Research in Vestibular Science Vol. 16, No. 2, June 2017 Review pissn 2092-8882, eissn 2093-5501 https://doi.org/10.21790/rvs.2017.16.2.47 근거중심으로살펴본수평반고리관이석증치료의최신지견 서남대학교의과대학명지병원이비인후과 심대보 Update of Treatment for Horizontal Canal Benign Paroxysmal Positional Vertigo: Evidence-Based Approach Dae Bo Shim Department of Otorhinolaryngology, Myongji Hospital, Seonam University College of Medicine, Goyang, Korea Received May 20, 2017 Revised May 23, 2017 Accepted May 23, 2017 Corresponding Author: Dae Bo Shim Department of Otorhinolaryngology, Myongji Hospital, Seonam University College of Medicine, 55 Hwasu-ro 14beon-gil, Deokyang-gu, Goyang 10475, Korea Tel: +82-31-810-5451 Fax: +82-31-969-0500 E-mail: lovend77@gmail.com Copyright c 2017 by The Korean Balance Society. All rights reserved. This is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Horizontal canal benign paroxysmal positional vertigo (HC-BPPV) can be classified as either the geotropic or apogeotropic subtype by the pattern of nystagmus triggered by supine head roll test. Most studies have reported the geotropic subtype as a more common pathophysiology in HC-BPPV than the apogeotropic subtype. According to the BPPV clinical practice guideline provided by the American Academy of Otolaryngology-Head and Neck Surgery and American Academy of Neurology in 2008, variations of the roll maneuver (Lempert maneuver of barbecue roll maneuver) are the most widely published treatments for HC-BPPV. In addition, various treatment techniques including Gufoni maneuver, Vannuchi-Asprella liberatory maneuver and forced prolonged positioning have been applied for HC-BPPV. However, the guideline failed to provide specific treatment guidelines for HC-BPPV based on evidence-based researches since only Class IV data on HC-BPPV treatment were available at the point of 2008 when the BPPV clinical practice guideline was published. This review article focused on the evidences of the efficacy of various maneuvers in the treatment of HC-BPPV published after the BPPV clinical practice guidelines of 2008. Res Vestib Sci 2017;16(2):47-52 Keywords: Benign paroxysmal positional vertigo; Semicircular canals; Treatment; Evidence-Based Medicine 서론수평반고리관양성돌발두위현훈 (benign paroxysmal positional vertigo, BPPV) 은체위검사중 supine head roll test 를통해나타난안진의양상에따라향지성아형 (geotropic subtype) 과원지성아형 (apogeotropic subtype) 으로구분하며, 대부분의연구들에서향지성아형이가장흔하며, 원지 성아형은드물다고보고하고있다 [1]. 최근바라니학회에서발표한 BPPV 진단기준에서는병태생리학적인관점에서반고리관결석증 (canalithiasis) 형태와팽대부마루결석증 (cupulolithiasis) 으로구분하여설명하고있으며, 반고리관결석증에서수평반고리관의앞쪽부분에유리이석이존재하는경우에는원지성아형의양상으로나타난다고설명하고있다 [2]. 2008년미국이비인후과학회 (American Academy 47
