Thermal ablation of the gallbladder.

Gallbladder ablation by means of injection of hot contrast medium was attempted in 13 dogs. Room temperature contrast medium was injected into the gallbladders of two additional dogs (controls). After midline laparotomy was performed to expose the gallbladder, temperature probes were placed in the liver adjacent to the gallbladder, and on the surface and in the lumen of the gallbladder. A 7-F catheter with multiple side holes was placed into the gallbladder. The cystic duct was clamped during the procedure. After injection of boiling contrast medium, the mean temperature in the gallbladder lumen was 80 degrees C; in the adjacent liver, 43.5 degrees C; and on the gallbladder surface, 45.8 degrees C. After the procedure, the cystic duct was unclamped, temperature probes and catheter were removed, and the laparotomy was closed in standard fashion. In the hot contrast medium group, one dog each was sacrificed at 2, 4, 8, and 12 weeks, and at 6 months. Six animals were sacrificed at 1 year. The gallbladder was completely ablated in 11 of 13 animals in the hot contrast medium group. One dog was sacrificed at 8 days because of bile leakage, and another was sacrificed at 17 days because of gallbladder rupture. The two control animals were sacrificed at 12 and 13 weeks, and their gallbladders were normal at that time.

Ureteral pseudodiverticula: frequent association with uroepithelial malignancy.

Ureteral pseudodiverticula are tiny outpouchings usually seen as incidental findings on retrograde urography during routine work-up for common urinary tract disorders. We report 37 patients with ureteral pseudodiverticula, of whom 17 (46%) had associated uroepithelial malignancy. Ureteral pseudodiverticula were diagnosed in all patients on excretory or retrograde urography as an incidental finding during evaluation for a variety of urologic symptoms and signs. All patients were assessed with urinalysis, urine culture, cystoscopy, and when indicated, ureteroscopy. Diagnosis of transitional cell carcinoma was made by surgery or endoscopic biopsy in 16 patients and squamous cell carcinoma in one. In nine patients with radiographs showing ureteral pseudodiverticula and a urinary tract filling defect (usually in the bladder), 78% of the cases were proved malignant. In six patients with ureteral pseudodiverticula and a stricture in the ureter or renal collecting system, 67% of the cases were proved malignant. Of the patients with tumor, 53% had a single ureteral pseudodiverticulum. In two cases, the pseudodiverticula antedated the diagnosis of malignancy by 2 and 4 years, respectively. Our experience suggests that the association between ureteral pseudodiverticula and uroepithelial malignancy may be more common than previously assumed, approaching 50%. Even a single ureteral pseudodiverticulum should be regarded as a serious marker for potential malignancy, antedating cancer by 2-10 years, and such patients should be closely followed up. The coexistence of ureteral pseudodiverticula and a stricture or filling defect in the urinary tract is highly suggestive that a tumor is present.

Atheroablation with the Kensey catheter: a pathologic study.

The mode of action of the Kensey catheter, a new atheroablation device, was investigated. Fresh above-the-knee amputated legs were used for recanalization of the superficial femoral artery. The variables used were identical to those of clinical trials, including a rotational speed of 50,000 rpm and an injection rate of 40 mL/min. The debris produced by the catheter was studied cytologically, and the arterial segments were examined histologically. The particle size in the debris ranged from 1 to 2,000 microns. The softer plaques produced a fine fibrin dust background with long strips of intima ranging from 10 to 2,000 microns. Complicated calcified plaques produced larger background material (10-120 microns) but smaller strips of intima (50-800 microns). Dissections and perforations occurred. Some of the debris produced by the atheroablation process was used to embolize a canine heart and kidney. Small focal infarctions were found in the heart, and large and multiple infarcts were seen in the kidney. In clinical studies the debris appears to be tolerated in the lower extremities. Its safety in the kidney and heart are questioned.

The pathology of ureteral pseudodiverticulosis.

