Communications of the pelvic extraperitoneal spaces and their relation to the abdominal extraperitoneal spaces: helical CT cadaver study with pelvic extraperitoneal injections.

PURPOSE: To evaluate flow patterns and anatomic appearances in the pelvic extraperitoneal spaces and to determine their relation to the abdominal extraperitoneal spaces. MATERIALS AND METHODS: Helical computed tomographic (CT) guidance was used for injection of up to 1,000 mL of iodinated contrast material into one pelvic extraperitoneal space in each of five cadavers. Staged-volume injections into two prevesical spaces, one paravesical space, and one perivesical space were followed by helical CT. RESULTS: The injected pelvic extraperitoneal spaces freely communicated with each other and with the perirenal and anterior and posterior pararenal spaces of the abdomen. This abdominal communication was via the large infrarenal space posteriorly and the circumferential extraperitoneal spaces about the peritoneal cavity bounded deeply and superficially by the parietal peritoneum and transversalis fascia, respectively. The contrast material reached the diaphragm superiorly and the femoral vascular sheath space and inguinal canals inferiorly. After crossing the midline both anterior and posterior to the peritoneal cavity, the contrast material reached the mesenteric root in four cadavers and the propericardial space of the thorax in two cadavers. CONCLUSION: Intercommunication of the various extraperitoneal compartments occurs predominantly via the fascial-defined spaces, which contain mainly adipose tissue, but potential conduits exist through the communicating neurovascular structures where the fascia is anatomically perforated.

Anatomic communications between the three retroperitoneal spaces: determination by CT-guided injections of contrast material in cadavers.

OBJECTIVE: A variety of retroperitoneal diseases such as pancreatitis, infection, and trauma may cause fluid collections in the three major retroperitoneal spaces. The purpose of our study was to elucidate flow patterns of fluid between the various compartments to assist the clinical-radiologic assessment and treatment of various retroperitoneal diseases. MATERIALS AND METHODS: In eight cadavers, CT guidance was used to selectively inject 35-1000 ml of contrast medium by hand or power injector into five perirenal, two posterior pararenal, and two anterior pararenal spaces. After the injections, CT of the entire abdomen and pelvis was done with 10-mm-thick sections at intervals of 10-40 mm. All images were reviewed in detail by a group of experienced body imagers to assess the pathways of flow of contrast material between the three major retroperitoneal spaces. RESULTS: The caudal cone of perirenal fascia was uniformly patent. A narrow channel connected the two perirenal spaces in the midline; the posterior border of this channel abutted the anterior margins of the abdominal aorta and the inferior vena cava. The perirenal, anterior pararenal, and posterior pararenal spaces all communicated with the infrarenal space, which in turn connected with the extraperitoneal spaces in the pelvis. When large quantities of contrast medium are injected in the perirenal or pararenal spaces and the infrarenal space is filled, the infrarenal space may then serve as a conduit across the midline of the abdomen. The anterior pararenal space crossed the midline and had a distinct retrorenal extension but no intraperitoneal connection. The slender posterior pararenal space had an anterolateral extension en route to the prevesical space. CONCLUSION: Our findings show pathways and extensions of the perirenal, anterior pararenal, and posterior pararenal spaces that should be considered when assessing a variety of retroperitoneal diseases. Perinephric collections, such as hematomas and urinomas, have at least a potential conduit across the midline or into the pelvis. Our study explains how blood from a ruptured abdominal aortic aneurysm may enter either perinephric space. Anterior pararenal processes, such as pancreatitis or appendicitis, can extend into the pelvis or cross the midline, and posterior pararenal blood from trauma can also flow into the pelvis.

Comparison of 22-gauge Chiba and screw-tipped needles for cytologic diagnosis of malignancy in in vitro tumor specimens.

The relative effectiveness of two commonly used small-bore needles (22-gauge 30 degrees angle-tipped Chiba and 22-gauge screw-tipped needles) in fine-needle aspiration biopsies was compared prospectively in 39 abdominal or soft-tissue neoplasms freshly delivered to the authors' surgical pathology laboratory. With use of a "single-pass" standardized technique, cytologic sensitivity rates of 84% for the screw-tipped needles and 87% for the Chiba needles were obtained. No statistically significant difference in effectiveness was found between the two needles. While either needle is clearly acceptable for fine-needle aspiration, since the screw-tipped needle costs more than twice as much as the Chiba needle and is slightly more cumbersome to use, the Chiba needle appears to be preferable, at least initially, to the screw-tipped needle.

