Nasal Osteotomies Revisited in Asians: Surface Aesthetics, Anatomical and Technical Considerations.

Background Although osteotomy is commonly performed in rhinoplasty, it is difficult for less experienced surgeon to understand mechanism of the procedure. The primary goal of this study is to improve understanding of nasal osteotomy in Asians by considering the surface aesthetics and anatomy of the nose as well as their relationships with the surgical procedure. Methods Surface aesthetics, anatomic considerations, kinetics of medial and lateral osteotomy, fracture levels of osteotomy were discussed in detail by reviewing the previous publications and 18 years of our experience. Moreover, the technical details of osteotomy were explained and personal tips for performing successful osteotomy were described. Results Dorsal and lateral aesthetic lines, dorsal and basal widths are main characteristics related to the surface aesthetics of nose to perform the osteotomy. In addition, these features are different in Asian population due to the anatomic difference with Caucasians, which makes the procedure difficult and requires more attention to perform osteotomy. Conclusion Because osteotomy is one of the most traumatic and invasive part of the rhinoplasty, it is crucial for the rhinoplasty surgeon to understand the relationship between surface aesthetics and osteotomy techniques to produce consistent and reproducible results.

Training ultrasound-guided percutaneous nephrostomy technique with porcine model.

PURPOSE: There is increasing interest in the use of ultrasound for endoscopic and percutaneous procedures. Access can be achieved without radiation exposure under ultrasound guidance. Our aim was to develop a porcine-based training model for ultrasound-guided percutaneous renal access that could also be personalized to a specific patient. MATERIALS AND METHODS: The Institutional Animal Care and Use Committee of Severance Hospital approved the study protocol. An anesthetized pig was placed in the dorsal lithotomy position. For the nephrostomy puncture, a Chiba biopsy needle with an echo tip was used under ultrasound guidance. Eight residents and three consultants in urology participated. Puncture time was defined as the nephrostomy time to confirm the flow of irrigation via the needle. After training, satisfaction survey results for clinical usability and procedural difficulty were evaluated. RESULTS: The 5-point Likert scale satisfaction survey for clinical usability and procedural difficulty found mean results of 4.64 and 4.09 points, respectively. There were no differences between residents and consultants for either variable. For all participants combined, there was a significant difference for nephrostomy time between the first and second trials (278.8±70.6 s vs. 244.5±47.0 s; p=0.007). The between-trial difference was greater for residents (291.5±71.2 s vs. 259.1±41.9 s; p=0.039). The difference for the consultant was not significant (245.0±69.4 s vs. 205.7±42.5 s; p=0.250). CONCLUSIONS: We developed a porcine-based ultrasound-guided nephrostomy puncture training model. Satisfaction survey results indicated high clinical usability and procedural difficulty. For nephrostomy time, the model was more effective for urology residents than for consultants.

Clinical Course and Mutational Analysis of Patients with Cystine Stone: A Single-Center Experience.

Cystinuria is a known genetic disorder. To date, two genes, SLC3A1 and SLC7A9, have been identified as causes of cystinuria. In this study of 10 patients with cystinuria, which is the largest Korean cohort ever studied, we examined the patients' phenotypes, clinical courses, and genetic analyses. A total of 10 patients with cystinuria diagnosed with cystine stones in a single tertiary medical center (Severance Hospital, Seoul, Republic of Korea) from April 2000 to July 2023 were included in the study. All of the patients participated in mutational studies, and the clinical presentation and consecutive laboratory findings of the patients were analyzed retrospectively. After the initial stone-related surgery or procedure at our hospital, 6 of the 10 patients underwent additional surgery at least once for recurrent stones. Genetic analyses identified six new mutations, of which only two patients had type B mutations. The most common genotype was compound heterozygous type A. We investigated the genotypes and clinical courses of 10 Korean patients with cystinuria who had not been previously reported. More data are needed to statistically analyze the genotype and phenotype of cystinuria.

Impact of Preoperative Ureteral Stenting in Retrograde Intrarenal Surgery for Urolithiasis.

