Pituitary apoplexy: diagnosis by computed tomography

Computed tomography (CT) now enables the early diagnosis of pituitary apoplexy. Since CT can detect blood, it can document acute or chronic hemorrhage in pituitary adenomas. In addition, CT can discriminate between densities other than blood and can therefore be used to diagnose those cases of pituitary apoplexy in which infarction and necrosis predominate. These conclusions were verified by a review of 10 apoplectic patients studied by CT. Although nine diagnostic delays occurred tissue confirmation by surgery in eight cases and autopsy on one made us familiar with the CT findings which should be useful in future diagnosis.

Arteriovenous malformation in the retina of a monkey

A vascular abnormality of the retina of a rhesus monkey was studied with fluorescein angiography, microvascular examination after silicone rubber injection, and histological examination. Fluorescein angiography revealed that this abnormality was an arteriovenous shunt. Microvascular examination showed a vascular abnormality on the sclera and an end-to-end communication of the arteriovenous malformation that was a continuation of abnormally large central retinal vessels observed just before their insertion into the optic nerve in the orbit. Histologic examination proved that the arteriovenous shunt originated from the central retinal vessels in the orbit; that degeneration of the retina and the choroid was extensive near the abnormal vessels; that the abnormal vessels had normal endothelium and adventitia but remarkably widened media; and that the cavernous hamangioma-like structure in the optic disk was clearly distinguishable from a cavernous hamangioma.

Spontaneous pneumoventriculogram following radiation of a pituitary adenoma

Three years after radiation therapy for an intrasellar tumor, a 42-year-old housewife presented with headache, lethargy, and remarkable plain skull roentgenograms, in which dilated lateral and third ventricles were filled with air. Air apparently had entered the cranium through the sphenoid sinus and eroded sellar floor, extending directly through intrasellar remnants of the chromophobe adenoma and into the floor of the third ventricle. Frontal exploration showed an empty sella turcica and no residual tumor. She made an excellent recovery and has done well for 5 years after operative closure of the defect.

The effect of arterial PO2 on relative retinal blood flow in monkeys

The relationship of blood oxygenation to retinal blood flow has been studies in rhesus monkeys. Constriction of major retinal arteries and veins during hyperoxia and dilation during hypoxia are demonstrated. Together with mean circulation times based on the technique of fluorescein densitometry curves, these data allow an estimation of retinal blood flow, which increases considerably in hypoxia and shows a moderate decrease in hyperoxia. These findings indicate that the retinal circulation parallels that of the brain in adjusting to changes in arterial PO2 with compensatory changes in blood flow.