Urethral length in female infants and its relevance in the repair of cloaca

Abstract

Aim of the study: The goals of urinary reconstruction in urogenital sinus and cloacal repair include: (1) positioning of the bladder neck above the urogenital diaphragm to maximize future urinary continence, and (2) creating a visible urethra that can be catheterized if needed. A recent algorithm in cloacal reconstruction proposed a urethral length of 1.5 cm as the key determinant in deciding whether to perform a total urogenital mobilization or a urogenital separation, the hypothesis being that a 1.5 cm length urethra is needed for the patient to remain dry. We wondered if the normal female urethral length correlated with this empiric technical determinant.

Methods: We reviewed voiding cystourethrograms of healthy female patients between ages 6 and 36 months and measured the patient's urethral length.

Results: Ninety-one children were included. The mean urethral length for patients age 6-12 months was 2.50 cm, age 12-24 months was 2.31 cm, and age 24-36 months was 2.59 cm. There was no difference between the urethral length in the three groups (p = 0.38). Of 91 patients, 87 (96%) had a urethral length >1.5 cm.

Conclusion: A urethra of at least 1.5 cm was present in the majority of normal control patients. We believe therefore that for urogenital sinus and cloacal repair, surgeons can extrapolate that patients need a 1.5 cm urethra at the end of the reconstruction. Additional follow-up is needed to determine if this urethral length as an independent factor maintains dryness in the long term after cloacal repair.

Type of study: Case Series.

Level of evidence: III.

Keywords: Anorectal malformation; Cloaca; Total urogenital mobilization; Urogenital separation; Urogenital sinus.