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Li-Ming Su

Publications and source records attributed to Li-Ming Su.

34 records · Page 2Linked to original sources
PubMed2004

Defining the complications of cryoablation and radio frequency ablation of small renal tumors: a multi-institutional review.

PURPOSE: Ablative treatments (cryoablation or radio frequency ablation) for renal cell carcinoma aim to decrease morbidity by treating renal tumors in situ, eliminating the need for extirpation. These technologies have potential for complications previously unassociated with renal tumor treatment. We identified complications associated with percutaneous and laparoscopic ablative treatment of renal tumors. MATERIALS AND METHODS: Groups at medical centers with reported experience with ablation of renal tumors were invited to participate in this study. Each group submitted retrospective data regarding overall ablative treatment experience and associated complications. For each incident the nature of the complication, its associated morbidity, the necessity and nature of any subsequent interventions, and the final patient outcome were evaluated. Complications were divided into minor and major categories. Data were collected from groups at 4 institutions with a combined experience of 271 cases. Of these cases 139 were cryoablation and 133 were radio frequency ablation. There were 181 procedures performed percutaneously and 90 performed laparoscopically. RESULTS: A total of 30 complications occurred (11.1%) with 5 major (1.8%) and 25 minor (9.2%) complications, and 1 death (0.4%). Overall 26 of the 30 complications (86.7%) were directly attributable to the ablation procedure. The most common complication was pain or paraesthesia at the probe insertion site. CONCLUSIONS: Ablation technologies appear to have a low complication profile when used to treat small renal tumors. The majority of complications are minor and require observation only. Further study and followup are necessary to determine long-term oncological efficacy.

Adult↗
PubMed2004

Nerve sparing radical prostatectomy: effects of hemostatic energy sources on the recovery of cavernous nerve function in a canine model.

PURPOSE: To preserve sexual function following radical prostatectomy, one must avoid injury to the neurovascular bundles (NVBs). In the conventional open surgical technique, the use of energy sources for hemostasis is avoided to prevent damage to the cavernous nerves. In contrast, during laparoscopic radical prostatectomy, electrosurgical and ultrasonic energy sources are frequently used for hemostasis during dissection of the prostate. In this study, we evaluated the acute and chronic physiological effects of various hemostatic energy sources on cavernous nerve function in the canine model. MATERIALS AND METHODS: A total of 12 dogs were divided into 4 groups based on the type of energy source used for hemostasis during unilateral dissection of the NVB. The groups included conventional dissection with suture ligatures (group 1), monopolar (group 2) or bipolar (group 3) electrosurgery and ultrasonic shears (group 4). The contralateral NVB was left undissected as a control. Erectile function was assessed acutely and after 2 weeks of survival by measuring peak intracavernous pressures in response to cavernous nerve stimulation. RESULTS: Following conventional techniques of nerve sparing, the erectile response to nerve stimulation was unaffected. In contrast, the use of energy sources in proximity to the NVB during nerve preservation was associated with a substantial decrease in erectile response both acutely (74% to 91% decrease compared to controls) and after 2 weeks (93% to 96% decrease). CONCLUSIONS: In the chronic canine model, use of hemostatic energy sources in proximity to the prostate during dissection of the neurovascular bundle is associated with a significantly decreased erectile response to cavernous nerve stimulation.

Animals↗
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

Simultaneous laparoscopic prosthetic mesh inguinal herniorrhaphy during transperitoneal laparoscopic radical prostatectomy.

Concurrent repair of inguinal hernias during open radical retropubic prostatectomy is well described and commonly practiced. With the advent of the laparoscopic approach to radical prostatectomy, the possibility of concurrent laparoscopic hernia repair merits investigation. We present a case of simultaneous prosthetic mesh onlay hernia repair for bilateral inguinal hernias during laparoscopic transperitoneal radical prostatectomy.

Adenocarcinoma↗
PubMed2003

Anterior extraperitoneal approach to laparoscopic retroperitoneal lymph node dissection: a novel technique.

