Usefulness of LacdiNAc-glycosylated Prostate-specific Antigen Density for Predicting Pathological Findings of Magnetic Resonance Imaging-transrectal Ultrasound Fusion Image-guided Prostate Biopsy for the Patients With Highest Prostate Imaging Reporting and Data System Category ≥3.

PURPOSE: This study aimed to evaluate the usefulness of the LDN-PSA (LacdiNAc-glycosylated-prostate specific antigen) in detecting clinically significant prostate cancer in patients suspected of having clinically significant prostate cancer on multiparametric magnetic resonance imaging. MATERIALS AND METHODS: Patients with prostate specific antigen levels ranging between 3.0 ng/mL and 20 ng/mL and suspicious lesions with PI-RADS (Prostate Imaging-Reporting and Data System) category ≥3 were included prospectively. The LDN-PSA was measured using an automated 2-step Wisteria floribunda agglutinin lectin-anti-prostate specific antigen antibody sandwich immunoassay. RESULTS: Two hundred four patients were included. Clinically significant prostate cancer was detected in 105 patients. On multivariable logistic regression analysis, prostate specific antigen density (OR 1.61, P = .010), LDN-PSAD (OR 1.04, P = .012), highest PI-RADS category (3 vs 4, 5; OR 14.5, P < .0001), and location of the lesion with highest PI-RADS category (transition zone vs peripheral zone) (OR 0.34, P = .009) were significant risk factors for detecting clinically significant prostate cancer. Among the patients with the highest PI-RADS category 3 (n=113), clinically significant prostate cancer was detected in 28 patients. On multivariable logistic regression analysis to predict the detection of clinically significant prostate cancer in patients with the highest PI-RADS category 3, age (OR 1.10, P = .026) and LDN-PSAD (OR 1.07, P < .0001) were risk factors for detecting clinically significant prostate cancer. CONCLUSIONS: LDN-PSAD would be a biomarker for detecting clinically significant prostate cancer in patients with prostate specific antigen levels ≤20 ng/mL and suspicious lesions with PI-RADS category ≥3. The use of LDN-PSAD as an adjunct to the use of prostate specific antigen levels would avoid unnecessary biopsies in patients with the highest PI-RADS category 3. Multi-institutional studies with large population are recommended.

Impact of tumor contact surface area on collecting system entry in robot-assisted partial nephrectomy: a retrospective analysis.

BACKGROUND: Collecting system entry in robot-assisted partial nephrectomy may occur even in cases showing a low N factor in the R.E.N.A.L nephrometry score. Therefore, in this study, we focused on the tumor contact surface area with the adjacent renal parenchyma and attempted to construct a novel predictive model for collecting system entry. METHODS: Among 190 patients who underwent robot-assisted partial nephrectomy at our institution from 2015 to 2021, 94 patients with a low N factor (1-2) were analyzed. Contact surface was measured with three-dimensional imaging software and defined as the C factor, classified as C1, < 10 cm [2]; C2, ≥ 10 and < 15 cm [2]; and C3: ≥ 15 cm [2]. Additionally, a modified R factor (mR) was classified as mR1, < 20 mm; mR2, ≥ 20 and < 40 mm; and mR3, ≥ 40 mm. We discussed the factors influencing collecting system entry, including the C factor, and created a novel collecting system entry predictive model. RESULTS: Collecting system entry was observed in 32 patients with a low N factor (34%). The C factor was the only independent predictive factor for collecting system entry in multivariate regression analysis (odds ratio: 4.195, 95% CI: 2.160-8.146, p < 0.0001). Models including the C factor showed better discriminative power than the models without the C factor. CONCLUSIONS: The new predictive model, including the C factor in N1-2 cases, may be beneficial, considering its indication for preoperative ureteral catheter placement in patients undergoing robot-assisted partial nephrectomy.

Preoperative factors affecting the operative outcomes of laparoscopic nephrectomy.

