J Korean Surg Soc 2011;80:96-102 DOI: 10.4174/jkss.2011.80.2.102 원 저 유방확대술후코히시브실리콘겔유방보형물파손 엠디클리닉, 1 성균관대학교의과대학삼성서울병원영상의학교실 이상달ㆍ김성훈ㆍ한부경 1 Rupture of the Cohesive Silicone Gel Implant after Breast Augmentation Sangdal Lee, M.D., Ph.D., Sung Hoon Kim, M.D., Boo-Kyung Han 1 MD Clinic, 1 Department of Radiology, Sungkyunkwan University School of Medicine, Seoul, Korea Purpose: Breast augmentation with cohesive silicone gel implant has been popular but there remains the risk of implant rupture. We investigated the diagnosis and treatment of cohesive gel implant rupture. Methods: Ten cases of cohesive gel implant rupture between August 2006 and August 2010 in ooo were reviewed in this study. The diagnostic role of Magnetic resonance imaging (MRI) and ultrasonography (US), and operative findings of cases were studied retrospectively. Results: The mean interval from previous surgery was 14.7 months ranging from 3 to 44 months. Nine cases were visited due to abrupt changes in texture of implants and 1 case for revision of capsular contracture. Seven of 10 cases had capsular contracture, simultaneously. We diagnosed the first case by US and MRI but only US was used in the other 9 cases. US showed discontinuity of the implant membrane and multiple parallel echogenic lines within the implant interior (stepladder sign), and MRI showed the presence of multiple curvilinear low-signal-intensity lines seen within the high-signal-intensity silicone gel (linguine sign). All the ruptured gel remained in place within the capsule and did not migrate into the surrounding area. Surgeries were implant replacement in 3, replacement with capsulectomy in 6 with capsular contracture, and subpectoral conversion with capsulectomy and mastopexy in 1 case. Conclusion: US without MRI has asatisfactoryrole in the screening method for detection of cohesive silicone gel implant rupture in symptomatic cases. Ruptured implants were removed and replaced easily due to their highly cohesive nature. (J Korean Surg Soc 2011;80:96-102) Key Words: Rupture, Cohesive silicone gel, Breast implant 중심단어 : 파열, 코히시브실리콘겔, 유방보형물 서 1963년 Cronin과 Gerow(1) 가실리콘유방보형물을소개한이후최근코히시브실리콘겔까지유방보형물은진화를 책임저자 : 이상달, 서울시강남구신사동 664-13 135-897, 엠디클리닉 Tel: 02-542-0081, Fax: 02-542-4443 E-mail: dahl65@hanmail.net 접수일 :2010 년 10 월 26 일, 게재승인일 :2010 년 12 월 21 일 론 거듭해왔다. 하지만실리콘유방보형물의안전성논란도만만치않았으며 (2-6) 1980년대말부터본격적으로제기되어온논란끝에 1992년미국 FDA는실리콘보형물사용을금지하기도하였다. 하지만우수한촉감과자연스러움으로꾸준한관심을받으며많은나라에서계속사용되였고지속적인연구결과실리콘유방보형물의안전성을입증한여러연구결과들이보고되었다.(7-9) 1993년미국 McGhan 사 (Santa Barbara, California) 는기존의실리콘내용물의응집력을높여처음으로코히시브실리콘겔유방보형물을개발하였는데,(10) 이후다른제조사들도생산을시작했지 96
