AIM: To evaluate the nature of the 'learning curve' for laparoscopy-assisted distal gastrectomy (LADG) with systemic lymphadenectomy for early gastric cancer. METHODS: The data of 90 consecutive patients with ...AIM: To evaluate the nature of the 'learning curve' for laparoscopy-assisted distal gastrectomy (LADG) with systemic lymphadenectomy for early gastric cancer. METHODS: The data of 90 consecutive patients with early gastric cancer who underwent LADG with systemic lymphadenectomy between April 2003 and November 2004 were reviewed. The 90 patients were divided into 9 sequential groups of 10 cases in each group and the average operative time of these 9 groups were determined. Other learning indicators, such as transfusion requirements, conversion rates to open surgery, postoperative complication, time to first flatus, and postoperative hospital stay, were evaluated. RESULTS: After the first 10 LADGs, the operative time reached its first plateau (230-240 min/operation) and then reached a second plateau (＜200 min/operation) for the final 30 cases. Although a significant improvement in the operative time was noted after the first 50 cases, there were no significant differences in transfusion requirements, conversion rates to open surgery, postoperative complications, time to first flatus, or postoperative hospital stay between the groups. CONCLUSION: Based on operative time analysis, this study show that experience of 50 cases of LADG with systemic lymphadenectomy for early gastric cancer is required to achieve optimum proficiency.展开更多
Objectives： This study aimed to compare the learning curves of percutaneous endoscopic lumbar discectomy （PELD） in a transforaminal approach at the L4/5 and L5/S1 levels. Methods： We retrospectively reviewed the f...Objectives： This study aimed to compare the learning curves of percutaneous endoscopic lumbar discectomy （PELD） in a transforaminal approach at the L4/5 and L5/S1 levels. Methods： We retrospectively reviewed the first 60 cases at the L4/5 level （Group I） and the first 60 cases at the L5/S1 level （Group II） of PELD performed by one spine surgeon. The patients were divided into subgroups A, B, and C （Group I： A cases 1-20, B cases 21-40, C cases 41-60; Group I1： A cases 1-20, B cases 21-40, C cases 41-60）. Operation time was thoroughly analyzed. Results： Compared with the L4/5 level, the learning curve of transforaminal PELD at the L5/S1 level was flatter. The mean operation times of Groups IA, IB, and IC were （88.75±17.02）, （67.75±6.16）, and （64.85±7.82） min, respectively. There was a significant difference between Groups A and B （P〈0.05）, but no significant difference between Groups B and C （P=-0.20）. The mean operation times of Groups IIA, liB, and IIC were （117.25±13.62）, （109.50±11.20）, and （92.15±11.94） rain, respectively. There was no significant difference between Groups A and B （P=0.06）, but there was a significant difference between Groups B and C （P〈0.05）. There were 6 cases of postoperative dysesthesia （POD） in Group I and 2 cases in Group IIA （P=-0.27）. There were 2 cases of residual disc in Group I, and 4 cases in Group II （P=0.67）. There were 3 cases of recurrence in Group I, and 2 cases in Group II （P〉0.05）. Conclusions： Compared with the L5/S1 level, the learning curve of PELD in a transforaminal approach at the L4/5 level was steeper, suggesting that the L4/5 level might be easier to master after short-term professional training.展开更多
To analyze the learning curve for cancer control from an initial 250 cases （Group I） and subsequent 250 cases （Group II） of robotic-assisted laparoscopic radical prostatectomy （RALP） performed by a single surgeo...To analyze the learning curve for cancer control from an initial 250 cases （Group I） and subsequent 250 cases （Group II） of robotic-assisted laparoscopic radical prostatectomy （RALP） performed by a single surgeon. Five hundred consecutive patients with clinically localized prostate cancer received RALP and were evaluated. Surgical parameters and perioperative complications were compared between the groups, Positive surgical margin （PSM） and biochemical recurrence （BCR） were assessed as cancer control outcomes. Patients in Group II had significantly more advanced prostate cancer than those in Group I （22.2% vs 14.2%, respectively, with Gleason score 8-10, P = 0.033; 12.8% vs 5.6%, respectively, with clinical stage T3, P = 0.017）. The incidence of PSM in pT3 was decreased significantly from 49% in Group I to 32.6% in Group Ih A meaningful trend was noted for a decreasing PSM rate with each consecutive group of 50 cases, including pT3 and high-risk patients. Neurovascular bundle （NVB） preservation was significantly influenced by the PSM in high-risk patients （84.1% in the preservation group vs 43.9% in the nonpreservation group）. The 3-year, 5-year, and 7-year BCR-free survival rates were 79.2%, 75.3%, and 70.2%, respectively. In conclusion, the incidence of PSM in pT3 was decreased significantly after 250 cases. There was a trend in the surgical learning curve for decreasing PSM with each group of 50 cases. NVB preservation during RALP for the high-risk group is not suggested due to increasing PSM.展开更多
Surgical innovation and pioneering are important for improving patient outcome, but can be associated with learning curves. Although learning curves in surgery are a recognized problem, the impact of surgical learning...Surgical innovation and pioneering are important for improving patient outcome, but can be associated with learning curves. Although learning curves in surgery are a recognized problem, the impact of surgical learning curves is increasing, due to increasing complexity of innovative surgical procedures, the rapid rate at which new interventions are implemented and a decrease in relative effectiveness of new interventions compared to old interventions. For minimally invasive esophagectomy(MIE), there is now robust evidence that implementation can lead to significant learning associated morbidity(morbidity during a learning curve, that could have been avoided if patients were operated by surgeons that have completed the learning curve). This article provides an overview of the evidence of the impact of learning curves after implementation of MIE. In addition, caveats for implementation and available evidence regarding factors that are important for safe implementation and safe pioneering of MIE are discussed.展开更多
BACKGROUND In robot-assisted(RA)spine surgery,the relationship between the surgical outcome and the learning curve remains to be evaluated.AIM To analyze the learning curve of RA pedicle screw fixation(PSF)through fit...BACKGROUND In robot-assisted(RA)spine surgery,the relationship between the surgical outcome and the learning curve remains to be evaluated.AIM To analyze the learning curve of RA pedicle screw fixation(PSF)through fitting the operation time curve based on the cumulative summation method.METHODS RA PSFs that were initially completed by two surgeons at the Beijing Jishuitan Hospital from July 2016 to March 2019 were analyzed retrospectively.Based on the cumulative sum of the operation time,the learning curves of the two surgeons were drawn and fit to polynomial curves.The learning curve was divided into the early and late stages according to the shape of the fitted curve.The operation time and screw accuracy were compared between the stages.RESULTS The turning point of the learning curves from Surgeons A and B appeared in the 18th and 17th cases,respectively.The operation time[150(128,188)min vs 120(105,150)min,P=0.002]and the screw accuracy(87.50%vs 96.30%,P=0.026)of RA surgeries performed by Surgeon A were significantly improved after he completed 18 cases.In the case of Surgeon B,the operation time(177.35±28.18 min vs 150.00±34.64 min,P=0.024)was significantly reduced,and the screw accuracy(91.18%vs 96.15%,P=0.475)was slightly improved after the surgeon completed 17 RA surgeries.CONCLUSION After completing 17 to 18 cases of RA PSFs,surgeons can pass the learning phase of RA technology.The operation time is reduced afterward,and the screw accuracy shows a trend of improvement.展开更多
