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Urology 05/2001; 57(4):604-10. · 2.43 Impact Factor
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Urology 05/2001; 57(4):599-603. · 2.43 Impact Factor
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ABSTRACT: The American Urological Association (AUA) convened the Best Practice Policy Panel on Asymptomatic Microscopic Hematuria to formulate policy statements and recommendations for the evaluation of asymptomatic microhematuria in adults. The recommended definition of microscopic hematuria is three or more red blood cells per high-power microscopic field in urinary sediment from two of three properly collected urinalysis specimens. This definition accounts for some degree of hematuria in normal patients, as well as the intermittent nature of hematuria in patients with urologic malignancies. Asymptomatic microscopic hematuria has causes ranging from minor findings that do not require treatment to highly significant, life-threatening lesions. Therefore, the AUA recommends that an appropriate renal or urologic evaluation be performed in all patients with asymptomatic microscopic hematuria who are at risk for urologic disease or primary renal disease. At this time, there is no consensus on when to test for microscopic hematuria in the primary care setting, and screening is not addressed in this report. However, the AUA report suggests that the patient's history and physical examination should help the physician decide whether testing is appropriate.
American family physician 04/2001; 63(6):1145-54. · 1.70 Impact Factor
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ABSTRACT: We evaluated the efficacy and safety of the Dornier compact lithotriptor for management of renal stones.
We administered 191 treatments to 169 patients with renal stones on 176 occasions with the patient under combined parental sedation and analgesia. The Dornier Compact lithotriptor is mobile and ultrasound guided, and uses an electromagnetic energy source.
A total of 22 patients required a second treatment (13%), 123 (72.8%) were stone-free, 26 (15.4%) had fragments less than 4 mm. large, 16 (9.5%) had stone fragments larger than 4 mm, and 4 (2.4%) required auxiliary therapy (treatment failures). The side effects were mostly mild to moderate, with nausea and/or vomiting reported in 26 patients (14%), colic or pain in 66 (39%), ureteral obstruction in 2, steinstrasse in 7 (4%) and fever in 1. Our clinical results indicate that extracorporeal shock wave lithotripsy was effective for treatment of stones in the kidney, with a low incidence of complications and adverse effects. The lithotriptor used is much smaller, less expensive and user friendly with no installation requirements, rendering it mobile.
The success rate with newer generation devices compares well with results obtained using other stationary and larger versions.
The Journal of Urology 04/1996; 155(3):834-8. · 3.75 Impact Factor
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ABSTRACT: We studied the effect of second generation lithotripsy on renal function.
We evaluated 42 patients with unilateral renal calculi by nuclear renography, serum creatinine levels, renal ultrasonography and plain radiographs.
There was no significant change in glomerular filtration rate at 1 or 3 months. Split function of the treated kidneys was lower at 1 month (mean 47.2%, p = 0.01) and 3 months (47.3%, p = 0.01) than before treatment (49.1%). A greater than 5% decrease in split function of the treated kidney occurred at 1 month in 6 patients (16.2%) and at 3 months in 3. Of the patients 23 (62.2%) were stone-free and 11 had residual fragments less than 4 mm., with a 19% retreatment rate for an overall success rate of 91.9%.
Newer generation lithotriptors may limit renal damage while permitting satisfactory treatment of renal calculi.
The Journal of Urology 10/1995; 154(3):947-50. · 3.75 Impact Factor
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ABSTRACT: Ureteroscopy (URS) and extracorporeal shockwave lithotripsy (SWL) battle for supremacy in the management distal ureteral calculi. In order to clarify issues surrounding this controversy, we created a decision tree modeling URS or SWL with literature-based probabilities and used as endpoints both cost and patient preferences. Ureteroscopy was more successful than single-session or multiple-session SWL, 92.1% v 74.3% or 84.5%, and had a lower retreatment/complication rate. Although initial SWL was only slightly more expensive than URS, $4,420 v $4,337, the difference increased when the additional costs of complications and retreatment were calculated, $6,745 v $5,555. Using values for an "average" patient, SWL was preferred to URS in terms of patient satisfaction. The most important factors distinguishing between URS and SWL were the success of treatment, the cost of initial therapy, and patient attitudes toward unplanned ancillary procedures and retreatment. Although no alteration of success rates and cost figures within reasonable ranges made URS less cost-effective than SWL, individual differences in patients' aversion for complications allowed URS to be preferred to SWL in some situations. Therefore, SWL is less cost-effective than URS and is not necessarily preferred by patients. The physician should be aware of the principal determinants of the choice between URS and SWL treatment of distal ureteral calculi.
