KISEP Head and Neck Korean J Otolaryngol 1999;42:762-9 편도적출술과편도및아데노이드적출술후음성변화에관한음성학적및영상학적연구 이종환 1 구교준 1 구한얼 1 김유찬 1 구수권 1 이상화 1 왕수건 2 김학진 3 양병곤 4 An Acoustic and Radiologic Study on Voice Change after Tonsillectomy and Adenotonsillectomy Jong Hwan Lee, MD 1, Gyo Jun Koo, MD 1, Han Eol Koo, MD 1, Yu Chan Kim, MD 1, Soo Kweon Koo, MD 1, Sang Hwa Lee, MD 1, Soo Guen Wang, MD 2, Hak Jin Kim, MD 3 and Byung Gon Yang, PhD 4 1 Department of Otolaryngology, St. Benedict Hospital, Pusan, 2 Department of Otorhinolaryngology, 3 Diagnostic Radiology, College of Medicine, Pusan National University, Pusan, 4 Department of English, College of Humanities, Dongeui University, Pusan, Korea ABSTRACT Background and ObjectivesSome patients who have undergone tonsillectomy complain of voice change, but few studies for the mechanism of voice change were found. To solve this problem, study of voice change after tonsillectomy and adenotonsillectomy was done. Materials and MethodsWe analyzed voice change of 22 patients who underwent tonsillectomy and 15 patients who underwent adenotonsillectomy at CSL computerized speech laboratory, St. Benedict Hospital. With the measured cross sectional area of vocal tract and its length from the glottis on MR images, we presented the change of cross sectional area schematically after tonsillectomy. ResultsAcoustically, the frequencies of the second formant of e and i increased and that of the first formant of u decreased significantly after tonsillectomy and the frequency of the second formant of o and those of the second and third formants of i and u increased significantly after adenotonsillectomy. It was also showed acoustically that the formant bandwidths of a and hana after tonsillectomy and those of e and hanaafter adenotonsillectomy increased due to nasalization. Anatomically, it was showed that the cross sectional area of oropharyngeal cavity increased and coupling effect of vocal tract happened after tonsillectomy. ConclusionThis study showed that acoustic characteristics and vocal tract shapes of the patients did change following tonsillectomy and adenotonsillectomy. It is imperative that we explain to patients about the postoperative voice change. Research should also be done to find ways to induce better voice changes following the operations. Korean J Otolaryngol 1999;42:762-9 KEY WORDSTonsillectomy Adenotonsillectomy CSL Vocal tract MRI. 762
수술방법 음향학적분석 자기공명영상을이용한성도촬영 성도외곽추출 (Extraction of vocal tract boundary) Table 1. Age and sex distribution Sex Male Female Age T T & A T T A Total 10 1 5 1 5 12 11 20 6 4 6 1 17 21 30 3 0 3 0 6 31 40 2 0 0 0 2 Total 12 9 10 6 37 TTonsillectomy AAdenoidectomy Fig. 1. A coordinate framework used to measure the normal subject s vocal tract shape during vowel production. 763