Sangdal Lee, et al:rupture of the Cohesive Silicone Gel Implant after Breast Augmentation 97 만북미에선사용이제한된상태로미국 FDA는여러데이터를검토하였다.(11-14) 2006년미국 FDA는그동안의데이터를바탕으로코히시브겔보형물의안전성을인정하여사용을승인하기에이르렀으나몇가지논란의여지는남아있다. 식염수보형물과는달리코히시브겔보형물의경우파열여부를쉽게알기어려워미국 FDA는보형물파열을진단하기위해수술후 3년뒤부터매 2년마다 Magnetic Resonance imaging (MRI) 검사시행을권고하였다. 그러나 MRI가유방보형물의파열을진단함에있어유방촬영술이나초음파검사보다높은정확도를지니고있음에도불구하고 (15,16) 선별검사로써고가의검사인 MRI를시행하기에는논란의여지가있다.(17,18) 또한코히시브겔보형물의특성상파손시에도높은응집력으로인해피막밖으로퍼질가능성이희박함에도불구하고지나친불안의대상이되고있는점도수정이필요하다. 이미유방암으로유방절제한여성들의유방재건술에효과적인유방보형물로자리잡고있지만점차늘어나는유방암발병에도불구하고보형물의안전성에대한지나친우려가유방재건수술에대해거부감으로작용하여삶의질향상의기회를떨어뜨리고있다. 또한유방확대술후에도보형물손상에대한두려움으로유방검진을하고자하는여성들도늘고있는실정이다. 보형물손상은수술받은환자들에겐불안요인이며재수술의중요한요인이되기도한다.(19) 이에저자들은유방보형물삽입수술후코히시브겔보형물이파손된경우의임상경험과 MRI 촬영및초음파를이용한보형물파열진단의유용성, 그리고수술소견및보형물교체수술의결과에대해알아보고자한다. 방법 2006년 8월부터 2010년 8월까지엠디클리닉가슴성형센터에서코히시브실리콘겔유방보형물파열로재수술을시행한 10예에대해후향적으로조사하였다. 연구대상의선정기준은본원또는타병원에서코히시브겔유방보형물을이용하여유방확대술을시행받은환자중보형물파열로본원에서진단하에수술한환자를대상으로하였으며, 식염수보형물또는하이드로겔보형물을삽입했던환자는배제하였다. 이중 7예는타병원에서수술한후재수술을위해내원한경우이고 3예는본원에서수술한후재수술한경우였다. 전예에대해수술전증상, 기존수술로부터의기간, 초음파 (General Electric, Fairfield, USA) 검사소견, 그리고수술소견을관찰하였고첫예의경우초음파검사후 MRI (Phillips, Amsterdam, Netherland) 촬영을병행하였다. 한편파열이의심되었기에유방을압박하는유방 X선촬영은시행하지않았다. 10예모두전신마취하에수술을시행하였고수술내용은파열된보형물제거와구형구축이동반된 7예에대해피막절개또는절제술을시행하였고반대쪽역시구형구축이동반되었거나환자들이동시에모양이나크기교정을원하여파열된보형물뿐아니라반대쪽보형물도모두교체하였다. Table 1. Demography of patients Case No. Age (year) Time to rupture (month) US* MRI Contracture Implant volume (cc) Simultaneous capsulectomy Rupture type 1 28 12 Yes Yes Yes 225 Yes Intracapsular 2 26 10 Yes No No 225 No Intracapsular 3 25 14 Yes No No 250 No Intracapsular 4 41 12 Yes No Yes 250 Yes Intracapsular 5 29 12 Yes No No 275 No Intracapsular 6 34 5 Yes No Yes 250 Yes Intracapsular 7 32 24 Yes No Yes 300 Yes Intracapsular 8 37 3 Yes No Yes 225 Yes Intracapsular 9 30 44 Yes No Yes 250 Yes Intracapsular 10 24 11 Yes No Yes 190 Yes Intracapsular *US = ultrasonography; MRI = magnetic resonance imaging.
