대한안과학회지 2019 년제 60 권제 7 호 J Korean Ophthalmol Soc 2019;60(7):654-660 ISSN 0378-6471 (Print) ISSN 2092-9374 (Online) https://doi.org/10.3341/jkos.2019.60.7.654 Original Article 초심자안과전문의가시행한수정체유화술중발생한후낭파열빈도 : 현미경조명과안구내조명 Comparison of Posterior Capsule Rupture Rate during Phacoemulsification by Novice Ophthalmologists: Microscope vs. Intracameral Illumination 김유정 1 서혜진 2 이종환 1 김성우 3 정태영 4 이성진 5 박규형 6 남동흔 1 Yu Jeong Kim, MD 1, Hyejin Seo, MD 2, Jong Hwan Lee, MD 1, Seong-Woo Kim, MD, PhD 3, Tae-Young Chung, MD, PhD 4, Sung Jin Lee, MD, PhD 5, Kyu Hyung Park, MD, PhD 6, Dong Heun Nam, MD, PhD 1 가천대학교길병원안과학교실 1, DMC 조은안과 2, 고려대학교구로병원안과학교실 3, 성균관대학교의과대학삼성서울병원안과학교실 4, 순천향대학교서울병원안과학교실 5, 서울대학교분당서울대학교병원안과학교실 6 Department of Ophthalmology, Gachon University Gil Hospital 1, Incheon, Korea DMC Good Eye Clinic 2, Seoul, Korea Department of Ophthalmology, Korea University Guro Hospital 3, Seoul, Korea Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine 4, Seoul, Korea Department of Ophthalmology, Soonchunhyang University Seoul Hospital 5, Seoul, Korea Department of Ophthalmology, Seoul National University Bundang Hospital 6, Seongnam, Korea Purpose: We compared the posterior capsule rupture (PCR) rate between microscope versus intracameral illumination in phacoemulsification surgery performed by novice ophthalmologists. Methods: We conducted a retrospective chart review of 300 eyes of 211 patients who underwent phacoemulsification by novice ophthalmologists from March 2012 to October 2017. Novice ophthalmologists (n = 6) were divided into those using microscope illumination (n = 4) and intracameral illumination users (n = 2). The first 50 cataract surgery cases of each novice ophthalmologist were reviewed. The results using a phacoemulsification machine and microscopy were the same. The intraoperative complications and learning curve in each case were evaluated. Results: Phacoemulsifications performed by novice ophthalmologists showed a statistically significant difference in PCR rate between the microscope illumination (19.0%, 38/200) and intracameral illumination (4.0%, 4/100) groups (p = 0.001). The incidence of PCR was reduced to 22%, 18%, 16%, 12%, and 8% per 10 cases in the microscope group, while it was 15% in the first 10 cases and 0% in 50 cases thereafter in the intracameral illumination group. Conclusions: Novice surgeons had a lower PCR rate during cataract surgery using intracameral illumination than using microscope illumination. Both groups showed a tendency for the PCR to decrease with increasing surgical cases, but the intracameral illumination group showed a shorter learning curve. J Korean Ophthalmol Soc 2019;60(7):654-660 Keywords: Intracameral illumination, Learning curve, Novice ophthalmologist, Phacoemulsification, Posterior capsule rupture Received: 2018. 