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The diameter of the rectum on ultrasonography as a diagnostic tool for constipation in children with dysfunctional
Aart J Klijn1, Marino Asselman, Marianne A W Vijverberg
1University Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands.
Insights
Ultrasonography accurately measures the transverse diameter of the rectum, aiding in diagnosing constipation in children with lower urinary tract dysfunction. This non-invasive method offers a valuable tool for pediatric gastroenterologists.
Area of Science:
- Pediatric gastroenterology
- Diagnostic imaging
- Urology
Background:
- Constipation is a common issue in children, often associated with lower urinary tract dysfunction.
- Accurate diagnosis is crucial for effective management and preventing complications.
- Current diagnostic methods may require further refinement for specific pediatric populations.
Purpose of the Study:
- To evaluate the accuracy of the transverse rectal diameter measured by ultrasonography as an additional diagnostic parameter for constipation.
- To compare rectal diameter in constipated children with lower urinary tract dysfunction to a control group.
Main Methods:
- A comparative study included 49 children, divided into a constipated group (n=23) with dysfunctional voiding and a control group (n=26) with normal defecation.
- Rectal transverse diameter was measured using a 7.5 MHz abdominal ultrasound probe with a filled bladder.
- Defecation questionnaires and physical examinations were also conducted.
Main Results:
- The mean transverse rectal diameter was significantly larger in the constipated group (4.9 cm) compared to the control group (2.1 cm) (p < 0.001).
- No significant differences in age or time since last bowel movement were observed between groups.
- No patients reported defecation urgency during the ultrasound measurement.
Conclusions:
- Transverse rectal diameter measured by lower abdominal ultrasound is an accurate additional parameter for diagnosing constipation.
- This ultrasonographic finding is particularly useful in children with nonneurogenic bladder-sphincter dyssynergia.
- Ultrasonography offers a valuable, non-invasive tool to support constipation diagnosis in pediatric urology and gastroenterology.
Purpose:
We proved the accuracy of the transverse diameter of the rectum on ultrasonography as an additional parameter for diagnosing constipation in children with lower urinary tract dysfunction.
Materials And Methods:
The diameter of the rectum on bladder ultrasonography in a constipated group of patients with dysfunctional voiding was compared to this diameter in a control group of patients with a normal defecation pattern. A total of 49 children were included. Group 1 consisted of 23 patients with a positive history of dysfunctional voiding and, according to pediatric gastroenterological practice, constipation. Control group 2 consisted of 26 patients without lower urinary tract dysfunction and a normal defecation pattern. In each group a defecation questionnaire was administered and physical examination of the abdomen was done. In all patients a 7.5 MHz probe was used to measure the transverse diameter of the rectum behind the bladder on ultrasonography. The probe was applied on the abdominal skin approximately 2 cm above the symphysis. Measurement was performed with a filled bladder at an angle of about 15 degrees downward from the transverse plane.
Results:
In constipated group 1 the mean diameter of the rectum was 4.9 cm (95% CI 4.4 to 5.3). In the control group the mean diameter of the rectum was 2.1 cm (95% CI 1.8 to 2.4). In group 1 the diameter of the rectum was significantly larger than in group 2 (p < 0.001). None of the patients had a sensation to defecate during the investigation. There was no significant difference in age between the 2 groups (p = 0.20) and no significant difference between them in the period between the last time that stool was passed prior to the time of rectal measurement (p = 0.16).
Conclusions:
The transverse diameter of the rectum measured by lower abdominal ultrasound provides an additional accurate parameter with which to diagnose constipation in patients with nonneurogenic bladder-sphincter dyssynergia.
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