Focal high-intensity focused ultrasound therapy for localized prostate cancer: An interim analysis of the multinational FASST study.

BACKGROUND: High-intensity focused ultrasound (HIFU) emerged as a novel approach for the treatment of localized prostate cancer (PCa). However, prospective studies on HIFU-related outcomes and predictors of treatment failure (TF) remain scarce. MATERIALS AND METHODS: We conducted a multinational prospective cohort study among patients undergoing HIFU therapy for localized, low- to intermediate-risk PCa. Follow-up data on serial prostate specific antigen (PSA), multi-parametric magnetic resonance imaging (mpMRI), targeted/systematic biopsies, adverse events and functional outcomes were collected. The primary endpoint was TF, defined as histologically confirmed PCa requiring whole-gland salvage treatment. Uni- and multi-variable adjusted hazard ratios (HRs) were calculated using Cox proportional hazard regression models. RESULTS: At baseline, mean (standard deviation) age was 64.14 (7.19) years, with the majority of patients showing T-stage 1 (73.9%) and International Society of Urological Pathology grading system Grade 2 (58.8%). PSA nadir (median, 1.70 ng/mL) was reached after 6 months. Of all patients recruited, 16% had clinically significant PCa, as confirmed by biopsy, of which 13.4% had TF. Notably, T-stage and number of positive cores at initial biopsy were independent predictors of TF during follow-up (HR [95% CI] 1.27 [1.02-1.59] and 5.02 [1.80-14.03], respectively). Adverse events were minimal (17% and 8% early and late adverse events, respectively), with stable or improved functional outcomes in the majority of patients. CONCLUSIONS: This interim analysis of a multinational study on HIFU therapy for the management of low-to-intermediate-risk PCa reveals good functional outcomes, minimal adverse events and low incidence of TF over the short-term. Data on long-term outcomes, specifically as it relates to oncological outcomes, are awaited eagerly.

Evaluation of Image Quality of Overweight and Obese Patients in CT Using High Data Rate Detectors.

BACKGROUND/AIM: To evaluate the impact of high data rate and sampling frequency detector technology compared to standard scan equipment on the image quality in abdominal computed tomography (CT) of overweight and obese patients. PATIENTS AND METHODS: A total of 173 patients were retrospectively included in this study. Objective image quality in abdominal CT was evaluated using comparative analysis with new detector technology prior to market launch and standard CT equipment. Contrast noise ratio (CNR), image noise, volumetric computed tomography dose index (CTDIVol), and figures of merit (Q and Q1) were assessed for all patients. RESULTS: Image quality was superior in the new detector technology for all parameters evaluated. The dose dependent parameters Q and Q1 showed a significant difference (p<0.001). CONCLUSION: A significant increase in objective image quality could be demonstrated using a new generation detector setup with increased frequency transfer in abdominal CT of overweight patients.

Quantifying and Statistically Modeling Residual Pneumoperitoneum after Robotic-Assisted Laparoscopic Prostatectomy: A Prospective, Single-Center, Observational Study.

