Acute hemorrhagic leukoencephalitis: a cause of acute brainstem dysfunction.

A 37-year-old female physician was admitted to the hospital with severe headache, facial and hand paresthesias, dysarthria, and ataxia. Neurologic examination disclosed signs of brain stem dysfunction. There was rapid neurologic deterioration, and she died in 28 hours. Postmortem studies showed the characteristic features of acute hemorrhagic leukoencephalitis.

Extracranial carotid artery. Current concepts of diagnosis and management.

Extracranial carotid artery disease is a frequent cause of transient ischemic attack (about 50%), but a much less common cause of cerebral infarction (about 15%). Transient ischemic attack almost invariably precedes strokes caused by extracranial carotid stenosis, but rarely heralds strokes that result from cardiogenic embolism or intracranial vascular disease. When extracranial carotid stenosis produces a transient ischemic attack or stroke, artery-to-artery embolism is the predominant mechanism. Asymptomatic significant (>50%) carotid stenosis poses special clinical questions in patients scheduled to undergo general surgical or major cardiovascular operations. With general surgical procedures, there is no increased risk of stroke. With cardiovascular operations, however, there may be an increased risk of stroke in patients with critical (>90%) carotid stenosis or occlusion. When perioperative stroke occurs, the most common cause is embolism rather than focal hemodynamic change. For symptomatic high-grade (>70%) extracranial carotid stenosis, carotid endarterectomy is the treatment of choice in patients who are not high-risk surgical candidates. Alternatively, for high-risk patients, new drugs such as ticlopidine appear quite promising, and percutaneous angioplasty may also prove effective. Prevention of stroke must continue to be a major goal of national medical policy. Because cigarette smoking is the most important risk factor for extracranial carotid disease, more strenuous efforts must be directed toward eliminating this health risk.

Polyradiculoneuropathy in transfusion-associated AIDS and dorsal root pathology.

A 68-year-old woman developed a clinical picture of a painful subacute polyradiculoneuropathy. Her condition improved dramatically after treatment with plasmapheresis. A few months later she was found to have serologic evidence for the human immunodeficiency virus. This infection was traced to a contaminated transfusion received three years earlier. Postmortem studies disclosed pathology affecting mainly dorsal roots.

Takayasu's arteritis: diagnostic considerations and surgical treatment.

A 20-year-old white woman with Takayasu's arteritis had headaches, neck soreness, and a right carotid bruit. Corticosteroid treatment only temporarily relieved symptoms and caused Cushing's syndrome because of high dosage requirements. Progressive narrowing of the right common carotid artery occurred despite treatment. The diseased portion of the artery was successfully resected and replaced by a Dacron graft. Corticosteroid treatment was then tapered and discontinued, and the patient has remained well for 3 years. Carotid Doppler and real-time ultrasound studies performed more than 2 years after surgery showed a patent graft and no new disease process. This technique may be of value in selected cases for both prevention of cerebral ischemia and the elimination of local symptoms of the inflammatory process.

Reversible angiography.

A 26 year old woman presented with a subacute onset of headache, hypertension, and neurologic impairment. Angiography revealed severe extracranial carotid and vertebral artery disease. Long segmental stenoses, lumen irregularities, and aneurysmal dilatations were noted. She improved with medical management and was followed for one year. Because recurrent neurologic symptoms developed, angiography was repeated and disclosed normal vasculature. "Spontaneous dissections" with recovery are the most probable explanation for this phenomenon.

Downbeat nystagmus due to anticonvulsant toxicity.

Isolated downbeat nystagmus was observed in 2 patients on multiple anticonvulsant regimens. The nystagmus disappeared when phenytoin dosage was reduced. Electrooculographic analysis revealed impaired downward tracking, supporting the concept of "pursuit" nystagmus.

Glossopharyngeal neuralgia, asystole, and seizures.

Glossopharyngeal neuralgia, asystole, and seizures occurred in a patient with an internal carotid occlusion and external carotid stenosis. Swallowing was the triggering mechanism for these events. Mechanical stimulation of the pharynx failed to reproduce the symptoms. An ischemic injury to the glossopharyngeal nerve in the region of the jugular foramen that resulted in an artificial synapse is the proposed etiology.

Lightning eye movements.

Physiologic studies were performed on a patient who demonstrated lightning eye movements, palatal myoclonus and myoclonic jerks of the left platysma and sternocleidomastoid muscles. The myoclonus and lightning eye movements were separate phenomena with no defined relationship to each other. Analysis of this ocular dyskinesia identified strictly horizontal saccadic oscillations, 2 to 5 Hz in frequency, with amplitudes varying greatly but often reaching 25 degrees. A brief stationary period between each saccadic oscillation was frequently observed. They were particularly induced by vertical or horizontal ocular pursuit as well as sustained upward or downward ocular deviation. Caloric nystagmus abolished the oscillations but they persisted, irregularly, during optokinetic nystagmus. Thus a faulty visual fixation mechanism is postulated to precipitate lightning eye movements. Constrast studies revealed a mass lesion arising from the right dorsolateral portion of the medulla. These results indicate that lightning eye movements occur with caudal as well as rostral brain-stem lesions. From the clinical findings cerebellar pathway involvement is likely.

"Saccadic nystagmus" in cerebellar cortical atrophy.

An ocular dyskinesia designated "saccadic nystagmus" was observed in a patient with cerebellar cortical atrophy. Saccadic nystagmus is a sustained ocular dyskinesia present during visual fixation and abolished by eye closure. It is difficult to distinguish visually from either pendular or jerk nystagmus without eye movement recordings. The oscillations are horizontal and rapid and may be influenced by direction of gaze. Caloric nystagmus (eye closed) and optokinetic nystagmus were normal in our patient. Visual fixation abolished caloric nystagmus, which was replaced by saccadic nystagmus.