Pituitary apoplexy
Encyclopedia
Pituitary apoplexy or pituitary tumor apoplexy is bleeding into or impaired blood supply
of the pituitary gland
at the base of the brain. This usually occurs in the presence of a tumor of the pituitary
, although in 80% of cases this has not been diagnosed previously. The most common initial symptom is a sudden headache
, often associated with a rapidly worsening visual field defect or double vision
caused by compression of nerves surrounding the gland. This is followed in many cases by acute symptoms caused by lack of secretion of essential hormones, predominantly adrenal insufficiency
.
The diagnosis is achieved with magnetic resonance imaging
and blood test
s. Treatment is by the timely correction of hormone deficiencies, and in many cases surgical decompression
is required. Many people who have had a pituitary apoplexy develop pituitary hormone deficiencies
and require long-term hormone supplementation. The first case of the disease was recorded in 1898.
and vomiting
. Occasionally, the presence of blood leads to irritation of the lining of the brain
, which may cause neck rigidity and intolerance to bright light, as well as a decreased level of consciousness. This occurs in 24% of cases.
Pressure on the part of the optic nerve
known as the chiasm
, which is located above the gland, leads to loss of vision on the outer side of the visual field on both sides
, as this corresponds to areas on the retina
s supplied by these parts of the optic nerve; it is encountered in 75% of cases. Visual acuity is reduced in half, and over 60% have a visual field defect. The visual loss depends on which part of the nerve is affected. 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.
Adjacent to the pituitary lies a part of the skull base known as the cavernous sinus
. This contains a number of nerves that control the eye muscles. 70% of people with pituitary apoplexy experience double vision due to compression of one of the nerves. 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. The oculomotor nerve is predominantly affected as it lies closest to the pituitary. The cavernous sinus also contains the carotid artery
, which supplies blood to the brain
; occasionally, compression of the artery can lead to one-sided weakness
and other symptoms of stroke
.
The pituitary gland consists of two parts, the anterior
(front) and posterior
(back) pituitary. Both parts release hormone
s 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 occurs in 70% of those with pituitary apoplexy. A sudden lack of cortisol in the body leads to a constellation of symptoms called "adrenal crisis" or "Addisonian crisis" (after a complication of Addison's disease
, the main cause of adrenal dysfunction and low cortisol levels). The main problems are low blood pressure
(particularly on standing), low blood sugars
(which can lead to coma
) and abdominal pain
; the low blood pressure can be life-threatening and requires immediate medical attention.
Hyponatremia
, an unusually low level of sodium
in the blood that may cause confusion
and seizures, is found in 40% of cases. This may be caused by low cortisol levels or by inappropriate release of antidiuretic hormone (ADH) from the posterior pituitary. Several other hormonal deficiencies may develop in the subacute phase. 50% have a deficiency in thyroid-stimulating hormone
(TSH), leading to undersecretion of thyroid hormone
by the thyroid gland and characteristic symptoms such as fatigue, weight gain, and cold intolerance. 75% develop a deficiency to gonadotropin
s (LH
and FSH
), which control the reproductive hormone glands. This leads to a disrupted menstrual cycle
, infertility
and decreased libido
.
, a benign tumor of the pituitary gland. In 80%, the patient has been previously unaware of this (although some will retrospectively report associated symptoms). It was previously thought that particular types of pituitary tumors were more prone to apoplexy than others, but this has not been confirmed. In absolute terms, only a very small proportion of pituitary tumors eventually undergoes apoplexy. In an analysis of incidentally found pituitary tumors, apoplexy occurred in 0.2% annually, but the risk was higher in tumors larger than 10 mm ("macroadenomas") and tumors that were growing more rapidly; in a meta-analysis
, not all these associations achieved statistical significance
.
The majority of cases (60–80%) are not precipitated by a particular cause. A quarter has a history of high blood pressure
, but this is a common problem in the general population, and it is not clear whether it significantly increase the risk of apoplexy. A number of cases has been reported in association with particular conditions and situations; it is uncertain whether these were in fact causative. Amongst reported assocations are surgery
(especially coronary artery bypass graft, where there are significant fluctuations in the blood pressure), disturbances in blood coagulation
or medication that inhibits coagulation
, radiation therapy
to the pituitary, traumatic brain injury
, pregnancy
(during which the pituitary enlarges) and treatment with estrogen
s. Hormonal stimulation tests of the pituitary have been reported to provoke episodes. Treatment of prolactinoma
s (pituitary adenomas that secrete prolactin
) with dopamine agonist
drugs, as well as withdrawal of such treatment, has been reported to precipitate apoplexy.
Hemorrhage from a Rathke's cleft cyst
, a remnant of Rathke's pouch
that normally regresses after embryological development, may cause symptoms that are indistinguishable from pituitary apoplexy. Pituitary apoplexy is regarded by some as distinct from Sheehan's syndrome
, where the pituitary undergoes infarction as a result of prolonged very low blood pressure, particularly when caused by bleeding after childbirth
. This condition usually occurs in the absence of a tumor. Others regard Sheehan's syndrome as a form of pituitary apoplexy.
("Turkish saddle", after its shape). 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. The pituitary gland normally derives its blood supply from vessels that pass through the hypothalamus, but tumors develop a blood supply from the nearby inferior hypophyseal artery that generates a higher blood pressure
, possibly accounting for the risk of bleeding. 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). Larger tumors are more prone to bleeding, and more rapidly growing lesions (as evidenced by detection of increased levels of the protein PCNA) may also be at a higher risk of apoplexy.
After an apoplexy, the pressure inside the sella turcica rises, and surrounding structures such as the optic nerve and the contents of the cavernous sinus are compressed. The raised pressure further impairs the blood supply to the pituitary hormone-producing tissue, leading to tissue death
due to insufficient blood supply.
