Summary:Purpose: Reversible posterior leukoencephalopathy syndrome (RPLS) is an increasingly recognized brain disorder most commonly associated with malignant hypertension, toxemia of pregnancy, or the use of immunosuppressive agents. When associated with acute hypertension, RPLS typically occurs concurrently with the fulminant clinical syndrome of hypertensive encephalopathy. We describe occipital lobe seizures, in the setting of only moderate elevations of blood pressure, as the major clinical manifestation of RPLS.Methods: Two patients from the Dent Neurologic Institute are presented with clinical and magnetic resonance imaging (MRI) correlation.Results: New onset secondarily generalized occipital seizures were noted, with MRI findings consistent with RPLS. Both of the patients had chronic renal failure and a moderate acute exacerbation of chronic hypertension. Other features of hypertensive encephalopathy were lacking, such as headache, nausea, papilledema, and an altered sensorium. Magnetic resonance imaging (MRI) showed edematous lesions primarily involving the posterior supratentorial white matter and corticomedullary junction, consistent with RPLS. With lowered blood pressure, the MRI lesions resolved and the patients became seizure-free without requiring chronic anticonvulsant therapy.Conclusions: Occipital seizures may represent the only major neurologic manifestation of RPLS due to acute hypertension, especially in patients with renal failure. Other evidence of hypertensive encephalopathy, such as cerebral signs and symptoms, need not be present. Blood pressure elevations may be only moderate. Early recognition of this readily treatable cause of occipital seizures may obviate the need for extensive, invasive investigations. Despite the impressive lesions on MRI, prompt treatment of this disorder carries a favorable prognosis. Key Words: Hypertensive encephalopathy-leukoencephalopathy-MRI-Seizures-Occipital lobe.Occipital lobe seizures are a rare form of partial epilepsy (I), with a variety of underlying causes that may be detected by magnetic resonance imaging (MRI). Commonly recognized etiologies include fixed causes such as traumatic brain injury, mass lesions, developmental anomalies, and chronic encephalitis (1-3). In addition, reversible posterior leukoencephalopathy syndrome (RLPS), elaborated by Hinchey et al. (4), is an increasingly recognized brain disorder of various etiologies which may include occipital lobe dysfunction and seizures accompanied by posterior MRI brain lesions (5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). When secondary to malignant hypertension, RPLS typically occurs on MRI along with the fulminant clinical syndrome of hypertensive encephalopathy (4,12-15,2 1,22 hypertension who developed new-onset, secondarily generalized occipital seizures with disappearing posteriorly-predominant MRI brain lesions. Occipital lobe epilepsy is a known manifestation of RPLS-eclampsia (23). However, occipital seizures have not been previously reported as the major manifestatio...