Background and Objectives: Ureteral stent insertion passively dilates the ureter. Therefore, it is sometimes used preoperatively before flexible ureterorenoscopy to make the ureter more accessible and facilitate urolithiasis passage, especially when ureteroscopic access has failed or when the ureter is expected to be tight. However, it may cause stent-related discomfort and complications. This study aimed to assess the effect of ureteral stenting prior to retrograde intrarenal surgery (RIRS). Materials and Methods: Data from patients who underwent unilateral RIRS for renal stone with the use of a ureteral access sheath from January 2016 to May 2019 were retrospectively analyzed. Patient characteristics, including age, sex, BMI, presence of hydronephrosis, and treated side, were recorded. Stone characteristics in terms of maximal stone length, modified Seoul National University Renal Stone Complexity score, and stone composition were evaluated. Surgical outcomes, including operative time, complication rate, and stone-free rate, were compared between two groups divided by whether preoperative stenting was performed. Results: Of the 260 patients enrolled in this study, 106 patients had no preoperative stenting (stentless group), and 154 patients had stenting (stenting group). Patient characteristics except for the presence of hydronephrosis and stone composition were not statistically different between the two groups. In surgical outcomes, the stone-free rate was not statistically different between the two groups (p = 0.901); however, the operation time for the stenting group was longer than that of the stentless group (44.8 ± 24.2 vs. 36.1 ± 17.6 min; p = 0.001). There were no differences in the complication rate between the two groups (p = 0.523). Conclusions: Among surgical outcomes for RIRS with a ureteral access sheath, preoperative ureteral stenting does not provide a significant advantage over non-stenting with respect to the stone-free rate and complication rate.

Surgical anatomy for Asian rhinoplasty: Part III.

This article, which comprises the third part of a series on surgical anatomy for Asian rhinoplasty, addresses the lower one-third of the nose, including the alar cartilage and tip-supporting structures, known as distal mobile framework. As discussed in earlier parts of this series, diversity in surgical anatomy results in different surgical techniques in Asian rhinoplasty compared to rhinoplasty in Caucasian patients. Nasal tip structures are especially important due to their crucial importance for changing the nasal shape in Asians. This article, along with the previous ones, will provide both basic and advanced knowledge of practical surgical anatomy for Asian rhinoplasty.

A New Parameter for Calcium Oxalate Stones: Impact of Linear Calculus Density on Non-Contrast Computed Tomography.

Background and Objectives: Non-contrast computed tomography (NCCT) is widely used to evaluate urolithiasis. The NCCT attenuation, measured in Hounsfield units (HU), has been evaluated to predict stone characteristics. We propose a novel parameter, linear calculus density (LCD), and analyze variables from NCCT imaging to predict calcium oxalate (CaOx) stones, which are common and challenging to fragment. Materials and Methods: We retrospectively reviewed the medical records of patients with urolithiasis between 2014 and 2017. Among those, 790 patients were included. Based on the NCCT pre-treatment, the maximal stone length (MSL), mean stone density (MSD), and stone heterogeneity index (SHI) were obtained. In addition, the variation coefficient of stone density (VCSD = SHI/MSD × 100) and linear calculus density (LCD = VCSD/MSL) were calculated. In accordance with the stone analysis, the patients were divided into two groups (CaOx and non-CaOx groups). The logistic regression model and receiver operating characteristic (ROC) curve were used for predictive modeling. Results: In the CaOx group, the SHI, VCSD, and LCD were more significant than in the non-CaOx group (all p < 0.001). SHI (OR 1.002, 95% CI 1.001-1.004, p < 0.001), VCSD (OR 1.028, 95% CI 1.016-1.041, p < 0.001), and LCD (OR 1.352, 95% CI 1.270-1.444, p < 0.001) were significant independent factors for CaOx stones in the logistic regression models. The areas under the ROC curve for predicting CaOx stones were 0.586 for SHI, 0.66 for VCSD, and 0.739 for LCD, with a cut-point of 2.25. Conclusions: LCD can be a useful new parameter to provide additional information to help discriminate CaOx stones before treatment.

