Search PubMed⌕ Search

Biomedical subjects

Thomas W Jarrett

Publications and source records attributed to Thomas W Jarrett.

At least 55 records · Page 3Linked to original sources
PubMed2004

Laparoscopic partial nephrectomy: effect of warm ischemia on serum creatinine.

PURPOSE: Laparoscopic partial nephrectomy (LPN) has been shown to be a safe and effective option for small renal tumors. However, limited data are available regarding the effect of warm ischemic time on postoperative renal function. We assessed the effect of variable durations of warm ischemia on long-term renal function in patients undergoing LPN. MATERIALS AND METHODS: A total of 118 patients with a single, unilateral, sporadic renal tumor and normal contralateral kidney underwent LPN from August 1998 to November 2002. Patients were divided into 3 groups based on warm ischemic time, namely group 1-no renal occlusion in 42, group 2-warm ischemia less than 30 minutes in 48 and group 3-warm ischemia greater than 30 minutes in 28. All 3 groups were assessed for changes in serum creatinine 6 months after LPN. Additionally, renal remnants were examined with cross-sectional imaging. RESULTS: At a median followup of 28 months (range 6 to 56) median creatinine had not statistically increased postoperatively. None of the 118 patients progressed to renal insufficiency or required dialysis after LPN. CONCLUSIONS: Based on postoperative serum creatinine warm ischemia time up to 55 minutes does not significantly influence long-term renal function after LPN. Thus, during LPN efforts to minimize warm ischemia are important but they should not jeopardize cancer control, hemostasis or collecting system closure.

Adult↗
PubMed2004

Laparoscopic live donor nephrectomy: trends in donor and recipient morbidity following 381 consecutive cases.

OBJECTIVE: To review a single-institution 6-year experience with laparoscopic live donor nephrectomy detailing the technical modifications, clinical results, as well as the trends in donor and recipient morbidity. SUMMARY BACKGROUND DATA: Since 1995, laparoscopic donor nephrectomy has had a significant impact on the field of renal transplantation, resulting in decreased donor morbidity, without jeopardizing procurement of a high-quality renal allograft. This technique has become the preferred method of allograft procurement for many transplantation centers worldwide but still remains technically challenging with a steep learning curve. METHODS: Records from 381 consecutive laparoscopic donor nephrectomies were reviewed with evaluation of both donor and recipient outcomes. Trends in donor and recipient complications were assessed over time by comparing the outcomes between four equally divided groups. RESULTS: All 381 kidneys were procured and transplanted successfully with only 8 (2.1%) open conversions. Mean operative time was 252.9 +/- 55.7 minutes, estimated blood loss 344.2 +/- 690.3 mL, warm ischemia time 4.9 +/- 3.4 minutes, and donor length of stay was 3.3 +/- 4.5 days. There was a significant decline in total donor complications, allograft loss, and rate of vascular thrombosis with experience. The rate of ureteral complications declined significantly when comparing our early (Group A) versus later (Groups B-D) experience. CONCLUSION: Laparoscopic donor nephrectomy has remained a safe, less invasive, and effective technique for renal allograft procurement. Over our 6-year experience and with specific refinements in surgical technique, we have observed a decline in both donor and recipient morbidity following laparoscopic live donor nephrectomy.

Cohort Studies↗
PubMed2003

Pleural injury during laparoscopic renal surgery: early recognition and management.

