Background: Measurement of rectal diameter by ultrasonography helps the clinician in the diagnosis of chronic constipation in children for whom rectal examination cannot be performed. The aim of the study is to determine the rectal diameter and anterior wall thickness values in constipated and healthy children and to evaluate the feasibility of ultrasonography in the diagnosis of functional constipation in children who refuse digital rectal examination. Methods: One hundred forty constipated and 164 healthy children participated in the study. All patients were divided into 4 subgroups according to their ages (≤3 years [group I], 3.1-6 years [group II], 6.1-12 years [group III], and >12 years [group IV]) and were referred to the radiology department. The measurement was made from above the symphysis pubis, under the ischial spine, and at the bladder neck. Anterior wall thickness measurement was performed. The measurements were recorded according to the presence or absence of fecal mass in the rectum. Results: Constipated children with fecal mass positive group III was found to have significant difference in all of the planes in rectal diameter measurement. Rectum anterior wall thickness measurement was found to be higher in constipated patients with fecal mass (+) compared to the control. Its measurements in constipated patients in group II, group III, and group IV with no fecal mass were found to be statistically higher than the control group. Conclusion: The measurement of rectal diameter and anterior wall thickness by ultrasonography as a noninvasive method was performed in children who did not want the digital rectal examination, and it may be useful in the diagnosis of constipation. Cite this article as: Doğan G, Keçeli M, Yavuz S, Topçu A, Kasırga E. Measurement of rectal diameter and anterior wall thickness by ultrasonography in children with chronic constipation. Turk J Gastroenterol. 2022;33(12):1062-1068.

Superb microvascular imaging (SMI) is a new Doppler technique. Superb microvascular imaging can observe microvascular and low-velocity blood flow. Superb microvascular imaging is available in 2 modes: color SMI (cSMI) and monochrome SMI (mSMI). To evaluate testicular flow, we have compared color Doppler ultrasound (CDUS), power Doppler ultrasound (PDUS), Advanced Dynamic Flow (ADF), cSMI, and mSMI techniques. Fifty-six participants less than 36 months of age were included in the study (mean age, 18.21 ± 1.5 months). One of the testes examined was in the scrotal sac, and the other was undescended testis (UT), and its location was at the level of the lower/middle inguinal canal. Testicular vascularization was evaluated with the CDUS, PDUS, ADF, and SMI techniques. Spot and linear signal encoding detected in the parenchyma were recorded between 0 and III for each technique. At the level of the testicle hilus, the outer boundary of the testicle was drawn manually along the long axis of each testis, and the vascularity index (VI) was automatically calculated from this area on the cSMI method. There was no significant relationship between normal and undescended testicles in terms of age, weight, height, testicle volume, and VI. Superb microvascular imaging was found to be superior in showing testicular vascularity, especially UT. The power of detecting Doppler signal in mSMI is significantly higher than in other methods (P < 0.001). The most valuable method according to the power of detecting testicular vascularity was mSMI. Next were cSMI, ADF, PDUS, and CDUS. In conclusion, the SMI technique should be included in vascular examination in pediatric patients with UT. The SMI technique can play an important role in assessing vascularization of UT.