Related Experiment Video
Updated: Jan 22, 2026

Endoscopic Approach for Colloid Cyst Resection
Published on: May 23, 2025
Correlation between endoscopic features of the anastomosis after low anterior resection and postsurgical anorectal
Sumito Sato1,2, Manabu Shiozawa1, Mamoru Uchiyama1
1Department of Gastrointestinal Surgery, Kanagawa Cancer Center, Yokohama, Japan.
Background:
With low anterior resection (LAR) for rectal cancer, the oncologic outcomes are recently good. A diverting ileostomy is often created to protect the newly constructed anastomosis; seldom is a permanent stoma needed. Predicting postoperative anorectal function remains difficult, however. We speculated that the endoscopic appearance of the anastomosis before ileostomy closure is predictive of the post-operative anorectal function and tested our hypothesis retrospectively.
Methods:
Included in the study were 80 patients who, between September 2014 and August 2017, underwent LAR at Kanagawa Cancer Center. A diverting stoma had been created during the primary surgery, and ileostomy closure was performed about 6 months later. The anastomosis was examined endoscopically just before ileostomy closure, and the features were scored by two well-trained endoscopists. Daily defecation frequency and incontinence (Kirwan Score) were assessed after closure through physician-patient interview, and correlation between endoscopic feature scores and these measures of anorectal function was tested.
Results:
Documented endoscopic features included erythema in 79% of patients, erosion (45%), ulceration (5%), granulomatous change (41.3%), granular protrusions (17.5%); hemorrhagic (20.0%) or white-coated (30.0%) mucosa. Anastomosis stricture <9 mm was 17.5%. Median daily defecation frequency after ileostomy closure was 4 (range, 0-20). Moderate positive correlation was found between endoscopic scores and postoperative anorectal function (r=0.60, P<0.001).
Conclusions:
In recording and analyzing endoscopic features of the anastomosis before ileostomy closure in a large number of patients treated by LAR, we found that the features might indeed be clinically useful in predicting post-LAR anorectal function.
Related Concept Videos
Correlations
Correlation and Causation
Correlation versus Causation
If the dependent variable increases or decreases when the independent variable increases, there is a positive or negative...
Correlation
Two variables, for example, a and b, are said to be positively correlated if both variables move in the same direction. In other words, a positive correlation exists between two variables, a and b, if:
Muscles of the Anterior Neck
Correlation and Regression
Coefficient of Correlation
If you suspect a linear relationship between x and y, then r can measure how strong the linear relationship is.
What the VALUE of r tells us:
The value of r is always between –1 and +1: –1 ≤ r ≤ 1.
The size of the correlation r indicates the...