PURPOSE: Injury to the diaphragm is an uncommon yet recognized complication of several laparoscopic procedures, including laparoscopic renal surgery. As these procedures increase in popularity and use, laparoscopic surgeons should be aware of techniques for avoiding this complication as well as methods of identifying pleural injury and managing it appropriately. We report our experience with the detection and intraoperative management of pleural injury sustained during laparoscopic renal surgery and its subsequent treatment. MATERIALS AND METHODS: From July 1993 to April 2001 at 4 institutions 1,765 patients underwent laparoscopic renal surgery for benign and malignant disease as well as for live renal donation. We retrospectively reviewed the charts and interviewed the primary surgeons to determine the etiology of pleural injury, intraoperative detection and management, and possible future prevention. RESULTS: Pleural injury occurred in 10 cases (0.6%). In 2 cases injury involved inadvertent trocar placement through the pleural cavity. These cases were managed by intraoperative chest tube placement. In 8 cases the diaphragm was injured in iatrogenic fashion during kidney dissection, including during splenic mobilization in 2, liver mobilization in 2, ascending colon mobilization in 1, dissection of the upper renal pole in 2 and dissection of a large renal cyst off of the diaphragm in 1. In all patients injury was detected intraoperatively and repaired via laparoscopy. In 1 patient residual pneumothorax postoperatively necessitated tube thoracostomy. CONCLUSIONS: Pleural injury sustained during laparoscopic surgery is an uncommon but potentially serious complication of laparoscopic renal procedures. The experienced laparoscopic surgeon can identify and repair the injury intraoperatively, minimizing patient morbidity postoperatively.

Diaphragm↗
PubMed2003

Percutaneous computed tomography-guided radiofrequency ablation of renal masses in high surgical risk patients: preliminary results.

This article evaluates the safety and efficacy of percutaneous radiofrequency ablation (RFA) delivered by computed tomography (CT) fluoroscopic guidance for the treatment of small, solitary renal lesions in high risk surgical and anesthetic patients. In total, 29 patients with 35 small (</=4 cm) renal lesions underwent a total of 37 CT fluoroscopically guided RFA treatments using a dry RFA technique. Because of medical comorbidities, 26 patients were considered high surgical risk candidates, and 3 patients had von Hippel-Lindau disease. Procedures were performed percutaneously, under intravenous sedation and on an outpatient basis. Renal lesions were monitored on a 3-month basis using precontrast- and postcontrast-enhanced CT imaging to assess for the presence of growth or residual lesion enhancement. Of 37 RFA treatments, 35 (95%) were successfully performed under intravenous sedation and 32 (86%) treatments were performed on an outpatient basis. Over a mean radiographic follow-up period of 9 months, 33 of 35 (94%) renal lesions have required only a single RFA treatment, and 2 patients required a second, successful retreatment for small regions of residual enhancement on follow-up CT imaging. Of 13 renal lesions with a >/=12-month radiographic follow-up interval, 11 (85%) have demonstrated no residual enhancement or growth after RFA. Percutaneous RFA of small, solitary renal lesions is well tolerated in high surgical risk patients. Although early results are encouraging, longer-term follow-up time is necessary to determine the precise role of RFA in this patient population. high resolution video, medium resolution video, low resolution video

Aged↗
PubMed2003

Is telesurgery a new reality? Our experience with laparoscopic and percutaneous procedures.

BACKGROUND: Minimally invasive surgery offers many advantages, but its correct practice is associated with a steep learning curve. Telesurgery allows a surgeon at a remote site to guide and teach surgeons at a primary site by utilizing robotic devices, telecommunications, and video technology, thereby reducing complications. PATIENTS AND METHODS: From September 1998 to July 2000, 17 procedures were telementored between two sites 9230 km apart: a primary operating room at the Policlinico Casilino "Tor Vergata" University of Rome and a remote site at the Johns Hopkins Medical Institutions in Baltimore. Of these procedures, 14 were laparoscopic cases: 8 spermatic vein ligations, 2 retroperitoneal renal biopsies, 3 simple nephrectomies, and 1 pyeloplasty. Three procedures were carried out to obtain percutaneous renal access. All procedures were performed with the help of two robots: the first robot, AESOP, for the orientation of the laparoscope, and the second one, PAKY, to perform the percutaneous renal access. In addition to the robotic device, the system provided four ISDN lines, a PC with dedicated software to manage the connection, audio and video connections, an external video camera with a panoramic view of the operating room, and remote control of the electrocautery and the Telestrator. RESULTS: All the procedures were accomplished with an uneventful postoperative course. Ten operative cases were telementored successfully. In five cases, it was not possible to establish a connection to the remote site, and two procedures were converted to open surgery because of intraoperative complications. The time delay of the image transmission was <1 second. CONCLUSION: This preliminary experience has demonstrated the feasibility of international telementoring. It could provide education to surgeons and decrease the likelihood of complications attributable to inexperience with new techniques.

