Long-term outcome of caliceal diverticula following percutaneous endosurgical management.

PURPOSE: We review the morbidity and long-term outcome of percutaneous caliceal diverticulectomy and associated stone extraction. MATERIALS AND METHODS: Percutaneous caliceal diverticulectomy was performed in 19 women and 11 men (age range 20 to 58 years), of whom 26 had stones (all 15 mm. or less). The diverticula were located throughout the kidney, including the upper (11 patients), middle (15) and lower (4) calices. Percutaneous caliceal diverticulectomy included 28 direct and 2 indirect accesses (1 via a previously placed nephrostomy tract and 1 due to stones in other areas of the kidney). In all cases the stone was removed and the diverticular neck was incised or dilated. Fulguration of the diverticular walls was performed in 22 cases. Transdiverticular percutaneous renal and ureteral drainage was maintained from 2 to 7 days until a nephrostogram demonstrated no extravasation. RESULTS: The average operating room time and hospital stay were 171 minutes (range 75 to 330) and 4.1 days (range 2 to 7), respectively. Major complications occurred in 6.6% of the cases, requiring 1 blood transfusion and 1 chest tube placement, and minor complications occurred in 13.4%. There was no mortality. Followup for more than 1 year was available in 27 patients. Stone-free rate was 93% with obliteration of the diverticulum in 76% of patients. Overall, 85% of patients are asymptomatic at average followup of 3.5 years (range 1 to 7.3). CONCLUSIONS: Direct percutaneous endosurgical management provides a safe, efficacious and durable means of treating stone bearing caliceal diverticula, regardless of stone size or location of the diverticulum.

Bolus injection v drip infusion contrast administration for ureteral stone targeting during shockwave lithotripsy.

Intraoperative excretory urography may be used to facilitate stone targeting during in situ SWL for ureteral stones, precluding the need for ureteral catheter placement. We compared bolus injection with drip infusion urography for efficacy in stone localization. Twenty-seven patients with normal renal function and a solitary, difficult to visualize, radiopaque ureteral calculus were randomized to receive intravenous contrast by either bolus injection (N = 13) or drip infusion (N = 14). The bolus injection patients received an average of 74 mL of Conray 400 contrast over 1 minute; the drip infusion patients received an average of 92 mL of contrast over 15 minutes. After bolus injection, it took an average of 12 minutes to opacify the ureter compared with 14 minutes after drip infusion (P = 0.62). It took longer to initiate (5 minutes) and complete (6 minutes) treatment after drip infusion than after bolus injection (P = 0.28 and P = 0.16, respectively). Imaging time was significantly longer in the infusion group than in the bolus group (12 v 7 minutes; P = 0.04). Stone-free rates were similar in the two groups: 100% for the bolus group and 91% for the infusion group. No patient in either group experienced an adverse reaction to the contrast. Overall, the two methods of contrast administration were equally efficacious for stone targeting during SWL. However, bolus injection required lesser amounts of contrast, provided more rapid opacification of the ureter, and resulted in an overall shorter procedural time, although the only statistically significant differences were in imaging time and contrast volume.

Helical (spiral) CT angiography for identification of crossing vessels at the ureteropelvic junction.

OBJECTIVE: The purpose of this study was to determine the feasibility of imaging crossing vessels at the ureteropelvic junction (UPJ) with helical (spiral) CT angiography for planning surgical repair of symptomatic UPJ obstruction. SUBJECTS AND METHODS: Twenty-four consecutive patients with symptomatic UPJ obstruction were imaged with dual-phase, contrast-enhanced helical CT (collimation, 3 mm; pitch, 1.3-1.7; reconstruction interval, 2 mm; early phase, 20-42 sec; and delayed phase, 90-112 sec after initiation of IV contract material injection [125 ml of ioversol containing 320 mg of iodine per ml, delivered at 4-5 ml/sec]). All imaging data were viewed interactively on an imaging workstation. Prospective on-line interpretations were correlated with subsequent surgical and clinical findings at laparoscopy (n=3), open surgical repair (n=2), or ureteronephroscopic endopyelotomy (n=11). Vessels at the UPJ that were 2 mm or more in diameter were believed to be significant. Review of the transaxial images was performed to determine qualitatively the relative usefulness of the early versus the delayed phases for distinguishing arteries from veins. Multiplanar reformations also were retrospectively reviewed and compared with direct pyelograms to determine the accuracy with which the location of the UPJ and the proximal ureteral course were depicted with helical CT. RESULTS: Eleven of 24 (46%) patients collectively had 11 anterior and three posterior vessels (> or = 2 mm in diameter) crossing the UPJ on helical CT. Distinction between arteries and veins was significantly better on early-phase than on delayed-phase images (p=.01). Visualization of the UPJ and the proximal ureteral course was good or excellent for 18 (78%) of 23 patients for whom pyelograms were available, regardless of the presence of a ureteral stent (p>.05). Laparoscopy and open surgery findings were in agreement with helical CT angiograms for five of five patients. Uncomplicated endopyelotomy was performed for 11 patients in whom no significant vessels were seen posterior or posterolateral to the UPJ. CONCLUSION: Helical CT angiography can depict vessels crossing the UPJ and is valuable in planning surgical management.

