Surgical Parameters Related to Excessive Intrarenal Pressure during Minimally Invasive Percutaneous Nephrolithotomy in the Supine Position: A Prospective Observational Clinical Study.

Objective: Excessive intrarenal pressure (IRP) during surgery for renal stones is related to postoperative complications due to systemic absorption of bacteria and endotoxins. This study is aimed at evaluating factors that induce excessive IRP in minimally invasive percutaneous lithotripsy (mini-PCNL) in the supine position. Methods: 27 patients underwent mini-PCNL for intrarenal stones under supine position and were analyzed in this study. The IRP changes were measured at the phases of "baseline," "table tilting," "upper-pole navigation," "stone fragmentation," and "vacuum cleaning effect." The relationship between the mean IRP and cumulative time of IRP ≥ 30 cmH2O was analyzed by according to the surgical parameters. Multiple regression analysis showed the effect of the surgical parameters on postoperative fever-related IRP elevation. Results: Mean age was 59.3 ± 14.6 years. The mean stone burden was 24.6 ± 8.1 mm3. IRP was higher than baseline (31.6 ± 12.1) during upper-pole navigation (60.0 ± 22.9, p = 0.003) and stone fragmentation (46.2 ± 9.9, p < 0.001). The subgroup's IRP baseline < 20 cmH2O significantly increased during the upper-pole navigation. Changes in IRP at each stage were affected by baseline IRP (p < 0.001), operation methods (p = 0.021), number of calyces with stones (p = 0.034), and laser energy of Joules (p = 0.041) and frequency (p = 0.038). Conclusion: In supine mini-PCNL, the IRP was higher during laser fragmentation and upper-pole navigation. The table tilting procedure can be helpful in selected patients. The vacuum cleaner effect did not affect IRP.

A presumptive role of lower ureteral angles in the difficulty of ureteral access sheath insertion during retrograde intrarenal surgery.

PURPOSE: We aimed to investigate whether the angle created by the most lateral portion of the lower ureter is responsible for the difficulty in ureteral access sheath insertion. METHODS: All male patients scheduled to undergo flexible ureteroscopy were enrolled. Patients with ureteral stricture in any course of the ureter and patients with problems at the ureteral opening were excluded. We set the coordinates of the most lateral portion of the lower ureter as M (x, y, z) using computed tomography. The bladder outlet was marked as the zero point O (0, 0, 0). The vector that passed through the urethra and point O was expressed as Vuo (0, 0, - u). The vector that passed through points O and M was expressed as Vom (x, y, z). Thus, an angle (90° - α) could be calculated between Vuo and Vom using the rotation angle formula. RESULTS: A total of 671 male patients were enrolled, among whom the ureteral access sheath could not pass through the most lateral portion of the lower ureter in 14 patients. The mean values of the α angle were 38.56° and 48.48° in the patient and control groups, respectively, compared with the 42 age- and sex-matched control subjects (p < 0.001). CONCLUSION: The ureteral angle determined by the level of the bladder outlet and the most lateral portion of the lower ureter could be a causative factor for the failure of ureteral access sheath insertion.

Bipolar enucleation of the prostate-step by step.

Bipolar enucleation of prostate (BipolEP) is a useful method for treatment of benign prostatic hyperplasia (BPH). Compared with conventional transurethral resection, the enucleation technique has several advantages. However, since the cost of laser equipment used for enucleation is relatively high, enucleation using bipolar devices has been attempted by many previous surgeons. We consider bipolar enucleation is an effective and safe procedure, and we would like to share our experience of equipment settings and procedures through this article. We will introduce the equipment and settings of BipolEP and then present the actual step-by-step procedures and surgical tips. First, circular incisions are made on bladder neck and mucosa at the level of verumontanum. Then, enucleation is performed in the order of median and lateral lobes as in laser enucleation. Haemostasis should be done throughout the procedure. After enucleation and haemostasis, prostatic tissue is evacuated by morcellator. Currently, there are several types of electrode and morcellator systems. In our experience, BipolEP has a steep learning curve but it is safe and effective procedure for managing BPH. In particular, effective haemostasis is the greatest advantage of BipolEP when compared to traditional TUR or laser enucleation.

