PT  - JOURNAL ARTICLE
AU  - Schneider, J.F.
AU  - Floemer, F.
TI  - Maturation of the Olfactory Bulbs: MR Imaging Findings
AID  - 10.3174/ajnr.A1501
DP  - 2009 Jun 01
TA  - American Journal of Neuroradiology
PG  - 1149--1152
VI  - 30
IP  - 6
4099  - http://www.ajnr.org/content/30/6/1149.short
4100  - http://www.ajnr.org/content/30/6/1149.full
SO  - Am. J. Neuroradiol.2009 Jun 01; 30
AB  - BACKGROUND AND PURPOSE: The detection of time-related maturational changes of the olfactory bulb (OB) on MR imaging may help early identification of patients with abnormal OB development and anatomic-based odor-cueing anomalies.MATERIALS AND METHODS: Two separate reviewers retrospectively analyzed coronal T2-weighted spin-echo MR images of the frontobasal region in 121 patients. There were 22 patients who underwent MR imaging examinations several times, accounting for a total of 156 studies. Age range was 1 day to 19.6 years. OBs were bilaterally identified in all cases and categorized according to their shape and signal intensity.RESULTS: Three different anatomic patterns were identified. In pattern 1 (median age, 15 days; age range, 1–168 days), the OBs were round to oval with a continuous external T2-hypointense rim and a prominent T2-hyperintense central area. In pattern 2 (median age, 287 days; age range, 4 days–22 months), the OBs were U shaped, with thinning and concave deformation of the superior layer. A hyperintense central area on T2-weighted images was still visible. In pattern 3 (median age, 5.2 years; age range, 107 days–19.6 years), the OBs were small, round, or J shaped with a more prominent lateral part. No difference in signal intensity between the central area and the peripheral layer was identified anymore.CONCLUSIONS: The OBs show time-related maturational changes on MR imaging. There is a progressive reorganization of the peripheral neuronal layers and signal intensity changes of the central area, which are completed at the end of the second year, paralleling cerebral maturational changes.