98 J Korean Surg Soc. Vol. 80, No. 2 Fig. 1. Ultrasonography showed discontinuity of the implant membrane and multiple parallel echogenic lines within the implant interior (stepladder sign). 결 연령은 25세부터 41세까지있었고평균연령은 30.6세였다. 처음수술후보형물파열까지걸린기간은 3개월부터 44개월까지였고평균 14.7개월이소요되었다. 10예중 9예는스무스형코히시브실리콘겔유방보형물이었고, 1예는텍스쳐형코히시브실리콘겔유방보형물이었으며, 3예는좌측, 7예는우측에서발생하였다 (Table 1). 이중 9예에서갑자기좋아진촉감으로환자스스로보형물손상을의심하였다. 이들 9예중 4예는이전에구형구축발생으로재수술을한경험이있었는데내원당시에도촉감이좋은편은아니었고나머지 5예는문진상촉감이단단하다가갑자기좋아졌다고하였는데내원당시에구형구축현상이관찰되었으며다른 1예는좋은촉감을유지해왔으나느낌이이상하여보형물파열을의심한경우였다. 최초경험한 28세의예에서는이미한번의구형구축발생으로재수술을한예였으며재수술후경과관찰중갑자기촉감이좋아져유방초음파와 MRI검사를통해파손여부를확인하였다. 초음파소견상보형물공간내의에코가비균일하게증가되어있으면서여러층의지나가는선들이보이는 사다리징후 (stepladder sign) 소견을보였고 (Fig. 1) MRI소견상파손된보형물껍질이여러개의구불구불한저신호강도선이포개져있는모양으로보이는 링귀니징후 (linguini sign) 소견을보여전형적인피막내파열을시사하는소견을보였 과 Fig. 2. MRI showed the presence of multiple curvilinear low-signal-intensity lines seen within the high-signal-intensity silicone gel (linguine sign). 다 (Fig. 2). 이후에경험한예들중 8예의경우촉진후초음파검사만으로 사다리징후 등의특이소견을보여보형물파손을확진할수있었다. 구형구축부작용으로재수술을위해내원한 1예의경우수술전파열로인한자각증상이없었고초음파검사로보형물파열을진단하지못한상태로피막제거술시행중우연히보형물파열을발견하였는데파열이미미하여보형물은그형태를유지하고있었고보형물을압박하지않으면보형물외부로실리콘겔이누출되지않은피막내파열이었다. 수술소견상 10예모두누출된실리콘은피막내에국한되어있었으며이중 9예에서는높은응집성으로따로떨어져있지도않았고완전제거가용이하였고 (Fig. 3), 수술소견상보형물이파열되지않은위양성에해당되는환자는없었다. 하지만 1예의경우에는수술전초음파소견상좌측쇄골하방까지연결되어있는겔음영을관찰할수있었는데수술소견상누출된겔이쇄골하방까지퍼져있었으나피막내였으며겔이따로떨어지지않고연결되어있어완전제거는어렵지않았다. 구형구축이동반되지않은 3예에대해서는피막내소독을시행한후기존피막을제거하지않은채동일한종류와크기의보형물로교체하였고 6예에대해서는구형구축을해결하기위해부분피막제거술을시행한후보형물을교체하였으며, 1예는구형구축해결과함께기존보형물이유선하삽입으로되어있고처진유방교정을원해양쪽모두피막제거후 (Fig. 4) 근육하삽입으로전환하여보형물을교체하고유방확대술과함께유방거상술을병행하였다. 위의 1예를제외하고나머지 9예모두보형물은근육하