We studied 200 postmortem ureters from 100 adult men to test the hypotheses that ureteral pseudodiverticula (UPD) are more prevalent than clinically recognized, that UPD are secondary to chronic inflammations, and that they are associated with uroepithelial neoplasm. The ureters were inflated with 10% formaldehyde and fixed for 24 hours. One hundred sixteen ureters were drained and refilled with 25% diatrizoate sodium meglumine and radiographed before gross and microscopic pathologic examination. No radiographs of the remaining 84 ureters were obtained. UPD were identified pathologically in 11%. None of these patients had a history of upper urinary tract disease. UPD were smaller than those reported clinically and invariably were associated with focal microscopic ureteritis cystica and glandularis in ureters otherwise free of histologic abnormality. UPD displayed mild benign mucosal hyperplasia with invagination in the subepithelial connective tissue as well as impression and sometimes thinning of the muscularis propria but without penetration. No mucosal atypia or malignancy was seen. We postulate that UPD represent a proliferative response to focal inflammation resulting in intramural invasion producing elevation and thinning of the ureteral wall. Continued focal inflammation may be sustained by local urine stasis. Enlargement to clinically detectable size may be enhanced by more generalized disease such as clinical infection, stone, or obstruction.

Ureteral pseudodiverticulosis.

There have been few reported cases of ureteral diverticula less than 4 mm in diameter; these are best described as pseudodiverticula based on their appearance in specimens obtained for pathologic study. An additional 23 patients are reported, 15 of whom were examined by urinalysis, urine culture, cystoscopy, and cytologic studies of the urine. Cytologic findings are of interest because of previous reports suggesting an association between ureteral diverticula and transitional cell carcinoma in the urinary tract. Hematuria, transitional cell carcinoma, and benign prostatic hyperplasia were the most common presenting conditions. Infection was found in only three. Diverticula were multiple in 91%, bilateral in 69%, and were predominantly upper and midureteral in location. Urine cytologic studies failed to detect early uroepithelial malignancy, but nonspecific cellular atypia and an association with malignancy in 30% of these patients suggests that close follow-up of patients with ureteral pseudodiverticulosis is prudent.

Hemangiopericytoma of the tongue: report of case.

A case of hemangiopericytoma of the tongue is reported. A comprehensive literature review regarding hemangiopericytoma of the tongue has been presented. Only ten cases of hemangiopericytoma of the tongue have been reported in the literature, including the present case, a 29-year-old male.

The use of fresh-frozen tissue in diagnostic transmission electron microscopy.

We have examined the effects of freezing on fresh pathologic human tissue specimens with regard to the fine structural preservation of various organelles that can be of diagnostic importance. Specimens included in this study were frozen either in the cryostat (-20 degrees C) or by quenching in isopentane cooled by liquid nitrogen (-115 degrees C). The results indicate that fresh-frozen tissue that is subsequently fixed and processed for transmission electron microscopy (TEM) provides ultrastructural information that is very nearly equal to that of conventionally processed specimens. Additionally, we performed identical freezing experiments using animal (rat) tissue in order to ensure that the results we obtained using a rather limited number of human specimens were valid. The outcome of these animal experiments thoroughly supports our observations using human pathologic tissue. We believe an appreciation of the fact that fresh-frozen tissue is suitable for TEM examination may become a very valuable resource in the surgical pathology laboratory.

Normal gallbladder scintigraphy in acute cholecystitis.

Normal gallbladder scintigraphy occurs in 2 to 5% of reported patients with acute cholecystitis. Gallbladder visualization is found in patients with acalculous cholecystitis and in those with recent relief of cystic duct obstruction but persistence of inflammation. A patient is reported who had clinical and pathologic findings of acute cholecystitis but normal gallbladder visualization. This reemphasizes that the diagnosis of acute cholecystitis cannot be excluded by normal gallbladder scintigraphy.

Electron microscopic identification of the colorectal origins of tumor cells in pleural fluid.

Cellular material from metastatic rectal and lung adenocarcinomas was recovered from pleural and pericardial fluids, respectively. It was examined by electron microscopy (EM) to determine if certain ultrastructural features, which are primarily prominent in colorectal adenocarcinomas, were maintained in the tumor cells in metastatic fluid. These features include the presence of microvilli with dense microfilamentous cores that extend deeply into the apical cytoplasm (cytoplasmic rootlets) and an abundance of glycocalyceal bodies. It was found that tumor cells from the patient with a primary rectal adenocarcinoma exhibited these critical distinguishing characteristics. The cells from the lung adenocarcinoma, while containing many well-developed microvilli, did not possess cytoplasmic rootlets or glycocalyceal bodies. In addition, and possibly of more diagnostic significance, is the observation that the presence of microvilli and cytoplasmic rootlets remained evident in tissue pieces and cell blocks initially processed in paraffin and then reembedded for EM.