Exploring the Complexities of Posterior Reversible Encephalopathy Syndrome: correlation data between clinical features and radiological patterns

Introduction : Posterior Reversible Encephalopathy Syndrome (PRES) is characterized by vasogenic brain edema, often triggered by hypertension or other known risk factors. Typical imaging shows bilateral parieto-occipital involvement, though rare cases affect deep brain structures like the deep brain structures. It is known that despite its definition, PRES includes a broad spectrum of radiological pictures, even if parietooccipital location remains the most common. This study explored possible clinical characteristics and risk factors correlating with different radiological phenotypes, hypothesizing a consequent different pathogenesis. Methods : A retrospective analysis of 50 PRES patients (2010–2023) assessed demographics, clinical features, comorbidities, imaging findings, and outcomes. MRI scans were evaluated for lesion location, symmetry, hemispheric or deep (atypical), and infratentorial distribution. Results : Severe hypertension correlated with deep brain involvement (26%) compared to typical supratentorial forms (0.5%, p = 0.0500). Surgical patients were less likely to have deep region involvement (0.6% vs. 60%, p < 0.0001). Seizures were more common in typical PRES (90%) versus deep variants (66%, p = 0.0500). Autoimmune diseases were associated with hemorrhage [OR 8.5, p = 0.0153] and DWI restriction [OR 8.05, p = 0.0149]. A significant link was also found between DWI restriction and severe arterial hypertension [OR 6.66 (CI 95% 1.37–32.29), p = 0.0184]. DWI restriction and hemorrhage were linked to brain sequelae [OR 21 and OR 20.55, respectively, p = 0.0013–0.0014]. Conclusion : Our study confirms a link between different brain regions involved in PRES and various risk factors, focusing on deep structures (atypical form) versus supratentorial involvement. It highlights correlations between imaging features (such as DWI restriction and hemorrhage) and brain sequelae at follow-up, emphasizing the multifaceted nature of PRES and the potential to identify patient subgroups with distinct pathophysiological mechanisms and varying risks of brain injury sequelae.