Sangdal Lee, et al:rupture of the Cohesive Silicone Gel Implant after Breast Augmentation 99 Fig. 3. Ruptured gel was highly cohesive and removed completely. Fig. 4. Capsulectomy. 에삽입되어있었다. 수술후 3 28개월이지난현재 10예모두보형물재파열이나구형구축현상은발생하지않았다. 고찰 유방확대술의역사는 1895년지방종을이용한유방확대술이처음으로보고된이래밀랍, 바세린, 에폭시수지등화학물질을유방에주입하는시술이시행되다가 1961년에 Uchida(5) 가유방에주입이가능한실리콘에대해발표하였다. 1963년에 Cronin과 Gerow(1) 는점성의실리콘겔을두꺼운실리콘외피에담아 Dow Corning사를통해최초의실리콘겔유방보형물을소개하였다. 이후유방확대술시삽입되는실리콘겔보형물의안전성에대해우려하는보고들이지속적으로발표되었다. 1964년에실리콘겔보형물을삽입한여성에서결합조직질환의증상을보이는환자에대한보고 (2) 가있었으나그리주목을받지못한채사용되어오다가, 1980년대에들어서는실리콘겔보형물과여러가지다양한혈관, 자가면역, 류마티스질환등과의연관성에 대한보고 (4,6) 가관심을끌게되었다. 또한유방암발생에관련해서도문제제기가있었는데 2,4-toluendiamine이유방암발생을일으킨다는보고 (3) 를근거로하여실리콘겔유방보형물을싸고있는외피가 2,4-와 2,6-toluenediisocyanate 의합성물이기때문에유방암의발생에기여를할수도있다는가능성이제기되었다. 실리콘겔유방보형물의안전성에대한논란속에서 1992년미국 FDA는실리콘겔유방보형물사용을전면금지하였다. 그러나시간이지나면서추가적인연구에의해실리콘보형물의안전성을입증하는결과들이발표되었다. 실리콘이보형물로부터누출되어혈액을통해전신적인반응과전신질환을야기한다는논리에대해서는실리콘농도가보형물을싸고있는피막조직과액와림프절에서만국소적으로증가 (20) 하여자가면역, 류마티스질환등과는관계가없음을입증하였다.(9) Holmich 등 (21) 은 64명의 96개의파열된실리콘보형물에대해파열을진단하고수술적치료를하지않고 2년간추적관찰만시행한전향적연구결과를발표하였다. 이논문에서는자가면역질환과전신질환에대한영향을알아보고자모든환자에서 antinuclear antibodies, rheumatoid factor immunoglobulin M, cardiolipin immunoglobulin G와 immunoglobulin M antibodies 등을검사하였으며실리콘보형물파열과는상관관계가없었다고말하고있어이연구역시실리콘보형물의안정성을뒷받침하고있다. 또한유방암발생과관련하여실리콘유방보형물을이용한유방확대술을받은환자의추적관찰기간이쌓이면서유방암발생과관련이없다는여러연구결과가보고되었다.(7,14,22) 이렇듯실리콘겔유방보형물의안전성을입증하는여러연구들과함께물리적으로개선된코히시브실리콘겔보형물의등장으로인해 2006년미국 FDA는실리콘겔유방보형물을다시승인하게되었다.
100 J Korean Surg Soc. Vol. 80, No. 2 그러나미국 FDA는보형물의파손여부를진단하기위해유방보형물을이용한유방확대수술후첫 3년이후매 2년마다유방 MRI 검사를하도록하였다. Cunningham과 McCue(23) 는코히시브겔유방보형물의파열에대해 6년동안보형물파열확률은 3.7% 라고보고하였으며, Heden 등 (11) 은평균추적관찰기간 6년동안 1% 의보형물파열이확인또는의심되었다고보고하고있다. 이처럼낮은보형물파열율의이유로 Heden 등 (24) 은응집력이높은코히시브겔이보형물내부를단단히채우고있어그결과전단력 (shearing force) 이낮아져보형물외피가덜닳게되기때문이라고설명하였다. 실리콘보형물파열의원인으로는시간경과로인한내구력약화, 외부의물리적손상, 구형구축등을생각할수있다. 본연구에서는수술후보형물파열진단까지평균 14.7개월이걸렸는데이는국내에서코히시브겔사용이 2007년에승인된점을감안할때시간경과에의한내구력약화때문이라기보다물리적손상과구형구축으로인한파열이라고생각된다. 