The diverticular jet effect: Color Doppler differentiation of bladder diverticula from other pelvic fluid collections

Abstract

Diverticula of the bladder are commonly found in patients with chronic elevated bladder pressure. The sonographic appearance of bladder diverticula is relatively straightforward in the majority of cases, especially if the point of communication between the diverticulum and bladder is demonstrated.' Occasionally, however, this point of communication may be difficult to demonstrate with gray-scale images. We describe a case in which the diagnosis of a bladder diverticulum was not obvious on gray-scale images but was definitively shown with the use of color Doppler interrogation. Case 1A 5-year-old boy with a history of Chiari I1 malformation, myelomeningocele, and associated neurogenic bladder dysfunction was seen for an ultrasound examination of the urinary tract. A ventriculoperitoneal shunt had been placed for the hydrocephalus and was apparently functioning well. Ultrasound examination of the upper urinary tract was normal. Evaluation of the bladder revealed irregularity of the bladder wall with moderate mural thickening. A 1.5 cm x 1.8 cm x 1.4 cm sonolucent collection was seen adjacent to the right lateral bladder wall, and the possibility of a bladder diverticulum or CSF collection within the lower peritoneal cavity was raised. Further evaluation of this fluid collection failed to show definite communication with the bladder, and the origin of the collection remained uncertain.

Urinary bladder diverticula: sonographic diagnosis and interpretive pitfalls.

“…Additional considerations could have included hematoma, mesenteric cyst, duplication cyst, and urachal cyst. [4][5][6][7] Diverticula can be mistaken for other lesions for several reasons. First, the communication with the bladder may be small and narrow.a Resolution of such a narrow mouth communication would be substantially compromised-if not precluded-when Figure 1 A, Cystic adnexal mass (arrow) in an 84 year old woman raised initial concern for the possibility of a cystic ovarian tumor.…”

“…4). 6,7 Color Doppler technique also was useful in demonstrating the location of ureteral jets in the bladder, distinguishing the neck of the mass from the ureteral orifice, and thereby dispelling the potential confusion with dilated ureters.…”

Prenatal Diagnosis of a Congenital Bladder Diverticulum

“…The discovery of a pelvic mass of undetermined origin should suggest a systematic search for a bladder diverticulum [6]. The diagnosis of this anomaly is facilitated when the connection between the bladder and the mass is established, either by visualization of a fluid-filled cavity which is posterolateral to the bladder and which fills up when the bladder empties, or by color Doppler identification of a stream of urine between the two structures [6,[10][11][12][13]. Ultrasound (optimal with 5 MHz probes) will of course take long and requires patience, with modifications of the angles of view as well as of the image resolution needed [6,[10][11][12][13].…”

“…Depending on the ultrasound image and before any further exploration, possible diagnoses could include a ureterocele, a urinoma, a necrotic bladder tumor, a urachal cyst, a seminal vesicle cyst, an ovarian cyst, a lymphadenopathy, a lymphocele or compartmentalized ascites, a mesenteric cyst, malrotation of an intestinal loop, an abscess, or a hematoma [6,11,15].…”

“…The diagnosis of this anomaly is facilitated when the connection between the bladder and the mass is established, either by visualization of a fluid-filled cavity which is posterolateral to the bladder and which fills up when the bladder empties, or by color Doppler identification of a stream of urine between the two structures [6,[10][11][12][13]. Ultrasound (optimal with 5 MHz probes) will of course take long and requires patience, with modifications of the angles of view as well as of the image resolution needed [6,[10][11][12][13]. Several factors can affect these parameters [6,12,14]: narrowed communication between the bladder and the diverticulum can either lead to an uninformative Doppler or prevent complete draining of the diverticulum; an excessively large bladder diverticulum can be mistaken for the bladder, or poor filling of the diverticulum gives it a heterogeneous appearance, simultaneously solid and liquid, and this suggests an abdominal or pelvic cyst.…”