BACKGROUND: Laparoscopic surgery (LS) requires CO2 insufflation to establish the operative field. Patients with worsening pain post-operatively often undergo computed tomography (CT). CT is highly sensitive in detecting free air-the hallmark sign of a bowel injury. Yet, the clinical significance of free air is often confounded by residual CO2 and is not usually due to a visceral injury. The aim of this study was to attempt to quantify the residual pneumoperitoneum (RPP) after a robotic-assisted laparoscopic prostatectomy (RALP). METHODS: We prospectively enrolled patients who underwent RALP between August 2018 and January 2020. CT scans were performed on postoperative days (POD) 3, 5, and 7. To investigate potential factors influencing the quantity of RPP, correlation plots were made against common variables. RESULTS: In total, 31 patients with a mean age of 66 years (median 67, IQR 62-70.5) and mean BMI 26.59 (median 25.99, IQR: 24.06-29.24) underwent RALP during the study period. All patients had a relatively unremarkable post-operative course (30/31 with Clavien-Dindo class 0; 1/31 with class 2). After 3, 5, and 7 days, 3.2%, 6.4%, and 32.3% were completely without RPP, respectively. The mean RPP at 3 days was 37.6 mL (median 9.58 mL, max 247 mL, IQR 3.92-31.82 mL), whereas the mean RPP at 5 days was 19.85 mL (median 1.36 mL, max 220.77 mL, IQR 0.19-5.61 mL), and 7 days was 10.08 mL (median 0.09 mL, max 112.42 mL, IQR 0-1.5 mL). There was a significant correlation between RPP and obesity (p = 0.04665), in which higher BMIs resulted in lower initial insufflation volumes and lower RPP. CONCLUSIONS: This is the first study to systematically assess RPP after a standardized laparoscopic procedure using CT. Larger patients tend to have smaller residuals. Our data may help surgeons interpreting post-operative CTs in similar patient populations.

The Role of New Technologies in the Diagnosis and Surveillance of Non-Muscle Invasive Bladder Carcinoma: A Prospective, Double-Blinded, Monocentric Study of the XPERT© Bladder Cancer Monitor and Narrow Band Imaging© Cystoscopy.

Follow-up is essential for the early detection of recurrent non-muscle invasive bladder cancers (NMIBC). This study investigates the clinical relevance of new diagnostic tools such as an mRNA-based urine test (XPERT© Bladder Cancer Monitor, XBCM) and Narrow Band Imaging© (NBI) and compares them with the established follow-up diagnostics (white-light cystoscopy (WLC) and urine cytology). This was a prospective, double-blind, single-center study that involved patients undergoing NMIBC screening at a tertiary care center. Enrollment occurred between January 2018 and March 2020. In addition to standard care (WLC, cytology, and ultrasound), patients underwent XBCM urine testing and NBI cystoscopy. In total, 301 WLCs were performed; through this, 49 patients demonstrated NMIBC recurrence. NBI cystoscopy was congruent with WLC in all patients. Cytology showed a sensitivity (SE) and specificity (SP) of 27% and 97% (PPV: 65%; NPV 87%), respectively, whereas XBCM showed SE and SP of 58% and 89%, respectively (PPV: 51%; NPV: 92%; AUC: 0.79 (0.716-0.871)). Subgroup analysis showed improved SE and similar SP (PPV, NPV) for high grade (HG) recurrence, with a SE of 74% and SP of 89% (39%, 97%). NBI cystoscopy does not necessarily provide additional benefit over standard WLC. However, the XBCM may provide better SE and a diagnostic advantage in instances of HG disease recurrence.

The role of donor age and gender in the success of human muscle precursor cell transplantation.

Autologous cell transplantation for the treatment of muscle damage is envisioned to involve the application of muscle precursor cells (MPCs) isolated from adult skeletal muscle. At the onset of trauma, these cells are recruited to proliferate and rebuild injured muscle fibres. However, a variety of donor-specific cues may directly influence the yield and quality of cells isolated from a muscle biopsy. In this study, we isolated human MPCs and assessed the role of donor gender and age on the ability of these MPCs to form functional bioengineered muscle. We analysed the cell yield, growth and molecular expression in vitro, and the muscle tissue formation and contractility of the bioengineered muscle, from cells isolated from men and women in three different age groups: young (20-39 years), adult (40-59 years) and elderly (60-80 years). Our results suggest that human MPCs can be successfully isolated and grown from patients of all ages and both genders. However, young female donors provide fast-growing cells in vitro with an optimum contractile output in vivo and are therefore an ideal cell source for muscle reconstruction. Taken together, these findings describe the donor-related limitations of MPC transplantation and provide insights for a straightforward and unbiased clinical application of these cells for muscle reconstruction. Copyright © 2014 John Wiley & Sons, Ltd.