PURPOSE: We describe a novel technique of laparoscopic retroperitoneal lymph node dissection via an anterior extraperitoneal approach. MATERIALS AND METHODS: With the patient in a modified flank position an 8 mm. incision is made along the lateral border of the ipsilateral rectus muscle at the umbilical level. Extraperitoneal space creation with finger dissection is initially made at this site and adequately enlarged with a balloon dilator, followed by gas insufflation and placement of 4 laparoscopic trocars. Laparoscopic retroperitoneal lymph node dissection based on a left modified template is then performed in a completely extraperitoneal manner. RESULTS: Surgical time was 330 minutes, blood loss was 150 ml. and 58 lymph nodes were removed. Resumption of physical activity and oral intake was achieved on postoperative day 1. Hospital stay was 36 hours. Postoperative narcotic requirement was 28 mg. morphine sulfate equivalent. There were no intraoperative or postoperative complications. Normal antegrade ejaculation returned postoperatively. CONCLUSIONS: This novel surgical technique is technically feasible and associated with satisfactory clinical outcomes in our preliminary study. Further studies are necessary to evaluate its potential as an alternative to the previously reported transperitoneal and retroperitoneoscopic approaches to laparoscopic retroperitoneal lymph node dissection.

Adult↗
PubMed2003

Bipolar needle electrocautery for laparoscopic partial nephrectomy without renal vascular occlusion in a porcine model.

OBJECTIVES: To report a novel method of accomplishing laparoscopic lower pole partial nephrectomy in an acute porcine model using a bipolar needle electrode without the need for renal arterial occlusion. METHODS: Six animals (12 renal units) underwent laparoscopic polar nephrectomy using the bipolar needle electrode. After complete laparoscopic mobilization of the lower pole of the kidney, the bipolar needle electrode was repeatedly inserted full-thickness into the renal parenchyma and applied transversely, creating regional ischemia to the entire lower pole without renal vascular occlusion. The specimen was then amputated using laparoscopic scissors. RESULTS: For the 12 laparoscopic partial nephrectomies, the mean operative time was 39 +/- 30 minutes, and the mean blood loss was 90 +/- 112 mL. Of the 12 cases, 10 (83%) were performed successfully with the bipolar needle electrocautery as the only source of hemostasis and without the need for ancillary hemostatic measures. Two of the procedures (17%) required temporary arterial control for hemostasis. For the successful procedures, the mean operative time was 29 +/- 4 minutes, and the mean blood loss was 48 +/- 11 mL. Histologic analysis of the specimens demonstrated coagulative necrosis between 2 and 4 mm from the line of the surgical incision. CONCLUSIONS: Bipolar needle electrocautery is a promising device that can be used to facilitate laparoscopic partial nephrectomy with minimal blood loss and without the need for renal arterial occlusion and warm ischemia. Additional studies are required to optimize the delivery parameters of this device.

Animals↗
PubMed2003

Concomitant surgery with laparoscopic live donor nephrectomy.

Routine live donor evaluations reveal unexpected silent pathologies. Herein, we describe our experience treating such pathologies at the time of laparoscopic donor nephrectomy. We have not encountered any previous reports of such an approach. We prospectively collected data on 321 donors. Concomitant surgeries at the time of procurement included two laparoscopic adrenalectomies, one colposuspension, one laparoscopic cholecystectomy, and one liver biopsy. Mean operative time was 321 min (range 230-380), with a mean blood loss of 280 mL (range 150-500). No blood transfusions were required. The left kidney was procured in four cases. The right kidney was obtained on one occasion. Mean hospital stay was 3 days (median 3, range 2-4). No short- or long-term complications have been identified. Mean follow-up time was 2.63 years (median 2.76, range 2.23-2.99). Four of the five kidney recipients were first-time transplants who had not yet started dialysis. Simultaneous surgical interventions at the time of laparoscopic live kidney donation are safe and can be undertaken in selected cases. This practice is beneficial to both the donor and the recipient, and is likely to become more commonplace with changing practice patterns involving donor evaluation and management.