Angiomyolipoma and renal cell carcinoma: US differentiation.

PURPOSE: To analyze whether shadowing and other ultrasound (US) features were helpful for distinguishing angiomyolipoma (AML) from renal cell carcinoma (RCC). MATERIALS AND METHODS: US images were reviewed of 49 patients with RCC and 35 patients with AML. Each tumor was evaluated for size, location, echogenicity, homogeneity, shadowing, hypoechoic rim, and intratumoral cysts. When available, computed tomographic (CT) scans of AMLs were analyzed for the amount of fat and soft tissue in each lesion. RESULTS: AMLs tended to be smaller and more frequently echogenic than RCCs, but statistically significant overlap occurred. Shadowing was seen in 12 (33%) AMLs but was not seen in RCCs. Hypoechoic rims and intratumoral cysts were seen only in RCCs (numbers were too small to perform further statistical analysis). CONCLUSION: In hyperechoic renal masses, the presence of shadowing, a hypoechoic rim, and intratumoral cysts are important findings that may help distinguish AML from RCC.

Corynebacterium urealyticum (CDC Group D2) associated with staghorn calculus: treatment by percutaneous debulking and chemolysis.

We report the formation of a staghorn calculus in a transplanted kidney caused by infection with a urea-splitting Corynebacterium group D2 organism. The stone was debulked percutaneously followed by intravenous vancomycin administration and urinary acidification with oral acetohydroxamic acid, leading to clearance of nearly all of the stone.

Determination of serum creatinine level before intravenous administration of iodinated contrast medium. A survey.

RATIONALE AND OBJECTIVES: To study the practice of obtaining serum creatinine before administering intravenous iodinated contrast medium and the costs associated with this practice. MATERIALS AND METHODS: In June 1993, a questionnaire was sent to 217 physicians who are members of the Society of Uroradiology or the Society of Computed Body Tomography/Magnetic Resonance. There were 149 respondents who completed a total of 70 questionnaires, providing a response rate of 69% (149/217). RESULTS: The percentage of institutions that always require a serum creatinine before administering intravenous contrast medium for excretory urography, body computed tomography, and head computed tomography was 13%, 20%, and 14%, respectively. In institutions where routine serum creatinine is not required, approximately 60% request a serum creatinine in either insulin-dependent or juvenile type 1 diabetes. The mean maximal acceptable time between the serum creatinine value and contrast administration is 29 days. It takes a mean of 69 minutes to get the results of a stat serum creatinine and costs a mean of 15 dollars for the test. In patients with no risk factors, the mean for the highest serum creatinine value at which respondents still gave contrast was 2.1 mg/dL; in patients with risk factors, the mean was 1.9 mg/dL. There was no correlation between the use of serum creatinine and the number of studies performed in the institution or the type of contrast used. CONCLUSIONS: The practice of requiring a pretest serum creatinine and its interpretation regarding the use of contrast media are quite variable. In view of this disparity in opinion, development and acceptance of a list of patients who are at increased risk for contrast-induced nephropathy may be desirable.

Extracorporeal shock-wave lithotripsy of middle ureteral stones: are ureteral stents necessary?

