Correlation between anatomic landmarks and fMRI in detection of the sensorimotor cortex in patients with structural lesions

BACKGROUND: Structural lesions in/near the sensorimotor cortex may cause distortion/obscuration of the anatomic landmarks. PURPOSE: To compare the localization of the sensorimotor cortex using anatomical landmarks and fMRI in the clinical setting in patients with structural lesions in/near the central sulcus. MATERIAL AND METHODS: We analyzed the anatomic and fMRI data of 68 consecutive patients (42 tumors, 15 gliotic lesions, 11 focal cortical dysplasias [FCD]) who underwent MRI to assess the relationship of these lesions to the sensorimotor cortex. Anatomical data was analyzed on conventional two- and three-dimensional sequences. BOLD fMRI was performed with block design hand/leg or lip movement paradigm and general linear model was used for detecting the activated cortex. fMRI was considered as a valid method for identifying the sensorimotor cortex based on previously reported literature. RESULTS: The sensorimotor cortex could not be identified with anatomical landmarks in 9/68 (13.2%) patients. fMRI detected activation in areas different from that predicted by anatomical landmarks in 11/68 (16.2%) cases. This occurred in 5/42 (11.9%) tumors, 6/15 (40%) gliotic lesions, and 0/11 (0%) FCDs. The kappa value for concordance between fMRI and anatomic landmarks was 0.883 overall, 1.0 for tumors, 0.721 for gliotic lesions, and in none of the patients with focal cortical dysplasias. CONCLUSION: In patients with lesions that obscure normal cerebral landmarks, fMRI supplies the information that is not available from the anatomic images. In patients with landmarks that can be recognized, the location of the rolandic cortex may be misjudged in some cases if functional imaging is not used. Anatomic landmarks may not correlate with the area of functional activation in gliotic lesions and tumors. Determining the risk of a postoperative neurologic defect from surgery is likely to be more reliable with functional imaging than with conventional anatomic imaging

Advanced MRI in Rosai–Dorfman disease: Correlation with histopathology

Rosai-Dorfman disease is an idiopathic benign lymphoproliferative disorder that can, on rare occasions, cause intracranial or intraspinal lesions with non-specific features on conventional imaging. For this reason, its diagnosis is based on the classical pathological findings of histiocyte proliferation and emperipolesis. In this case report, we describe the imaging features of Rosai-Dorfman disease as visualized by newer types of MRI sequences, such as diffusion tensor imaging (DTI), susceptibility-weighted imaging (SWI) and perfusion-weighted imaging (PWI). In fact, combining the findings of conventional cross-sectional imaging with high fractional anisotropy (FA), a low apparent diffusion coefficient (ADC), mild blooming on SWI and decreased perfusion can help to make the diagnosis of Rosai-Dorfman disease. These newer tools can also be used to clarify the pathology of Rosai-Dorfman disease. (C) 2010 Elsevier Masson SAS. All rights reserved

Tumefactive demyelinating lesions: A Clinicopathological correlative study

Tumefactive demyelinating (TDL) lesions are focal zones of demyelination in the central nervous system and they often mimic the neuroimaging features of an intraxial neoplasm. In this report we describe the clinical, neuroimaging and neuropathological features of six cases of TDL. Only in two patients the neuroimaging features in MRI (magnetic resonance imaging) scans were suggestive of TDL while in the other four cases a diagnosis of glioma was suggested. In order to establish a confirmatory diagnosis neuronavigation/stereotactic biopsy was undertaken and the diagnosis of TDL was established in all six cases at histopathology. Two out of six patients did not respond to the conventional corticosteroid therapy and they were treated with plasma exchange. It is being concluded that neuronavigation biopsy, though provide only a small amount of tissue, and is extremely useful in making the diagnosis of TDL

An Education Initiative Modifies Opinions of Hemodialysis Nurses towards Home Dialysis

Background: It has been shown that in-center hemodialysis (HD) nurses prefer in-center HD for patients with certain characteristics; however it is not known if their opinions can be changed. Objective: To determine if an education initiative modified the perceptions of in-center HD nurses towards home dialysis. Design: Cross-sectional survey of in-center HD nurses before and after a three hour continuing nursing education (CNE) initiative. Content of the CNE initiative included a didactic review of benefits of home dialysis, common misconceptions about patient eligibility, cost comparisons of different modalities and a home dialysis patient testimonial video. Setting: All in-center HD nurses (including those working in satellite dialysis units) affiliated with a single academic institution Measurements: Survey themes included perceived barriers to home dialysis, preferred modality (home versus in-center HD), ideal modality distribution in the local program, awareness of home dialysis and patient education about home modalities. Methods: Paired comparisons of responses before and after the CNE initiative. Results: Of the 115 in-center HD nurses, 100 registered for the CNE initiative and 89 completed pre and post surveys (89% response rate). At baseline, in-center HD nurses perceived that impaired cognition, poor motor strength and poor visual acuity were barriers to peritoneal dialysis and home HD. In-center HD was preferred for availability of multidisciplinary care and medical personnel in case of catastrophic events. After the initiative, perceptions were more in favor of home dialysis for all patient characteristics, and most patient/system factors. Home dialysis was perceived to be underutilized both at baseline and after the initiative. Finally, in-center HD nurses were more aware of home dialysis, felt better informed about its benefits and were more comfortable teaching in-center HD patients about home modalities after the CNE session. Limitations: Single-center study Conclusions: CNE initiatives can modify the opinions of in-center HD nurses towards home modalities and should complement the multitude of strategies aimed at promoting home dialysis