Res Vestib Sci Vol. 16, No. 2, Jun. 2017 of Otolaryngology-Head and Neck Surgery) 및미국신경과학회 (American Academy of Neurology) 에서각각진단및치료에대한연구들을근거수준 (level of evidence) 에따라 BPPV 의진단및치료에대한권고수준 (grade of recommendation) 을결정하여임상진료지침을제시하였다 [1,3]. 여기서, 근거수준이란근거의질적수준을평가하여등급화한지표로제시되는데, 근거의수집을통해얻은중재방법 (intervention) 의효과를측정한값이얼마나신뢰할만한지를나타내는척도라고할수있다 [4]. 2008년제시된 BPPV의임상진료지침에서수평반고리관 BPPV (horizontal canal BPPV, HC-BPPV) 의치료는다양하게변형한 Lempert 수기가가장널리사용된다고하였다. 또한 Gufoni 수기와강제지속자세 (forced prolonged positioning, FPP) 등의다양한치료수기들이 HC-BPPV의치료에적용되어왔다 [1,3]. 임상진료지침에서뒤반고리관양성돌발두위현훈 (posterior canal BPPV) 의치료는 Epley 수기나 Semont 수기를제시하였고, 이는높은근거수준의연구들을바탕으로강력히권고 (strong recommendation) 되었다 [1]. 그러나, HC-BPPV의치료에대한연구들은모두낮은근거수준에해당하여근거중심접근법 (evidence-based approach) 의관점에서특정치료를지침으로제시하지못하였다. 본종설에서는기존에제시된 HC-BPPV 치료법의종류들을알아보고, 최근에이치료법들의치료효과를비교분석한연구들을근거중심으로정리하였다. 해졌고, 해마다쏟아지는의학정보들이많아지면서의사개인이단독으로정보를소화하는일이점차힘들어졌다. 예를들어 1990 1995년사이에고혈압과관련된논문들만약 14,000건가량출판되었는데, 의사개인이스스로이내용들을모두파악하기란사실상불가능했다. 당시의료전문가들은이러한상황에서의학의객관성과투명성을재고할수있는새로운방법들을모색하는동시에수많은의학정보들을관리할수있게돕는기술들을발전시켰는데, 그과정에서등장한것이바로근거중심의학이다 [8,9]. 현재근거중심의학의아버지로불리우는스코틀랜드출신의의학자 Archie Cochrane은과학적방법에기초한의학적판단의필요성을주장했으며, 캐나다맥마스터대학의 David Sackett과그의동료들은임상역학 (clinical epidemiology) 분과를처음으로설립하고, 적절한과학적증거의위계를설정할방법론을마련했다 [10,11]. Sackett 등은초기에비평적분석 (critical appraisal) 으로명명하는논문을연제하며그들의연구활동을공유하고자노력했으며, 이후이러한 비평적분석 에서부터의료진료에서의새로운접근법으로서 근거중심의학 이태동하게되었다 [11]. 근거수준의분류 (Classification of evidence) 는각기관이나협회마다조금씩다르게제시하고있으며, 진단이나검진과치료등에따라서약간의변형된분류기준을사용하고있다. 하지만, 대부분의분류에서근거수준의위계는상기한미국질병예방관리본부의분류와같다 (Fig. 1) [12]. 본 론 1. 근거중심의학과근거수준 (evidence-based medicine and level of evidence) 근거중심의학 (evidence-based medicine) 은 1991년 Guyatt [5] 가처음으로명명하였으며, 초기에는 임상에서의사결정의기초로서발표된연구를분석하는체계적인접근법 으로정의하였다. 그후, 1996년 Sackett 등 [6] 은이용어를 각환자들의치료에있어서임상진료연구로부터얻은현재최상의증거의양심적이고합리적인사용 이라고더욱공식적으로정의하였다. 이러한근거중심의학에대한논의는 1990년대명명되기훨씬오래전부터있었지만, 여러사회적, 물질적상황들이맞물린 1980년대말이되어서야등장할수있었다 [7]. 당시진료정보에대한환자들의알권리요구와같은다양한사회적압력들이의료계에가 Fig. 1. Hierarchy of research designs and levels of scientific evidence (From National Health and Medical Research Council. Available from: https://www.nhmrc.gov.au/_files_nhmrc/file/guidelines/developers/ nhmrc_levels_grades_evidence_120423.pdf [12]). 48
심대보. 수평반고리관양성돌발두위현훈의치료최신지견 이에따르면, 증례보고 (case report) 는특정한개별환자에게수행한의학적처치의과정과결과를상세히서술한것으로가장낮은수준의과학적증거이다. 보다높은수준의증거는환자-대조군연구 (case-control study), 코호트연구 (cohort study), 그리고무작위대조군시험 (randomized controlled trial) 의순이다. 무작위대조군시험은연구대상이되는집단을무작위로선정한후, 이중한집단에연구목적이되는약물혹은치료를제공하고그집단과대비될반대집단에위약 (placebo) 처치를한후일정기간추적관찰을통해그효과를검사하는방법이다. 가장최상의과학적증거는이무작위대조군시험들의결과를종합적으로분석한 체계적문헌고찰 (systematic reviews) 로, 이는특정주제에대해대규모무작위대조군시험들을비롯한모든의학문헌을체계적으로검색, 평가및요약분석하는작업이다 [12]. 