(MRI) scan of the pituitary gland is performed if the diagnosis is suspected; this has a sensitivity
of over 90% for detecting pituitary apoplexy; it may demonstrate infarction
(tissue damage due to a decreased blood supply) or hemorrhage. Different MRI sequences can be used to establish when the apoplexy occurred, and the predominant form of damage (hemorrhage or infarction). If MRI is not suitable (e.g. due to claustrophobia
or the presence of metal-containing implants), a computed tomography (CT) scan may demonstrate abnormalities in the pituitary gland, although it is less reliable. Many pituitary tumors (25%) are found to have areas of hemorrhagic infarction on MRI scans, but apoplexy is not said to exist unless it is accompanied by symptoms.
In some instances, lumbar puncture
may be required if there is a suspicion that the symptoms might be caused by other problems (meningitis
or subarachnoid hemorrhage
). 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
. If there is remaining doubt about the possibility of subarachnoid hemorrhage (SAH), a magnetic resonance angiogram
(MRI with a contrast agent) may be required to identify aneurysms
of the brain blood vessels, the most common cause of SAH.
Professional guidelines recommend that if pituitary apoplexy is suspected or confirmed, the minimal blood tests performed should include a complete blood count
, urea
(a measure of renal function
, usually performed together with creatinine), electrolyte
s (sodium and potassium), liver function tests
, routine coagulation
testing, and a hormonal panel including IGF-1
, growth hormone
, prolactin
, luteinizing hormone
, follicle-stimulating hormone
, thyroid-stimulating hormone
, thyroid hormone
, and either testosterone
in men or estradiol
in women.
Visual field test
ing is recommended as soon as possible after diagnosis, as it quantifies the severity of any optic nerve involvement, and may be required to decide on surgical treatment.
. Cortisol deficiency can cause severe low blood pressure
. Depending on the severity of the illness, admission to a high dependency unit (HDU) may be required.
Treatment for acute adrenal insufficiency requires the administration of intravenous
saline
or dextrose
solution; volumes of over two liters may be required in an adult. This is followed by the administration of hydrocortisone, which is pharmaceutical grade cortisol, intravenously
or into a muscle
. The drug dexamethasone
has similar properties, but its use is not recommended unless it is required to reduce swelling in the brain
around the area of hemorrhage. Some are well enough not to require immediate cortisol replacement; in this case, blood levels of cortisol are determined at 9:00 AM (as cortisol levels vary over the day). A level below 550 nmol/l indicates a need for replacement.
The decision on whether to surgically decompress
the pituitary gland is complex and mainly dependent on the severity of visual loss and visual field defects. 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. Most commonly, operations on the pituitary gland are performed through transsphenoidal surgery
. 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
. Surgery is most likely to improve vision if there was some remaining vision before surgery, and if surgery is undertaken within a week of the onset of symptoms.
Those with relatively mild visual field loss or double vision only may be managed conservatively, with close observation of the level of consciousness, visual fields, and results of routine blood tests. If there is any deterioration, or expected spontaneous improvement does not occur, surgical intervention may still be indicated. If the apoplexy occurred in a prolactin-secreting tumor, this may respond to dopamine agonist
treatment.
After recovery, people who have had pituitary apoplexy require follow-up by an endocrinologist
to monitor for long-term consequences. MRI scans are performed 3–6 months after the initial episode and subsequently on an annual basis. If after surgery some tumor tissue remains, this may respond to medication, further surgery, or radiation therapy
with a "gamma knife
".
After an episode of pituitary apoplexy, 80% of people develop hypopituitarism
and require some form of hormone replacement therapy
. The most common problem is growth hormone deficiency
, which is often left untreated but may cause decreased muscle
mass and strength, obesity
and fatigue. 60–80% require hydrocortisone replacement (either permanently or when unwell), 50–60% need thyroid hormone replacement, and 60–80% of men require testosterone supplements. Finally, 10–25% develop diabetes insipidus
, the inability to retain fluid in the kidneys due to a lack of the pituitary antidiuretic hormone. This may be treated with the drug desmopressin
, which can be applied as a nose spray or taken by mouth.
The average age at onset is 50; cases have reported in people between 15 and 90 years old. Men are affected more commonly than women, with a male-to-female ratio of 1.6. The majority of the underlying tumors are "null cell" or nonsecretory tumors, which do not produce excessive amounts of hormones; this might explain why the tumor has often gone undetected prior to an episode of apoplexy.
in 1898. This was followed in 1905 by a further report from the German physician Bleibtreu. Surgery for pituitary apoplexy was described in 1925. Before the introduction of steroid replacement, the mortality from pituitary apoplexy approximated 50%.
The name of the condition was coined in 1950 in a case series by physicians from Boston City Hospital
and Harvard Medical School
. The term "apoplexy" was applied as it referred to both necrosis and bleeding into pituitary tumors.
Infarction
In medicine, infarction refers to tissue death that is caused by a local lack of oxygen due to obstruction of the tissue's blood supply. The resulting lesion is referred to as an infarct.-Causes:...
of the pituitary gland
Pituitary gland
In vertebrate anatomy the pituitary gland, or hypophysis, is an endocrine gland about the size of a pea and weighing 0.5 g , in humans. It is a protrusion off the bottom of the hypothalamus at the base of the brain, and rests in a small, bony cavity covered by a dural fold...
at the base of the brain. This usually occurs in the presence of a tumor of the pituitary
Pituitary adenoma
Pituitary adenomas are tumors that occur in the pituitary gland, and account for about 15% of intracranial neoplasms. Tumors which exceed 10 mm in size are defined as macroadenomas, and those smaller than 10 mm are referred to as microadenomas...
, although in 80% of cases this has not been diagnosed previously. The most common initial symptom is a sudden headache
Thunderclap headache
A thunderclap headache is a headache that is severe and sudden-onset. It is defined as a severe headache that takes seconds to minutes to reach maximum intensity. It can be indicative of a number of medical problems, most importantly subarachnoid hemorrhage, which can be potentially life-threatening...
, often associated with a rapidly worsening visual field defect or double vision
Diplopia
Diplopia, commonly known as double vision, is the simultaneous perception of two images of a single object that may be displaced horizontally, vertically, or diagonally in relation to each other...
caused by compression of nerves surrounding the gland. This is followed in many cases by acute symptoms caused by lack of secretion of essential hormones, predominantly adrenal insufficiency
Adrenal insufficiency
Adrenal insufficiency is a condition in which the adrenal glands, located above the kidneys, do not produce adequate amounts of steroid hormones , primarily cortisol, but may also include impaired aldosterone production which regulates sodium, potassium and water retention...
