Douglas H Yock

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Bilateral periventricular nodular heterotopia (BPNH) is a recently recognized malformation of neuronal migration, and perhaps proliferation, in which nodular masses of gray matter line the walls of the lateral ventricles. Most affected individuals have epilepsy and normal intelligence with no other congenital anomalies. A striking skew of the sex ratio has(More)
Radiation-induced meningiomas rarely have latency periods short enough from the time of irradiation to the clinical presentation of the tumor to present in the pediatric patient. Three cases of radiation-induced intracranial meningiomas in pediatric patients are presented. The first involved a meningioma of the right frontal region in a 10-year-old boy 6(More)
The anatomic correlates of speech fluency were studied in 54 right-handed patients with aphasia due to stroke. Speech fluency was assessed at 1 month postonset and then monthly for 5 months. CTs obtained at 5 months postonset were used for lesion localization and volume determination. Persistent nonfluency was associated with lesions in the rolandic(More)
Modern imaging techniques define the anatomic region infected and the evolution of the disease, help to evaluate treatment efficacy, and frequently can help to determine extra-central nervous system sources of infection, such as sinusitis or mastoiditis. These techniques are discussed by anatomic region, and differential diagnosis based on image pattern is(More)
Thirty-seven cranial computed tomography (CCT) scans of proved or highly probable recent ischemic brain infarcts were analyzed visually and numerically, with results organized by infarct age. The lesions typically appeared as homogeneous low density abnormalities, with no significant difference in scan characteristics between infarct age groups, i.e., it(More)
  • D H Yock
  • 1981
Four cases of cerebral emboli diagnosed on computed tomography as foci of increased density are discussed. The emboli were calcified in at least two cases. Both cardiac and carotid sources contributed dense emboli, which were seen to lodge at typical scan sites: near the anterior cerebral artery bifurcation (two cases) and in the middle cerebral artery(More)
  • D H Yock
  • 1984
1 Fenestration of cerebral arteries is a rare anomaly sometimes accompanied by a small proximal aneurysm. Our patient was seen with subarachnoid hemorrhage from a fenestration-aneurysm of the supraclinoid internal carotid artery (ICA). A 41-year-old woman was seen at an outside hospital with acute onset of an "exploding" headache accompanied by nausea,(More)
Nine patients with redundant lumbar nerve root syndrome were identified using positive-contrast myelography, seven with metrizamide and two with iophendylate. Serpiginous intradural filling defects occurred in conjunction with a complete or partial extradural block and spinal stenosis. These redundant nerve roots were seen on the cephalic side of the block.(More)
A case of subarachnoid hematoma after a difficult lumbar puncture and anticoagulation is presented. Subarachnoid adhesions preventing the free flow of spinal fluid at the T-6 level served to limit the cranial progression of the hemorrhage and produced a transverse myelopathy at that level. The underlying pathology, clinical course, and myelographic findings(More)
B-mode, real-time ultrasonic imaging was prospectively evaluated as a screening test for atherosclerotic occlusive vascular disease in the carotid bifurcation region, as defined by carotid angiography in 100 carotid systems in 50 patients. Preliminary reliability studies for each technique assessed agreement between examiners. Sensitivities of(More)