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A 62-year-old man with prostate cancer underwent both F-PSMA-1007 and F-fluorocholine PET/CT studies for biochemical recurrence. F-PSMA-1007 PET/CT outperformed F-fluorocholine PET/CT in detecting lymph node metastases in the pelvis and retroperitoneum, whereas the former showed a focus of increased uptake in the spleen not seen on F-fluorocholine. The F-PSMA-1007 -avid lesion corresponded to a splenic hemangioma, which was initially detected in an MRI scan 10 years ago, unchanged in size. This case shows different features of F-PSMA-1007 and F-fluorocholine uptake, in an incidentally detected splenic hemangioma, alerting PET/CT reports for possible pitfall.

Prostate-specific membrane antigen (PSMA) is a membrane glycoprotein that is overexpressed in prostate cancer cells. It is also expressed in other normal tissues and several other malignant and benign diseases. We present a case of a 69-year-old man with history of prostate adenocarcinoma who underwent F-PSMA-1007 PET/CT due to suspected biochemical recurrence. PET/CT showed F-PSMA-1007 uptake in healing rib fractures with no other pathologic findings. Clinicians reporting F-PSMA-1007 PET/CT should be aware of this potential pitfall, especially in nontypical trauma pattern (eg, solitary osseous lesion) mimicking bone metastases.

OBJECTIVE. The purposes of this article are to review the common biologic features of cancer and coronary artery disease assessed with PET tracers, focusing on those already used in the clinic and those with translational potential, and to discuss the current value and expected contribution of PET in diagnosis, risk stratification, and treatment monitoring. CONCLUSION. PET using a wide variety of radiotracers enhances understanding of pathophysiologic changes shared by cancer and coronary artery disease, helps establish an accurate diagnosis, and aids in prognostic assessment and management decisions. It is likely that with the evolution of therapeutic strategies for blocking the development and progression of both diseases and with the introduction of novel, specific ligands in clinical practice, PET will play an ever stronger role in diagnosis, risk stratification, and monitoring of therapy.

Renal DMSA uptake provides an index for evaluation of the functional tubular mass, which depends on the renal blood flow, proximal tubular cell membrane function, and urinary acid-base balance. We present a case of a nonazotemic 48-year-old adult with β-thalassemia major under regular blood transfusions and iron chelation therapy that underwent DMSA scan showing minor cortical abnormalities and high background activity, featuring prominent cardiac blood pool and liver uptake. This case highlights the pitfall of high background activity during DMSA study in patients with β-thalassemia major due to tubular disorders.

The present study investigated differences and associations between cortical perfusion, nigrostriatal dopamine pathway and neuropsychological functions in different stages of Parkinson’s disease (PD). We recruited 53 non-demented PD patients divided into four groups according to the Hoehn and Yahr (HY) staging system and 20 healthy controls who were used in the comparison of the neuropsychological findings. Each patient underwent two separate brain single photon emission computed tomography (SPECT) studies (perfusion and dopamine transporter binding) as well as neuropsychological evaluation. Perfusion images of each patient were quantified and compared with a normative database provided by the NeuroGam software manufacturers. Mean values obtained from the cortical areas and neuropsychological measures in the different groups were also compared by analysis of covariance (ANCOVA) controlling for disease duration and educational level. We found cognitive deficits especially in the late PD stages (HY 3, 4 and 5) compared to the early stages (HY 1 and 2) and associations between cognitive decrements and cortical perfusion deterioration mainly in the frontal and posterior cortical areas. Compared with controls, PD patients showed impairments of cognition and cerebral perfusion that increased with clinical severity. Furthermore, we found a significant correlation between the performance on the phonemic fluency task and regional cerebral blood flow (rCBF) in the left frontal lobe. Dopamine transporter binding in the left caudate nucleus significantly correlated with blood flow in the left dorsolateral prefrontal cortex (DLPFC), but not with measures of executive functions. There are significant cognitive and perfusion deficits associated with PD progression, implying a multifactorial neurodegeneration process apart from dopamine depletion in the substantia nigra pars compacta (SNc).

In the present study, we examined relationships between neuropsychological functions and brain single photon emission computed tomography (SPECT) regional cerebral blood flow (rCBF) observed at presurgical evaluation for deep brain stimulation (DBS) of the subthalamic nucleus (STN) in advanced Parkinson’s disease (PD) patients. Twenty advanced non-demented PD patients, candidates for DBS surgery, underwent perfusion brain SPECT study and neuropsychological assessment prior to surgery (range: 30–50 days). Patients were further assessed using the Unified Parkinson’s Disease Rating Scale (UPDRS) and Hoehn and Yahr (H&Y) scale. During all assessments patients were “on” standard medication. NeuroGam software, which permits voxel by voxel analysis, was used to compare the brain perfusion of PD patients with a normal database adjusted for sex and age. Neuropsychological scores were compared to age, education and sex-adjusted normative databases. Our results indicated that the distribution of rCBF showed significant differences when compared to an age- and sex-adjusted normative database. We found impaired blood flow in 17 (85%) of our patients in the left prefrontal lobe, in 14 (70%) in the right prefrontal lobe and in 11 (55%) in the left frontal and right parietal lobes. Neuropsychological testing revealed that 18 (90%) of our patients had significant impairments in measures of executive functions (set-shifting) and 15 (75%) in response inhibition. Furthermore, we found significant correlations between measures of visual attention, executive functions and the right frontal lobe region. The presence of widespread blood flow reduction was observed mainly in the frontal lobes of dementia-free patients with advanced PD. Furthermore, performance on specific cognitive measures was highly related to perfusion brain SPECT findings.