12. 27. Revised: 2019. 2. 24. Accepted: 2019. 6. 25. Address reprint requests to Dong Heun Nam, MD, PhD Department of Ophthalmology, Gachon University Gil Hospital, #21 Namdong-daero 774beon-gil, Namdong-gu, Incheon 21565, Korea Tel: 82-32-460-3684, Fax: 82-32-460-3358 E-mail: eyedawns@gilhospital.com * Conflicts of Interest: The authors have no conflicts to disclose. 백내장수술은안과의사들에의해가장보편적으로시행되고있는수술중하나로전공의수련중필수적인교육과정이다. 캐나다에서는전체백내장수술의 21-39% 가수련중인안과전공의에의해행해지고있으며, 수련기간동안평균 324개의백내장수술을경험한다고보고하였고, 1,2 미국은평균 80-140개의백내장수술을시행하고있 c2019 The Korean Ophthalmological Society This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. 654
- 김유정외 : 후낭파열 : 현미경조명과안구내조명비교 - 다. 3 하지만국내는 안과전공의수련과정중백내장수술에대한설문조사 에따르면, 수련기간중백내장수술집도횟수가 1-5개인것이대부분이었다. 4 이는국내는국외와달리교육및수련목적의전공의수술에대하여환자들의포용력이적어전공의과정중백내장수술집도의기회가매우낮기때문이며, 더욱이환자들의술후경과에대한기대가높아지고술후발생할수있는합병증에대한이해또한낮아졌기때문으로, 이에따라초심자의백내장수술에서도높은안정성과숙련도가요구되고있다. 하지만숙련도란수술증례수가증가함에따라수술의합병증이감소하고안정성이증가하는학습곡선 (learning curve) 이존재하는것으로처음부터획득하기어려운것이다. 5 백내장수술중발생하는가장심각한술중합병증중하나인후낭파열은낭포황반부종, 망막박리등시력에영향을줄수있는술후합병증이생길수있고, 수술시인공수정체삽입방법에도영향을줄수있다. 일반적으로후낭파열의발생빈도는백내장의종류와정도, 수술방법과수술자의숙련도등에의해영향을받는다. 6 지금까지보고된초음파유화술시후낭파열의빈도는 0.8-17.5% 이고, 이는수술자의경험및숙련도와상관관계를가지는것으로알려져있다. 1-3,6,7 다시말해수술증례수가증가함에따라후낭파열의빈도가감소하는학습곡선 (learning curve) 이존재하는것이다. 4-7 이에따라많은논문에서후낭파열의빈도를백내장수술숙련도의지표로삼고, 학습곡선 (learning curve) 을분석하는것에쓰이고있다. 본연구는본원의백내장수술중후낭파열빈도를파악하던중, 최근 2015년부터 3년간본원의초심자백내장수술에서후낭파열의빈도가급격히감소한것을발견하였고, 2015년부터초심자백내장수술시안구내조명 (intracameral illuminatior) 을사용하는수술의방법적변화라는요인이존재하였다. 따라서이러한안구내조명의사용유무에따른후낭파열의빈도를조사하여그차이를비교하고자하였고, 조명의차이가초심자의백내장수술의숙련도및안정성획득의중요한인자임을확인하고자하였다. 이에본연구에서는동일한수련과정을끝낸초심자전문의가수정체유화술을계획하여단독으로시행한첫 50예의백내장수술에서후낭파열의빈도를안구내조명의사용유무에따라비교하였고, 수술건수별후낭파열빈도를비교하여학습곡선 (learning curve) 을분석해보았다. 대상과방법 저자들은 2012년 3월부터 2017년 10월까지가천대길병원전공의수련과정을마치고전문의를취득한 6명의안 과의사가본대학병원안과학교실에서전임의과정중단독으로수정체유화술을시행했던 300예를대상으로전자의무기록을후향적으로분석하였다. 환자중외상성백내장이거나, 외상성각공막열상, 안구파열등이동반된경우는대상에서제외하였다. 상기연구는인증된연구윤리심의위원회 (Institutional Review Board [IRB]; GCIRB2018-095) 의승인을받았으며헬싱키선언 (Declaration of Helsinki) 을준수하였다. 수술은테논낭하마취또는구후마취를선택적으로행한후연속적원형전낭절개술을시행하고, stop and chop법을이용하여핵분할후초음파유화술을진행되었다. 수술현미경 (M844 C40, Leica Microsystems GmbH, Nussloch, Germany) 및수정체유화술기계 (Whitestar Signature TM Phaco System, Abbott Medical Optics, Maidenhead, UK) 는 6인모두동일하였다. 안구내조명은 Xenon Brightstar (Dutch Ophthalmic Research Center International BV, Zuidland, Netherlands) 의 illuminator을 60% 의밝기로사용하였고, 일반현미경조명은상기모델의 60% 의밝기로사용하였다. 