lntraoperative complication rates in cataract surgery performed by resident trainees and staff surgeons in a tertiary eyecare center in Hungary

INTRODUCTION

Altogether, 2379 (72.7%), 816 (25.0%), and 77 (2.3%)surgeries involved topical, retrobulbar, and general anesthesia,respectively. Trypan blue dye staining of the anterior capsule was performed in 120 (3.7%) cases and iris hooks were used in 92 (2.8%) cases. Specialists (=573, 96.0%) performed significantly more complex cataract surgeries (＜0.001) than residents (=24, 4.0%).

The study was conducted at a tertiary eyecare center in Hungary. The study was approved by the Regional and Institutional Committee of Science and Research Ethics of Semmelweis University, Hungary (No.121/2021).The study was performed in accordance with the Declaration of Helsinki Guidelines for Human Research. Written informed consent was obtained from the patients.

SUBJECTS AND METHODS

Although residency programs should provide trainees with the opportunity to improve their surgical skills, patient safety is always the most important aspect of the procedure. This duality poses a great dilemma in residency training programs.Phaco surgery is a single-surgeon operation, during which the specialist can supervise, leading the resident through the surgery verbally, and in case of intraoperative difficulty or complication, possibly take over and finish the surgery to ensure patient safety. Phaco surgery is a highly complex procedure with well-differentiated unique steps. Several studies have attempted to determine the difficult stages of phaco surgery for residents, albeit subjectively. However,to our knowledge, no study has objectively analyzed this issue.The primary aim of this study was to determine the incidence and types of intraoperative complications in phaco surgery in a tertiary eyecare center in Hungary and to compare these complications between residents and specialists. The secondary aim was to objectively assess the order of difficulty of phaco surgery steps for residents.

目前大部分船东选择观望态度。近期，德鲁里航运咨询公司（Drewry）对船东做了一个调查，调查数据显示，现有船东66%选择低硫燃油，13%选择安装脱硫装置，8%选择使用液化天然气，13%选择其他方式。普氏等机构也预测，未来几年使用低硫燃油、加装废气清洁系统将会被多数航运公司选择，以液化天然气为动力则是远期趋势。

分别取3组肝微粒体代谢样品进样，得GC/MS谱图，分别列于图1。对鱼腥草注射液及新鱼腥草素钠注射剂肝微粒代谢产物进行分析得：鱼腥草注射液的肝微粒样品中共测出126种产物，而新鱼腥草素钠注射剂样品中共测出99种产物，空白样品测出121种产物，扣除与空白相同的产物，得鱼腥草注射液肝微粒代谢产物为20个，新鱼腥草素钠注射剂肝微粒代谢产物为24个。其化学名和结构见表1、2。

The study included 3272 consecutive cases. There were 1261 (38.5%) men and 2011 (61.5%) women in the study population. The mean patient age was 69.8±11.1y (range,17mo-98y). Of these patients, 1659 (50.7%) underwent surgery on the right eye and 1613 (49.3%) underwent surgery on the left eye. There were 3158 (96.5%) corticonuclear, 80 (2.5%)mature, 22 posterior polar (0.7%), 8 (0.2%) traumatic, and 4 hypermature (0.1%) cataract cases.

资源库是以服务学校教学为主，资源库服务的主要对象是学生和老师。老师怎么用方便、学生需要什么是资源库建设过程中需要考虑的主要内容，资源的合理规划和建设质量决定着老师和学生使用是否方便有效，进而影响资源库的推广与应用，因此资源的规划与建设至关重要。常州工程职业技术学院为职业教育焊接技术及自动化专业教学资源库牵头单位，承担了4门核心课程和2个培训包的建设，本文就以作者承担的《非熔化极气体保护焊》课程为例，探讨资源库整体规划和建设。

Phaco surgery is a cornerstone of the residency training worldwide. While only 7.3% of all phaco surgeries involved residents in Hungary, studies from other industrialized countries reported much higher resident involvement rates(21%-64%). Our institution is the biggest and leading ophthalmic center in Hungary, and about 4 new residents begin their residency training every year in the clinic. The ophthalmology residency lasts for 5y and phaco surgery training begins in the second year. During the entire residency training, every resident performs 50 to 150 phaco surgeries at our institution, and this number may be associated with the lesser surgical experience compared to that in Canada, United Kingdom and Portugal where every resident performs 320 to 400 phaco surgeries on average during the same period.To ensure patient safety, specialists are allowed to swap the operating position with the resident during the surgery, in case of intraoperative complication or before predictable complication(s).

Statistical analysis was performed with statistica 8.0 (StatSoft Inc., Tulsa, OK, US). Data are expressed as the mean±standard deviation (SD). The Chi-square test was used to analyze the differences in the proportions of categorical variables.＜0.05 was considered statistically significant.

RESULTS

This retrospective review included 3272 consecutive patients who underwent primary phaco surgery performed by residents and specialists over a period of 1y, from January 1, 2019, to December 31, 2019, at the Department of Ophthalmology,Semmelweis University, Budapest, Hungary. For each subject,the clinical data were reviewed, which included patient demographics (sex, age, and eye laterality), clinical history(earlier intraocular surgeries), preoperative and postoperative ophthalmological status (case complexity), and operative details (usage of trypan blue dye staining, iris hooks, and intraoperative complications).