OBJECTIVES: Laparoscopic radical nephrectomy is the standard surgery for localized renal cell carcinoma. Both tumor and patient factors affect the difficulty of laparoscopic radical nephrectomy. Obesity is a major factor influencing technical difficulty in surgical procedures. This study examined preoperative tumor and patient factors affecting the operating time. METHODS: The data of 123 patients who underwent laparoscopic radical nephrectomy at our institution between January 2014 and December 2018 were retrospectively analyzed. The operating time was determined based on the median pneumoperitoneum time. Surgical procedures with a pneumoperitoneum time of ≥130 min were defined as having prolonged pneumoperitoneum time. Multiple logistic regression analyses were performed to identify the preoperative factors affecting the prolonged pneumoperitoneum time, and risk stratification was performed based on these factors. RESULTS: Multiple logistic regression analyses revealed that a total number of renal pedicle blood vessels ≥3 and a visceral fat volume ≥3000 cm3 were associated with prolonged pneumoperitoneum time of laparoscopic radical nephrectomy. Based on the multivariate analysis results, these factors were considered individually, and the cohort was stratified into three risk groups: low (0 point), intermediate (1 point), and high (2 points) risk groups. The pneumoperitoneum time was significantly prolonged as the number of risk factors increased. CONCLUSIONS: We developed a risk stratification model using preoperative factors to predict the prolonged pneumoperitoneum time of laparoscopic radical nephrectomy, which can help select suitable cases that are appropriate for each surgeon's skill level.

How long should urologists observe patients with prostate cancer after radical prostatectomy? Weibull analysis.

OBJECTIVES: There is no recommended observation time for patients who have undergone radical prostatectomy for prostate cancer. This study was undertaken to determine the postoperative observation time by investigating the hazard rate for prostate-specific antigen failure and other-cause death using Weibull analysis. METHODS: We included 612 patients who underwent laparoscopic radical prostatectomy for localized prostate cancer between June 2002 and December 2017. Risk classification was categorized by the D'Amico risk classification, and the patients were divided into three age groups: <60, 60-69 and ≥70 years. The hazard rates at each point were derived using Weibull analysis. The optimal observation time after laparoscopic radical prostatectomy was determined as the intersection point at which the hazard rate of other-cause death overtakes the hazard rate of prostate-specific antigen failure. RESULTS: In all groups classified by age, the hazard rate of other-cause deaths increased over time. In contrast, the hazard rate of prostate-specific antigen failure decreased gradually. The ≥70 years age group showed the highest hazard rate. The hazard rate of prostate-specific antigen failure was highest in the high-risk group. The patients aged ≥70 and 60-69 years in the low-risk group were recommended 6 years 6 months and 14 years 8 months, respectively, for observation. The remaining patients were recommended >25 years of postsurgical observation. CONCLUSIONS: The observation time after laparoscopic radical prostatectomy could be estimated by comparing the estimated hazard rates of prostate-specific antigen failure and other-cause death based on Weibull analysis. Urologists should pay attention to age and risk classifications for optimal postoperative observation.

Conditional Survival and Time of Biochemical Recurrence of Localized Prostate Cancer in Japanese Patients Undergoing Laparoscopic Radical Prostatectomies.

PURPOSE: Using conditional survival (CS) analysis, we investigated whether the duration of survival without biochemical recurrence (BCR) of prostate cancer after laparoscopic radical prostatectomies (LRP) affected the BCR rate. We also investigated the impact of well-known risk factors for BCR. METHODS: Between 2002 and 2014, 627 consecutive patients underwent LRPs at our institution. Prostate-specific antigen (PSA) concentrations above 0.2  ng/mL were defined as BCR. Conditional BCR-free survival rates were determined through Kaplan-Meier analysis. Assessment of potential BCR risk factors was performed using a Cox proportional hazard analysis. RESULTS: The 10-year BCR-free rates after LRP increased to 82.4%, 84.5%, 86.6%, 90.1%, and 94.7% in patients surviving 1, 2, 3, 5, and 7.5 years without BCR, respectively. Multivariate analyses of age, PSA concentrations, neoadjuvant therapy, and pathological findings were performed for all patients. In all patients, positive surgical margins (PSM) and Gleason Grade Groups (GG) ≥ 4 were independent risk factors for BCR (p < 0.001, hazard ratio [HR] = 2.45; and p < 0.001, HR = 2.83, respectively,). Similarly, PSM and GG ≥ 4 were significant risk factors in patients surviving 1-5 years without BCR. No clear risk factors were observed in patients surviving > 5 years without BCR after LRPs. CONCLUSIONS: The BCR-free rate increased with time after LRP. It is recommended that patients with PSM, GG ≥ 4, or with both factors are strictly monitored for 5 years postoperatively. CS analysis is particularly useful for predicting the postoperative course of patients.

