Posterior Reversible Encephalopathy:

Posterior reversible encephalopathy syndrome [PRES (also known as posterior reversible leukoencephalopathy syndrome)] presents with rapid-onset symptoms such as headache seizures altered consciousness and visual disturbance. It is often but by no means always associated with acute hypertension. If recognized and treated promptly the clinical syndrome usually disappears within a week and changes seen on magnetic resonance imaging (MRI) resolve within days to weeks.The severity of clinical symptoms varies. For example visual disturbance may manifest as blurred vision homonymous hemianopsia or even cortical blindness.