Urinary Incontinence-85: An Expanded Prostate Cancer Composite (EPIC) Score Cutoff Value for Urinary Incontinence Determined Using Long-term Functional Data by Repeated Prospective EPIC-Score Self-assessment After Radical Prostatectomy.

PURPOSE: To determine an objective cutoff value (COV) for urinary incontinence (UI) using the Expanded Prostate Cancer Composite (EPIC) score after radical prostatectomy (RP). METHODS: From 2004-2013, all RP patients at our institution completed the EPIC urinary domain (EPIC-UD) questionnaire preoperatively and 6 weeks; 3, 6, 9, 12, and 18 months postoperatively; and yearly thereafter. The EPIC-UD is composed of several questions, 4 of which address UI qualitatively (EPIC-UI). Furthermore, patients were asked to complete a global quality of life (QoL) questionnaire regarding continence. The EPIC COV was calculated using receiver operating characteristic (ROC) analysis. Correlations between the EPIC-UI and quantitative QoL were evaluated using the Kendall-Tau test. RESULTS: We analyzed 239 patients with a median age of 63 years (interquartile range [IQR], 59-66 years), a median follow-up of 48 months (IQR, 30-78 months) and a median preoperative EPIC-UI score of 100 (IQR, 91.75-100). The ROC analysis for the distinction between EPIC-UI and the use of ≤1 pad/day yielded an EPIC-UI COV of >85, which we termed the UI-85, with an area under the curve of 0.857 (P<0.0001). A stronger correlation was seen between QoL scores and the UI-85 (1 year postoperatively: correlation coefficient [CC], 0.592; P<0.0001) than between QoL and not using a pad (CC, 0.512; P<0.0001). CONCLUSIONS: The calculated COV of the EPIC-UI for continence was 85. UI is a multidimensional condition that cannot be adequately characterized by a single piece of information, such as pad usage only. Hence, the UI-85 represents a nuanced and straightforward tool for monitoring and comparing continence between different time points and cohorts in a multidimensional and objective manner.

The impact of the 2005 International Society of Urological Pathology Gleason grading consensus on active surveillance for prostate cancer.

INTRODUCTION: Current treatment plans for localized prostate carcinoma (PC) are based on core needle biopsies (CNB) classified using the Gleason score (GS). Recently, many institutions have started using the latest version of International Society of Urological Pathology (ISUP) guideline revision from 2014 for PC grading. Interestingly, this adoption is occurring without first understanding whether the 2005 ISUP revisions had a positive clinical impact. CNB-based GS may underestimate tumor aggressiveness and, therefore, critically impact patient eligibility for active surveillance (AS). The 2005 ISUP recommendations bore a significant impact on the grading of Gleason 6 and 7 PCs - a range that is meaningful for AS. The objective of this study was to compare the concordance between GS in CNB and radical prostatectomy (RP) before and after the 2005 ISUP guideline revisions, with an emphasis on its clinical impact on AS. MATERIAL AND METHODS: This was a single-center, prospective observational study. CNB were performed in a standardized manner. GS of CNB and RP specimens were compared across three time periods: 1999-2005 (pre-revision), 2006-2007 (transitional period), and 2008-2015 (post-revision). AS is usually employed in patients with GS 6 or GS 7 PC. Thus, we therefore focused on the analysis of patients with CNBs of GS ≤7. RESULTS: Between 1999 and 2015, 380 men with GS ≤7 PC underwent RP at our institution (median age: 62y; median PSA: 5.8 ng/ml). Of these, 231 CNB specimens were classified as GS ≤6, while 149 were GS 7.46% (pre-revision), 43% (transitional), and 54% (post-revision) of CNB with original scores ≤6 were later upgraded in corresponding RP specimens (p <0.001). CONCLUSIONS: The 2005 ISUP GS revisions did not lower the rates of GS upgrades in RP specimens when compared to corresponding initial CNBs. Thus, these revisions did not improve AS selection. Future advances in molecular diagnostics may provide additional valuable information that facilitates patient enrollment in AS programs.