Silodosin versus Tamsulosin for Medical Expulsive Therapy of Ureteral Stones: An Updated Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Background and Objectives: This systematic review and meta-analysis of randomized controlled trials was performed to compare the therapeutic effects and safety profiles of silodosin and tamsulosin for medical expulsive therapy (MET) of ureteral stones. Materials and Methods: We searched PubMed, EMBASE, the Cochrane Library, and Web of Science to identify articles published before July 2022 that described randomized controlled trials comparing silodosin and tamsulosin for MET of ureteral stones. Endpoints were stone expulsion rate, stone expulsion time, and total complication rate. Results: In total, 14 studies were included in our analysis. The size of ureteral stones was <1 cm. Compared with tamsulosin, silodosin resulted in a significantly higher stone expulsion rate (p < 0.01, odds ratio (OR) = 2.42, 95% confidence interval (CI) = 1.91 to 3.06, I2 = 0%) and significantly shorter stone expulsion time (p < 0.01, mean difference = −3.04, 95% CI = −4.46 to −1.63, I2 = 89%). The total complication rate did not significantly differ between silodosin and tamsulosin (p = 0.33, OR = 1.15, 95% CI = 0.87 to 1.52, I2 = 7%). Conclusions: Compared with tamsulosin, silodosin resulted in significantly better expulsion of ureteral stones <1 cm. The total complication rate did not significantly differ between silodosin and tamsulosin. Thus, silodosin may be superior to tamsulosin for MET of ureter stones <1 cm.

Surveillance versus Adjuvant Treatment with Chemotherapy or Radiotherapy for Stage I Seminoma: A Systematic Review and Meta-Analysis According to EAU COVID-19 Recommendations.

Background and Objectives: During the coronavirus disease 2019 (COVID-19) outbreak, the European Association of Urology (EAU) Guidelines Office Rapid Reaction Group (GORRG) recommended that patients with clinical stage I (CSI) seminoma be offered active surveillance (AS). This meta-analysis aimed to evaluate the efficacy of AS versus adjuvant treatment with chemotherapy or radiotherapy for improving the overall survival (OS) of CSI seminoma patients. Materials and Methods: A systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The PubMed/Medline, EMBASE, and Cochrane Library databases were searched. The primary outcome was 5-year OS, and the secondary outcome was the 5-year relapse-free survival (RFS). The outcomes were analyzed as odds ratios (ORs) and 95% confidence intervals (CIs). Results: A total of 14 studies were included. Overall, the quality scores were relatively high, and little publication bias was noted. In terms of the 5-year OS, 7 studies were analyzed; there was no significant difference between AS and adjuvant treatment (OR, 0.99; 95% CI, 0.41−2.39; p = 0.97). In terms of 5-year RFS, 12 studies were analyzed. Adjuvant treatment reduced the risk of 5-year recurrence by 85% compared with AS (OR, 0.15; 95% CI, 0.08−0.26; p < 0.001). Conclusions: In terms of the OS in CSI seminoma patients, no intergroup difference was noted, so it is reasonable to offer AS, as recommended by the EAU GORRG until the end of the COVID-19 pandemic. However, since there is a large intergroup difference in the recurrence rate, further research on the long-term (>5 years) outcomes is warranted.

Comparison of Surgical Outcomes between Single-Use and Reusable Flexible Ureteroscopes for Renal Stone Management: A Systematic Review and Meta-Analysis.