Journal of Endourology 07/1995; 9(3):243-8. · 1.85 Impact Factor
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ABSTRACT: The role of cross-sectional pelvic imaging with computerized tomography or magnetic resonance imaging and fine needle aspiration in the assessment of pelvic lymph nodes in patients with prostate cancer is undefined. To address this issue we used formal decision analysis, comparing an imaging arm to a no imaging arm. Patient utility values were calculated, and test parameters and complication rates were extracted from the literature. Imaging was superior to no imaging only when the pretest probability of pelvic lymph node metastases was high. The most important parameter was the sensitivity of cross-sectional imaging for lymphadenopathy. When the sensitivity was 36%, which was the baseline figure derived from the literature, the probability of lymph node metastases required for imaging to be beneficial overall was 32%. We also performed a retrospective review of magnetic resonance imaging examinations at our institution in 174 patients with newly diagnosed prostate cancer and pathological confirmation of nodal status. The sensitivity for detecting nodal metastases was 25%. With this figure, the estimated probability of nodal metastases required to make imaging beneficial would be 45%, which is possible to achieve with highly selective clinical criteria. With a policy of imaging only in select patients the marginal cost is $794 per patient benefited (aborted radical prostatectomy because of nodal metastases detected with fine needle aspiration) compared to $50,661 per patient benefited if all patients are imaged. Thus, cross-sectional pelvic imaging before radical prostatectomy, solely for the purpose of detecting pelvic lymph node metastases, is not justified routinely. However, it is worthwhile on the basis of patient use values and cost-effectiveness in a select group of patients at high risk for nodal metastases.
The Journal of Urology 04/1995; 153(3 Pt 2):993-9. · 3.75 Impact Factor
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ABSTRACT: In order to compare the effects of intraperitoneal and extraperitoneal insufflation of CO2, we obtained blood gas measurements and chest radiographs in dogs during insufflation into three sites: the peritoneal cavity alone, the retroperitoneal space with communication into the peritoneal cavity, and the retroperitoneal space alone. The blood pH fell a mean of 0.11 +/- 0.03 and the PaCO2 rose a mean of 16.0 +/- 3.7 mm Hg when insufflation included the peritoneal cavity, whereas when insufflation was limited to the retroperitoneum, the pH fell a mean of 0.05 +/- 0.03 and the PaCO2 rose a mean of 7.5 +/- 2.8 mm Hg. Extrapleural thoracic dissection of gas was noted in one animal after insufflation limited to the retroperitoneal space. These findings confirm that there is significant absorption of CO2 from the peritoneal cavity during laparoscopy with CO2 insufflation, whether the pneumoperitoneum is primary or occurs secondary to retroperitoneal insufflation. If the insufflated gas is limited to the retroperitoneal space, however, the absorption of CO2 appears to be reduced in this animal model. The risk of thoracic dissection of gas may be greater during extraperitoneal insufflation than during intraperitoneal insufflation.
Journal of Endourology 03/1995; 9(1):63-6. · 1.85 Impact Factor
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ABSTRACT: A young, otherwise healthy man was hospitalized with clinical findings of acute retroperitoneal hemorrhage. Radiographic evaluation suggested a large bleeding renal mass that was thought to be renal cell carcinoma. Radical nephrectomy was performed after angio-embolization. Final pathological diagnosis was grade III transitional cell carcinoma of the renal pelvis invading the renal parenchyma. Distal ureterectomy was subsequently performed 12 days after nephrectomy. Preoperative or intraoperative diagnosis of transitional cell carcinoma would have spared our patient the morbidity of a delayed second procedure. Transitional cell carcinoma of the renal pelvis should be considered in the differential diagnosis of acute retroperitoneal hemorrhage.
