ANATOMICAL AND HISTOLOGICAL ASPECTS OF DEVELOPMENT OF URETER A FETAL CADAVERIC STUDY

Background The present study determines the morphometry of the fetal ureters and correlates it with the crown rump length (CRL) and the gestational age (GA) which would be a guide for their ultrasound visualization. A histological study of the fetal ureters was also carried out to highlight the epithelial and muscular components. Material and methods The length of the ureter was measured from the pelvi-ureteric junction up to its intravesical part. The sections of upper and lower ends of the ureters were processed histologically and were stained. The slides were observed under the light microscope with emphasis to the epithelium and the muscle coat. Results The length of the right ureter ranged from 26 to 44mm while on the left side it was 27 to 49mm. The transitional epithelium characterized by the superficial umbrella shaped cells was observed by 16th week. A thin coat of circularly arranged smooth muscle was seen interspersed with connective tissue at 12th week was observed which was arranged into an inner longitudinal smooth muscle layer by 36th week. The epithelial and muscle components were similar in the upper and the lower ends of the ureter. An outermost longitudinal muscle layer was not observed up to 36 weeks. Conclusion The present study did not compare the gender differences in the ureteric length. The study has given emphasis only to the epithelial and muscular components whereas the connective tissue components such as collagen and elastic fiber content and the distribution were not studied.