Electrostimulation mapping of comprehension of auditory and visual words.

In order to spare functional areas during the removal of brain tumours, electrical stimulation mapping was used in 90 patients (77 in the left hemisphere and 13 in the right; 2754 cortical sites tested). Language functions were studied with a special focus on comprehension of auditory and visual words and the semantic system. In addition to naming, patients were asked to perform pointing tasks from auditory and visual stimuli (using sets of 4 different images controlled for familiarity), and also auditory object (sound recognition) and Token test tasks. Ninety-two auditory comprehension interference sites were observed. We found that the process of auditory comprehension involved a few, fine-grained, sub-centimetre cortical territories. Early stages of speech comprehension seem to relate to two posterior regions in the left superior temporal gyrus. Downstream lexical-semantic speech processing and sound analysis involved 2 pathways, along the anterior part of the left superior temporal gyrus, and posteriorly around the supramarginal and middle temporal gyri. Electrostimulation experimentally dissociated perceptual consciousness attached to speech comprehension. The initial word discrimination process can be considered as an "automatic" stage, the attention feedback not being impaired by stimulation as would be the case at the lexical-semantic stage. Multimodal organization of the superior temporal gyrus was also detected since some neurones could be involved in comprehension of visual material and naming. These findings demonstrate a fine graded, sub-centimetre, cortical representation of speech comprehension processing mainly in the left superior temporal gyrus and are in line with those described in dual stream models of language comprehension processing.

Gamma Knife Surgery versus Linac for Brain Metastasis: Which Technique for Which Patient? Analysis of an Historical Cohort of 63 Consecutive Patients Harboring 130 Lesions

Objectives: We present the retrospective analysis of a single-institution experience for radiosurgery (RS) in brain metastasis (BM) with Gamma Knife (GK) and Linac. Methods: From July 2010 to July 2012, 28 patients (with 83 lesions) had RS with GK and 35 patients (with 47 lesions) with Linac. The primary outcome was the local progression-free survival (LPFS). The secondary outcome was the overall survival (OS). Apart a standard statistical analysis, we included a Cox regression model with shared frailty, to modulate the within-patient correlation (preliminary evaluation showed a significant frailty effect, meaning that the correlation within patient could be ignored). Results: The mean follow-up period was 11.7 months (median 7.9, 1.7-22.7) for GK and 18.1 (median 17, 7.5-28.7) for Linac. The median number of lesions per patient was 2.5 (1-9) in GK compared with 1 (1-3) in Linac. There were more radioresistant lesions (melanoma) and more lesions located in functional areas for the GK group. The median dose was 24 Gy (GK) compared with 20 Gy (Linac). The LPFS actuarial rate was as follows: for GK at 3, 6, 9, 12, and 17 months: 96.96, 96.96, 96.96, 88.1, and 81.5%, and remained stable till 32 months; for Linac at 3, 6, 12, 17, 24, and 33 months, it was 91.5, 91.5, 91.5, 79.9, 55.5, and 17.1%, respectively (p = 0.03, chi-square test). After the Cox regression analysis with shared frailty, the p-value was not statistically significant between groups. The median overall survival was 9.7 months for GK and 23.6 months for Linac group. Uni- and multivariate analysis showed a lower GPA score and noncontrolled systemic status were associated with lower OS. Cox regression analysis adjusting for these two parameters showed comparable OS rate. Conclusions: In this comparative report between GK and Linac, preliminary analysis showed that more difficult cases are treated by GK, with patients harboring more lesions, radioresistant tumors, and highly functional located. The groups look, in this sense, very heterogeneous at baseline. After a Cox frailty model, the LPFS rates seemed very similar (p < 0.05). The OS was similar, after adjusting for systemic status and GPA score (p < 0.05). The technical reasons for choosing GK instead of Linac were the anatomical location related to highly functional areas, histology, technical limitations of Linac movements, especially lower posterior fossa locations, or closeness of multiple lesions to highly functional areas optimal dosimetry with Linac

A New Symptom, 'Palinendophonia', Associated with Pure Verbal Palinacousis Induced by a Right Inferior Temporal Lesion.