This study was performed to investigate the learning curve of transurethral enucleation with bipolar energy(TUEB)for benignprostatic hyperplasia.The study involved 494 consecutive patients who underwent TUEB for benig...This study was performed to investigate the learning curve of transurethral enucleation with bipolar energy(TUEB)for benignprostatic hyperplasia.The study involved 494 consecutive patients who underwent TUEB for benign prostatic hyperplasia fromAugust 2018 to March 2022 by one surgeon(SJJ,Seoul National University Bundang Hospital,Seongnam,Korea).The patientswere followed up at 1 week,1 month,3 months,and 6 months postoperatively.To evaluate the learning curve of TUEB,perioperativeparameters including the enucleation ratio(enucleated tissue weight/transitional zone volume),TUEB efficiency(enucleatedtissue weight/operation time),and enucleation efficiency(enucleated tissue weight/enucleation time)were analyzed.Functionaloutcomes and postoperative complications were also assessed,including the International Prostate Symptom Score(IPSS),IPSSquality-of-life(QoL)score,and uroflowmetry outcomes.The patients’median age was 72(interquartile range[IQR]:66–78)years,and the estimated prostate volume and transitional zone volume were 63.0(IQR:46.0–90.6)ml and 37.1(IQR:24.0–60.0)ml,respectively.The enucleation ratio,TUEB efficiency,and enucleation efficiency were 0.60(IQR:0.46–0.54)g ml−1,0.33(IQR:0.22–0.46)g min−1,and 0.50(IQR:0.35–0.72)g min−1,respectively,plateauing after 70 cases.The functional outcomes,including total IPSS,IPSS QoL score,and uroflowmetry outcomes,significantly improved at 6 months after TUEB(all P<0.05),but without significant differences over the learning curve.Sixty-five(13.2%)patients developed complications after TUEB,21.5%of whom experienced major complications(Clavien–Dindo grade≥3).The rate of major complications declined as the number ofTUEB cases increased(P=0.013).Our results suggest that the efficiency of TUEB stabilized within 70 procedures.展开更多
Deep neural networks are gaining importance and popularity in applications and services.Due to the enormous number of learnable parameters and datasets,the training of neural networks is computationally costly.Paralle...Deep neural networks are gaining importance and popularity in applications and services.Due to the enormous number of learnable parameters and datasets,the training of neural networks is computationally costly.Parallel and distributed computation-based strategies are used to accelerate this training process.Generative Adversarial Networks(GAN)are a recent technological achievement in deep learning.These generative models are computationally expensive because a GAN consists of two neural networks and trains on enormous datasets.Typically,a GAN is trained on a single server.Conventional deep learning accelerator designs are challenged by the unique properties of GAN,like the enormous computation stages with non-traditional convolution layers.This work addresses the issue of distributing GANs so that they can train on datasets distributed over many TPUs(Tensor Processing Unit).Distributed learning training accelerates the learning process and decreases computation time.In this paper,the Generative Adversarial Network is accelerated using the distributed multi-core TPU in distributed data-parallel synchronous model.For adequate acceleration of the GAN network,the data parallel SGD(Stochastic Gradient Descent)model is implemented in multi-core TPU using distributed TensorFlow with mixed precision,bfloat16,and XLA(Accelerated Linear Algebra).The study was conducted on the MNIST dataset for varying batch sizes from 64 to 512 for 30 epochs in distributed SGD in TPU v3 with 128×128 systolic array.An extensive batch technique is implemented in bfloat16 to decrease the storage cost and speed up floating-point computations.The accelerated learning curve for the generator and discriminator network is obtained.The training time was reduced by 79%by varying the batch size from 64 to 512 in multi-core TPU.展开更多
AIM:To explore the learning curve for ophthalmologists at the start of laser peripheral iridectomy(LPI)training.METHODS:The learning curve of 4 doctor groups without previous LPI experience was studied.Three main para...AIM:To explore the learning curve for ophthalmologists at the start of laser peripheral iridectomy(LPI)training.METHODS:The learning curve of 4 doctor groups without previous LPI experience was studied.Three main parameters of LPI were reviewed:total energy,argon energy and neodymium-doped yttrium aluminum garnet(Nd:YAG)energy.Procedures were evaluated in cohorts of 20 cases to identify the turning points of the three variables.RESULTS:There was no significant difference in terms of age or eye among the 4 doctor groups.There were stable trends on the learning curve for the Doctor A and C groups regarding total energy and argon energy.In addition,the turning points on the learning curve were determined after the 20th procedure for the Doctor B and D groups regarding total energy and argon energy.Moreover,the Nd:YAG energy was relatively stable since the first procedure.CONCLUSION:It requires approximately 20 procedures for a beginner to reach a turning point on the learning curve regarding LPI.It can serve as a point of reference or guideline for training beginners to perform LPI.展开更多
AIM： To use the cumulative sum analysis score（CUSUM） to construct objectively the learning curve of phacoemulsification competency.METHODS： Three second-year residents and an experienced consultant were monitored ...AIM： To use the cumulative sum analysis score（CUSUM） to construct objectively the learning curve of phacoemulsification competency.METHODS： Three second-year residents and an experienced consultant were monitored for a series of 70 phacoemulsification cases each and had their series analysed by CUSUM regarding posterior capsule rupture（PCR） and best-corrected visual acuity. The acceptable rate for PCR was 〈5%（lower limit h） and the unacceptable rate was 〉10%（upper limit h）. The acceptable rate for bestcorrected visual acuity worse than 20/40 was 〈10%（lower limit h） and the unacceptable rate was 〉20%（upper limit h）. The area between lower limit h and upper limit h is called the decision interval. RESULTS： There was no statistically significant difference in the mean age, sex or cataract grades between groups. The first trainee achieved PCR CUSUM competency at his 22 nd case. His best-corrected visual acuity CUSUM was in the decision interval from his third case and stayed there until the end, never reaching competency. The second trainee achieved PCR CUSUM competency at his 39^ th case. He could reach best-corrected visual acuity CUSUM competency at his 22 ^nd case. The third trainee achieved PCR CUSUM competency at his 41 st case. He reached bestcorrected visual acuity CUSUM competency at his 14 ^th case.CONCLUSION： The learning curve of competency in phacoemulsification is constructed by CUSUM and in average took 38 cases for each trainee to achieve it.展开更多