Background and Objectives: Disposable flexible ureteroscopes have been widely used because of their cost-effectiveness and higher sterility potential compared with reusable flexible ureteroscopes. This study aimed to compare the surgical outcomes and complication rates in patients who undergo reusable or disposable flexible ureteroscopic stone surgeries (fURS) for urinary stone disease. Materials and Methods: A systematic review and meta-analysis were conducted under the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. This systematic review was registered with PROSPERO (CRD42022331291). Clinical trials comparing reusable and disposable fURS for stone disease were found from PubMed, EMBASE, Cochrane Library, and the Web of Science up to March 2022. Participants were patients with upper urinary tract stones; the interventions were reusable or disposable fURS. Outcomes, including stone-free rate, operation time, length of hospital stay, and complication rate, were compared for analysis. Results: Overall, 111 studies were identified, but after removing duplicate studies, 75 studies remained. Thirty-two of these studies were excluded. Of the 43 screened studies, 11 met the eligibility criteria. There was no difference in the stone-free rate (SFR) between disposable and reusable fURS (p = 0.14; OR = 1.36; 95% CI, 0.9 to 2.04). For operation time, no difference was identified between reusable and disposable fURS groups (p = 0.12; MD = -5.31; 95% CI, -12.08 to 1.46). For hospital stay, there was also no difference between the two groups (p = 0.61; MD = -0.03; 95% CI, -0.17 to 0.10). There was no significant difference in complication rate between the two groups (p = 0.85; OR = 0.95; 95% CI, 0.56 to 1.61). Conclusions: There were no differences in the SFR, operation time, length of hospital stay, and complication rate between reusable and disposable fURS. Disposable fURS may be a comparable alternative to reusable fURS.

Effects of intravesical BCG maintenance therapy duration on recurrence rate in high-risk non-muscle invasive bladder cancer (NMIBC): Systematic review and network meta-analysis according to EAU COVID-19 recommendations.

PURPOSE: During the coronavirus disease 2019 (COVID-19) pandemic, the European Association of Urology (EAU) recommended that courses of intravesical bacillus Calmette-Guérin (BCG) therapy lasting more than 1 year could be safely terminated for patients with high-risk non-muscle-invasive bladder cancer (NMIBC). Thus, we conducted a systematic review and network meta-analysis according to EAU's COVID-19 recommendations. MATERIALS AND METHODS: A systematic review was performed following the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. We conducted a network meta-analysis of recurrence rate in patients with NMIBC receiving induction therapy (M0) and those receiving maintenance therapy lasting 1 year (M1) and more than 1 year (M2). RESULTS: Nineteen studies of 3,957 patients were included for the network meta-analysis. In a node-split forest plot using Bayesian Markov Chain Monte Carlo (MCMC) modeling, there were no differences between the M1 and M2 groups in recurrence rate [odds ratio (OR) 0.95 (0.73-1.2)]. However, recurrence rate in the M0 group was higher than that in the M1 [OR 1.9 (1.5-2.5)] and M2 [OR 2.0 (1.7-2.4)] groups. P-score tests using frequentist inference to rank the treatments in the network demonstrated that the therapy used in the M2 group (P-score 0.8701) was superior to that used in the M1 (P-score 0.6299) and M0 groups (P-score 0). In rank-probability tests using MCMC modeling, the M2 group showed the highest rank, followed by the M1 and M0 groups. CONCLUSION: In the network meta-analysis, there were no differences between those receiving BCG maintenance therapies in terms of recurrence rate. In the rank tests, therapy lasting more than 1-year appears to be most effective. During the COVID-19 pandemic, 1-year maintenance therapy can be used, but after the COVID-19 pandemic, therapy lasting more than 1-year could be beneficial.

Correction: Biochemical recurrence after radical prostatectomy according to nadir prostate specific antigen value.

[This corrects the article DOI: 10.1371/journal.pone.0249709.].

Swing Door Compressive Fracture Technique for Turbinoplasty: Retrospective Study Based on Computed Tomography and NOSE Scale.

BACKGROUND: Treatment of inferior turbinate hypertrophy is performed using different techniques in rhinoplasty. However, the reported results are not consistent. In this study, we aimed to evaluate the outcomes of Swing door compressive fracture (SDCF) technique for turbinoplasty using computed tomography (CT) and Nasal Obstruction Symptom Evaluation (NOSE) scale. METHODS: This study involved retrospective analysis of 24 patients who underwent inferior turbinoplasty using Swing door compressive fracture (SDCF) technique with or without septoplasty. The angle between the inferior turbinate and lateral nasal wall, total area, inferior turbinate area and the area medial to inferior turbinate were measured preoperatively and postoperatively using coronal section CT images for objective evaluation. Moreover, the NOSE scale was used for subjective evaluation. RESULTS: The angle between inferior turbinate and lateral nasal wall was decreased by 25.3% after the treatment (p <0.0001). Inevitably, postoperative total nasal airway area (area 1) did not face a statistically significant change (p = 0.6878). On the other hand, the area of inferior turbinate (area 2) decreased significantly compared to preoperative value (p = 0.0021), while the area 3, the area medial to inferior turbinate was widened 1.5 times postoperatively. The total preoperative NOSE score was moderate (39.58 ± 22.31%) and it was decreased to mild (5.83 ± 8.81%) after the treatment (p <0.0001). CONCLUSIONS: The Swing door compressive fracture (SDCF) technique for turbinoplasty is an effective and straightforward modality. However, the further study involving more patients and longer follow-up period is mandatory. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Klebsiella Aerogenes Infection on the Costochondral Graft of the Nose.

