Department of Radiology, Children's Hospital at Montefiore, Albert Einstein College of Medicine, 111 E 210th St, Bronx, NY 10467, USA.
AJR Am J Roentgenol. 2011 Aug;197(2):482-7. doi: 10.2214/AJR.10.5514.
Obesity is a growing clinical problem, especially among children of low socioeconomic status. Increased visceral abdominal fat is implicated in the metabolic syndrome and its health consequences. The purpose of this study is to validate measurement of a single MDCT slice as a predictor of total visceral abdominal fat and to correlate over a wide range of body mass indexes (BMIs).
A two-phase retrospective analysis was performed. For validation, MDCTs of 21 consecutive healthy children (8-14 years old) were reviewed. In these cases, visceral abdominal fat and subcutaneous abdominal fat area were calculated using a body fat analysis function from single 0.625-mm MDCT slices at the umbilicus and were compared with total visceral abdominal fat area as measured from T11 to the coccyx. Subsequently, visceral abdominal fat area was obtained from single slices at the umbilicus from abdominal MDCT scans of 146 consecutive healthy children (age range, 6-14 years; 80 boys and 66 girls; 77 Hispanic, 41 African American, 15 white, and 13 multiracial or other race) for whom BMI was available. Associations between visceral abdominal fat area and sex, race, and BMI were determined. Effective radiation dose for a 1.25-mm axial MDCT slice was calculated using a mathematic model that uses derived scaling factors for pediatric patients.
Visceral abdominal fat area obtained from a 0.625-mm slice at the umbilicus was highly correlated with total visceral abdominal fat area (r = 0.96; p < 0.0001). Visceral abdominal fat area from single slices at the umbilicus was significantly correlated with BMI (r = 0.72; p < 0.0001). Umbilical visceral abdominal fat area was significantly lower in African American children compared with others (median, 14 vs 22 cm(2); p = 0.02) and was not associated with sex. In our population, the effective radiation dose from the smallest obtainable slice was 0.015-0.019 mSv/37-54 kg of patient weight.
Visceral abdominal fat area calculated from a single abdominal MDCT slice obtained in children is highly correlated with total visceral abdominal fat and with BMI and involves limited radiation exposure.
肥胖是一个日益严重的临床问题，尤其是在社会经济地位较低的儿童中。内脏腹部脂肪增加与代谢综合征及其健康后果有关。本研究的目的是验证测量单一 MDCT 切片作为预测总内脏腹部脂肪的方法，并在广泛的体重指数 (BMI) 范围内进行相关性分析。
进行了两阶段回顾性分析。在验证阶段，回顾了 21 例连续的健康儿童 (8-14 岁) 的 MDCT。在这些病例中，使用体脂分析功能从脐部的单个 0.625mm MDCT 切片计算内脏腹部脂肪和皮下腹部脂肪面积，并与从 T11 到尾骨测量的总内脏腹部脂肪面积进行比较。随后，从 146 例连续健康儿童 (年龄范围 6-14 岁；男 80 例，女 66 例；77 例西班牙裔，41 例非裔美国人，15 例白人，13 例多种族或其他种族) 的腹部 MDCT 扫描中获得单个脐部切片的内脏腹部脂肪面积，这些儿童的 BMI 均可用。确定了内脏腹部脂肪面积与性别、种族和 BMI 之间的关联。使用针对儿科患者的推导比例因子的数学模型计算了 1.25mm 轴向 MDCT 切片的有效辐射剂量。
脐部 0.625mm 切片获得的内脏腹部脂肪面积与总内脏腹部脂肪面积高度相关 (r = 0.96；p < 0.0001)。脐部单一切片的内脏腹部脂肪面积与 BMI 显著相关 (r = 0.72；p < 0.0001)。与其他人相比，非裔美国儿童的脐部内脏腹部脂肪面积明显较低 (中位数，14 与 22cm²；p = 0.02)，且与性别无关。在我们的人群中，从最小可获得的切片获得的有效辐射剂量为 0.015-0.019mSv/37-54kg 患者体重。
从儿童腹部 MDCT 单一切片中计算出的内脏腹部脂肪面积与总内脏腹部脂肪和 BMI 高度相关，且辐射暴露有限。