자기공명영상을이용한성도의단면적계산 (Cross sectional area calculation from MR images) 지각실험 (Perceptual analysis) Fig. 3. Cross sectional area displayed by FORMFREK from a pretonsillectomy patient producing voweli. Fig. 4. Cross sectional area displayed by FORMFREK from a post-tonsillectomy patient producing vowel /i/. Table 2. The protocol of perceptual analysis Perception of Perception of nasal Score Score vowel consonant 0 No difference 0 No difference Fig. 2. A boundary of mid-sagittal vocal tract and its central 1 Little difference 1 Little difference line a and calculation of its cross sectional area b of section 2 Little difference 2 Severely nasalized 1. 764 Korean J Otolaryngol 1999;42:762-9
이종환 외 포만트의 주파수가 감소하였다(p<0.01). 편도적출술후에는 모음 /a/의 제2포만트의 대폭이(p<0.05), 편도 및 아데노이드적출술후에는 모음 /e/의 제2포만트의 대 폭이(p<0.05) 통계적으로 유의하게 증가되어 비음화가 됨을 알 수 있었다. 편도적출술후에는 비강자음 하나 의 제2포만트의 대폭 이(p<0.05), 편도 및 아데노이드적출술후에는 비강자음 하 나 의 제2포만트의 대폭(p<0.01)과 치킨 의 제3포만트 의 대폭이(p<0.05) 통계적으로 유의하게 증가하여 자연스러 운 비음화가 됨을 알 수 있었다. 이상의 음향학적 분석의 결 과는 다음과 같다(Table 3). Table 3. Results of acousic analysis Operation Formant frequency of vowels Tonsillectomy /u/* /e/*, /i/*, /u/* /i/* T&A /i/**, /u/* /i/**, /u/* Formant frequency of nasal consonants Tonsillectomy T&A /hana/*,/ŋga/* /t ikin/* Bandwidth of formant Tonsillectomy /a/*, /hana/* T&A /e/*, /hana/** /t ikin/* T Tonsillectomy, A Adenoidectomy, no significant change * p-value<0.05, ** p-value<0.01, paired t-test Fig. 5. MR images and their diagrams of pretonsillectomy patient s vocal tract during vowel phonation. Arrow indicates tonsil. 765
편도적출술과 편도 및 아데노이드적출술후 음성변화에 관한 음성학적 및 영상학적 연구 술전 술후 성도의 자기공명영상의 변화 면적의 많은 부분을 차지하게 되어 변화가 심하다. 커플링 편도적출술후의 변화로는 편도제거로 인하여 인두강의 효과(coupling effect)의 경우 편도 뿐만 아니라 비강을 막 면적이 넓어지고 인두강의 좁힘점의 일부로 작용하던 편도 고 있는 아데노이드가 제거되어 더욱 심한 변화가 일어난다 가 제거되어 인두강의 좁힘점이 줄어들며 인두강과 비강을 (Fig. 8). 분리시키던 편도가 제거되어 커플링효과(coupling effect, 비강이 성도의 공명강과 합쳐짐)가 생기며 편도적출술로 인 하여 인두강의 수축이 일어나고 인두강의 길이가 짧아진다 고 추측된다(Figs. 5, 6 and 7). 성도 단면적의 변화 자기공명영상에서 구인강은 각 예에서 3분절(slices)씩 차지하여 총 9분절이었으며 9분절의 술후 단면적 변화를 편도 및 아데노이드적출술후의 변화로는 일반적으로 성인 Wilcoxon signed-rank test로 처리하였다. 모든 예에서 에 국한되어 시행되는 편도적출술에 비해 편도 및 아데노이 술후 단면적이 통계적으로 의미있게 증가하였다(Table 4). 드 적출술은 소아에서 시행되고 따라서 상대적으로 인두강 Fig. 6. MR images and their diagrams of post-tonsillectomy patient s vocal tract during vowel phonation. 766 Korean J Otolaryngol 1999;42:762-9
Fig 7. Vocal tract change after tonsillectomy. Fig. 8. Vocal tract change after adenotonsillectomy. The syol * represents that more coupling effect occurred in case of adenotonillectomy. Table 4. The changes of cross sectional area at oropharyngeal cavity with sustained vowel after tonsillectomycm 2 Mean s.d. Mean s.d. a i u Pre. Post Pre Post Pre Post 24.5 44.6 * 49.1 56.0 * 22.1 38.5 * 9.5 21.4 35.0 33.3 17.4 24.8 e o Pre. Post Pre Post Pre Post 32.2 61.1* 15.4 32.5 * 16.5 35.9 * 28.2 41.0 10.0 15.2 8.5 16.0 Mean : mean cross sectional area * : p-value 0.05,Wilcoxon signed-rank test s.d : standard deviation of cross sectional area Table 5. Result of perceptual analysis Score Perception of vowel Perception of nasal consonant 0 1768% 1560% 1 832% 728% 2 0 0% 312% 767
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