ABSTRACT: Klebsiella aerogenes is a nosocomial and pathogenic bacterium that causes opportunistic infections including most types of infections. After rhinoplasty, the inserted costochondral graft could be a good material for bacterial growth due to less vascularization and difficult-to-reach antibiotics. The unusual bacterial infection should be considered for preventing poor aesthetic results including graft or implant loss when the surgical site infection is uncontrolled despite proper treatment and administration in aesthetic rhinoplasty surgery. The use of appropriate antibiotics for drug sensitivity may be necessary with bacterial culture tests. In this case, an unusual K. aerogenes infection on the costochondral graft of the nose and related treatment course was reported.

Gastric emptying of preoperative carbohydrate in elderly assessed using gastric ultrasonography: A randomized controlled study.

BACKGROUND: Preoperative carbohydrate loading enhances postoperative recovery and reduces patient discomfort. However, gastric emptying of liquids can be delayed in elderly populations. Therefore, this study aimed to evaluate the gastric emptying of 400 mL of a carbohydrate drink ingested 2 hours before surgery in elderly patients. METHODS: In this prospective, randomized controlled study, patients aged >65 years were allocated to either fast from midnight (nil per os [NPO] group, n = 29) or drink 400 mL of a carbohydrate drink 2 hours before surgery (carbohydrate group, n = 29). The gastric antrum was assessed using ultrasonography in the supine position, followed by the right lateral decubitus (RLD) position. The gastric antrum was graded as grade 0 (fluid not seen in both positions), grade 1 (fluid only seen in the RLD position), and grade 2 (fluid seen in both positions). The gastric antral cross-sectional area (CSA) and aspirated residual gastric volume were measured. RESULTS: In 58 patients, the incidence of grade 2 stomach was 13.8% in NPO group and 17.2% in carbohydrate group (P = .790). The gastric antral CSA in the supine position was larger in carbohydrate group than in NPO group (4.42 [3.72-5.18] cm2 vs 5.31 [4.35-6.92] cm2, P = .018). The gastric antral CSA in the RLD position was not different in NPO and carbohydrate groups (P = .120). There was no difference in gastric volume (2 [0-7.5] vs 3 [0-13.4], P = .331) in NPO group versus carbohydrate group. CONCLUSION: The incidence of grade 2 stomach was not different between NPO group and carbohydrate group in elderly patients.

Biochemical recurrence after radical prostatectomy according to nadir prostate specific antigen value.

The hypersensitive prostate specific antigen (PSA) test can measure in 0.01 ng/mL units, and its efficacy for screening after radical prostatectomy (RP) has been reported. In this study, we assessed patients who underwent RP to evaluate whether the nadir value affects biochemical recurrence (BCR). From 1995 to 2014, patients classified as N0 who had negative resection margins and a nadir PSA of less than 0.2 ng/mL were evaluated. The characteristics, pathological outcomes, PSA after RP, and BCR were assessed. A total of 1483 patients were enrolled. Among them, 323 (21.78%) patients showed BCR after RP. The mean age of the BCR group was 63.86±7.31 years, and while that of the no-recurrence group was 64.06±6.82 years (P = 0.645). The mean preoperative PSA of the BCR group was 9.75±6.92 ng/mL and that of the no-recurrence group was 6.71±5.19 ng/mL (P < 0.001). The mean time to nadir (TTN) in the BCR group was 4.64±7.65 months, while that in the no-recurrence group was 7.43±12.46 months (P < 0.001). The mean PSA nadir value was 0.035±0.034 ng/mL in the BCR group and 0.014±0.009 ng/mL in the no-recurrence group (P < 0.001). In multivariable Cox regression analyses, Gleason score, positive biopsy core percentages, minimal invasive surgery, nadir PSA value, and TTN were independently associated with BCR. The mean BCR occurred at 48.23±2.01 months after RP, and there was a significant difference in BCR occurrence according to the nadir PSA value (P < 0.001). A high PSA nadir value and short TTN may predict the risk of BCR after successful RP, aiding the identification of candidates for adjuvant or salvage therapies after RP.

