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Li-Ming Su

Publications and source records attributed to Li-Ming Su.

At least 19 recordsLinked to original sources

Imaging the cavernous nerves in the rat prostate using optical coherence tomography.

INTRODUCTION: Improvements in identification, imaging, and visualization of the cavernous nerves (CNs) during radical prostatectomy, which are responsible for erectile function, may improve nerve preservation and post-operative potency. Optical coherence tomography (OCT) is capable of real-time, high-resolution, cross-sectional, in vivo tissue imaging. The rat prostate serves as an excellent model for studying the use of OCT for imaging the CNs, as the rat CN is a large, visible, and distinct bundle allowing for easy identification with OCT in addition to histologic confirmation. MATERIALS AND METHODS: Imaging was performed with the Niris OCT system and a handheld 8 Fr probe, capable of acquiring real-time images with 11-microm axial and 25-microm lateral resolution in tissue. Open surgical exposure of the prostate was performed on a total of six male rats, and OCT images of the prostate, CN, pelvic plexus ganglion, seminal vesicle, blood vessels, and periprostatic fat were acquired. CN electrical stimulation with simultaneous intracorporeal pressure measurements was performed to confirm proper identification of the CNs. The prostate and CNs were also processed for histologic analysis and further confirmation. RESULTS: Cross-sectional and longitudinal OCT images of the CNs were acquired and compared with histologic sections. The CN and ganglion could be differentiated from the surrounding prostate gland, seminal vesicle, blood vessels, bladder, and fatty tissue. CONCLUSIONS: We report preliminary results of OCT images of the rat CNs with histologic correlation and erectile stimulation measurements, thus providing interpretation of prostate structures as they appear in OCT images.

Animals↗

Complications of 2,775 urological laparoscopic procedures: 1993 to 2005.

PURPOSE: We assessed the complications associated with urological laparoscopic surgery at a single high volume center during a 12-year period. MATERIALS AND METHODS: A retrospective chart analysis was performed, focusing on complications associated with 2,775 laparoscopic surgeries occurring between 1993 and 2005. These included radical nephrectomy (549), partial nephrectomy (345), donor nephrectomy (553), simple nephrectomy (186), pyeloplasty (301), nephroureterectomy (105), retroperitoneal lymph node dissection (86), renal ablation (81), adrenalectomy (106) and radical prostatectomy (463). Complication data were tabulated according to case number, procedure type, patient age, the American Society of Anesthesiologists score, conversion status, length of hospitalization, Clavien classification system and annual complication rate during the study. Statistical analysis was performed with Fisher's exact and chi-square tests. RESULTS: A total of 614 complications (22.1%) occurred within each group, broken down into laparoscopic radical nephrectomy (20%), laparoscopic partial nephrectomy (28%), laparoscopic donor nephrectomy (28%), laparoscopic simple nephrectomy (15%), laparoscopic pyeloplasty (13.3%), laparoscopic nephroureterectomy (40.9%), laparoscopic retroperitoneal lymph node dissection (26.7%), laparoscopic renal tumor ablation (18.6%), laparoscopic adrenalectomy (25.4%) and laparoscopic radical prostatectomy (15%). Total intraoperative and postoperative complication rates were 4.7% and 17.5%, respectively. Vascular injuries were the most common intraoperative complications. Annual complication rates plateaued in the year 2000 and were not significantly different during the ensuing 4 years (p >0.05). Complications correlated with a greater American Society of Anesthesiologists score as well as a longer hospital stay (p <0.05). CONCLUSIONS: The data presented here help define the complication rates for laparoscopic urological procedures in experienced hands at a high volume institution.

Adult↗

Laparoscopic and robotic assisted radical prostatectomy--critical analysis of the results.