To estimate the short-term results of robot-assisted laparoscopic radical prostatectomy(RALRP)during the learning curve,in terms of surgical,oncological and functional outcomes,we conducted a prospective survey on RAL...To estimate the short-term results of robot-assisted laparoscopic radical prostatectomy(RALRP)during the learning curve,in terms of surgical,oncological and functional outcomes,we conducted a prospective survey on RALRP.From July 2007,a single surgeon performed 63 robotic prostatectomies using the same operative technique.Perioperative data,including pathological and early functional results of the patient,were collected prospectively and analyzed.Along with the accumulation of the cases,the total operative time,setup time,console time and blood loss were significantly decreased.No major complication was present in any patient.Transfusion was needed in six patients;all of them were within the initial 15 cases.The positive surgical margin rate was 9.8%(5/51)in pT2 disease.The most frequent location of positive margin in this stage was the lateral aspect(60%),but in pT3 disease multiple margins were the most frequent(41.7%).Overall,53(84.1%)patients had totally continent status and the median time to continence was 6.56 weeks.Among 17 patients who maintained preoperative sexual activity(Sexual Health Inventory for Men≥17),stage below pT2,followed up for>6 months with minimally one side of neurovascular bundle preservation procedure,12(70.6%)were capable of intercourse postoperatively,and the mean time for sexual intercourse after operation was 5.7 months.In this series,robotic prostatectomy was a feasible and reproducible technique,with a short learning curve and low perioperative complication rate.Even during the initial phase of the learning curve,satisfactory results were obtained with regard to functional and oncological outcome.展开更多
AIM: To identify instrument holding archetypes used by experienced surgeons in order to develop a universal language and set of validated techniques that can be utilized in manual small incision cataract surgery(MSICS...AIM: To identify instrument holding archetypes used by experienced surgeons in order to develop a universal language and set of validated techniques that can be utilized in manual small incision cataract surgery(MSICS) curricula. METHODS: Experienced cataract surgeons performed five MSICS steps(scleral incision, scleral tunnel, side port, corneal tunnel, and capsulorhexis) in a wet lab to record surgeon hand positions. Images and videos were taken during each step to identify validated hand position archetypes.RESULTS: For each MSICS step, one or two major archetypes and key modifying variables were observed, including tripod for scleral incision, tripod-thumb bottom for scleral tunnel, underhand-index to thumb grip for side port, index-contact tripod for corneal entry, and tripodforceps for capsulorhexis. Key differences were noted in thumb placement and number of fingers supporting the instrument, and modifying variables included index finger curvature and amount of flexion.CONCLUSION: Identification of optimal hand positions and development of a formal nomenclature has the potential to help trainees adopt hand positions in an informed manner, influence instrument design, and improve surgical outcomes.展开更多
BACKGROUND Robotic pancreaticoduodenectomy(RPD)can achieve similar surgical results to open and PD;however,RPD has a long learning curve and operation time(OT).To address this issue,we have summarized a surgical path ...BACKGROUND Robotic pancreaticoduodenectomy(RPD)can achieve similar surgical results to open and PD;however,RPD has a long learning curve and operation time(OT).To address this issue,we have summarized a surgical path to shorten the surgical learning curve and OT.AIM To investigate the effective learning curve of a“G”-shaped surgical approach in RPD for patients.METHODS A total of 60 patients,who received“G”-shaped RPD(GRPD)by a single surgeon in the First Hospital of Shanxi Medical University from May 2017 to April 2020,were included in this study.The OT,demographic data,intraoperative blood loss,complications,hospitalization time,and pathological results were recorded,and the cumulative sum(CUSUM)analysis was performed to evaluate the learning curve for GRPD.RESULTS According to the CUSUM analysis,the learning curve for GRPD was grouped into two phases:The early and late phases.The OT was 480±81.65 min vs 331±76.54 min,hospitalization time was 22±4.53 d vs 17±6.08 d,and blood loss was 308±54.78 mL vs 169.2±35.33 mL in the respective groups.Complications,including pancreatic fistula,bile leakage,reoperation rate,postoperative death,and delayed gastric emptying,were significantly decreased after this surgical technique.CONCLUSION GRPD can improve the learning curve and operative time,providing a new method for shortening the RPD learning curve.展开更多
The learning curve in minimally invasive colorectal surgery is a constant subject of discussion in the literature.Discordant data likely reflects the varying degrees of each surgeon’s experience in colorectal,laparos...The learning curve in minimally invasive colorectal surgery is a constant subject of discussion in the literature.Discordant data likely reflects the varying degrees of each surgeon’s experience in colorectal,laparoscopic or robotic surgery.Several factors are necessary for a successful minimally invasive colorectal surgery training program,including:Compliance with oncological outcomes;dissection along the embryological planes;constant presence of an expert tutor;periodic discussion of the morbidity and mortality rate;and creation of a dedicated,expert team.展开更多
Background: Rhinoplasty is a complex surgical procedure that requires critical analysis and precise design before surgery, making it a challenging operation for both the surgical team and medical educators. This study...Background: Rhinoplasty is a complex surgical procedure that requires critical analysis and precise design before surgery, making it a challenging operation for both the surgical team and medical educators. This study aimed to evaluate the impact of 3D design involvement on learning curves and to establish a more effective method for rhinoplasty education.Methods: Surgeons who participated in an educational program were divided into two groups. The experimental group was involved in the 3D design before the operation, and the control group was asked to review the rhinoplasty atlas. A self-assessment questionnaire was used to evaluate the learning curve of the eight rhinoplasty procedures for each surgeon, and the overall satisfaction rate data were also collected.Results: The self-assessment scores in both groups showed an increasing trend from the first to the eighth operation. The mean scores of the experimental group were significantly higher than those of the control group at the fifth operation(P=0.01). The satisfaction rate of the experimental group(91.7%) was higher than that of the control group(54.5%).Conclusion: The 3D imaging system can improve the learning curve and satisfaction rate of rhinoplasty education,proving that it is an easy and effective tool for medical education.展开更多
