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Background: Neuropsychiatric systemic lupus erythematosus (NPSLE) is a major contributor to morbidity and mortality in systemic lupus erythematosus (SLE) patients. To date no single clinical, laboratory or imaging test has proven accurate for NPSLE diagnosis which is a testament to the intricate and multifactorial pathophysiological mechanisms suspected to exist. Functional imaging with FDG PET-CT has shown promise in NPSLE diagnosis, detecting abnormalities prior to changes evident on anatomical imaging. Research indicates that NPSLE may be more aggressive in people of African descent with higher mortality rates, making rapid and correct diagnosis even more important in the African context. Methods: In this narrative review, we provide a thorough appraisal of the current literature on the role of FDG PET-CT in NPSLE. Large, well-known databases were searched using appropriate search terms. Manual searches of references of retrieved literature were also included. Findings: A total of 73 article abstracts were assessed, yielding 26 papers that were directly relevant to the topic of FDG PET-CT in NPSLE. Results suggest that FDG PET-CT is a sensitive imaging test for NPSLE diagnosis and may play a role in assessing treatment response. It is complementary to routine anatomical imaging, particularly in diffuse manifestations of the disease. Newer quantitative analyses are commonly used for interpretation and can detect even subtle abnormalities, missed on visual inspection. Findings of group-wise analyses of FDG PET-CT scans in NPSLE patients are important in furthering our understanding of the complicated pathophysiological mechanisms involved. Limitations of FDG PET-CT include its lack of specificity, high cost and poor access. Conclusion: FDG PET-CT is a sensitive test for NPSLE diagnosis but is hampered by lack of specificity. It is a valuable tool for clinicians managing SLE patients, particularly when anatomical imaging is negative. Its exact application will depend on the local context and clinical scenario.

Abstract Purpose Ventilation–perfusion single-photon emission computed tomography (VP SPECT) plays an important role in pulmonary embolism diagnosis. Rapid results may be obtained using same-day ventilation followed by perfusion imaging, but generally requires careful attention to achieving an optimal count rate ratio (P/V ratio) of ≥ 3:1. This study investigated whether the ratio of counts simultaneously acquired in adjacent primary and Compton scatter energy windows (E ratio) on V SPECT was predictive of final normalised perfusion count rate (PCRnorm) on P SPECT using [99mTc]Tc-macroaggregated albumin (MAA), thus allowing for optimisation of P/V ratios. Methods Same-day VP SPECT studies acquired using standard protocols in adult patients during a 2-year period (training dataset) were assessed. Studies were included provided they were acquired with correct imaging parameters, and injection site imaging and laboratory records were available for quality control and normalised count rate corrections. Extraction of DICOM information, and linear regression were performed using custom Python and R scripts. A predictive tool was developed in Microsoft Excel. This tool was then validated using a second (validation) dataset of same-day studies acquired over a subsequent 7-month period. Accuracy of the prediction tool was assessed by calculating the mean absolute percentage error (MAPE). Results Of 643 studies performed, the scans of 342 participants (median age 30.4 years, 318 female) were included in the training dataset, the analysis of which yielded a significant regression equation (F(1,340) = 1057.3, p

Introduction A considerable burden of the tuberculosis (TB) epidemic is found in adolescents. The reasons for increased susceptibility to TB infection and higher incidence of TB disease in adolescence, compared with the 5–10 years old age group, are incompletely understood. Despite the pressing clinical and public health need to better understand and address adolescent TB, research in this field remains limited.Methods and analysis Teen TB is an ongoing prospective observational cohort study that aims to better understand the biology, morbidity and social context of adolescent TB. The study plans to recruit 50 adolescents (10–19 years old) with newly diagnosed microbiologically confirmed pulmonary TB disease and 50 TB-exposed controls without evidence of TB disease in Cape Town, South Africa, which is highly endemic for TB. At baseline, cases and controls will undergo a detailed clinical evaluation, chest imaging, respiratory function assessments and blood collection for viral coinfections, inflammatory cytokines and pubertal hormone testing. At 2 weeks, 2 months and 12 months, TB disease cases will undergo further chest imaging and additional lung function testing to explore the patterns of respiratory abnormalities. At week 2, cases will complete a multicomponent quantitative questionnaire about psychological and social impacts on their experiences and longitudinal, in-depth qualitative data will be collected from a nested subsample of 20 cases and their families.Ethics and dissemination The study protocol has received ethical approval from the Stellenbosch University Health Research Ethics Committee (N19/10/148). The study findings will be disseminated through peer-reviewed publications, academic conferences and formal presentations to health professionals. Results will also be made available to participants and caregivers.

