URACHAL REMNANTS - SONOGRAPHIC ASSESSMENT

Objective: To evaluate the frequency of the visualization of urachal r emnants (UR) with ultrasound and to determine their sonographic patter ns. Subjects and methods: Two hundred and fifty consecutive patients w ere referred for abdominal and/or pelvic ultrasonography, 83 who had u rinary tract symptoms. Patient age ranged from 1 month to 91 years (me an = 35 years). Patients were classified into four groups: (1) <16 yea rs (n = 47) (2) 16-35 years (n = 100), (3) 36-55 years (n = 49), (4) g reater than or equal to 56 years (n = 54). Ultrasonography was perform ed using 3.75 MHz and 7.5 MHz transducers. Ultrasound criterion for di agnosis was a midline mass located between the rectus abdominus muscle and the upper part of the anterior bladder wall. Results: UR were fou nd in 90 cases (36%). UR demonstration was more frequent in groups 1 ( 61.7%) and 2 (49%) and 3 (20.4%) and 4 (3.7%). UR were nodular (87%) o r tubular in structure (13%). Echogenicity was similar to or greater t han adjacent muscle in 51% and less than in 49%. The length, width, an d thickness mean and standard deviation values were 13.5 +/- 4.7 mm, 1 2.6 +/- 5 mm, and 5.2 +/- 1.5 mm, respectively. UR were observed in 50 % of the asymptomatic patients of groups 1 and 2. Conclusion: Urachal remnants are commonly demonstrated with ultrasound, particularly in yo ung patients. They should be considered to be a normal variant unless there is an increase in size or they are accompanied by clinical signs , without other possible causes for symptoms. (C) 1996 John Wiley & So ns, Inc.