Objectives: To summarize the current status and outlook of pancreatic duct drainage in the learning curve period of laparoscopic pancreaticoduodenectomy (LPD). Methods: By searching the literature related to the effic...Objectives: To summarize the current status and outlook of pancreatic duct drainage in the learning curve period of laparoscopic pancreaticoduodenectomy (LPD). Methods: By searching the literature related to the efficacy analysis of internal versus external pancreatic duct drainage in pancreaticoduodenectomy (OPD) and the learning curve period of laparoscopic pancreaticoduodenectomy in recent years at home and abroad and making a review. Results: Because of the complexity of the LPD surgical procedure, the high technical requirements and the high complication rate, it is necessary for the operator and his/her team to carry out a certain number of cases to pass through the learning curve in order to have a basic mastery of the procedure. In recent years, more and more pancreatic surgeons have begun to promote and use pancreatic duct drains. However, no consensus conclusion has been reached on whether to choose internal or external drainage for pancreatic duct placement and drainage in LPD. Conclusions: Intraoperative application of pancreatic duct drainage reduces the incidence of pancreatic fistula during the learning curve of laparoscopic pancreaticoduodenectomy. However, external pancreatic duct drainage and internal pancreatic duct drainage have both advantages and disadvantages, so when choosing the drainage method, one should choose the appropriate drainage method in conjunction with one’s own conditions, so as to reduce the incidence of complications.展开更多
Objective Single-stage surgery combining embolisation and microsurgery has been increasingly used as a stand-alone procedure to cure complex AVMs.This study aimed to investigate the learning curve and embolisation str...Objective Single-stage surgery combining embolisation and microsurgery has been increasingly used as a stand-alone procedure to cure complex AVMs.This study aimed to investigate the learning curve and embolisation strategy for single-stage surgery for AVMs.Methods This prospective cohort study used data from the nationwide Multimodality Treatment for Brain Arteriovenous Malformations(MATCH)registry in China,conducted between August 2011 and December 2023.A total of 213 complex AVMs were divided into two groups.Group 1 included the first 25 patients.The 188 cases in group 2 included patients numbered 26-213.A case-crossover design was employed to evaluate the influence of complications,unfavourable outcomes and worsening modified Rankin Scale(mRS)score.Cumulative summation analysis was performed to assess the learning curve.Results The rate of major complications decreased from 52.00%in group 1 to 34.57%in group 2(p=0.089),while the rate of unfavourable outcomes decreased from 44.00%in group 1 to 18.62%in group 2(p=0.004).The distribution of the three preoperative embolisation strategies was as follows:curative:72.00%and 19.15%,palliative:24.00%and 67.55%,and targeted:4.00%and 13.30%,respectively(p<0.001).Multivariable regression analysis showed that surgeon experience was associated with a lower rate of unfavourable outcomes(p=0.022,OR=0.333).The mean follow-up duration was 49.90±20.54 months.The follow-up mRS score of 5-6 decreased from 9.09%in group 1 to 0.8%in group 2(p=0.035).Conclusions Performing single-stage combined surgery in 25 AVM cases is necessary to achieve reproducibility.Rates of major complications and unfavourable outcomes decreased significantly after the first 50 procedures.Palliative and targeted embolisation strategies are associated with a lower rate of unfavourable outcomes.展开更多
Background:Pancreatoduodenectomy(PD)is a major surgical procedure that is still mostly performed via open approach[open PD(OPD)]since the laparoscopic approach(LA)is limited outside specialised centers.Robot-assisted ...Background:Pancreatoduodenectomy(PD)is a major surgical procedure that is still mostly performed via open approach[open PD(OPD)]since the laparoscopic approach(LA)is limited outside specialised centers.Robot-assisted PD(RPD)appears to decrease the difficulties associated with LA.However,previously published studies are partly biased because they stem from institutions with extensive access to robotic platforms(ARPs).The present study aims to analyse the safety of RPD compared with OPD and the specific learning curve when performed with limited ARP.Methods:This prospective single-center study was conducted in a high-volume pancreatic surgery center but with limited ARP between May 2018 and October 2023.Safety(primary endpoint:90-day mortality)was assessed using propensity score matching(2:1)to compare RPD and OPD.The learning curve was evaluated using cumulative sum(CUSUM)control chart analysis(split into three consecutive periods of 20 patients),focusing on operative time and complications.Results:A total of 354 PD were analysed,of which 60(17%)were RPD.A matched cohort of 120 OPD was used for comparison.The conversion rate was 15%in the RPD group.The 90-day mortality rate was 5%and 8.3%for RPD and OPD,respectively(P=0.55).The RPD learning curve showed a reduction in hospital stay(19.9 vs.25.3 vs.14.5 days,P=0.17)and a decrease in post-operative complications with increasing experience.Conclusions:Even with limited ARP,setting up a robotic program for PD is feasible and safe but it requires a learning curve of 40 patients.During this initial phase,careful patient selection is mandatory.展开更多
Background Microendoscopic discectomy （MED） is a minimally invasive operation that allows rapid recovery from surgery for lumbar disc herniation, but has replaced traditional open surgery in few hospitals because mo...Background Microendoscopic discectomy （MED） is a minimally invasive operation that allows rapid recovery from surgery for lumbar disc herniation, but has replaced traditional open surgery in few hospitals because most surgeons avoid its long learning curve. We evaluated the effectiveness and safety of lumbar MED at stages of spinal surgeons＇ learning curve. Methods Fifty patients receiving MED from June 2002 to February 2003 were divided into chronological groups of ten each： A-E. The control group F was ten MED patients treated later by the same medical team （September-October 2006）. All operations were performed by the same team of spinal surgeons with no MED experience before June 2002. We compared groups by operation time, blood loss, complications and need for open surgery after MED failure. Results Operation times by group were： A, （107±14） minutes; B, （85±13） minutes; C, （55±19） minutes; D, （52±12） minutes; E, （51±13） minutes; and F, （49±15） minutes. Blood loss were： A, （131±73） ml; B, （75±20） ml; C, （48±16） ml; D, （44±17） ml; E, （45±18） ml; and F, （45±16） ml. Both operation time and blood loss in groups C, D, E and F were smaller and more stable compared with groups A and B. Japanese Orthopedic Association assessment （JOA） score of each group in improvement rate immediately and one year after operation were as follows （in percentage）： A, （79.8±8.8）/（89.8±7.7）; B, （78.6±8.5）/（88.5±7.8）; C, （80.8±11.3）/（90.8±6.7）; D, （77.7±11.4）/（88.9±9.3）; E, （84.0±8.7）/（89.6±9.0）; and F, （77.8±11.6）/ （86.9±8.4）. Groups showed no statistical difference in improvement rates. Complications developed in three patients in group A, two in group B, and none in the other groups. Conclusions Spinal surgeons performing MED become proficient after 10-20 operations, when their skill becomes fairly sophisticated. Patients＇ improvement rate is the same regardless of surgeons＇ phase of learning curve.展开更多