Abstract Background There is a growing interest in the use of F-18 FDG PET-CT to monitor tuberculosis (TB) treatment response. Tuberculosis lung lesions are often complex and diffuse, with dynamic changes during treatment and persisting metabolic activity after apparent clinical cure. This poses a challenge in quantifying scan-based markers of burden of disease and disease activity. We used semi-automated, whole lung quantification of lung lesions to analyse serial FDG PET-CT scans from the Catalysis TB Treatment Response Cohort to identify characteristics that best correlated with clinical and microbiological outcomes. Results Quantified scan metrics were already associated with clinical outcomes at diagnosis and 1 month after treatment, with further improved accuracy to differentiate clinical outcomes after standard treatment duration (month 6). A high cavity volume showed the strongest association with a risk of treatment failure (AUC 0.81 to predict failure at diagnosis), while a suboptimal reduction of the total glycolytic activity in lung lesions during treatment had the strongest association with recurrent disease (AUC 0.8 to predict pooled unfavourable outcomes). During the first year after TB treatment lesion burden reduced; but for many patients, there were continued dynamic changes of individual lesions. Conclusions Quantification of FDG PET-CT images better characterised TB treatment outcomes than qualitative scan patterns and robustly measured the burden of disease. In future, validated metrics may be used to stratify patients and help evaluate the effectiveness of TB treatment modalities.

Positron emission tomography combined with X-ray computed tomography (PET-CT) has an established role in the management of brain disorders, but may be underutilised in South Africa. Possible barriers to access include the limited number of PET-CT facilities and the lack of contemporary guidelines for the use of brain PET-CT in South Africa. The current review aims to highlight the evidence-based usage of brain Positron emission tomography (PET) in dementia, movement disorders, brain tumours, epilepsy, neuropsychiatric lupus, immune-mediated encephalitides, and brain infections. While being areas of research, there is currently no clinical role for the use of PET-CT in traumatic brain injury or in psychiatric or neurodevelopmental disorders. Strategies to expand the appropriate use of PET-CT in brain disorders are discussed in this article.

Background: Staging for breast cancer patients, as defined by the American Joint Committee on Cancer (AJCC), has historically been limited to anatomical staging. However, the eighth version of the AJCC guidelines has been altered to include tumour biology. Anatomical staging still has a place especially in low-middle income countries where the majority of patients present with locally advanced or metastatic disease. Aim: This review article considers which newly diagnosed breast cancer patients should be referred for anatomical staging and the pros and cons of the different modalities available in South Africa. Method: The different modalities available were reviewed with respect to metastatic screening for asymptomatic women. The usefulness of the modalities were considered with reference to organ-specific disease rather than the stage of the patient. Results: Any person with newly diagnosed breast cancer and symptoms suggestive of systemic involvement should be investigated. All symptomatic women who present with a tumour larger than 5 cm, radiological or clinical evidence of nodal disease, triple negative or HER2+ve tumours should have metastatic screening. This gives information about the primary as well as the metastatic status. Conclusion: However, increasingly, the major determinant of treatment is the biology of the cancer and not the anatomical stage. In future, this trend is likely to increase with anatomical staging becoming less important.

Musculoskeletal TB occurs in 3% of patients with TB, while chest wall TB constitutes 5% of all cases of musculoskeletal TB.2 Tuberculous abscesses of the chest wall are uncommon but are seen in endemic areas. Imaging modalities such as X-ray, computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography in combination with CT (PET-CT) using fluorine-18 fluorodeoxyglucose (FDG) improve diagnostic performance, especially in diagnosing complications of TB. Children constitute up to a fifth of the tuberculosis (TB) caseload in high-incidence countries and account for 8-20% of TB-related deaths.1 Challenges in the diagnosis of TB result in a delay in starting TB drugs and poor outcomes. [Extracted from the article]

The estimation of predicted postoperative (PPO) lung function is important in lung resection candidates. We utilized simple anatomical calculations and single-photon emission computed tomography combined with computed tomography (SPECT-CT) to calculate PPO in 24 consecutive patients with impaired pulmonary function who underwent lung resection. PPO values calculated by anatomical calculations and three-dimensional lobar SPECT-CT quantification both correlated well with the postoperative forced expiratory volume in 1 s, with r = 0.825, p < 0.001 and r = 0.796, p < 0.001, respectively. Both techniques fared well at predicting postoperative lung function, but our observations unexpectedly suggested that simple anatomical calculations might be equivalent to three-dimensional SPECT-CT lobar quantification. [ABSTRACT FROM AUTHOR]