We describe the case of a patient with pure verbal palinacousis and perseveration of inner speech after a right inferior temporal lesion. The superior temporal lobe, including the superior temporal sulcus and the interhemispheric connection between the 2 superior temporal lobes, explored by tractography, were preserved. These regions are involved in voice processing, verbal short-term memory and inner speech. It can then be hypothesised that abnormal activity in this network has occurred. Palinacousis and 'palinendophonia', a term proposed for this symptom not previously reported, may be due to common cognitive processes disorders involved in both voice hearing and inner speech.

Right heart ischemia in cases of sepsis.

Data from the literature suggest that cases of sepsis complicated by right ventricular (RV) dysfunction have poorer prognosis. In these cases progressive hypoperfusion associated to increasing, injury-related, pulmonary vascular resistance account for RV ischemia. In the present analysis, we wanted to evaluate whether prevalent RV cardiac ischemic damage could be detected in a series of fatal sepsis cases. We retrospectively investigated 20 cases of sepsis that underwent forensic autopsy (study group-11♀, 9♂, mean age 57 years) and compared them to a group of 20 cases of hanging (hanging group-4 ♀, 16 ♂, mean age 44 years) as well as to a group of 20 cases of myocardial infarction (MI group-9 ♀, 11 ♂, mean age 65 years), as examples of cardiac damage due to global hypoxia during agony and ischemic damage, respectively. We performed immunohistochemistry with the antibodies anti-fibronectin and C5b-9. The reactions were semiquantitively classified and the groups were compared. In 30% of the cases of sepsis prevalent RV ischemic damage could be detected with the antibody anti-fibronectin. This expression was significantly different from that observed in cases of MI (p=0.028) and hanging (p<0.001). Our study showed that, in cases of fatal sepsis, prevalent RV ischemic damage occurred in a substantial minority of cases.

Impact of 18F-FDG PET scan on the prevalence of benign thoracic lesions at surgical resection

OBJECTIVE: The main utility of 18-fluorodeoxyglucose positron emission tomography (FDG-PET) lies in the staging of lung cancer. However, it can also be used to differentiate indeterminate pulmonary lesions, but its impact on the resection of benign lesions at surgery is unknown. The aim of this study was to compare the prevalence of benign lesions at thoracotomy carried out for suspected lung cancer, before and after the introduction of PET scanning in a large thoracic surgical centre. MATERIALS AND METHODS: We reviewed our prospectively recorded surgical database for all consecutive patients undergoing thoracotomy for suspected or proven lung cancer and compared the prevalence of benign lesions in 2 consecutive 2-year groups, before (group I) and after (group II) the introduction of FDG-PET scan respectively. RESULTS: Surgical resection was performed on 1233 patients during the study period. The prevalence of benign lesions at surgery in groups I and II was similar (44/626 and 41/607, both 7%), and also in group II between those who underwent FDG-PET scan and the remainder (21/301 and 20/306 respectively, both 7%). In group II, of the 21 patients with benign lesions, who underwent FDG-PET, 19 had a false positive scan (mean standardised uptake value 5.3 [range 2.6-12.7]). Of these, 13 and 4 patients respectively had non-diagnostic bronchoscopy and percutaneous transthoracic lung biopsy pre thoracotomy. There was no difference in the proportion of different benign lesions resected between group I and those with FDG-PET in group II. CONCLUSION: The introduction of FDG-PET scanning has not altered the proportion of patients undergoing thoracotomy for ultimately benign lesions, mainly due to the avidity for the isotope of some non-malignant lesions. Such false positive results need to be considered when patients with unconfirmed lung cancer are contemplated for surgical resection.

Connectivity and tissue microstructural alterations in right and left temporal lobe epilepsy revealed by diffusion spectrum imaging.

Focal epilepsy is increasingly recognized as the result of an altered brain network, both on the structural and functional levels and the characterization of these widespread brain alterations is crucial for our understanding of the clinical manifestation of seizure and cognitive deficits as well as for the management of candidates to epilepsy surgery. Tractography based on Diffusion Tensor Imaging allows non-invasive mapping of white matter tracts in vivo. Recently, diffusion spectrum imaging (DSI), based on an increased number of diffusion directions and intensities, has improved the sensitivity of tractography, notably with respect to the problem of fiber crossing and recent developments allow acquisition times compatible with clinical application. We used DSI and parcellation of the gray matter in regions of interest to build whole-brain connectivity matrices describing the mutual connections between cortical and subcortical regions in patients with focal epilepsy and healthy controls. In addition, the high angular and radial resolution of DSI allowed us to evaluate also some of the biophysical compartment models, to better understand the cause of the changes in diffusion anisotropy. Global connectivity, hub architecture and regional connectivity patterns were altered in TLE patients and showed different characteristics in RTLE vs LTLE with stronger abnormalities in RTLE. The microstructural analysis suggested that disturbed axonal density contributed more than fiber orientation to the connectivity changes affecting the temporal lobes whereas fiber orientation changes were more involved in extratemporal lobe changes. Our study provides further structural evidence that RTLE and LTLE are not symmetrical entities and DSI-based imaging could help investigate the microstructural correlate of these imaging abnormalities.