Background Spine surgery using computer-assisted navigation （CAN） has been proven to result in low screw misplacement rates, low incidence of radiation exposure and excellent operative field viewing versus the conve...Background Spine surgery using computer-assisted navigation （CAN） has been proven to result in low screw misplacement rates, low incidence of radiation exposure and excellent operative field viewing versus the conventional intraoperative image intensifier （CⅢ）. However, as we know, few previous studies have described the learning curve of CAN in spine surgery.Methods We performed two consecutive case cohort studies on pedicel screw accuracy and operative time of two spine surgeons with different experience backgrounds, A and B, in one institution during the same period. Lumbar pedicel screw cortical perforation rate and operative time of the same kind of operation using CAN were analyzed and compared using CⅢ for the two surgeons at initial, 6 months and 12 months of CAN usage.Results CAN spine surgery had an overall lower cortical perforation rate and less mean operative time compared with CⅢ for both surgeon A and B cohorts when total cases of four years were included. It missed being statistically significant,with 3.3% versus 4.7% （P=0.191） and 125.7 versus 132.3 minutes （P=0.428） for surgeon A and 3.6% versus 6.4%（P=0.058）, and 183.2 versus 213.2 minutes （P=0.070） for surgeon B. in an attempt to demonstrate the learning curve,the cases after 6 months of the CAN system in each surgeon＇s cohort were compared. The perforation rate decreased by 2.4% （P=0.039） and 4.3% （P=0.003） and the operative time was reduced by 31.8 minutes （P=0.002） and 14.4 minutes （P=0.026） for the CAN groups of surgeons A and B, respectively. When only the cases performed after 12 months using the CAN system were considered, the perforation rate decreased by 3.9% （P=0.006） and 5.6% （P 〈0.001） and the operative time was reduced by 20.9 minutes （P 〈0.001） and 40.3 minutes （P 〈0.001） for the CAN groups of surgeon A and B, respectively.Conclusions In the long run, CAN spine surgery decreased the lumbar screw cortical perforation rate and operative time. The learning curve showed a sharp drop after 6 months of using CAN that plateaued after 12 months; which was demonstrated by both perforation rate and operative time data. Careful analysis of the data showed CAN is especially useful for less experienced surgeon to reduce perforation rate and intraoperative time, although further comparative studies are anticipated.展开更多
文摘AIM: To evaluate the nature of the 'learning curve' for laparoscopy-assisted distal gastrectomy (LADG) with systemic lymphadenectomy for early gastric cancer. METHODS: The data of 90 consecutive patients with early gastric cancer who underwent LADG with systemic lymphadenectomy between April 2003 and November 2004 were reviewed. The 90 patients were divided into 9 sequential groups of 10 cases in each group and the average operative time of these 9 groups were determined. Other learning indicators, such as transfusion requirements, conversion rates to open surgery, postoperative complication, time to first flatus, and postoperative hospital stay, were evaluated. RESULTS: After the first 10 LADGs, the operative time reached its first plateau (230-240 min/operation) and then reached a second plateau (＜200 min/operation) for the final 30 cases. Although a significant improvement in the operative time was noted after the first 50 cases, there were no significant differences in transfusion requirements, conversion rates to open surgery, postoperative complications, time to first flatus, or postoperative hospital stay between the groups. CONCLUSION: Based on operative time analysis, this study show that experience of 50 cases of LADG with systemic lymphadenectomy for early gastric cancer is required to achieve optimum proficiency.
文摘Objectives： This study aimed to compare the learning curves of percutaneous endoscopic lumbar discectomy （PELD） in a transforaminal approach at the L4/5 and L5/S1 levels. Methods： We retrospectively reviewed the first 60 cases at the L4/5 level （Group I） and the first 60 cases at the L5/S1 level （Group II） of PELD performed by one spine surgeon. The patients were divided into subgroups A, B, and C （Group I： A cases 1-20, B cases 21-40, C cases 41-60; Group I1： A cases 1-20, B cases 21-40, C cases 41-60）. Operation time was thoroughly analyzed. Results： Compared with the L4/5 level, the learning curve of transforaminal PELD at the L5/S1 level was flatter. The mean operation times of Groups IA, IB, and IC were （88.75±17.02）, （67.75±6.16）, and （64.85±7.82） min, respectively. There was a significant difference between Groups A and B （P〈0.05）, but no significant difference between Groups B and C （P=-0.20）. The mean operation times of Groups IIA, liB, and IIC were （117.25±13.62）, （109.50±11.20）, and （92.15±11.94） rain, respectively. There was no significant difference between Groups A and B （P=0.06）, but there was a significant difference between Groups B and C （P〈0.05）. There were 6 cases of postoperative dysesthesia （POD） in Group I and 2 cases in Group IIA （P=-0.27）. There were 2 cases of residual disc in Group I, and 4 cases in Group II （P=0.67）. There were 3 cases of recurrence in Group I, and 2 cases in Group II （P〉0.05）. Conclusions： Compared with the L5/S1 level, the learning curve of PELD in a transforaminal approach at the L4/5 level was steeper, suggesting that the L4/5 level might be easier to master after short-term professional training.
文摘To analyze the learning curve for cancer control from an initial 250 cases （Group I） and subsequent 250 cases （Group II） of robotic-assisted laparoscopic radical prostatectomy （RALP） performed by a single surgeon. Five hundred consecutive patients with clinically localized prostate cancer received RALP and were evaluated. Surgical parameters and perioperative complications were compared between the groups, Positive surgical margin （PSM） and biochemical recurrence （BCR） were assessed as cancer control outcomes. Patients in Group II had significantly more advanced prostate cancer than those in Group I （22.2% vs 14.2%, respectively, with Gleason score 8-10, P = 0.033; 12.8% vs 5.6%, respectively, with clinical stage T3, P = 0.017）. The incidence of PSM in pT3 was decreased significantly from 49% in Group I to 32.6% in Group Ih A meaningful trend was noted for a decreasing PSM rate with each consecutive group of 50 cases, including pT3 and high-risk patients. Neurovascular bundle （NVB） preservation was significantly influenced by the PSM in high-risk patients （84.1% in the preservation group vs 43.9% in the nonpreservation group）. The 3-year, 5-year, and 7-year BCR-free survival rates were 79.2%, 75.3%, and 70.2%, respectively. In conclusion, the incidence of PSM in pT3 was decreased significantly after 250 cases. There was a trend in the surgical learning curve for decreasing PSM with each group of 50 cases. NVB preservation during RALP for the high-risk group is not suggested due to increasing PSM.
文摘Surgical innovation and pioneering are important for improving patient outcome, but can be associated with learning curves. Although learning curves in surgery are a recognized problem, the impact of surgical learning curves is increasing, due to increasing complexity of innovative surgical procedures, the rapid rate at which new interventions are implemented and a decrease in relative effectiveness of new interventions compared to old interventions. For minimally invasive esophagectomy(MIE), there is now robust evidence that implementation can lead to significant learning associated morbidity(morbidity during a learning curve, that could have been avoided if patients were operated by surgeons that have completed the learning curve). This article provides an overview of the evidence of the impact of learning curves after implementation of MIE. In addition, caveats for implementation and available evidence regarding factors that are important for safe implementation and safe pioneering of MIE are discussed.
基金Supported by National Natural Science Foundation of China,No.U1713221.