分布式光纤测温系统在LNG储罐中的工程化应用及国产化推广……………………………………………………… 操伟中（7-82）

Of the surgeries, 3031 (92.6%) were completed by specialists alone and 241 (7.4%) were performed by residents or byresidents and specialists.

There were 2675 (81.8%) simple and 597 (18.2%) complex cataract surgeries. The most common complexities (Table 1)were patients with earlier vitrectomy (=156, 4.8%), high axial myopia (=114, 3.5%), corneal scar, corneal dystrophy or keratoconus (=107, 3.3%), narrow angles (n=74, 2.3%),pseudoexfoliation or zonular fiber compromise (=53, 1.6%),and small pupil or intraoperative floppy-iris syndrome (=50,1.5%).

Cataract surgery is one of the most commonly performed ophthalmic surgeries worldwide. Thus, learning to perform cataract surgery with phacoemulsification (phaco surgery) is an essential part of ophthalmology training programs. Because of the increasing availability of surgical devices and technical advancement, complication rates are decreasing. However, intraoperative complication rates may differ between staff surgeons (specialists) and resident trainees(residents). Only a few large-scale studies have compared intraoperative complication rates between specialists and residents, and differences between these studies may be due to different structures in residency trainings. Thus, it is important to gain insight from different countries with different education systems to develop more effective training methods.

月在水中上上下下，风又瑟瑟地走过去，波上起了粼粼的纹理，光影如梦，波痕是诗，风月水三者一聚首，很妙的天趣。

The intraoperative complication rate was significantly higher(＜0.001) among residents (=33, 13.7%) than among specialists(=144, 4.8%). The complication rate in simple cases was 5.3% (=127), with intraoperative complication rates being significantly more common (＜0.001) in residents (=29,13.4%) than in specialists (=98, 4.0%; Table 3).

The complication rate in complex cases was 8.4% (=50) and was not significantly different (=0.13) between residents(=4, 16.7%) and specialists (=46, 8.0%). The most common intraoperative complications were posterior capsule tear (PCT;=85, 2.6%), PCT with vitreous loss (=54, 1.65%), anterior capsule tear (ACT;=50, 1.53%), and zonular fiber loss (=45,1.38%) in the whole study population. Anterior vitrectomy was performed in 58 (1.8%) cases and pars plana vitrectomy in 21(0.6%) cases.

Among 241 surgeries performed by residents, 110 were completed with the involvement of a specialist (Figure 1).

The replacement of residents by specialists during phaco surgery occurred during phaco in 66 (60.0%), capsulorhexis in 21 (19.1%), irrigation/aspiration in 13 (11.8%), hydrodissection in 9 (8.2%), and IOL implantation in 1 case (0.9%).

The overall intraoperative complication rate was 5.4% (=177;Table 2).

Anterior vitrectomy and pars plana vitrectomy were more frequently (＜0.001) among resident cases (=12, 5.0% and=6, 2.5%, respectively) than in specialist cases (=46, 1.5%and=15, 0.5%, respectively).

In the whole study population, IOL was implanted in the capsular bag in 3169 (96.9%) and in the ciliary sulcus in 62(1.9%) persons. Iris-claw IOL was fixed on the iris in 9 cases(0.3%), and 32 patients (0.9%) were left aphakic after the primary surgery. Significantly more patients (＜0.01) were left aphakic after the primary surgery performed by residents (=7,2.9%) when compared to primary surgery by specialists (=25,0.8%).

DISCUSSION

Cataract is a leading cause of visual impairment and phaco surgery is the most frequently performed intraocular surgery worldwide. Almost 4.2 million phaco procedures were performed in Europe in 2015.

钉钉群的建立为以班级为单位的学生工作单元搭建了平台。通过该群发布的信息，能够明确显示已读与未读情况，进而实现了信息公告知晓度的动态监控。对于尚未及时读取公告的同学，钉钉软件设置了“钉”功能，可以选取电话、信息、应用内提醒等方式对该同学进行提醒。以此确保每一位同学都能接受到公告信息。

Cataract is usually an unavoidable side effect of aging.Nearly one-third of people aged 65 years and over have visually significant cataract in Europe. Phaco surgery is a relatively safe routine procedure with a low complication rate. However, complications do occur and can cause severe visual impairment.

We analyzed the intraoperative complication rates for phaco surgery performed by specialists and residents and objectively determined the difficulty of each stage of the surgery at a tertiary eyecare center in Hungary. To the best of our knowledge, this is the first study to objectively report the order of difficulty in phaco surgery steps for residents. This is also the first study to report on intraoperative complication rates for primary phaco surgery, comparing specialists and residents in Hungary.