Adenoma↗
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↗
PubMed2002

Laparoscopic retroperitoneal lymph node dissection after chemotherapy.

OBJECTIVES: To assess the operative feasibility, clinical outcomes, and complications of laparoscopic retroperitoneal lymphadenectomy (RPLND) after chemotherapy. METHODS: A retrospective review of clinical records from 7 patients who underwent laparoscopic RPLND after chemotherapy was performed. Five patients presented with nonseminomatous germ cell tumor after orchiectomy. One patient was diagnosed with pure seminoma and one with epididymal small cell cancer. All 7 patients received multiagent chemotherapy for clinical Stage IIA or higher disease, followed by laparoscopic RPLND for findings of a residual retroperitoneal mass on computed tomography or a prechemotherapy mass size greater than 3.0 cm. The mean tumor diameter was 3.07 cm before chemotherapy and 1.91 cm after chemotherapy. A modified laparoscopic left (n = 3), right (n = 3), and bilateral (n = 1) template was used. None of the patients had received radiotherapy before surgery. RESULTS: Postchemotherapy laparoscopic RPLND was successfully completed in 5 (71.4%) of 7 patients. Two patients required a conversion to open surgery. The overall complication rate was 57.1% (4 of 7), with a major complication incidence of 42.8% (3 of 7). No mortalities were recorded. Of the 5 patients who presented with nonseminomatous germ cell tumor after orchiectomy, 3 were found to have retroperitoneal lymph nodes consistent with mature teratoma, 1 had necrotic tissue, and 1 had residual viable tumor. CONCLUSIONS: Laparoscopic RPLND is a feasible operation in patients after systemic chemotherapy. This technique remains challenging at this time and should be reserved for patients with limited residual disease and should only be performed at institutions with considerable laparoscopic expertise.

Adult↗
PubMed2002

Laparoscopic donor nephrectomy in the elderly patient.

OBJECTIVES: To evaluate retrospectively the outcome of laparoscopic donor nephrectomy in patients aged 65 years or older, because data regarding tolerance profile and renal allograft outcome of laparoscopic donor nephrectomy in the elderly patient are lacking. METHODS: Since February 1995, 6 patients aged 65 years or older underwent laparoscopic donor nephrectomy for living-related renal transplantation. Patient demographic, intraoperative, and postoperative parameters, as well as renal allograft outcome, were evaluated. RESULTS: The median donor age was 69.5 years (range 65 to 74), and the median American Society of Anesthesiologists score was 2 (range 2 to 3). The median operative time was 240 minutes (range 183 to 298), with a median blood loss of 300 mL (range 150 to 400). No intraoperative complications or open conversions occurred. Postoperatively, the median time to resumption of oral intake was 1 day (range 1 to 3), and the median hospital stay was 3 days (range 2 to 4). The median narcotic analgesic requirement was 17 mg (range 11 to 27) morphine sulfate equivalent, and the median convalescence was 2 weeks (range 1 to 4). The 1-year renal allograft survival was 100% (n = 6). CONCLUSIONS: Laparoscopic donor nephrectomy is well tolerated by the elderly patient and provides satisfactory patient and renal allograft outcome. Although our sample size was small, it appears that laparoscopy is an acceptable modality for renal donation in the elderly population.

Adult↗
PubMed2002

Renovascular complications of laparoscopic donor nephrectomy.

OBJECTIVES: To review the operative renovascular injuries related to our laparoscopic donor nephrectomy experience, since management of intraoperative renovascular complications during laparoscopic nephrectomy can present a serious challenge. METHODS: During a 6-year period, 353 patients underwent laparoscopic donor nephrectomy. A retrospective chart review was performed to identify and evaluate the renovascular complications associated with the procedure. RESULTS: Eight cases (2.3%) of renovascular complications were identified. Vascular injury involved the renal artery in 6 cases and the renal vein in 2 cases. The etiologies included endovascular GIA stapling failure (n = 2), surgical clip dislodgment (n = 2), and vessel laceration during dissection or stapling (n = 4). Open conversion was necessary in 6 cases (75%). No patient mortality or allograft loss occurred. CONCLUSIONS: Laparoscopic donor nephrectomy is associated with a low incidence of renovascular complications. Laparoscopic or open surgical management may be required when problems arise to optimize donor safety and allograft survival.

