Tips and tricks of laparoscopic partial nephrectomy.

The field of urology has embraced minimally invasive surgical procedures, from endoscopic to laparoscopic to robotic assisted surgery. As these surgical techniques are applied to renal cancer, the oncological outcomes need to be compared to more traditional open surgery. Laparoscopic partial nephrectomy emulates the open surgical technique and has become an alternative to open surgery at many academic centers. Still its wide spread adoption has been limited by the challenges of renal mass extirpation and renal reconstruction in a timely fashion to limit renal ischemia. The following review is designed to assist the urologic surgeon in performing a successful laparoscopic partial nephrectomy by detailing the "tips and tricks" of the procedure.

Metabolic Syndrome and Nephrolithiasis Risk: Should the Medical Management of Nephrolithiasis Include the Treatment of Metabolic Syndrome?

This article reviews the relationship between metabolic syndrome (MetS) and nephrolithiasis, as well as the clinical implications for patients with this dual diagnosis. MetS, estimated to affect 25% of adults in the United States, is associated with a fivefold increase in the risk of developing diabetes, a doubling of the risk of acquiring cardiovascular disease, and an increase in overall mortality. Defined as a syndrome, MetS is recognized clinically by numerous constitutive traits, including abdominal obesity, hypertension, dyslipidemia (elevated triglycerides, low high-density lipoprotein cholesterol), and hyperglycemia. Urologic complications of MetS include a 30% higher risk of nephrolithiasis, with an increased percentage of uric acid nephrolithiasis in the setting of hyperuricemia, hyperuricosuria, low urine pH, and low urinary volume. Current American Urological Association and European Association of Urology guidelines suggest investigating the etiology of nephrolithiasis in affected individuals; however, there is no specific goal of treating MetS as part of the medical management. Weight loss and exercise, the main lifestyle treatments of MetS, counter abdominal obesity and insulin resistance and reduce the incidence of cardiovascular events and the development of diabetes. These recommendations may offer a beneficial adjunctive treatment option for nephrolithiasis complicated by MetS. Although definitive therapeutic recommendations must await further studies, it seems both reasonable and justifiable for the urologist, as part of a multidisciplinary team, to recommend these important lifestyle changes to patients with both conditions. These recommendations should accompany the currently accepted management of nephrolithiasis.

Laparoscopic enterolysis and placement of an intestinal sling before radiation therapy for the treatment of prostate cancer.

We present an interesting application of laparoscopy in a man who was otherwise not a candidate for radiotherapy because of an adherent loop of small bowel in the proposed treatment field. Laparoscopic enterolysis was performed and the involved segment was displaced out of the pelvis; a synthetic mesh was placed to serve as a sling to prevent caudal migration back into the pelvis. The patient had a rapid recovery and subsequently completed a full course of radiotherapy. The experienced laparoscopist may find this a good alternative to open surgery in patients with a fixed loop of small bowel who require radiation therapy for pelvic malignancies.

Protease inhibitor-induced urolithiasis.

OBJECTIVES: To describe protease inhibitor-induced urinary stone disease in patients with human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS) who are taking indinavir sulfate (Crixivan), a protease inhibitor, for the treatment of AIDS. METHODS: Patients with HIV/AIDS and symptomatic renal colic temporally related to the initiation of indinavir sulfate therapy were prospectively identified. Seven patients (mean age 42 years; all men) with HIV and renal colic who were taking indinavir were identified. Retrospective chart reviews and patient interviews were performed. RESULTS: Indinavir therapy averaged 5.7 months prior to presentation with renal colic. All patients had microscopic hematuria. One patient presented with acute azotemia from bilateral urinary obstruction. Six patients had no history of urinary stones prior to initiating indinavir. The median number of symptomatic urinary stone episodes after initiating indinavir was two stones per patient. All patients had moderate- to high-grade urinary obstruction from radiolucent calculi. Abdominal computed tomography (CT) demonstrated hydronephrosis without urinary calcifications. Three patients spontaneously passed stones and 4 required intervention. Yellow debris and/or brown matrix-like material was seen endoscopically. Stone analysis revealed pure protease inhibitor. Six patients (86%) eventually discontinued protease inhibitor therapy. CONCLUSIONS: Protease inhibitor-induced urinary stones are radiolucent and can cause high-grade ureteral obstruction. Protease inhibitor-induced urinary stones were not identified on unenhanced abdominal CT scans. The radiolucent gelatinous nature of such stones makes lithotripsy a poor choice of treatment. Ureteral stenting may allow spontaneous stone passage if symptomatic obstruction occurs. Urologists may encounter a greater number of patients with symptomatic protease inhibitor-induced urinary calculi as these medications become more popular.