.
The diagnosis is achieved with magnetic resonance imaging
Magnetic resonance imaging
Magnetic resonance imaging , nuclear magnetic resonance imaging , or magnetic resonance tomography is a medical imaging technique used in radiology to visualize detailed internal structures...
and blood test
Blood test
A blood test is a laboratory analysis performed on a blood sample that is usually extracted from a vein in the arm using a needle, or via fingerprick....
s. Treatment is by the timely correction of hormone deficiencies, and in many cases surgical decompression
Hypophysectomy
Hypophysectomy is the surgical removal of the hypophysis . It is most commonly performed to treat tumors, especially craniopharyngioma tumors. Sometimes it is used to treat Cushing's syndrome due to pituitary adenoma...
is required. Many people who have had a pituitary apoplexy develop pituitary hormone deficiencies
Hypopituitarism
Hypopituitarism is the decreased secretion of one or more of the eight hormones normally produced by the pituitary gland at the base of the brain...
and require long-term hormone supplementation. The first case of the disease was recorded in 1898.
Acute symptoms
The initial symptoms of pituitary apoplexy are related to the increased pressure in and around the pituitary gland. The most common symptom, in over 95% of cases, is a sudden-onset headache located behind the eyes or around the temples. It is often associated with nauseaNausea
Nausea , is a sensation of unease and discomfort in the upper stomach with an involuntary urge to vomit. It often, but not always, precedes vomiting...
and vomiting
Vomiting
Vomiting is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose...
. Occasionally, the presence of blood leads to irritation of the lining of the brain
Meningism
Meningism is the triad of nuchal rigidity , photophobia and headache. It is a sign of irritation of the meninges, such as seen in meningitis, subarachnoid hemorrhages and various other diseases...
, which may cause neck rigidity and intolerance to bright light, as well as a decreased level of consciousness. This occurs in 24% of cases.
Pressure on the part of the optic nerve
Optic nerve
The optic nerve, also called cranial nerve 2, transmits visual information from the retina to the brain. Derived from the embryonic retinal ganglion cell, a diverticulum located in the diencephalon, the optic nerve doesn't regenerate after transection.-Anatomy:The optic nerve is the second of...
known as the chiasm
Optic chiasm
The optic chiasm or optic chiasma is the part of the brain where the optic nerves partially cross...
, which is located above the gland, leads to loss of vision on the outer side of the visual field on both sides
Bitemporal hemianopsia
Bitemporal hemianopsia is the medical description of a type of partial blindness where vision is missing in the outer half of both the right and left visual field...
, as this corresponds to areas on the retina
Retina
The vertebrate retina is a light-sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...
s supplied by these parts of the optic nerve; it is encountered in 75% of cases. Visual acuity is reduced in half, and over 60% have a visual field defect. The visual loss depends on which part of the nerve is affected. 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
Homonymous hemianopsia
Hemianopsia or hemianopia is visual field loss that respects the vertical midline, and usually affects both eyes, but can involve one eye only. Homonymous hemianopsia, or homonymous hemianopia occurs when there is hemianopic visual field loss on the same side of both eyes...
occurs.
Adjacent to the pituitary lies a part of the skull base known as the cavernous sinus
Cavernous sinus
The cavernous sinus , within the human head, is a large collection of thin-walled veins creating a cavity bordered by the temporal bone of the skull and the sphenoid bone, lateral to the sella turcica.-Contents:...
. This contains a number of nerves that control the eye muscles. 70% of people with pituitary apoplexy experience double vision due to compression of one of the nerves. In half of these cases, the oculomotor nerve
Oculomotor nerve
The oculomotor nerve is the 3rd of 12 paired cranial nerves. It enters the orbit via the superior orbital fissure and controls most of the eye's movements, including constriction of the pupil and maintaining an open eyelid by innervating the Levator palpebrae superiors muscle. The optic nerve is...
(the third cranial nerve), which controls a number of eye muscles, is affected. This leads to diagonal double vision and a dilated pupil
Mydriasis
Mydriasis is a dilation of the pupil due to disease, trauma or the use of drugs. Normally, the pupil dilates in the dark and constricts in the light to respectively improve vividity at night and to protect the retina from sunlight damage during the day...
. The fourth
Trochlear nerve
The trochlear nerve is a motor nerve that innervates a single muscle: the superior oblique muscle of the eye....
(trochlear) and sixth (abducens) cranial nerves are located in the same compartment and can cause diagonal or horizontal double vision, respectively. The oculomotor nerve is predominantly affected as it lies closest to the pituitary. The cavernous sinus also contains the carotid artery
Carotid artery
Carotid artery can refer to:* Common carotid artery* External carotid artery* Internal carotid artery...
, which supplies blood to the brain
Brain
The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...
; occasionally, compression of the artery can lead to one-sided weakness
Hemiplegia
Hemiplegia /he.mə.pliː.dʒiə/ is total paralysis of the arm, leg, and trunk on the same side of the body. Hemiplegia is more severe than hemiparesis, wherein one half of the body has less marked weakness....
and other symptoms of stroke
Stroke
A stroke, previously known medically as a cerebrovascular accident , is the rapidly developing loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischemia caused by blockage , or a hemorrhage...
.
Endocrine dysfunction
Anterior pituitary
A major organ of the endocrine system, the anterior pituitary, also called the adenohypophysis, is the glandular, anterior lobe of the pituitary gland...
(front) and posterior
Posterior pituitary
The posterior pituitary comprises the posterior lobe of the pituitary gland and is part of the endocrine system. Despite its name, the posterior pituitary gland is not a gland, per se; rather, it is largely a collection of axonal projections from the hypothalamus that terminate behind the anterior...
