Pituitary apoplexy

Abstract

Pituitary apoplexy is rare endocrine emergency which can occur due to infarction or haemorrhage of pituitary gland. This disorder most often involves a pituitary adenoma. Occasionally it may be the first manifestation of an underlying adenoma. There is conflicting data regarding which type of pituitary adenoma is prone for apoplexy. Some studies showed predominance of non-functional adenomas while some other studies showed a higher prevalence in functioning adenomas amongst which prolactinoma have the highest risk. Although pituitary apoplexy can occur without any precipitating factor in most cases, there are some well recognizable risk factors such as hypertension, medications, major surgeries, coagulopathies either primary or following medications or infection, head injury, radiation or dynamic testing of the pituitary. Patients usually present with headache, vomiting, altered sensorium, visual defect and/or endocrine dysfunction. Hemodynamic instability may be result from adrenocorticotrophic hormone deficiency. Imaging with either CT scan or MRI should be performed in suspected cases. Intravenous fluid and hydrocortisone should be administered after collection of sample for baseline hormonal evaluation. Earlier studies used to advocate urgent decompression of the lesion but more recent studies favor conservative approach for most cases with surgery reserved for those with deteriorating level of consciousness or increasing visual defect. The visual and endocrine outcomes are almost similar with either surgery or conservative management. Once the acute phase is over, patient should be re-evaluated for hormonal deficiencies.

Keywords: Apoplexy; hypopituitarism; pituitary.

Figure 1

Blood supply to the pituitary gland. Notable features are the portal vessels which provide 70%-90% of blood supply to the anterior pituitary. While most part of the blood suplly to the adenomas are provided by inferior pituitary artery, the compression of the superior hypophyseal artery and its branches against the diaphragmasellae could lead to ischemia of the anterior pituitary and not the adenoma. (image courtesy www.pharmacology2000.com)

Figure 2

Megnetic reasonance imaging scan in pituitary apoplexy. This young lady with Cushing's Disease was found to have a macroadenoma (part A, yellow arrow, saggital view) of anterior pituitary gland during initial work up. During follow up she had resolution of her clinical symptoms after an epsode of acute severe headache. A repeat MRI scan showed partial empty sella, intact stalk (part B, yellow arrow, saggital view) (courtesy Dr. B. Kulshretha)

Figure 3

Coronal T1 (a) and axial T2 (b) showing a mass in sella with suprasellar extension having “figure of 8” appearance. Note T1 hyperintense area suggestive of bleed. The mass shows avid enhancement in post contrast coronal T1 (c) and axial T1(d) images with central nonenhancing area suggesting necrosis. (courtesy Dr. C. J. Das)

Figure 4

Empty sella as a sequel of pituitary apoplexy in a patient with Sheehan Syndrome. In this T1 weighted megnetic reasonance imaging scan (coronal) the sella turcica (yellow arrow) appers to be filled with cerebro spinal fluid, The pituitary stalk has a remarkable appearance and can be traced to the floor of sella turcica

Figure 5

Algorithm for management of pituitary apoplexy