RESIN 취급 주물공장 근로자들의 호흡기 건강에 관한 연구

최정근,이창옥,백도명,최병순,신용철,정호근,Choi, Jung-Keun,Rhee, Chang-Ok,Paek, Do-Myung,Choi, Byung-Soon,Shin, Yong-Chul,Chung, Ho-Keun 대한예방의학회 1994 Journal of Preventive Medicine and Public Health Vol.27 No.2

The effects of resin on the respiratory health have been investigated in 309 workers from four iron and steel foundries and the results compared with those from 122 workers who were not significantly exposed to resin gas and silica dust at the same industries. Phenol-formaldehyde resin was used in the core making and molding processes and workers were exposed to their decomposition products as well as to silica dust containing particulates. The subjects were grouped according to formaldehyde, dust and other gas exposures, and smoking habits were considered also in thi analysis. Standardized respiratory symptom questionnaire was administered by trained interviewers. Chest radiograph, pulmonary funtion tests, and methacholine challenge tests were done. Environmental measurements at the breathing zone were carried out to determine levels of formaldehyde, respiable dust and total dust. Foundry workers had a higher prevalence of symptoms of chronic bronchitis with chronic phlegm and chronic cough when exposed to dust. Exposure to gas was significantly associated with lowered $FEV_1$ and obstructive pulmonary function changes. Exposure to formaldehyde and phenol gas was associated with wheezing symptom among workers, but $FEV_1$ changes after methacholine challenge were not significantly different among different exposure groups. When asthma was defined as the presence of bronchial hyperreactivity with more than 20% decrease in $FEV_1$ after methacholine challenge, 17 workers out of 222 tested had asthma. Fewer asthmatic welters were found among groups exposed to formaldehyde, gas and dust, which indicates a healthy worker effects ill a cross-sectional study. The concentration of formaldehyde gas ranged from 0.24 to 0.43 ppm among studied foundries. The authors conclude that formaldehyde and phenol gas from combusted resin is probably the cause of asthmatic symptoms and also a selection force of those with higher bronchial reactivity away from exposures.

Statistical analyses in an occupational health study

Jung Keun Choi(최정근),Mi A Son(손미아),Do Myung Paek(백도명) 한국통계학회 1993 응용통계연구 Vol.6 No.2

