ORIGINAL ARTICLE Korean J Stroke 2007;9:134-141 연하곤란을동반한뇌병변환자들에서설골상부근육의전기자극치료 강원도재활병원재활의학과 1, 강원대학교의과대학재활의학과학교실 2, 서울대학교의과대학재활의학과학교실 3 김정환 1 이건재 2 김상준 3 Electrical Stimulation on Suprahyoid Muscles of the Brain Injury Patients with Dysphagia Jung Hwan Kim, MD 1, Kun Jai Lee, MD 2 and Sang-Jun Kim, MD 3 1 Department of Rehabilitation Medicine, Gangwon-Do Rehabilitation Hospital, Chuncheon, Korea 2 Department of Rehabilitation Medicine, Kangwon National University College of Medicine, Chuncheon, Korea 3 Department of Rehabilitation Medicine, Seoul National University College of Medicine, Seoul, Korea Background: Electrical stimulation has been recently used to treat the dysphagia in brain injury patients. We investigated the effect of electrical stimulation of suprahyoid muscles on the brain injury patients with dysphagia. Methods: This study was performed in the retrospective, non-concurrent age-matched comparative method. We selected 12 patients who received the electrical stimulation and the conventional dysphagia management and 12 age-matched ones who received only conventional dysphagia management. To evaluate the swallowing function, we used American Speech-Language-Hearing Association (ASHA) score, clinical dysphagia scale and functional dysphagia scale. Results: In the ASHA score and the pharyngeal portion in the functional dysphagia scale, the electrical stimulation group showed more improvement than the conventional dysphagia management group. In the clinical and functional dysphagia scale, there was no significant difference between two groups. Conclusion: Electrical stimulation on suprahyoid muscles has an additional effect in the treatment of dysphagia in brain injury patients when compared with only conventional management. (Korean J Stroke 2007;9:134-141) KEY WORDS: Suprahyoid muscle Dysphagia Electrical stimulation. 서 론 연하란구강내의음식물을위장관까지전달하는일련의기능을말하며여기에는중추및말초신경계의여러신경들에의해지배받는괄약근을비롯한많은두경부근육들과골격및기타연부조직들이복잡하게작용한다. 이러한연하작용경로중어느부위에이상이생긴경우이를연하장애, 삼킴장애혹은연하곤란이라하는데, 주요원인으로는뇌졸중, 뇌종양, 파킨슨씨병등이있으며특히뇌졸중환자들중 Address for correspondence: Sang-Jun Kim, MD Department of Rehabilitation Medicine, Seoul National University, College of Medicine, 28 Yeongeon-dong, Jongno-gu, Seoul 110-744, Korea Tel: +82-2-2072-3940, Fax: +82-2-743-7473 E-mail: guitarren@hanmail.net 연구비제공 : 산업자원부주관중소기업기술혁신개발 (S1011657). 37~78% 에서연하곤란이발생하는것으로알려질정도로뇌졸중의주요한합병증으로생각되고있다. 1 연하곤란의치료로현재이용되고있는방법으로는얼음조각삼키기, 인두부온도자극등이있으며최근인두부근육들을전기자극시연하곤란이호전된다는보고들이대두되고있다. 2-6 인두부전기자극의치료효과에대한기전은아직확립되지는않았으나, 전기자극으로유발되는근수축에의한근력강화라기보다는감각신경의자극에따른연하반사의촉진으로생각하고있다. 7 연하에관여하는근육들은설골을전, 상방으로움직이는악설골근, 전이복근 (anterior digastric), 이설골근 (geniohyoid) 과후두부를전, 상방으로움직이는갑상설골근 (thyrohyoid) 이있다. 이근육들이수축하면서후두부를전방이동시키고후두덮개를회전시켜음식물이기도로흡인되는것을막고, 134 Copyright c 2007 Korean Stroke Society ISSN 1229-4101
