Computer-aided diagnosis system for characterizing ISUP grade≥2 prostate cancers at multiparametric MRI: A cross-vendor evaluation.

PURPOSE: To assess the performance of a computer-aided diagnosis (CADx) system trained at characterizing International Society of Urological Pathology (ISUP) grade≥2 peripheral zone (PZ) prostate cancers on multiparametric magnetic resonance imaging (mpMRI) examinations from a different institution and acquired on different scanners than those used for the training database. PATIENTS AND METHODS: Preoperative mpMRIs of 74 men (median age, 65.7 years) treated by prostatectomy between 2014 and 2017 were retrospectively selected. One radiologist outlined suspicious lesions and scored them using Prostate Imaging-Reporting and Data System version 2 (PI-RADSv2); their CADx score was calculated using a classifier trained on an independent database of 106 patients treated by prostatectomy in another institution. The lesions' nature was assessed by comparison with prostatectomy whole-mounts. Diagnostic accuracy was estimated with areas under receiver operating characteristic curves (AUCs). Sensitivity and specificity were calculated using a CADx threshold (≥0.21) that yielded 95% sensitivity in the training database, and a PI-RADSv2≥3 threshold. RESULTS: A total of 127 lesions (PZ, n=104; transition zone [TZ], n=23) were described. In PZ, CADx and PI-RADSv2 scores had similar AUCs for characterizing ISUP grade≥2 cancers (0.78 [95% confidence interval (CI): 0.69-0.87] vs. 0.74 [95%CI: 0.62-0.82], respectively) (P=0.59). Sensitivity and specificity were respectively 89% (95%CI: 82-97%) and 42% (95%CI: 26-58%) for the CADx score, and 97% (95%CI: 93-100%) and 37% (95%CI: 22-52%) for the PI-RADSv2 score. In TZ, both scores showed poor specificity. CONCLUSION: In this external cohort, the CADx and PI-RADSv2 scores showed similar performances in characterizing ISUP grade≥2 cancers.

Effect of peripheral cryoneurotomy and nerve transection on the trigeminal ganglion in rats.

In this experimental study, we did peripheral neurectomyand peripheral cryoneurotomy of the mental nerve in rats and histologically assessed their effects on the trigeminal ganglion at timed intervals for six months. There were marked irreversible changes in the neurectomy group whereas the cryoneurotomy group made a full recovery. These results help to explain the differing effects of these procedures on trigeminal neuralgia.

Physical training induced resting bradycardia and its association with cardiac autonomic nervous activities.

Regular physical exercise causes resting bradycardia. This exercise-induced resting bradycardia may be associated with exercise-induced changes in Cardiac autonomic nervous activities (CANA). Power Spectral Analysis (PSA) of Heart rate variability (HRV) is one of the most promising new techniques to quantify CANA. Regular physical exercise induced bradycardia is associated with exercise-induced adaptation in CANA. To observe the HRV parameters by frequency domain method (PSA), in male adolescent athletes in order to find out the influence of regular physical exercise on resting heart rate (HR) and CANA. The cross sectional study was carried out on 62 adolescent male athletes aged 12-18 years (group B), in the Department of Physiology, Bangabandhu Sheikh Mujib Medical University from 1st July 2007 to 30th June 2008. For comparison 30 age, sex and socioeconomic condition matched apparently healthy sedentary subjects (group A) were also studied. The study group was selected from the BKSP (Bangladesh Krira Shikka Prothistan, Savar, Dhaka) and the control from a residential school of Dhaka city. HRV parameters were assessed by Polygraph (Polyrite D, version 2.2). For statistical analysis Independent-Samples t-test was done as applicable. Resting mean HR was significantly (p<0.001) lower in the athletes. The mean value of Total (variance), VLF, LF and HF power was significantly (p<0.001) higher in athletes than that of non-athetes. Regular physical exercise-induced resting bradycardia is associated with exercise-induced adaptation in cardiac autonomic nervous activities.

Antioxidant effect of valsartan in experimental model of myocardial infarction.

This study was done to investigate the antioxidant effect of valsartan, an AT1 receptor blocker, when administered in experimental model of myocardial infarction (MI). MI was induced in rats by administration of adrenaline at a dose of 2 mg/kg body weight subcutaneously two injections 24 hrs apart and was assessed by significant elevation of marker enzymes (CK-MB and AST). Valsartan (30 mg/kg body weight) was administered through intragastric tube daily for 2 weeks in both pre- and post- MI groups. Oxidative stress was assessed by the activities of malondialdehyde (MDA) level and reduced glutathione (GSH) level in erythrocytes. In both treated groups, valsartan caused significant recovery of the biochemical markers, GSH and MDA level. These findings suggest that pre- and post-treatment with valsartan had an anti-oxidant effect in patients who are at risk of acute myocardial infarction.

Computerized axial tomography in the diagnosis of internal derangements of the temporomandibular joint.

Fourteen patients with a history of pain, clicking and locking of the temporomandibular joint were assessed clinically and by using computerized axial tomography (CAT). The findings of the clinical and CAT scan assessment were correlated and compared with surgical observations. Computerized axial tomography scanning proved to be a highly accurate method of assessing meniscal position. With the advent of more sophisticated methods of CAT scanning, it provides an accurate, non-invasive method of assessing the temporomandibular joint and providing a basis for more effective treatment planning of problems related to internal derangements.

Solitary osteochondroma of T4 with thoracic cord compression.

A patient with a solitary osteochondroma of T4 presented with a five-year history of back pain and progressive paraparesis. Conventional and computed tomography delineated the tumor, which was totally removed via a thoracic laminectomy. Osteochondroma is an unusual cause of spinal cord compression.

Meningiomas of the pineal region and third ventricle.

The clinical presentation, radiological findings, and surgical management of two cases of meningioma arising from the velum interpositum without dural attachment are described. The true nature of these tumors was not suspected despite extensive preoperative diagnostic evaluation. A total removal was effected in both cases with the use of the operating microscope and a posterior fossa approach to the pineal region. A review of similar cases from the English literature is presented.

Cervical myelopathy and radiculopathy secondary to ossification of the posterior longitudinal ligament.

Ossification of the posterior longitudinal ligament, despite its rare occurrence in Caucasians, is one further cause of cervical myelopathy and radiculopathy that should be included in the differential diagnosis. A recent case is reported.

Obstructive hydrocephalus secondary to an ectatic basilar artery.

A 57 year-old white hypertensive male presented with a five-month history of progressive dementia and a clinical picture suggestive of normal pressure hydrocephalus. A CT scan and vertebral angiogram demonstrated an ectatic basilar artery obstructing the posterior third ventricle; the resulting hydrocephalus was relieved by a ventriculo-peritoneal shunt and the patient's symptoms resolved completely.

Diagnosis of empty sella with CT scan.

The diagnosis of empty sella was made correctly by CT scanning in 100% of 19 cases studied.

Complications of halo-pelvic traction. Case report.

When halo-pelvic traction is applied at a rapid rate it may induce cranial nerve palsies. The sixth, ninth, and tenth cranial nerves appear to be the most vulnerable. A proposed etiology is the stretching of these nerves resulting in a compromised blood supply with a consequent temporary paralysis which usually improves within 8 to 10 weeks.