文摘BACKGROUND In robot-assisted(RA)spine surgery,the relationship between the surgical outcome and the learning curve remains to be evaluated.AIM To analyze the learning curve of RA pedicle screw fixation(PSF)through fitting the operation time curve based on the cumulative summation method.METHODS RA PSFs that were initially completed by two surgeons at the Beijing Jishuitan Hospital from July 2016 to March 2019 were analyzed retrospectively.Based on the cumulative sum of the operation time,the learning curves of the two surgeons were drawn and fit to polynomial curves.The learning curve was divided into the early and late stages according to the shape of the fitted curve.The operation time and screw accuracy were compared between the stages.RESULTS The turning point of the learning curves from Surgeons A and B appeared in the 18th and 17th cases,respectively.The operation time[150(128,188)min vs 120(105,150)min,P=0.002]and the screw accuracy(87.50%vs 96.30%,P=0.026)of RA surgeries performed by Surgeon A were significantly improved after he completed 18 cases.In the case of Surgeon B,the operation time(177.35±28.18 min vs 150.00±34.64 min,P=0.024)was significantly reduced,and the screw accuracy(91.18%vs 96.15%,P=0.475)was slightly improved after the surgeon completed 17 RA surgeries.CONCLUSION After completing 17 to 18 cases of RA PSFs,surgeons can pass the learning phase of RA technology.The operation time is reduced afterward,and the screw accuracy shows a trend of improvement.
文摘This study was performed to investigate the learning curve of transurethral enucleation with bipolar energy(TUEB)for benignprostatic hyperplasia.The study involved 494 consecutive patients who underwent TUEB for benign prostatic hyperplasia fromAugust 2018 to March 2022 by one surgeon(SJJ,Seoul National University Bundang Hospital,Seongnam,Korea).The patientswere followed up at 1 week,1 month,3 months,and 6 months postoperatively.To evaluate the learning curve of TUEB,perioperativeparameters including the enucleation ratio(enucleated tissue weight/transitional zone volume),TUEB efficiency(enucleatedtissue weight/operation time),and enucleation efficiency(enucleated tissue weight/enucleation time)were analyzed.Functionaloutcomes and postoperative complications were also assessed,including the International Prostate Symptom Score(IPSS),IPSSquality-of-life(QoL)score,and uroflowmetry outcomes.The patients’median age was 72(interquartile range[IQR]:66–78)years,and the estimated prostate volume and transitional zone volume were 63.0(IQR:46.0–90.6)ml and 37.1(IQR:24.0–60.0)ml,respectively.The enucleation ratio,TUEB efficiency,and enucleation efficiency were 0.60(IQR:0.46–0.54)g ml−1,0.33(IQR:0.22–0.46)g min−1,and 0.50(IQR:0.35–0.72)g min−1,respectively,plateauing after 70 cases.The functional outcomes,including total IPSS,IPSS QoL score,and uroflowmetry outcomes,significantly improved at 6 months after TUEB(all P<0.05),but without significant differences over the learning curve.Sixty-five(13.2%)patients developed complications after TUEB,21.5%of whom experienced major complications(Clavien–Dindo grade≥3).The rate of major complications declined as the number ofTUEB cases increased(P=0.013).Our results suggest that the efficiency of TUEB stabilized within 70 procedures.
文摘Deep neural networks are gaining importance and popularity in applications and services.Due to the enormous number of learnable parameters and datasets,the training of neural networks is computationally costly.Parallel and distributed computation-based strategies are used to accelerate this training process.Generative Adversarial Networks(GAN)are a recent technological achievement in deep learning.These generative models are computationally expensive because a GAN consists of two neural networks and trains on enormous datasets.Typically,a GAN is trained on a single server.Conventional deep learning accelerator designs are challenged by the unique properties of GAN,like the enormous computation stages with non-traditional convolution layers.This work addresses the issue of distributing GANs so that they can train on datasets distributed over many TPUs(Tensor Processing Unit).Distributed learning training accelerates the learning process and decreases computation time.In this paper,the Generative Adversarial Network is accelerated using the distributed multi-core TPU in distributed data-parallel synchronous model.For adequate acceleration of the GAN network,the data parallel SGD(Stochastic Gradient Descent)model is implemented in multi-core TPU using distributed TensorFlow with mixed precision,bfloat16,and XLA(Accelerated Linear Algebra).The study was conducted on the MNIST dataset for varying batch sizes from 64 to 512 for 30 epochs in distributed SGD in TPU v3 with 128×128 systolic array.An extensive batch technique is implemented in bfloat16 to decrease the storage cost and speed up floating-point computations.The accelerated learning curve for the generator and discriminator network is obtained.The training time was reduced by 79%by varying the batch size from 64 to 512 in multi-core TPU.
基金Supported by the National Natural Science Foundation of China(No.81970808)Natural Science Foundation of Guangdong Province,China(No.2019A1515011196No.2020A1515010121)。
文摘AIM:To explore the learning curve for ophthalmologists at the start of laser peripheral iridectomy(LPI)training.METHODS:The learning curve of 4 doctor groups without previous LPI experience was studied.Three main parameters of LPI were reviewed:total energy,argon energy and neodymium-doped yttrium aluminum garnet(Nd:YAG)energy.Procedures were evaluated in cohorts of 20 cases to identify the turning points of the three variables.RESULTS:There was no significant difference in terms of age or eye among the 4 doctor groups.There were stable trends on the learning curve for the Doctor A and C groups regarding total energy and argon energy.In addition,the turning points on the learning curve were determined after the 20th procedure for the Doctor B and D groups regarding total energy and argon energy.Moreover,the Nd:YAG energy was relatively stable since the first procedure.CONCLUSION:It requires approximately 20 procedures for a beginner to reach a turning point on the learning curve regarding LPI.It can serve as a point of reference or guideline for training beginners to perform LPI.
文摘AIM： To use the cumulative sum analysis score（CUSUM） to construct objectively the learning curve of phacoemulsification competency.METHODS： Three second-year residents and an experienced consultant were monitored for a series of 70 phacoemulsification cases each and had their series analysed by CUSUM regarding posterior capsule rupture（PCR） and best-corrected visual acuity. The acceptable rate for PCR was 〈5%（lower limit h） and the unacceptable rate was 〉10%（upper limit h）. The acceptable rate for bestcorrected visual acuity worse than 20/40 was 〈10%（lower limit h） and the unacceptable rate was 〉20%（upper limit h）. The area between lower limit h and upper limit h is called the decision interval. RESULTS： There was no statistically significant difference in the mean age, sex or cataract grades between groups. The first trainee achieved PCR CUSUM competency at his 22 nd case. His best-corrected visual acuity CUSUM was in the decision interval from his third case and stayed there until the end, never reaching competency. The second trainee achieved PCR CUSUM competency at his 39^ th case. He could reach best-corrected visual acuity CUSUM competency at his 22 ^nd case. The third trainee achieved PCR CUSUM competency at his 41 st case. He reached bestcorrected visual acuity CUSUM competency at his 14 ^th case.CONCLUSION： The learning curve of competency in phacoemulsification is constructed by CUSUM and in average took 38 cases for each trainee to achieve it.
基金This study was carried out without any commercial sponsorship from equipment manufacturers.
