Objective: With advances in endoscopic surgery, L5–S1 foraminotomy has become a readily accessible surgical technique. However, symptom relief is often short-lived, and recurrence is common. As an alternative, biportal endoscopic fusion at L5–S1 can improve symptoms. However, it can be challenging and may lead to fusion-related complications. Therefore, we aimed to compare 2 procedures for L5–S1 foraminal stenosis. Methods: A total of 37 patients diagnosed with L5–S1 foraminal stenosis were divided into 2 groups for this study. Group 1, comprising 18 patients, underwent L5–S1 foraminotomy via a paraspinal approach from 2017 to 2019. Group 2, comprising 19 patients, underwent biportal endoscopic L5–S1 fusion with the facet-sacrificing approach from January 2021 to August 2023. A comprehensive evaluation of both groups was conducted using various metrics, including image findings, operation time, hospital stay, visual analogue score (VAS) back, VAS leg, Oswestry Disability Index (ODI), and the MacNab criteria. Postsurgical complications were meticulously recorded. The statistical analysis was performed using the Wilcoxon signed-rank test, and differences between the 2 surgical approaches were assessed using the Mann-Whitney U-test. Results: No statistically significant difference was found in VAS back or ODI improvement between the 2 groups. However, the foraminotomy group exhibited a statistically significant advantage in terms of operation time and hospital stay. Conversely, the fusion group demonstrated statistically significant improvements in VAS leg and McNab criteria in comparison to the foraminotomy group. The most prevalent complication observed in the foraminotomy group was early symptom recurrence, while the fusion group experienced complications related to screw-related issues and infections. Conclusion Leg symptoms recurred more frequently in the foraminotomy group. Biportal endoscopic facet-sacrificing transforaminal lumbar interbody fusion surgery has been demonstrated to be a valuable technique for L5–S1 fusion with lower recurrence of leg symptoms; however, it is associated with complications specific to fusion.

Purpose: Autologous arteriovenous fistulas (AVFs) are considered the gold standard for hemodialysis access, with outcomes largely dependent on the surgeon’s experience. Nevertheless, few studies have been conducted on the learning curve of junior vascular surgeons in AVF creation. This study aims to address this by examining the development of surgical skills among junior vascular surgeons. Materials and Methods: A retrospective analysis was conducted on 100 patients who underwent autologous AVF procedures performed by five junior surgeons between January 2018 and December 2023. To establish the cutoff number of cases for the learning curve, we examined the cubic spline curve using the hazard ratio for primary failure. Results: The cutoff number for operation cases was 15.33, and we divided the analysis into a pre-learning curve period (≤15 cases of AVF) and a post-learning curve period (>15 cases of AVF). The 1-year primary patency rate for AVF during the post-learning curve period was 84.0%, which was higher than the 65.5% rate observed during the pre-learning curve period. In a subgroup analysis based on AVF type, the radiocephalic fistula patient group demonstrated a significant increase in 1-year primary patency in the post-learning curve period compared to that in the pre-learning curve period (80.0% vs. 43.0%, log-rank P=0.033). In contrast, there was no significant difference in the primary patency rates between the post- and pre-learning curve periods in the brachiocephalic fistula patient group (90.0% vs. 89.2%, log-rank P=0.930). Conclusion Junior vascular surgeons demonstrated improved primary AVF patency beyond the learning curve benchmark in 15 patients, with particularly notable enhancements in radiocephalic fistulas.

Purpose: Autologous arteriovenous fistulas (AVFs) are considered the gold standard for hemodialysis access, with outcomes largely dependent on the surgeon’s experience. Nevertheless, few studies have been conducted on the learning curve of junior vascular surgeons in AVF creation. This study aims to address this by examining the development of surgical skills among junior vascular surgeons. Materials and Methods: A retrospective analysis was conducted on 100 patients who underwent autologous AVF procedures performed by five junior surgeons between January 2018 and December 2023. To establish the cutoff number of cases for the learning curve, we examined the cubic spline curve using the hazard ratio for primary failure. Results: The cutoff number for operation cases was 15.33, and we divided the analysis into a pre-learning curve period (≤15 cases of AVF) and a post-learning curve period (>15 cases of AVF). The 1-year primary patency rate for AVF during the post-learning curve period was 84.0%, which was higher than the 65.5% rate observed during the pre-learning curve period. In a subgroup analysis based on AVF type, the radiocephalic fistula patient group demonstrated a significant increase in 1-year primary patency in the post-learning curve period compared to that in the pre-learning curve period (80.0% vs. 43.0%, log-rank P=0.033). In contrast, there was no significant difference in the primary patency rates between the post- and pre-learning curve periods in the brachiocephalic fistula patient group (90.0% vs. 89.2%, log-rank P=0.930). Conclusion Junior vascular surgeons demonstrated improved primary AVF patency beyond the learning curve benchmark in 15 patients, with particularly notable enhancements in radiocephalic fistulas.