Jung Hwan Kim, et al. 인두부개구부를열어음식물이식도로통과하도록한다. 이러한근육들이약화된뇌병변연하곤란환자들에게이근육들을전기자극하려는노력들이시도되었으며, 5 설골상부근육을전기자극시정상인에서설골및후두부가상승한다는보고가있으나, 8 갑상설골근을자극시에는오히려설골이하강하여연하에방해가되는것으로알려져있다. 7 그러나연하곤란환자들에게설골상부를전기자극하여연하곤란치료에이용하려는시도는아직이루어지고있지않다. 따라서저자들은연하곤란을동반한뇌병변환자들에게기존의연하곤란전기자극치료기를이용하여설골상부를자극한후그치료효과를보고자하였다. 대상및방법 대상 2007년 1월부터 2007년 6월까지대학병원에내원한연하곤란환자들중, 설골상부전기자극치료와고식적연하곤란치료를모두받은환자 12명과 2006 년 1월부터 2007 년 6월까지고식적연하곤란치료만을받은환자 12명을대상으로후향적, 짝짓기, 비교대조군분석법을시행하였다. 전기자극치료군은남자 5명, 여자 7명이며나이는 68.0± 16.0세이며발병일로부터치료시작까지기간은 3.6±3.8 개월로다양하였다. 고식적연하곤란치료군은성별, 나이 ( 차이 5세미만 ), 발병일로부터치료시작때까지기간 (1 개월, 1~5 개월, 6개월이상 ) 을서로짝지어해당하는환자들로선택하였다 (Table 1). 뇌졸중연하곤란환자들중인지기능의장애, 피부질환, 기도도관 (T-cannula), 심혈관계 TABLE 1. Characteristics of the patients Electrical stimulation Conventional management Sex Age Diagnosis Time* Age Diagnosis Time* 01 F 74 MCA infarct 01 73 MCA infarct 01 02 F 67 SDH 01 68 Clivus meningioma 01 03 M 72 CR infarct 08 73 MCA infarct 07 04 F 24 SDH 02 28 Craniopharyngioma 02 05 F 73 MCA infarct 01 76 Pontine infarct 01 06 F 69 CR infarct 01 69 PVWM infarct 01 07 M 66 MCA infarct 06 70 Cerebellar infarct 11 08 M 72 MCA infarct 01 72 CR infarct 01 09 F 83 BG ICH 05 86 Pontine infarct 05 10 F 71 IC infarct 14 73 MCA infarct 12 11 M 85 MCA infarct 05 84 Pontine infarct 06 12 M 45 Schwanoma 01 50 Medullar infarct 01 *month. MCA: middle cerebral artery, SDH: subdural hematoma, CR: cerebral, BG: basal ganglia, ICH: intracranial hemorrhage, IC: internal capsule, PVWM: periventricular white matter 질환, 전경부수술과거력이있는사람들은전기자극치료를시행하지않았다. 연하곤란의진단은음식섭취시반사적기침이나젖은목소리등임상적으로연하곤란이의심되는환자들을대상으로비디오투시촬영검사를시행하여확진하였다. 연하곤란평가환자들의연하기능평가는연하곤란임상척도 (clinical dysphagia scale, Appendix 1), 기능적연하곤란척도 (functional dysphagia scale, Appendix 2), 9 American Speech-Language-Hearing Association(ASHA) 척도 (Appendix 3) 10 를이용하였고, 이지표들을치료전, 후로비교하여연하기능의호전여부를분석하였다. 각지표들은환자기록및비디오투시촬영검사후녹화된영상을토대로재활의학과의사 4명이모여결정하였다. 연하곤란임상척도는연하곤란이뇌졸중후흔하게발생하며흡인성폐렴, 영양장애, 패혈증등심각한합병증으로기능회복의지연은물론사망까지도초래할수있다는임상적중요성에의거하여, 뇌졸중환자에서발생한연하곤란을선별할목적으로제안되었다. 임상증상, 뇌병변위치및이학적검진소견에따라가중치를두어 0~100 점으로분류하였다. 기능적연하곤란척도 9 는비디오투시촬영검사를토대로흡인여부, 잔류음식의양등여러지표들을항목마다가중치를달리하여 100 점만점으로점수화한것으로연하곤란치료의효과를정량적으로판정하는데유용하게사용되고있다. 비디오투시촬영검사는물 2 cc, 요플레, 푸딩, 죽, 밥을각각 2회씩먹인후에나타나는소견을녹화하여분석하였다. ASHA 척도는환자의식이정도와독립정도를 1에서 7 까지 7단계로단순하게표현한척도로서환자의기능상태를직관적으로표현하는데도움이되어실제미국언어청각학회에서많이쓰이고있다. 10 연하곤란치료연하곤란의고식적치료는얼음삼키기 (ice cube training), 두번삼키기 (double swallowing), 멘델슨기법 (Mendelsohn maneuver), 인두부온도자극 (pharyngeal tactile stimulation) 등으로구성되었으며, 매일하루 30분씩훈련된작업치료사에의해치료를받았다. 설골상부전기자극치료는현재국내에서시행되고있는 StimPlus DP-200 (Cybermedic Corp.) 을이용하여훈련된작업치료사가매일하루 20분씩자극하였다. 양채널방식으로자극하였으며, 자극지표는 60 Hz, 500 μsec, biphasic 파형으로정하였다. 후두근경련을방지하기위하여 www.stroke.or.kr 135