산업보건연구의 통계학적 분석은 작업환경측정에 대한 평가방법과 산업보건에 특유한 혼란변수의 통제 등 건강상태와의 연관성을 분석하는 평가방법에 있어 아른 보건통계분야와 구별되는 특성을 지니고 있다. 본 논문에서는 주물공장 근로자들의 호흡기 건강상태와 작업환경에서 폭로되는 유해물질에 대한 조사를 통하여 산업보건연구에 사용되는 통계학적 분석에 대한 기술을 하였다. 조사된 환경측정결과의 일부는 허용폭로기준을 초과하고 있었는 바, 폭로기준의 준수여부를 판정하기 위하여 작업환경측정결과와 그들의 대수변환치들로 부터 얻은 산술평균과 대수평균들이 폭로기준과 다른지에 대한 t-검정을 실시하였다.환경측정을 비롯한 위험요인들과 그들로 인한 건강상태와의 관계 분석을 위해, 범주적 건강측정 변수인 경우에는 χ-square 검정과 다변량 logistic분석을 시행하였고, 연속적 변수인 경우에는 다변량 회귀분석을 시행하였다. 작업환경내의 오염물질의 농도는 그 측정장소와 측정시점에 따라 매우 가변적이다. 이러한 작업환경의 측정결과를 평가하는데 있어 사용될 수 있는 서로 다른 여러 지수들의 장단점과 가변적 측정결과들로 인한 오차를 보정할 수 있는 통계학적 분석 방법에 대한 논의를 하였다. 본 조사의 폐기능검사 결과는 직업에서 폭로되는 정도와 아무 연관성을 보이고 있지 않은 바, 이는 건강한 근로자 효과에 기인한 것으로 추정되고 있다. 이러한 건강한 근로자 효과를 비롯한 측정시점에 따라 변화하는 혼란변수를 보정하기 위한 통계적 분석 방법이 논의 되었다. 산업보건 연구에서 기본적으로 사용될 수 있는 전국적 생정통계와 같이 광범위하며 쉽게 비교되는 외부 대조군 내지는 질병의 예측기대치에 대한 통계가 한국의 경우에는 아직 없다. 이러한 경우, 그 분석의 범위가 매우 제한되어 있으나, 문제되는 질병 내지는 임상검사결과가 다른 일반적 질환과 비교하여 차지하는 비율을 서로 다른 집단간에 비교함으로써 서로 다른 작업환경에 폭로되는 집단들에 대한 통계학적 분석을 시도할 수 있다. 현재 한국에서는 일반검진과 특수검진이 정규적으로 실시되고 있으며, 이러한 검진결과에 대한 체계적 통계학적 분석이 앞으로 필요할 것으로 기대된다. The health status of workers in a foundry was analyzed in a study which consisted of evaluations of respiratory health together with environmental measurements. The results from environmental measurements showed values exceeding permissible exposure limits. A t-test was done with log transformed and untransformed data to examine the statistical significance for the noncompliance with exposure standards. For the analysis of categorical health outcomes, χ-square test with 2×2 tables and logistic regression analysis were employed. For continuous variables, multiple linear regression was done against assessed risk factors. Pros and cons of different parameters in the compliance (or noncompliance) testing were presented. Respiratory function did not show any relation with occupational exposures, which may be due to the healthy worker effects. Strategies for controlling time dependent covariates were discussed in relation to the healthy worker effect. The scope of statistical analysis in occupational health studies is still limited in Korea without a suitable external comparison group such as credible vital statistics for the whole nation. Internal comparisons between different exposure status often result in unstable estimates of effect, and proportional morbidity study is discussed as an alternative potential research tool.

한국인의 정상 폐활량 예측치

최정근 ( Jung Keun Choi ),백도명 ( Do Myung Paek ),이정오 ( Jeoung Oh Lee ) 대한결핵 및 호흡기학회 2005 Tuberculosis and Respiratory Diseases Vol.58 No.3

연구배경 : 우리나라 국민을 대상으로 실시한 폐활량검사의 판정과 해석은 우리나라 국민을 대상으로 구한 폐활량 예측식이 사용되어야 한다. 그 동안 외국인을 대상으로 구한 폐활량 예측치가 사용되어 오류가 있었다. 본 연구에서는 전 국민을 대상으로 대표성 있고 신뢰할 수 있는 노력성 폐활량과 일초간 노력성 폐활량, 6초간 노력성 폐활량, 일초율에 대한 정상 예측식을 개발하고자 하였다. 연구방법 : 전 국민을 대상으로 층화표본 추출법을 사용하여 조사대상을 선정 Background : Spirometry should be compared with the normal predictive values obtained from the same population using the same procedures, because different ethnicity and different procedures are known to influence the spirometry results. This study was pe

소음 특수건강진단 자료를 이용한 순음청력검사 평가

김양호,최정근,박정선,문영한,김규상,Kim, Yang-Ho,Choi, Jung-Keun,Park, Jung-Sun,Moon, Young-Han,Kim, Kyoo-Sang 대한예방의학회 1999 예방의학회지 Vol.32 No.1