Humans↗
PubMed2003

Demographics of 353 laparoscopic renal donor and recipient pairs at the Johns Hopkins Medical Institutions.

BACKGROUND AND PURPOSE: The demographics of laparoscopic donor nephrectomy (LDN) have not been characterized in detail. The aim of this study was to review our LDN experience with respect to donor and recipient demographic characteristics and trends. PATIENTS AND METHODS: Over a 6-year period, 353 patients underwent LDN. A retrospective chart review was performed to identify the donor and recipient demographic characteristics and trends associated with the procedure. RESULTS: Among the donors, the mean age was 41 years, with a predominance of females (59.2%), whites (76.2%), and blood relations (72%). Siblings were the most common related-donor-to-recipient relationship, and spouses were the most common unrelated relationships. Among the recipients, the mean age was 43 years, with a predominance of males (58.4%), whites (73.7%), and dialysis-dependent patients (55%). Diabetes mellitus and hypertension were the most common causes of end-stage renal failure. With the introduction of laparoscopy, there was a nearly twofold increase in the total number of live renal donations, and there was a significant expansion in the unrelated-donor pool. CONCLUSIONS: Laparoscopic harvest of donated kidneys is associated with new trends that may help alleviate the current organ shortage.

Adolescent↗
PubMed2003

Ipsilateral orchialgia after laparoscopic donor nephrectomy.

BACKGROUND AND PURPOSE: Complications related to laparoscopic donor nephrectomy (LDN) have been similar to those associated with open renal donor nephrectomy (ODN). However, during clinical follow-up, we noted a group of male patients who developed acute ipsilateral orchialgia after LDN. In an effort to assess the incidence of this problem, determine the etiology, and adapt preventive measures, we reviewed our experience. PATIENTS AND METHODS: A retrospective chart review was performed on 381 consecutive LDNs performed between February 1995 and November 2001 to assess for postoperative orchialgia. There were 157 male patients (41.2%) in our series. Our technique involves ligation of the gonadal vessels, periureteral tissue, and ureter over the iliac artery using either surgical clips or a linear laparoscopic GIA stapler. RESULTS: Left-sided nephrectomy was performed in 145 (92.3%) male patients, of whom 14 (9.6%) complained of ipsilateral orchialgia. Statistical analysis (t-test) of the orchialgia and non-orchialgia groups with respect to operative time, estimated blood loss, warm ischemia time, and ureteral length revealed no statistical differences (P>0.1). Onset of testicular pain occurred on average at postoperative day 5 (range days 1-14). The mean follow-up was 24.4 +/- 14.8 months (range 6-52 months). Ten patients were evaluated with transcrotal duplex ultrasonography. One patient with decreased flow and was managed conservatively, while one patient without detectable testicular flow underwent surgical exploration. One patient underwent spermatocelectomy and had improvement but not resolution of pain. The remaining patients were treated conservatively with nonsteroidal anti-inflammatory medication and empiric antibiotics. Seven patients (50%) had complete spontaneous resolution of orchialgia on average 6.3+/-7.2 months after LDN. CONCLUSION: Laparoscopic donor nephrectomy has proven to be an effective and safe surgical procedure. However, further evaluation has demonstrated a complication not previously reported, namely ipsilateral orchialgia. The etiology remains unclear but may be injury to the sensory nerves of the testicle during dissection of the periureteral tissue or transection of the spermatic cord. Further anatomic and physiological studies are needed to elucidate the pathophysiology of this problem.

Adult↗
PubMed2003

Urinary stone size: comparison of abdominal plain radiography and noncontrast CT measurements.

