title: The suprapineal recess of the third ventricle: an anatomic study with magnetic resonance imaging.
abstract: OBJECTIVE
  The suprapineal recess (SPR) is a small, backward extension of the third ventricle. Few radiological studies have investigated the morphology of the SPR. Here, we explore the SPR with magnetic resonance (MR) imaging.
  
  
  METHODS
  A total of 124 patients underwent thin-slice MR imaging examinations with T2-weighted imaging and the constructive interference steady-state (CISS) sequence. Imaging data were transferred to a workstation for analysis.
  
  
  RESULTS
  The pineal gland (P) was delineated in 99% of the patients on T2-weighted imaging and 100% of the patients on the CISS sequence. In contrast, the SPR was identified in 27% of the patients on T2-weighted imaging and 82% of the patients on the CISS sequence. The location of the P relative to the lowest point of the splenium was roughly classified into two types. Of them, the anterior P location was the more frequent type and observed in 73% of the patients. The angle formed by the roof and floor of the SPR showed remarkable interindividual diversity. A membranous posterior extension with variable length, spanning between the posterosuperior margin of the P and Galenic complex was found in 55% of the identified SPRs on T2-weighted imaging and 45% on the CISS sequence.
  
  
  CONCLUSIONS
  The SPR is a distinct structure with diversity in appearance among individuals but commonly extends posterior to the P. High-resolution MR imaging is useful for delineating the SPR in vivo.
authors.affiliation: Department of Neurological Surgery, Juntendo University Urayasu Hospital, 2-1-1 Tomioka, Urayasu, Chiba, 279-0021, Japan. shotaro@juntendo-urayasu.jp.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tsutsumi
authors.affiliation: Division of Radiological Technology, Medical Satellite Yaesu Clinic, Tokyo, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Ono
authors.affiliation: Department of Neurological Surgery, Juntendo University Urayasu Hospital, 2-1-1 Tomioka, Urayasu, Chiba, 279-0021, Japan.
authors.forename: Yukimasa
authors.initials: Y
authors.lastname: Yasumoto
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D020542:Third Ventricle / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D055815:Young Adult
keywords: MRI; Pineal gland; Pineal recess; Suprapineal recess; Third ventricle