결과 백내장수술은총 6인의초심자전문의에의해서시행되었고현미경조명사용자는 4인, 안구내조명사용자는 2인이었다. 각술자가시행한첫 50예에해당하는수술환자 211명의 300예를현미경조명그룹 (200명) 과안구내조명그룹 (100명) 으로나누어분석하였다. 수술환자의평균연령은현미경조명그룹, 안구내조명그룹각각 73.23 ± 3.39세 (47-86) 와 74.35 ± 4.21세 (45-89) (p=0.425) 였으며, 남 / 여비율은각각 81:119명, 42:58명 (p=0.901), 우안 / 좌안비율은 91:109 명, 49:51명 (p=0.624), 당뇨의비율은 33:35% (p=0.796) 였다. 또한안축장의길이는 23.56:23.57 mm (p=0.959) 였다 (Table 1). 후낭파열은현미경조명그룹에서총 38예에서발생하여 19.0% 의빈도를보였고, 술자별발생률은 18.0-20.0% 였다. 안구내조명그룹에서는총 4예에서발생하여 4.0% 의후낭파열을보였고, 술자별발생률은 2.0%, 6.0% 였다. 이에따라그룹간후낭파열의빈도는통계적으로유의한차이를보였다 (p=0.001) (Table 2). 수술증례수와후낭파열빈도와의관계는수술증례의경험수가증가할수록증례당후낭파열의빈도는점차로감소하는양상을보였다. 이는수술시행건수 10예당후낭파열의수로분석하였고, 현미경조명그룹은첫 10예에서 22%, 이후차례로 18%, 16%, 12%, 8% 로감소하는양상을보였다. 안구내조명그룹은첫 10예에서 15% 를보인후 655
- 대한안과학회지 2019 년제 60 권제 7 호 - Table 1. Patient demographics Factor Microsope illumination (200 cases) Intracameral illumination (100 cases) p-value Age (years) 73.23 ± 3.39 (47-86) 74.35 ± 4.21 (45-89) 0.425 * Sex 0.901 Male 81 (40.5) 42 (42.0) Female 119 (59.5) 58 (58.0) Laterality 0.624 Right 91 (45.5) 49 (49.0) Left 109 (54.5) 51 (51.0) DM 66 (33) 35 (35) 0.796 Axial length (mm) 23.56 23.57 0.959 Values are presented as mean ± standard deviation (range) or number (%). DM = diabetes mellitus. * Independent t-test; chi-square test. Table 2. Posterior capsule rupture of each surgeon PCR Surgeon number Microsope Intracameral illumination illumination p-value * 1 10 (20) 3 (6) 2 9 (18) 1 (2) 3 9 (18) 4 10 (20) Total 38 (19) 4 (4) 0.001 Values are presented as number (%). PCR = posterior capsule rupture. * Chi-square test. 이후 50 예까지 0% 를보였다 (Fig. 1). 고 찰 최근전공의수련기간동안안과의기본수술인백내장수술을직접경험해볼수있는기회가줄어듦에따라술기습득과관련한교육이제대로이루어지지않고있어, 대한안과학회에서도그점을인지하고 Visual Reality Ophthalmic Surgery Simulator (Eyesi Surgical, VRmagic Holding AG, Mannheim, Germany) 을구비하여피교육자에게백내장을포함한안과수술에대한간접경험을제공하여일선교육현장에서부족한부분을보완하기위한시도가있었다. 대한안과학회에서우려하듯수정체유화술은전공의수련과정중반드시교육받아야할기본술기의하나로인식되고있으나 2011년 Eom et al 4 이보고한바에의하면국내전공의수련과정중 48.6% 가 1-5회, 20.0% 가 6-10회정도의집도기회를가지는것으로보고하였다. 이는초심자에있어후낭파열및유리체소실, 유리체강내로의핵소실등의합병증빈도가높은 8 비교적완만한학습곡선을가지는수정체유화술특징을고려하였을때충분한술기습득의기 Figure 1. Phacoemulsification learning curve of each illumination. The incidence of posterior capsule rupture was reduced to 22%, 18%, 16%, 12%, and 8% per 10 cases in the microscope group, while 15% in the first 10 cases and 0% in 40 cases thereafter in the intracameral illumination group. PCR = posterior capsule rupture. 회가되었다보기는힘들다. 이에최근에는많은수에서전공의과정수료후전임의과정에서야비로소백내장수술의학습곡선을경험하게되고, 많은빈도의후낭파열등의합병증을경험하게된다. 6 이전보고에의하면전공의과정중수정체유화술에관련한다수의연구들이있었으나이는국외의연구가대부분이며, 대략 0.8-17.5% 로보고되고있으나의료체계와환자성향, 환자군의특성, 수련체계가다른국내의그것에그대로적용하기는힘들다. 1-3,6,7 국내에도초심자초음파유화술시발생한후낭파열에대해술자 1인의 1,000예경험에대한것과초심자안과전문의 10명의결과가보고되었으나전자는 1,000예의학습곡선이 100예단위로분석되어초기학습곡선을파악하기어렵고, 중간에수술기계나방법의변화가있었다. 6 후자는술자간의수련체계와수술방법의조건및분석된수술건수가동일하지않은비교였다. 7 따라서본연구는초음파유화술을이용한백내장수술의 656
