Multiclass brain tumor classification is performed by using a diversified dataset of 428 post-contrast T1-weighted MR images from 55 patients. These images are of primary brain tumors namely astrocytoma (AS), glioblastoma multiforme (GBM), childhood tumor-medulloblastoma (MED), meningioma (MEN), secondary tumor-metastatic (MET), and normal regions (NR). Eight hundred fifty-six regions of interest (SROIs) are extracted by a content-based active contour model. Two hundred eighteen intensity and texture features are extracted from these SROIs. In this study, principal component analysis (PCA) is used for reduction of dimensionality of the feature space. These six classes are then classified by artificial neural network (ANN). Hence, this approach is named as PCA-ANN approach. Three sets of experiments have been performed. In the first experiment, classification accuracy by ANN approach is performed. In the second experiment, PCA-ANN approach with random sub-sampling has been used in which the SROIs from the same patient may get repeated during testing. It is observed that the classification accuracy has increased from 77 to 91 %.PCA-ANN has delivered high accuracy for each class: A S -9 0 . 7 4 % , G B M -8 8 . 4 6 % , M E D -8 5 % , MEN-90.70 %, MET-96.67 %, and NR-93.78 %. In the third experiment, to remove bias and to test the robustness of the proposed system, data is partitioned in a manner such that the SROIs from the same patient are not common for training and testing sets. In this case also, the proposed system has performed well by delivering an overall accuracy of 85.23 %. The individual class accuracy for each class is: AS-86.15 %, GBM-65.1 %, MED-63.36 %, MEN-91.5 %, MET-65.21 %, and NR-93.3 %. A computer-aided diagnostic system comprising of developed methods for segmentation, feature extraction, and classification of brain tumors can be beneficial to radiologists for precise localization, diagnosis, and interpretation of brain tumors on MR images.
Neuropathy in rheumatoid arthritis (RA) may result secondary to entrapment, vasculitis, and drug toxicity. We aimed to study clinical and electrophysiological neuropathy and pathological changes in sural nerve in patients with RA. One hundred eight patients of RA, fulfilling American College of Rheumatology 1987 criteria (mean age, 45.83 years; M/F 1:3, 80.3% seropositive) were examined clinically and electrophysiologically for evidence of peripheral neuropathy. Sural nerve biopsies were performed in the involved cases. In all RA patient medications, disease activity, results of blood tests, and X-rays of affected joints were recorded. Twenty-three patients complained of paresthesias in the extremities. Vibration sensations were decreased in 9, and tendon reflexes were decreased or absent in 28 patients. Sixty-two (57.4%) patients had electrophysiologic evidence of neuropathy. Of these 53 (85.5%) patients had pure sensory or sensory motor axonal neuropathy (mononeuritis multiplex, n = 7), while 9 (14.5%) had demyelinating neuropathy (chronic inflammatory demyelinating polyneuropathy, n = 1). Carpal tunnel syndrome was seen in 11 (10.1%) patients (associated with neuropathy in 6). Of 23 sural nerve biopsies available, perineurial thickening (n = 5, amyloid deposits n = 4), perivascular lymphomononuclear cell infiltrate (n = 4), loss of myelin fibers (n = 2), and necrotizing vasculitis (n = 1) were found. Clinically, however, seven patients had evidence of cutaneous vasculitis. Comparing the clinical characteristics of the patients with or without electrophysiological neuropathy, absence of deep tendon jerks (p < 0.005) and presence of extra articular manifestations (p < 0.01) were conspicuous in the neuropathic group. There was no relation of neuropathy with the duration of RA, seropositivity, joint erosions, joint deformities, prior disease-modifying anti-rheumatic drugs or glucocorticoid intake, and 28-joint disease activity score. Neuropathy in RA was mostly subclinical and predominantly axonal. Pathologically, neuropathy secondary to amyloid infiltration was second only to vasculitic neuropathy. Absence of deep tendon jerks and presence of vasculitis were more commonly observed in patients with neuropathy.
