Sex differences in intracranial arterial bifurcations.

Background: Subarachnoid hemorrhage (SAH) is a serious condition, occurring more frequently in females than in males. SAH is mainly caused by rupture of an intracranial aneurysm, which is formed by localized dilation of the intracranial arterial vessel wall, usually at the apex of the arterial bifurcation. The female preponderance is usually explained by systemic factors (hormonal influences and intrinsic wall weakness); however, the uneven sex distribution of intracranial aneurysms suggests a possible physiologic factor-a local sex difference in the intracranial arteries.

[Treatment practice in primary hyperparathyroidism].

Background: A recent study found considerable regional differences in treatment of primary hyperparathyroidism in Norway. There is no consensus on specific indications for operation in these patients. We surveyed opinions among Norwegian endocrine surgeons and endocrinologists on the indications for surgical treatment of primary hyperparathyroidism.