이 연구는 특수건강진단기관의 소음성 난청 진단결과의 유소견자$(D_1)$와 요관찰자(C)를 하나의 평가 지표로 설정하여, 첫째 소음 특수건강진단 결과 소음성 난청의 실태 파악, 둘째 소음성 난청 요관찰 자의 청력장애 평가, 셋째 정력장애 정도 에 따른 각 주파수 영역별 기도순음청력 검사 결과를 통해 청력손실의 정도를 파악하고 이의 판정기준에 따른 진단의 적정성을 검토하고자 하였다. 1. 1994년 l월부터 12월까지의 73개 특수건강진단기관의 특수건강진단 실시 사업장은 27,347개이며 이중 소음 특수 건강진단 설시 사업장은 16,388개(59.9%)이었으며, 전체 특수건강진단 수진 근로자는 731,029명이며 이중 소음 특수 건강진단 수진 근로자는 343,457명 (47.0%)이었다. 소음성 난청 요관찰자는 38,058명, 소음성 난청 유소견자는 1,358 명으로 소음성 난청 요관찰률은 11.1%, 유소견율은 0.44%이었다. 지역에 따라 소음성 난청 요관찰률의 차이를 보여주며 판정기준의 적용에 따른 기도순음 청력평균손실치가 일부 적정하게 판단되지 못하였음을 보여 주었다. 2. ISO 기준의 3분법에 의한 청력 평가시 97%가 경도난청 이하였으며, 회화음 역에서의 4분법에 비해 거의 비슷하였으나 약간 정상역이 많았고, 고음역을 포함하여 평가하는 4분법과 6분법의 적용시 정상자의 경도난청으로의 가능성이 높다고 볼 수 있어 청력평가시 평가방법의 적용에 따라 내재적인 판별능의 차이를 보여준다고 볼 수 있다. 3. 우측귀의 청력역치를 ISO 기준에 의해 평가한 후 양귀의 청력역치의 분포 및 차이를 보면, 우측귀의 평균역치(표준편차)가 20.54(9.56) dB, 좌측귀의 평균역치가 20.54(9.57) dB로 좌측귀의 평균역치가 우측보다 높았다. 양귀의 청력이 75.4%에서 정상역이었으며, 21,562명 (90.6%)의 양귀 청력역치 차이의 범위가 10dB이내였다. 4. 소음성 난청 요관찰자의 회화음역에 속하는 500, 1,000 및 2,000 Hz에서의 기도청력역치를 산술평균으로 하여 구하는 3분법의 청력손실도(표준편차)를 주파수 별로 보면, 우측귀에서 500 Hz 21.08(10.23), 1,000 Hz 18.44(10.01), 2,000 Hz 22.09(13.46), 4,000 Hz 52.36(16.38) dB이었다. 평균청력손실도를 10 dB 간격으로 구분한 후 각각의 주파수별 청력역치를 살펴보면, 정상역인 20 dB미만에서 고음역인 4,000 Hz에서 회화음역인 500, 1,000 및 2,000 Hz에서 보다 평균 30-40 dB 이상의 역치를 보이는 $C_5-dip$ 현상을 특징적으로 보였다. 평균정력손질이 증가함에 따라 4,000 Hz에서의 역치 증가 현상이 점차적으로 감소하다 평균청력손실이 50 dB 이상에서는 10dB 내외의 차이만을 나타내었다. 이상과 같이 소음성 난청 요관찰자에 대한 분석에서 소음성 난청의 평가방법 에 따른 실태와 의미, 소음에 의한 조기청력손실의 특정과 소음성 난청의 판정기준에 따른 진단의 적정성을 확인할 수 있었으며, 소음성 난청 요관찰자에 대한 관리의 필요성을 제언할 수 있겠다. Objectives. This study was carried out to evaluate hearing impairment judgement and to investigate the differences in various diagnostic criteria for noise-induced hearing loss (NIHL) among workers who required for close observation (C). Methods. Out of 731,029 workers who had taken the specific periodic health examination in 1994, we used the audiometric data on 37,999 workers (C) eliminating the employees who had previous otologic problems. Many investigators have being using different criteria for the evaluation of hearing impairment. In this study, we used the criteria of early (1989-1994), current, compensation for NIHL in Korea, 2-, 3-, 4-divided classification and hearing loss at 4,000 Hz and compared the evaluation results. Results. The prevalences of C and workers who had occupational disease $(D_1)$ diagnosed for NIHL were 11.1 % and 0.44 %. There were significant difference in the prevalences of C and $D_1$, depending on different province of Korea. Pure tone averages (PTAs) were not appropriately applied in their evaluation 97% of workers whom we studied on were below the level of mild hearing loss judged by ISO standard. However, there were wide variations in the prevalence rate of mild hearing loss by diagnostic criteria. Thus, there were different judgements in determining the degree of NIHL depending on which diagnostic criteria were utilized. PTAs were found 20.54 (Rt) and 20.74 (Lt) when the method of 3-divided classification was applied for audiometric data. The degree of hearing impairment of the left ear was more severe than that of right ear. The prevalence of normal hearing threshold below 20 dB was 75.4% and the range of difference in both ear was below 10 dB. Right sided hearing threshold levels were 21.08 dB (500 Hz), 18.44 dB (1,000 Hz), 22.09 (2,000 Hz) and 52.36 dB (4,000 Hz). There was typical high frequency loss (C5-dip at 4,000 Hz) above 30 - 40 dB in normal hearing level. The increasing trend in hearing threshold level was gradually decreased by the increase of PTAs. The difference between PTAs and threshold at 4,000 Hz was about 10 dB. Conclusions. We could found that PTAs in the previous examination were not appropriately evaluated. This study revealed that they did not use unique criteria for managing the workers of NIHL. For the prevention of NIHL, it was found that the quality control on diagnosis and comprehensive management program were required, especially for those of hearing loss (C).

