It is important to note that pituitary apoplexy may be divided into hemorrhagic or ischemic, each with unique neuroimaging findings.
The very low incidence of this complication hinders formulation of widespread guidelines on diagnostic and therapeutic management 1).
This condition results in an estimated 1.5-27.7% of cases of pituitary adenoma, although the figure is probably closer to 10%.
Mohr and Hardy reviewed hospital records of 664 patients who had surgery for pituitary adenomas 2).
They noted typical symptomatic pituitary apoplexy to occur in only 0.6% of patients with significant hemorrhagic and necrotic changes in 9.5% of surgical specimens.
Frequency of intratumoral hemorrhage increases to 26% if using only MRI criteria without clinical evidence of apoplexy. However, hemorrhagic pituitary apoplexy may be fatal. Kurisu et al reported a 68-year-old man who developed pituitary apoplexy resulting in massive intracerebral hemorrhage and death 1 month later 3)
The male-to-female predominance is 2:1.
The age range is 37-57 years.
Male sex, non-functioning tumor, and macroadenoma are associated with an increased risk 4).
This condition stems from an acute expansion of a pituitary adenoma or, less commonly, in a nonadenomatous gland, from infarction or hemorrhage. The anterior pituitary gland is perfused by its portal venous system, which passes down the hypophyseal stalk. This unusual vascular supply likely contributes to frequency of pituitary apoplexy.
Some postulate that a gradual enlarging pituitary tumor becomes impacted at the diaphragmatic notch, compressing and distorting the hypophyseal stalk and its vascular supply. This deprives the anterior pituitary gland and the tumor itself of its vascular supply, apoplectically causing ischemia and subsequent necrosis.
Another theory stipulates that rapid expansion of the tumor outstrips its vascular supply, resulting in ischemia and necrosis. This explanation is doubtful, since most tumors that undergo apoplexy are slow growing.
Cerebral ischemia due to pituitary apoplexy is very rare. It may be caused by vasospasm or direct compression of cerebral vessels by the tumor.
The clinical presentation varies widely and includes asymptomatic cases, classical pituitary apoplexy and even sudden death.
An existing pituitary adenoma is usually present. The visual symptoms may include both visual acuity impairment and visual field impairment from involvement of the optic nerve or chiasm and ocular motility dysfunction from involvement of the cranial nerves traversing the cavernous sinus 5)
Paschou et al present a patient in his late 30s presented with sudden and severe frontal headache, fever, blurred vision, nausea, confusion, as well as oculomotor nerve palsy (CN III) with partial ptosis of the left eyelid, dilated left pupil and left eye globe deviation inferiorly and laterally. The final diagnosis was acute pituitary apoplexy complicating a pituitary macroadenoma. In this setting, headache is usually present due to stretching and irritation of the dura mater, and fever due to meningeal irritation or upward expansion leading to hypothalamic dysfunction. Decreased visual acuity and defects in visual fields are caused by upward expansion, which compresses the optic chiasm. Ophthalmoplegia can also be observed due to lateral expansion with invasion of the cavernous sinus 6).
A 41-year-old woman was admitted to our neurosurgical department with a sudden-onset bursting headache and visual impairment. On admission, her vision was decreased to finger counting at 30 cm in the left eye and 50 cm in the right eye, and a severe bitemporal hemianopsia was demonstrated on visual field testing. A brain computed tomography scan revealed a subarachnoid hemorrhage at the basal cistern, and conventional cerebral catheter angiography of the left internal carotid artery demonstrated an 18×8 mm dumbbell-shaped aneurysm at the ACoA. Microscopic aneurysmal clipping was performed. An ACoA aneurysm can produce visual field defects by compressing the optic chiasm or nerves.
A 52-year-old woman, previously diagnosed with asymptomatic Rathke cleft cyst (RCC), came with a severe headache, along with visual dysfunction and symptoms of pituitary insufficiency. Fluid-attenuated inversion recovery magnetic resonance imaging demonstrated diffuse hyperintensity in the cerebral cisterns, whereas watery clear cerebrospinal fluid was obtained by lumbar puncture. Surgery performed 1 month after onset revealed a nonhemorrhagic lesion, with a final diagnosis of nonhemorrhagic RCC rupture.
Yokota et al., conclude that nonhemorrhagic RCC rupture and subsequent leakage of the contents into subarachnoid space were the underlying pathogenesis in the present case of RCC resembling apoplexy 8).
Its optimal management remains controversial. The aim of a study was to compare the outcomes of surgical and non-surgical treatments for pituitary apoplexy.
A systematic literature search was performed of MedLine, EmBase, the Cochrane Library, and the Web of Science for articles published between January 1992 and September 2014. Studies of the outcomes in consecutive patients that compared surgical intervention with non-surgical treatment for pituitary apoplexy were included.
Six studies met the inclusion criteria. As compared to the non-surgically treated patients, surgically treated patients had a significantly higher rate of recovery of ocular palsy and visual field (both P<0.05). However, there was no significant difference in the recovery of visual acuity and pituitary function (P>0.05) between the two groups.