Effects of psoas major muscle volume in predicting the prognosis of patients with upper urinary tract urothelial carcinoma treated with radical nephroureterectomy.

BACKGROUND: This study evaluated the impact of sarcopenia and psoas major muscle volume on the survival of patients with upper urinary tract urothelial carcinoma who had undergone radical nephroureterectomy. METHODS: We reviewed data from 110 patients treated with radical nephroureterectomy in our department between June 2007 and February 2017. Psoas major muscle volume was quantified based on computed tomography data using Synapse Vincent software. The psoas major muscle volume index was calculated as psoas major muscle volume/height squared (cm3/m2). We analysed relapse-free survival, cancer-specific survival and overall survival after radical nephroureterectomy to identify factors that predicted patient survival. RESULTS: The median psoas major muscle volume index was 121.5 cm3/m2, and the psoas major muscle volume index was <100 cm3/m2 in 34 of 110 patients (30.9%). Multivariate analysis indicated that ≥pT3-stage cancer, lymphovascular invasion and a psoas major muscle volume index of <100 cm3/m2 were independent predictors of shorter relapse-free survival, cancer-specific survival and overall survival. Using these factors, patients were stratified into three groups: low, intermediate and high risks for relapse-free survival, cancer-specific survival and overall survival. CONCLUSIONS: Low psoas major muscle volume resulting from sarcopenia, high T stage and the presence of lymphovascular invasion was associated with poor survival in patients with urinary tract urothelial carcinoma who had undergone radical nephroureterectomy, supporting the use of psoas major muscle volume as a new objective prognostic marker.

What factors affect the operative time of robot-assisted laparoscopic radical prostatectomy?

BACKGROUND: Robot-assisted radical prostatectomy (RARP) has gained prominence since the da Vinci surgical system was introduced in 2000. RARP has now become a standard procedure for treating cases with localized prostate cancer. However, no study has examined its surgical time by accurately measuring the pelvic visceral fat (PVF) volume. This study aimed to investigate the factors associated with prolonged console time and surgical difficulty by RARP surgeons. METHODS: This study included 405 patients who underwent RARP between 2014 and 2019 at our institution. Given that the anatomical characteristics were considered to affect RARP, PVF and working space (WS) were estimated preoperatively by computed tomography using a 3D image analysis system. Univariate and multivariate logistic regression analyses were performed to identify the factors prolonging console time, such as body mass index (BMI), prostate volume, previous abdominal surgery, nerve-sparing procedure, PVF, and WS. We also investigated whether post-operative complications were associated with any of these factors. RESULTS: Larger PVF (p = 0.028, odds ratio (OR) 1.43), smaller WS (p < 0.001, OR 2.48), and the nerve-sparing procedure (p = 0.037, OR 1.61) were statistically significant factors associated with prolonged console time. Furthermore, higher BMI (p = 0.013, OR 1.49) and smaller pelvic width (p < 0.001, OR 2.63) were the alternative and more practical factors associated with prolonged console time. The post-operative anastomotic leakage occurrence rate increased with the number of risk factors, while post-operative complications did not change even in high-risk cases. CONCLUSION: PVF and WS are significant factors associated with prolonged console time in RARP cases. However, BMI can be as useful as PVF, since BMI significantly correlated with PVF. Additionally, pelvic width (PW) can be an alternative to WS, since PW correlated with WS. This study demonstrated that preoperative BMI and PW might predict the surgical risk and identify suitable RARP cases for novice surgeons.

Clinical impact of psoas muscle volume on the development of inguinal hernia after robot-assisted radical prostatectomy.