(back) pituitary. Both parts release hormone
Hormone
A hormone is a chemical released by a cell or a gland in one part of the body that sends out messages that affect cells in other parts of the organism. Only a small amount of hormone is required to alter cell metabolism. In essence, it is a chemical messenger that transports a signal from one...
s that control numerous other organs. In pituitary apoplexy, the main initial problem is a lack of secretion of adrenocorticotropic hormone
Adrenocorticotropic hormone
Adrenocorticotropic hormone , also known as 'corticotropin', 'Adrenocorticotrophic hormone', is a polypeptide tropic hormone produced and secreted by the anterior pituitary gland. It is an important component of the hypothalamic-pituitary-adrenal axis and is often produced in response to biological...
(ACTH, corticotropin), which stimulates the secretion of cortisol
Cortisol
Cortisol is a steroid hormone, more specifically a glucocorticoid, produced by the adrenal gland. It is released in response to stress and a low level of blood glucocorticoids. Its primary functions are to increase blood sugar through gluconeogenesis; suppress the immune system; and aid in fat,...
by the adrenal gland
Adrenal gland
In mammals, the adrenal glands are endocrine glands that sit atop the kidneys; in humans, the right suprarenal gland is triangular shaped, while the left suprarenal gland is semilunar shaped...
. This occurs in 70% of those with pituitary apoplexy. A sudden lack of cortisol in the body leads to a constellation of symptoms called "adrenal crisis" or "Addisonian crisis" (after a complication of Addison's disease
Addison's disease
Addison’s disease is a rare, chronic endocrine disorder in which the adrenal glands do not produce sufficient steroid hormones...
, the main cause of adrenal dysfunction and low cortisol levels). The main problems are low blood pressure
Hypotension
In physiology and medicine, hypotension is abnormally low blood pressure, especially in the arteries of the systemic circulation. It is best understood as a physiologic state, rather than a disease. It is often associated with shock, though not necessarily indicative of it. Hypotension is the...
(particularly on standing), low blood sugars
Hypoglycemia
Hypoglycemia or hypoglycæmia is the medical term for a state produced by a lower than normal level of blood glucose. The term literally means "under-sweet blood"...
(which can lead to coma
Coma
In medicine, a coma is a state of unconsciousness, lasting more than 6 hours in which a person cannot be awakened, fails to respond normally to painful stimuli, light or sound, lacks a normal sleep-wake cycle and does not initiate voluntary actions. A person in a state of coma is described as...
) and abdominal pain
Abdominal pain
Abdominal pain can be one of the symptoms associated with transient disorders or serious disease. Making a definitive diagnosis of the cause of abdominal pain can be difficult, because many diseases can result in this symptom. Abdominal pain is a common problem...
; the low blood pressure can be life-threatening and requires immediate medical attention.
Hyponatremia
Hyponatremia
Hyponatremia is an electrolyte disturbance in which the sodium concentration in the serum is lower than normal. In the vast majority of cases, hyponatremia occurs as a result of excess body water diluting the serum sodium and is not due to sodium deficiency. Sodium is the dominant extracellular...
, an unusually low level of sodium
Sodium
Sodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals; its only stable isotope is 23Na. It is an abundant element that exists in numerous minerals, most commonly as sodium chloride...
in the blood that may cause confusion
Mental confusion
Confusion of a pathological degree usually refers to loss of orientation sometimes accompanied by disordered consciousness and often memory Confusion (from Latin confusĭo, -ōnis, noun of action from confundere "to pour together", also "to confuse") of a pathological degree usually refers to loss...
and seizures, is found in 40% of cases. This may be caused by low cortisol levels or by inappropriate release of antidiuretic hormone (ADH) from the posterior pituitary. Several other hormonal deficiencies may develop in the subacute phase. 50% have a deficiency in thyroid-stimulating hormone
Thyroid-stimulating hormone
Thyrotrophin-stimulating hormone is a peptide hormone synthesized and secreted by thyrotrope cells in the anterior pituitary gland, which regulates the endocrine function of the thyroid gland.- Physiology :...
(TSH), leading to undersecretion of thyroid hormone
Thyroid hormone
The thyroid hormones, thyroxine and triiodothyronine , are tyrosine-based hormones produced by the thyroid gland primarily responsible for regulation of metabolism. An important component in the synthesis of thyroid hormones is iodine. The major form of thyroid hormone in the blood is thyroxine ,...
by the thyroid gland and characteristic symptoms such as fatigue, weight gain, and cold intolerance. 75% develop a deficiency to gonadotropin
Gonadotropin
Gonadotropins are protein hormones secreted by gonadotrope cells of the pituitary gland of vertebrates. This is a family of proteins, which include the mammalian hormones follitropin , lutropin , placental chorionic gonadotropins hCG and eCG and chorionic gonadotropin , as well as at least two...
s (LH
Luteinizing hormone
Luteinizing hormone is a hormone produced by the anterior pituitary gland. In females, an acute rise of LH called the LH surge triggers ovulation and development of the corpus luteum. In males, where LH had also been called interstitial cell-stimulating hormone , it stimulates Leydig cell...
and FSH
Follicle-stimulating hormone
Follicle-stimulating hormone is a hormone found in humans and other animals. It is synthesized and secreted by gonadotrophs of the anterior pituitary gland. FSH regulates the development, growth, pubertal maturation, and reproductive processes of the body. FSH and Luteinizing hormone act...
), which control the reproductive hormone glands. This leads to a disrupted menstrual cycle
Menstrual cycle
The menstrual cycle is the scientific term for the physiological changes that can occur in fertile women for the purpose of sexual reproduction. This article focuses on the human menstrual cycle....
, infertility
Infertility
Infertility primarily refers to the biological inability of a person to contribute to conception. Infertility may also refer to the state of a woman who is unable to carry a pregnancy to full term...
and decreased libido
Libido
Libido refers to a person's sex drive or desire for sexual activity. The desire for sex is an aspect of a person's sexuality, but varies enormously from one person to another, and it also varies depending on circumstances at a particular time. A person who has extremely frequent or a suddenly...
.