Female↗
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↗
PubMed2002

Comparison of intussusception pull-through end-to-side and conventional end-to-side microsurgical vasoepididymostomy: prospective randomized controlled study in male wistar rats.

PURPOSE: Vasoepididymostomy is a technically challenging and complex microsurgical procedure. Recently a new triangulation end-to-side microsurgical technique was reported that allows intussusception of the epididymal tubule into the vasal lumen, resulting in a higher clinical patency rate of 92% with shorter operative time in preliminary clinical studies. We performed a prospective controlled randomized study comparing the patency rate, postoperative sperm granuloma rate and operating time of conventional and intussusception end-to-side vasoepididymostomy in previously vasectomized rats. MATERIALS AND METHODS: We randomized 42, 6-week-old male Wistar rats into 4 groups, including 6 into the sham operation, and 12 each into the control, conventional end-to-side and intussusception end-to-side vasoepididymostomy groups. Bilateral 2-clip vasectomy was performed in all animals except those in the sham operation group. Bilateral intussusception or conventional end-to-side vasoepididymostomy was performed in the assigned animals 2 weeks after vasectomy. Animals in the control group underwent vasectomy only. In the sham operation group the testes were mobilized out of the scrotum and then returned. Rats were sacrificed at 8, 12, 16 and 24 weeks, respectively. The anastomosis and vasectomy sites were inspected for sperm granuloma. To assess patency the abdominal end of the vas was transected and intraluminal fluid was examined microscopically at 400x magnification for the presence of motile sperm. Patency was further confirmed by performing retrograde indigo carmine vasography through the anastomoses. RESULTS: In the intussusception and conventional groups the patency rate was 91.7% and 54.2% (p = 0.004), the sperm granuloma rate was 20.8% and 58.4% (p = 0.035), and average operative time was 65.8 and 67.7 minutes (p = 0.197), respectively. CONCLUSIONS: Intussusception end-to-side vasoepididymostomy is superior to conventional end-to-side vasoepididymostomy with respect to the patency and postoperative sperm granuloma rates. Further investigations are required to confirm such findings clinically in humans.

Anastomosis, Surgical↗
PubMedDate not supplied

Treatment of renal tumors with radiofrequency ablation.

BACKGROUND: Radiofrequency (RF) energy has been investigated as a minimally invasive modality for ablating small renal tumors. Recent advances in the application of this technology have improved its safety and effectiveness. MATERIALS AND METHODS: We describe the technology of RF application and review the current delivery systems as applied to renal tumor ablation. We also review relevant animal studies, which have revealed the natural history of ablated renal tissue. Finally, we examine recent human trials with an emphasis on longer-term follow-up, imaging, complications, and successful ablation according to tumor location within the kidney; i.e., central v peripheral. RESULTS: Radiofrequency ablation can be performed safely in a minimally invasive fashion either percutaneously or laparoscopically. Energy delivery varies, and available systems include dry, wet, cooled-tip, and bipolar electrodes. Heat rise and subsequent charring in the tissue adjacent to the electrode is limited by temperature or impedance-based feedback systems. In animal studies, ablation results in complete cell kill, as judged by nicotinamide adenine dinucleotide diaphorase staining. Clinical trials with intermediate follow-up show excellent success rates. Tumors >3 cm and central tumors have a higher recurrence rate after RFA than smaller, more peripheral tumors. CONCLUSIONS: The current literature suggests that RFA is a promising minimally invasive method of treating small renal tumors. Nevertheless, long-term follow-up is still required, and questions remain regarding the optimal delivery system, duration of ablation, and method of surveillance.

Animals↗