The Journal of Urology 02/1995; 153(1):140-1. · 3.75 Impact Factor
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ABSTRACT: We analyzed retrospectively 127 percutaneous nephrolithotomies performed on 96 patients between 1986 and 1989 to estimate the average total blood loss from the procedure. Blood transfusions and a postoperative decrease in hemoglobin level were combined to estimate total blood loss. The average blood loss for uncomplicated 1-stage single puncture percutaneous nephrolithotomy was 2.8 gm./dl. hemoglobin. Factors potentially influencing blood loss were identified. Multiple punctures and/or renal pelvic perforation was associated with a 2-fold greater blood loss. Half of the expected blood loss occurred in patients with a preexisting nephrostomy tract. Calculus morphology, location, composition and length did not affect total blood loss, nor did the number of fragments or stone-containing calices. Other factors, such as puncture site, type of fascial dilation, hypertension, renal insufficiency, infection, previous open renal surgery or previous extracorporeal shock wave lithotripsy, also did not affect total estimated blood loss. During the study years the blood transfusion rate was 23% in all patients and 14% in those with a single puncture uncomplicated by renal pelvic perforation and without a mature nephrostomy tract. The only statistically significant risk factors influencing the likelihood of a blood transfusion were preoperative anemia and total blood loss. Although our current transfusion rate associated with percutaneous nephrolithotomy (4% in nonanemic patients from 1989 to 1992) is much lower, patients must be made aware of the likelihood of blood transfusion, and urologists should recognize the risk factors for blood loss and transfusion.
The Journal of Urology 01/1995; 152(6 Pt 1):1977-81. · 3.75 Impact Factor
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ABSTRACT: To evaluate compounds for the long-term inhibition of urinary calculi growth, we applied a newly developed in vitro assay to various metal-ligand complexes. The new experimental model--the preadsorbed calculi growth assay--was based upon the initiation of crystal growth in a metastable solution of calcium and oxalate with uniform granules derived from human renal calculi. Potential inhibitors were first absorbed onto the surface of the calculi granules, following which the loss of calcium from the seeded metastable solution was monitored as the indicator of calcium oxalate deposition. This assay allowed participation in the reaction by any matrix components present in the human calculi granules and limited the effect of the inhibitors to the calculi surface. Some complexes of metal ions with bisphosphonates had strong inhibitory effects, as opposed to citrate complexes which had minimal effect in this assay. Tin was the most potent metal ion, and pamidronate was the most potent bisphosphonate; together they slowed the growth of calculi granules to 9% of control. The inhibition by Tin-bisphosphonate complexes persisted despite a week of continual rinsing with a solution of sodium chloride and calcium. If the metal-bisphosphonate complexes are active in vivo as well, they might be considered for prophylaxis of calcium oxalate calculi or the prevention of regrowth of residual fragments following lithotripsy.
The Journal of Urology 12/1994; 152(5 Pt 1):1609-14. · 3.75 Impact Factor
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ABSTRACT: Using a new laparoscopic procedure, we investigated stimulation of the cavernous nerves to achieve erection in a canine model. The technique was developed during acute experiments in four dogs, following which, chronic studies (4- to 6-weeks survival after surgery) were undertaken in three dogs. A monopolar cuff electrode was inserted laparoscopically by a transperitoneal approach and placed around the cavernous nerve. The leads were brought out to the subcutaneous space, where they were attached to stimulation receivers that could be activated by an external radiofrequency transmitter. An intracavernous pressure elevation indicative of successful stimulation was obtained acutely in five of eight cavernous nerves in the four acute-study dogs and in four of six nerves in the three chronic-study dogs. The implanted equipment associated with four of six cavernous nerves failed mechanically in the chronic-study animals, such that only two receiver-electrode sites were intact at the time of sacrifice 4 to 6 weeks later. Transmitter-driven stimulation of one of these two sets produced an intracavernous pressure rise above 100 cm H2O. We present this technique as part of the continuing evolution of laparoscopy as both a research and a clinical tool. The present use of the laparoscopically implantable nerve-stimulating electrode is a new animal research tool and a potential first step in the human application of the technology.
Journal of Endourology 11/1994; 8(5):375-8. · 1.85 Impact Factor
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ABSTRACT: To determine the accuracy of the preoperative serum concentration of prostate-specific antigen (PSA) plus the Gleason pathology score of biopsy specimens in predicting the presence of disease in the pelvic lymph nodes in patients with prostate cancer.
The medical records of all patients treated for prostate cancer at eight medical centers from January 1988 to June 1993 were reviewed. There were 932 patients with newly diagnosed prostate cancer for whom all relevant data were available who had undergone pelvic lymphadenectomy with (n = 912) or without (n = 20) radical prostatectomy. The rate of false-negative predictions of metastases based on combined preoperative biopsy Gleason score and serum PSA concentration was analyzed. A multivariate logistic regression analysis was performed to assess the value of preoperative serum PSA and biopsy Gleason scores individually and in combination in predicting pelvic lymph node metastases.