- 김유정외 : 후낭파열 : 현미경조명과안구내조명비교 - Table 3. Comparison of PCR rate Study Total surgeon Total number number of cases PCR Park et al 6 1 100 12 (12.0) Jun and Chang 7 10 412 64 (15.5) Microscope 4 200 38 (19.0) illumination Intracameral illumination 2 100 4 (4.0) Values are presented as number (%). PCR = posterior capsule rupture. A 경험이전무한동일한수련체계와수술방법을가진 6명의초심자의첫 50예의수술결과를정리한것으로, 이는동일한조건의술자를대상으로하였다는점에서기존의논문들과구별되며, 기존의연구에서알수없었던초음파유화술초기의학습곡선 (learning curve) 을그릴수있었다는점에서그의의가있다. 국내의초심자후낭파열의빈도는 Park et al 6 이초심자의첫 1,000예의수정체유화술에서 4.7% 의발생, 초기 100예 B Microscope illumination Intracameral illumination Figure 2. Microscope illumination (A) vs. intracameral illumination (B). In microscope illumination, a red reflex is produced by reflection of bright coaxial light from the macula back to the observer (the ocular of an operating microscope). In Intracameral illumination, on the other hand, a side light of intracameral illumination is shining into not macula but peripheral retina. Therefore, the light reflection from the macula back to the observer is decreased. Furthermore, intracameral illumination improved visibility of the lens and enhanced depth perception of the surgical field. 657
- 대한안과학회지 2019 년제 60 권제 7 호 - 에서는 12% 를보고하였으며, Jun and Chang 7 는 15.5% 의후낭파열을보고하였다 (Table 3). 본연구에서는기존논문과같은조건인현미경조명을사용한증례에선 19% 에서후낭파열이발생하였는데이것은최근의보고들에비해다소높은것이었다. 이는전자는단독수술시행전수정체낭외적출술과공막터널절개방식의수정체유화술을 25예를행한이후의케이스를포함하였고, 후자는상급지도전문의수술중단계별술기학습을다수시행또는상급지도전문의감독아래에수차례집도한수련이후단독으로수정체유화술을시행한케이스를분석하였기때문으로본원의단독수술전백내장수술경험이전무하고, 상급전문의의개입이없는진정한의미의초기수술케이스의특성이반영된것으로생각한다. 또한상대적으로후낭파열의빈도가더높은초기 50예만의발생률을봤기때문으로생각된다. 이런동일조건임을고려할때안내조명을사용한증례에서후낭파열이 4% 에서발생한것은의미있는결과라볼수있다. 수술건수별후낭파열의빈도로분석한학습곡선은현미경조명그룹은첫 10예에서 22%, 이후차례로 18%, 16%, 12%, 8% 로감소하는양상을보였고, 이는기존의보고와같은안과미세수술의완만한학습곡선의특성을보여주며최소 80-100케이스를경험하여야수술의안정성이획득된다는기존연구결과와도상응한다. 5-7 하지만안구내조명그룹은첫 10예에서 15% 를보인후이후 50예까지 0% 를보였으며, 이는후낭파열의급격한감소와함께빠른수술의안정성을획득한것으로해석할수있고, 기존보고에비해빠른학습곡선을보이는결과이다. 이렇게본연구에서안구내조명을사용한케이스는후낭파열의빈도가의미있게낮았으며, 수술의안정성과숙련도가빠르게향상되었다. 저자들은그이유를두그룹의조명차이로인한전체적인수술필드및수정체구조의시인성차이때문으로해석하였다. 안구내조명은본원에서는 2011년부터백내장수술중에도입하여사용하고있는것으로이장치의백내장수술에서의사용은환자및술자의망막에도달하는빛의양을줄여주어광독성 (phototoxicity) 의위험성을감소시킬뿐만아니라, 수정체및수정체낭구조의깊이감, 입체감을향상시켜수술필드의시인성을높여준다 (Fig. 2). 이에성숙백내장, 작은동공, 각막혼탁등이동반된고난이도의백내장에서도안정적인수술을가능하게한다는것을이미여러차례논문을통해발표된바있다. 