The findings of this study suggest that surgical intervention should be advocated for pituitary apoplexy patients with visual field defects and ocular palsy 9).
Pituitary Apoplexy Presenting as Status Migrainosus 10).
A 45-year-old man who suffered an attack of pituitary apoplexy while being treated for dengue hemorrhagic fever (DHF). The issues pertaining to the management of hydrocephalus, timing of surgical intervention, and treatment of electrolyte imbalances encountered in the dual setting of DHF and pituitary apoplexy are discussed with reference to the outcome in this case.
Although patients suffering from DHF harbor multiple factors, which may be precipitants of pituitary apoplexy, the association between these two conditions is rare and only few case reports document their coexistence 11).
A case of a 40-year-old male patient who presented with headache and sudden visual loss for 3 days. He was diagnosed with pituitary apoplexy and had transnasal-transsphenoidal resection. Three days later, he achieved a complete recovery of his vision.
This report is an addition to several studies that favor early surgical decompression of pituitary fossa for apoplexy cases with severe neuro-ophthalmologic involvement. There is an increasing trend for early surgical intervention for pituitary apoplexy in the literature, especially for severe visual deterioration.
The visual outcome appears to be better in early intervention as compared to late. Nevertheless, good visual recovery is also seen in late surgical intervention 12).
A patient in his late 30s presented with sudden and severe frontal headache, fever, blurred vision, nausea, confusion, as well as oculomotor palsy (CN III) with partial ptosis of the left eyelid, dilated left pupil and left eye globe deviation inferiorly and laterally. The final diagnosis was acute pituitary apoplexy complicating a pituitary macroadenoma. In this setting, headache is usually present due to stretching and irritation of the dura mater, and fever due to meningeal irritation or upward expansion leading to hypothalamic dysfunction. Decreased visual acuity and defects in visual fields are caused by upward expansion, which compresses the optic chiasm. Ophthalmoplegia can also be observed due to lateral expansion with invasion of the cavernous sinus 13).
Rais et al., report the case of an older lady who was admitted to a tertiary teaching hospital with sub-acute functional decline of two months' duration, which was initially attributed to a concomitant urinary tract infection. Further investigations, however, revealed the diagnosis of pituitary apoplexy with central hypocortisolism. Subsequent treatment with physiological doses of steroids improved patient's function and overall well-being. This report adds to the sparse literature on pituitary apoplexy in the older adults and emphasizes the non-specific presentation of this clinical syndrome 14).
Pituitary apoplexy causing clival and spinal haematoma 15).
A case of pituitary apoplexy associated with cerebral infarction 16).
Akakın et al. describe the first case of PA following posterior lumbar fusion surgery performed while the patient was prone. In patients with a preexisting pituitary adenoma, thorough clinical and laboratory investigations should be conducted using an interdisciplinary approach before any planned surgery. In unknown cases of pituitary adenoma, PA should be kept in mind for the differential diagnosis in a case with headache, nausea, vomiting, ophthalmoplegia, visual loss, and electrolyte imbalance concurrent with an ongoing disease state 17).
One case of rare pituitary adenoma apoplexy caused by the rupture of an anterior communicating artery aneurysm. The patient was a 49-year-old male who had an untreated pituitary adenoma for 3 years. The patient experienced a sudden headache; computed tomography (CT) and magnetic resonance imaging (MRI) revealed pituitary adenoma apoplexy and significant subarachnoid hemorrhage. Cranial CT angiography (CTA) showed a communicating artery aneurysm. Supratentorial intracranial aneurysm clipping and pituitary adenoma resection were performed. The aneurysm was a ruptured aneurysm located inside the pituitary adenoma. During the surgery, the aneurysm was clipped, and the majority of the tumor was resected. The patient recovered well after the surgery and received radiotherapy.
This rare case demonstrates that when pituitary adenoma apoplexy is combined with subarachnoid hemorrhage, the possibility of a combined intrasellar aneurysm should be considered. During transsphenoidal tumor resection, aneurysm rupture should be avoided to prevent disastrous consequences 18).
A 42-year-old man who had been diagnosed of pituitary adenoma presented with a sudden onset of unconsciousness, left hemiplegia and right ptosis. Investigations revealed the development of pituitary apoplexy. The extension of tumor mass compressed the supraclinoid portion of the right internal carotid artery, resulting in the cerebral infarction in the right anterior and middle cerebral artery territory. Left anterior cerebral artery territory infarction was also found, which could be caused by vasospasm provoked by pituitary apoplexy. The patient underwent decompression surgery via transsphenoidal approach after four weeks' conservative treatment, and pathological examination revealed hemorrhage and necrosis of the pituitary adenoma. His symptoms improved within five months' follow-up. Since pituitary apoplexy producing cerebral infarction is rare, clinicians should be alert to that possibility, and delayed transsphenoidal surgery following conservative management with steroids is the appropriate management of such an occurrence 19).