저자들이경험한예에서도 10예중 7예에서구형구축이선행되었고, 4예는이미구형구축으로재수술을시행하였던경우였다. 구형구축현상이생길경우지속적인섬유조직의압박과함께이를완화하기위해무리한마사지가이런물리적인압박이원인으로작용했을가능성이있다. 저자들이수술한코히시브겔파열의 10예의경우 1예를제외하고 9예에서모두촉감이갑작스럽게변하는자각증상이있었으며, 9예모두에서수술전초음파로 사다리징후 (steplader sign) 을관찰하여보형물파열을진단할수있었다. 보형물파열이있을경우초음파상에서보형물피막과평행하는직선의고에코영상이연속되는사다리징후를볼수있으며이는보형물파열을진단하는데있어가장중요한소견이된다.(25) 수술소견상 10예모두피막내파열이었으며피막밖으로실리콘겔의퍼짐이없어보형물제거가용이하였는데이는코히시브겔의높은응집력으로인한현상으로 (Fig. 5) 여러논문 (11,25) 에서도같은의견이었다. 앞서말한 Holmich 등 (21) 의연구결과에의하면파열로진단된 96개의보형물중 77개가피막내파열 (intracapsular rupture) 이였고, 추적관찰한 2년간이중 69개 (90%) 는실리콘이피막밖으로흘러나오지않고처음진단된상태를유지하고있었으며, 처음진단될당시피막외파열 (extracapsular rupture) 이였던 19개의보형물중 16개 (84%) 도실리콘이 2년간별다른변화없이최초진단되었던당시의상태를유지하 고있었다고말하고있으며, 특히파열된실리콘보형물의 72% 는 1987년이전에만들어진제 2세대보형물이었다. 이는실리콘보형물의높은응집력을보여주는결과이며현재사용되는진화된실리콘보형물인코히시브겔보형물은실리콘의응집력을더욱강화하였기에저자들역시실리콘겔의퍼짐없이보형물제거가용이하였다. 유방보형물의파열여부를진단하는데있어 MRI의민감도는 72 94%, 특이도는 85 100% 로보고하고있고,(16,26) 초음파의경우민감도는 70%, 특이도는 92% 로보고하고있어 (27) 유방보형물파열여부진단을위한영상학적검사로는 MRI가초음파보다정확도에있어다소앞서는것으로알려져있다. 그러나코히시브겔유방보형물파열율이매우낮고, 대부분피막내파열이며상당한기간동안겔이보형물외피내에국한되어있으므로파열로인한심각한합병증이없고응급상황이아니기에보형물파열을선별검사하기위해코히시브겔을삽입한모든환자에대해고가의 MRI 검사를하는것은높은의료비지출과함께환자에게큰불편을초래하게될것이다. McCarthy 등 (28) 은선별검사로서의 MRI가증상이있는환자군에서는양성예측률이 80% 이상이되지만증상이없는환자군에서는 80% 미만이되므로 MRI가선별검사의수단으로서는아직부적합하다고주장하였다. 이런문제점으로인해보형물을이용한유방확대술후보형물상태의평가를위한가이드라인이여러논문 (29,30) 에서제시되고있는데그주요내용은증상이있는환자에있어서유방촬영과초음파를실시하고파열이확실하거나의심스러울경우에 MRI로진단에도움을받는다는것이며, 이는본저자들과도일치하는의견이다. 조사대상중 1예는타영상의학과의원에서 MRI 촬영상보형물파열여부진단이되지않아내원하여초음파검사로확인한예가있었다. 또한본연구내용과는관계없으나초음파검진이정확했고 MRI 검사가오진이었던예가있었다. 수술한지 2년경과한환자로우측흉통을주소로보형물파열을염려하던환자였는데본저자의초음파검사상보형물파열이없음을확인하였으나통증때문에종합병원에서성형외과진료후 MRI 검사를시행한결과영상의학과판독상피막외파열진단을받아다시내원하여수술한예였다. 수술소견상보형물파열은없었고 MRI에서겔누출로의심한부분에섬유조직비대로인한육아종만이관찰된경우였다. 이러한예들은 MRI가초음파에비해보형물파열진단에절대적우위에있지않다는걸의미하며보다중요한건검진의사의경험이라고할수있다.
