Satoshi Tsutsumi1, Juan Carlos Fernandez-Miranda2, Hisato Ishii3, Hideo Ono4, Yukimasa Yasumoto3. 1. Department of Neurological Surgery, Juntendo University Urayasu Hospital, 2-1-1 Tomioka, Urayasu, Chiba, 279-0021, Japan. shotaro@juntendo-urayasu.jp. 2. Department of Neurological Surgery, University of Pittsburgh School of Medicine, University of Pittsburg Medical Center, Pittsburgh, PA, USA. 3. Department of Neurological Surgery, Juntendo University Urayasu Hospital, 2-1-1 Tomioka, Urayasu, Chiba, 279-0021, Japan. 4. Division of Radiological Technology, Medical Satellite Yaesu Clinic, Tokyo, Japan.
Abstract
BACKGROUND AND PURPOSE: The fastigium cerebelli is an important topographical landmark for neurosurgeons and radiologists. However, few studies have characterized the morphology of the fastigium cerebelli. We aimed to investigate the fastigium cerebelli using postmortem specimens and magnetic resonance imaging (MRI) in vivo. MATERIALS AND METHODS: Three cadaveric brains were midsagittally sectioned for observing the fastigium cerebelli. Additionally, 66 outpatients underwent MRI, including sagittal T1-weighted imaging, axial T2-weighted imaging, and coronal constructive interference in steady-state (CISS) sequence. RESULTS: In the cadaveric specimens, the fastigium cerebelli was observed as a beak-like dorsal protrusion of the fourth ventricle. Its inner surface was observed as a small fovea. On serial CISS images, the fastigium cerebelli consistently possessed a pair of triangular-shaped, dorsal extensions lying parasagittally along the nodule. These extensions were classified as symmetrical, right-side dominant, or left-side dominant. The symmetrical type was the most predominant and comprised 60.6% of the extensions, while the right-side dominant and left-side dominant types comprised 13.6 and 25.8%, respectively. In 91% of the 66 patients, the number of slices covering the entirety of the dorsal extensions were the same on both sides. The fastigial angle (θ) formed by lines tangent to the superior and inferior medullary velums varied widely. CONCLUSIONS: The fastigium cerebelli has a pair of dorsal extensions lying parasagittally along the nodule. Coronal CISS sequence is useful in delineating the fastigium cerebelli in vivo.
BACKGROUND AND PURPOSE: The fastigium cerebelli is an important topographical landmark for neurosurgeons and radiologists. However, few studies have characterized the morphology of the fastigium cerebelli. We aimed to investigate the fastigium cerebelli using postmortem specimens and magnetic resonance imaging (MRI) in vivo. MATERIALS AND METHODS: Three cadaveric brains were midsagittally sectioned for observing the fastigium cerebelli. Additionally, 66 outpatients underwent MRI, including sagittal T1-weighted imaging, axial T2-weighted imaging, and coronal constructive interference in steady-state (CISS) sequence. RESULTS: In the cadaveric specimens, the fastigium cerebelli was observed as a beak-like dorsal protrusion of the fourth ventricle. Its inner surface was observed as a small fovea. On serial CISS images, the fastigium cerebelli consistently possessed a pair of triangular-shaped, dorsal extensions lying parasagittally along the nodule. These extensions were classified as symmetrical, right-side dominant, or left-side dominant. The symmetrical type was the most predominant and comprised 60.6% of the extensions, while the right-side dominant and left-side dominant types comprised 13.6 and 25.8%, respectively. In 91% of the 66 patients, the number of slices covering the entirety of the dorsal extensions were the same on both sides. The fastigial angle (θ) formed by lines tangent to the superior and inferior medullary velums varied widely. CONCLUSIONS: The fastigium cerebelli has a pair of dorsal extensions lying parasagittally along the nodule. Coronal CISS sequence is useful in delineating the fastigium cerebelli in vivo.
Authors: J A Roelants; I V Koning; M M A Raets; S P Willemsen; M H Lequin; R P M Steegers-Theunissen; I K M Reiss; M J Vermeulen; P Govaert; J Dudink Journal: AJNR Am J Neuroradiol Date: 2016-03-17 Impact factor: 3.825