BACKGROUND: Sarcopenia, a syndrome characterized by the loss of skeletal muscle mass, has attracted attention in the field of oncology, as it reflects poor nutritional status. The present study aimed to determine the risk factors for postoperative inguinal hernia (PIH) development after robot-assisted laparoscopic radical prostatectomy (RARP) for prostate cancer, and discuss whether sarcopenia could be used as a sensitive predictor of PIH. METHODS: We reviewed the medical records of 147 patients who underwent RARP at our institution. The psoas muscle volume (PMV), as an indicator of sarcopenia, was quantified from computed tomography images using a 3-dimensional image analysis system. Multivariate cox regression analyses were performed to identify independent predictors of PIH, including pre- and peri-operative factors. RESULTS: The mean PMV was 393 cm3, and the correlation coefficient between PMV and body mass index was 0.37 (p < 0.01). The PIH-free rate at 2 years postoperatively was 78.2% among all patients. The multivariate analysis revealed that a PMV < 350 cm3 was a significant risk factor for PIH (p = 0.03; hazard ratio 2.19). Body mass index, age, prostate volume, lymph node dissection, nerve sparing, rectus muscle thickness, and console time were not related to PIH development. The PIH-free rate at 2 years postoperatively was 83.4% and 68.9% in patients with a PMV ≥ 350 cm3 and < 350 cm3, respectively (p < 0.05). CONCLUSIONS: PIH occurred significantly more frequently in patients with a PMV < 350 cm3 than in patients with a PMV ≥ 350 cm3, and a low PMV was an independent risk factor for PIH. Thus, urologists should pay attention to the cumulative incidence of IH after RARP, especially in patients with a PMV < 350 cm3.

Analysis of oncological outcomes of whole-gland therapy with high-intensity focused ultrasound for localized prostate cancer in clinical and technical aspects: a retrospective consecutive case-series analysis with a median 5-year follow-up.

PURPOSE: This study aimed to analyze technical and clinical factors related to oncological outcomes in patients with localized prostate cancer (PC) who were treated with whole-gland high-intensity focused ultrasound (HIFU). MATERIALS AND METHODS: From 2007-2014, patients diagnosed with localized PC who underwent whole-gland HIFU were consecutively included retrospectively. Biochemical failure was defined according to the Phoenix ASTRO guidelines. The relationship between oncological outcomes and technical and clinical factors was evaluated. RESULTS: The study cohort included 428 patients. The median age was 67 years, and the median prostate-specific antigen level was 7.61 ng/mL. Patient risk classifications were low (n = 102), intermediate (n = 240), and high (n = 86). Biochemical disease-free survival rates of patients with HIFU for localized PC in the total, low-, intermediate-, and high-risk groups according to D'Amico risk groups over a median follow-up period of 5 years (range 9-144) were 68.4%, 80.4%, 65.6%, and 61.6%, respectively. In multivariate logistic regression analyses to predict biochemical failure of the treatment, neoadjuvant hormonal therapy (NHT) in the high-risk group (OR 0.225, p = 0.015), and compression method in the low- (OR 0.178, p = 0.030), intermediate- (OR0.291, p < 0.0001), and high-risk (OR 0.316, p = 0.049) groups were significant factors that reduced the risk of biochemical failure after treatment. There were no significant differences in complications between patients treated with compression and those treated conventionally. CONCLUSIONS: NHT may potentially improve oncological outcomes for patients in the high-risk group, and compression methods can improve the oncological outcomes of whole-gland therapy with HIFU.

Functional outcomes of transurethral thulium laser enucleation versus bipolar transurethral resection for benign prostatic hyperplasia over a period of 12 months: A prospective randomized study.