Endovascular techniques currently form less invasive and first line treatment options in arterioportal/venous fistulae, surgery being reserved only for unsuccessful embolizations/complex fistulae.
Neurolymphomatosis (NL) defined as infiltration of the central nervous system or the peripheral nervous system (PNS) by malignant lymphoma cells is a rare clinical entity. However, the increasing use of fluorodeoxyglucose positron-emission tomography (FDG-PET) and magnetic resonance imaging in evaluating PNS disorders is resulting in; this condition being recognized more frequently. Here; we report five NL patients and review the current literature. We report five patients with non-Hodgkin's lymphoma (NHL) and NL, all of whom were men aged 47–69 years. The clinical presentation varied from symmetrical peripheral neuropathy to mononeuropathy. Peripheral neuropathy was the presenting manifestation of a systemic lymphoma in two patients (40%). Neuroimaging as well as whole-body FDG-PET helped in determining the correct diagnosis in all of the patients. NL is an unusual presentation of NHL resulting from infiltration of the PNS by malignant lymphomatous cells. While evaluating peripheral neuropathy, a high degree of suspicion of NL is required since the presenting symptoms vary, conventional radiology has only modest sensitivity, and a pathological diagnosis is often difficult. FDG-PET helps in the early diagnosis and treatment of this condition.
OBJECTIVES:Decreased magnetization transfer ratio (MTR) in the brain characterizes cerebral edema (CE) in patients with liver cirrhosis, but the role of treatment on its reversibility has not been studied in patients who have minimal hepatic encephalopathy (MHE). This study was carried to evaluate the reversibility of CE with lactulose and rifaximin treatment in patients with MHE and role of ammonia, pro-inflammatory interleukins (IL-1, IL-6) and tumor necrosis factor (TNF)-α in its pathogenesis.METHODS:Twenty-three patients with cirrhosis (14 with MHE, 9 without MHE (NMHE)) and 6 healthy controls underwent ammonia, IL-1, IL-6, TNF-α estimation, and MTR in frontal white matter (FWM), parietal white matter (PWM), internal capsule (IC), and basal ganglia (BG).RESULTS:Ammonia was significantly higher in the cirrhosis group compared with controls and in MHE compared with the NMHE group. Ammonia correlated positively with IL-1 and IL-6. MTRs in FWM, PWM, IC, and BG were significantly lower in the MHE group compared with controls and in PWM, IC, and BG compared with the NMHE group. MHE patients showed significant MTR increase in FWM, PWM, and IC with treatment. IL-6 and ammonia had significant negative and significant positive psychometric hepatic encephalopathy score (PHES) correlation with MTR in various regions.CONCLUSIONS:This study, for the first time, demonstrated the reversibility of low-grade CE with treatment in patients with MHE. Negative correlation between ammonia, IL-6 levels, and MTR and positive correlation between PHES and MTR in MHE patients suggests the role of inflammation and ammonia in the genesis of low-grade CE.
This study was carried out to ascertain the frequency of normal head computed tomography (CT) scans and positive CT scan findings in patients having chronic headache as chief complaint. Head CT scans done over a period of two years were retrospectively evaluated. On the basis of CT reports, the patients were divided into two groups: Group A, having headache as the only complaint, and Group B, having headache and additional neurological signs or symptoms. A total of 2498 patient reports were evaluated. There were 1772 patients in Group A and 726 patients in Group B. In Group A, 82% (n=1453) patients had normal head CT, whereas in Group B 74.5% (n=541) patients had a normal CT scan. There were 13.22% head CT scans showing significant findings in Group B, as compared to 6.2% in Group A. Both these differences were found to be statistically significant. CT findings such as infections, neoplasm, hydrocephalus, and extra-axial collections were higher in Group B when compared to Group A. CT examination in patients with isolated chronic headache is normal in high percentage of patients. The frequency and distribution of various CT findings over different age groups in a large cohort of patients presenting with chronic headache are discussed.
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