Prostate volume reduction following pure transurethral bipolar plasma vaporization and conventional transurethral resection of the prostate: a prospective investigation using transrectal 3D ultrasound volumetry.

PURPOSE: To evaluate and compare postoperative changes in prostate volume and clinical outcome after bipolar plasma vaporization (BPV) and conventional transurethral resection of the prostate (TURP). PATIENTS AND METHODS: Consecutive series of patients undergoing BPV or TURP were included in this prospective, nonrandomized study. Planimetric volumetry after transrectal three-dimensional ultrasound of the prostate was performed preoperatively and postoperatively after 6 weeks, 6 months and 12 months. Additionally, changes in clinical outcome parameters were assessed and compared between the groups. The reduction ratio and analysis of covariance were used to compare volume changes between BPV and TURP. Multiple regression analysis was performed to assess a possible interaction between preoperative prostate volume and effect of therapy. RESULTS: A total of 157 patients were included (BPV: n = 68, TURP: n = 89). Median preoperative prostate volume was 43.1 ml in the BPV group and 45.9 ml in the TURP group (p = 0.43). Postoperatively, the prostate volumes decreased significantly in both groups. After catheter removal, the relative residual prostate volume was significantly higher in the BPV group (66.6 vs. 60.8 %; p = 0.02). Thereafter, significant differences were not detectable anymore (12 months: 46.6 vs. 47.1 %; p = 0.82). Regression analysis revealed that tissue ablation after BPV was superior to TURP in prostates <45 ml but inferior in prostates >45 ml. All clinical outcome parameters improved significantly and were not significantly different between the groups. CONCLUSIONS: Volume reduction and short-term clinical outcome following pure BPV was excellent and comparable to conventional TURP. However, volume reduction seems to be limited in patients with larger prostates.

Acknowledging unreported problems with active surveillance for prostate cancer: a prospective single-centre observational study.

OBJECTIVE: To report outcomes of patients with localised prostate cancer (PCa) managed with active surveillance (AS) in a standard clinical setting. DESIGN: Single-centre, prospective, observational study. SETTING: Non-academic, average-size hospital in Switzerland. PARTICIPANTS: Prospective, observational study at a non-academic, average-size hospital in Switzerland. Inclusion and progression criteria meet general recommendations. 157 patients at a median age of 67 (61-70) years were included from December 1999 to March 2012. Follow-up (FU) ended June 2013. RESULTS: Median FU was 48 (30-84) months. Overall confirmed reclassification rate was 20% (32/157). 20 men underwent radical prostatectomy with 1 recurrence, 11 had radiation therapy with 2 prostate-specific antigen relapses, and 1 required primary hormone ablation with a fatal outcome. Kaplan-Meier estimates for those remaining in the study showed an overall survival of 92%, cancer-specific survival of 99% and reclassification rate of 41%. Dropout rate was 36% and occurred at a median of 48 (21-81) months after inclusion. 68 (43%) men are still under AS. CONCLUSIONS: Careful administration of AS can and will yield excellent results in long-term management of PCa, and also helps physicians and patients alike to balance quality of life and mortality. Our data revealed significant dropout from FU. Patient non-compliance can be a relevant problem in AS.

Absorption of irrigation fluid occurs frequently during high power 532 nm laser vaporization of the prostate.

