Advanced

AJNR - American Journal of Neuroradiology

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Saeki, N. Articles by Yamaura, A. Search for Related Content PubMed PubMed Citation Articles by Saeki, N. Articles by Yamaura, A.

American Journal of Neuroradiology 26:566-571, March 2005
© 2005 American Society of Neuroradiology

BRAIN

MR Imaging of Normal Perivascular Space Expansion at Midbrain

Naokatsu Saeki^a, Motoki Sato^a, Motoo Kubota^a, Yoshio Uchino^a, Hisayuki Murai^a, Yuichiro Nagai^a, Hiroshi Ishikura^a, Seitaro Nomura^a, Iichiro Matsuura^a and Akira Yamaura^a

^a From the Departments of Neurological Surgery and Pathology, Chiba University Graduate School of Medicine

Address reprint requests to Naokatsu Saeki, Department of Neurological Surgery, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba City, Chiba 260-8670, Japan

BACKGROUND AND PURPOSE: A previous investigation of the MR imaging findings in the midbrain reported expanded perivascular (PV) spaces in only the ponto-mesencepalic junction (PMJ) in 20% of healthy subjects, whereas pathologically expanding PV spaces have been reported at the mesencephalo-diencephalic junction (MDJ) as multi-lobulated, cystic lesions with signal intensity compatible with that of CSF that cause aqueductal stenosis. To clarify the anatomical distinctions between normally expanded and pathologically expanding PV spaces, we defined their distribution in the normal midbrain by using high-spatial-resolution MR imaging.

METHODS: Heavily T2-weighted MR imaging was performed in 115 adult subjects with neurologic complaints without cerebral disease. Histologic studies were performed from two normal midbrain blocks.

RESULTS: Expanded PV spaces were visible at the PMJ in 87% of subjects and at the MDJ in 63% of subjects. On axial images, ovoid or linear lesions with signal intensity compatible to CSF were present behind the cerebral peduncle at both the PMJ and MDJ. These areas varied from less than 1 mm to 5 mm (maximum diameter on coronal sections). Histologic studies confirmed the distribution of expanded PV spaces, as noted on MR images.

CONCLUSION: This study, by using high-spatial-resolution MR imaging, revealed that expanded PV spaces were visible at the PMJ and MDJ. Our finding of expanded PV spaces normally present at the MDJ may be related to pathologically expanding PV spaces, which should be kept in mind as a differential diagnosis for intraparenchymal cystic lesions in the midbrain with signal intensity compatible to CSF.

This article has been cited by other articles:

				R. M. Kwee and T. C. Kwee Virchow-Robin Spaces at MR Imaging RadioGraphics, July 1, 2007; 27(4): 1071 - 1086. [Abstract] [Full Text] [PDF]