우리나라의 신체장애평가법에 관한 비교연구 - 신체장해등급법, McBride법, 미국의학협회 (AMA)기준법을 중심으로 -

이창옥,최정근,손미아,문옥륜,Rhee, Chang-Ok,Choi, Jung-Keun,Son, Mi-A,Moon, Ok-Ryun 대한예방의학회 1994 예방의학회지 Vol.27 No.3

In this study, literature review was done to examine and compare the current status and problems of different evaluation approaches toward permanent impairment in Korea. Alternatives and improvements in the current approaches in Korea were suggested. Series of cases were also examined to compare different approaches applied to the real cases, using 105 cases from a hospital data and another 207 cases from a insurance company data. The main findings of the literature review are as follows; 1. The current evaluation methods of permanent impairment in Korea are grouped into two categories, grading and rating. Gradings of impairments are expressly specified in 17 various statutes. 2. In Grading methods, the rigid system of 74 different grades has been adopted uniformally for the convenience of administration, which may not be, appropriate or valid from medical and scientifical aspect. 3. The adventage of McBride method is assessment of occupational disability rate. However the classified compensable occupations are only 280 and limited to manufacturing industries in 1960s'of U.S.A., which is not appropriate to current Korean circumstances. Especially, the job list does not include managerial officers or mental workers. 4. AMA Guides is the scientific and reasonable method for the assessment of physical impairment rate. However compensation and reparation of impairment case is difficult because this method cannot assess the disability rate according to occupation, age, etc. The results of cases comparative study are as follows: 5. The physical Impairment could be compared in 167 out of total 312 cases, and for the cases of complex impairment, McBride method underestimate physical impairment rate compared with AM A method. 6. When disability late was assessed, occupation was considered the compensation of only 85 cases, and age was used in only 21 cases. This was because occupation and age compensation in McBride method are unreasonable. 7. The most Ideal alternative is to assess physical impairment according to AMA method and then to develop a compensation method appropriate for the circumstances of Korea society.

유리섬유 제조업체 근로자의 건강장해

이세휘,김규상,최정근,김양호,강성규,최경숙,문영한,Lee, Se-Wi,Kim, Kyoo-Sang,Choi, Jung-Keun,Kim, Yang-Ho,Kang, Seong-Kyu,Choi, Kyuong-Suk,Moon, Young-Hahn 대한예방의학회 1996 예방의학회지 Vol.29 No.2