OBJECTIVE: To evaluate functional outcomes over a year for benign prostatic hyperplasia treated with thulium laser enucleation of the prostate or bipolar transurethral resection of the prostate. METHODS: In this study, we prospectively included 140 patients who were treated for benign prostatic hyperplasia from April 2017 to February 2019. A randomization list was used for non-blind assignment to treatment groups (thulium laser enucleation of the prostate or bipolar transurethral resection of the prostate). The International Prostate Symptom Score, International Prostate Symptom Score quality of life, Overactive Bladder Symptom Score, uroflowmetry and International Index of Erectile Function-5 were used for the assessment of outcomes. Scores were taken before treatment, and at 1, 3, 6, 9 and 12 months after treatment. RESULTS: Preoperatively, characteristics of patients in the thulium laser enucleation of the prostate group (n = 70) and the bipolar transurethral resection of the prostate group (n = 70) did not significantly differ. The thulium laser enucleation of the prostate group had a lower median decrease in hemoglobin (0.10 g/dL vs 0.69 g/dL, P < 0.0001) and shorter median catheterization (2 days vs 3 days, P < 0.0001) than the bipolar transurethral resection of the prostate group. Both groups had significantly improved International Prostate Symptom Score, International Prostate Symptom Score quality of life, Overactive Bladder Symptom Score, maximum flow rate and residual urine compared with preoperative values. In the thulium laser enucleation of the prostate group, erectile function was significantly impaired at 1 month post-treatment compared with pretreatment, but improved to baseline at 3 months; however, the transurethral resection of the prostate group did not recover. However, total energy (P = 0.001) and laser irradiation time (P = 0.025) were significantly different between the patients who had preserved erectile function and those who did not after the treatment in the thulium laser enucleation of the prostate group. CONCLUSIONS: Thulium laser enucleation of the prostate is superior to bipolar transurethral resection of the prostate in resection efficacy, hemostasis, catheterization time and preservation of erectile function. However, excessive laser irradiation time in thulium laser enucleation of the prostate has the possibility to delay improvement of overactive bladder symptoms and decrease sexual function.

Accuracy of real-time magnetic resonance imaging-transrectal ultrasound fusion image-guided transperineal target biopsy with needle tracking with a mechanical position-encoded stepper in detecting significant prostate cancer in biopsy-naïve men.

OBJECTIVE: To evaluate the accuracy of real-time elastic fusion image-guided transperineal prostate biopsy with needle tracking involving a mechanical position-encoded stepper in detecting clinically significant prostate cancer for biopsy-naïve men. METHODS: We prospectively recruited patients with serum prostate-specific antigen levels of 4.0-20 ng/mL and suspicious of prostate cancer on multiparametric magnetic resonance imaging. They underwent targeted biopsies for cancer-suspicious lesions and 12-core systematic biopsies. Pathological findings from biopsy cores and whole-mount specimens (for those who underwent radical prostatectomy) were analyzed. RESULTS: A total of 250 patients were included, in whom targeted and systematic biopsies detected significant cancers in 55% and 25%, respectively (P < 0.001). The targeted biopsy cores (n = 527) showed significantly greater biopsy-proven significant cancer detection rates (P < 0.001), cancer core length (P < 0.0001), cancer core percentage (P < 0.001) and Gleason scores (P < 0.001) than did the systematic biopsies. The significant cancer detection rate for targeted lesions (those with Prostate Imaging and Reporting and Data System classification scores of 5) was 80%. Biopsy-proven significant cancer detection rates for targeted lesions ≤10 mm and >10 mm were similar for Prostate Imaging and Reporting and Data System scores of 4 (P = 0.707) and 5 (P = 0.386). In whole-mount specimens (n = 30), locations for 95% of significant cancers were diagnosed preoperatively. Targeted biopsies alone diagnosed 79% of significant cancers. CONCLUSIONS: Although targeted biopsies are superior to systematic biopsies in detecting significant cancers, systematic biopsies maintain an important role in the diagnosis of prostate cancer in biopsy-naïve men.

Surgical Orthodontic Treatment for Open Bite in Noonan Syndrome Patient: A Case Report.

Noonan syndrome, characterized by short stature, facial anomalies, and congenital heart defects, may also be associated with hematopoietic disorders. Craniofacial anomalies in affected patients include hypertelorism and severe open bite associated with masticatory dysfunction. We treated a Noonan syndrome patient with a skeletal open bite. Surgical orthodontic treatment including two-jaw surgery established a good occlusal relationship after correction of severe anemia. Both upper and lower incisors were moved to upright positions, while clockwise rotation of the palatal plane and decreased mandibular plane angle were accomplished. Lower masticatory activity may affect posttreatment occlusion in such cases.