Background – Tardive dyskinesia (TD) is a neurological disorder typically induced by long-term exposure to neuroleptics. Deep brain stimulation (DBS) of the globus pallidus internus (GPi) may represent a therapeutic alternative for TD, which is often resistant to conservative treatment. Aims of the study – This report’s objective is to present a case of TD successfully treated with DBS, as well as to indicate a putative role of brain perfusion scintigraphy as a helpful tool correlating functional imaging findings with clinical responsiveness to DBS. Methods/Results – A 42-year-old male patient suffering from refractory TD underwent bilateral GPi DBS surgery. Post-operative Burke-Fahn-Mardsen Dystonia Rating Scale (BFMDRS) and Abnormal Involuntary Movement Scale (AIMS) total scores have been reduced by 90.7% and 76.7% respectively on the 6-month follow-up assessment. Brain perfusion scintigraphy, performed post-operatively in the two stimulation states, revealed a decrease in cerebral blood flow, during the ‘on-DBS’, compared with the ‘off-DBS’ state. Conclusions – Clinical improvement of this patient, correspondent to previous studies, suggests that continuous bilateral GPi DBS may provide a promising treatment option for TD. Furthermore, this report could imply, as no previous such comparison study exists, a possible correlation between brain functional imaging findings and the movement disorder’s response to DBS.

Incidental thyroid FDG uptake is not rarely encountered on PET studies. In this case, we present an incidental thyroid focus of F-FDG uptake identified in a patient with splenic marginal zone lymphoma during the baseline and the response assessment PET/CT study that proved to be medullary thyroid carcinoma on subsequent histological examination.

A case of idiopathic basal ganglia calcification in a 56-year-old woman with parkinsonism and cognitive impairment is described. The nigrostriatal dopaminergic pathway and regional cerebral blood flow were evaluated using dopamine transporter (DAT) brain single photon emission tomography combined with a low-dose x-ray computerized tomography transmission (hybrid SPECT/CT) and Tc-99m HMPAO brain perfusion SPECT study, respectively. DAT SPECT/CT imaging revealed a reduction in DAT binding in both striatum regions coinciding with bilateral calcifications in the basal ganglia. Brain perfusion scan showed hypoperfusion in basal ganglia regions, posterior parietal cortex bilaterally, left frontopolar and dorsolateral prefrontal cortex, and left temporal lobe. These findings correlated well with the clinical condition of the patient. Mineralization may play a critical role in the pathogenesis of neuronal degeneration. Cortical perfusion changes in patients may better explain the patient's altered cognitive and motor functions.

To investigate the potential role of Tc-99m depreotide (Tc-DEPR) in the preoperative lymph node (N) staging of non-small-cell lung cancer (NSCLC).Sixty-one patients with NSCLC at the potentially operable stage were enrolled and underwent scintigraphy before surgery (n=56) or mediastinoscopy (n=5). Imaging was performed with a hybrid single photon emission computed tomography/computed tomography (SPECT/CT) system. Depreotide uptake in N stations was evaluated visually and semi-quantitatively and compared to histology. Quantification was carried out in attenuation-corrected SPECT slices. Different sites of normal uptake were used as a reference for comparison with lesional uptake. Receiver operating characteristic analysis was employed to identify the most preferable reference area and the cut-off best discriminating disease-free from disease-involved lymph nodes.With reference to 53 Ν1 hilar and 147 Ν2/Ν3 sampled stations, sensitivity of scintigraphy by visual interpretation was 100 and 94%, specificity 43 and 59% and accuracy 55 and 67%, respectively. No patient was down-staged, but 52% were incorrectly up-staged and 44% were misclassified as inoperable. Compared to scintigraphy, preoperative contrast-enhanced diagnostic CT demonstrated lower sensitivity (36% for hilar and 73% for N2/N3 stations), higher specificity (79 and 75%) and similar accuracy (70 and 75%). Regarding the ultimate N-stage and the prediction of surgical disease, diagnostic CT was wrong in 51 and 34% of cases. Dichotomy of quantitative scintigraphic data by the use of certain N-to-spine ratio cut-offs resulted in a significant increase of specificity (76% for hilar and 89% for N2/N3 stations), while sensitivity remained high (82% in both circumstances) and accuracy for Ν2/Ν3 stations was substantially improved (88%). By this quantitative approach, misclassifications as to the N-stage and patient operability (25 and 16%) were considerably less than that of visual Tc-DEPR and diagnostic CT interpretations.Tc-99m depreotide SPECT/CT seems to have a role in the N-staging of NSCLC, mainly because of its high sensitivity and negative predictive value. Quantification of uptake can improve specificity, at a low cost of sensitivity. If F-18 fluoro-deoxyglucose positron emission tomography is not available, this method may be used as a surrogate to conventional staging modalities.

Background Meige's syndrome is a rare form of segmental dystonia characterized by blepharospasm and oromandibular dystonia. Medical treatment including botulinum toxin injections usually present disappointing results. The experience on Deep Brain Stimulation (DBS) in the treatment of Meige's syndrome and other segmental dystonias is still limited. At the moment, only a few cases of pallidal DBS have been reported to improve this rare form of dystonia. Case description We report on a case of a woman with a 7-year history of Meige's syndrome, which rendered her functionally blind. The treatment with botulinum toxin injections failed to improve her symptoms, whereas stereotactic bilateral DBS of the pallidum led to a dramatic clinical improvement. Clinical assessment using the Burke–Fahn–Mardsen Dystonia Rating Scale (BFMDRS) in a double-blind manner, showed an improvement of 70% in the Movement score and 93.33% in the Disability score (84% reduction of the total score) on the 3 and 6 month follow-up. Conclusions Stereotactic pallidal DBS might be considered as a potential treatment in the management of Meige's syndrome.