Purpose: Autologous arteriovenous fistulas (AVFs) are considered the gold standard for hemodialysis access, with outcomes largely dependent on the surgeon’s experience. Nevertheless, few studies have been conducted on the learning curve of junior vascular surgeons in AVF creation. This study aims to address this by examining the development of surgical skills among junior vascular surgeons. Materials and Methods: A retrospective analysis was conducted on 100 patients who underwent autologous AVF procedures performed by five junior surgeons between January 2018 and December 2023. To establish the cutoff number of cases for the learning curve, we examined the cubic spline curve using the hazard ratio for primary failure. Results: The cutoff number for operation cases was 15.33, and we divided the analysis into a pre-learning curve period (≤15 cases of AVF) and a post-learning curve period (>15 cases of AVF). The 1-year primary patency rate for AVF during the post-learning curve period was 84.0%, which was higher than the 65.5% rate observed during the pre-learning curve period. In a subgroup analysis based on AVF type, the radiocephalic fistula patient group demonstrated a significant increase in 1-year primary patency in the post-learning curve period compared to that in the pre-learning curve period (80.0% vs. 43.0%, log-rank P=0.033). In contrast, there was no significant difference in the primary patency rates between the post- and pre-learning curve periods in the brachiocephalic fistula patient group (90.0% vs. 89.2%, log-rank P=0.930). Conclusion Junior vascular surgeons demonstrated improved primary AVF patency beyond the learning curve benchmark in 15 patients, with particularly notable enhancements in radiocephalic fistulas.

Purpose: Autologous arteriovenous fistulas (AVFs) are considered the gold standard for hemodialysis access, with outcomes largely dependent on the surgeon’s experience. Nevertheless, few studies have been conducted on the learning curve of junior vascular surgeons in AVF creation. This study aims to address this by examining the development of surgical skills among junior vascular surgeons. Materials and Methods: A retrospective analysis was conducted on 100 patients who underwent autologous AVF procedures performed by five junior surgeons between January 2018 and December 2023. To establish the cutoff number of cases for the learning curve, we examined the cubic spline curve using the hazard ratio for primary failure. Results: The cutoff number for operation cases was 15.33, and we divided the analysis into a pre-learning curve period (≤15 cases of AVF) and a post-learning curve period (>15 cases of AVF). The 1-year primary patency rate for AVF during the post-learning curve period was 84.0%, which was higher than the 65.5% rate observed during the pre-learning curve period. In a subgroup analysis based on AVF type, the radiocephalic fistula patient group demonstrated a significant increase in 1-year primary patency in the post-learning curve period compared to that in the pre-learning curve period (80.0% vs. 43.0%, log-rank P=0.033). In contrast, there was no significant difference in the primary patency rates between the post- and pre-learning curve periods in the brachiocephalic fistula patient group (90.0% vs. 89.2%, log-rank P=0.930). Conclusion Junior vascular surgeons demonstrated improved primary AVF patency beyond the learning curve benchmark in 15 patients, with particularly notable enhancements in radiocephalic fistulas.

Purpose: Autologous arteriovenous fistulas (AVFs) are considered the gold standard for hemodialysis access, with outcomes largely dependent on the surgeon’s experience. Nevertheless, few studies have been conducted on the learning curve of junior vascular surgeons in AVF creation. This study aims to address this by examining the development of surgical skills among junior vascular surgeons. Materials and Methods: A retrospective analysis was conducted on 100 patients who underwent autologous AVF procedures performed by five junior surgeons between January 2018 and December 2023. To establish the cutoff number of cases for the learning curve, we examined the cubic spline curve using the hazard ratio for primary failure. Results: The cutoff number for operation cases was 15.33, and we divided the analysis into a pre-learning curve period (≤15 cases of AVF) and a post-learning curve period (>15 cases of AVF). The 1-year primary patency rate for AVF during the post-learning curve period was 84.0%, which was higher than the 65.5% rate observed during the pre-learning curve period. In a subgroup analysis based on AVF type, the radiocephalic fistula patient group demonstrated a significant increase in 1-year primary patency in the post-learning curve period compared to that in the pre-learning curve period (80.0% vs. 43.0%, log-rank P=0.033). In contrast, there was no significant difference in the primary patency rates between the post- and pre-learning curve periods in the brachiocephalic fistula patient group (90.0% vs. 89.2%, log-rank P=0.930). Conclusion Junior vascular surgeons demonstrated improved primary AVF patency beyond the learning curve benchmark in 15 patients, with particularly notable enhancements in radiocephalic fistulas.