OBJECTIVE: To evaluate the role of laparoscopic radical prostatectomy (LRP) and robotic assisted radical prostatectomy (RLRP) based on personal experience and a review of the literature. MATERIAL AND METHODS: Own experience at one European and one American LRP-center includes more than 2000 cases. We performed a MEDLINE search reviewing the literature on LRP and RLRP between 1992 and 2005 with special emphasis on historical aspects, technical considerations, comparison to open retropubic (RRP) and perineal radical prostatectomy (PRP), laparoscopic training, and the cost-efficiency of the techniques. RESULTS: Based on sophisticated training programs a continuous dissemination of the technique took place. In the United States, this process was accelerated by the use of the daVinci-robot. There is a trend towards the extraperitoneal access. Mid-term outcomes of LRP achieved equivalence to open surgery with regards to complications, oncologic and functional results. Distinct advantages of LRP include less postoperative pain, lower rate of complications, shorter convalescence, and better cosmesis. In contrast to RLRP, LRP may reach cost-equivalence with open surgery (i.e. by reduction of OR-time, use of multi-usable instruments). CONCLUSIONS: LRP reproduces the excellent results of open surgery providing the advantages of minimal access. Video-assisted teaching improves the transfer of anatomical knowledge and technical knowhow. In contrast the United States, the use of robots is likely to remain limited in Europe.

Cost-Benefit Analysis↗

Age stratified functional outcomes after laparoscopic radical prostatectomy.

PURPOSE: We assessed health related quality of life in men treated for prostate cancer with laparoscopic radical prostatectomy. MATERIALS AND METHODS: Urinary continence and potency were prospectively assessed in 369 men stratified into age groups, including group 1-younger than 50, group 2-50 to 59 and group 3-60 years or older, by analyzing answers to the Expanded Prostate Cancer Index Composite questionnaire collected preoperatively, and 3, 6 and 12 months after laparoscopic radical prostatectomy. RESULTS: Younger men were more likely to achieve urinary continence (1 pad or less daily) 1 year after laparoscopic radical prostatectomy (groups 1 to 3 100%, 91% and 81%, respectively, p <0.01). Younger men were also more likely to be potent and engaging in intercourse 1 year after bilateral nerve sparing laparoscopic radical prostatectomy (groups 1 to 3 70%, 67% and 46%, respectively, p <0.01). The mean percent return to baseline Expanded Prostate Cancer Index Composite urinary continence subscale at 1 year in groups 1 to 3 was 80%, 79% and 74%, respectively (p = 0.49). The mean percent return to baseline Expanded Prostate Cancer Index Composite sexual function subscale at 1 year in groups 1 to 3 was 68%, 65% and 58%, respectively (p = 0.56). Binary logistic regression modeling using the variables age group, prostate weight, International Prostate Symptom Score and nerve sparing status demonstrated that only younger age group was associated with return to continence at all postoperative time points (p <0.05). Younger age group was associated with return to early potency at 3 and 6 months (p = 0.02 and <0.01, respectively). However, only nerve sparing status was associated with recovery of potency at all time points (p <0.05). CONCLUSIONS: Younger men treated with nerve sparing laparoscopic radical prostatectomy regain urinary control and potency earlier than older men. However, validated questionnaire subscale analyses demonstrated that the return to preoperative baseline urinary continence and sexual function is similar in all age groups by the end of postoperative year 1.

Age Factors↗

Comparison of surgical performance during laparoscopic radical prostatectomy of two robotic camera holders, EndoAssist and AESOP: a pilot study.

OBJECTIVES: Robotic camera holders provide steady camera movement and view during laparoscopic surgery. We compared two such robots, EndoAssist and AESOP, by evaluating timed setup and surgical performance during laparoscopic radical prostatectomy (LRP). METHODS: We prospectively collected data for 20 patients undergoing LRP using either the EndoAssist or AESOP. AESOP was mounted to the surgical bed and controlled by an experienced assistant using a hand-held remote control. The EndoAssist device was placed over the patient's right shoulder. Its movements were executed by the surgeon using a head-mounted optical emitter with brief head movements detected by a sensor mounted atop the surgeon's video monitor. The robot setup time and LRP operative steps were timed and compared between the two cohorts. RESULTS: The time for robot setup favored AESOP over the EndoAssist (2.0 minutes versus 5.3 minutes, P = 0.001). The time for accomplishing vas deferens and seminal vesicle dissection favored the EndoAssist (23 minutes versus 33 minutes, P = 0.04). However, no statistically significant difference was found in the efficiency of task performance between the two robots in any of the other 11 steps measured. CONCLUSIONS: The EndoAssist appears to be equally efficient to the assistant-controlled AESOP robot with respect to surgical performance during LRP. The advantages of the EndoAssist include its accurate response and ability to provide the surgeon with complete control of the desired operative view without relying on an assistant. Its disadvantages include its large profile, lack of a table-mounted design, and the need for pedal activation. Additional modifications are needed to improve the efficiency and design of this novel robotic device further.