How to reduce 'double-firing'-induced scope damage by investigating the relationship between laser fiber core degradation and fiber jacket burn?

PURPOSE: 'Double-firing effect' in which laser firing occurs in the fiber tip and its proximal part is caused by different breakdown rates between fiber jackets and cores. This study investigated a new safe distance concept to prevent scope damage by analyzing the breakdown of the laser fiber jacket and cores. METHODS: Laser fibers were fixed in a benchtop simulation model. The fiber tip was in contact with uniform phantom stones and submerged in saline. Four different energy settings (1.0 or 2.0J x 10Hz or 30Hz) and two different fiber sizes (200 µm and 365 µm) were tested. After three minutes of use at each energy setting, the length of fiber shortening and jacket burn were measured. The fibers were stripped to measure the length of core degradation. RESULTS: Mean degradation lengths were 4.2 to 7.8 mm. There was no statistical difference in the mean lengths of fiber core degradation and jacket burn. However, core degradation was longer than the jacket burn in half of the samples. The mean difference in lengths between core degradation and jacket burn was 0.49 ± 0.90 mm. Lengths of core degradation and the jacket burn were longer at the setting of high-power energy and 200 µm fiber - 2J with 30 Hz. CONCLUSION: To reduce 'double-firing'-induced damage, the authors recommend that laser fiber should be cut 1.0 mm longer than visible jacket burn at high-power settings after 3-min continuous fragmentation. After cutting the fiber, the laser should be checked whether 'double-firing' is no more seen.

Postoperative renal functional changes assessed by 99mTc-DTPA scintigraphy and predictive factors after miniaturized percutaneous nephrolithotomy and retrograde intrarenal surgery: An observational 1-year follow-up study.

Purpose: We evaluated the comparative effect of miniaturized percutaneous nephrolithotomy (mini-PCNL) and retrograde intrarenal surgery (RIRS) on perioperative kidney function by use of diethylenetriamine penta-acetic acid (99mTc-DTPA) scintigraphy and identified significant predictors associated with deterioration or amelioration of renal function after surgery. Materials and Methods: All 70 patients who underwent mini-PCNL or RIRS between 2012 and 2016 were monitored by 99mTc-DTPA scintigraphy preoperatively. Patients with abnormal renal function were monitored from 3 to 12 months postoperatively. Logistic regression analyses were conducted to estimate the predictors of aggravated renal dysfunction and improvement. Results: The difference in preoperative renal function between the contralateral and the operative side was >10% in 57 patients (81.4%). Among those in the group with abnormal renal function, 40 (70.2%), 10 (17.5%), and 7 (12.3%) patients showed stability, deterioration, and improvement in renal function at postoperative year 1, respectively. Functional changes did not differ according to the type of surgery. A high level of serum creatinine preoperatively (p=0.060) and a history of previous stone procedures (p=0.051) showed borderline significance for prediction of deterioration in renal function. Conclusions: RIRS and mini-PCNL had similar effects and favorable outcomes on renal function during a 1-year follow-up period. High baseline serum creatinine levels and a history of procedures warrant careful attention.

Influence of anesthesia methods on surgical outcomes and renal function in retrograde intrarenal stone surgery: a prospective, randomized controlled study.