PURPOSE: Absorption of irrigation fluid was not detected during GreenLight™ laser vaporization of the prostate using the first generation 80 W laser. However, data are lacking on intraoperative irrigation fluid absorption using the second generation 120 W high power laser. We assessed whether fluid absorption occurs during high power laser vaporization of the prostate. MATERIALS AND METHODS: We performed this prospective investigation at a tertiary referral center in patients undergoing 120 W laser vaporization for prostatic bladder outlet obstruction. Normal saline containing 1% ethanol was used for intraoperative irrigation. The expired breath ethanol concentration was measured periodically during the operation using an alcometer. The volume of saline absorption was calculated from these concentrations. Intraoperative changes in hematological and biochemical blood parameters were also recorded. RESULTS: Of 50 investigated patients 22 (44%) had a positive breath ethanol test. Median absorption volume in the absorber group was 725 ml (range 138 to 3,452). Ten patients absorbed more than 1,000 ml. Absorbers had a smaller prostate, more capsular perforation, higher bleeding intensity and more laser energy applied during the operation. Three patients (13%) had symptoms potentially related to fluid absorption. Hemoglobin, hematocrit and serum chloride were the only blood parameters that changed significantly in the absorber group. The changes were significantly different than those in nonabsorbers. CONCLUSIONS: Fluid absorption occurs frequently during high power laser vaporization of the prostate. This should be considered in patients who present with cardiopulmonary or neurological symptoms during or after the procedure.

Ablative efficiency of 532-nm laser vaporization compared to transurethral resection of the prostate: results from a prospective three-dimensional ultrasound volumetry study.

PURPOSE: To assess and compare postoperative prostate volume changes following 532-nm laser vaporization (LV) and transurethral resection of the prostate (TURP). To investigate whether differences in volume reduction are associated with differences in clinical outcome. METHODS: In this prospective, non-randomized study, 184 consecutive patients undergoing 120 W LV (n = 98) or TURP (n = 86) were included. Transrectal three-dimensional ultrasound and planimetric volumetry of the prostate were performed preoperatively, after catheter removal, 6 weeks, 6 and 12 months. Additionally, clinical outcome parameters were recorded. Mann-Whitney U test and analysis of covariance were utilized for statistical analysis. RESULTS: Postoperatively, a significant prostate volume reduction was detectable in both groups. However, the relative volume reduction was lower following LV (18.4 vs. 34.7 %, p < 0.001). After 6 weeks, prostate volumes continued to decrease in both groups, yet differences between the groups were less pronounced. Nonetheless, the relative volume reduction remained significantly lower following LV (12 months 43.3 vs. 50.3 %, p < 0.001). All clinical outcome parameters improved significantly in both groups. However, the maximum flow rate (Q max) and prostate-specific antigen (PSA) reduction were significantly lower following LV. Subgroup analyses revealed significant differences only if the initial prostate volume was >40 ml. Re-operations were necessary in three patients following LV. CONCLUSIONS: The modest but significantly lower volume reduction following LV was associated with a lower PSA reduction, a lower Q max and more re-operations. Given the lack of long-term results after LV, our results are helpful for preoperative patient counseling. Patients with large prostates and no clear indication for the laser might not benefit from the procedure.

Lateral temperature spread of monopolar, bipolar and ultrasonic instruments for robot-assisted laparoscopic surgery.

OBJECTIVE: To assess critical heat spread of cautery instruments used in robot-assisted laparoscopic (RAL) surgery. MATERIALS AND METHODS: Thermal spread along bovine musculofascial tissues was examined by infrared camera, histology and enzyme assay. Currently used monopolar, bipolar and ultrasonic laparoscopic instruments were investigated at various power settings and application times. The efficacy of using an additional Maryland clamp as a heat sink was evaluated. A temperature of 45 °C was considered the threshold temperature for possible nerve damage. RESULTS: Monopolar instruments exhibited a mean (sem) critical thermal spread of 3.5 (2.3) mm when applied at 60 W for 1 s. After 2 s, the spread was >20 mm. For adjustable bipolar instruments the mean (sem) critical thermal spread was 2.2 (0.6) mm at 60 W and 1 s, and 3.6 (1.3) mm at 2 s. The PK and LigaSure forceps had mean (sem) critical thermal spreads of 3.9 (0.8) and 2.8 (0.6) mm respectively, whereas the ultrasonic instrument reached 2.9 (0.8) mm. Application of an additional Maryland clamp as a heat sink, significantly reduced the thermal spread. Histomorphometric analyses and enzyme assay supported these findings. CONCLUSIONS: All coagulation devices used in RAL surgery have distinct thermal spreads depending on power setting and application time. Cautery may be of concern due to lateral temperature spread, causing potential damage to sensitive structures including nerves. Our results provide surgeons with a resource for educated decision-making when using coagulation devices during robotic procedures.