The false-negative rate of metastases was 0% for preoperative PSA concentrations < or = 6 ng/mL and biopsy Gleason scores < or = 5 (n = 142) and 1.0% for PSA concentrations < or = 10 ng/mL and Gleason scores < or = 6 (n = 388). The 95% upper confidence limit for the rate of false negativity at this PSA cut-off level was 2.0%. A combination of preoperative serum PSA levels and biopsy Gleason scores provided the best prediction for the false-negative rates.
For patients with newly diagnosed prostate cancer who have biopsy Gleason scores < or = 6 and preoperative PSA concentrations < or = 10 ng/mL (42% of our series), a staging pelvic lymphadenectomy appears to be unnecessary. The substantial cost associated with both cross-sectional imaging and staging lymphadenectomy may therefore be avoidable in this group of patients.
Urology 11/1994; 44(4):519-24. · 2.43 Impact Factor
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The Journal of Urology 09/1994; 152(2 Pt 1):294-302. · 3.75 Impact Factor
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ABSTRACT: We compared prostate specific antigen (PSA) to PSA density for 3 clinical uses: detection of nonpalpable prostate cancer, staging of clinically localized prostate cancer and prediction of PSA detectability following radical prostatectomy. Of 153 men with normal digital rectal examinations undergoing prostate biopsy 25% had prostate cancer. Analysis of receiver operator characteristic curves demonstrated that PSA density predicted the outcome of biopsy significantly better than did PSA (p = 0.0013). Pathological examination of 155 radical prostatectomy specimens revealed that 56% had pathologically uncontained disease. There was no difference between the ability of PSA and PSA density to predict the pathological findings (p = 0.2379). PSA data more than 1 year postoperatively were available in 96 of the 155 prostatectomy patients. Of these men 41% had postoperative PSA levels of 0.1 ng/ml. or more. Preoperative PSA and PSA density values were almost identical in the ability to identify these patients (p = 0.6776). While PSA density is superior to PSA for the detection of prostate cancer in patients with a palpably normal prostate, it does not offer any improvement over PSA for staging of prostate cancer or for the prediction of PSA detectability after radical prostatectomy.
The Journal of Urology 08/1994; 152(1):120-3. · 3.75 Impact Factor
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ABSTRACT: The search for alternatives to carbon dioxide (CO2) for insufflation during laparoscopy has included the consideration of helium. Helium is attractive because it is noncombustible and has no pharmacologic effects. Unfortunately, it is also relatively insoluble in blood, which potentially could exacerbate a venous gas embolism. We performed rapid intravenous injections of CO2 and helium into 4 dogs in amounts ranging from 5 to 10 ml of gas per kilogram body weight. Recovery after CO2 injection always occurred within 1 min. In 4 of 6 instances, the helium injection was fatal. Our results confirm that helium is more lethal than CO2 when injected intravenously. This implies that the use of helium for insufflation during laparoscopy might place patients at greater risk for adverse effects should venous gas embolism occur.
Journal of laparoendoscopic surgery 07/1994; 4(3):173-7.
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ABSTRACT: To determine the impact of temporary vascular occlusion on patient outcome after surgery for renal trauma, we reviewed the records of 30 patients managed since 1977 whose injuries represented 17% of a total of 181 injuries in 175 patients. Reconstruction was judged to be adequate in 25 patients, while the remaining 5 underwent immediate nephrectomy. Compared with patients whose renal injuries did not require temporary occlusion, these 30 were more likely to have renovascular trauma, shock at presentation and higher transfusion requirements. Postoperatively, of 20 patients renal imaging (9) and radionuclide scanning (11) demonstrated preservation of significant renal parenchyma or function in 18 (90%). Although complications were more common in patients whose renal injuries required temporary vascular occlusion, only 2 were related to the renal injury or its method of repair (urinary extravasation in 1 patient and azotemia in 1 with bilateral injury). Temporary vascular occlusion can be performed expeditiously and safely, and may have an important role in preserving renal function. Our results support the routine use of early vascular control and the selective use of temporary vascular occlusion in renal injuries requiring exploration.