BACKGROUND AND PURPOSE: To compare urinary stone size as measured by abdominal plain radiography (AXR) with stone size as measured by noncontrast three-dimensional spiral CT in patients with acute renal colic. PATIENTS AND METHODS: Patients presenting to the emergency room of a single institution with urinary stones that were visible on both AXR and noncontrast spiral CT were identified. Two radiologists blinded to the clinical outcomes separately and randomly reviewed all films and measured maximum longitudinal (craniocaudal) and transverse (anteroposterior) stone diameters. The two-tailed paired Student's t-test was used to compare the sizes of each stone on AXR and CT. RESULTS: Over a 1-year period, 22 patients were identified with a total of 31 urinary stones visible on both AXR and CT. Nineteen stones were located in the kidney, three in the midureter, and nine in the distal ureter. The mean stone size by AXR was 6.1 mm (range 2-13 mm; SD +/- 1.95) in the longitudinal axis and 5.3 mm (range 2-11 mm; SD +/- 1.50) in the transverse axis. The mean stone size by CT was 6.9 mm (range 3-12 mm; SD +/- 1.95) in the longitudinal axis and 6.1 mm (range 2-11 mm; SD +/- 1.50) in the transverse. The differences between AXR and CT measurements did not attain significance in either the longitudinal (p = 0.67) or the transverse (p = 0.25) axis. CONCLUSIONS: A CT scan provides estimates of stone size that are consistently greater than those of AXR in both the longitudinal and transverse axes. However, for stones between 2 and 13 mm in maximum diameter, these differences do not attain significance. In patients with a history of radiopaque stones in this size range, therefore, AXR may provide useful size data for clinical decision-making without concern about significant disparities between the two modalities. As AXRs are more expeditiously obtained, incur less direct costs, and expose patients to significantly lower doses of radiation than CT scans, they remain a useful adjunctive study in the work-up of nephrolithiasis.

Adult↗
PubMed2003

Management of obliterated urinary segments using a laser fiber for access.

PURPOSE: We describe a modification of the cut to the light and core-through procedures using a laser fiber to gain through and through access for treatment of complete occlusion of the ureter or urethra. MATERIALS AND METHODS: Three patients presented with complete obliteration of the ureter (2) and vesicourethral anastomosis (1). In each case the laser fiber was advanced through the obliterated segment under direct vision and then exchanged for a standard guide wire using an open ended catheter. RESULTS: Through and through access was obtained in all 3 cases and allowed subsequent incision for repair. In all 3 patients the area of incision was stented and urinary continuity was restored. CONCLUSIONS: Loss of access can lead to complications and termination of any endoscopic procedure. Use of the laser fiber to incise through the obliterated segment and subsequently act as a guide wire in our experience minimized the possibility for loss of access. The disadvantage is the cost of the laser fiber, which cannot be reused. Use of a laser fiber as a guide wire can be a viable and effective option for gaining access across strictures when alternative methods fail.

Aged↗
PubMed2003

Optical access trocar injuries in urological laparoscopic surgery.

PURPOSE: Inadvertent injuries during trocar and Veress needle placement are a rare but potentially serious complication of laparoscopic surgery. An access alternative is an optical trocar under direct vision. Limited data are available regarding the safety of this technique. We reviewed complications related to optical access trocars during standard transperitoneal urological laparoscopic procedures performed at a single institution. MATERIALS AND METHODS: From 1995 to 2001 the optical access trocar was used as the initial trocar in 1,283 urological laparoscopic procedures. The procedures included simple and radical nephrectomy in 309 cases, donor nephrectomy in 386, partial nephrectomy in 79, pyeloplasty in 173 and various other procedures in 336. Intra-abdominal complications caused by optical access trocar were assessed. RESULTS: The optical trocar was inserted at the umbilicus in 88 patients (7.4%), in the right upper quadrant in 445 (34.7%) and in the left upper quadrant in 750 (58.5%). There were 4 injuries (0.31%) associated with the optical access trocar. Complications occurred on the left side in 3 cases and on the right side in 1, including 1 injury to bowel, 1 mesenteric injury resulting in a retroperitoneal hematoma and 2 injuries to epigastric vessels. Three cases were recognized and repaired immediately but in a case of epigastric vessel injury the expanding abdominal wall hematoma required postoperative repair. CONCLUSIONS: Optical access trocars provide a safe and rapid technique for initial trocar placement. Results of this large series support the finding that few trocar related complications are associated with the optical access trocar.