Causes
Almost all cases of pituitary apoplexy arise from a pituitary adenomaPituitary adenoma
Pituitary adenomas are tumors that occur in the pituitary gland, and account for about 15% of intracranial neoplasms. Tumors which exceed 10 mm in size are defined as macroadenomas, and those smaller than 10 mm are referred to as microadenomas...
, a benign tumor of the pituitary gland. In 80%, the patient has been previously unaware of this (although some will retrospectively report associated symptoms). It was previously thought that particular types of pituitary tumors were more prone to apoplexy than others, but this has not been confirmed. In absolute terms, only a very small proportion of pituitary tumors eventually undergoes apoplexy. In an analysis of incidentally found pituitary tumors, apoplexy occurred in 0.2% annually, but the risk was higher in tumors larger than 10 mm ("macroadenomas") and tumors that were growing more rapidly; in a meta-analysis
Meta-analysis
In statistics, a meta-analysis combines the results of several studies that address a set of related research hypotheses. In its simplest form, this is normally by identification of a common measure of effect size, for which a weighted average might be the output of a meta-analyses. Here the...
, not all these associations achieved statistical significance
Statistical significance
In statistics, a result is called statistically significant if it is unlikely to have occurred by chance. The phrase test of significance was coined by Ronald Fisher....
.
The majority of cases (60–80%) are not precipitated by a particular cause. A quarter has a history of high blood pressure
Hypertension
Hypertension or high blood pressure is a cardiac chronic medical condition in which the systemic arterial blood pressure is elevated. What that means is that the heart is having to work harder than it should to pump the blood around the body. Blood pressure involves two measurements, systolic and...
, but this is a common problem in the general population, and it is not clear whether it significantly increase the risk of apoplexy. A number of cases has been reported in association with particular conditions and situations; it is uncertain whether these were in fact causative. Amongst reported assocations are surgery
Surgery
Surgery is an ancient medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, or to help improve bodily function or appearance.An act of performing surgery may be called a surgical...
(especially coronary artery bypass graft, where there are significant fluctuations in the blood pressure), disturbances in blood coagulation
Coagulopathy
Coagulopathy is a condition in which the blood’s ability to clot is impaired. This condition can cause prolonged or excessive bleeding, which may occur spontaneously or following an injury or medical and dental procedures.The normal clotting process depends on the interplay of various proteins in...
or medication that inhibits coagulation
Anticoagulant
An anticoagulant is a substance that prevents coagulation of blood. A group of pharmaceuticals called anticoagulants can be used in vivo as a medication for thrombotic disorders. Some anticoagulants are used in medical equipment, such as test tubes, blood transfusion bags, and renal dialysis...
, radiation therapy
Radiation therapy
Radiation therapy , radiation oncology, or radiotherapy , sometimes abbreviated to XRT or DXT, is the medical use of ionizing radiation, generally as part of cancer treatment to control malignant cells.Radiation therapy is commonly applied to the cancerous tumor because of its ability to control...
to the pituitary, traumatic brain injury
Traumatic brain injury
Traumatic brain injury , also known as intracranial injury, occurs when an external force traumatically injures the brain. TBI can be classified based on severity, mechanism , or other features...
, pregnancy
Pregnancy
Pregnancy refers to the fertilization and development of one or more offspring, known as a fetus or embryo, in a woman's uterus. In a pregnancy, there can be multiple gestations, as in the case of twins or triplets...
(during which the pituitary enlarges) and treatment with estrogen
Estrogen
Estrogens , oestrogens , or œstrogens, are a group of compounds named for their importance in the estrous cycle of humans and other animals. They are the primary female sex hormones. Natural estrogens are steroid hormones, while some synthetic ones are non-steroidal...
s. Hormonal stimulation tests of the pituitary have been reported to provoke episodes. Treatment of prolactinoma
Prolactinoma
A prolactinoma is a benign tumor of the pituitary gland that produces a hormone called prolactin. It is the most common type of pituitary tumor...
s (pituitary adenomas that secrete prolactin
Prolactin
Prolactin also known as luteotropic hormone is a protein that in humans is encoded by the PRL gene.Prolactin is a peptide hormone discovered by Henry Friesen...
) with dopamine agonist
Dopamine agonist
A dopamine agonist is a compound that activates dopamine receptors in the absence of dopamine. Dopamine agonists activate signaling pathways through the dopamine receptor and trimeric G-proteins, ultimately leading to changes in gene transcription.-Uses:...
drugs, as well as withdrawal of such treatment, has been reported to precipitate apoplexy.
Hemorrhage from a Rathke's cleft cyst
Rathke's cleft cyst
A Rathke's cleft cyst is a benign growth found on the pituitary gland in the brain, specifically a fluid-filled cyst in the posterior portion of the anterior pituitary gland...
, a remnant of Rathke's pouch
Rathke's pouch
In embryogenesis, Rathke's pouch is a depression in the roof of the developing mouth in front of the buccopharyngeal membrane. It gives rise to the anterior pituitary , a part of the endocrine system.-Development:...
that normally regresses after embryological development, may cause symptoms that are indistinguishable from pituitary apoplexy. Pituitary apoplexy is regarded by some as distinct from Sheehan's syndrome
Sheehan's syndrome
Sheehan syndrome, also known as Simmonds' syndrome or postpartum hypopituitarism or postpartum pituitary necrosis, is hypopituitarism , caused by necrosis due to blood loss and hypovolemic shock during and after childbirth...
, where the pituitary undergoes infarction as a result of prolonged very low blood pressure, particularly when caused by bleeding after childbirth
Postpartum hemorrhage
Hemorrhage after delivery, or postpartum hemorrhage, is the loss of greater than 500 ml of blood following vaginal delivery, or 1000 ml of blood following cesarean section...
. This condition usually occurs in the absence of a tumor. Others regard Sheehan's syndrome as a form of pituitary apoplexy.
Mechanism
The pituitary gland is located in a recess in the skull base known as the sella turcicaSella turcica
-External links:*...
("Turkish saddle", after its shape). It is attached to the hypothalamus
Hypothalamus
The Hypothalamus is a portion of the brain that contains a number of small nuclei with a variety of functions...
