Disinhibition in dementia related to reduced morphometric similarity of cognitive control network.

Disinhibition is one of the most distressing and difficult to treat neuropsychiatric symptoms of dementia. It involves socially inappropriate behaviours, such as hypersexual comments, inappropriate approaching of strangers and excessive jocularity. Disinhibition occurs in multiple dementia syndromes, including behavioural variant frontotemporal dementia, and dementia of the Alzheimer's type. Morphometric similarity networks are a relatively new method for examining brain structure and can be used to calculate measures of network integrity on large scale brain networks and subnetworks such as the salience network and cognitive control network. In a cross-sectional study, we calculated morphometric similarity networks to determine whether disinhibition in behavioural variant frontotemporal dementia (n = 75) and dementia of the Alzheimer's type (n = 111) was associated with reduced integrity of these networks independent of diagnosis. We found that presence of disinhibition, measured by the Neuropsychiatric Inventory Questionnaire, was associated with reduced global efficiency of the cognitive control network in both dementia of the Alzheimer's type and behavioural variant frontotemporal dementia. Future research should replicate this transdiagnostic finding in other dementia diagnoses and imaging modalities, and investigate the potential for intervention at the level of the cognitive control network to target disinhibition.

Usefulness of barium studies for differentiating benign and malignant strictures of the esophagus.

OBJECTIVE: The purpose of our investigation was to determine the usefulness of barium studies for differentiating benign and malignant strictures of the esophagus. MATERIALS AND METHODS: A search of radiology and endoscopy files revealed 100 patients with esophageal strictures on barium studies who underwent endoscopy (with endoscopic brushings or biopsy specimens in 57). The images from these barium studies were reviewed by two gastrointestinal radiologists who were unaware of the clinical, endoscopic, and pathologic findings; these observers classified the strictures as having a benign, malignant, or equivocal appearance. The radiographic data were correlated with the endoscopic and pathologic findings to determine the usefulness of barium studies for differentiating benign strictures from malignant tumor. RESULTS: Of the 100 esophageal strictures detected on barium studies, 75 (75%) had a benign radiographic appearance, 11 (11%) had a malignant appearance, and 14 (14%) had an equivocal appearance. None of the 75 patients with radiographically benign strictures had malignant tumor on endoscopy, which revealed benign strictures in 48 patients and no definite strictures in the remaining 27. Conversely, all 11 patients (100%) with radiographically malignant strictures had malignant tumor on endoscopy. Finally, 13 (93%) of 14 patients with radiographically equivocal strictures had benign strictures without tumor on endoscopy and one (7%) had esophageal carcinoma. CONCLUSION: Radiographically benign esophageal strictures are not found to be caused by malignant tumor on endoscopy, so these patients can be treated medically before endoscopy or endoscopic dilatation procedures are performed. However, radiographically malignant or equivocal strictures require early endoscopy and biopsy for a definitive diagnosis.