Adolescent↗
PubMed2003

Laparoscopic radical versus partial nephrectomy: assessment of complications.

PURPOSE: We evaluated the short-term morbidity and complications of laparoscopic radical nephrectomy (LRN) compared with laparoscopic partial nephrectomy (LPN). MATERIALS AND METHODS: From May 1998 to May 2002, 114 patients were identified with a single unilateral sporadic renal tumor and a normal contralateral kidney. These individuals had undergone LRN (35) or LPN (79). RESULTS: The LRN and LPN groups were analyzed for age, sex, American Society of Anesthesiologists score and body mass index. Mean tumor size in patients undergoing LRN and LPN was 2.8 +/- 1.2 (range 0.9 to 4.5) and 2.5 +/- 1.0 cm (range 1 to 4.5), respectively (p = 0.17). There were no differences between the 2 groups in terms of mean hospital stay, blood transfusion or surgical complications. There was no difference in mean preoperative and postoperative serum creatinine in patients in the LPN group. Mean postoperative serum creatinine was significantly higher than the mean preoperative level in patients in the LRN group (1.51 +/- 0.22 vs 1.18 +/- 0.37 mg/ml, range 0.6 to 2.4, p = 0.02). In each group 1 case was converted to open surgery due to bleeding. CONCLUSIONS: LPN is associated with similar postoperative convalescence and complications compared with LRN. The increase in serum creatinine noted in patients undergoing radical extirpation supports the use of LPN when clinically indicated.

Adult↗
PubMed2003

Laparoscopic nephrectomy: assessment of morcellation versus intact specimen extraction on postoperative status.

PURPOSE: We compared pathological evaluation and postoperative recovery in patients undergoing transperitoneal laparoscopic nephrectomy at our institution with morcellated vs intact specimen extraction. MATERIALS AND METHODS: A prospective evaluation of 57 consecutive patients undergoing radical and simple transperitoneal laparoscopic nephrectomy was reviewed. One patient was excluded from study due to transitional cell carcinoma, which was detected intraoperatively. The 33 morcellated specimens were extracted at the umbilical port and the 23 intact specimens were extracted through a midline infraumbilical incision. Data were obtained on narcotic requirements, hospital stay, complications, estimated blood loss, mass size based on preoperative imaging, specimen weight and extraction incision length. RESULTS: Mean incision length in the morcellated and intact specimen removal groups was 1.2 and 7.1 cm, respectively (p <0.001). No significant differences in pain or recovery were noted between the 2 groups. Two cases of microscopic invasion of the perinephric adipose tissue in the intact specimen group were up staged from clinical T1 to pT3a disease. No change in patient treatment was made based on this information. CONCLUSIONS: We did not find a significant difference in surgical time, pain or hospital stay. Only incision length was statistically significant. Postoperative recovery appeared to be similar in these 2 groups. With modern imaging modalities information on pathological stage did not alter patient treatment.

Adolescent↗
PubMed2002

Laparoscopic pyeloplasty: the first 100 cases.