Humans↗

Anatomic nerve-sparing laparoscopic radical prostatectomy: comparison of retrograde and antegrade techniques.

OBJECTIVES: To compare the anatomic retrograde and antegrade preservation of the neurovascular bundle (NVB) during laparoscopic radical prostatectomy. METHODS: Anatomic studies were reviewed, focusing on the fascial layers surrounding the prostate and NVB and the terminology used as described by Walsh and colleagues. Important operative steps have been illustrated using video clips. For the retrograde technique, after incision of levator fascia, the NVBs were released from the apex before division of the urethra. Along the plane between the laterally incised Denonvilliers and perirectal fascia, the prostate was mobilized from the rectum. Isolated clipping of the seminal vesicle arteries was performed in an antegrade manner, followed by control of the lateral pedicles, and identification of the course of the NVB. For the antegrade technique, after dissection of the seminal vesicles, the levator fascia was incised to develop a lateral NVB groove. After bladder neck division and lateral pedicle ligation, the lateral NVB groove was used as a guide for antegrade preservation of the NVB. During anastomosis, the NVBs located at the 5-o'clock and 7-o'clock positions were avoided in both techniques. RESULTS: A questionnaire-based potency rate of 67% and 76%, respectively, was reported after bilateral nerve sparing using retrograde and antegrade laparoscopic radical prostatectomy techniques. CONCLUSIONS: Both techniques allowed replication of open surgical principles. The video magnification enabled excellent demonstration of the periprostatic anatomy. The principles of interfascial dissection of the NVB, use of task-specific instrumentation, and avoiding energy sources around the NVB may be more important than the actual nerve-preservation technique used.

Humans↗

Computerized tomography guided percutaneous renal cryoablation with the patient under conscious sedation: initial clinical experience.

PURPOSE: We report on our initial clinical experience with CT guided percutaneous renal cryoablation. MATERIALS AND METHODS: CT guided percutaneous renal cryoablation was performed on 27 tumors using conscious sedation in 20 patients. Eligible patients had tumors of 5 cm or less and were poor surgical candidates or otherwise warranted nephron sparing treatment. Tumors were classified as central or noncentral depending on their relationship to the renal sinus fat. During cryoablation intraoperative active ice ball formation was monitored with real-time CT imaging to ensure adequate tumor coverage. Postoperative followup imaging was obtained at regular intervals. RESULTS: Our method appears technically feasible as of the 27 cryoablations performed, only 1 complication occurred requiring blood transfusion in a patient with a large, centrally located tumor. To date we have 16 tumors in 12 patients with imaging followup of 1 month or more (mean followup 5.9 months). Mean baseline tumor size in this group was 2.5 cm with 11 small (3 cm or less) and 5 large (more than 3 cm) tumors. Of the tumors 5 were centrally located and 11 were noncentrally located. Preliminary data suggest that of the 16 cryoablated tumors 15 showed no signs of enhancement on followup. CONCLUSIONS: CT guided percutaneous renal cryoablation appears to be a feasible treatment option for small, noncentrally located renal tumors. While early results appear promising, longer followup is needed to more clearly define the role of this treatment method.

Adult↗

Laparoscopic techniques for the repair of vaginal vault prolapse: determining if less is more.

