Fetal sigmoid colon mesentery - In relevance in fetal ultrasound application. A pilot study.

INTRODUCTION

Ultrasound examinations during pregnancy are routine procedures used to detect fetal congenital malformations. Ultrasound monitoring of sigmoid colon mesenterial development could be useful for early detection of subjects at risk of sigmoid colon volvulus.

OBJECTIVE

The aim of our paper was to assess the sigmoid colon length, and sigmoid colon mesentery width and height in the late fetal period, and, using the results, to estimate the surface area of the mesocolon (in mm2) in living fetuses. Moreover, we attempted to repeat some of these measurements in living fetuses using ultrasound imaging.

METHODS

The study was carried out on 209 formalin fixed human fetuses (100 female and 109 male) aged from 4th to 7th gestational months (102-203 days), with a crown-rump length of 132-342mm. The length of the sigmoid colon, as well as the height and width of its mesentery were measured. The surface area of the mesocolon was estimated. Correction for formalin induced shrinkage was applied. Pilot ultrasound examinations of live fetuses were performed.

RESULTS

Mean values of sigmoid colon length, mesenteric width and height (formalin fixed fetuses) for respective gestational ages were: month 4: 21.46±6.7mm, 6.80±2.1mm, 5.5±1.49mm; month 5: 27.32±1.2mm, 7.62±2.01mm, 7.33±2.17mm; month 6: 47.56±9.57mm, 11.68±3.8mm, 10.3±3.05mm; month 7: 56.92±17.48mm. 15.32±8 mm, 12.81±3.16mm. The surface area ranges of the sigmoid colon mesentery found for respective gestational months (intrauterine fetuses) were as follows: month 4: 33.24-51.95mm2; month 5: 49.63-77.6mm2; month 6: 106.89-167.15mm2 and month 7: 145.69-272.53mm2.

CONCLUSION

The surface area of the sigmoid colon mesentery can be used as a simple parameter applied in fetal ultrasonographic evaluation. The development of the sigmoid colon accelerates in the 6th gestational month, and decelerates in the 7th gestational month. The sigmoid colon mesentery width was larger than its height between the 4th and 7th gestational months.