ORIGINAL ARTICLE A volumetric study of the corpus callosum in 20s and 40s Korean people Beob-Yi Lee Æ Jin-Hun Sohn Æ Mi-Hyun Choi Æ Su-Jeong Lee Æ Hyo-Seong Kim Æ Jae-Woong Yang Æ Jin-Seung Choi Æ Hyung-Sik Kim Æ Jeong-Han Yi Æ Gye-Rae Tack Æ Soon-Cheol Chung Received: 21 February 2009 / Accepted: 29 June 2009 / Published online: 14 July 2009 Ó Springer-Verlag 2009 Abstract The purpose of this study was to measure the average corpus callosum volume of normal Koreans (aged in their 20s or 40s) and to analyze the effects of gender, age, and body parameters, such as height and weight on corpus callosum size. Magnetic resonance brain images were recorded for 68 people in their 20s (29 men, 39 women) and 91 in their 40s (36 men, 55 women). Intra- cranial volume was calculated using cerebral size and corpus callosum volume was normalized by covariance method. To investigate the effect of gender and age on corpus callosum volume, two-way analysis of variance, which used gender (two levels) and age (two levels) as independent variables, was employed. Multiple regression analysis was carried out to investigate the effect of body parameters, such as height and weight, according to the age and gender on the changes in corpus callosum volume. The average corpus callosum volume of Korean men (11.09 cm 3 ) was larger than that of Korean women (9.61 cm 3 ). There was no significant difference in corpus callosum volume between 20s (10.43 cm 3 ) and 40s (10.12 cm 3 ). There was a positive relationship between body weight and corpus callosum volume for 20s, but not for 40s. Keywords Corpus callosum  MRI  Volumetry  Korean Introduction The corpus callosum is the largest structure of white matter fibers connecting the two cerebral hemispheres. The corpus callosum is an important structure in the understanding of schizophrenia (Panizzon et al. 2003), epilepsy (Hermann et al. 2003), unipolar depression (Lacerda et al. 2005), and bipolar disorder (Brambilla et al. 2003). Therefore, accu- rate measurement of the corpus callosum volume in healthy men and women can provide common norm against which to compare patient groups (Sullivan et al. 2001). It was reported that the size of corpus callosum remains to be relatively stable at least through the seventh decade (Johnson et al. 1994; Driesen and Raz 1995; Sullivan et al. 2001). Previous studies by investigators on changes in cor- pus callosum size according to gender have shown contro- versial results. Some results showed that there was a gender difference in corpus callosum size (Johnson et al. 1994; Driesen and Raz 1995; Bishop and Wahlsten 1997; Salat et al. 1997; Sullivan et al. 2001; Allen et al. 2003), while others could not find any differences (Weis et al. 1989; Kertesz et al. 1990; Constant and Ruther 1996). Some investigators reported that there might be a relationship between the volume and weight of the brain and body parameters such as height and weight (Pakkenberg and Voigt 1964; Nopoulos et al. 2000; Chung et al. 2005; Koh et al. 2005). These studies reported that the effect of body parameters could be different according to gender and age. B.-Y. Lee Department of Anatomy, School of Medicine, Konkuk University, Seoul, South Korea J.-H. Sohn Department of Psychology, Institute for Brain Research, Chungnam National University, Daejon, South Korea M.-H. Choi  S.-J. Lee  H.-S. Kim  J.-W. Yang  J.-S. Choi  H.-S. Kim  J.-H. Yi  G.-R. Tack  S.-C. Chung (&) Department of Biomedical Engineering, Research Institute of Biomedical Engineering, College of Biomedical and Health Science, Konkuk University, 322 Danwall-dong, Chungju, Chungbuk 380-701, South Korea e-mail: scchung@kku.ac.kr 123 Brain Struct Funct (2009) 213:463–467 DOI 10.1007/s00429-009-0209-5