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Show ORIGINAL CONTRIBUTION Sudden Death from Pituitary Apoplexy in a Patient Presenting with an Isolated Sixth Cranial Nerve Palsy Ronald E. Warwar, MD, Shaminder S. Bhullar, MD, Richard J. Pelstring, MD, and Ronald J. Fadell, MD Abstract: A 68- year- old diabetic, hypertensive man presented with a left sixth cranial nerve palsy. MRI demonstrated an inhomogeneous sellar mass encroaching on the left cavernous sinus. Two days later, a left third cranial nerve palsy developed. Within 24 hours, the patient went into cardiac arrest and died. An autopsy showed hemorrhage within a pituitary macroadenoma (" pituitary apoplexy"). Pituitary apoplexy should be considered a cause of acute isolated sixth cranial nerve palsy and may represent a life- threatening emergency that can be averted with emergent hormonal replacement and hypophysectomy ( J Neuro- Ophthalmol 2006; 26: 95- 97) Pituitary apoplexy is a clinical syndrome caused by infarction of the pituitary gland. It may occur within a normal or adenomatous gland ( 1). In the case of an adenoma, rapid tumor growth beyond its blood supply is thought to cause ischemic necrosis, hemorrhage, and sudden enlargement, which may result in compression of the remaining functioning pituitary, leakage of blood into the subarachnoid space, and direct compression of surrounding neural structures, including the hypothalamus ( 1). The resulting hypopituitarism, meningism, and hypothalamic dysfunction may lead to the commonly observed clinical findings of headache, nausea and vomiting, visual loss, ophthalmoplegia, decreased level of consciousness, electrolyte imbalance, impaired thermal regulation, hypotension, cardiac arrhythmia, and death ( 2,3). Although histopathologic evidence of apoplexy may be present in more than 25% of surgical hypophysectomy cases, clinical signs of pituitary apoplexy occur in less than 5% of such cases ( 2,3). Department of Surgery ( REW), Wright State University, Boonshoft School of Medicine ( SSB); Departments of Pathology ( RJP) and Radiology ( RJF), Kettering Medical Center, Dayton, Ohio. Address correspondence to Ronald E. Warwar, MD, 3100 Governors Place Boulevard, Dayton, OH 45409; E- mail: rwarwar@ warwareyegroup. com We report an adult who presented with an acute isolated sixth cranial nerve palsy. Because he had ample risk factors for an ischemic cause, no brain imaging was performed. Within days, an ipsilateral third cranial nerve palsy developed. Two days after hospitalization, while undergoing medical stabilization, the patient had hyperthermia, became asystolic, and died. Autopsy showed evidence of pituitary apoplexy and compression of the hypothalamus, the presumed cause of death. CASE REPORT A 68- year- old man presented with a two- week history of diplopia on left gaze. He had diabetes mellirus, hypertension, and chronic renal failure. Best- corrected visual acuity was 20/ 40 in both eyes, unchanged from baseline, and attributable to cataract. Confrontation visual fields and pupils were normal. There was a mild deficit of left abduction and an esotropia in left gaze. Mild background diabetic retinopathy was present in both eyes. The presumptive diagnosis was ischemic left cranial nerve six palsy. No brain imaging was performed. Six days later, the patient presented to the emergency department with a two- day history of headache and light- headedness. CT showed a sellar mass. MRI demonstrated that it was inhomogeneous, with flecks of high signal ( on T2 but not Tl sequences) suggestive of recent hemorrhage. It extended into the left cavernous sinus ( Fig. 1). These features were consistent with bleeding into a pituitary adenoma (" pituitary apoplexy"), the rapid expansion into the cavernous sinus accounting for the sixth cranial nerve palsy. Serum tests demonstrated subnormal thyroid stimulating hormone, free T4 and Cortisol, and elevated follicle stimulating hormone, luteinizing hormone, and prolactin. Sodium was 134 mEq/ L and potassium was 5.2 mEq/ L. The patient was normotensive. Two days later, while still an inpatient, he developed left ptosis, a left adduction deficit, and a mydriatic left pupil, consistent with a left third cranial nerve palsy. An emergent CT was without change from the earlier study. Before completing a repeat MRI study, the patient was noted to have an oral temperature of 103.1° F. Shortly J Neuro- Ophthalmol, Vol. 26, No. 2, 2006 95 J Neuro- Ophthalmol, Vol. 26, No. 2, 2006 Warwar et al FIG. 1. MRI at the time of acute left sixth cranial nerve palsy. A. Pre- contrast T1- weighted coronal study shows a sellar mass extending into the suprasellar space and left cavernous sinus. There is no obvious high signal to suggest recent bleeding. B. Post- contrast T1- weighted coronal study shows diffuse enhancement. C. T2- weighted