Transurethral prolapse of a simple ureterocele in a boy: case report.

Although simple ureteroceles are commonly encountered on urography, transurethal prolapse of the ureterocele in a male is an exceedingly rare complication. A fourth such case, with graphic, potentially confusing ultrasound and urographic findings, is presented and discussed.

Pitfalls in sonography of renal masses.

This paper reviews selected pitfalls in the use of ultrasound (US) for evaluating renal masses without attempting a comprehensive topic review.

ECG abnormalities during excretory urography: the effect of stress.

ECG alterations occurring during IV infusion of contrast agents have been well documented, although the specific causes of these alterations are unknown. Stress and anxiety have been considered important factors, but no prospective evaluation of their impact on ECG alterations has been reported. In order to separate ECG changes resulting from anxiety associated with the procedure itself from those caused by the contrast agent, ECG monitoring was done during IV urography, first when patients were given saline and then again during and after contrast infusion. In both circumstances, the patients were told that they were being given contrast material. One hundred fifty patients undergoing infusion excretory urography with meglumine diatrizoate were studied. Preliminary 12-lead ECGs identified those with initially normal (71) and abnormal (79) tracings. Lead II rhythm strip ECGs were then obtained at 1 and 3 min during a saline infusion and again during contrast infusion; final 12-lead ECGs were done after the contrast infusion. During contrast infusion, PR prolongation (greater than 0.02 sec) occurred in 44% of patients, a change in heart rate (greater than +/- 10 beats/min) occurred in 26%, and benign arrhythmias (premature atrial and ventricular contractions, less than 5/min) occurred in 9%. Saline alone caused no statistically significant ECG alterations (only a single instance of premature atrial contractions). The hypothesis that stress or anxiety may adversely affect ECG reactivity in IV urography is unproved. Although we do not offer proof that it cannot occur, we found no evidence in a study of 150 patients to confirm that stress is an important factor. Only the contrast agent, not saline, produced measurable ECG changes during urography.

Extracorporeal shock wave lithotripsy: impact on the radiology department of a stone treatment center.

Extracorporeal shock wave lithotripsy (ESWL) was performed on 925 patients (1,222 treatments) for 446 calyceal, 345 pelvic, 172 ureteral, and 108 staghorn calculi. ESWL necessitated 6.3 KUB and 1.2 renal ultrasound studies per treatment session. Intravenous urography was required in 6% of patients after ESWL. Percutaneous nephrostomy tube placement was performed by the radiologists in 10% of patients. Procedures related to nephrostomy tube placement included percutaneous nephrolithotripsy, tube changes, nephrostography, and stone fragment irrigations and retrievals. Staghorn calculi treatment with ESWL required the most procedures by radiologists (34% for partial staghorn and 56% for complete staghorn) compared with 3%, 8%, and 11% for calyceal, pelvic, and ureteral stones, respectively. In all, 8,478 radiologic examinations and procedures were performed pertaining to ESWL. This is approximately 35 studies per day. While this number may be high because it represents the early experience of the authors with ESWL, the impact on the radiology department can be substantial.

Nonutility of routine prone filming in adult urography.

The relative value of prone and supine filming in excretory urography was prospectively evaluated in 100 unselected, adult, high-dose urograms. The supine radiographs were superior or equal to prone radiographs in all cases. Significant findings were limited to the supine radiographs in six cases. Findings were seen on both supine and prone radiographs, but the supine radiograph was clearly better in nine cases. Major urinary structures were shown to better advantage on supine films, and the prone film was subject to radiographer error in a higher number of cases.

Ultrasonographic findings in mesenchymal hamartoma of the liver.

The ultrasonographic appearance of mesenchymal hepatic hamartoma in two infants is described. In both cases the echo patterns were predominantly anechoic, but showed evidence of trabeculation. The differential diagnosis of mesenchymal hepatic hamartoma is discussed.

Gallbladder wall thickening: ultrasonic findings.

Despite the commonplace pathologic occurrence of gallbladder wall thickening in cholecystitis, ultrasonic evaluation of the gallbladder wall has rarely proved useful. Three additional cases of clearly documented ultrasonically visible gallbladder wall thickening are presented to support recent contentions that this may be a new sign of gallbladder disease.