OCCIPITAL LOBE SEIZURES AS THE MAJOR CLINICAL MANIFESTATION OF REVERSIBLE POSTERIOR LEUKOENCEPHALOPATHY SYNDROME - MAGNETIC-RESONANCE-IMAGING FINDINGS

Purpose: Reversible posterior leukoencephalopathy syndrome (RPLS) is a n increasingly recognized brain disorder most commonly associated with malignant hypertension, toxemia of pregnancy, or the use of immunosup pressive agents. When associated with acute hypertension, RPLS typical ly occurs concurrently with the fulminant clinical syndrome of hyperte nsive encephalopathy. We describe occipital lobe seizures, in the sett ing of only moderate elevations of blood pressure, as the major clinic al manifestation of RPLS. Methods: Two patients from the Dent Neurolog ic Institute are presented with clinical and magnetic resonance imagin g (MRI) correlation. Results: New onset secondarily generalized occipi tal seizures were noted, with MRI findings consistent with RPLS. Both of the patients had chronic renal failure and a moderate acute exacerb ation of chronic hypertension. Other features of hypertensive encephal opathy were lacking, such as headache, nausea, papilledema, and an alt ered sensorium. Magnetic resonance imaging (MRI) showed edematous lesi ons primarily involving the posterior supratentorial white matter and corticomedullary junction, consistent with RPLS. With lowered blood pr essure, the MRI lesions resolved and the patients became seizure-free without requiring chronic anticonvulsant therapy. Conclusions: Occipit al seizures may represent the only major neurologic manifestation of R PLS due to acute hypertension, especially in patients with renal failu re. Other evidence of hypertensive encephalopathy, such as cerebral si gns and symptoms, need not be present. Blood pressure elevations may b e only moderate. Early recognition of this readily treatable cause of occipital seizures may obviate the need for extensive, invasive invest igations. Despite the impressive lesions on MRI, prompt treatment of t his disorder carries a favorable prognosis.