Biomechanical analysis of poly-L-lactic acid and titanium plates fixated for mandibular symphyseal fracture with a conservatively treated unilateral condylar fracture using the three-dimensional finite element method.

The purpose of this study was to investigate stress on poly-L-lactic acid (PLLA) plates with a thickness of 1.4 mm and titanium plates with a thickness of 1.0 and 1.4 mm placed for mandibular symphyseal fractures with or without conservatively treated, unilateral condylar fractures using finite element analysis. The symphyseal fracture region was defined by the following three conditions: the defect, the callus, and the contact condition. Stress on the plates was analyzed by an applying occlusal force of 478.1 N on the first molar of the non-condylar fracture side. In the model of isolated symphyseal fracture, the maximal stresses were below the material strength in all plate types and conditions. In the models with condylar fracture, the maximal stresses on these plates were much higher than those in the models of isolated symphyseal fracture, especially for the defect condition. Although the maximal stresses on all types of plates in the contact condition were below the material strengths, some of those in the defect condition were higher than these strengths. These results suggest that a PLLA plate can theoretically withstand stress under good reductions of symphyseal fractures, even for condylar fractures; however, both the PLLA plate and titanium miniplate may be at risk of fracture under poor reduction.

Influence of bone parameters on peri-implant bone strain distribution in the posterior mandible.

OBJECTIVES: The success rate of dental implants depends on the type of bone at the implant site. The purpose of the present study was to investigate the effects of the bone parameters at the implant-placement site on peri-implant bone strain distributions. STUDY DESIGN: The morphologies and bone densities of seventy-five potential implant sites in the posterior mandible were measured using computed tomography (CT). Based on the CT data, we defined bone parameters (low and high in terms of cancellous-bone density and crestal-cortical bone density, and thin and thick in terms of crestal-cortical bone thickness), and we constructed finite-element models simulating the various bone types. A buccolingual oblique load of 200 N was applied to the top of the abutment. The von Mises equivalent (EQV) strains in the crestal-cortical bone and in the cancellous bone around the implant were calculated. RESULTS: Cancellous-bone density greatly affected the maximum EQV strain regardless of the density and thickness of the crestal cortical-bone. The maximum EQV strains in the crestal cortical-bone and the cancellous bone in the low-density cancellous-bone models (of 150 Hounsfield units (HU)) were 1.56 to 2.62-fold and 3.49 to 5.31-fold higher than those in the high-density cancellous-bone models (of 850 HU), respectively. The crestal cortical-bone density affected the maximum EQV strains in the crestal cortical-bone and in the cancellous bone in the low-density cancellous-bone models. The crestal cortical-bone thickness affected the maximum EQV strains in the cancellous bone and in the crestal cortical-bone in the low-density cancellous-bone models. CONCLUSIONS: Our results confirm the importance of bone types for the peri-implant bone strain distribution. Cancellous-bone density may be a critical factor for peri-implant bone strain.

Total pelvic floor reconstruction during non-nerve-sparing laparoscopic radical prostatectomy: impact on early recovery of urinary continence.