Mini-percutaneous nephrolithotomy.

Standard percutaneous nephrolithotomy is highly effective for the removal of renal calculi. However, significant morbidity has been associated with this procedure. Consequently, many urologists inappropriately defer to a less effective procedure to reduce patient morbidity. This practice may increase the total number of procedures needed for treatment and result in a substantial increase in health care costs. Mini-percutaneous nephrolithotomy using a 13F ureteroscopy sheath is described to reduce the morbidity associated with standard percutaneous nephrolithotomy while maintaining its efficiency and effectiveness for stone removal. The indications and technique for mini-percutaneous nephrolithotomy and our results are summarized.

Use of rigid hysteroscope for extraction of foreign bodies embedded in lower urinary tract.

PURPOSE: To introduce the use of the 20F rigid hysteroscope in urologic procedures. MATERIALS AND METHODS: The 20F hysteroscope was used to remove deeply embedded foreign bodies from the lower urinary tract of three patients in whom previous attempts with standard cystoscopic equipment were unsuccessful. RESULTS: In all three cases, the hysteroscope easily passed into the urethra and with the use of rigid instruments was able to remove the foreign bodies without complication. CONCLUSION: Situations may arise when the removal of embedded foreign bodies is not possible with standard cystoscopic equipment. The hysteroscope, which is available in most operating rooms, was able to extirpate even deeply embedded foreign bodies.

New technique in managing ureteropelvic junction obstruction: percutaneous endoscopic pyeloplasty.

Endopyelotomy is currently advocated for management of the obstructed ureteropelvic junction (UPJ). Healing of the stented UPJ occurs by secondary intention. Regardless of the method employed, success rates approach 85%. In order to increase the rate of success, we have devised a method of performing endopyelotomy in conjunction with endoscopic suturing of the incised UPJ. Two methods were developed to allow for the placement of a single absorbable monofilament suture. In the first method, endopyelotomy is carried out in the standard antegrade manner, and endoscopic suturing is performed with the use of a second retroperitoneal access sheath at the UPJ. In the second method, endoscopic placement of the suture is carried out through the standard renal access sheath, with suturing performed via the nephroscope. We have performed endoscopic pyeloplasty in eight patients. With a mean follow-up of 12 months, the procedure was successful in seven of these patients. Endoscopic suturing of the UPJ is technically demanding, but once sufficient expertise is gained, it may be utilized for immediate tissue coaptation, possibly decreasing urinary extravasation and, it is hoped, maximizing the caliber of the UPJ.

13-year survival comparison of percutaneous and open nephroureterectomy approaches for management of transitional cell carcinoma of renal collecting system: equivalent outcomes.