Prognostic Value of Programmed Death Ligand-1 Expression on Tumor-Infiltrating Immune Cells in Patients Treated with Cisplatin-Based Combination Adjuvant Chemotherapy Following Radical Cystectomy for Muscle-Invasive Bladder Cancer: A Retrospective Cohort Study.

PURPOSE: To investigate the prognostic value of programmed death ligand-1 (PD-L1) expression in tumor-infiltrating immune cells (ICs) in men treated with adjuvant chemotherapy (AC) following radical cystectomy (RC) for muscle-invasive bladder cancer (MIBC). MATERIALS AND METHODS: We retrospectively reviewed 219 "high-risk" (≥pT3a and/or pN+) patients who underwent RC and received cisplatin-based AC for MIBC between March 2015 and September 2019. PD-L1 expression was measured using the VENTANA (SP-142) immunohistochemistry assay and categorized into the three groups according to the percentage of the tumor area covered by PD-L1 expression on ICs: IC0 (<1%), IC1 (≥1% and <5%), and IC2/3 (≥5%). Positive PD-L1 expression was defined as IC2/3 (≥5%). Kaplan-Meier survival analysis was used to assess recurrence-free survival (RFS), and Cox proportional hazard models were applied to identify factors predicting tumor recurrence. RESULTS: In the entire cohort, the overall prevalence of PD-L1 IC0, IC1, and IC2/3 was 13.2%, 27.4%, and 59.4%, respectively. During the mean follow-up of 32.5 months, tumor recurrence was detected in 115 (52.5%) patients. On multivariable analysis, tumor stage (≥pT3; P=0.032), positive lymph nodes (P=0.001), and positive PD-L1 on ICs (P=0.005) were independent predictors of tumor recurrence. The 3 year RFS was 54.7% in patients with negative PD-L1 and 31.7% in patients with positive PD-L1. CONCLUSION: PD-L1 is widely expressed in ICs. Positive PD-L1 on ICs was significantly associated with shorter RFS in patients treated with cisplatin-based AC following RC. The present results support the use of adjuvant immunotherapy in "high-risk" patients with PD-L1-expressing ICs.

Radiologic Analysis of Malar Arch Movement in Reduction Malarplasty Without Bony Resection.

BACKGROUND: Reduction malarplasty has been popular among Asians with a wide facial width. In general, malar setback after bony resection is regarded as the standard objective of reduction malarplasty. However, unnecessary bony resection may lead to various postoperative complications. Therefore, we suggest the use of reduction malarplasty without bony resection to achieve a similar narrowing effect of the facial width, based on radiographic analysis of malar arch movement. PATIENTS AND METHODS: This retrospective study analyzed 48 patients with a wide midface who underwent reduction malarplasty between September 2018 and December 2019. We included 40 cases of advancement repositioning malarplasty (AR) without bony resection and 8 cases of setback reduction malarplasty (SR) with bony resection. The three-dimensional position of the malar arch expressed by coordinates (x, y, and z) on three-dimensional computed tomography scans was used to compare the positional change between the surgical methods. The paired t-test, Wilcoxon text, and independent t-test were used in data analysis, and statistical analysis was performed using SPSS 23.0 software. RESULTS: Medial and superior movement of the freed malar arch segment was significantly different between AR and SR (P < 0.05). Although medialization and superiorization were not significantly different between AR and SR, there was a significant difference in anterior-posterior movement between AR and SR (P < 0.05). CONCLUSION: The radiologic analysis based on malar arch movement between AR and SR showed similar narrowing effects on medialization and superiorization of the malar arch regardless of bony resection. Therefore, the AR can be effectively applied in case of arch dominant type or malar asymmetry. In addition, further comprehensive study including analysis on movement of facial soft tissue following malar bony movement is expected based on this study in near future.

