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Background: Molecular imaging using positron emission tomography/computerized tomography (PET/CT) may add relevant incremental diagnostic information to standard structural cross-sectional imaging. Such information may allow identification of patients with rectal cancer that are more likely to develop complete tumor regression after neoadjuvant chemoradiation therapy (CRT). The objective of this report was to identify PET/CT features that are associated with a complete response after CRT. Methods: 99 cT2-4N0-2M0 distal rectal cancer patients (≤7 cm from anal verge) were included in this prospective single center trial (NCT 00254683). Patients underwent baseline PET/CT followed by 54 Gy and 5-fluorouracil-based neoadjuvant CRT. After completion of therapy, patients underwent 6- and 12-week PET/CT. Clinical assessment of tumor response was performed at 12 weeks and was blinded to radiological information. Patients were treated according to clinical assessment. Results: There were seven patients with a complete pathological response (pCR) and 16 with a complete clinical response (cCR) (23 complete responders). Comparison of pCR exclusively and non-pCR revealed that only baseline primary tumor standard uptake value (SUV) was a significant predictor of response. Comparison of complete responders (pCR or cCR) and non-complete responders showed that depth of rectal wall uptake at baseline PET/CT ( p = 0.002) and variation between baseline and 12-week maximum standard uptake value (SUVmax) of primary tumor ( p = 0.001) were independent predictors for complete response at multivariate analysis. A decrease >67 % between baseline and 6-week or 76 % between baseline and 12-week SUVmax were associated with complete response (pCR or cCR; p = 0.02 and p < 0.001, respectively). Conclusions: Positron emission tomography/computerized tomography at baseline, 6 and 12 weeks, may provide information regarding patients with a higher likelihood of developing complete tumor regression following neoadjuvant CRT. [ABSTRACT FROM AUTHOR]

Purpose: The precise determination of organ mass ( mth) and total number of disintegrations within the thyroid gland ( [ABSTRACT FROM AUTHOR]

Objectives To evaluate the cognitive performance of a group of patients with Wilson's disease ( WD) and to correlate the cognitive findings with changes in magnetic resonance imaging ( MRI). Methods All patients with WD consecutively attended in a Movement Disorders Clinic between September 2006 and October 2007 were invited to participate in the study, together with a group of matched healthy controls. Patients and controls were submitted to comprehensive neuropsychological assessment. MRI was performed in all patients, and abnormalities (high-intensity signal, low-intensity signal and atrophy) were semi-quantitatively rated. Performance of patients and controls in each cognitive test was compared, and correlations between cognitive scores and MRI changes were investigated within the patients' group. Results Twenty patients with WD (11 men) and 20 controls (nine men) were evaluated. Mean age in the WD and control groups was 30.05 ± 7.25 and 32.15 ± 5.37 years, respectively. Mean schooling years were 11.15 ± 3.73 among WD cases and 10.08 ± 2.62 among controls. Patients with WD performed significantly worse than controls in the Mini-Mental State Examination, Dementia Rating Scale, phonemic verbal fluency ( FAS), verb generation, digit span forward, Stroop test, Frontal Assessment Battery and in the Brief Cognitive Screening Battery. A significant correlation emerged between global cognitive impairment and MRI scale ( r = 0.535), being higher for high-intensity signal plus atrophy ( r = 0.718). Conclusion Patients with WD presented cognitive impairment, especially in executive functions, with good correlation between cognitive abnormalities and MRI changes. [ABSTRACT FROM AUTHOR]