BACKGROUND AND OBJECTIVE: Transitional cell carcinoma (TCC) of the renal collecting system traditionally has been managed by open nephroureterectomy with en bloc resection of a bladder cuff. However, for a select patient population with a solitary kidney or bilateral disease, the morbidity and mortality associated with chronic renal insufficiency and dialysis is deterring. In these situations, a more conservative approach such as antegrade percutaneous resection should be considered. The long-term disease-free outcome of percutaneous management in comparison with open nephroureterectomy has not been previously reported. We evaluated our experience with two surgical approaches to treat upper tract TCC: percutaneous resection and nephroureterectomy/nephrectomy to assess the clinical efficacy of these surgical modalities. PATIENTS AND METHODS: We retrospectively identified 162 patients who had clinically localized TCC of the upper urinary tract. Records were reviewed to identify those with 13-year follow-up (N = 110) in respect to tumor grade, stage, disease-free status, length of cancer-specific survival, and overall survival. Statistical analysis of the results of open nephroureterectomy/nephrectomy (N = 60) and percutaneous resection (N = 50) was performed using Kaplan-Meier survival curves and Student's t-test. RESULTS: All patients had disease in clinical stage Ta through T3. During a mean follow-up of 46.6 (range 6-150) months, grade 1 disease demonstrated little invasive potential. Of the disease-specific deaths, 60% (17/26) were of patients with grade 3 lesions, with a mean cancer survival period of 15.2 months after the initial procedure. Disease-specific survival rates after open and percutaneous approaches for grade 2 disease were 53.8 and 53.3 months, respectively (P > 0.05). CONCLUSIONS: Tumor grade appeared to be the most important prognostic indicator in patients with renal TCC regardless of the surgical approach. Grade 3 tumors were more aggressive, presenting in an advanced stage with invasion, and recurrences were usually associated with metastasis. In this population, nephroureterectomy is warranted if the patient is a surgical candidate. The percutaneous option for grade 1 or 2 disease may be extended beyond the population with solitary kidneys and a risk of chronic renal failure to be offered to healthy individuals with normal contralateral kidneys who are willing to abide by a strict and lengthy follow-up.

Model of human transitional cell carcinoma: tumor xenografts in upper urinary tract of nude rat.

An in vivo model for the study of human transitional cell carcinoma (TCC) in the urinary tract is desirable. Orthotopic xenografts are useful in order to approximate better the behavior of human tumor cells in situ. Prior models have been described in the urinary bladder of the nude mouse and rat. We have developed the first model of implantation of human TCC in the upper urinary tract of an experimental animal. The kidneys of homozygous nude rats 4 weeks of age were inoculated with 1-5 x 10(6) cells of the RT4 well-differentiated papillary human TCC line through bilateral flank incisions, with transparenchymal injection of tumor cells into either the collecting system (renal pelvis) or the parenchyma. The overall implantation rate was 92% (54/59 kidneys). However, implantation into the collecting system occurred in only 45% (18/45) of the group. Ligation of the ureter prior to inoculation to produce urine stasis improved the mucosal implantation rate. Despite suspect urine cytology findings in the renal pelvis injection group, no distal seeding of the urinary tract was seen. Intraparenchymal tumor growth was less differentiated and had a higher fraction of mitotic cells than mucosal tumors. Vascular and lymphatic invasion were commonly seen; however, distant metastasis was not observed. This model will prove useful in determining the role of seeding in recurrent disease and in developing less invasive modalities for the treatment of upper tract TCC.

Endourologic management of complications in renal allografts.

Because of the altered anatomy, the presence of immunosuppression, the possibility of graft rejection, and the serious implications of a problem involving a solitary kidney, the transplanted kidney presents unique challenges in the diagnosis and treatment of urologic complications. Historically, the mortality rate in these patients has been as high as 68%, and as many as 15% of the allografts have been lost. Today, endourologic procedures are used for prompt diagnosis, temporization, and even definitive management of many urologic complications, and many patients and allografts are being saved. The authors review present techniques and suggest others that may be available in the future.

Familial calcium stone disease: TaqI polymorphism and the vitamin D receptor.