文摘To estimate the short-term results of robot-assisted laparoscopic radical prostatectomy(RALRP)during the learning curve,in terms of surgical,oncological and functional outcomes,we conducted a prospective survey on RALRP.From July 2007,a single surgeon performed 63 robotic prostatectomies using the same operative technique.Perioperative data,including pathological and early functional results of the patient,were collected prospectively and analyzed.Along with the accumulation of the cases,the total operative time,setup time,console time and blood loss were significantly decreased.No major complication was present in any patient.Transfusion was needed in six patients;all of them were within the initial 15 cases.The positive surgical margin rate was 9.8%(5/51)in pT2 disease.The most frequent location of positive margin in this stage was the lateral aspect(60%),but in pT3 disease multiple margins were the most frequent(41.7%).Overall,53(84.1%)patients had totally continent status and the median time to continence was 6.56 weeks.Among 17 patients who maintained preoperative sexual activity(Sexual Health Inventory for Men≥17),stage below pT2,followed up for>6 months with minimally one side of neurovascular bundle preservation procedure,12(70.6%)were capable of intercourse postoperatively,and the mean time for sexual intercourse after operation was 5.7 months.In this series,robotic prostatectomy was a feasible and reproducible technique,with a short learning curve and low perioperative complication rate.Even during the initial phase of the learning curve,satisfactory results were obtained with regard to functional and oncological outcome.
基金Supported by Dana Center for Preventative Ophthalmology,Wilmer Eye Institute,Johns Hopkins University School of Medicine,Baltimore,Maryland 21287Johns Hopkins School of Medicine Dean’s Summer Research Funding,Johns Hopkins University School of Medicine,Baltimore,Maryland 21205-2196。
文摘AIM: To identify instrument holding archetypes used by experienced surgeons in order to develop a universal language and set of validated techniques that can be utilized in manual small incision cataract surgery(MSICS) curricula. METHODS: Experienced cataract surgeons performed five MSICS steps(scleral incision, scleral tunnel, side port, corneal tunnel, and capsulorhexis) in a wet lab to record surgeon hand positions. Images and videos were taken during each step to identify validated hand position archetypes.RESULTS: For each MSICS step, one or two major archetypes and key modifying variables were observed, including tripod for scleral incision, tripod-thumb bottom for scleral tunnel, underhand-index to thumb grip for side port, index-contact tripod for corneal entry, and tripodforceps for capsulorhexis. Key differences were noted in thumb placement and number of fingers supporting the instrument, and modifying variables included index finger curvature and amount of flexion.CONCLUSION: Identification of optimal hand positions and development of a formal nomenclature has the potential to help trainees adopt hand positions in an informed manner, influence instrument design, and improve surgical outcomes.
基金Supported by Shanxi Provincial Science and Technology Department Social Development Fund,No.201903D321144.
文摘BACKGROUND Robotic pancreaticoduodenectomy(RPD)can achieve similar surgical results to open and PD;however,RPD has a long learning curve and operation time(OT).To address this issue,we have summarized a surgical path to shorten the surgical learning curve and OT.AIM To investigate the effective learning curve of a“G”-shaped surgical approach in RPD for patients.METHODS A total of 60 patients,who received“G”-shaped RPD(GRPD)by a single surgeon in the First Hospital of Shanxi Medical University from May 2017 to April 2020,were included in this study.The OT,demographic data,intraoperative blood loss,complications,hospitalization time,and pathological results were recorded,and the cumulative sum(CUSUM)analysis was performed to evaluate the learning curve for GRPD.RESULTS According to the CUSUM analysis,the learning curve for GRPD was grouped into two phases:The early and late phases.The OT was 480±81.65 min vs 331±76.54 min,hospitalization time was 22±4.53 d vs 17±6.08 d,and blood loss was 308±54.78 mL vs 169.2±35.33 mL in the respective groups.Complications,including pancreatic fistula,bile leakage,reoperation rate,postoperative death,and delayed gastric emptying,were significantly decreased after this surgical technique.CONCLUSION GRPD can improve the learning curve and operative time,providing a new method for shortening the RPD learning curve.
文摘The learning curve in minimally invasive colorectal surgery is a constant subject of discussion in the literature.Discordant data likely reflects the varying degrees of each surgeon’s experience in colorectal,laparoscopic or robotic surgery.Several factors are necessary for a successful minimally invasive colorectal surgery training program,including:Compliance with oncological outcomes;dissection along the embryological planes;constant presence of an expert tutor;periodic discussion of the morbidity and mortality rate;and creation of a dedicated,expert team.
文摘Background: Rhinoplasty is a complex surgical procedure that requires critical analysis and precise design before surgery, making it a challenging operation for both the surgical team and medical educators. This study aimed to evaluate the impact of 3D design involvement on learning curves and to establish a more effective method for rhinoplasty education.Methods: Surgeons who participated in an educational program were divided into two groups. The experimental group was involved in the 3D design before the operation, and the control group was asked to review the rhinoplasty atlas. A self-assessment questionnaire was used to evaluate the learning curve of the eight rhinoplasty procedures for each surgeon, and the overall satisfaction rate data were also collected.Results: The self-assessment scores in both groups showed an increasing trend from the first to the eighth operation. The mean scores of the experimental group were significantly higher than those of the control group at the fifth operation(P=0.01). The satisfaction rate of the experimental group(91.7%) was higher than that of the control group(54.5%).Conclusion: The 3D imaging system can improve the learning curve and satisfaction rate of rhinoplasty education,proving that it is an easy and effective tool for medical education.
文摘Objectives: To summarize the current status and outlook of pancreatic duct drainage in the learning curve period of laparoscopic pancreaticoduodenectomy (LPD). Methods: By searching the literature related to the efficacy analysis of internal versus external pancreatic duct drainage in pancreaticoduodenectomy (OPD) and the learning curve period of laparoscopic pancreaticoduodenectomy in recent years at home and abroad and making a review. Results: Because of the complexity of the LPD surgical procedure, the high technical requirements and the high complication rate, it is necessary for the operator and his/her team to carry out a certain number of cases to pass through the learning curve in order to have a basic mastery of the procedure. In recent years, more and more pancreatic surgeons have begun to promote and use pancreatic duct drains. However, no consensus conclusion has been reached on whether to choose internal or external drainage for pancreatic duct placement and drainage in LPD. Conclusions: Intraoperative application of pancreatic duct drainage reduces the incidence of pancreatic fistula during the learning curve of laparoscopic pancreaticoduodenectomy. However, external pancreatic duct drainage and internal pancreatic duct drainage have both advantages and disadvantages, so when choosing the drainage method, one should choose the appropriate drainage method in conjunction with one’s own conditions, so as to reduce the incidence of complications.
基金supported by the National Key Research and Development Program of China(Grant No.2021YFC2501101 and 2020YFC2004701 to XC)Natural Science Foundation of China(Grant no.82202244 to YC)Top Talent Support Program for Medical Experts Team of Wuxi Health Committee(Grant No.202109 to SW).
