Journal of neuroimaging : official journal of the American Society of Neuroimaging
-
Case Reports
Paradoxical brain embolism from thrombus associated with vena caval filter in a patient with cancer.
A 71-year-old man experienced sudden onset of hemiparesis and aphasia. He had a 4-month history of gallbladder cholangiocarcinoma, complicated with a postoperative deep-vein thrombosis (DVT) that necessitated a vena caval filter placement. Diffusion-weighted magnetic resonance imaging of the brain showed multiple hyperintense foci. ⋯ Abdominal computed tomography showed a thrombus in the inferior vena cava extending through the filters. A transcranial Doppler bubble study revealed the presence of a right-to-left shunt. Paradoxical cerebral embolism must be considered in patients with DVT who have new onset neurologic deficits even in the presence of a caval filter.
-
The authors report on a 32-year-old man with common variable immunodeficiency and high signal intensity in basal ganglia on T1-weighted images. No signal alteration on T2-weighted and postcontrast images was observed. The patient had elevated levels of manganese in the serum. The authors conclude that the unusual hyperintensity in the basal ganglia area on T1-weighted images resulted from manganese deposition due to liver dysfunction.
-
Collateral flow patterns are important risk factors for brain ischemia in the presence of internal carotid artery (ICA) stenosis or occlusion. Ophthalmic artery (OA) flow reversal, routinely studied by transcranial Doppler sonography, is an important marker for high-grade ICA stenosis or occlusion. The authors sought to define the value of assessing OA flow direction with color flow duplex ultrasonography (CDUS) in the setting of significant ICA disease. ⋯ OA flow direction is easily studied with CDUS. Reversed OA flow direction is highly specific (100%) for severe ipsilateral ICA stenosis or occlusion, with excellent positive predictive value, moderate negative predictive value, and limited sensitivity. OA flow reversal is not only quite specific for severe ICA disease, which may be helpful if the carotid CDUS is difficult or inadequate, but may also provide additional hemodynamic insights (i.e., the inadequacy of other collateral channels such as the anterior communicating artery). OA evaluation can provide important hemodynamic information and should be included as part of carotid CDUS if there is any evidence of ICA stenosis or occlusion.
-
Case Reports
Isolated pontine progressive multifocal leukoencephalopathy: unusual magnetic resonance imaging features.
Progressive multifocal leukoencephalopathy (PML) is an uncommon opportunistic infection that causes focal or multifocal demyelination predominantly in the subcortical white matter. The authors describe the clinical and radiographic features in 2 unusual cases of PML that were initially isolated to the pons. One patient presented clinically with only an isolated sixth cranial nerve palsy.
-
Septum pellucidum agenesis is frequently associated with other cerebral malformations. Its isolated agenesis is quite rare. In the literature, all reported cases were diagnosed in early childhood. The authors present an unusual case of isolated septum pellucidum agenesis detected in adulthood with computed tomography and magnetic resonance imaging.