人力资本积累影响制造业结构升级的实证研究....................................................................................................阳立高 李永奇 韩 峰 龚世豪（1）

The overall intraoperative complication rate was 5.4% and was higher than that reported by other studies in Sweden (0.9%),Canada (1.8%), Portugal (4.1%), and Australia (4.9%).Intraoperative complication rates for residents in this study was much higher (13.7%) compared to that reported by Lowin Canada (2.7%), Brisziin Germany (3.8%),Fongin Australia (6.1%), Oliveira-Ferreirain Portugal (6.3%), and Ellisin the USA (7.8%).Further, complication rates during phaco surgeries performed by specialists alone in Hungary (4.8%) were slightly higher compared to that reported in Australia (2.7%)and Portugal(3.3%). Comparisons of intraoperative complication rates between residents and specialists showed different results in different countries. While Lowand Fongdid not find a significant difference between the two groups, our study and that of Oliveira-Ferreirafound significantly higher complication rates among residents during phaco surgery.Differences may be explained by the different numbers of phaco surgeries performed by residents during the residency program in different countries, because increased resident experience seems to decrease the incidence of intraoperative complications.

The factors contributing to the replacement of residents by specialists during phaco surgery were noted to objectively analyze which surgical steps were the most challenging for residents. Thirty-one specialists and 9 residents performed the phaco surgeries. One resident was in the second, 3 in the third, 3 in the fourth, and 2 in the fifth year of the residency.All surgeries included clear corneal incisions, continuous curvilinear capsulorhexis, and hydrodissection. Phaco techniques were performed in descending order as follows:phaco-crack (=1338, 40.9%), stop-and-chop (=780, 23.8%),phaco-chop (=659, 20.1%), divide-and-conquer (=436,13.3%), and unclassifiable (=59, 1.8%).

In the present study, the order and incidence of the most notable intraoperative complications were similar to findings from other studies as follows: PCT (2.6%), ACT (1.53%),zonular fiber loss (1.38%), and dropped nucleus (0.4%). The incidence of PCT (2.3%) and that of dropped nucleus among specialists (0.3%) were also similar to data from Canada and Portugal. The incidence of ACT (5.81%) and PCT (6.22%)in residents was higher in our sample compared to that reported by Oliveira-Ferreirafrom Portugal (ACT: 1.0%; PCT:3.4%), Corey and Olsonand Bhagatfrom the USA(PCT: 2.0% and 6.7%), and Lowfrom Canada (PCT:0.8%). Dropped nucleus occurred also more frequently among residents in Hungary (2.0%) than in Germany (1.2%), Portugal(0.6%), and in the USA (0.6%). PCT and vitrectomy due to dropped nucleus are considered as a benchmark intraoperative complication, because they are associated with a higher incidence of postoperative endophthalmitis (8×) and retinal detachment (42×).

The intraoperative complication rate also depends on case complexity. Al-Jindanreported that the complication rate may be twofold in complex cases, compared to that in simplex cases. To reduce the effect of complex cases on complication rates, we also analyzed the intraoperative complication rates in simple cases. The incidence rates showed similar values across the entire sample and compared to other studies with one exception, where the incidence of PCT among residents also showed a higher value (6.9%) as in the whole sample.

The most difficult steps of the phaco surgery, where the specialist took over the operation from the resident, were phaco(60.0%), capsulorhexis (19.1%), irrigation/aspiration (11.8%),and hydrodissection (8.2%). The difficulty of each stage of phaco surgery is of great interest. Knowing which part of the surgery poses the greatest complexity for residents would be useful to design training methods alongside to enhance the practice of those critical steps. Several authors subjectively evaluated the difficulty of each stage of phaco surgery among residents. Based on their results and similar to our results,residents found phaco, capsulorhexis, and irrigation/aspiration to be the most challenging parts of the surgery. Based on the subjective and objective assessment of phaco surgery difficulties and the incidence of different complication rates among residents, phaco and capsulorhexis may be considered the most challenging steps in phaco surgery for residents.

In our curriculum, the number of phaco surgeries performed by residents during the 5y of residency is lower compared to published data from other developed countries. This is because our department places emphasis on theoretical knowledge prior to surgical skill in the first part of the training, after which the resident begins to perform a higher number of surgeries.This difference in the curriculum explains the disparity in the number of surgeries performed by specialists and residents.

The limitations of our study include its retrospective design, its involvement of only a single center, and the non-randomization of patients.

In conclusion, intraoperative complication rates were higher in residents than in specialists. Resident involvement into phaco surgery should be increased in our department in Hungary, in order to improve surgical confidence and acquire safe phaco techniques until the end of the residency. Objective assessment of difficulty stages in phaco surgery was in line with the subjective measurement of difficulty levels reported by other surveys, with the most challenging parts of phaco surgery being phaco and capsulorhexis.

众人嘻嘻的笑着，从衣角里，老头子依稀看得出场面上一圈观众的腿脚，他便替王九用真脚绊倒了赵四的假脚，傀儡与藏在衣下玩傀儡的，一齐颓然倒在灰土里，场面上起了哄然的笑声，玩意儿也就作了小小结束了。

Magyar M conducted the survey,analyzed the data, and wrote the article. Sándor GL and Ujváry L conducted the survey and analyzed the data. Nagy ZZ planned the survey and reviewed the manuscript. Tóth G designed the survey, and edited and reviewed the manuscript.

None;None;None;None;None.