Repair of vaginal vault prolapse remains a surgical challenge. Abdominal, vaginal, and combined procedures have been described. The ideal operation remains elusive with regard to outcomes, morbidity, and economics. As an extension of the abdominal approach, laparoscopy continues to gain favor as an access method and as a surgical advancement. Recent studies highlight a number of laparoscopic techniques for restoration of apical support that demonstrate feasibility and encouraging results. Further study is necessary to determine if the minimally invasive nature of laparoscopy can duplicate or surpass standard abdominal and vaginal approaches to the repair of pelvic organ prolapse.

Female↗

Neuromuscular complications after percutaneous radiofrequency ablation of renal tumors.

Neuromuscular complications after percutaneous renal tumor ablation have not been previously reported. In a series of 48 patients undergoing percutaneous ablation, 3 of our patients had neuromuscular complications. One patient developed permanent flank laxity and two had transient paresthesias. Neuromuscular complications are uncommon, but may occur with percutaneous renal ablative surgery.

Aged↗

Health related quality of life before and after laparoscopic radical prostatectomy.

PURPOSE: The viability of laparoscopic radical prostatectomy (LRP) as a surgical treatment for prostate cancer depends on oncological and health related quality of life (HRQOL) outcomes. We present a prospective assessment of HRQOL in 122 patients before and after LRP using the validated Expanded Prostate Cancer Index Composite (EPIC) questionnaire. MATERIALS AND METHODS: EPIC data were collected preoperatively, and at 3, 6 and 12 months after LRP, and all were normalized to patient preoperative baseline responses. RESULTS: Using traditional single question responses, 93.4% of patients were continent (0 to 1 pads) at postoperative month 12. Of previously potent men who underwent bilateral nerve sparing 78.9% reported engaging in sexual intercourse within postoperative year 1. However, EPIC domain scores provided a more comprehensive assessment of functional outcomes. For the urinary incontinence subdomain, the majority of functional recovery was achieved by postoperative month 6, reaching a 74% return to baseline on average. In contrast, recovery of the sexual function subdomain continued throughout postoperative year 1 (to a mean of 64%). Recovery of sexual function was not significantly affected by age or preoperative potency status, although the extent of nerve sparing was a significant predictor of outcome (mean recovery to 75% of baseline for bilateral vs 36% for no nerve sparing at 12 months, p = 0.005). CONCLUSIONS: Nerve sparing LRP provides satisfactory first year HRQOL outcomes when assessed with a validated instrument. The time course and extent of functional recovery documented in this prospective study may prove useful for patient counseling before LRP.

Humans↗

Exploring the learning curve, pathological outcomes and perioperative morbidity of laparoscopic partial nephrectomy performed for renal mass.

PURPOSE: We investigated the learning curve, pathological results and perioperative morbidity of laparoscopic partial nephrectomy (LPN). MATERIALS AND METHODS: The records of all LPN cases at our institution between January 1999 and March 2004 were reviewed. Of 223 cases 217 (97.3%) were performed for an enhancing renal mass. RESULTS: Mean tumor size was 2.6 cm (range 1 to 10) and 95.4% of patients had a normal contralateral kidney. Transient vascular control was performed in 75.1% of cases. Mean operative time (186 minutes) decreased with surgeon experience (p = 0.003) but was independent of tumor size (p = 0.964). Mean warm ischemia time (27.6 minutes) depended on tumor size (p = 0.005) but not on experience (0.964). Mean blood loss was 385 cc and the perioperative transfusion rate was 6.9%. Postoperative complications occurred in 23 cases (10.6%) with the most common being ileus (1.8%), bleeding (1.8%) and urinary leakage (1.4%). Although the mean serum creatinine change after LPN was a function of tumor size (p <0.001), it was clinically insignificant (0.13 mg/dl). No significant relationship was observed between warm ischemia time and creatinine change (p = 0.262). The final pathological evaluation revealed renal cell carcinoma in 144 patients (66.4%) and the overall positive margin rate was 3.5%. Only 2 renal cell carcinoma recurrences in the operated kidney (1.4%) were identified (mean followup +/- SD 24 +/- 12 months). CONCLUSIONS: LPN is an effective approach for treating small renal masses with low perioperative morbidity. Contrary to previous reports, more than 30% of the enhancing renal lesions excised in this series were found to be benign on final pathological evaluation.

