Cranial magnetic resonance (MR) imaging was performed in 38 pregnant and postpartum women and 30 nonpregnant age-matched control subjects to establish standards for pituitary gland size and shape during this period. Gland height and infundibulum width were measured on midline T1-weighted sagittal images. Gland convexity or concavity was graded qualitatively. Throughout pregnancy, gland height increased linearly by approximately 0.08 mm/wk. No gland exceeded 10 mm in height during pregnancy. Increases in gland convexity also correlated with progression of pregnancy. The largest glands were seen in the immediate postpartum period; during this period, five of 12 glands measured 10.0-11.8 mm. Beyond the first week post partum, glands rapidly returned to normal size, apparently regardless of the status of breast-feeding. The mean diameter of the infundibulum was 2.2 mm (range, 0.8-4.0 mm). The pituitary gland enlarges throughout pregnancy but should probably not exceed 10 mm during most of this period. Size of up to 12 mm may be acceptable immediately post partum.
Cranial magnetic resonance (MR) imaging was performed on eight consecutive patients with generalized tonic-clonic seizures caused by eclampsia. Each patient underwent serial neurologic examinations until all symptoms resolved. Six of those eight patients underwent follow-up MR imaging. These patients were compared with those in previous case reports of MR imaging abnormalities of the brain in eclampsia. MR imaging typically demonstrates bilateral hyperintense lesions on T2-weighted images and iso- to hypointense lesions on T1-weighted images. MR imaging abnormalities are most commonly located in the distribution of the posterior cerebral circulation and are associated with visual disturbances. Basal ganglia and deep white matter lesions are less common and are associated with mental status changes. Most lesions seen at MR imaging in patients with eclampsia are reversible.
The clinical and radiological findings in 10 patients with cerebral venous occlusive disease are reported. Headache, confusion, and signs of increased intracranial pressure were the primary findings. Angiographic observations included nonvisualization of the dural sinuses, prolonged arteriovenous circulation time, dilated dural and venous collateral channels, and reversal of collateral flow. In such cases, retrograde jugular venography may show obstruction of the sinuses and intraluminal thrombus formation, confirming the diagnosis. The demonstration of angiographically nonvisualized unusual venous collaterals is also possible by this technique.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.