The Journal of Urology 06/1994; 151(5):1171-3. · 3.75 Impact Factor
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ABSTRACT: We investigated the use of bisphosphonates, analogs of pyrophosphate that bind to mineralized tissue, to image renal calculi in vivo. Twenty stone-bearing kidneys in 15 patients without urinary obstruction were studied. 99mTechnetium-methylene diphosphonate was injected intravenously followed by 20 mg of furosemide 4 hours later, and images were obtained by gamma counter for 30 minutes. Areas of increased uptake corresponded with the sites of calculi, and even small or radiolucent calculi were easily seen. Counts in the region of each kidney, the L4 vertebral body, and a background area were combined to calculate a scintigram index (SI) for each kidney. The mean SI of the stone-bearing kidneys was 4.8 +/- 3.5 v 1.3 +/- 0.4 for the normal kidneys. There was correlation of the SI with stone composition and size but not with radiographic density. After correction for size, the SI of stone-bearing kidneys remained significantly higher than the SI of normal kidneys, but the differences between calculi of different compositions were diminished. Nonetheless, high SI values were associated with soft types of calculi and low values with hard types. Future investigations will reveal if this association is constant and if there is any relation between bisphosphonate uptake and response to lithotripsy. The sensitivity of urolithoscintigraphy to image small or radiolucent calculi may make it an effective technique for the assessment of residual fragments after lithotripsy.
Journal of Endourology 05/1994; 8(2):133-7. · 1.85 Impact Factor
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ABSTRACT: New immunotherapeutic and chemotherapeutic regimens have altered the medical approach to metastatic renal cell carcinoma (RCC). Surgery for metastatic RCC needs to be reappraised in the context of these developments. We retrospectively examined the course of 25 patients with metastatic RCC who underwent nephrectomy or resection of renal fossa recurrences as an adjunct to intended systemic therapy. Four patients (16%) had complications and there was no perioperative mortality. Of 23 patients who had surgery first, 17 received subsequent systemic therapy and 2 experienced a response. Two patients underwent nephrectomy after achieving a partial response with systemic therapy. Overall, 3 patients (12%) are alive without detectable disease, 8 (32%) are alive with disease, and 14 (56%) are dead of disease, with a median survival of 23.5 months. Nephrectomy for metastatic renal cell carcinoma may be associated with less morbidity and mortality than previously reported. When initial nephrectomy is performed, most patients go on to receive systemic therapy. Within the context of a systemic treatment regimen, nephrectomy continues to play a role in the management of selected patients with metastatic RCC.
Journal of Surgical Oncology 02/1994; 55(1):7-13. · 2.10 Impact Factor
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ABSTRACT: Indications for laparoscopic pelvic lymphadenectomy prior to radical prostatectomy have not been established. Criteria to predict lymph node metastases were derived from the preoperative evaluations of 164 prostate cancer patients undergoing pelvic lymphadenectomy. Decision analysis was used to determine which criteria would be optimal indicators for laparoscopic pelvic lymphadenectomy prior to intended radical prostatectomy. Besides a digital rectal examination suggesting uncontained tumor, which was the best indication for laparoscopic pelvic lymphadenectomy, the most useful criteria were sonographic tumor volume > or = 3 cc and prostate-specific antigen (PSA) > or = 20 ng/mL. If either parameter was met, the sensitivity for identifying patients with pelvic lymph node metastases was 88 percent and the positive predictive value was 42 percent. When both were met, the sensitivity fell to 47 percent but the positive predictive value increased to 67 percent. A combination of Gleason biopsy score and PSA was the best criterion that was independent of transrectal ultrasonography. Using a PSA > or = 15 ng/mL for tumors with Gleason biopsy score > or = 7 or a PSA > or = 25 ng/mL for tumors with a Gleason biopsy score of 5-6 had a sensitivity of 71 percent and positive predictive value of 48 percent for identifying patients with pelvic lymph node metastases. In selecting patients for laparoscopic pelvic lymphadenectomy prior to radical retropubic prostatectomy, criteria with a positive predictive value greater than 39 percent maximize the utility of laparoscopic pelvic lymphadenectomy. Prior to radical perineal prostatectomy, laparoscopic pelvic lymphadenectomy will identify pelvic lymph node metastases that would otherwise be undetected by prostatectomy alone. The sensitivity of selection criteria, therefore, should be increased, as long as the positive predictive value remains above 20 percent.
Urology 01/1994; 42(6):680-8. · 2.43 Impact Factor
