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Show ORIGINAL CONTRIBUTION Simultaneous Posterior Ischemic Optic Neuropathy, Cerebral Border Zone Infarction, and Spinal Cord Infarction After Correction of Malignant Hypertension Jae-Hwan Choi, MD, Kwang-Dong Choi, MD, Ji Soo Kim, MD, Hak Jin Kim, MD, Ji-Eun Lee, MD, and Seoung Jae An, MD Abstract: A 31-year-old woman developed bilateral posterior ischemic optic neuropathy and infarctions of the cerebral arterial border zones and spinal cord after correction of malignant hypertension. Although a few reports have described patients with neurologic abnormalities after treatment of malignant hyperten-sion, full clinical and neuroimaging documentation of this combination of findings has not occurred. This case report suggests that the relative hypotension of autoregulatory failure induced by treatment of malignant hypertension may give rise to these neurologic complications. (J Neuro-Ophthalmol 2008;28:198-201) Malignant hypertension refers to severe hypertension and organ damage including progressive renal failure, heart failure, and encephalopathy, and requires urgent correction of blood pressure (1-3). A few reports have described patients with neurologic abnormalities after treatment of malignant hypertension (4-9). Nevertheless, simultaneous optic neuropathy, cerebral border zone infarction, and spinal cord infarction have not been fully described previously. CASE REPORT A 31-year-old woman presented with a 2-hour history of epigastric pain. She was previously healthy except for taking oral contraceptives for 5 years. On admission, her blood pressure was 270/120 mm Hg. She denied a previous history of systemic hypertension. Visual acuities were 10/20 in both eyes, and confron-tation visual fields were normal. Grade III hypertensive retinopathy was present on ophthalmoscopy. Hematocrit was 27.1%, and platelet count was 48,000/mm3. The peripheral blood smear showed frag-mented and polychromatophilic red blood cells. The serum creatinine level was 1.8 mg/dL, and lactate dehydrogenase was 2,041 U/L. Malignant hypertension was diagnosed, and she received 20 mg hydralazine intravenously and 10 mg nifedipine sublingually followed by 10 mg fosinopril and 8 mg candesartan orally, which lowered her blood pressure to 120/80 mm Hg within 1 day (Fig. 1). At this time she developed visual blurring in both eyes, which rapidly progressed to complete blindness over several hours. She also complained of bilateral leg weakness, voiding difficulty, and sacral numbness. Visual acuities were no light perception in both eyes, and the pupils were fully dilated without reaction to light. Ophthalmoscopy showed grade III hypertensive retinopa-thy with normal optic discs (Fig. 2A). She could not raise either leg against gravity. Pain and temperature senses were symmetrically reduced over the sacral dermatomes. Deep tendon reflexes were increased, and the Babinski sign was present bilaterally. T2 brain MRI revealed high signal areas in the medulla bilaterally (Fig. 3), which were hyperintense on diffusion imaging and isointense on apparent diffusion coefficient (ADC) mapping. T2 high signal areas were also found in the superficial border zones between the middle cerebral artery (MCA) and anterior cerebral artery (ACA) territories, which were hyperintense on diffusion imaging and hypointense on ADC mapping (Fig. 3). Serum aldosterone, renin, epinephrine, and norepi-nephrine concentrations and urinary excretion of epineph-rine, norepinephrine, and vanillylmandelic acid were normal. Departments of Neurology (J-HC, K-DC), Radiology (HJK), Ophthalmology (J-EL), and Nephrology (SJA), Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, Busan, Korea; and Department of Neurology (JSK), Seoul National University Bundang Hospital, Seoul, Korea. Address correspondence to Kwang-Dong Choi, MD, Department of Neurology, College of Medicine, Pusan National University, 1-10 Ami-dong, Seo-gu, Busan 602-739, Korea; E-mail: kdchoi@medimail.co.kr 198 J Neuro-Ophthalmol, Vol. 28, No. 3, 2008 MRI and MRA of the kidney to assess an underlying cause for hypertension showed no abnormalities. After maintenance of the blood pressure within the normal range, leg weakness had resolved completely 1 day later. However, 2 months later, visual acuities remained hand movements in both eyes and voiding difficulty had not improved. Bilateral optic disc pallor was now evident (Fig. 2B), and brain MRI showed persistent high signal areas throughout the medulla and spinal cord (Fig. 4). DISCUSSION After correction of malignant hypertension, our patient developed bilateral posterior ischemic optic neuropathy, bilateral cerebral border zone infarctions, and extensive spinal infarction with myelopathy. This combi-nation of findings has not been clinically and neuro-radiologically documented before. There are eight previously reported patients with ischemic optic neuropathy after treatment of malignant hypertension. (4-7) Three of them showed simultaneous optic neuropathy and myelopathy (sphincter disturbance in two and flaccid paraplegia in the remaining one) (4,6). Another 2 patients presented with isolated paraplegia after treatment of malignant hypertension (8,9). In our patient, clinical and radiologic features support ischemic damage owing to relative hypotension after correction of malignant hypertension as the underlying mechanism of neurologic abnormalities rather than the malignant hypertension itself. The patient did not have neurologic symptoms during the period of high blood pressure, and she had ischemic optic neuropathy rather than retrogeniculate visual pathway infarction, the site of visual loss in patients with visual disturbances from malignant hypertension (posterior reversible encephalopathy syn-drome) (10-13). In addition, there was MRI evidence of infarction in the medulla and spinal cord, territories associated with hypotensive rather than hypertensive stroke (10-15). In 7 of the 8 reported patients with ischemic optic neuropathy after treatment of malignant hypertension, the optic discs were already swollen during the hypertensive crisis. In the eighth patient, initially blurred optic disc margins became more swollen after correction of malignant hypertension, an indication of anterior ischemic optic neuropathy. In our patient, the optic discs were normal when she complained of visual loss and the pupils were unreactive to light, an indication of posterior ischemic optic neuropathy. The spinal cord, particularly its watershed zone centered at the mid-thoracic level, is a frequent site of ischemic injury (16). However, global ischemia may also affect other levels of the spinal cord, as apparently occurred in our patient. Mild degrees of ischemia may involve the lumbosacral spinal cord (69%), intermediate degrees may affect the lumbosacral and cervical spinal cord in a patchy manner (9%), and severe degrees of ischemia may result in holocord necrosis (17%) (17). FIG. 1. Time course of our patient's blood pressure, doses of antihyper-tensive agents, and development of blindness and paraplegia. 199 Ischemic Optic Neuropathy Plus J Neuro-Ophthalmol, Vol. 28, No. 3, 2008 Among the reported patients with ischemic optic neuropathy after treatment of malignant hypertension, the visual outcome has been dismal in five, as it was in our patient. One reported patient showed remarkable recovery of vision after prompt restoration of blood pressure with dopamine and norepinephrine, and the remaining 2 patients recovered limited vision after saline infusion, corticosteroids, or stellate ganglion block (7,8). Remark-ably, in our patient and in all reported patients, neurologic complications occurred even though blood pressure remained within a conventionally normal level, probably because of a failure of autoregulation. The upper and lower limits of systemic blood pressure between which autor-egulation occurs are reset at a higher level in chronic hypertension (18); thus, a sudden lowering of the systemic blood pressure even to normal levels may bring it below the lower limit of autoregulation, in which case cerebral perfusion will fail. FIG. 3. MRI performed 1 day after correction of systemic hypertension. A. T2 axial MRI shows high signal areas in the medulla bilaterally (arrows). B. Diffusion imaging study shows focal high signal (restricted diffusion) areas in the superficial border zone between the middle cerebral artery and anterior cerebral artery territories (arrows). FIG. 2. A. Optic fundi 1 day after correction of systemic hypertension show cotton wool spots and normal optic discs. B. Optic fundi 2 months later show bilateral optic disc pallor. 200 q 2008 Lippincott Williams & Wilkins J Neuro-Ophthalmol, Vol. 28, No. 3, 2008 Choi et al REFERENCES 1. Aggarwal M, Khan IA. 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