The Sentinel Clot Sign: a Useful CT Finding for the Evaluation of Intraperitoneal Bladder Rupture Following Blunt Trauma

OBJECTIVE: To evaluate the frequency and relevance of the "sentinel clot" sign on CT for patients with traumatic intraperitoneal bladder rupture in a retrospective study. MATERIALS AND METHODS: During a recent 42-month period, 74 consecutive trauma patients (45 men, 29 women; age range, 12-84 years; mean age, 50.8 years) with gross hematuria were examined by the use of intravenous contrast-enhanced CT of the abdomen and pelvis, followed by retrograde cystography. Contrast-enhanced CT scanning was performed by using a helical CT scanner. CT images were retrospectively reviewed in consensus by two radiologists. The CT findings including the sentinel clot sign, pelvic fracture, traumatic injury to other abdominal viscera, and the degree of intraperitoneal free fluid were assessed and statistically analyzed using the two-tailed x2 test. RESULTS: Twenty of the 74 patients had intraperitoneal bladder rupture. The sentinel clot sign was seen for 16 patients (80%) with intraperitoneal bladder rupture and for four patients (7%) without intraperitoneal bladder rupture (p < 0.001). Pelvic fracture was noted in five patients (25%) with intraperitoneal bladder rupture and in 39 patients (72%) without intraperitoneal bladder rupture (p < 0.001). Intraperitoneal free fluid was found in all patients (100%) with intraperitoneal bladder rupture, irrespective of an associated intraabdominal visceral injury, whereas 19 (35%) of the 54 patients without intraperitoneal bladder rupture had intraperitoneal free fluid (p < 0.001). CONCLUSION: Detection and localization of the sentinel clot sign abutting on the bladder dome may improve the accuracy of CT in the diagnosis of traumatic intraperitoneal bladder rupture, especially when the patients present with gross hematuria.

Spontaneous Rupture of a Bladder Diverticulum: A Case Report

We report on a case of spontaneous rupture of a bladder diverticulum, along with its cystographic and CT findings, in a 36-year-old woman. Three dimensional reformation of CT scanning is helpful for detecting the definite perforation site. To our knowledge, there has been no such report in the radiology literature describing the spontaneous rupture of a bladder diverticulum.

Brunn Nests Masquerading as Bladder Tumor: A Case Report

Brunn nests are the most common proliferative lesions of the bladder uroepithelium, but exuberant proliferation can mimic bladder tumor on radiologic imaging and cystoscopy. We describe a case of pathologically proven Brunn nests in a 34-year-old man, misdiagnosed as bladder tumor on preoperative imaging studies.

Primary Calcified T-Cell Lymphoma of the Urinary Bladder: A Case Report

Primary malignant lymphoma of the urinary bladder is extremely rare, and to our knowledge, no case described in the radiologic literature has been accompanied by calcification. We report a case in which the condition was associated with calcification, and describe the pelvic CT and MR imaging findings.

Xanthogranulomatous Cystitis: A Case Report

Xanthogranulomatous cystitis is a rare benign inflammatory disease that develops from a urachal remnant or occurs in association with pelvic surgery. Because it manifests as an infiltrative tumor-like lesion arising from the mid-line along the bladder dome and anterior abdominal wall, it is not easy to differentiate from The authors encountered one case of xanthogranulomatous cystitis, diagnosed by means of surgery and pathologic examination, and we report the related ultrasonographic and CT findings.

Contrast Enhanced Two-Phase Spiral CT of Urinary Bladder

PURPOSE: To determine optimal scan time for the early phase of two-phase spiral CT and to evaluate its usefulness in the detection and assessment of extension of urinary bladder lesions. MATERIALS AND METHODS: In four normal adults, we performed dynamic scanning and obtained time-density curves for internal and external iliac arteries and veins, and the wall of the urinary bladder. Sixty patients with 68 lesions of the urinary bladder or prostate underwent precontrast and two-phase spiral CT scanning. After injection of 100ml of noninonic contrast material, images for the early and delayed phases were obtained at 60 seconds and 5 minutes, respectively. We measured CT H.U. of the wall, the lesion, and lumen of urinary bladder as seen on axial scanning, in each image in which the lesion was best shown. For the detection of bladder lesions and assessment of their extension, precontrast, early-, and delayed phase images were compared. RESULTS: Dynamic study of normal adults showed maximum enhancement of bladder wall between 60 and 100 seconds. The difference of CT H.U. between bladder wall and the lesion was greatest in the early phase. The best detection rate (98.5%) was seen during this phase, and for the detection of bladder lesion, this same phase was superior or equal (66/68,97.1%) to the delayed phase. The precontrast image was also superior or equal (31/68,45.6%) to that of the delayed phase. For the assessment of extension of bladder lesion, the early phase was superior (36/68,52.9%) to the delayed phase, and precontrast image was superior (1/68, 1.5%) to that of the delayed phase. For determining the stage of bladder cancer, the early phase was most accurate if the stages was below B2 or D, while for stage C, the delayed phase was most accurate. CONCLUSION: In two-phase spiral CT scanning, we consider the optimal time for the early phase to be between 60 and 100 seconds after injection of contrast material. For the detection and assessment of extension of urinary bladder lesion, the early phase was superior to the late phase, and for evaluation of the ureter, the delayed phase was useful. The precontrast image was inferior to that of the delayed phase. We suggest that for the detection and assessment of extension of urinary bladder lesion without scanning of the precontrast image, two-phase spiral CT is reliable.