Colorectal anatomy in adults at computed tomography colonography: normal distribution and the effect of age, sex, and body mass index

BACKGROUND AND STUDY AIMS Computed tomography colonography (CTC) is an accurate tool for assessing the large intestinal anatomy. Our aims were to determine the normal distribution of in vivo colorectal anatomy and to investigate the effect of age, sex, and body mass index (BMI) on colorectal length. PATIENTS AND METHODS Asymptomatic adults who underwent primary CTC examination at a single institution over an 8-month period were evaluated. The interactive three-dimensional map was used to determine total and segmental lengths and number of acute-angle flexures. The two-dimensional multiplanar display was used to measure luminal diameters. The effects of age, sex, and BMI on colorectal lengths were examined. RESULTS The study cohort consisted of 505 consecutive adults (266 women, mean age 56.6 years). Mean total colorectal length was 189.5 +/- 26.3 cm and mean number of acute-angle flexures was 10.9 +/- 2.4. Total length for older adults (> 60 years) did not significantly differ from those who were younger than 60 years ( P = 0.22), although the transverse colon was significantly longer in older adults ( P = 0.04). Women had significantly longer colons than men (193.3 cm vs. 185.4 cm, P = 0.002), whereas overweight adults (BMI > 25) had significantly shorter colons compared with those with BMI <or= 25 (187.2 cm vs. 194.5 cm, P = 0.005). Differences in total length were predominately due to differences in the transverse colon. CONCLUSIONS Our results define the normal distribution of colorectal anatomy in an asymptomatic adult cohort, and may help to facilitate both colonoscopy training efforts and design of novel endoscopic devices. The transverse colon was the major determinant in length differences according to age, sex, and BMI, and was significantly longer in older adults, women, and thinner adults, respectively.

[1]  L. Walter,et al.  Association of older age and female sex with inadequate reach of screening flexible sigmoidoscopy. , 2004, The American journal of medicine.

[2]  J. Barkin,et al.  CT Colonography versus Colonoscopy for the Detection of Advanced Neoplasia , 2008 .

[3]  C. Messina,et al.  Factors that predict incomplete colonoscopy: thinner is not always better , 2000, American Journal of Gastroenterology.

[4]  L. Seeff,et al.  Is there endoscopic capacity to provide colorectal cancer screening to the unscreened population in the United States? , 2004, Gastroenterology.

[5]  S. Sadahiro,et al.  Analysis of length and surface area of each segment of the large intestine according to age, sex and physique , 2005, Surgical and Radiologic Anatomy.

[6]  T. Madiba,et al.  Radiological anatomy of the sigmoid colon , 2008, Surgical and Radiologic Anatomy.

[7]  D. Rex,et al.  Proof-of-concept study of the Aer-O-Scope omnidirectional colonoscopic viewing system in ex vivo and in vivo porcine models. , 2007, Endoscopy.

[8]  C. Williams,et al.  Intraoperative measurement of colonic anatomy and attachments with relevance to colonoscopy , 1995, The British journal of surgery.

[9]  Zamir Halpern,et al.  The aer-o-scope: proof of concept of a pneumatic, skill-independent, self-propelling, self-navigating colonoscope. , 2006, Gastroenterology.

[10]  S. Halligan,et al.  Can barium enema indicate when colonoscopy will be difficult? , 1995, Clinical radiology.

[11]  Perry J Pickhardt,et al.  Patient-controlled room air insufflation versus automated carbon dioxide delivery for CT colonography. , 2006, AJR. American journal of roentgenology.

[12]  S Halligan,et al.  Why is colonoscopy more difficult in women? , 1996, Gastrointestinal endoscopy.

[13]  C. Destrieux,et al.  Anatomical study of the length of the human intestine , 2002, Surgical and Radiologic Anatomy.

[14]  Z. Halpern,et al.  The Aer-O-Scope: Proof of the Concept of a Pneumatic, Skill-Independent, Self-Propelling, Self-Navigating Colonoscope in a Pig Model , 2006, Endoscopy.

[15]  B N S Bhatnagar,et al.  Study on the anatomical dimensions of the human sigmoid colon , 2004, Clinical anatomy.

[16]  David H. Kim,et al.  Anatomic factors predictive of incomplete colonoscopy based on findings at CT colonography. , 2007, AJR. American journal of roentgenology.