BACKGROUND AND OBJECTIVE: Calcium nephrolithiasis has a strong familial component. However, to date, no specific genetic abnormality has been identified. Allelic variation in the vitamin D receptor (VDR) gene has been suggested as a partial explanation of differential calcium absorption or excretion in these patients. Polymorphism of this gene has been associated with altered vitamin D activity and has been implicated in osteoporosis and prostate cancer. We propose that a similar association may be found between familial hypercalciuric stone disease and the VDR. SUBJECTS AND METHODS: Genomic DNA was isolated from 37 controls and 19 patients with hypercalciuria (> 250 mg/24 hours) and a family history of nephrolithiasis. A 740-basepair segment of the VDR gene was amplified by polymerase chain reaction, digested with TaqI endonuclease, and resolved by gel electrophoresis. Alleles were classified as "T" if only one TaqI site was present and "t" if two were present. A simplified strength of family history score (FHS) was computed by adding 2 and 1 points, respectively, for each first- and second-degree relative affected by stone disease. RESULTS: No difference in allelic or genotypic frequencies between the study and control groups was present. In the stone group, a significant association was found between the strength of the family history and the TT genotype. Patients with this genotype had an average FHS of 4.0, whereas the mean FHS for the Tt and tt genotypes was 2.0 and 1.8, respectively (P < 0.05). Nonsignificant trends of the TT genotype toward a higher number of stone episodes (19 v 13 and 3) and higher 24-hour urine calcium excretion (408 v 297 and 353 mg) were also noted in the study group. CONCLUSION: The results suggest that the TT genotype is associated with more aggressive stone disease, both within families and with respect to recurrence. Quantifying the risk of calcium stone disease through DNA markers has potential application in determining the risk of a patient's family members for nephrolithiasis or a patient's risk of recurrence. This information may have therapeutic implications with regard to the rigor of medical therapy and frequency of follow-up.

Effect of time delay on surgical performance during telesurgical manipulation.

BACKGROUND: Telementoring allows a less experienced surgeon to benefit from an expert surgical consultation, reducing cost, travel, and the learning curve associated with new procedures. However, there are several technical limitations that affect practical applications. One potentially serious problem is the time delay that occurs any time data are transferred across long distances. To date, the effect of time delay on surgical performance has not been studied. MATERIALS AND METHODS: A two-phase trial was designed to examine the effect of time delay on surgical performance. In the first phase, a series of tasks was performed, and the numbers of robotic movements required for completion was counted. Programmed incremental time delays were made in audiovisual acquisition and robotic controls. The number of errors made while performing each task at various time delay intervals was noted. In the second phase, a remote surgeon in Baltimore performed the tasks 9000 miles away in Singapore. The number of errors made was recorded. RESULTS: As the time delay increased, the number of operator errors increased. The accuracy needed to perform remote robotic procedures was diminished as the time delay increased. A learning curve did exist for each task, but as the time delay interval increased, it took longer to complete the task. CONCLUSIONS: Time delay does affect surgical performance. There is an acceptable delay of <700 msec in which surgeons can compensate for this phenomenon. Clinical studies will be needed to evaluate the true impact of time delay.

Prospective double-blind study of effect of ketorolac administration after laparoscopic urologic surgery.

BACKGROUND AND PURPOSE: To decrease postoperative dependence on narcotics for analgesia, we have evaluated ketorolac as an adjunct to perioperative pain control in patients undergoing laparoscopic urologic surgery. PATIENTS AND METHODS: Sixty-five patients (34 male, 31 female) were randomized to receive either ketorolac tromethamine (15-30 mg IV q 6 h) or placebo prior to laparoscopic surgery. Patient-controlled analgesia in the form of morphine sulfate was provided. Operative factors such as the type of surgery, operative time, and estimated blood loss were recorded. Postoperative factors such as analog pain score (range 0-10), narcotic usage, and length of stay were evaluated. RESULTS: Fifty-five patients completed the study. The average pain score was 2.2 and 4.5 for the ketorolac and placebo groups, respectively (P < 0.005). The mean amounts of total morphine used were 39.2 mg (ketorolac) and 62.5 mg (placebo) (P = 0.077). The length of stay was not significantly different in the ketorolac (2.5 days) and placebo (2.6 days) groups (P = 0.74). Operative times (P = 0.21) and estimated blood loss (P = 0.60) were not significantly different in the two groups. Ketorolac did not adversely affect renal function; serum creatinine changes were not significantly different from those in the patients receiving placebo (P = 0.50). Laparoscopic pyeloplasty necessitated more narcotic analgesia than did other laparoscopic procedures (P = 0.05). CONCLUSION: Ketorolac decreases the subjective perception of pain after laparoscopic urologic surgery. It is suggested that ketorolac administration decreases the amount of narcotic usage as well. Time to resumption of oral intake and length of hospital stay were not influenced by use of ketorolac.