OBJECTIVES: To ascertain whether insertion of a ureteral stent improves the outcome of middle ureteral (overlying the pelvic bone) stones treated with extracorporeal shock-wave lithotripsy (ESWL). METHODS: Thirty-three patients with middle ureteral stones were treated with ESWL at our institution between October 1991 and October 1994. Twenty-six patients were available for follow-up; 14 patients were treated with stent bypass, 8 were treated in situ, and 4 patients were treated after percutaneous nephrostomy (PCN). All patients were treated initially on an unmodified Dornier HM-3, and all but 4 patients were treated in the prone position on a modified Stryker frame. Follow-up consisted of a plain abdominal radiograph, intravenous urogram, occasionally a retrograde urogram, and a telephone interview. RESULTS: The overall stone-free rate for ESWL alone was 73%, and the efficiency quotient was 69. The stone-free rates after a single treatment for the stent bypass, in situ, and PCN groups were 71%, 63%, and 75%, respectively. Overall, 4% of patients required retreatment, 19% of patients required an auxiliary procedure, and 8% of the patients required hospital or emergency room admissions for renal colic. For stones 10 mm or greater (9), stone-free rates after one treatment for the stent bypass, in situ, and PCN groups were 33%, 33%, and 67%, respectively; for stones less than 10 mm (17), success rates were 82%, 80%, and 100%, respectively. CONCLUSIONS: Pretreatment stinting provides no advantage over in situ ESWL for middle ureteral calculi (Fisher's exact test, P = 1.0). ESWL is a reasonable initial therapy for middle ureteral stones less than 10 mm.

The continuing competence needs of physicians: a survey of the medical specialty societies.

The exchange of information among the medical specialty boards regarding assessment protocols, testing outcomes, and validity studies has had an important effect on how individual boards choose to accomplish their goal of validating competence [1]. With many recertification programs firmly in place, the focus now shifts to the societies' responses to recertification and to the emerging needs of their members as they face the prospect of documenting continuing competence. How the specialty societies understand and complement the efforts of their certifying boards and what types of programs they are developing in response to the continuing competence and recertification needs of their individual members is information that has not, to date, been collected or reported. The Task Force on Continuing Competence of the American College of Radiology developed a questionnaire to gather data on recertification and on the support programs developed by professional societies for recertification and continuing competence.

The extraperitoneal approach and subcutaneous emphysema are associated with greater absorption of carbon dioxide during laparoscopic renal surgery.

PURPOSE: We investigated the association of carbon dioxide absorption with the approach (transperitoneal versus extraperitoneal) and other factors during laparoscopy. MATERIALS AND METHODS: Carbon dioxide elimination during laparoscopic renal surgery was retrospectively calculated in 63 patients. RESULTS: Carbon dioxide elimination increased with time. Multiple factorial analysis revealed that subcutaneous emphysema and the extraperitoneal approach were independently associated with a greater increase in carbon dioxide elimination. Pneumothorax and pneumomediastinum were more common during extraperitoneal procedures. CONCLUSIONS: Carbon dioxide absorption during laparoscopic renal surgery increases with time, and is greatest in patients treated through an extraperitoneal approach and in those with subcutaneous emphysema. Nonetheless, with attentive ventilatory management adverse sequelae of hypercapnia can be avoided.

Carbon dioxide absorption during laparoscopic pelvic operation.

BACKGROUND: Several factors may influence the degree of carbon dioxide (CO2) absorption during laparoscopy. Hypercapnia as a result of excessive CO2 absorption may have adverse clinical effects. STUDY DESIGN: To identify factors associated with increased CO2 absorption, we retrospectively calculated the CO2 elimination in 65 adult patients who underwent operative pelvic laparoscopy. Increases in CO2 elimination were assumed to be indicative of CO2 absorption. The most commonly performed procedures were bladder neck suspension and pelvic lymphadenectomy. The median insufflation time was 165 minutes. An extraperitoneal approach was taken in 32 percent of the patients. RESULTS: Of patients evaluated with postoperative roentgenograms of the chest, 35 percent had subcutaneous emphysema and 9 percent had pneumomediastinum with or without pneumothorax. Multiple factorial analysis of the variance revealed that the extraperitoneal approach, development of subcutaneous emphysema, and increased duration of insufflation were independently associated with a greater increase in peak CO2 elimination. Insufflation time and subcutaneous emphysema had stronger effects in the extraperitoneal group. CONCLUSIONS: The risk factors for hypercapnia can be identified. Careful consideration of the patient's ability to tolerate hypercapnia should be made when planning extraperitoneal laparoscopy, especially if the procedure is likely to be prolonged. The clinical development of subcutaneous emphysema should alert the surgeon to the possibility of subsequent hypercapnia.

