목적: 삼차원 회전혈관영상을 이용하여 성별과 연령군에 따른 정상 두개내혈관 직경의 분포를 파악하였다. 대상과 방법: 정상으로 추정되는 두개내혈관 177예(125명)를 대상으로 하였다. 회전혈관조영술 후 재구성한 삼차원 혈관영상에서, 내경동맥 4부위(해면동분절, 안동맥부위, 상상부위, 원위 내경동맥부위)와 중뇌동맥 2부위(근위부, 원위부), 그리고 전뇌동맥 1부위(중간부) 순으로 각각의 직경을 측정하고 성별, 연령군별(<30세, 30-39, 40-49, 50-59, 60$\leq$) 평균을 구하였다. 각 부위에서 성별에 따른 차이 및 중뇌동맥에서 연령층간(저령층<50세, 고령층$\geq$50세) 직경의 차이를 분석하였다. 결과: 성별, 부위별 직경의 평균치는 다음과 같다: 남자(mean$\pm$SD); 4.61$\pm$0.69, 3.96$\pm$0.60, 3.48$\pm$0.45, 3.61$\pm$0.50, 2.44$\pm$0.32, 2.44$\pm$0.37, 1.81$\pm$0.32, 여자; 4.29$\pm$0.57, 3.83$\pm$0.56, 3.37$\pm$0.56, 3.52$\pm$0.48, 2.32$\pm$0.37, 2.30$\pm$0.36, 1.76$\pm$0.34. 성별 차이는 40대에서 분명하였고, 전뇌동맥을 제외한 6부위에서 남자가 여자에 비해 유의하게 크거나(내경동맥 4 지점과 원위부 중뇌동맥) 큰 경향(근위부 중뇌동맥)을 보였다. 중뇌동맥 근위부 직경은 남자 고령층(2.59$\pm$0.35 mm)이 저령층(2.35$\pm$0.27 mm)에 비하여 의미 있게 컸으며(p value<0.05), 여자에서는 고령층의 수치(2.38$\pm$0.37 mm)가 저령층(2.28$\pm$0.37 mm)에 비하여 큰 경향을 보였으나 통계적으로 유의하지는 않았다(p value: 0.14). 원위부 직경은 남녀 각각에서 고령층(남자, 2.63$\pm$0.43; 여자, 2.39$\pm$0.35 mm)이 저령층(남자, 2.34$\pm$0.29; 여자, 2.21$\pm$0.34 mm)에 비하여 의미 있게 큰 수치를 보였다. 결론: 정상 두개내혈관 직경은, 성별 차이가 40대에서 분명하였고 남자가 여자에 비하여 크거나 큰 경향을 보였으며, 중뇌동맥 직경은 성별에 상관없이 고령층이 저령층에 비하여 의미있게 크거나 큰 경향을 나타내었다. 고령층의 중뇌동맥 근위부 직경은 남자가 2.59$\pm$0.35 mm, 여자가 2.38$\pm$0.37 mm이었고, 원위부 직경은 남자가 2.63$\pm$0.43 mm, 여자가 2.39$\pm$0.35 mm 이었다.
Purpose: To evaluate the distribution of normal intracranial artery diameter according to sex and age, using three-dimensional reconstruction rotational angiography. Materials and Methods: One hundred and twenty-five adults with normal intracranial arteries who underwent 3D rotational angiography (n=177) were included in this study. The arterial diameter was measured at four sites of the internal carotid artery (cavernous, paraophthalmic, supraclinoid, and distal), that of the middle cerebral artery at two (proximal and distal), and that of the anterior cerebral artery at one (middle). For each sex and age group (<30, 30-39, 40-49, 50-59, $\geq$60 years), the mean diameter of the artery at these seven sites was calculated, and differences analysed. In addition, the middle cerebral artery diameter was compared between a younger group (<50 years) and an older group ($\geq$50 years). Results: The mean diameter at each site for each sex was as follows: male (mean${\pm}$SD): 4.61${\pm}$0.69, 3.96${\pm}$0.60, 3.48${\pm}$0.45, 3.61${\pm}$0.50, 2.44${\pm}$0.32, 2.44${\pm}$0.37, 1.81${\pm}$0.32; female: 4.29${\pm}$0.57, 3.83${\pm}$0.56, 3.37${\pm}$0.56, 3.52${\pm}$0.48, 2.32${\pm}$0.37, 2.30${\pm}$0.36, 1.76${\pm}$0.34. For those in their 40s, the diameter at five sites (all four sites of the internal cerebral artery and a distal middle cerebral artery) was significantly greater in males than in females. For other age groups, however, the difference between the sexes was absent, or was significant at only one (cavernous internal cerebral artery for those in their 30s) or two (proximal and distal middle cerebral artery for those in their 50s) of the seven sites. In the older age group, the diameter of the proximal middle cerbral artery was 2.59${\pm}$0.35 mm in males and 2.38${\pm}$0.37 mm in females. For the distal middle cerebral artery, the corresponding figures were 2.63${\pm}$0.43 and 2.39${\pm}$0.35 mm, respectively. For both sexes, the differences between the two age groups were significant. Conclusion: For those in their 40s, the normal diameter of the intracranial artery at most arterial sites was significantly greater in males than in females. The normal diameter of the middle cerebral artery was significantly greater or tended to be greater among the older group than the younger group (for males and females, respectively, 2.59${\pm}$0.35 mm and 2.38${\pm}$0.37 mm at the proxinal site, and 2.63${\pm}$0.43 mm and 2.39${\pm}$0.35 mm at the distal site).