, 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. The pituitary gland normally derives its blood supply from vessels that pass through the hypothalamus, but tumors develop a blood supply from the nearby inferior hypophyseal artery that generates a higher blood pressure
Blood pressure
Blood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...
, possibly accounting for the risk of bleeding. 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). Larger tumors are more prone to bleeding, and more rapidly growing lesions (as evidenced by detection of increased levels of the protein PCNA) may also be at a higher risk of apoplexy.
After an apoplexy, the pressure inside the sella turcica rises, and surrounding structures such as the optic nerve and the contents of the cavernous sinus are compressed. The raised pressure further impairs the blood supply to the pituitary hormone-producing tissue, leading to tissue death
Necrosis
Necrosis is the premature death of cells in living tissue. Necrosis is caused by factors external to the cell or tissue, such as infection, toxins, or trauma. This is in contrast to apoptosis, which is a naturally occurring cause of cellular death...
due to insufficient blood supply.
Diagnosis
It is recommended that magnetic resonance imagingMagnetic resonance imaging
Magnetic resonance imaging , nuclear magnetic resonance imaging , or magnetic resonance tomography is a medical imaging technique used in radiology to visualize detailed internal structures...
(MRI) scan of the pituitary gland is performed if the diagnosis is suspected; this has a sensitivity
Sensitivity and specificity
Sensitivity and specificity are statistical measures of the performance of a binary classification test, also known in statistics as classification function. Sensitivity measures the proportion of actual positives which are correctly identified as such Sensitivity and specificity are statistical...
of over 90% for detecting pituitary apoplexy; it may demonstrate infarction
Infarction
In medicine, infarction refers to tissue death that is caused by a local lack of oxygen due to obstruction of the tissue's blood supply. The resulting lesion is referred to as an infarct.-Causes:...
(tissue damage due to a decreased blood supply) or hemorrhage. Different MRI sequences can be used to establish when the apoplexy occurred, and the predominant form of damage (hemorrhage or infarction). If MRI is not suitable (e.g. due to claustrophobia
Claustrophobia
Claustrophobia is the fear of having no escape and being closed in small spaces or rooms...
or the presence of metal-containing implants), a computed tomography (CT) scan may demonstrate abnormalities in the pituitary gland, although it is less reliable. Many pituitary tumors (25%) are found to have areas of hemorrhagic infarction on MRI scans, but apoplexy is not said to exist unless it is accompanied by symptoms.
In some instances, lumbar puncture
Lumbar puncture
A lumbar puncture is a diagnostic and at times therapeutic procedure that is performed in order to collect a sample of cerebrospinal fluid for biochemical, microbiological, and cytological analysis, or very rarely as a treatment to relieve increased intracranial pressure.-Indications:The...
may be required if there is a suspicion that the symptoms might be caused by other problems (meningitis
Meningitis
Meningitis is inflammation of the protective membranes covering the brain and spinal cord, known collectively as the meninges. The inflammation may be caused by infection with viruses, bacteria, or other microorganisms, and less commonly by certain drugs...
or subarachnoid hemorrhage
Subarachnoid hemorrhage
A subarachnoid hemorrhage , or subarachnoid haemorrhage in British English, is bleeding into the subarachnoid space—the area between the arachnoid membrane and the pia mater surrounding the brain...
). This is the examination of the cerebrospinal fluid
Cerebrospinal fluid
Cerebrospinal fluid , Liquor cerebrospinalis, is a clear, colorless, bodily fluid, that occupies the subarachnoid space and the ventricular system around and inside the brain and spinal cord...
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
Subarachnoid space
In the central nervous system, the subarachnoid cavity is the interval between the arachnoid membrane and pia mater....
. If there is remaining doubt about the possibility of subarachnoid hemorrhage (SAH), a magnetic resonance angiogram
Magnetic Resonance Angiography
Magnetic resonance angiography is a group of techniques based on Magnetic Resonance Imaging to image blood vessels. Magnetic resonance angiography is used to generate images of the arteries in order to evaluate them for stenosis , occlusion or aneurysms...
(MRI with a contrast agent) may be required to identify aneurysms
Cerebral aneurysm
A cerebral or brain aneurysm is a cerebrovascular disorder in which weakness in the wall of a cerebral artery or vein causes a localized dilation or ballooning of the blood vessel.- Signs and symptoms :...
of the brain blood vessels, the most common cause of SAH.
Professional guidelines recommend that if pituitary apoplexy is suspected or confirmed, the minimal blood tests performed should include a complete blood count
Complete blood count
A complete blood count , also known as full blood count or full blood exam or blood panel, is a test panel requested by a doctor or other medical professional that gives information about the cells in a patient's blood...
, urea
Urea
Urea or carbamide is an organic compound with the chemical formula CO2. The molecule has two —NH2 groups joined by a carbonyl functional group....
(a measure of renal function
Renal function
Renal function, in nephrology, is an indication of the state of the kidney and its role in renal physiology. Glomerular filtration rate describes the flow rate of filtered fluid through the kidney...
, usually performed together with creatinine), electrolyte
Electrolyte
In chemistry, an electrolyte is any substance containing free ions that make the substance electrically conductive. The most typical electrolyte is an ionic solution, but molten electrolytes and solid electrolytes are also possible....
s (sodium and potassium), liver function tests
Liver function tests
Liver function tests , are groups of clinical biochemistry laboratory blood assays designed to give information about the state of a patient's liver. The parameters measured include PT/INR, aPTT, albumin, billirubin and others...
, routine coagulation
Coagulation
Coagulation is a complex process by which blood forms clots. It is an important part of hemostasis, the cessation of blood loss from a damaged vessel, wherein a damaged blood vessel wall is covered by a platelet and fibrin-containing clot to stop bleeding and begin repair of the damaged vessel...
testing, and a hormonal panel including IGF-1
Insulin-like growth factor 1
Insulin-like growth factor 1 also known as somatomedin C is a protein that in humans is encoded by the IGF1 gene. IGF-1 has also been referred to as a "sulfation factor" and its effects were termed "nonsuppressible insulin-like activity" in the 1970s.IGF-1 is a hormone similar in molecular...