Feasibility of telementoring between Baltimore (USA) and Rome (Italy): the first five cases.

BACKGROUND AND PURPOSE: Telemedicine is the use of telecommunication technology to deliver healthcare. Telementoring has been developed to allow a surgeon at a remote site to offer guidance and assistance to a less-experienced surgeon. We report on our experience during laparoscopic urologic procedures with mentoring between Rome, Italy, and Baltimore, USA. MATERIAL AND METHODS: Over a period of 3 months, two laparoscopic left spermatic vein ligations, one retroperitoneal renal biopsy, one laparoscopic nephrectomy, and one percutaneous access to the kidney were telementored. Transperitoneal laparoscopic cases were performed with the use of AESOP, a robotic for remote manipulation of the endoscopic camera. A second robot, PAKY, was used to perform radiologically guided needle orientation and insertion for percutaneous renal access. In addition to controlling the robotic devices, the system provided real-time video display for either the laparoscope or an externally mounted camera located in the operating room, full duplex audio, telestration over live video, and access to electrocautery for tissue cutting or hemostasis. RESULTS: All procedures were accomplished with an uneventful postoperative course. One technical failure occurred because the robotic device was not properly positioned on the operating table. The round-trip delay of image transmission was less than 1 second. CONCLUSION: International telementoring is a feasible technique that can enhance surgeon education and decrease the likelihood of complications attributable to inexperience with new operative techniques.

Retroperitoneal access for transperitoneal laparoscopy in patients at high risk for intra-abdominal scarring.

BACKGROUND AND PURPOSE: Adhesions from prior extensive open abdominal surgery can make initial transperitoneal access for laparoscopy hazardous. An alternative to open port placement is a retroperitoneal approach to the peritoneal cavity. We describe our retroperitoneal access for transperitoneal laparoscopy and evaluate the success of the subsequent laparoscopic procedure. PATIENTS AND METHODS: Eight patients with a history of abdominal surgery have undergone retroperitoneal access to the peritoneum prior to a laparoscopic urologic procedure. With the patient in a lateral decubitus position, the retroperitoneum is entered with a 10-mm Visiport device (US Surgical Corp., Norwalk, CT) along the posterior axillary line. A working space is bluntly created, the peritoneum identified anterior to the colon, and the endoscope passed through a peritoneotomy. The abdomen is then inspected, transperitoneal ports are strategically placed under direct vision, and the intended procedure is commenced. RESULTS: In all cases, retroperitoneal access to the peritoneum and subsequent trocar placement was successful. In five cases, the intended procedure was completed laparoscopically. In a case of bilateral ureterolysis, one side was completed laparoscopically; however, the other required open conversion. In two nephrectomies for xanthogranulomatous pyelonephritis (XGP), open conversion was necessary because of fibrosis. CONCLUSION: Retroperitoneal access to the peritoneal cavity permits safe and effective port placement when previous abdominal surgery makes initial transabdominal access difficult. However, despite successful access, in patients at risk for extensive perinephric fibrosis (e.g., XGP), a high incidence of open conversion may be expected.

The EndoHand: comparison with standard laparoscopic instrumentation.

