in infection and inflammation has yielded promising results across a range of radiopharmaceuticals. In particular, PET/CT imaging of tuberculosis (TB) allows for a better understanding of this complex disease by providing insights into molecular processes within the TB microenvironment. TB lesions are hypoxic with research primarily focussed on cellular processes occurring under hypoxic stress. With the development of hypoxia seeking PET/CT radiopharmaceuticals, that can be labelled in-house using a germanium-68/gallium-68 (68Ge/68Ga) generator, a proof-of-concept for imaging hypoxia in TB is presented. METHODS: Ten patients diagnosed with TB underwent whole-body PET/CT imaging, 60-90 min after intravenous administration of 74-185 MBq (2-5 mCi) 68Ga-nitroimidazole. No oral or intravenous contrast was administered. Images were visually and semiquantitatively assessed for abnormal 68Ga-uptake in the lungs. RESULTS: A total of 28 lesions demonstrating hypoxic uptake were identified. Low- to moderate-uptake was seen in nodules, areas of consolidation and cavitation as well as effusions. The mean standard uptake value (SUVmean) of the lesions was 0.47 (IQR, 0.32-0.82) and SUVmax was 0.71 (IQR, 0.41-1.11). The lesion to muscle ratio (median, 1.70; IQR, 1.15-2.31) was higher than both the left ventricular and the aorta lesion to blood ratios. CONCLUSION: Moving towards the development of unique host-directed therapies (HDT), modulation of oxygen levels may improve therapeutic outcome by reprogramming TB lesions to overcome hypoxia. This proof-of-concept study suggests that hypoxia in TB lesions can be imaged and quantified using 68Ga-nitroimidazole PET/CT. Subsequently, hypoxic load can be estimated to inform personalised treatment plans of patients diagnosed with TB.

An overview of the developments and potential applications of 68Ga-labelled PET/CT hypoxia imaging.

Non-invasive imaging of hypoxia plays a role in monitoring the body's adaptive response or the development of pathology under hypoxic conditions. Various techniques to image hypoxia have been investigated with a shift towards the use of molecular imaging using PET/CT. The role of hypoxia-specific radiopharmaceuticals such as radiolabelled nitroimidazoles is well documented particularly in the oncologic setting. With the increasing utilisation of in-house labelling with a PET benchtop generator, such as the 68Ge/68Ga generator, the use of 68Ga-labelled hypoxic radiopharmaceuticals in the clinical setting is developing. Since hypoxia plays a role in various pathologic states including infectious disease such as TB, there is a need to explore the potential application of 68Ga-labelled hypoxia seeking radiopharmaceuticals beyond oncology. The purpose of this review is to describe the developments of 68Ga-labelled hypoxic radiopharmaceuticals including the various chelators that have been investigated. Further, the role of hypoxia imaging in various pathologies is discussed with particular emphasis on the potential clinical applications of hypoxia PET/CT in TB.

Association between ultrasound morphologic features and histopathological findings of lobular carcinoma.

INTRODUCTION: Despite the incidence and recurrence rates of breast cancer, there are currently no biomarkers to predict which cases will develop into lobular carcinoma (LC). The purpose of this study was to determine the association between ultrasound morphologic characteristics of LC and histopathological classifications. METHODS: A retrospective, cross-sectional study was conducted on the ultrasound images and histopathological reports of 100 patients with a confirmed LC diagnosis between January 2013 and December 2016. RESULTS: Morphologic ultrasound characteristics most frequently reported in the dataset of positively diagnosed LC patients were; irregular ultrasound shape (86%), hypoechoic echogenicity (88%), poorly circumscribed margin (95%), posterior acoustic enhancement (93%) and absent calcifications (81%). Using Fisher's extract test, it was found that stromal fibrosis, single file type pattern, atypical lobular hyperplasia and LC Grade II were significantly correlated with irregular shape and hypoechoic echogenicity. CONCLUSION: A prognostic predictor tool can be designed from this study's findings which can then be used in practice to raise awareness of the unique morphometric markers related to LC of the breast.

Twelve tips for supervisors to move towards person-centered research supervision in health care sciences.

