Persistent Visual Field Defects Eight Months after Posterior Reversible Leukoencephalopathy Syndrome

Posterior reversible encephalopathy syndrome (PRES) is not commonly encountered in routine ophthalmologic practice. It is characterized by acute or subacute neurological changes in the form confusion, lethargy and visual disturbances (1-3), most commonly occurring in the clinical setting of acute hypertension, eclampsia and solid organ transplantation. It is also associated with connective tissue disorders and the use of cytotoxic or immunosuppressive medications. Vision loss occurs as the result of vasogenic edema, primarily involving the parietal and occipital cortex in 98% of cases (4). Diagnosis is based on clinical presentation and the characteristic MRI demonstration of posterior cerebral hyperintensities best seen on FLAIR images (5). Radiographic findings usually resolve partially or completely with treatment of the underlying condition and, in most cases, vision is restored (1).