Electrical Stimulation on Suprahyoid Muscles 1초간자극후 1초간휴지기를두는간헐적자극을시행하였다. 자극부위는양측하악골각에서턱끝에이르는선의중간점과, 턱끝에서설골의양끝을잇는선의중간점으로각각정하였다 (Figure 1). 전기자극은 3 ma부터시작하여 1 ma 간격으로늘여가면서환자가참을수있는최대한의강도까지자극하였다. 치료도중심한통증을느끼거나어지럼증을호소하는경우에는즉시치료를중단하도록하였다. 전류자극의세기는 5~12 ma까지개개인에따라편차가심하였으며설골상부전기자극을가하는동안일시적인불편감외에는별다른부작용은관찰되지않았다. 결과 초기연하곤란중증도비교초기연하곤란임상척도는전기자극치료군이 14.8± 16.9, 고식적연하곤란치료군이 20.8±13.3 으로두군간의미있는차이를보이지않았으며 (P>0.05) 기능적연하곤란임상척도도각각 28.4±12.7, 26.9±12.7 로군간차이는관찰되지않았다 (P>0.05). 초기 ASHA 척도는전기자극치료군이 3.7±1.7, 고식적연하곤란치료군이 3.8±2.0 으로군간차이는관찰되지않았다 (P>0.05). 통계방법전기자극치료군과고식적연하곤란치료군간초기연하곤란중증도의차이를비교하기위하여연하곤란임상척도, 기능적연하곤란척도에대하여 Mann-Whitney U 검정을시행하였고, ASHA 척도에대하여 χ 2 검정을시행하였다. 전기자극치료군및고식적연하곤란치료군에서치료전, 후연하곤란임상척도, 기능적연하곤란척도의변화에대하여 Wilcoxon 순위합검정을시행하였고, 군간변화에대한차이를비교하기위하여 Mann-Whitney U의검정을시행하였다. 두군간치료전, 후 ASHA 척도의호전여부에대한차이를보기위하여 χ 2 검정을시행하였다. 모든통계에대하여 α-error 는 0.05 로정하였다. 연하곤란임상척도전기자극치료군에서는치료전 14.8±16.9 에서치료후 10.3±6.7 로호전되었고고식적연하곤란치료군에서도치료전 20.8±13.3에서치료후 13.2±9.2로호전되어통계적으로두군모두유의한차이를보였으며 (P<0.05) (Figure 2), 두군간치료효과의차이는통계적으로유의하지않았다 (P>0.05)(Table 2). 기능적연하곤란척도전기자극치료군에서는치료전 28.4±12.7 에서치료후 23.8±14.8 로, 고식적연하곤란치료군에서는치료전 26.9 ±12.7에서치료후 18.9±14.0 으로호전되는소견을보였고 (P<0.05)(Figure 3), 두군간통계적으로유의한차이는관찰되지않았다 (P>0.05)(Table 2). 기능적연하곤란척도중인두부에해당하는부분만따로분석하였을때 (Triggering of pharyngeal swallow 이하, Appendix 2) 전기자극치료군에서는치료전 20.7±7.9 에서치료후 14.0± 9.8 로, 고식적연하곤란치료군에서는치료전 21.5±9.1에서 16.8±13.1 로호전되어전기자극치료군이고식적연하곤란치료군보다더욱호전되는것을보였다 (P<0.05). FIGURE 1. Location of electrodes during electrical stimulation of suprahyoid muscles. American Speech-Language-Hearing Association 척도전기자극치료군에서는 9명의환자들 (75%) 에서 ASHA 척도의호전을보였으며, 고식적연하곤란치료군에서는 6명의환자들 (50%) 에서만 ASHA 척도의호전을보여두군간통계적으로유의한차이가관찰되었다 (P<0.05)(Table 3). TABLE 2. Change of clinical and functional dysphagia scale in electrical stimulation and conventional management group Electrical stimulation Conventional management Pre Post Pre Post Clinical dysphagia scale 14.8±16.9 10.3±06.7 20.8±13.3 13.2±09.2 Functional dysphagia scale 28.4±12.7 23.8±14.8 26.9±12.7 18.9±14.0 Pharyngeal portion in the functional dysphagia scale 20.7±07.9 14.0±09.8 21.5±09.1 16.8±13.1 136 Korean J Stroke 2007;9:134-141