Prospective evaluation of irrigation fluid absorption during pure transurethral bipolar plasma vaporisation of the prostate using expired-breath ethanol measurements.

OBJECTIVES: To investigate if absorption of irrigation fluid occurs during bipolar plasma vaporisation (BPV) of the prostate. To examine the clinical predictors of increased risk of fluid absorption and to assess if changes in serum electrolytes, venous pH, haemoglobin or haematocrit are able to detect intra-operative fluid absorption. PATIENTS AND METHODS: Over a 15-month period, 55 consecutive patients undergoing BPV of the prostate were investigated. The volume of intra-operative fluid absorption was measured using expired-breath ethanol measurements. Intra-operative irrigation was performed with isotonic saline containing 1% ethanol. The breath ethanol concentration was measured every 10 min during the operation and the volume of irrigation fluid absorption was calculated from these concentrations. Data on clinical (age, prostate volume, smoking status) and surgical variables (operation time, irrigation volume, appearance of capsular perforation) as well as intra-operative changes in serum electrolytes, venous pH, haemoglobin and haematocrit were recorded. RESULTS: The median (range) age of the patients was 67 (48-87) years and the median (range) prostate volume was 41 (17-111) mL. Nine patients (16%) showed a positive ethanol breath test during the procedure. The median (range) calculated fluid absorption in these patients was 346 (138-2166) mL. Three patients had a fluid absorption >500 mL. One patient with absorption of >2 L showed clinical symptoms (dyspnoea and agitation) during the operation under spinal anaesthesia. In the group of patients with fluid absorption, capsular perforation or injury to larger vessels was more often detectable. In the group of patients with fluid absorption, only venous pH showed a significant change during the operation (from median 7.41 to median 7.34, P = 0.02). The pH decrease was significantly greater in the fluid absorption group than in the group of patients without fluid absorption (0.09 vs. 0.02, P = 0.005). CONCLUSION: We have demonstrated that significant intra-operative fluid absorption can occur during BPV of the prostate. Care must be taken if using this procedure in patients with significant cardiovascular comorbidities. Respecting the anatomical borders of the prostate seems to play a relevant role in preventing fluid absorption during the procedure. Venous pH could be used to detect potentially dangerous fluid absorption if intra-operative monitoring with breath ethanol measurements is not available.

Continuous low-dose aspirin therapy in robotic-assisted laparoscopic radical prostatectomy does not increase risk of surgical hemorrhage.

BACKGROUND: Withdrawal of oral antiplatelet therapy (OAT) is a major risk factor for stent thrombosis, myocardial infarction, and cerebral strokes. In order to minimize the risk for thrombotic complications, since 2007 robotic-assisted laparoscopic radical prostatectomy (RARP) has taken place under continuous OAT with aspirin at our institution. In this retrospective study we analyzed the risk for perioperative bleeding and surgical outcome after RARP with OAT. PATIENTS AND METHODS: All patients who underwent RARP with aspirin OAT at our institution since 2007 were included in this analysis. The OAT group was compared with a group that underwent RARP without OAT, which contained twice the number of patients. Matching of the two groups was performed with regard to the tumor stage and whether a lymph node dissection or nerve-sparing was performed. RESULTS: Thirty-eight patients were assigned to the OAT group and 76 to the control group. A difference in the decrease of postoperative hemoglobin concentration was not detectable between the two groups (mean drop of 2.9±1.4 g/dL and 2.9±1.1 g/dL, respectively; P=.93). RARP was completed in all OAT patients without conversion to open surgery. Two of the 38 patients (5.3%) in the OAT group and none in the control group required blood transfusions (P=.11). Equivalent rates of positive surgical margins for pT2 tumors were detected (16% OAT versus 14% control group; P=1.0). No adverse cardiovascular events occurred in either group during the hospitalization. CONCLUSIONS: Continued perioperative OAT with aspirin in RARP is safe, feasible, and not associated with increased blood loss.