OBJECTIVES: To develop a modified technique of "total pelvic floor reconstruction" during non-nerve-sparing laparoscopic radical prostatectomy, and to determine its effect on postoperative urinary outcomes. METHODS: A total of 128 patients who underwent non-nerve-sparing laparoscopic radical prostatectomy were evaluated, including 81 with total pelvic floor reconstruction and 47 with non-total pelvic floor reconstruction. Nerve-sparing cases were excluded. Urinary outcomes were assessed with self-administrated questionnaires (Expanded Prostate Cancer Index Composite) at 1, 3, 6 and 12 months after laparoscopic radical prostatectomy. The total pelvic floor reconstruction technique included two concepts involving posterior and anterior reconstructions. In posterior reconstruction, Denonvilliers' fascia was approximated to the bladder neck and the median dorsal raphe by slipknot. The anterior surface of the bladder-neck was approximated to the anterior detrusor apron and the puboprostatic ligament collar for anterior reconstruction. RESULTS: There were no significant differences between the two groups in the patients' characteristics, and in perioperative and oncological outcomes. In the total pelvic floor reconstruction group, the continence rates at 3, 6 and 12 months after laparoscopic radical prostatectomy were 45.7%, 71.4%, and 84.6%, respectively. In the non-total pelvic floor reconstruction group, the continence rates were 26.1%, 46.8% and 60.9%, respectively. The total pelvic floor reconstruction technique resulted in significantly higher continence rates at 3, 6 and 12 months after laparoscopic radical prostatectomy, respectively (all P < 0.05). The mean interval to achieve continence was significantly shorter in the total pelvic floor reconstruction group (mean 7.7 months) than in the non-total pelvic floor reconstruction group (mean 9.8 months; P = 0.0003). CONCLUSION: The total pelvic floor reconstruction technique allows preservation of the blood supply to the urethra and physical reinforcement of the pelvic floor. Therefore, this technique is likely to improve urinary continence outcomes after laparoscopic radical prostatectomy.

Dorsal vein complex preserving technique for intrafascial nerve-sparing laparoscopic radical prostatectomy.

OBJECTIVES: To describe a novel dorsal vein complex preserving technique for intrafascial nerve-sparing laparoscopic radical prostatectomy and to evaluate its postoperative outcomes. METHODS: A total of 109 patients who underwent laparoscopic radical prostatectomy by a single surgeon were evaluated, including 44 patients with dorsal vein complex preserving technique for intrafascial nerve-sparing laparoscopic radical prostatectomy, 20 patients with conventional intrafascial nerve-sparing laparoscopic radical prostatectomy and 45 patients with non-nerve-sparing laparoscopic radical prostatectomy. Functional outcomes were evaluated using a self-administered questionnaire (Expanded Prostate Cancer Index Composite). Continence was defined as zero to one security pad per day. Oncological outcomes were evaluated based on positive surgical margin. RESULTS: In the dorsal vein complex preserving technique for intrafascial nerve-sparing laparoscopic radical prostatectomy group, the continence rate was 57%, 77% and 95% at 1, 3 and 12 months, respectively. The continence rate in the conventional intrafascial nerve-sparing laparoscopic radical prostatectomy group was 37%, 63% and 90%, and in the non-nerve-sparing laparoscopic radical prostatectomy group it was 23%, 57% and 82% at 1, 3, and 12 months, respectively. The dorsal vein complex preserving technique for intrafascial nerve-sparing laparoscopic radical prostatectomy group showed a significantly earlier recovery from incontinence compared with that in the conventional intrafascial nerve-sparing laparoscopic radical prostatectomy and non-nerve-sparing laparoscopic radical prostatectomy groups (log-rank test, P = 0.044 and P < 0.001). Similarly, the dorsal vein complex preserving technique for intrafascial nerve-sparing laparoscopic radical prostatectomy group tended to show a more early recovery in relation to urinary function of the Expanded Prostate Cancer Index Composite. Regarding sexual function, there were no significant differences between the dorsal vein complex preserving technique for intrafascial nerve-sparing laparoscopic radical prostatectomy and conventional intrafascial nerve-sparing laparoscopic radical prostatectomy groups. In pT2 patients, the positive surgical margin rate of the dorsal vein complex preserving technique for intrafascial nerve-sparing laparoscopic radical prostatectomy group (11%) was similar to that of the other two groups (conventional intrafascial nerve-sparing laparoscopic radical prostatectomy 7%; non-nerve-sparing laparoscopic radical prostatectomy 11%). CONCLUSIONS: The dorsal vein complex preserving technique for intrafascial nerve-sparing laparoscopic radical prostatectomy technique provides early recovery from incontinence without adversely affecting the oncological outcome.

Effect of clenching on biomechanical response of human mandible and temporomandibular joint to traumatic force analyzed by finite element method.