Jung Hwan Kim, et al. 60 60 50 50 40 40 30 30 20 20 10 10 FIGURE 2. Changes of clinical dysphagia scale in the electrical stimulation and the conventional management groups. 0 Pre Post Electrical stimulation 0 Pre Post Conventional management 100 100 90 90 80 80 70 70 60 60 50 50 40 40 30 30 20 20 10 10 FIGURE 3. Changes of functional dysphagia scale in the electrical stimulation and the conventional management groups. 0 Pre Post Electrical stimulation 0 Pre Post Conventional management 고찰 이번연구결과에서기존에알려진연하곤란치료에설골상부전기자극치료를추가시기존연하곤란치료만시행하였을때보다연하곤란임상척도, 기능적연하곤란척도에서는추가적인호전이관찰되지않았으나, 인두부에해당하는항목들의기능적연하곤란척도와 ASHA 척도는추가적인호전을보였다. 이번연구는설골상부전기자극치료를받았던환자들과이들개개인의특성과비슷한과거환자들의자료를비교분석하는방법을택하였다. 이는연하곤란환자들의나이, 병변의위치, 발병일부터치료일까지의기간및초기연하장애정도가다양하여위자극 (sham stimulation) 대조군을정하기가어렵고, 인두부에감각역치이하의전류를가하게되면환자들이알게되고, 감각역치이상의전류를가하게되면연하반사의유발에따른전기자극치료효과가발생하게되어이중맹검기법을사용하기가어렵기때문이었다. 이번연구에서는고식적연하곤란치료군에서만 3명의뇌간병변환자들이포함되는등두군간병변의위치를동일하게배분하지못하였다. 그러나 Schroeder 등 11 에따르면뇌병변의위치가연하곤란의호전정도에미치는영향은뚜렷치않은것으로알려져있어두군간병변위치의차이는본연구결과에큰영향을미치지는않았을것으로생각된다. 이번연구결과는다른척도들과는달리 ASHA 척도에서더좋은결과가나왔는데, 이는연하곤란임상척도와기능적연하곤란척도가구강기의연하장애도많이반영하여인두부전기자극치료의추가효과가희석된것으로생각된다. 환자들의전반적인음식섭취기능은호전되었으나구강기를반영하는부분에서중추성안면신경마비등으로인하여입술닫힘 (lip closure) 이나식괴형성 (bolus formation) 이치료후에도호전이없는경우들이있거나반대로두군모두고식적연하곤란치료에의해구강기를반영하는부분의호전이인두기를반영하는부분의호전을희석시킨경우들이있었기때문이다. 인두부에해당하는항목들만따로분석 www.stroke.or.kr 137
Electrical Stimulation on Suprahyoid Muscles TABLE 3. Change of American Speech-Language-Hearing Association (ASHA) score in electrical stimulation and conventional management group Electrical stimulation Conventional management Pre Post Pre Post 01 5 6 5 5 02 5 7 1 3 03 3 5 3 3 04 6 7 5 6 05 5 7 1 4 06 3 5 5 5 07 5 5 7 6 08 5 7 2 1 09 2 6 6 7 10 1 1 5 5 11 1 6 2 4 12 3 2 4 6 을하였을때인두부전기자극치료의추가효과가나타난점이이를뒷받침한다. 한명의전기자극군환자 (No.12) 에서치료후연하곤란임상척도는호전되었으나 ASHA 척도가 3단계에서 2단계로오히려낮아졌는데이는첫검사당시에는기도흡인이일어나도반사적기침이없었던잠재적흡인이있었으나다음번검사시에는후두개반사가회복되어기도흡인시반사적기침이발생하여이러한상반된결과가나오게되었다. 따라서연하곤란환자들을평가하는데에있어서다양한척도들을사용하여종합적으로평가하는것이중요할것이다. 연하곤란환자들에서전기자극치료시효과여부를보는비교대조군연구는그다지많이시행되지않았다. Blumenfeld 등 2 이나 Freed 등 5 의연구에서는기존의연하곤란치료보다인두부전기자극치료시연하곤란의호전이더큰것으로발표되었고, Ludlow 등 7 은만성뇌졸중환자들에서연하과정중인두부전기자극을가하게되면연하곤란이오히려더악화되는것으로발표하였다. Carnaby-Mann 등 12 은연하재활에있어전기자극치료효과를평가하기위하여메타분석을시행하였고, 비록소수의연구결과들이지만치료효과를확인하였다. 이번연구에서사용한자극위치는설골상부로국한하였으며, 그이유는정상연하시비록갑상설골근의수축으로후두부를상승시켜인두부연하를일으키나, 갑상설골근을전기자극으로수축시키면정상연하시와는달리후두부의움직임보다는설골이아래로끌려내려오기때문이었다. 현재갑상설골근을자극하여연하기능의호전을가져온경우에는실제로근육의수축을유발시킨것이아닌감각신경의자극에따른연하반사의유발로생각된다. 본연구진들은이전 연구 13 에서정상인들을대상으로이번연구에서시행한방법대로전기자극을가하여투시촬영검사를통해설골및후두부가상승하였음을입증하였다. 따라서이번연구에서는실제로설골상부근육을수축시킬정도로최대한의자극을가하여그치료효과를보고자하였다. 설골상부전기자극시발생할수있을부작용으로는피부화상, 통증, 미주신경자극으로인한심혈관계부작용, 고주파수자극에따른후두근경련 (laryngeal spasm) 등이있을수있겠으며, 이번연구에서는일시적인통증외에는어떠한부작용도나타나지않았다. 후두근경련을피하고, 실제로정상연하시설골의운동시간이대략 1초정도발생하는것을고려하여 1초간자극후, 1초간쉬는간헐적인자극을주었다. 현재개발되어널리쓰이고있는 VitalStim (Chattanooga Group, Hixson, TN) 은후두근경련을예방하기위하여 700 μsec 중간에 100 μsec 의휴지기를두는방식을택하였고, 아직후두근경련이보고된적없는것으로알려져있다. 그러나아직이들부작용발생예방을위한자극시생리학적변화들에대한연구는진행되지않았고, 이에대한동물실험등을통한생리학적인연구들이필요할것으로생각된다. 