Reversible posterior leukoencephalopathy syndrome

Abstract

Reversible posterior leukoencephalopathy syndrome (RPLS) is characterized by subacute onset of headache, decreased alertness, vomiting, seizures, visuoperceptual disturbances, together with bilateral white matter lesions in posterior brain regions on brain imaging. The most frequently associated conditions related to RPLS are arterial hypertension and the use of immunosuppressive or cytotoxic treatment. T2-, Fluid Attenuation Inversion Recovery (FLAIR), and Apparent Diffusion Coefficient (ADC)-weighted magnetic resonance imaging (MRI) reveal hyperintensities in parietooccipital white matter but grey matter and other regions including frontal and temporal lobes, brainstem, cerebellum, basal ganglia, or even spinal cord may also be involved. According to ADC findings, the underlying pathophysiologic mechanism is probably one of vasogenic (rather than cytotoxic) oedema. These MRI findings help in differentiating RPLS from ischaemic events and other diseases resembling RPLS. Failure of cerebral autoregulation, endothelial dysfunction, disrupted blood-brain barrier, vasospasm, and direct toxic drug effects may all play a role in the pathophysiology of RPLS. Treatment consists of discontinuation of the causal drug, treatment of high blood pressure, and antiepileptic therapy. Clinical recovery and regression of radiological abnormalities are typically seen after early treatment. However, delay in diagnosis and treatment can result in irreversible brain damage, often in association with complicating cerebral infarction or haemorrhage.

Cortical blindness and posterior reversible encephalopathy syndrome in an older patient

“…This distribution of autonomous innervation within the brain vasculature could, therefore, explain the topography of the lesions observed in PRES. A vasospasm can be created secondarily, leading to tissular ischemia and irreversible cytotoxic oedema 8–10. At this time, ADC values will decrease in the lesion, as can be observed in stroke 11…”