Aim Inguinal nodes may be a possible route for lymphatic spread in patients with distal rectal cancer. The outcome was examined for patients with distal rectal cancer undergoing neoadjuvant chemoradiation ( CRT) and having 2-fluorine-18-fluoro-2-deoxy- d-glucose ( FDG)-avid inguinal nodes using positron emission tomography/computed tomography ( PET/ CT) imaging. Method Ninety-nine consecutive patients with cT2-4N0-2M0 distal rectal adenocarcinoma were enrolled in a clinical trial ( NCT00254683) and underwent baseline PET/ CT followed by 54 Gy and 5-fluorouracil-based CRT. After CRT, patients underwent 6- and 12-week PET/ CT. Patients with positive inguinal node uptake were compared with patients with negative uptake. The inguinal region was not included in the field of radiation therapy. Results Seventeen (17%) patients had baseline positive inguinal node FDG uptake. They were more likely to have the tumour closer to the anal verge (2.0 vs 4.2 cm; P = 0.001). Of these, eight (47%) demonstrated a positive inguinal uptake at PET/ CT after 12 weeks from CRT. Patients with inguinal node FDG uptake after CRT (positive PET at baseline and 12 weeks) had a significantly worse 3-year overall and disease-free survival ( P = 0.02 and P = 0.03). After a median follow-up period of 22 months, none of these patients had developed inguinal recurrence. Conclusion Uptake of inguinal nodes at PET/ CT may be present in up to 17% of patients with distal rectal cancer, particularly with ultra-low tumours. Nearly half of these nodes no longer show uptake after CRT despite the groin area not being included in the radiation field. Persistence of inguinal node uptake 12 weeks after CRT completion may be a marker for worse oncological outcome. [ABSTRACT FROM AUTHOR]

Background and purpose: Tinnitus is a frequent disorder which is very difficult to treat and there is compelling evidence that tinnitus is associated with functional alterations in the central nervous system. Targeted modulation of tinnitus-related cortical activity has been proposed as a promising new treatment approach. We aimed to investigate both immediate and long-term effects of low frequency (1 Hz) repetitive transcranial magnetic stimulation (rTMS) in patients with tinnitus and normal hearing. Methods: Using a parallel design, 20 patients were randomized to receive either active or placebo stimulation over the left temporoparietal cortex for five consecutive days. Treatment results were assessed by using the Tinnitus Handicap Inventory. Ethyl cysteinate dimmer-single photon emission computed tomography (SPECT) imaging was performed before and 14 days after rTMS. Results: After active rTMS there was significant improvement of the tinnitus score as compared to sham rTMS for up to 6 months after stimulation. SPECT measurements demonstrated a reduction of metabolic activity in the inferior left temporal lobe after active rTMS. Conclusion: These results support the potential of rTMS as a new therapeutic tool for the treatment of chronic tinnitus, by demonstrating a significant reduction of tinnitus complaints over a period of at least 6 months and significant reduction of neural activity in the inferior temporal cortex, despite the stimulation applied on the superior temporal cortex. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article on Clostridium difficile published in the previous issue.

Objective: To evaluate the patterns of regional cerebral blood flow (rCBF) in cortical and subcortical regions by Brain SPECT imaging, in children and adolescents with obsessive-compulsive disorder (OCD) before and after treatment. Method: Fourteen OCD patients (6 to 17 years old) underwent brain SPECT; ten of those subjects were reexamined after successful treatment. rCBF ratios were correlated with clinical parameters on the 14 patients in symptomatic state, and we compared rCBF ratios of the ten patients before and after treatment. Results: There was no statistically significant difference in average ratios of rCBF before and after treatment. There were significant clinical correlations between current age and age of onset of OCD and rCBF in the bilateral superior frontal, and bilateral parietal cortical regions. Conclusions: Further investigations on abnormal neurodevelopment of cortical-subcortical circuits possibly involved in symptomatology of paediatric OCD are warranted. [ABSTRACT FROM AUTHOR]

