From the Research
Diagnostic Criteria for Posterior Reversible Encephalopathy Syndrome (PRES)
The diagnostic criteria for PRES are not strictly standardized, but several studies have identified common clinical and radiological features associated with the condition 1, 2, 3, 4, 5. The key diagnostic criteria include:
- Acute onset of symptoms such as headache, confusion, seizures, and visual disturbances
- Presence of vasogenic edema on brain imaging, particularly in the parieto-occipital regions
- Reversibility of neuroimaging abnormalities
- Association with underlying conditions such as hypertensive encephalopathy, eclampsia, collagen disease, and severe infection
Clinical Features
The clinical features of PRES can vary, but common symptoms include:
- Seizures
- Headache
- Visual disturbances
- Altered mental status
- Focal neurological deficits
Radiological Features
The radiological features of PRES typically involve:
- Bilateral subcortical vasogenic edema predominantly affecting the parieto-occipital regions
- Hyperintensity on fluid-attenuated inversion recovery images and apparent diffusion coefficient mapping
- Isointensity on diffusion-weighted images
- Reversibility of neuroimaging abnormalities
Diagnostic Evaluation
Diagnostic evaluation for PRES typically involves:
- Magnetic resonance imaging (MRI) to confirm the presence of vasogenic edema and rule out other conditions
- Computed tomography (CT) scans may also be used, but MRI is preferred
- Laboratory studies to exclude alternative diagnoses and identify underlying causes
- Clinical assessment to identify symptoms and signs associated with PRES 3, 4