Positive predictive values of Breast Imaging Reporting and Data System (BI-RADS®) categories 3, 4 and 5 in breast lesions submitted to percutaneous biopsy

Objective To evaluate the BI-RADS as a predictive factor of suspicion for malignancy in breast lesions by correlating radiological with histological results and calculating the positive predictive value for categories 3, 4 and 5 in a breast cancer reference center in the city of São Paulo. Materials and Methods Retrospective, analytical and cross-sectional study including 725 patients with mammographic and/or sonographic findings classified as BI-RADS categories 3, 4 and 5 who were referred to the authors' institution to undergo percutaneous biopsy. The tests results were reviewed and the positive predictive value was calculated by means of a specific mathematical equation. Results Positive predictive values found for categories 3, 4 and 5 were respectively the following: 0.74%, 33.08% and 92.95%, for cases submitted to ultrasound-guided biopsy, and 0.00%, 14.90% and 100% for cases submitted to stereotactic biopsy. Conclusion The present study demonstrated high suspicion for malignancy in lesions classified as category 5 and low risk for category 3. As regards category 4, the need for systematic biopsies was observed.

Screening of breast lesions: a comparative study between mammography, B-mode ultrasonography, sonoelastography and histological results

Objective To compare the capacity of mammography, sonoelastography, B-mode ultrasonography and histological analysis to differentiate benign from malignant breast lesions. Materials and Methods A total of 12 histopathologically confirmed breast lesions were documented. The lesions were assessed by means of mammography, B-mode ultrasonography and sonoelastography, and histopathological analysis was utilized as a gold standard. Sensitivity and specificity were calculated. A receiver operating characteristic (ROC) curve was constructed to evaluate the diagnostic performance of the mentioned techniques. Results Sensitivity and specificity in the differentiation between benign and malignant lesions were respectively 100% and 50% for mammography, 100% and 71% for B-mode ultrasonography, and 67% and 83% for sonoelastography. The area under the ROC curve was calculated for the three imaging modalities and corresponded to 0.792 for mammography, 0.847 for B-mode ultrasonography, and 0.806 for sonoelastography. Conclusion Sonoelastography demonstrated higher specificity and lower sensitivity as compared with mammography and B-mode ultrasonography. On the other hand, B-mode ultrasonography had the largest area under the ROC curve. Sonoelastography has demonstrated to be a promising technique to detect and evaluate breast lesions, and could potentially reduce the number of unnecessary biopsies.

Assessment of intima-media complex in carotid, femoral and right subclavian arteries for early investigation of atherosclerosis in HIV-infected patients

Objective To compare automatic and manual measurements of intima-media complex (IMC) in common carotid, common femoral and right subclavian arteries of HIV-infected patients in relation to a control group, taking into consideration the classical risk factors for atherosclerosis. Materials and Methods The study sample comprised 70 HIV-infected patients and 70 non-HIV-infected controls paired according sex and age. Automatic (gold standard) and manual measurements of IMC were performed in the carotid arteries. Manual measurements were also performed in common femoral and right subclavian arteries. Bland-Altman graphs were utilized in the comparison and the adopted level significance was 5%. Results Intima-media complex alterations were not observed in any of the individuals as the mean automatic measurement in the right common carotid (RCC) artery was considered as the gold standard. As the gold standard was compared with the manual measurements (mean, maximum and minimum), no clinically significant alteration was observed. As the gold standard was compared with other sites, the difference was statistically and clinically significant at the origin of right subclavian artery (RCC: 0.51 mm vs. 0.91 mm) (p < 0.001). Conclusion HIV-infected individuals are not at higher risk for atherosclerosis than the control population.