The research supervisory role is becoming increasingly complex due to issues such as diversity of students; mismatched expectations between the student, supervisor and higher education institution and shorter and specific time-bound research outcomes. The current postgraduate research supervision culture and supervision practices should change. Moving towards person-centered research supervision practices may enhance the research environment, as healthful relationships between supervisors and postgraduate students may lead to increased postgraduate research outcomes. Using a World Café, we critically reflected on our existing research supervision practices. All healthcare educators involved in postgraduate research supervision were purposively selected to participate. During the café, we explored and shared ideas in a safe space. Twelve tips emerged, which can be implemented to move existing supervision practices towards person-centered research supervision practices. We present these twelve tips from the perspective of the four constructs of person-centeredness as outlined by McCormack and McCance - pre-requisites, environment, process, and outcomes. The use of these tips may enable both supervisors and students to flourish. Avoiding routine, ritual supervision practices and embracing person-centredness, will enable supervisors to form healthful relationships and put the postgraduate student at the heart of our supervision practices.

A randomized-controlled study of a modified technique to reduce extracardiac activity in myocardial perfusion imaging.

INTRODUCTION: Various techniques have been used in an attempt to reduce interfering extracardiac activity in myocardial perfusion imaging with inconsistent results. The aim of this study was to investigate the effect of a combined intervention on the frequency and intensity of interfering extracardiac activity. METHODS: Patients (n=230) routinely referred for a 2-day stress-rest myocardial perfusion examination were assigned randomly to one of two groups. Group A (n=114) received a single intervention (diluted lemon juice) before stress imaging and a combined intervention (diluted lemon juice and soda water) before rest imaging. Interventions were reversed for group B (n=116). Three interpreters, blinded to the intervention, assessed early and delayed planar images from 195 patients in terms of the frequency and the intensity of interfering extracardiac activity. RESULTS: The myocardial to extracardiac (MYO : EXC) ratio between groups for the rest studies was marginally not significant (P=0.060 and 0.059), showing an increase in ratio when the combined intervention was administered. There were significant differences (P≤0.001) in the frequency, intensity, and MYO : EXC ratio between the early and the delayed studies. CONCLUSION: Combining interventions that stimulate radiopharmaceutical hepatic excretion and utilize the volume effect is advantageous in myocardial perfusion imaging, with delayed imaging being advocated as a complementary intervention.

A study of technetium-99m wastage in selected private sector nuclear medicine imaging departments.

BACKGROUND: South African nuclear medicine imaging departments have been fortunate in being able to receive an uninterrupted supply of molybdenum-99 (99Mo)/technetium-99m (99mTc) generators. Nuclear medicine radiographers practising in private sector services in the northern Gauteng region indicated a possible problem with the quantities of wasted and unused 99mTc radiopharmaceuticals returned to the radiopharmaceutical supply laboratory. Daily radiopharmaceutical deliveries are a combination of ordered packages and standard packages. The purpose of the standard package is to accommodate emergency and after-hours nuclear medicine services. The purpose of the study was to interrogate the unconfirmed reports of 99mTc radiopharmaceutical wastage. METHODS: A descriptive quantitative research design was conducted in six private sector nuclear medicine imaging practices in the northern Gauteng region. Overt observations of the quantities of radiopharmaceutical supply, usage and wastage were conducted over 2 days in each of these practices. RESULTS: Ordered packages comprised 14% of the total 99mTc radiopharmaceutical deliveries to these six nuclear medicine imaging departments. It was identified that:(1) a total of 83.2% of ordered packages and 35.1% of standard packages of preprepared syringes were utilized;(2) a total of 36% of ordered packages and 22.6% of standard packages of bulk 99mTc were utilized; and (3) a total of 70.6% of the total quantity of radiopharmaceuticals was returned to the radiopharmaceutical laboratory. The total wastage represented 45.5% of the ordered packages and 75.8% of the standard packages. CONCLUSION: Wastage of 74 GBq of 99mTc from six sites over 12 days should raise concerns for the nuclear medicine industry. A review of the system framework that supports communication between the radiopharmaceutical supplier/s and the nuclear medicine imaging practices is recommended.