, growth hormone
Growth hormone
Growth hormone is a peptide hormone that stimulates growth, cell reproduction and regeneration in humans and other animals. Growth hormone is a 191-amino acid, single-chain polypeptide that is synthesized, stored, and secreted by the somatotroph cells within the lateral wings of the anterior...
, prolactin
Prolactin
Prolactin also known as luteotropic hormone is a protein that in humans is encoded by the PRL gene.Prolactin is a peptide hormone discovered by Henry Friesen...
, luteinizing hormone
Luteinizing hormone
Luteinizing hormone is a hormone produced by the anterior pituitary gland. In females, an acute rise of LH called the LH surge triggers ovulation and development of the corpus luteum. In males, where LH had also been called interstitial cell-stimulating hormone , it stimulates Leydig cell...
, follicle-stimulating hormone
Follicle-stimulating hormone
Follicle-stimulating hormone is a hormone found in humans and other animals. It is synthesized and secreted by gonadotrophs of the anterior pituitary gland. FSH regulates the development, growth, pubertal maturation, and reproductive processes of the body. FSH and Luteinizing hormone act...
, thyroid-stimulating hormone
Thyroid-stimulating hormone
Thyrotrophin-stimulating hormone is a peptide hormone synthesized and secreted by thyrotrope cells in the anterior pituitary gland, which regulates the endocrine function of the thyroid gland.- Physiology :...
, thyroid hormone
Thyroxine
Thyroxine, or 3,5,3',5'-tetraiodothyronine , a form of thyroid hormones, is the major hormone secreted by the follicular cells of the thyroid gland.-Synthesis and regulation:...
, and either testosterone
Testosterone
Testosterone is a steroid hormone from the androgen group and is found in mammals, reptiles, birds, and other vertebrates. In mammals, testosterone is primarily secreted in the testes of males and the ovaries of females, although small amounts are also secreted by the adrenal glands...
in men or estradiol
Estradiol
Estradiol is a sex hormone. Estradiol is abbreviated E2 as it has 2 hydroxyl groups in its molecular structure. Estrone has 1 and estriol has 3 . Estradiol is about 10 times as potent as estrone and about 80 times as potent as estriol in its estrogenic effect...
in women.
Visual field test
Visual field test
A visual field test is an examination that may be performed to analyze a patient's visual field. The exam may be performed by a technician in one of several ways. The test may be performed by a technician directly, with the assistance of a machine, or completely by an automated machine...
ing is recommended as soon as possible after diagnosis, as it quantifies the severity of any optic nerve involvement, and may be required to decide on surgical treatment.
Treatment
The first priority in suspected or confirmed pituitary apoplexy is stabilization of the circulatory systemCirculatory system
The circulatory system is an organ system that passes nutrients , gases, hormones, blood cells, etc...
. Cortisol deficiency can cause severe low blood pressure
Hypotension
In physiology and medicine, hypotension is abnormally low blood pressure, especially in the arteries of the systemic circulation. It is best understood as a physiologic state, rather than a disease. It is often associated with shock, though not necessarily indicative of it. Hypotension is the...
. Depending on the severity of the illness, admission to a high dependency unit (HDU) may be required.
Treatment for acute adrenal insufficiency requires the administration of intravenous
Intravenous therapy
Intravenous therapy or IV therapy is the infusion of liquid substances directly into a vein. The word intravenous simply means "within a vein". Therapies administered intravenously are often called specialty pharmaceuticals...
saline
Saline (medicine)
In medicine, saline is a general term referring to a sterile solution of sodium chloride in water but is only sterile when it is to be placed intravenously, otherwise, a saline solution is a salt water solution...
or dextrose
Glucose
Glucose is a simple sugar and an important carbohydrate in biology. Cells use it as the primary source of energy and a metabolic intermediate...
solution; volumes of over two liters may be required in an adult. This is followed by the administration of hydrocortisone, which is pharmaceutical grade cortisol, intravenously
Intravenous therapy
Intravenous therapy or IV therapy is the infusion of liquid substances directly into a vein. The word intravenous simply means "within a vein". Therapies administered intravenously are often called specialty pharmaceuticals...
or into a muscle
Intramuscular injection
Intramuscular injection is the injection of a substance directly into a muscle. In medicine, it is one of several alternative methods for the administration of medications . It is used for particular forms of medication that are administered in small amounts...
. The drug dexamethasone
Dexamethasone
Dexamethasone is a potent synthetic member of the glucocorticoid class of steroid drugs. It acts as an anti-inflammatory and immunosuppressant...
has similar properties, but its use is not recommended unless it is required to reduce swelling in the brain
Cerebral edema
Cerebral edema or cerebral œdema is an excess accumulation of water in the intracellular or extracellular spaces of the brain.-Vasogenic:Due to a breakdown of tight endothelial junctions which make up the blood-brain barrier...
around the area of hemorrhage. Some are well enough not to require immediate cortisol replacement; in this case, blood levels of cortisol are determined at 9:00 AM (as cortisol levels vary over the day). A level below 550 nmol/l indicates a need for replacement.
The decision on whether to surgically decompress
Hypophysectomy
Hypophysectomy is the surgical removal of the hypophysis . It is most commonly performed to treat tumors, especially craniopharyngioma tumors. Sometimes it is used to treat Cushing's syndrome due to pituitary adenoma...
the pituitary gland is complex and mainly dependent on the severity of visual loss and visual field defects. If visual acuity
Visual acuity
Visual acuity is acuteness or clearness of vision, which is dependent on the sharpness of the retinal focus within the eye and the sensitivity of the interpretative faculty of the brain....
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. Most commonly, operations on the pituitary gland are performed through transsphenoidal surgery
Transsphenoidal surgery
Transsphenoidal surgery is a type of surgery in which surgical instruments are inserted into part of the brain by going through the nose and the sphenoid bone . Transsphenoidal surgery is used to remove tumors of the pituitary gland.- External links :* entry in the public domain NCI Dictionary of...