PURPOSE: The purpose of the present study was to analyze the effect of clenching on the biomechanical response of human mandible and temporomandibular joint (TMJ) to traumatic force by the finite element (FE) method. MATERIAL AND METHODS: FE models of the mandible and the TMJ in resting and clenching positions were prepared. Distribution and magnitude of von Mises stress were analyzed by applying force as a point load in the symphyseal, canine, body and angle regions of the mandible. In addition, strain energy density (SED) at the articular disc and in posterior connective tissue of TMJ was analyzed. RESULTS: In the resting position, von Mises stress was mainly concentrated at the condylar neck and in the retromolar region of the mandible. In the clenching position, the stress at the condylar neck decreased in all loadings. The stress in the retromolar region similary decreased in the symphyseal, canine and body loading, respectively; however, higher stress was observed in the retromolar region on the loading side in the angle loading. High SED was generated at the articular disc and in posterior connective tissues of TMJ in the resting position. The SED in these tissues decreased in all loadings in the clenching position. CONCLUSIONS: Clenching generally reduces stress at the condylar neck and in the retromolar region of the mandible, and strain energy at the articular disc and in posterior connective tissue of TMJ by traumatic forces on the mandible; however, clenching induces greater stress in the retromolar region on the loading side by traumatic force to the angle region.

Changes in strain energy density in the temporomandibular joint disk after sagittal split ramus osteotomy using a computed tomography-based finite element model.

PURPOSE: We evaluated the changes in the strain energy density (SED) in the temporomandibular joint (TMJ) disk after sagittal split ramus osteotomy (SSRO) at three time points. A finite element model (FEM) based on real patient-based computed tomography (CT) data was used to examine the effect of SSRO on the TMJ. METHODS: Measurements of the condylar position and angulation in CT images and FEM analyses were performed for 17 patients scheduled to undergo SSROs at the following time points: before surgery, immediately after surgery, and 1 year after surgery. SED on the entire disk was calculated at each of the three time points using FEM. Furthermore, the relationship between individual SED values and the corresponding condylar position was also evaluated. RESULTS: No significant change was observed in the condylar position at the three time points. The FEM analysis showed that SED was the highest and lowest immediately after and 1 year after surgery, respectively. A possible SED distribution imbalance between the left and right joints was improved 1 year after SSRO. Concerning the effect of fossa morphometry and condylar position, wide and deep glenoid fossae and a more posterior condylar position tended to show lower SED. CONCLUSION: SED in the articular disk temporarily increased after surgery and significantly decreased 1 year after surgery compared with that before surgery. SSRO generally improved the imbalance between the left and right joints. Thus, SSRO, which improves maxillofacial morphology, may also improve components of temporomandibular disorders.

Impact of stone volume on treatment outcomes of percutaneous nephrolithotripsy.

PURPOSE: We aimed to evaluate the impact of stone volume on the surgical outcomes of patients who underwent percutaneous nephrolithotripsy, which is the preferred treatment for renal and upper ureteral stones. MATERIALS AND METHODS: This retrospective study included 37 patients who underwent percutaneous lithotripsy between 2013 and 2019. Preoperative and postoperative stone volumes were quantified using computed tomography scan data. RESULTS: The mean preoperative and postoperative stone volumes were 10.7 cm3 (1.1-50.2 cm3 ) and 2.1 cm3 (0-18.2 cm3 ), respectively. The correlation coefficient between the stone volume and maximum stone length was 0.62 (P < .01). A residual stone volume of >5 mm was observed in 17 cases (45.9%). Thirteen cases underwent secondary treatment (35.1%) who had a preoperative stone volume of >15 cm3 or a postoperative stone volume of <2 cm3 . The areas under the curve for the stone volume for treatment success and the requirement for secondary treatment were 0.701 and 0.739, respectively, and were higher than those of stone length (0.638 and 0.558) and shape (0.644 and 0.641). CONCLUSIONS: Measurement of stone volume using three-dimensional imaging is simple and greatly impacted the course of stone treatment. Information on stone volume may predict an increased likelihood of secondary treatment in patients with a preoperative stone volume of >15 cm3 .