Sangdal Lee, et al:rupture of the Cohesive Silicone Gel Implant after Breast Augmentation 101 저자들이경험한증례의경우 1예만초음파검사후 MRI를추가적으로시행하여영상의학과전문의의이중판독을통해확진하였으며, 나머지 9예중 8예에대해서는외과의사에의한초음파검사만으로보형물파열을진단할수있었다. 초음파검사는비용이비싸지않고짧은시간내에가능하며 MRI가금기인경우의환자에대해서도외래에서간편하게검사할수있는장점이있고, 이학적검사와함께적용한다면선별검사로써충분히사용될수있는정확도를지니고있다. 또한파열된보형물에서내용물이누출됨에따라더욱확실한진단이가능해지기때문에반복검사를하기에시간적, 경제적부담이없는초음파검사가효과적이라할수있다. 수술전초음파검사로진단하지못했던 1예의경우는구형구축으로인한재수술시행을앞둔경우로수술중확인할수있었고수술소견상미세한누출로 MRI검사로도확인이될수없는경우였으며이런경우시간이지남에따라겔이보형물외피밖으로누출될경우초음파검사로도확인이할수있었기에수술전진단되지않은사실이선별검사로서 MRI가필요하다는걸의미하는건아니라할수있다. 또한실리콘이누출될경우주변조직으로퍼질것이라는우려와는달리보형물주변에형성되어있는섬유질의피막으로인해응집력이높은실리콘겔이피막외부로퍼질수없다는점은불확실한소견의경우초음파검사를반복하여시행할수있는시간적여유를줄수있고보형물제거또는교체를용이하게하여코히시브겔보형물을사용한유방재건술이나유방확대술의안전성을높여줄수있다고사료된다. 결론 코히시브실리콘겔유방보형물의파열진단에있어선별검사로유방초음파가효과적이며유방초음파의소견상파열이확실할경우에는굳이 MRI를추가적으로시행할필요는없고, 초음파의소견이불확실할경우에한하여선택적으로 MRI를시행해도충분히진단이가능하리라사료된다. 또한코히시브실리콘겔유방보형물은높은응집력으로파열시에도보형물주변의피막내에국한되어있어응급수술은필요하지않고비교적제거나교체수술이용이하였다. REFERENCES 1) Cronin TD. Augmentation mammaplasty: a new "natural feel" prosthesis. Transactions of the Third international Congress of Plastic Surgery 1963:41-9. 2) Miyoshi K, Kobayashi Y. Hypergammaglobulinemia by prolonged adjuvanticity in men: disorders developed after augmentation mammoplasty. Jpn Med J 1964;2122:9-14. 3) National Toxicology Program. Bioassay of 2,4-diaminotoluene for possible carcinogenicity. Natl Cancer Inst Carcinog Tech Rep Ser 1979;162:1-139. 4) Endo LP, Edwards NL, Longley S, Corman LC, Panush RS. Silicone and rheumatic diseases. Semin Arthritis Rheum 1987;17:112-8. 5) Uchida J. Clinical application of crosslinked dimethylpolysiloxane, restoration of breast, cheeks, atrophy of infantile paralysis, funnel-shape chest, etc. Jpn J Plast Reconstr Surg 1961;4:303. 6) van Nunen SA, Gatenby PA, Basten A. Post-mammoplasty connective tissue disease. Arthritis Rheum 1982;25:694-7. 7) Berkel H, Birdsell DC, Jenkins H. Breast augmentation: a risk factor for breast cancer? N Engl J Med 1992;326:1649-53. 8) Duffy MJ, Woods JE. Health risks of failed silicone gel breast implants: a 30-year clinical experience. Plast Reconstr Surg 1994;94:295-9. 9) Sanchez-Guerrero J, Schur PH, Sergent JS, Liang MH. Silicone breast implants and rheumatic disease. Clinical, immunologic, and epidemiologic studies. Arthritis Rheum 1994; 37:158-68. 10) Tebbetts J. McGhan's biodimensional augmentation system cohesive gel mammary implants. Instructional video 55'. McGhan Medical Corporation 1993. 11) Heden P, Bone B, Murphy DK, Slicton A, Walker PS. Style 410 cohesive silicone breast implants: safety and effectiveness at 5 to 9 years after implantation. Plast Reconstr Surg 2006; 118:1281-7. 12) Janowsky EC, Kupper LL, Hulka BS. Meta-analyses of the relation between silicone breast implants and the risk of connective-tissue diseases. N Engl J Med 2000;342:781-90. 13) Lipworth L, Tarone RE, McLaughlin JK. Silicone breast implants and connective tissue disease: an updated review of the epidemiologic evidence. Ann Plast Surg 2004;52:598-601. 14) Bryant H, Brasher P. Breast implants and breast cancer--reanalysis of a linkage study. N Engl J Med 1995;332:1535-9. 15) Cher DJ, Conwell JA, Mandel JS. MRI for detecting silicone breast implant rupture: meta-analysis and implications. Ann Plast Surg 2001;47:367-80. 16) Ikeda DM, Borofsky HB, Herfkens RJ, Sawyer-Glover AM, Birdwell RL, Glover GH. Silicone breast implant rupture: pitfalls of magnetic resonance imaging and relative efficacies of
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