이번연구는후향적과거대조군 (retrospective non-concurrent control) 을사용하여발생할수있는교란변수들을제어하였고, 단일전극위치및단일자극지표를사용하였다. 향후인두부전기자극치료의효과를확립하기위하여무작위동시대조군연구및다양한전극위치, 다양한자극지표들을이용한연구들이진행되어야할것이다. 중심단어 : 설골상부근육 연하곤란 전기자극. REFERENCES 1. Martino R, Foley N, Bhogal S, Diamant N, Speechley M, Teasell R. Dysphagia after stroke: incidence, diagnosis, and pulmonary complications. Stroke 2005;36:2756-2763. 2. Blumenfeld L, Hahn Y, Lepage A, Leonard R, Belafsky PC. Transcutaneous electrical stimulation versus traditional dysphagia therapy: a nonconcurrent cohort study. Otolaryngol Head Neck Surg 2006;135: 754-757. 3. Chetney R, Waro K. A new home health approach to swallowing disorders. Home Healthc Nurse 2004;22:703-707; quiz 708-709. 4. Crary MA, Carnaby-Mann GD, Faunce A. Electrical stimulation therapy for dysphagia: descriptive results of two surveys. Dysphagia 2007;22:165-173. 5. Freed ML, Freed L, Chatburn RL, Christian M. Electrical stimulation for swallowing disorders caused by stroke. Respir Care 2001;46:466-474. 6. Oh BM, Kim DY, Paik NJ. Recovery of swallowing function is accompanied by the expansion of the cortical map. Int J Neurosci 2007;117: 1215-1227. 7. Ludlow CL, Humbert I, Saxon K, Poletto C, Sonies B, Crujido L. Effects of surface electrical stimulation both at rest and during swallowing in chronic pharyngeal Dysphagia. Dysphagia 2007;22:1-10. 138 Korean J Stroke 2007;9:134-141
Jung Hwan Kim, et al. 8. Burnett TA, Mann EA, Cornell SA, Ludlow CL. Laryngeal elevation achieved by neuromuscular stimulation at rest. J Appl Physiol 2003;94: 128-134. 9. Han TR, Paik NJ, Park JW. Quantifying swallowing function after stroke: a functional dysphagia scale based on videofluoroscopic studies. Arch Phys Med Rehabil 2001;82:677-682. 10. Wesling M, Brady S, Jensen M, Nickell M, Statkus D, Escobar N. Dysphagia outcomes in patients with brain tumors undergoing inpatient rehabilitation. Dysphagia 2003;18:203-210. 11. Schroeder MF, Daniels SK, McClain M, Corey DM, Foundas AL. Clinical and cognitive predictors of swallowing recovery in stroke. J Rehabil Res Dev 2006;43:301-310. 12. Carnaby-Mann GD, Crary MA. Examining the evidence on neuromuscular electrical stimulation for swallowing: a meta-analysis. Arch Otolaryngol Head Neck Surg 2007;133:564-571. 13. Kim SJ, Lee KJ, Jeong HC, Han TR. Effect of surface electrical stimulation of suprahyoid muscles on the movements of the hyo-laryngeal complex. Neuromodulation 2007 in submission;2007. www.stroke.or.kr 139