앞에서기술한것처럼, 근거수준의분류법은임상학회나기관마다다양하게제시하고있으나, 본종설에서는 HC-BPPV의치료만을설명하기때문에미국신경과학회에서제시하고있는 치료중재에서의근거수준의분류법 을적용하여설명하고자한다 [3]. 병리학적상태가다름에도불구하고비슷한방식의치료방법을사용하고있다. Lempert 수기 ( 바비큐회전수기, Barbecue roll maneuver) 는병변의반대방향으로머리를 90 씩총 270 360 회전하여수평반고리관후완의유리이석을난형낭으로되돌리기위해고안되었다 [14]. 하지만, Tirelli 와 Russolo [19] 은원지성아형에서도중력과 360 회전을이용하여평대부마루의이석의치료를시도하여 82.2% 의치료율 (51/62명) 을보고하였다. 또한, FPP은환자에게병변방향으로 12시간동안누운자세를취하도록하여수평반고리관후완의반고리관결석증 ( 향지성아형 ) 을치료하기위해고안되었으나 [16], 많은연구자들이동일한방법으로원지성아형의치료에도적용하여왔다 [16,20,26]. Gufoni 수기는향지성아형과원지성아형의치료에서치료의방향을다르게하여각각의병리학적원인을해결하도록고안되었으나, 원지성아형의치료에서는치료시행중 3번째자세에서머리의회전방향이반대인 2가지변형방법이혼재되어사용되고있는실정이다 [17,21,24,25]. 3. 수평반고리관양성돌발두위현훈의치료에대한비교연구 2. 수평반고리관양성돌발두위현훈의치료 HC-BPPV의치료는향지성아형과원지성아형에따라치료를시행하며, 이는상기한병태생리학적원인에따른이석의위치와연관이있다. 1985년 McClure [13] 가수평반고리관이석증을소개한이후다양한치료법이소개되었으며, 대부분의치료법은 50% 100% 의치료율을보이나낮은근거수준으로임상의들의선호및환자의상황에따라시행되어왔다 (Table 1) [14-26]. HC-BPPV의향지성아형은병태생리학적으로수평반고리관의후완 (posterior arm) 내에존재하는이석 ( 반고리관결석증 ) 에의하는것으로, 치료들또한이후완에존재하는유리이석을난형낭내로되돌리도록고안되었다. HC-BPPV의원지성아형은병태생리학적으로대부분수평반고리관평대부마루에붙은이석에의해발생하는것 ( 팽대부마루결석증 ) 으로알려져있으며, 일부에서수평반고리관의전완 (anterior arm) 내에존재하는이석 ( 반고리관결석증 ) 에의하는것으로추정되어, 치료들또한이러한병태생리학적원인을해결하기위해고안되었다. Table 1에서확인하는것처럼, HC-BPPV의 2가지아형은 앞에서기술한것처럼, 2008년 BPPV 임상진료지침이제시되기전까지는 HC-BPPV의치료에대한연구들이모두근거수준이낮은 Class IV의연구들만보고되었다. 하지만, 임상진료지침이발표된이후부터는기존의치료방법들에대한근거를만들기위해많은연구자들이근거수준이높은비교연구들을발표하였다. 본종설에서는 HC-BPPV 의비교연구들을 2가지아형에따라정리하였다. Table 1. Various treatments for the two subtypes of horizontal canal benign paroxysmal positional vertigo Geotropic subtype Apogeotropic subtype Lempert (barbecue) Lempert (barbecue) maneuver [19] maneuver [14] Forced prolonged Forced prolonged maneuver [16,20,26] maneuver [16] Gufoni maneuver Cupulolith repositioning maneuver [18] [15,21,22] Therapeutic head shaking [16,23] Appiani maneuver [17] Gufoni maneuver [21,23-25] 49
Res Vestib Sci Vol. 16, No. 2, Jun. 2017 1) 향지성아형 HC-BPPV의향지성아형 (geotropic HC-BPPV, HC-BPPV [geo]) 은 Lempert 수기, FPP, Gufoni 수기와이치료들의조합을통해치료한다. Table 2에서는 HC-BPPV (geo) 의치료방법들의치료효과를비교한연구들을정리하였다 [21,22, 24,27,28]. 1998년 Nuti 등 [27] 은 92명의 HC-BPPV 환자들을대상으로치료하여 36명은 Lempert 수기를 38회시행하여 24명 (63%) 에서호전되었고, 남은 56명과 Lempert 수기로치료되지않은 7명을추가한 63명에서 FPP로치료하여 46명 (73%) 에서치료효과를확인하였다. 2011년 Korres 등 [28] 은전향적연구를통해각각다른시기에 Lempert 수기, FPP, 그리고 Gufoni수기로치료를시행하였다. 이연구에서는 Gufoni 수기와 FPP가 Lempert 수기보다효과가좋다고보고하였다. 2011년 Casani 등 [24] 은전향적무작위대조군시험을통하여 Lempert 수기와 FPP를함께시행한치료군 (barbecue roll maneuver [BBQ]+FPP군) 54명과 Gufoni 수기치료군 58명을비교하여 30일간추적관찰하였을때, Gufoni 치료군의치료율이 93% 로 BBQ+FPP 치료군 (81%) 보다더효과가있다고보고하였으나, 통계적으로유의한차이를보이지는않았다. 2012년 Kim 등 [22] 이시행한전향적다기관무작위대조군시험에서는 Lempert 수기, Gufoni 수기와함께 Sham 수기를비교분석하였다. 