Urachal cyst: radiological findings and review of cases. Poster No.: C-0334 Congress: ECR 2014 Type: Scientific Exhibit Authors: I. Álvarez Silva 1, A. M. Fernández Martínez 1, T. Cuesta 1, S. Molnar Fuentes 1, J. D. Samper Wamba 2 ; 1 León/ES, 2 LEON/ES Keywords: Cysts, Comparative studies, Ultrasound, CT, Urinary Tract / Bladder, Abdomen DOI: 10.1594/ecr2014/C-0334 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. www.myesr.org Page 1 of 6
Aims and objectives Urachal abnormalities are rare, with an incidence of 2 cases per 300,000 hospital admissions. The urachus, or median umbilical ligament, is a midline tubular structure that extends from the apex of the bladder up to the umbilicus. It is a vestigial remnant of at least two embryonic structures: cloaca and allantois. Its obliteration happens around the 32nd week of the intrauterine development. The persistence of any part of the urachus will result in the urachal congenital anomalies derived from it, which are anatomically divided into four types: persistence of the urachus, umbilical-urachal sinus, vesicourachal diverticulum, and urachal cyst. The cyst is the second most common urachal anomaly. It develops if the urachus closes in both the umbilicus and the bladder sides, remaining somewhere between these two endpoints, most often in the lower third of the urachus. The purposes of this study are: 1. To analyse the usefulness of imaging methods in the diagnosis of urachal cyst. 2. To identify the most common complication of urachal cysts. Methods and materials Retrospective descriptive study of urachal cysts diagnosed in our Hospital since 1999 until 2012 by imaging methods. Results Ten out of twelve urachal cysts, detected during the thirteen years examined, were initially diagnosed by abdominal ultrasound techniques. In four cases they were incidental findings during an ultrasound scan, not requiring additional studies or treatment for being asymptomatic and without histological confirmation. Seven other patients underwent abdominal-pelvic CT, with intravenous contrast subsequently to confirm the diagnosis. In the remaining case, CT was performed as the Page 2 of 6
initial test. Pelvic MRI was also performed in one case and voiding cystourethrogram in another one, as additional tests. Five of them were infected at the time of diagnosis. Another one was a urachal carcinoma. This superinfection shows up on CT as highlighted wall thickening after intravenous contrast administration, and as a soft tissue mass with heterogeneous echotexture on ultrasound scan. These radiological findings make it difficult to differentiate between an infected urachal cyst and an urachal carcinoma. Therefore, in most cases, percutaneous needle biopsy or fluid aspiration are necessary for definitive diagnosis and treatment planning. Images for this section: Page 3 of 6
Fig. 2: Sagittal multiplanar reconstruction. Page 4 of 6
Fig. 3: Coronal multiplanar reconstruction. Page 5 of 6
Conclusion 1. CT and ultrasound are the imaging methods of choice for the diagnosis of urachal cyst, which is shown in both tests, as a fluid-filled cavity located in the midline lower abdominal wall, below the umbilicus or above the bladder. 2. Infection is the most common complication, with almost half of the cases examined showing it at the time of diagnosis. Personal information References 1. Jeong-Sik Y, Ki Whang K, Hwa-Jin L, Young-Jun L. Urachal Remnant diseases: spectrum of CT and US findings. Radiographics 2001;21:451-461. 2. Nagasaki A, Handa N, Kawanami T. Diagnosis of urachal anomalies in infancy and childhood by contrast fistulography, ultrasound and CT. Pediatr Radiol 1991; 21:321-323. 3. Spataro RF, Davis RS, McLachlan MSF, et al. Urachal abnormalities in the adults. Radiology 1983; 149:659-663. 4. Morin ME, Tan A, Baker DA, Sue HK. Urachal cyst in the adult: ultrasound diagnosis. AJR Am J Roentgenol 1979; 132:831-832. 5. Friedland GW, Devries PA, Matilde NM, Cohen R, Rifkin MD. Congenital anomalies of the urinary tract. In: Pollack HM, ed. Clinical urography. Philadelphia, Pa: Saunders, 1990; 559-787. 6. Goldman IL, Caldamone AA, Gauderer M, et al. Infected urachal cysts: a review of 10 cases. J Urol 1988; 140:375-378. 7. Sheldon CA, Clayman RV, Gonzalez R, Williams RD, Fraley EE. Malignant urachal lesions. J Urol 1984; 131:1-8. 8. Brick SH, Friedman AC, Pollack HM, et al. Urachal carcinoma: CT findings. Radiology 1988; 169:377-381. 9. Korobkin M, Cambier L, Drake J. Computed tomography of urachal carcinoma. J Comput Assist Tomogr 1988; 12:981-987. 10. Rao BK, Scanlan KA, Hinke ML. Abdominal case of the day. AJR Am J Roentgenol 1986; 146:1074-1079. 11. Chen WJ, Hsieh HH, Wan YL. Abscess of urachal remnant mimicking urinary bladder neoplasm. Br J Urol 1992; 69:510-512. Page 6 of 6