Electrical Stimulation on Suprahyoid Muscles 부 록 1. Clinical Dysphagia Scale 2. Functional Dysphagia Scale Location Non-stem lesion 000 Stem lesion 005 T-cannula No 000 Yes 025 Aspiration No 000 Yes 010 Lip sealing Intact 000 Inadequate 002 None 004 Chewing and mastication Intact 000 Inadequate 004 None 008 Tongue protrusion Intact 000 Inadequate 004 None 008 Laryngeal elevation Intact 000 Inadequate 005 None 010 Reflex coughing No 000 Yes 030 Total 100 Lip closure Intact 000 Inadequate 005 None 015 Bolus formation Intact 000 Inadequate 003 None 006 Residue in the oral cavity None 000 10% 002 10-50% 004 >50% 006 Oral transit time 1.5 sec 000 >1.5 sec 006 Triggering of pharyngeal swallow Normal 000 Delayed 010 Laryngeal elevation and epiglottic Normal 000 closure Reduced 012 Nasal penetration None 000 10% 004 0-50% 008 >50% 012 Residue in the valleculae None 000 10% 004 10-50% 008 >50% 012 Residue in the pyriform sinuses None 000 10% 004 10-50% 008 >50% 012 Coating of pharyngeal wall after No 000 swallow Yes 010 Pharyngeal transit time 1.0 sec 000 >1.0 sec 004 Total 100 140 Korean Journal of Stroke 2007;9:134-141
Jung Hwan Kim, et al. 3. American Speech-Language-Hearing Association National Outcome Measurement System (ASHA NOMS) Swallowing Level Scale Level 1 Individual is not able to swallow anything safely by mouth. All nutrition and hydration is received through nonoral means (e.g., NG tube, PEG). Level 2 Individual is not able to swallow safely by mouth for nutrition and hydration but may take some consistency with consistent maximal cues in therapy only. Alternative method of feeding is required. Level 3 Alternative method of feeding required as individual takes less than 50% of nutrition and hydration by mouth, and/or swallowing is safe with consistent use of moderate cues to use compensatory strategies and/or requires maximum diet restrictions. Level 4 Swallowing is safe but usually requires moderate cues to use compensatory strategies, and/or individual has moderate diet restrictions and/or still requires tube feedings and/or oral supplements Level 5 Swallowing is safe with minimal diet restrictions and/or occasionally requires minimal cueing to use compensatory strategies. May occasionally self cue. All nutrition and hydration needs are met by mouth at mealtime Level 6 Swallowing is safe and individual eats and drinks independently and may rarely require minimal cueing. Usually self cues when difficulty occurs. May need to avoid specific food items (e.g., popcorn and nuts), or requires additional time (due to dysphagia). Level 7 Individual s ability to eat independently is not limited by swallow function. Swallowing would be safe and efficient for all consistencies. Compensatory strategies are effectively used when needed. NG: nasogastric www.stroke.or.kr 141