title: Features of infratentorial-predominant posterior reversible encephalopathy syndrome.
abstract: Posterior reversible encephalopathy syndrome (PRES) is a neurotoxic process that typically occurs in the setting of immune dysregulation. In contrast to the characteristic pattern involving parieto-occipital and posterior frontal regions, predominant involvement of the infratentorial brain occurs in a minority of PRES patients. We examined six patients with infratentorial predominant posterior reversible encephalopathy syndrome (IPPRES) relative to those with typical PRES in terms of clinical factors of toxicity and outcomes. We review the current understanding of PRES pathophysiology. An institutional database of PRES patients was created through an IRB-approved search of the electronic record from 2007 to 2012. MR images were reviewed and classified by two neuro radiologists. Clinical data including laboratory data, blood pressure, and discharge outcome were collected through review of existing electronic medical records. Characteristics of the two groups were compared. Six cases among 80 PRES patients displayed an atypical distribution of signal abnormality predominantly involving the infratentorial brain. In IPPRES patients, signal abnormalities within the supratentorial brain, when present, showed a predominantly central distribution rather than the typical peripheral distribution. IPPRES patients showed higher rates of extreme hypertension, renal dysfunction, abnormal serum calcium, and abnormal serum magnesium relative to typical PRES patients. Outcomes were similar between the two groups. In our small series, IPPRES differs from typical PRES patients not only in the distribution of imaging abnormalities but also in rates of extreme hypertension and several laboratory indices. Despite these differences, clinical outcome in the IPPRES group was similar to that of typical PRES.
authors.affiliation: Department of Radiology, Neuroradiology Division Slot 556, University of Arkansas for Medical Sciences, 4301 W. Markham St., Little Rock, AR, 72205, USA. fitzgeraldryant@uams.edu.
authors.forename: Ryan T
authors.initials: RT
authors.lastname: Fitzgerald
authors.affiliation: Department of Radiology, Neuroradiology Division Slot 556, University of Arkansas for Medical Sciences, 4301 W. Markham St., Little Rock, AR, 72205, USA.
authors.forename: Rohan S
authors.initials: RS
authors.lastname: Samant
authors.affiliation: Department of Radiology, Neuroradiology Division Slot 556, University of Arkansas for Medical Sciences, 4301 W. Markham St., Little Rock, AR, 72205, USA.
authors.forename: Manoj
authors.initials: M
authors.lastname: Kumar
authors.affiliation: Department of Radiology, Neuroradiology Division Slot 556, University of Arkansas for Medical Sciences, 4301 W. Markham St., Little Rock, AR, 72205, USA.
authors.forename: Rudy
authors.initials: R
authors.lastname: Van Hemert
authors.affiliation: Department of Radiology, Neuroradiology Division Slot 556, University of Arkansas for Medical Sciences, 4301 W. Markham St., Little Rock, AR, 72205, USA.
authors.forename: Edgardo J
authors.initials: EJ
authors.lastname: Angtuaco
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000502:physiology; D001933:Brain Stem / Q000473:pathology*; D002531:Cerebellum / Q000473:pathology*; D005260:Female; D006261:Headache / Q000209:etiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D054038:Posterior Leukoencephalopathy Syndrome / Q000473:pathology* / Q000503:physiopathology*; D012189:Retrospective Studies; D012640:Seizures / Q000209:etiology; D055815:Young Adult
keywords: Brainstem; Cerebellum; Hypertensive encephalopathy; PRES; Posterior reversible encephalopathy syndrome