9-15 높아진시인성은초심자로하여금수정체및후낭의인식을쉽게하였고, 이는미세수술의특징인술자의눈-손간의협응 (hand-eye coordination) 을용이하게하며, 합병증이일어나기전위험사항을쉽게인식하도록해 준다. 그리고명확한수술필드의인식은술중올바른판단및정확한술기를가능하게만든다. 기존의수술훈련프로그램들은돼지의안구를이용하거나 virtual reality training으로가상의수술필드로훈련하는것이라실제수술환경과는차이가있으며, 실질적인수술필드에서의훈련이아니기때문에그효용성및효과에한계가있을수밖에없다. 하지만안구내조명을이용한백내장수술은실제수술필드에서의훈련이기때문에더큰학습효과를보인다고생각한다. 현재는수술에의해발생한합병증을용인받기어려운의료환경이며, 환자는높은술후만족감을당연시하는시대이다. 이런환경에서초심자의수술은술자및병원에큰부담일수밖에없다. 따라서본원의연구결과와같이합병증의발생을감소시킬수있는장치, 수술방법의개발및수술훈련프로그램 (Video watching, Assist, Wet lab, Virtual Reality Training program, Step by Step training 등 ) 의중요성이대두되고있지만현재까지시행되고있는수술훈련프로그램의효율과효과에대한여러연구결과는큰의미를가지는것이없다. 16-20 상기연구는동일한조건을가진술자들의진정한첫 50예의백내장수술결과를분석하여초음파유화술초기의학습곡선 (learning curve) 을그렸다는것, 그리고조명의차이가초심자의백내장수술의숙련도및안정성획득에중요한요인이라는것을제시했다는데에의의가있으나, 후향적연구라는것과비교한두군의술자의수가적었다는점에한계가있다. 따라서향후전향적이며, 많은수의술자를비교한연구가필요할것이다. 결과적으로후낭파열의의미있는감소및효율적인학습효과를보인안구내조명의사용은초심자수술에서합병증의발생을감소시키기위한방법으로의미가있다고하겠다. REFERENCES 1) Low SA, Braga-Mele R, Yan DB, El-Defrawy S. Intraoperative complication rates in cataract surgery performed by ophthalmology resident trainees compared to staff surgeons in a Canadian academic center. J Cataract Refract Surg 2018;44:1344-9. 2) Bhagat N, Nissirios N, Potdevin L, et al. Complications in residentperformed phacoemulsification cataract surgery at new jersey medical school. Br J Ophthalmol 2007;91:13157. 3) Le K, Bursztyn L, Rootman D, Harissi-Dagher M. National survey of Canadian ophthalmology residency education. Can J Ophthalmol 2016;51:219-25. 4) Eom Y, Kang SY, Kim HM, Song JS. A survey report on cataract surgical experiences during ophthalmology residency in Korea. J Korean Ophthalmol Soc 2011;52:429-33. 5) Randleman JB, Wolfe JD, Woodward M, et al. The resident sur- 658
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- 대한안과학회지 2019 년제 60 권제 7 호 - = 국문초록 = 초심자안과전문의가시행한수정체유화술중발생한후낭파열빈도 : 현미경조명과안구내조명 목적 : 초심자안과전문의에의해시행된수정체유화술에서현미경조명사용과안구내조명사용의차이에따른후낭파열의빈도를비교하고자하였다. 대상과방법 : 2012 년 3 월부터 2017 년 10 월까지본원전공의수련과정을마치고전문의를취득한 6 명의안과의사가본대학병원안과학교실에서전임의과정중단독으로수정체유화술을시행했던 300 예, 211 명을대상으로전자의무기록을후향적으로분석하였다. 동일한수련과정을끝낸초심자전문의 6 인중현미경조명사용자 4 명과안구내조명사용자 2 명이었고, 모두같은수정체유화술기계및현미경을사용하였다. 초심자전문의단독으로시행한첫 50 예의백내장수술에서의후낭파열빈도를안구내조명의사용유무에따라비교하였고, 수술건수별후낭파열빈도를비교하여학습곡선 (learning curve) 을분석해보았다. 결과 : 후낭파열은현미경조명그룹에서 19.0% (38/200), 안구내조명그룹에서 4.0% (4/100) 의빈도를보였다 (p=0.001). 수술건수별후낭파열빈도는현미경조명그룹은 10 예당 22%, 18%, 16%, 12%, 8% 로감소하였고, 안구내조명그룹은첫 10 예에서 15% 를보인후이후 50 예까지 0% 를보였다. 결론 : 안구내조명을사용한초심자가현미경조명사용자보다수정체유화술에서더낮은후낭파열빈도를보였다. 학습곡선은수술케이스가증가할수록두그룹모두감소하는양상을보였으나, 안구내조명사용에서더빠르게감소하는것으로나타났다. < 대한안과학회지 2019;60(7):654-660> 김유정 / Yu Jeong Kim 가천대학교길병원안과학교실 Department of Ophthalmology, Gachon University Gil Hospital 660