Stress-first single photon emission computed myocardial perfusion imaging

Background. Myocardial perfusion imaging (MPI) with single photon emission tomography (SPET) is widely used in coronary artery disease evaluation. Recently major dosimetric concerns have arisen. The aim of this study was to evaluate if a pre-test scoring system could predict the results of stress SPET MPI, thus avoiding two radionuclide injections. Methods. All consecutive patients (n=309) undergoing SPET MPI during the first 6 months of 2014 constituted the study group. The scoring system is based on these characteristics: age >65 years (1 point), diabetes (2 points), typical chest pain (2 points), congestive heart failure (3 points), abnormal ECG (4 points), male gender (4 points), and documented previous CAD (5 points). The patients were divided on the basis of the prediction score into 3 classes of risk for an abnormal stress-first protocol. Results. An abnormal stress SPET MPI was present in 7/31 patients (23%) with a low risk score, in 24/90 (27%) with an intermediate score risk, and in 124/188 (66%) with an high score risk. ROC curve analysis showed good prediction of abnormal stress MPI. Conclusions. Our results suggest an appropriate use of a pre-test clinical prediction formula of abnormal stress MPI in a routine clinical setting

Progressive Supranuclear Palsy-Like Phenotype in a GBA E326K Mutation Carrier

Mutations in the beta‐glucocerebrosidase gene (GBA ), encoding the lysosomal enzyme that is deficient in Gaucher's disease (GD), are important and common risk factors for Parkinson's disease (PD) and Lewy body dementia (LBD; i.e., α‐synucleinopathies). PD patients with GBA mutations have younger age at onset and are more likely to develop cognitive dysfunction. There are approximately 300 known GBA mutations and determining accurate exact genotype‐phenotype correlations is challenging. In general, GBA mutations were found to variably influence PD risk according to their impact on the protein function. The GBA variant, E326K, has long been considered a polymorphism, given that homozygous individuals do not develop GD. However, this variant was found to reduce GBA enzymatic activity in vitro and mildly increase the risk to develop PD (OR:1.7), with frequent development of associated dementia. The impact of GBA mutations on the risk to develop tauopathies is less defined, given that previous studies failed to report a significant association with PSP and corticobasal degeneration. Yet, more recent data suggest that the clinical phenotype of GBA‐associated neurodegeneration is more heterogeneous than previously assumed, including phenotypes distinct from α‐synucleinopathies. Herein, we report on a patient with an unusual phenotype characterized by supranuclear vertical gaze palsy at onset with late emergence of postural instability carrier of the GBA E326K variant

Assessment of therapy response to Regorafenib by 18F-DOPA-PET/CT in patients with recurrent high-grade gliomas: a case series

Purpose: Regorafenib (REG) has been recently approved for the treatment of relapsed glioblastoma. Contrast-enhanced (CE) magnetic resonance (MR) imaging represents the gold standard for diagnosis and surveillance of brain tumors. We evaluated the potential role of 18F-DOPA PET/CT in determining the response to REG in a case series of patients with recurrence of high-grade gliomas. Methods: Three patients with recurrence of high-grade gliomas underwent CE-MR and 18F-DOPA PET/CT within 1 week before and at 8-week intervals after REG therapy. 18F-DOPA PET was analyzed using qualitative and quantitative approaches. For the quantitative analysis, maximum (SUVmax), mean standardized uptake values (SUVmean) and metabolic tumor volume (MTV) were obtained. Results: In two patients, an early metabolic response to REG treatment, both visually and in terms of reduction of SUVmax, SUVmean and MTV, was observed. In one subject, no metabolic response was detected. Metabolic PET data were in agreement with morphological and perfusion MRI data in two patients. In one patient, while 18F-DOPA was able to correctly diagnose a metabolic response to REG, MRI had misdiagnosed a pseudo-progression of the disease. Discussion: These preliminary findings suggest that 18F-DOPA PET/CT allows an early and reliable assessment of metabolic response to the REG treatment. A major advantage of PET seems to be obtained in patients in whom MR is unable to differentiate non-response vs tumor pseudo-progression