Laparoscopic instrumentation is constantly being refined in an attempt to achieve the proficiency, flexibility, and tactile feedback that would be available if the human hand were small enough to be used in laparoscopic surgery. The EndoHand (DAUM GmbH, Schwerin, Germany) is a novel laparoscopic three-fingered hand developed as an advancement over standard laparoscopic tools. Grasping and manipulation ability, dexterity, and tactile feedback were compared with those of current laparoscopic instrumentation. Experiments included measurement of achievable angles of approach to a fixed point behind a 2-cm-tall obstruction, completion time and error rates during a pelvic trainer dexterity task, and tactile feedback using a device invented to simulate tissue resistance. Subjectively, the EndoHand was able to pick up a range of objects similar to those graspable by a Babcock clamp. More complex types of manipulation were possible with the EndoHand because of its wrist joint. The range of approach angles to the fixed point was 35 degrees to 90 degrees with the EndoHand and 70 degrees to 90 degrees with the straight instruments. The dexterity of the EndoHand was significantly less than that of the other two instruments, as measured by time (P = 0.0002) and errors (P = 0.02). Standard instruments were also more accurate in the tactile feedback trials (P = 0.02). The EndoHand is a prototype of a unique new generation of laparoscopic instruments. Although it falls short in both dexterity and tactile feedback, significant promise is shown in its ability to perform sophisticated manipulation of objects and its flexibility to work at a larger range of angles to the target tissue. The EndoHand may be most useful on the nondominant hand of the surgeon to assist with positioning and holding tissue in a specific orientation. Clinical trials will determine its eventual role in laparoscopic surgery.

Fibrous coagulum: a new cause of retained fragments following extracorporeal shock wave lithotripsy.

PURPOSE: A previously unrecognized cause of retained fragments following extracorporeal shock wave therapy is identified. MATERIALS AND METHODS: Nine patients referred for percutaneous stone extraction following failure of multiple shock wave lithotripsy treatments had retained fragments embedded in soft tissue. The stones were evaluated by chemical analysis and the tissue was evaluated histologically. RESULTS: All stones contained calcium and histopathology confirmed the presence of fibrous tissue. Radiographs were unable to predict the presence of the substance preoperatively. CONCLUSIONS: We identified fibrous coagulum as a cause of retained fragments following shock wave lithotripsy. The material is soft tissue and cannot be ablated by further shock wave lithotripsy. These findings confirm that repeated shock wave lithotripsy is contraindicated, since stone fragmentation and passage may be inhibited by fibrous coagulum.

Accuracy of computerized tomography in the diagnosis of colovesical fistula secondary to diverticular disease.

We reviewed 9 consecutive patients with colovesical fistula secondary to diverticulitis during a 2-year period. Preoperative evaluation included computerized tomography (CT) and a barium enema or colonoscopy in all patients (8 underwent cystoscopy). All patients subsequently underwent laparotomy with a single or multiple staged repair. Using CT criteria for diagnosis of colovesical fistulas, the study accurately predicted the presence and location of fistula in 8 patients, and was suspicious in 1. Findings at cystoscopy only diagnosed 3 fistulas and were suspicious in 4. The remaining diagnostic tests, including excretory urography, barium enema, abdominal plain films, colonoscopy and cystogram, were unremarkable except for a single cystogram and barium enema. In addition to documenting the fistula, CT provided important intraluminal and extraluminal pathological findings helpful in planning subsequent surgery. Thus, CT should be included in the initial evaluation of patients with suspected colovesical fistula.

Percutaneous endoscopic management of urothelial tumors of the renal pelvis.

Although nephroureterectomy remains the reference standard for the treatment of transitional cell cancer of the renal pelvis, advances in technology and techniques have made percutaneous management of select lesions feasible. We report our technique of staged percutaneous resection of a large renal pelvic transitional cell cancer.

Recurrent bleeding from intercostal arterial pseudoaneurysm after retroperitoneal laparoscopic radical nephrectomy.

We report a case of a 59-year-old man with recurrent bleeding after retroperitoneal laparoscopic nephrectomy. Computed tomography and Doppler ultrasonography confirmed an intercostal artery pseudoaneurysm as the source. Angiography 1 month later demonstrated resolution after conservative management.