Deviated nose: Physiological and pathological changes of the nasal cavity.

Deviated nose is highly challenging in rhinoplasty since the surgeon should consider both aesthetic and functional aspects of the nose. Deviated nose correction is surgically complex, and a thorough understanding of the mechanical and physiological changes of intranasal structures, including the septum and turbinates, is necessary for functional improvement.

Cadaveric study of deep temporal fascia for autologous rhinoplasty grafts: Dimensions of the temporal compartment in Asians.

BACKGROUND: Due to the anatomical complexity of the deep temporal fascia (DTF), practical guidelines for its safe harvest are lacking. However, since the upper temporal compartment (UTC) contains no vital structures, it may provide safe access for DTF harvest. This study aimed to identify the anatomical structures of the temporal compartment in Asian cadavers and to measure their dimensions to enable safe DTF harvest. METHODS: The anatomical structures surrounding the temporal compartment were identified in 27 hemifaces from 15 Korean cadavers. After dissection, digital images were acquired and craniometric landmarks were placed upon them to identify the boundaries of the temporal compartment. The horizontal and vertical lengths of the temporal compartment were measured and their surface areas were computationally assessed. Subsequently, differences in the results by sex were evaluated. RESULTS: The five-layer anatomical structure of the UTC was clearly visualized. The UTC was bounded by the temporal septa superiorly and inferiorly, the innominate fascia laterally, and the DTF medially. No vital structures were present within the UTC. The vertical and horizontal lengths of the UTC were 6.41±0.67 cm and 10.44±0.83 cm, respectively, and the surface area of the UTC was 48.52±5.65 cm2. No statistically significant differences were observed in any dimensions between male and female patients. CONCLUSIONS: During rhinoplasty, DTF can be harvested as an autologous graft material from the UTC. An anatomical understanding of the UTC will aid in the safe and simple harvest of a sufficient amount of DTF.

In Vitro and in Vivo Biocompatibility and Degradability Evaluation of Modified Polydioxanone Plate.

BACKGROUND: Polydioxanone (PDS) has been widely used in the medical field over the past 30 years. In the 2000s, PDS plate began to be used for rhinoplasty and septoplasty. However, in Asia PDS plates are not widely used due to lack of awareness and high prices. The authors devised a method of producing a modified PDS (m-PDS; Rhinoblock Material & Design Co., Gyeonggi-do, Sothh Korea) at low cost, and compared the biocompatibilities and degradabilities of plates produced with m-PDS and commercial PDS plates (Ethicon, Somerville, NJ) in vivo and in vitro. METHODS: The melting point and decomposition rate of m-PDS were determined by differential scanning calorimetry and thermogravimetric analysis and its tensile strength was also measured. Implants (1 cm × 1 cm × 0.15 mm sized) were inserted subcutaneously into mice and harvested en bloc 2, 5, 10, 15, or 25 weeks later. Tissues were stained with hematoxylin and eosin or Masson's trichrome to evaluate inflammation, extracellular matrix deposition, and vascularization, and plate degradability was also assessed. RESULTS: No significant difference was observed between the thermal analysis and tensile test results of m-PDS and PDS plates. m-PDS started to degrade in vivo from around 10 weeks, and commercial PDS plates from around 15 weeks. After 25 weeks in vivo, both products were completely degraded and not observed in tissue slides. Histologic analysis of excised specimens showed m-PDS and PDS were similar in terms of inflammation, extracellular matrix deposition, and vascularization. CONCLUSION: In vivo and in vitro experiments detected no significant difference between the biocompatibilities and degradabilities of modified and commercial PDS plates. The results of this study suggest that the modified PDS can be used to produce versatile, low cost, absorbable graft materials for rhinoplasty and septoplasty.