文摘Objective Single-stage surgery combining embolisation and microsurgery has been increasingly used as a stand-alone procedure to cure complex AVMs.This study aimed to investigate the learning curve and embolisation strategy for single-stage surgery for AVMs.Methods This prospective cohort study used data from the nationwide Multimodality Treatment for Brain Arteriovenous Malformations(MATCH)registry in China,conducted between August 2011 and December 2023.A total of 213 complex AVMs were divided into two groups.Group 1 included the first 25 patients.The 188 cases in group 2 included patients numbered 26-213.A case-crossover design was employed to evaluate the influence of complications,unfavourable outcomes and worsening modified Rankin Scale(mRS)score.Cumulative summation analysis was performed to assess the learning curve.Results The rate of major complications decreased from 52.00%in group 1 to 34.57%in group 2(p=0.089),while the rate of unfavourable outcomes decreased from 44.00%in group 1 to 18.62%in group 2(p=0.004).The distribution of the three preoperative embolisation strategies was as follows:curative:72.00%and 19.15%,palliative:24.00%and 67.55%,and targeted:4.00%and 13.30%,respectively(p<0.001).Multivariable regression analysis showed that surgeon experience was associated with a lower rate of unfavourable outcomes(p=0.022,OR=0.333).The mean follow-up duration was 49.90±20.54 months.The follow-up mRS score of 5-6 decreased from 9.09%in group 1 to 0.8%in group 2(p=0.035).Conclusions Performing single-stage combined surgery in 25 AVM cases is necessary to achieve reproducibility.Rates of major complications and unfavourable outcomes decreased significantly after the first 50 procedures.Palliative and targeted embolisation strategies are associated with a lower rate of unfavourable outcomes.
文摘Background:Pancreatoduodenectomy(PD)is a major surgical procedure that is still mostly performed via open approach[open PD(OPD)]since the laparoscopic approach(LA)is limited outside specialised centers.Robot-assisted PD(RPD)appears to decrease the difficulties associated with LA.However,previously published studies are partly biased because they stem from institutions with extensive access to robotic platforms(ARPs).The present study aims to analyse the safety of RPD compared with OPD and the specific learning curve when performed with limited ARP.Methods:This prospective single-center study was conducted in a high-volume pancreatic surgery center but with limited ARP between May 2018 and October 2023.Safety(primary endpoint:90-day mortality)was assessed using propensity score matching(2:1)to compare RPD and OPD.The learning curve was evaluated using cumulative sum(CUSUM)control chart analysis(split into three consecutive periods of 20 patients),focusing on operative time and complications.Results:A total of 354 PD were analysed,of which 60(17%)were RPD.A matched cohort of 120 OPD was used for comparison.The conversion rate was 15%in the RPD group.The 90-day mortality rate was 5%and 8.3%for RPD and OPD,respectively(P=0.55).The RPD learning curve showed a reduction in hospital stay(19.9 vs.25.3 vs.14.5 days,P=0.17)and a decrease in post-operative complications with increasing experience.Conclusions:Even with limited ARP,setting up a robotic program for PD is feasible and safe but it requires a learning curve of 40 patients.During this initial phase,careful patient selection is mandatory.
文摘Background Microendoscopic discectomy （MED） is a minimally invasive operation that allows rapid recovery from surgery for lumbar disc herniation, but has replaced traditional open surgery in few hospitals because most surgeons avoid its long learning curve. We evaluated the effectiveness and safety of lumbar MED at stages of spinal surgeons＇ learning curve. Methods Fifty patients receiving MED from June 2002 to February 2003 were divided into chronological groups of ten each： A-E. The control group F was ten MED patients treated later by the same medical team （September-October 2006）. All operations were performed by the same team of spinal surgeons with no MED experience before June 2002. We compared groups by operation time, blood loss, complications and need for open surgery after MED failure. Results Operation times by group were： A, （107±14） minutes; B, （85±13） minutes; C, （55±19） minutes; D, （52±12） minutes; E, （51±13） minutes; and F, （49±15） minutes. Blood loss were： A, （131±73） ml; B, （75±20） ml; C, （48±16） ml; D, （44±17） ml; E, （45±18） ml; and F, （45±16） ml. Both operation time and blood loss in groups C, D, E and F were smaller and more stable compared with groups A and B. Japanese Orthopedic Association assessment （JOA） score of each group in improvement rate immediately and one year after operation were as follows （in percentage）： A, （79.8±8.8）/（89.8±7.7）; B, （78.6±8.5）/（88.5±7.8）; C, （80.8±11.3）/（90.8±6.7）; D, （77.7±11.4）/（88.9±9.3）; E, （84.0±8.7）/（89.6±9.0）; and F, （77.8±11.6）/ （86.9±8.4）. Groups showed no statistical difference in improvement rates. Complications developed in three patients in group A, two in group B, and none in the other groups. Conclusions Spinal surgeons performing MED become proficient after 10-20 operations, when their skill becomes fairly sophisticated. Patients＇ improvement rate is the same regardless of surgeons＇ phase of learning curve.
文摘Background Spine surgery using computer-assisted navigation （CAN） has been proven to result in low screw misplacement rates, low incidence of radiation exposure and excellent operative field viewing versus the conventional intraoperative image intensifier （CⅢ）. However, as we know, few previous studies have described the learning curve of CAN in spine surgery.Methods We performed two consecutive case cohort studies on pedicel screw accuracy and operative time of two spine surgeons with different experience backgrounds, A and B, in one institution during the same period. Lumbar pedicel screw cortical perforation rate and operative time of the same kind of operation using CAN were analyzed and compared using CⅢ for the two surgeons at initial, 6 months and 12 months of CAN usage.Results CAN spine surgery had an overall lower cortical perforation rate and less mean operative time compared with CⅢ for both surgeon A and B cohorts when total cases of four years were included. It missed being statistically significant,with 3.3% versus 4.7% （P=0.191） and 125.7 versus 132.3 minutes （P=0.428） for surgeon A and 3.6% versus 6.4%（P=0.058）, and 183.2 versus 213.2 minutes （P=0.070） for surgeon B. in an attempt to demonstrate the learning curve,the cases after 6 months of the CAN system in each surgeon＇s cohort were compared. The perforation rate decreased by 2.4% （P=0.039） and 4.3% （P=0.003） and the operative time was reduced by 31.8 minutes （P=0.002） and 14.4 minutes （P=0.026） for the CAN groups of surgeons A and B, respectively. When only the cases performed after 12 months using the CAN system were considered, the perforation rate decreased by 3.9% （P=0.006） and 5.6% （P 〈0.001） and the operative time was reduced by 20.9 minutes （P 〈0.001） and 40.3 minutes （P 〈0.001） for the CAN groups of surgeon A and B, respectively.Conclusions In the long run, CAN spine surgery decreased the lumbar screw cortical perforation rate and operative time. The learning curve showed a sharp drop after 6 months of using CAN that plateaued after 12 months; which was demonstrated by both perforation rate and operative time data. Careful analysis of the data showed CAN is especially useful for less experienced surgeon to reduce perforation rate and intraoperative time, although further comparative studies are anticipated.
