Acute symptoms[ edit ] The initial symptoms of pituitary apoplexy are related to the increased pressure in and around the pituitary gland. It is often associated with nausea and vomiting. If the part of the nerve between the eye and the chiasm is compressed, the result is vision loss in one eye. If the part after the chiasm is affected, visual loss on one side of the visual field occurs. This contains a number of nerves that control the eye muscles. In half of these cases, the oculomotor nerve the third cranial nerve , which controls a number of eye muscles, is affected.
|Published (Last):||7 October 2006|
|PDF File Size:||15.12 Mb|
|ePub File Size:||7.4 Mb|
|Price:||Free* [*Free Regsitration Required]|
Acute symptoms[ edit ] The initial symptoms of pituitary apoplexy are related to the increased pressure in and around the pituitary gland. It is often associated with nausea and vomiting. If the part of the nerve between the eye and the chiasm is compressed, the result is vision loss in one eye. If the part after the chiasm is affected, visual loss on one side of the visual field occurs.
This contains a number of nerves that control the eye muscles. In half of these cases, the oculomotor nerve the third cranial nerve , which controls a number of eye muscles, is affected. This leads to diagonal double vision and a dilated pupil. The fourth trochlear and sixth abducens cranial nerves are located in the same compartment and can cause diagonal or horizontal double vision, respectively.
When the stimulating hormone ACTH is not secreted, the adrenals cease to produce cortisol. The pituitary gland consists of two parts, the anterior front and posterior back pituitary. Both parts release hormones that control numerous other organs.
In pituitary apoplexy, the main initial problem is a lack of secretion of adrenocorticotropic hormone ACTH, corticotropin , which stimulates the secretion of cortisol by the adrenal gland.
This may be caused by low cortisol levels or by inappropriate release of antidiuretic hormone ADH from the posterior pituitary. This leads to a disrupted menstrual cycle , infertility , and decreased libido. In an analysis of incidentally found pituitary tumors, apoplexy occurred in 0. Hormonal stimulation tests of the pituitary have been reported to provoke episodes.
Treatment of prolactinomas pituitary adenomas that secrete prolactin with dopamine agonist drugs, as well as withdrawal of such treatment, has been reported to precipitate apoplexy. This condition usually occurs in the absence of a tumor. It is attached to the hypothalamus , a part of the brain, by a stalk that also contains the blood vessels that supply the gland. It is unclear why pituitary tumors are five times more likely to bleed than other tumors in the brain.
There are various proposed mechanisms by which a tumor can increase the risk of either infarction insufficient blood supply leading to tissue dysfunction or hemorrhage. Tumors may also be more sensitive to fluctuations in blood pressure, and the blood vessels may show structural abnormalities that make them vulnerable to damage.
It has been suggested that infarction alone causes milder symptoms than either hemorrhage or hemorrhagic infarction infarction followed by hemorrhage into the damaged tissue. The raised pressure further impairs the blood supply to the pituitary hormone-producing tissue, leading to tissue death due to insufficient blood supply.
The arrow points at the posterior pituitary intense signal , and the arrowhead at the anterior pituitary. This is the examination of the cerebrospinal fluid that envelops the brain and the spinal cord; the sample is obtained with a needle that is passed under local anesthetic into the spine.
In pituitary apoplexy the results are typically normal, although abnormalities may be detected if blood from the pituitary has entered the subarachnoid space.
Cortisol deficiency can cause severe low blood pressure. If visual acuity is severely reduced, there are large or worsening visual field defects, or the level of consciousness falls consistently, professional guidelines recommend that surgery is performed. In this procedure, surgical instruments are passed through the nose towards the sphenoid bone , which is opened to give access to the cavity that contains the pituitary gland.
If there is any deterioration, or expected spontaneous improvement does not occur, surgical intervention may still be indicated. In the group of patients who were unwell enough to require surgery, the mortality was 1. This may be treated with the drug desmopressin ,  which can be applied as a nose spray or taken by mouth.
Jan Clin Endocrinol.
Mezihn It applies only to symptomatic cases. In conclusion, even without a known history of pituitary adenoma or an abrupt onset of the clinical symptoms, the diagnosis of pituitary apoplfxie should apoplexje considered in a patient with a suprasellar mass hyperintensity in T1-weighted MR images, which may mimic craniopharyngioma. Two classifications Knosp, Cottier are in current use but invasion is still hard to say except in cases of encircled cavernous internal carotid artery Figure 8. Toussaint bD. Conclusions point to the diagnostic difficulties and the urgency of treatment in this clincal setting.