BACKGROUND: We analyzed the influence of anesthesia methods on surgical outcomes and renal function in retrograde intrarenal surgery (RIRS) in a prospective, randomized controlled study. METHODS: Seventy patients who underwent RIRS from September 2015 to February 2017 were randomly allocated to general anesthesia (GA) or spinal anesthesia (SA) groups. Renal function was assessed using estimated glomerular filtration rate, and separate renal function was evaluated using nuclear medicine tests. Maneuverability and accessibility were evaluated after every surgery. All procedures were performed by a single experienced surgeon (SY Cho). RESULTS: Stone-free rate was higher in the GA (92.3%, 36 of 39) than the SA (71.0%, 22 of 31) (P = 0.019) group. Pain score was higher in the GA than in the SA group on the first postoperative morning (P = 0.025), but pain scores of the two groups were similar before discharge (P = 0.560). There were no differences in the changes of serum creatinine level (P = 0.792) and changes of estimated glomerular filtration rate (P = 0.807). Differences of separate renal function between operative and contralateral site increased significantly in patients under GA than under SA at postoperative 3 months (P = 0.014). Maneuverability and accessibility were better in SA with sedation than GA (P < 0.001). CONCLUSIONS: RIRS under SA showed advantages in renal function change using renogram at postoperative 3 months and in lower pain score on the first postoperative morning. Performance of operator under SA was worse than that under GA and significantly improved with sedation. RIRS under SA showed advantages in lower pain score at postoperative first day. TRIAL REGISTRATION: Clinicaltrials.gov ID is NCT03957109, and registration date is 17th May 2019. This study was retrospectively registered.

The incidence and histological characteristics of intratubular germ cell neoplasia in postpubertal cryptorchid testis.

PURPOSE: It is well known that testicular germ cell tumors arise with increased frequency in patients with cryptorchidism. In addition, intratubular germ cell neoplasia (ITGCN) is a precursor lesion to testicular germ cell tumor. Approximately 50% of patients with ITGCN will develop an invasive of testicular germ cell tumors within 5 years. Therefore, we evaluated that the incidence of ITGCN in postpubertal cryptorchidism. MATERIALS AND METHODS: Between January 2002 and August 2012, orchiectomy specimens from 31 postpubertal patients (aged 12 or over) with cryptorchid testis were reviewed. The specimens were evaluated for ITGCN using immunohistochemical stains of placental-like alkaline phosphatase and Oct 3/4 with routine hematoxylin-eosin stain. Additionally, the degree of spermatogenesis was assessed using the Johnsen score. RESULTS: Mean age was 34 years (range, 17 to 74 years) at surgery. All patients were diagnosed as unilateral cryptorchidism. One patient (3.2%) of 20-year-old had ITGCN in surgical specimen with all positive markers. Histological assessment of spermatogenesis showed that mean Johnsen score was 3.42 (range, 1 to 9). Majority of patients (27 of 31) presented impaired spermatogenesis with low Johnsen score lesser than 5. CONCLUSIONS: Considering the risk of malignancy and low spermatogenesis, we should perform immunohistochemical stains and discuss preventative orchiectomy for the postpubertal cryptorchidism.

Clinical significance of national institutes of health classification in patients with chronic prostatitis/chronic pelvic pain syndrome.

PURPOSE: We determined the effects of alpha-blockers and quinolone in patients with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) classified by National Institute of Health (NIH) consensus group. MATERIALS AND METHODS: Data from a total of 111 patients who were diagnosed with CP/CPPS between June 2010 and June 2012 were analyzed retrospectively. The patients were classified into group 1 (category IIIA, n=40) and group 2 (category IIIB, n=71). Treatment using alfuzosin and levofloxacin was given to both groups for 6 weeks. International Prostate Symptom Score (IPSS) and NIH Chronic Prostatitis Symptom Index were measured before and after therapy. RESULTS: Group 1 had a significant decrease in total IPSS score, CPSI pain score, CPSI quality of life (QoL) score, and total CPSI score (p=0.043, p=0.006, p=0.015, and p=0.006, respectively). Group 2 had a significant decrease in IPSS voiding symptom score, IPSS storage symptom score, total IPSS, CPSI pain score, CPSI voiding score, CPSI QoL score, and total CPSI score (p=0.002, p=0.004, p=0.001, p=0.001, p=0.006, p=0.001, and p=0.001, respectively). The CPSI score was reduced by 6 points or more in 50.0% of patients (n=18) in group 1 and in 51.6% of patients (n=32) in group 2. However, there was no statistically significant difference between the changes in IPSS and CPSI scores across the 2 groups. CONCLUSIONS: Although combination treatment reduced the CPSI score in both groups, there was no significant difference between the groups after combination treatment. We suggest that factors other than inflammation also contribute to symptoms associated with CP/CPPS.