Thermal spread of vessel-sealing devices evaluated in a clinically relevant in vitro model.

INTRODUCTION: Bipolar vessel-sealing devices (VSDs) have advantages in urological surgeries (less hemorrhage, shorter operating time). However, these instruments can cause thermal injuries, which can result in neural damage and necrosis. The objectives of this study were to establish a reproducible in vitro model for standardized assessment of electrosurgical devices and to evaluate whether optimized placement of surgical instruments can reduce the thermal spread. METHODS: We evaluated thermal spread of two VSDs in vitro using thin bovine muscle strips. Thermal injury was measured using an infrared camera, temperature probes and histology. The recordings were made with the VSD alone and with a rectangular clamp next to the VSD. RESULTS: Both instruments showed a significant temperature spread of 2.5 mm lateral to the VSD. The placement of a metal clamp next to the VSD significantly reduced the temperature spread. Histological examinations were able to underline these findings. CONCLUSIONS: In this study we describe a straightforward clinically relevant in vitro model for the evaluation of future electrosurgical instruments. We demonstrated that the thermal spread of VSD could be further reduced by optimized placement of an additional surgical instrument. Our results could help surgeons protect sensitive structures like nerves in the vicinity of the VSD.

Lithium triborate laser vaporization of the prostate using the 120 W, high performance system laser: high performance all the way?

PURPOSE: Technical modifications of the 120 W lithium-triborate laser have been implemented to increase power output, and prevent laser fiber degradation and loss of power output during laser vaporization of the prostate. However, visible alterations at the fiber tip and the subjective impression of decreasing ablative effectiveness during lithium-triborate laser vaporization indicate that delivering constantly high laser power remains a relevant problem. Thus, we evaluated the extent of laser fiber degradation and loss of power output during 120 W lithium-triborate laser vaporization of the prostate. MATERIALS AND METHODS: We investigated 46 laser fibers during routine 120 W lithium-triborate laser vaporization in 35 patients with prostatic bladder outflow obstruction. Laser beam power was measured at baseline and after the application of each 25 kJ during laser vaporization. Fiber tips were microscopically examined after the procedure. RESULTS: Mild to moderate degradation at the emission window occurred in all fibers, associated with a loss of power output. A steep decrease to a median power output of 57.3% of baseline was detected after applying the first 25 kJ. Median power output at the end of the defined 275 kJ lifespan of the fibers was 48.8%. CONCLUSIONS: Despite technical refinements of the 120 W lithium-triborate laser fiber degradation and significantly decreased power output are still detectable during the procedure. Laser fibers are not fully appropriate for the high power delivery of the new system. There is still potential for further improvement in the laser performance.

Intra-abdominal fire due to insufflating oxygen instead of carbon dioxide during robot-assisted radical prostatectomy: case report and literature review.

We report the first case of intra-abdominal combustion involving the plastic covering of monopolar scissors secondary to use of incorrect gas (oxygen [O(2)] instead of carbon dioxide [CO(2)]) during robot-assisted laparoscopic radical prostatectomy (RALP). The insufflating system was connected to a provisional O(2) gate into the operating theater. A patient underwent RALP and extended pelvic lymph node dissection for localized prostate cancer, according to standard technique. Approximately 1.5 h after the start of surgery, flames arose from the scissor tips during monopolar coagulation. After extinguishing the fire, we promptly withdrew and changed instruments before recognizing and resolving the cause of the incident. The procedure was carried out without patient injury, and the postoperative period was uneventful.