PURPOSE: Laparoscopic pyeloplasty was developed as a minimally invasive alternative to an open procedure for the treatment of ureteropelvic junction obstruction. Long-term followup has not yet been reported. We present experience with the first 100 consecutive cases of laparoscopic pyeloplasty performed at our institution. MATERIALS AND METHODS: A retrospective review of 100 consecutive laparoscopic pyeloplasties in 99 patients (means age 37.3 years) between August 1993 and January 1999 was performed. All patients had radiographic evidence of obstruction with signs, symptoms or deterioration of renal function. Repair was for primary ureteropelvic junction obstruction in 83 patients and secondary obstruction in 17. The 4 types of repairs performed were Anderson-Hynes dismembered (71 cases), Y-V plasty (20), Heineke-Mirhulicz (8) and Davis intubated ureterotomy (1). Type of repair used was dictated by intraoperative findings. Twenty patients had nonobstructing renal stones and underwent concomitant pyelolithotomy. All patients were assessed for symptoms and radiographic evaluation for anatomical obstruction. RESULTS: Average operating room time was 4.2 hours, which decreased with surgeon experience. Average blood loss was 181 cc and hospital stay was 3.3 days. Two patients required blood transfusion. A crossing vessel was found in 57 patients. With a mean clinical and radiographic followup of 2.7 and 2.2 years, respectively, 96% of the patients were free of obstruction on followup radiographic imaging. Of the patients who underwent concomitant pyelolithotomy, 18 (90%) were stone-free at last followup. All failures occurred within the first postoperative year. There were 12 complications in this series. CONCLUSIONS: In experienced hands laparoscopic pyeloplasty is an effective alternative treatment for symptomatic ureteropelvic junction obstruction. The results appear durable and comparable to open pyeloplasty with decreased postoperative morbidity.

Adolescent↗
PubMed2002

Early repeated exploration after laparoscopic urologic surgery: comparison of clinical, radiologic, and surgical findings.

OBJECTIVES: To correlate the clinical scenarios and radiographic findings with the operative findings in patients who underwent repeated exploration to define a management strategy. Postoperative complications after laparoscopy may cause diagnostic challenges because of atypical presentation. METHODS: We retrospectively reviewed the records from 1226 urologic laparoscopic procedures between July 1993 and July 2000. We compared the clinical, radiologic, and surgical findings of patients who underwent repeated exploration within the first month after laparoscopy. RESULTS: During the study period, 9 patients (0.7%) were taken back to the operating room for repeated exploration. The median time for the appearance of symptoms was the second postoperative day. Eight patients were evaluated by computed tomography (CT) and one by both renal Doppler ultrasonography and MAG-3 renal perfusion scan. Repeated operations were laparoscopic in 4 and open in 5 patients. In all the patients evaluated by CT scan, the radiologic findings were consistent with the surgical findings. In the patients who underwent diagnostic laparoscopy because of the severity of clinical findings, despite negative CT findings, no abnormality was discovered at exploration. In 1 patient who was not evaluated by CT, duodenal perforation was detected at exploration. CONCLUSIONS: Clinical findings may not be sufficient for the decision of repeated operation for patients acutely ill after laparoscopy. CT findings correlated well with the findings at exploration. In cases in which no abnormality is detected by CT, it appears reasonable to withhold surgical exploration unless the clinical situation deteriorates.

Adult↗
PubMed2002

Laparoscopic treatment of retroperitoneal fibrosis.

BACKGROUND AND PURPOSE: Retroperitoneal fibrosis (RPF) is an uncommon cause of ureteral obstruction. Surgical treatment is required in most cases. Open ureterolysis, although effective, is associated with significant morbidity and mortality rates. We present data on a series of 13 patients undergoing laparoscopic ureterolysis for RPF. PATIENTS AND METHODS: Between December 1994 and October 2000, 13 patients with RPF underwent laparoscopic ureterolysis at our institution. Operative time, complications, estimated intraoperative blood loss, time to oral intake, amount of parenteral analgesics used, and length of hospital stay were reviewed. Postoperative pyelography or diuretic urography was performed to assess ureteral patency. RESULTS: Laparoscopic ureterolysis was successful in 11 patients (85%); two conversions to open surgery were needed (15%). One patient required a laparoscopic Boari flap on one side because of intense fibrosis. Four postoperative complications (30%) were managed with conservative measures. At a mean follow-up of 30 months, intravenous urography or renal scan showed relief of obstruction in 92% of the patients. CONCLUSIONS: Laparoscopic ureterolysis is an option to treat RPF. It is not free of complications and failures, and its precise role in the treatment of RPF still needs to be judged with longer follow-up and larger number of patients.