이때각각 2번의치료직후 Sham 치료군보다 Lempert 수기및 Gufoni 수기의치료효과가유의하게좋은것을확인하였으나, 두치료간에는치료효과의차이를확인할수없었다. 2013년 Mandala 등 [21] 은전향적무작위대조군시험을통하여 Gufoni수기치료군 27명을 Sham수기치료군 26명과비교하여, Gufoni 치료군의치료율이 88.9% (24/27명) 로 Sham수기치료군보다유의하게치료효과가있다고보고하였다. 이들 2개의다기관무작위대조군시험들은 Class I 연구로서 HC-BPPV (geo) 의치료방법에대한높은근거수준을제시하고있다 [21,22]. 2) 원지성아형 HC-BPPV의원지성아형 (apogeotropic HC-BPPV, HC-BPPV [apo]) 은상기한병리학적소견에따라치료방법이달라질수있으나, 대부분의이전연구들에서는병리학적소견에관계없이 Table 1에나열한치료들을시행하였으며, 최근발표되고있는무작위대조군시험에서도이러한기존의치료방법들을비교하여치료효과들을비교분석하고있다 (Table 3) [21,23,25,29]. 2009년 Oh 등 [23] 은 103명의 HC-BPPV (apo) 환자들을대상으로무작위대조군연구를시행하였으며, 1회의 Gufoni 수기로치료한 52명의환자중 9명 (17.3%) 만이호전된반면, 1회의치료적두진 (therapeutic head shaking procedure) 으로치료한 51명의환자중 19명 (37.3%) 이호전되어, Gufoni 수기보다는치료적두진이더효과적인치료라고보고하 Table 2. Comparison of previous studies on the treatment of geotropic horizontal canal benign paroxysmal positional vertigo Authors (year) No. of patients Therapeutic maneuvers & resolution rates (%) Level of BBQ FPP BBQ+FPP Gufoni evidence Nuti et al. (1998) [27] 101 (BBQ:FPP=36:63) 63.0 73.0 - - Class IV Korres et al. (2011) [28] 60 (BBQ:FPP:Gufoni=13:29:18) 38.4 75.8-88.9 Class III Casani et al. (2011) [24] 132 (BBQ+FPP:Gufoni=54:58) - - 81.0 93.0 Class III Kim et al. (2012) [22] 170 (BBQ:Gufoni:Sham=56:64:50) 69.1 - - 60.9 Class I Mandala et al. (2013) [21] 53 (Gufoni:Sham=27:26) - - - 88.9 Class I BBQ, barbecue roll maneuver; FPP, forced prolonged position; No., number. Table 3. Comparison of previous studies on the treatment of apogeotropic horizontal canal benign paroxysmal positional vertigo Authors (year) No. of patients Therapeutic maneuvers & resolution rates (%) BBQ THS Gufoni V-A Level of evidence Oh et al. (2009) [23] 103 (THS:Gufoni=51:52) - 37.3 17.3 - Class II Kim et al. (2012) [25] 157 (THS:Gufoni:Sham=54:52:51) - 62.3 73.1 - Class I Riga et al. (2013) [29] 132 (BBQ:Gufoni:V-A=28:252:81) 75.0-57.9 65.4 Class III Mandala et al. (2013) [21] 19 (Gufoni:Sham=10:9) - - 40.0 - Class I BBQ, barbecue roll maneuver; No., number; THS, therapeutic head shaking procedure; V-A, Vannucchi-Asprella maneuver. 50
심대보. 수평반고리관양성돌발두위현훈의치료최신지견 였다. 2012년 Kim 등 [25] 이시행한전향적다기관무작위대조군시험에서는치료적두진과 Gufoni 수기를 Sham 수기와비교분석하였다. 이때, 각각 2번의치료직후 Sham 치료군보다치료적두진및 Gufoni 수기의치료효과가유의하게우수한것을확인하였으나, 치료적두진과 Gufoni 수기의치료간에는치료효과의차이를확인할수없었다. 2013년 Riga 등 [29] 은메타분석 (meta-analysis) 을통해 1990 년부터 2012년까지 20개의연구를분석하여 Gufoni 수기, 바비큐회전수기, Vannucchi-Asprella 수기의치료결과를비교하였다. 그결과, Gufoni 수기는 1회의치료로 57.9% (146/252명) 의치료율을보였고, HC-BPPV (apo) 의모든병리학적원인에효과가있다고보고하였다. 바비큐회전수기와 Vannucchi-Asprella 수기는각각 75% (21/28명), 65.4% (53/81명) 의치료율을보였으나, 대부분의연구에서 5 10회의치료를시행하였고, 이들은수평반고라관전완의반고리관결석증치료에효과가있다고보고하였다. 