Dynamic incremental CT: effect of volume and concentration of contrast material and patient weight on hepatic enhancement.

PURPOSE: To develop an individualized approach to the intravenous administration of contrast material for hepatic computed tomography (CT). MATERIALS AND METHODS: Two hundred patients were randomized into eight protocols. Each group received different volumes and concentrations of contrast material. For each protocol, maximum hepatic enhancement (MHE) was calculated, with an adjustment for iodine dose and patient weight. The contrast enhancement index (CEI) and optimum scanning interval were calculated for hepatic enhancement thresholds of 10-60 HU. RESULTS: The MHE calculated as a function of patient weight was 96 HU +/- 19 per gram of iodine per kilogram of body weight. CEIs obtained with a contrast material concentration of 240 mg of iodine per milliliter were inferior to those obtained with a concentration of 320 or 350 mg I/mL. At low enhancement thresholds, the volume of contrast material had a more important effect than the concentration on CEI and optimum scanning interval; at high thresholds, concentration had a more important effect. CONCLUSION: For a patient of known weight, one can calculate the iodine dose needed to provide a desired level of hepatic enhancement. Use of a contrast material with a concentration of 240 mg L/mL is not recommended for dynamic incremental hepatic CT, except in small patients (eg, those weighing less than 73 kg).

Adrenal involvement from renal cell carcinoma: predictive value of computerized tomography.

Although adrenal involvement from renal cell carcinoma is rare, removal of the adrenal during radical nephrectomy continues to be standard practice. To assess the actual need for adrenalectomy, we elected to evaluate whether malignant involvement of the adrenal gland could be reliably diagnosed preoperatively by a computerized tomogram (CT) of the abdomen. A blinded retrospective review of preoperative abdominal CT in 157 patients with renal cancer revealed an abnormality of the ipsilateral adrenal gland in 38. Histopathology confirmed malignant involvement of the adrenal in 10 patients. Significantly, all 119 adrenal glands judged to be normal on the preoperative CT were confirmed to be uninvolved by the renal cancer on histopathological study. We conclude that abdominal CT is reliable in the preoperative evaluation of the ipsilateral adrenal gland and assessment of its noninvolvement with renal carcinoma. In such cases adrenal sparing nephrectomy may be considered (76% of our patients). None of these 119 patients had either macroscopic or microscopic adrenal involvement. When the adrenal is not identified, displaced or enlarged on CT (24% of our patients) adrenalectomy should be routinely performed as part of radical nephrectomy. Even in this select group adrenal involvement was present in only 26% of the cases.

Chest radiography in patients with early stage prostatic carcinoma. Effect on treatment planning and cost analysis.

STUDY OBJECTIVE: An evaluation of the impact of routine preoperative chest radiographs was retrospectively undertaken in a pilot group of 292 patients with prostatic carcinoma who were part of a prospective study of prostate specific antigen screening for prostate carcinoma. DESIGN: Retrospective. SETTING: Hospital-based outpatients. PATIENTS AND PARTICIPANTS: A cost-effectiveness model was used to assess the value of routine chest radiography in this patient population. Chest radiography findings were categorized into four groups based on follow-up and impact. MEASUREMENTS AND RESULTS: Forty-three patients (15 percent) had a total of 45 positive findings on their chest radiographs. No patient had intrathoracic metastases from prostatic carcinoma. Only two patients (both with unsuspected second neoplasms) had findings that impacted on their treatment and one avoided retropubic radical prostatectomy. Total cost was $2,000 (based on Medicare reimbursement), or $14,000 (based on physician and hospital charges). CONCLUSION: Although benefit is small in terms of number of patients affected, clinical impact, in the two patients with significant findings, was great. Although cost-effectiveness cannot be confirmed on the basis of this series, further evaluation of its utility for this application should be undertaken.

Massive ascites and pleural effusions associated with endometriosis.

We report a case of the unusual presentation of endometriosis causing ascites and pleural effusions subsequently confirmed at laparoscopy. This uncommon occurrence should be considered in a woman of childbearing age with appropriate clinical history, massive ascites, and cystic pelvic masses.