. In this procedure, surgical instruments are passed through the nose
Nose
Anatomically, a nose is a protuberance in vertebrates that houses the nostrils, or nares, which admit and expel air for respiration in conjunction with the mouth. Behind the nose are the olfactory mucosa and the sinuses. Behind the nasal cavity, air next passes through the pharynx, shared with the...
towards the sphenoid bone
Sphenoid bone
The sphenoid bone is an unpaired bone situated at the base of the skull in front of the temporal bone and basilar part of the occipital bone.The sphenoid bone is one of the seven bones that articulate to form the orbit...
, which is opened to give access to the cavity that contains the pituitary gland
Sella turcica
-External links:*...
. Surgery is most likely to improve vision if there was some remaining vision before surgery, and if surgery is undertaken within a week of the onset of symptoms.
Those with relatively mild visual field loss or double vision only may be managed conservatively, with close observation of the level of consciousness, visual fields, and results of routine blood tests. If there is any deterioration, or expected spontaneous improvement does not occur, surgical intervention may still be indicated. If the apoplexy occurred in a prolactin-secreting tumor, this may respond to dopamine agonist
Dopamine agonist
A dopamine agonist is a compound that activates dopamine receptors in the absence of dopamine. Dopamine agonists activate signaling pathways through the dopamine receptor and trimeric G-proteins, ultimately leading to changes in gene transcription.-Uses:...
treatment.
After recovery, people who have had pituitary apoplexy require follow-up by an endocrinologist
Endocrinology
Endocrinology is a branch of biology and medicine dealing with the endocrine system, its diseases, and its specific secretions called hormones, the integration of developmental events such as proliferation, growth, and differentiation and the coordination of...
to monitor for long-term consequences. MRI scans are performed 3–6 months after the initial episode and subsequently on an annual basis. If after surgery some tumor tissue remains, this may respond to medication, further surgery, or radiation therapy
Radiation therapy
Radiation therapy , radiation oncology, or radiotherapy , sometimes abbreviated to XRT or DXT, is the medical use of ionizing radiation, generally as part of cancer treatment to control malignant cells.Radiation therapy is commonly applied to the cancerous tumor because of its ability to control...
with a "gamma knife
Radiosurgery
Radiosurgery is a medical procedure that allows non-invasive treatment of benign and malignant tumors. It is also known as stereotactic radiotherapy, when used to target lesions in the brain, and stereotactic body radiotherapy when used to target lesions in the body...
".
Prognosis
In larger case series, the mortality was 1.6% overall. In the group of patients who were unwell enough to require surgery, the mortality was 1.9%, with no deaths in those who could be treated conservatively.After an episode of pituitary apoplexy, 80% of people develop hypopituitarism
Hypopituitarism
Hypopituitarism is the decreased secretion of one or more of the eight hormones normally produced by the pituitary gland at the base of the brain...
and require some form of hormone replacement therapy
Hormone therapy
Hormone therapy, or hormonal therapy is the use of hormones in medical treatment. Treatment with hormone antagonists may also referred to as hormonal therapy...
. The most common problem is growth hormone deficiency
Growth hormone deficiency
Growth hormone deficiency is a medical condition in which the body does not produce enough growth hormone . Growth hormone, also called somatotropin, is a polypeptide hormone which stimulates growth and cell reproduction...
, which is often left untreated but may cause decreased muscle
Muscle
Muscle is a contractile tissue of animals and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...
mass and strength, obesity
Obesity
Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health, leading to reduced life expectancy and/or increased health problems...
and fatigue. 60–80% require hydrocortisone replacement (either permanently or when unwell), 50–60% need thyroid hormone replacement, and 60–80% of men require testosterone supplements. Finally, 10–25% develop diabetes insipidus
Diabetes insipidus
Diabetes insipidus is a condition characterized by excessive thirst and excretion of large amounts of severely diluted urine, with reduction of fluid intake having no effect on the concentration of the urine. There are several different types of DI, each with a different cause...
, the inability to retain fluid in the kidneys due to a lack of the pituitary antidiuretic hormone. This may be treated with the drug desmopressin
Desmopressin
Desmopressin is a synthetic replacement for vasopressin, the hormone that reduces urine production. It may be taken nasally, intravenously, or as a tablet...
, which can be applied as a nose spray or taken by mouth.
Epidemiology
Pituitary apoplexy is rare. Even in people with a known pituitary tumor, only 0.6–10% experience apoplexy; the risk is higher in larger tumors. Based on extrapolations from existing data, one would expect 18 cases of pituitary apoplexy per one million people every year; the actual figure is probably lower.The average age at onset is 50; cases have reported in people between 15 and 90 years old. Men are affected more commonly than women, with a male-to-female ratio of 1.6. The majority of the underlying tumors are "null cell" or nonsecretory tumors, which do not produce excessive amounts of hormones; this might explain why the tumor has often gone undetected prior to an episode of apoplexy.
History
The first case description of pituitary apoplexy has been attributed to the American neurologist Pearce BaileyPearce Bailey (neurologist)
Dr. Pierce Bailey was an American neurologist and psychiatrist, educated at Princeton and Columbia Universities. He became a consultant in several New York hospitals and with Collins and Frankel founded the Neurological Institute. He was also appointed an associate professor of neurology in Columbia...
in 1898. This was followed in 1905 by a further report from the German physician Bleibtreu. Surgery for pituitary apoplexy was described in 1925. Before the introduction of steroid replacement, the mortality from pituitary apoplexy approximated 50%.
The name of the condition was coined in 1950 in a case series by physicians from Boston City Hospital
Boston City Hospital
The Boston City Hospital in Boston, Massachusetts, was "intended for the use and comfort of poor patients, to whom medical care will be provided at the expense of the city, and .....
and Harvard Medical School
Harvard Medical School
Harvard Medical School is the graduate medical school of Harvard University. It is located in the Longwood Medical Area of the Mission Hill neighborhood of Boston, Massachusetts....
. The term "apoplexy" was applied as it referred to both necrosis and bleeding into pituitary tumors.