이연구는메타분석이라는좋은연구방법을사용하였으나, 포함된기존의연구들이대부분 Class III, IV의낮은근거수준의연구들이어서 Class III로분류된다 [29]. 2013년 Mandala 등 [21] 은전향적무작위대조군시험을통하여 Gufoni 수기치료군 10명을 Sham 수기치료군 9명과비교하여, Gufoni 치료군의치료율이 40% 로 Sham 수기치료군보다유의하게치료효과가있다고보고하였으며, Class I의높은근거수준의연구임을강조하였다. 결론 HC-BPPV의치료는반고리관결석증또는팽대부마루결석증의병태생리적상태에따라다양한치료수기를사용하고있다. 최근까지발표된연구들의결과에서는, 두병태생리형태모두에서어떠한치료수기도아직까지다른치료수기에비해우월한치료성적을보이는방법은없으며, 1회치료효과도 17.3% 에서 93% 까지매우다양하게보고되고있는실정이다. 하지만, 근거수준이높은 Class I 및 Class II 연구의결과로볼때, HC-BPPV (geo) 에서는 Barbecue 수기와 Gufoni 수기가추천되며, HC-BPPV (apo) 에서는 Gufoni 수기와치료적두진이추천된다. HC-BPPV의치료를시행할때, 대부분의경우치료시병변의방향이중요하며, 각병태생리의상태가치료를결정하는중요요소임을숙지해야한다. 그러므로, 치료전에이환된병변의방향및정확한병태생리형태를확진하는것이중요하며, 치료의선택은환자의나이, 전신상태, 향후추적관찰가능여부등을고려하여치료방법을결정하고, 치료후환자의병태생리의변화 (canal conversion) 나치료효과의판정을통해추가적인치료를고려하는것이필요하다. 향후 HC-BPPV의치료에대한근거수준이높은 Class I 및 Class II 연구들이늘어나, BPPV의새로운임상진료지침에서 HC-BPPV의치료의권고수준을결정하는토대가마련되기를기대한다. 중심단어 : 양성돌발두위현훈, 반고리관, 치료, 근거중심의학 CONFLICT OF INTEREST No potential conflict of interest relevant to this article was reported. REFERENCES 1. Bhattacharyya N, Baugh RF, Orvidas L, Barrs D, Bronston LJ, Cass S, et al. Clinical practice guideline: benign paroxysmal positional vertigo. Otolaryngol Head Neck Surg 2008;139: S47-81. 2. von Brevern M, Bertholon P, Brandt T, Fife T, Imai T, Nuti D, et al. Benign paroxysmal positional vertigo: diagnostic criteria. J Vestib Res 2015;25:105-17. 3. Fife TD, Iverson DJ, Lempert T, Furman JM, Baloh RW, Tusa RJ, et al. Practice parameter: therapies for benign paroxysmal positional vertigo (an evidence-based review): report of the Quality Standards Subcommittee of the American Academy of Neurology. Neurology 2008;70:2067-74. 4. Guyatt GH, Oxman AD, Vist GE, Kunz R, Falck-Ytter Y, Alonso-Coello P, et al. GRADE: an emerging consensus on rating quality of evidence and strength of recommendations. BMJ 2008;336:924-6. 5. Guyatt GH. Evidence-based medicine. ACP J Club 1991; March/April:A-16. 6. Sackett DL, Rosenberg WM, Gray JA, Haynes RB, Richardson WS. Evidence based medicine: what it is and what it isn't. BMJ 1996;312:71-2. 7. Claridge JA, Fabian TC. History and development of evidence-based medicine. World J Surg 2005;29:547-53. 8. Seo KH, Lee SH, Shin ES, Lim SM, Jang JE, Jung YM, et al. Trend analysis of grading systems for level of evidence and strength of recommendation. J Korean Med Assoc 2011;54:758-68. 9. DeVries JG, Berlet GC. Understanding levels of evidence for scientific communication. Foot Ankle Spec 2010;3:205-9. 10. Sur R, Dahm P. History of evidence-based medicine. Indian 51
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