Abstract TP228: The Overlap of Posterior Reversible Encephalopathy Syndrome and Reversible Cerebral Vasoconstriction Syndrome

Abstract

Introduction: Posterior reversible encephalopathy syndrome (PRES) is a clinical syndrome with typical neuroimaging findings of vasogenic cerebral edema in posterior brain regions. Reversible cerebral vasoconstriction syndrome (RCVS) is diagnosed when there is reversible cerebral vessel narrowing and often with thunderclap headache. The two diseases have overlap in clinical and radiographic features. Objective: To compare clinical presentation, vascular abnormalities and imaging findings among PRES and RCVS. Methods: We searched patients in electronic health record at a single tertiary center from January 2008 to December 2018. Inclusion criteria was 18 years or older with clinical and radiographic evidence of PRES or RCVS. PRES was diagnosed by clinical presentation and presence of vasogenic edema on radiographic imaging. RCVS was determined by clinical presentation and transient arterial stenosis. Patient demographics, presenting symptoms, comorbid conditions, and imaging findings were compared between PRES and RCVS populations. Analysis was performed using Fisher’s exact test Results: Seventy-four patients with PRES and 24 patients with RCVS met inclusion criteria. The median age and presenting blood pressure did not differ between PRES and RCVS groups. PRES population consisted of fewer females (70%) compared to RCVS (92%, p=0.05). There was no significant difference in frequency of DWI lesions in PRES (37%) and RCVS (24%, p=0.308). Among patients who had arterial imaging, arterial stenosis was seen in 28% (13/46) of PRES. The occurrence of > 50% FLAIR reversibility was more common in PRES (67%) and seen less frequently in RCVS (27%, p=0.008). Conclusion: There is radiographic overlap between PRES and RCVS. About a quarter of PRES have arterial stenosis, while about a quarter of the RCVS group had FLAIR reversibility.