Magnetic resonance imaging in intracranial paracoccidioidomycosis.

Paracoccidioidomycosis is a systemic mycosis, endemic in South and Central America, that affects the central nervous system (CNS) in almost 10% of patients. Neurological involvement includes two different clinical forms: meningeal and granulomatous, also known as the pseudotumor form. Five patients with biopsy-proved systemic paracoccidioidomycosis and neurological complaints were studied by magnetic resonance imaging. CNS involvement was detected in all patients in the form of multiple round or lobulated lesions, predominantly hypointense on T2-weighted images and ring or nodular enhancement on post-gadolinium T1-weighted images. The lesions were distributed diffusely, with a slight predominance in the supratentorial compartment, although infratentorial lesions were also observed, mainly in the cerebellum. Hypointense lesions on T2-weighted images persisted in all 3 patients reexamined after treatment, whereas enhancing lesions on post-gadolinium T1-weighted images turned isointense in 2 patients. Magnetic resonance imaging is a sensitive method in documenting CNS paracoccidioidomycosis, most frequently as supratentorial and infratentorial multiple, round or lobulated hypointense lesions on T2-weighted images.

Correlations of nuclear magnetic resonance imaging, computerized tomography, and clinical profiles in multiple sclerosis.

Nuclear magnetic resonance (NMR) imaging was superior to CT for imaging the brain lesions of 27 patients with MS. The incidence of abnormal examinations was 78% by NMR and 63% by CT. In cases in which both studies were abnormal, NMR usually demonstrated many more lesions and more extensive involvement than CT. The appearance and locations of lesions identified by NMR were similar to those of autopsy studies of MS and may be relatively specific for this disease. Some lesions identified by CT disappeared during serial examinations, but lesions identified by NMR did not resolve over time. Seventy-five percent of the lesions were clinically "silent"; only 5% were definitely related to the clinical symptoms and signs. All of those lesions were located in the brainstem or cerebellar peduncles and were identified by NMR, but missed by CT.

Subcortical arteriosclerotic encephalopathy (Binswanger's disease). Computed tomographic, nuclear magnetic resonance, and clinical correlations.

Twenty-three elderly patients were found to have a consistent pattern of leukoencephalopathy by computed tomography and nuclear magnetic resonance imaging. Eight patients presented with vague, nonspecific symptoms and had no neurologic deficits. The other 15 patients had neurologic deficits that presented in one of three ways: stroke, seven patients; slowly progressive dementia and gait disturbance, five patients; or slowly progressive dementia alone, three patients. Risk factors for arteriosclerosis (hypertension, diabetes) were present in 18 patients (78%). The necropsy of one patient revealed arteriosclerotic vasculopathy characteristic of subcortical arteriosclerotic encephalopathy (SAE) or Binswanger's disease. Subcortical arteriosclerotic encephalopathy may be a relatively common affliction of elderly patients, most of whom have risk factors for arteriosclerosis. The modes of presentation and associated clinical signs are variable, and more than one third may have no neurologic deficit. In some cases SAE overlaps with normal pressure hydrocephalus by clinical and neuroimaging criteria. Some patients with normal pressure hydrocephalus who do not respond to ventricular shunting may actually have SAE.