axial study shows fleck- like high signal within the mass suggestive of recent bleeding (" pituitary apoplexy"). thereafter, he was found unconscious and in cardiac asystole. Despite resuscitative measures and treatment with high-dose intravenous corticosteroids, the patient died. An autopsy showed a3.0x2.2x2.0cm pituitary adenoma with various 1- 4 mm areas of hemorrhage and necrosis within the tumor ( Fig. 2). There was no subarachnoid blood. The presumptive cause of death was cardiovascular collapse secondary to hypothalamic compression. DISCUSSION Our patient presented with an isolated sixth cranial nerve palsy as the only manifestation of an expanding, hemorrhagic pituitary adenoma. Sudden lateral expansion of the adenoma into the cavernous sinus accounts for ophthalmoplegia, consisting more commonly of third cranial palsy than sixth ( or fourth) cranial nerve palsy. The ocular motor cranial nerves appear to be resistant to slow compression but are very susceptible to sudden compression, as seen with apoplexy ( 2). Thus, the onset of any degree of ophthalmoplegia in a patient with a known pituitary adenoma should alert the clinician to the possibility of apoplexy. CT scanning may detect a suprasellar mass greater than 1 cm, using conventional 5 mm- thick axial sections. Specific imaging of the sella with 2 mm sections will increase the sensitivity of detection. However, MRI is more sensitive and is the modality of choice. In the setting of apoplexy, CT scanning may not detect small hemorrhages but is more sensitive than MRI in detecting acute hemorrhages less than three hours old. Acute hemorrhages more than 3 hours old will appear isotense on Tl- weighted images and hypotense on T2- weighted images; signal intensity will increase over the ensuing five days, at which time blood will appear hypertense on Tl- weighted and T2- weighted images ( 4). Previous retrospective studies have shown that nonsurgical management of pituitary apoplexy in stable patients with absent or minimal visual and/ or neuro- ophthalmic deficits has resulted in visual, ocular motor nerve, and endocri-nologic outcomes similar to those undergoing surgery ( 5,6). It has also been suggested that the outcome of surgical A 2> ' • • • • - . v . ; . . £#£*&#* mm , N " X ' * * r o • - ; - .• • 9 s> I t " t » • . J r « . . - ' V tJfflgQ** • 5--** ^-^ ys FIG. 2. A. Necropsy gross specimen of the pituitary adenoma. Note the large dark zones of hemorrhagic necrosis. B. Histopathology shows hemorrhagic necrosis ( above right) and viable pituitary adenoma ( below left) ( hematoxylin and eosin stain, xlOO). 96 © 2006 Lippincott Williams & Wilkins Pituitary Apoplexy J Neuro- Ophthalmol, Vol. 26, No. 2, 2006 decompression is similar when performed either within or after one week of presentation ( 5,6). In all cases, immediate medical management of electrolyte and hormonal disorders is indicated. The present case illustrates several important considerations. Given the ready availability of non- invasive, high sensitivity imaging, patients with acute isolated sixth nerve palsies, including those with strong ischemic risk factors, should be considered for an imaging study to rule out potentially lethal conditions such as pituitary apoplexy. The presence of an ocular motor cranial nerve palsy in the setting of a pituitary adenoma strongly suggests rapid tumor expansion by apoplexy. Such palsies are present in less than 10% of non- apoplectic adenomas but in 40% of apoplexy cases ( 5- 7). We acknowledge that death from pituitary adenoma apoplexy is very rare, with no deaths having been reported in two reviews of 78 patients ( 5,6). However, if ophthalmoplegia or rapidly progressive visual loss is noted, emergent transsphenoidal decompression should be strongly considered after medical stabilization to prevent potentially fatal rebleeding. REFERENCES 1. Semple PL, Webb MK, de Villiers JC, et al. Pituitary apoplexy. Neurosurgery 2005; 56: 65- 73. 2. Verrees M, Arafah BM, Selman WR. Pituitary tumor apoplexy: characteristics, treatment, and outcomes. Neurosurg Focus 2004; 16: 1- 7. 3. Lubina A, Olchovsky D, Berezin M, et al. Management of pituitary apoplexy: clinical experience with 40 patients. Acta Neurochir 2005; 147: 151- 7. 4. Freeman WD, Maramattom B, Czervionke L, et al. Pituitary apoplexy. Neurocrit Care 2005; 3: 174- 6. 5. Sibal L, Ball SG, Connolly Y et al. Pituitary apoplexy: a review of clinical presentation, management and outcome in 45 cases. Pituitary 2004; 7: 157- 63. 6. Ayuk J, McGregor EJ, Mitchell RD, et al. Acute management of pituitary apoplexy: surgery or conservative management? Clin Endocrinol 2004; 61: 747- 52. 7. Oruckaptan HH, Senmevsim O, Ozcan OE, et al. Pituitary adenomas: results of 684 surgically treated patients and review of the literature. Surg Neurol 2000; 53: 211- 9. 97 |