Adult↗
PubMed2002

High-intensity focused ultrasound ablation of the epididymis in a canine model: a potential alternative to vasectomy.

BACKGROUND AND PURPOSE: High-intensity focused ultrasound (HIFU) is a noninvasive technology capable of inducing thermal coagulative necrosis of subsurface structures without injuring intervening tissues. We have previously reported on the feasibility of HIFU vasectomy in a canine model. In this study, we evaluated the feasibility of HIFU ablation of the canine epididymis as an alternative to vasectomy. The epididymis may be a better target than the vas deferens because it is larger, more easily positioned in the HIFU focal zone, and more susceptible to occlusive injury at lower energy levels, thus reducing collateral damage. MATERIALS AND METHODS: A hand-held HIFU clamp was used to grasp the epididymides of anesthetized dogs (eight surgically exposed and six grasped transcutaneously). An ultrasound transducer in the clamp focused energy on a 1 x 3 x 8-mm target zone centered between the clamp jaws. Ultrasonic energy (6-19 W) was delivered to this target zone for various times (16-150 seconds). The vas, epididymis, and testis were harvested for histologic examination 2 weeks after ablation. RESULTS: Seven of the eight epididymides ablated after surgical exposure demonstrated histologic findings associated with occlusion (fibrosis, hemorrhage, and proximal duct dilatation). Five of the six epididymides ablated transcutaneously also demonstrated histologic evidence of occlusion. Skin burns were evident overlying three epididymides, and one testicular injury was noted adjacent to an ablated region of the epididymis. CONCLUSION: High-intensity focused ultrasound ablation of the epididymis causes injury and histologic changes associated with epididymal occlusion. Further investigations are under way to optimize ablation parameters and to confirm azoospermia with ejaculate studies. Refinement of this technology may provide a rapid noninvasive alternative to conventional vasectomy.

Animals↗
PubMed2002

Robotic percutaneous access to the kidney: comparison with standard manual access.

PURPOSE: To evaluate the efficiency, accuracy, and safety of robotic percutaneous access to the kidney (PAKY) for percutaneous nephrolithotomy in comparison with conventional manual techniques. MATERIALS AND METHODS: We compared the intraoperative access variables (number of access attempts, time to successful access, estimated blood loss, complications) of 23 patients who underwent robotic PAKY with the remote center of motion device (PAKY-RCM) with the same data from a contemporaneous series of 23 patients who underwent conventional manual percutaneous access to the kidney. The PAKY-RCM incorporates a robotic arm and a friction transmission with axial loading system to accurately position and insert a standard 18-gauge needle percutaneously into the kidney. The blood loss during percutaneous access was estimated on a four-point scale (1 = minimal to 4 = large). The color of effluent urine was graded on a four-point scale (1 = clear to 4 = red). RESULTS: The mean target calix width was 13.5 +/- 9.2 mm in the robotic group and 12.2 +/- 4.5 mm in the manual group (P = 0.57). When comparing PAKY-RCM with standard manual techniques, the mean number of attempts was 2.2 +/- 1.6 v 3.2 +/- 2.5 (P = 0.14), time to access was 10.4 +/- 6.5 minutes v 15.1 +/- 8.8 minutes (P = 0.06), estimated blood loss score was 1.3 +/- 0.49 v 1.7 +/- 0.66 (P = 0.14), and color of effluent urine following access was 2.0 +/- 0.90 v 2.1 +/- 0.7 (P = 0.82). The PAKY-RCM was successful in obtaining access in 87% (20 of 23) of cases. The other three patients (13%) required conversion to manual techniques. There were no major intraoperative complications in either group. CONCLUSIONS: Robotic PAKY is a feasible, safe, and efficacious method of obtaining renal access for nephrolithotomy. The number of attempts and time to access were comparable to those of standard manual percutaneous access techniques. These findings provide the groundwork for the development of a completely automated robot-assisted percutaneous renal access device.

Blood Loss, Surgical↗