The tools currently used to evaluate the extent of paracoccidioidomycosis (PCM) may be of limited value in detecting subclinical lesions. The aim of this study was to verify the role of gallium-67 whole-body scan in evaluating the extent of disease of 65 patients with active PCM. The [SUP67]Ga scan findings were compared with the results of clinical evaluation, chest radiography and/or high-resolution computed tomography (CT), abdominal ultrasound (US) or CT, laryngoscopy, CT or magnetic resonance imaging (MRI) of the head, and technetium-99m methylene diphosphonate bone scan, obtained before treatment. Clinically unsuspected lesions were detected by imaging procedures in 21 patients (32%), mainly in the lungs (n=11), adrenals (n=6), and superficial (n=3) and deep lymph nodes (n=14). [SUP67]Ga scan detected 100% of the cases with subclinical involvement in the lungs. Scintigraphy was superior to chest radiography in demonstrating lung disease (94% vs 81%). The lymphatic lesions were demonstrated by [SUP67]Ga scan in all the clinically suspected cases and in nearly all unsuspected cases, and also revealed more extensive involvement than was clinically suspected in many of them. There was good agreement between [SUP67]Ga scan and the other imaging procedures for the initial detection of thoracic and abdominal lymph nodes and bone involvement. [SUP67]Ga imaging detected most cases of laryngopharyngeal disease with active inflammatory lesions found at indirect laryngoscopy. On the other hand, [SUP67]Ga scan failed to demonstrate most of the adrenal and CNS lesions detected by abdominal US/CT and head CT/MRI. In conclusion, [SUP67]Ga imaging is a useful tool for evaluating the location and extent of suspected and unsuspected lesions in PCM. It could serve as a screening method before the use of other diagnostic procedures, particularly in the detection of lung, superficial and deep lymph node and bone involvement. [ABSTRACT FROM AUTHOR]

Objective: To investigate the relation between atrophy of the hippocampal region and brain functional patterns during episodic memory processing in Alzheimer's disease.Patients and Methods: Whole brain structural magnetic resonance imaging (MRI) data and single photon emission computed tomography (SPECT) measures of regional cerebral blood flow (rCBF) were obtained during a verbal recognition memory task in nine subjects with mild Alzheimer's disease and 10 elderly healthy controls. Using the statistical parametric mapping approach, voxel based comparisons were made on the MRI data to identify clusters of significantly reduced grey matter concentrations in the hippocampal region in the Alzheimer patients relative to the controls. The mean grey matter density in the voxel cluster of greatest hippocampal atrophy was extracted for each Alzheimer subject. This measure was used to investigate, on a voxel by voxel basis, the presence of significant correlations between the degree of hippocampal atrophy and the rCBF SPECT measures obtained during the memory task.Results: Direct correlations were detected between the hippocampal grey matter density and rCBF values in voxel clusters located bilaterally in the temporal neocortex, in the left medial temporal region, and in the left posterior cingulate cortex during the memory task in the Alzheimer's disease group (p < 0.001). Conversely, measures of hippocampal atrophy were negatively correlated with rCBF values in voxel clusters located in the frontal lobes, involving the right and left inferior frontal gyri and the insula (p < 0.001).Conclusions: Hippocampal atrophic changes in Alzheimer's disease are associated with reduced functional activity in limbic and associative temporal regions during episodic memory processing, but with increased activity in frontal areas, possibly on a compensatory basis. [ABSTRACT FROM AUTHOR]

Abstract Objective – To investigate why bilateral parietotemporal hypoperfusion, the typical SPECT pattern of Alzheimer's disease (AD), occurs in some but not in all patients with probable AD. Methods – We reviewed the SPECT scans of 220 patients presenting with cognitive impairment. Among them, 104 patients fulfilled NINCDS–ADRDA criteria for probable AD, 48 (32 women) with early onset (before age of 65) and 56 (40 women) with late onset of the symptoms. Dementia severity was assessed by the Mini‐Mental State Examination. The SPECT scans were classified by visual inspection blind to clinical diagnoses. Results – Bilateral parietotemporal hypoperfusion was more frequent in patients with severe AD, in those with early onset of the symptoms, and in men. Duration of symptoms, type of gamma‐camera or radiopharmaceutical agent used were not associated with this SPECT pattern. Conclusion – These findings may be useful in the clinical setting and point to heterogeneity of AD according to age at onset. [ABSTRACT FROM AUTHOR]