Adult↗

Classification and trends of perioperative morbidities following laparoscopic radical prostatectomy.

PURPOSE: We classified and assessed trends in the incidence, severity and management of perioperative morbidity following laparoscopic radical prostatectomy (LRP). MATERIALS AND METHODS: We retrospectively reviewed the records of 250 patients with clinically localized prostate cancer who underwent transperitoneal LRP, as performed by 2 surgeons (CPP and LMS), between April 2001 and March 2004. The Clavien classification system was used to grade complications for cases completed laparoscopically. RESULTS: In the 246 cases completed laparoscopically 20 grade II, 12 grade III and 2 grade IV complications were noted during a mean followup of 13.7 months (overall complication rate 13.8%). Median hospital stay was 2 days (range 2 to 8) and median duration of bladder catheterization was 10 days (range 3 to 36). Postoperative ileus that prolonged hospital stay was the most frequent complication and it occurred in 8 patients (3.3%). Seven patients required blood transfusion (2.8%). Bladder neck contracture was observed in 3 patients (1.2%). A total of 11 complications occurred in the first 50 cases, while 12, 6, 8 and 1 occurred in cases 51 to 100, 101 to 150, 151 to 200 and 201 to 250, respectively. CONCLUSIONS: Perioperative complications following LRP are mostly self-limited and grade II or III (94.1%). The incidence of complications and need for conversion to open radical prostatectomy decreased with experience. Uniform reporting and grading of surgical complications via a standardized classification system may permit more meaningful comparisons among different centers and surgical techniques.

Adult↗

Percutaneous radio frequency ablation of renal masses: results at a 2-year mean followup.

PURPOSE: We describe our experience with and results of percutaneous computerized tomography guided radio frequency ablation (RFA) for small (less than 4 cm) renal tumors at a 2-year mean followup. MATERIALS AND METHODS: A total of 49 patients (60 renal tumors) with a mean age of 63.9 years underwent percutaneous RFA. Indications for RFA were severe comorbidities or previous abdominal surgery precluding operative management, or hereditary conditions predisposing to multiple tumor recurrence. Persistent enhancement on initial followup imaging was considered incomplete treatment and all such patients underwent biopsy and were offered repeat RFA. Enhancement or enlargement on subsequent imaging was considered tumor recurrence and these patients were counseled regarding further therapy. RESULTS: Three patients (4 tumors) were excluded from evaluation due to death from unrelated causes or loss to followup. A total of 46 patients (56 tumors) were available for evaluation at a mean followup of 27.5 months (range 12 to 48). Six tumors were incompletely treated with the first RFA and successfully treated with a second session. Recurrences after successful initial treatment were seen in 3 of 46 patients. These recurrences developed 24, 25 and 31 months following RFA, respectively, and all occurred in patients with a central tumor of 3.0 cm or greater. Overall local control was achieved in 94.6% of tumors (53 of 56). CONCLUSIONS: RFA is an emerging alternative treatment modality for small renal tumors. Larger (greater than 3.0 cm) central tumors represent unique technical challenges, making these tumors more prone to recurrence. Long-term followup is needed to establish the oncological durability of this technique.

Adult↗

Laparoscopic radical prostatectomy: a multi-institutional study of conversion to open surgery.

OBJECTIVES: To perform a multi-institutional review of the incidence and factors contributing to conversion from laparoscopic radical prostatectomy (LRP) to open radical retropubic prostatectomy (RRP) among eight surgeons. METHODS: The medical records from all patients undergoing LRP at seven institutions were reviewed to assess the incidence of open conversion to RRP. The clinical, operative, pathologic, and functional outcomes of patients who required conversion were compiled and analyzed. RESULTS: Of 670 operations, 13 (1.9%) were converted from LRP to RRP. The most common steps at which conversion occurred were the apical dissection (38%) and the posterior seminal vesicle dissection (31%). Failure to progress was the most common cause of conversion, followed by injury to adjacent structures and hypercarbia. Comorbidities associated with conversion were prior pelvic surgery and obesity (body mass index greater than 30). Six of the 13 conversions occurred in the surgeons' first 5 cases. Despite open conversion, patients were continent (no pads) (92%) and potent (44%) with at least 6 months of follow-up. CONCLUSIONS: Open conversion from LRP to RRP is an uncommon event, but is more likely to occur during a surgeon's early experience. Surgeons beginning their experience with LRP are advised to select their patients carefully to minimize the need for conversion to open surgery. Obese patients and those at risk of periprostatic adhesions should initially not be considered for LRP. Despite open conversion, the functional outcomes did not appear to be adversely affected.