Bioresorbable vascular scaffold (BRS) is an innovative device that provides structural support and drug release to prevent early recoil or restenosis, and then degrades into nontoxic compounds to avoid late complications related with metallic drug-eluting stents (DESs). BRS has several putative advantages. However, recent randomized trials and registry studies raised clinical concerns about the safety and efficacy of first generation BRS. In addition, the general guidance for the optimal practice with BRS has not been suggested due to limited long-term clinical data in Korea. To address the safety and efficacy of BRS, we reviewed the clinical evidence of BRS implantation, and suggested the appropriate criteria for patient and lesion selection, scaffold implantation technique, and management.
Coronary Disease ; Drug Liberation ; Drug-Eluting Stents ; Humans ; Korea ; Stents ; Thrombosis

The benefits of bilateral cochlear implants (CIs) include better understanding of speech in noise and localization of sound sources. Following the improvement observed in adults, children were also included in the bilateral CIs program. The aim of this study was to investigate the impact of bilateral CIs use on speech perception in quiet and in noise. Four children underwent testing from 9 to 18 months after activation of bilateral hearing. Speech perception tests in quiet and in noise (signal to noise ratio of +10 dB) were performed in all children with the first CI alone and bilaterally. Subjects showed varying degrees of improved performance on speech perception tests in quiet and in noise according to bilateral auditory experience. Bilateral CIs can offer a substantial benefit in speech perception in quiet and in noise. The extent of the advantage, however, may require a more prolonged period of adjustment and learning.
Adult ; Child* ; Cochlear Implantation* ; Cochlear Implants* ; Hearing ; Humans ; Learning ; Noise ; Speech Perception

BACKGROUND AND OBJECTIVES: Vestibular evoked myogenic potential (VEMP) is muscle reflex caused by surface electrodes following repeated high-intensity auditory stimulation. The current study attempted to determine whether VEMP can be consistently evoked from the sternocleidomastoid muscle (SCM) by the 100 dB air-conducted and 50 dB bone-conducted 500 Hz-tone burst. SUBJECTS AND METHOD: Air-conducted and bone-conducted VEMPs in response to 500 Hz-tone burst were recorded from the SCM of 13 normal volunteers. Subjects were seated on their chairs and made to hold their heads turned up as far as possible towards the side, contralateral to the stimulated ear voluntarily. Two different sound durations (rise/fall time=2 msec, plateau time=2 msec[2/2] and rise/fall time=5 msec, plateau time=5 msec[5/5]) were presented through a insertphone or bone vibrators. Latencies and amplitudes of p13 and n23 responses were measured. RESULTS: All normal volunteers showed p13-n23 responses to 50 dB bone-conducted tone burst as well as to 100 dB air-conducted tone burst. The values of latency of p13 and n23 were the most reliable at 5/5 air-conducted in evaluation by coefficiency of variance. Mean p13 and N23 latencies by airconducted tone burst were significantly longer than those of bone-conducted. Mean p13-n23 amplitudes by air-conducted tone burst were significantly larger than those by bone-conducted at 2/2 sound duration. CONCLUSION: VEMP could be consis-tently evoked by the 100 dB air-conducted and 50 dB bone-conducted 500 Hz-tone burst, especially at 5/5 air-conducted.
Acoustic Stimulation ; Ear ; Electrodes ; Head ; Healthy Volunteers ; Reflex ; Vestibular Evoked Myogenic Potentials*

BACKGROUND AND OBJECTIVES: The aim of this study was to assess the accuracy of threshold estimates determined by the auditory steady-state response (ASSR) in a group of sedated infants and young children with a range of hearing losses. MATERIALS AND METHOD: Two studies were performed because the behavioral audiometric information was not available from infants and young children. In the first study, a retrospective analysis was performed for 36 children (mean age: 3 years 4 months) who had completed auditory brainstem response (ABR) and pure tone audiometry to verify that ABR threshold is a good predictor for pure tone threshold in our laboratory. The ABR thresholds to 500 Hz, 1000 Hz tone-pip and click were compared with behavioral thresholds. In the second study, a prospective analysis of 23 children (mean age: 12 months), the ABR thresholds to 500 Hz, 1000 Hz tone-pip and click were compared with ASSR thresholds to amplitude and frequency modulated tones. RESULTS: The first study in which strong correlations were found between ABR and pure tone thresholds (r> or =0.92) demonstrated that ABR thresholds could be used to predict the pure tone thresholds. The second study which showed that ASSR thresholds were highly correlated with ABR thresholds (r> or =0.93) indicated that ASSR thresholds provided reliable audiometric information in infants and young children. CONCLUSION: These studies showed that ASSR could be used to estimate hearing thresholds with reliable accuracy in infants and young children.
Audiometry ; Child* ; Evoked Potentials, Auditory, Brain Stem* ; Hearing ; Hearing Loss ; Humans ; Infant* ; Prospective Studies ; Retrospective Studies