A case of a 50-year-old woman who was referred for the evaluation of possible ACTH-dependent Cushing’s syndrome (CS) is described. The localisation of ACTH-dependent CS remains difficult despite many advances in diagnostic approaches. No single test can accurately determine the location of ACTH excess and therefore a combination of non-invasive imaging, stimulation and suppression tests are advised. The recent advances, current utility and pitfalls of each of these tests are reviewed. If non-invasive tests fail to confidently localise the source of ACTH excess, inferior petrosal sinus sampling (IPSS) should follow. Recent advances improving the diagnostic accuracy of IPSS, such as DDAVP stimulation and simultaneous sampling for prolactin is discussed. Where ectopic ACTH production is suspected, newer nuclear medicine techniques, such as somatostatin receptor imaging that recently became available in South Africa, can be utilised. The role of nuclear medicine imaging in identifying ectopic ACTH production is discussed briefly. [ABSTRACT FROM AUTHOR]

Introduction Reconstruction influences the quantitative results in PET imaging. The aim of this study was the evaluation of different image reconstruction parameters and their impact on quantification for 18 F-FDG PET of the brain. The reconstruction parameters studied were the number of iterations, smoothing levels (relaxation parameter lambda), and the use of time of flight (TOF) information. In addition, we investigated the effect of signal-to-noise ratio on each of these reconstructed brain images, as well as the effect of scan duration on image quality. Materials and Methods A Philips® Gemini-TF Big bore PET/CT was used for acquiring data of a 3D Hoffman Brain phantom. Data was acquired for 25 minutes in list mode format after injection of 40 MBq FDG, and reconstructed with a voxel size of 2 × 2 × 2 mm 3 using two different iterative reconstruction algorithms: LOR-RAMLA and BLOB-OS. The number of iterations and subsets was varied successive from 3/33 (vendor default) to 30/33, acquisition scan duration from 1 to 25 minutes, lambda was selected as smooth (0.7) and normal (1.0), and TOF was switched on and off for BLOB-OS. The impact on image quality was analyzed in 15 cortical and subcortical brain regions (volumes of interest, VOIs) and for grey and white matter. Results Contrast increased for all regions of the brain and for grey matter/white matter (GM/WM) ratio if the number of iterations increased. Image convergence was reached after fifteen iterations for all different algorithms. When varying the smoothing filter it was found that lambda 1.0 resulted in a faster convergence than 0.7. The coefficient of variation (COV) for all VOIs showed BLOB-OS with TOF to be superior to the other algorithms. The COV results for different scan durations showed only a minimal improvement after 5 minutes in high-activity regions (GM), and after 10 minutes in low-activity regions (WM). Conclusion Based on phantom data 18 F-FDG brain imaging for 10 minutes and reconstructed with the BLOB-OS algorithm including TOF information with 15 iterations is optimal on the Philips Gemini TF Big bore PET/CT. Further analyses is planned using patient data to verify if these findings remain valid in a clinical setting. [ABSTRACT FROM AUTHOR]

Background: Staging for breast cancer patients, as defined by the American Joint Committee on Cancer (AJCC), has historically been limited to anatomical staging. However, the eighth version of the AJCC guidelines has been altered to include tumour biology. Anatomical staging still has a place especially in low-middle income countries where the majority of patients present with locally advanced or metastatic disease. Aim: This review article considers which newly diagnosed breast cancer patients should be referred for anatomical staging and the pros and cons of the different modalities available in South Africa. Method: The different modalities available were reviewed with respect to metastatic screening for asymptomatic women. The usefulness of the modalities were considered with reference to organ-specific disease rather than the stage of the patient. Results: Any person with newly diagnosed breast cancer and symptoms suggestive of systemic involvement should be investigated. All symptomatic women who present with a tumour larger than 5 cm, radiological or clinical evidence of nodal disease, triple negative or HER2+ve tumours should have metastatic screening. This gives information about the primary as well as the metastatic status. Conclusion: However, increasingly, the major determinant of treatment is the biology of the cancer and not the anatomical stage. In future, this trend is likely to increase with anatomical staging becoming less important. [ABSTRACT FROM AUTHOR]