Adenocarcinoma↗

Nerve-sparing laparoscopic radical prostatectomy: replicating the open surgical technique.

OBJECTIVES: To present a detailed demonstration of a nerve-sparing laparoscopic radical prostatectomy (LRP) technique that replicates anatomic nerve-sparing radical retropubic prostatectomy (RRP). Techniques for neurovascular bundle preservation during open RRP have undergone several decades of careful refinement. Identifying pre-existing anatomic planes and the avoidance of thermal injury near the nerves are principles considered paramount during nerve-sparing RRP. During LRP and robotic-assisted radical prostatectomy, the use of cautery for hemostasis during nerve dissection is common despite its unknown effects on cavernous nerve function. METHODS: We describe a combined antegrade and retrograde laparoscopic approach to neurovascular bundle dissection. The technique is demonstrated in the accompanying video segments. The use of specialized laparoscopic instrumentation, including a fine-tipped right-angle clamp and curved dissector, is discussed. The principles of meticulous tissue handling and avoidance of electrocautery are stressed. The preliminary outcomes are presented using data obtained using an abridged version of the International Index of Erectile Function and the Expanded Prostate Cancer Index Composite questionnaires. RESULTS: To date, our technique has been applied to LRP in more than 177 patients. Blood loss has been minimal (less than 300 mL), and intraoperative anatomic nerve preservation appeared excellent. On the basis of our early experience, 76% of patients engaging in sexual intercourse preoperatively who underwent bilateral nerve preservation (n = 21) reported the ability to engage in sexual intercourse 1 year after LRP. CONCLUSIONS: Our nerve-sparing LRP technique replicates established open surgical principles of anatomic nerve-sparing RRP. The techniques described here minimize the potential for cavernous nerve damage from electrical energy or heat. Early functional outcomes appear comparable to the results obtained with open RRP performed at our institution.

Adenocarcinoma↗

Making ends meet: a cost comparison of laparoscopic and open radical retropubic prostatectomy.

PURPOSE: We compared the perioperative costs of laparoscopic radical prostatectomy (LRP) and open radical retropubic prostatectomy (RRP) at a metropolitan hospital by developing a detailed computer model. MATERIALS AND METHODS: Our predictive model incorporates institutional cost centers for operative time, operating room consumables, professional fees, hospital room and board, oral analgesics, autologous blood banking, blood transfusion and cystography. Versions with and without pelvic lymphadenectomy (PLND) were evaluated using 1 and 2-way sensitivity analyses. Operative times, lengths of stay and transfusion rates were derived from published series. We also reviewed individual hospital charges for 172 consecutive prostatectomy cases for comparison and validation of model predictions. RESULTS: The model predicted cost premiums for LRP of 14.4% (without PLND) and 17.5% (with PLND). The actual hospital charge premium for LRP and PLND was 18.4%, which differed from the predicted cost premium by less than 1%. The most significant cost centers in order of importance were operative time, length of stay and consumables. To achieve cost equivalence with RRP, operative times would need to average 159 minutes (LRP and PLND) and 174 minutes (LRP alone) holding other factors constant. Cost equivalence could not be achieved by shortening hospital stay alone unless LRP were performed as an outpatient procedure. CONCLUSIONS: Our model predicts the perioperative costs of LRP to be greater than RRP by a factor of less than 1.2x. If disposable instruments and trocars are eliminated, and patients undergoing LRP and PLND are discharged on postoperative day 2, cost equivalence with RRP and PLND can be achieved with operative times of 3.4 hours.

Computer Simulation↗