“Hot cross bun” sign in multiple system atrophy with predominant cerebellar ataxia: A comparison between proton density-weighted imaging and T2-weighted imaging

• Published in: European journal of radiology Vol. 81; no. 10; pp. 2848 - 2852
• Main Authors: Kasahara, Seiko, Miki, Yukio, Kanagaki, Mitsunori, Kondo, Takayuki, Yamamoto, Akira, Morimoto, Emiko, Okada, Tomohisa, Ito, Hidefumi, Takahashi, Ryosuke, Togashi, Kaori
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier Ireland Ltd 01.10.2012
• Subjects: Cerebellar Ataxia - pathology; Diffusion Magnetic Resonance Imaging - methods; Humans; Image Enhancement - methods; Image Interpretation, Computer-Assisted - methods; Magnetic resonance imaging; Male; Middle Aged; MSA-C; Multiple system atrophy; Multiple System Atrophy - pathology; Olivopontocerebellar atrophy; Pons - pathology; Proton density-weighted imaging; Protons; Radiology; Reproducibility of Results; Sensitivity and Specificity; “Hot cross bun” sign; Multiple system atrophy; MSA-C; Olivopontocerebellar atrophy; “Hot cross bun” sign; Magnetic resonance imaging; Proton density-weighted imaging
• ISSN: 0720-048X; 1872-7727
• DOI: 10.1016/j.ejrad.2011.12.012

Abstract Objective To investigate whether proton density-weighted imaging can detect the “hot cross bun” sign in the pons in multiple system atrophy with predominant cerebellar ataxia significantly better than T2-weighted imaging at 3 T. Methods Sixteen consecutive patients with multiple system atrophy with predominant cerebellar ataxia according to the Consensus Criteria were reviewed. Axial unenhanced proton density-weighted imaging and T2-weighted imaging were obtained using a dual-echo fast spin-echo sequence at 3 T. Two neuroradiologists independently evaluated visualisation of the abnormal pontine signal using a 4-point visual grade from Grade 0 (no “hot cross bun” sign) to Grade 3 (prominent “hot cross bun” sign on two or more sequential slices). Differences in grade between proton density-weighted imaging and T2-weighted imaging were statistically analysed using the Wilcoxon signed-rank test. Results In 11 patients (69%), a higher grade was given for proton density-weighted imaging than T2-weighted imaging. In 1 patient (6%), grades were the same (Grade 3) on both images. In the remaining 4 patients (25%), signal abnormalities were not detected on either image (Grade 0). The “hot cross bun” sign was thus observed significantly better on proton density-weighted imaging than on T2-weighted imaging ( P = 0.001). Conclusions The “hot cross bun” sign considered diagnostic for multiple system atrophy with predominant cerebellar ataxia is significantly better visualised on proton density-weighted imaging than on T2-weighted imaging at 3 T.