The industrial use of MMMF(man-made mineral fibers), has been increasing, particularly since the banning of most asbestos products. Fibrous minerals can cause health abnormalities currently associated with occupational exposure to glass fiber. This study was conducted to evaluate health risks of glass fiber manufactory workers within the country. We examined questionaries, physical examination including auscultation, chest x-ray, pulmonary function test for 488 male workers, to go through their dermal itching symptoms and respiratory evaluation. we had the results as follows. 1. In 45% of the workers itching had been expressed at their entrance. At that time we was investigating, 18.5% had itching, and most of them complained it when they fall asleep and night. The Sequent itching site is waist and groin, upper and lower extremity in order, and it had been expressed mainly during summer and winter. 2. As the results of ventilatory functions test, 6.0% were obstructive type, 1.0% were restrictive type. So, glass fiber exposures should be controlled or elimination by protective devices in the workplace. 3. The means of FVC, $FEV_1,\;FEV_1%$ were in normal range. As the comparison of ventilatory functions by age groups, MMF was decreased significantly for the group, 50 years old and more than other groups. And the comparison by the serving periods at glass fiber producing factory, MMF was decreased for the workers had worked for $11\sim15$ years. Therefore, MMF be more sensitive index in the evaluation of ventilatory impairments caused by glass fiber workers.

중수골 두부에 발생한 관절내 골연골종 - 1례 보고-

이기행,정창훈,문찬웅,김형민,최정근,김영실,김윤수,Lee, Kee-Haeng,Jeong, Chan-Woong,Moon, Chan-Woong,Kim, Hyoung-Min,Choi, Jung-Keun,Kim, Young-Sill,Kim, Youn-Soo 대한근골격종양학회 2004 대한골관절종양학회지 Vol.10 No.2

골연골종은 가장 흔한 양성골종양으로 대부분 장관골의 골간단에 주로 발생한다. 수부에 발생하는 골연골종은 드물며 그 중 관절내 골연골종은 매우 드문 것으로 되어 있다. 저자들은 53세 여자 환자에서 제 3 중수골 두부에 발생된 관절내 골연종을 보고하고자 한다. 적출된 종물은 $10{\times}8{\times}5$ mm 크기로 명확한 연골모를 가지고 있었다. The osteochondroma is the most common benign bone tumor which arise in the metaphyseal or metaphysiodiaphyseal portion of long bone. Osteochondroma is rare in hand and extremely rare in the intraarticular location of the hand. We report a case of intraarticular osteochondroma which occurred at the third metacarpal head of the hand in a 53 year old female patient. The size of the excised mass was $10{\times}8{\times}5$ mm with definite cartilage cap.

Isocyanates 폭로 근로자들의 기관지 과민성

최경숙,김규상,최병순,최정근,이세휘,문영한,Choi, Kyeong-Sook,Kim, Kyoo-Sang,Choi, Byung-Soon,Choi, Jung-Keun,Lee, Se-Hui,Moon, Young-Hahn 대한예방의학회 1996 Journal of Preventive Medicine and Public Health Vol.29 No.1

We studied the association of nonspecific bronchial hyperresponsiveness with general characteristics, exposure concentration, respiratory symptoms, chest x-ray findings, past histories and pulmonary function. We determined bronchial hyperresponsiveness by methacholine challenge test. And we conducted a respiratory symptom questionnaire and performed spirometry on 111 workers occupationally exposed to isocyanates in various industries. About 21.6% of subjects had bronchial hyperresponsiveness. No significant differences were observed between the hyperresponsive and non-responsive group with respect to age, sex, employment period, height, and smoking histories. Cough and breathlessness were significantly associated with the bronchial hyperresponsiveness. The hyperresponsive group had more experience of bronchitis and asthma in the past than the non-responsive group. The lower $FEV_1\;and\;FEV_1%$ were closely related with bronchial hyperresponsiveness. Bronchial hyperresponsiveness seems to be associated with some of respiratory symptoms, past histories and pulmonary function parameters in workers exposed to isocyanates.

한 콘돔공장근로자들의 수근관증후군에 관한 연구

강중구,백도명,이윤정,마효일,손미아,이홍기,최정근,Kang, Joong-Koo,Paek, Do-Myung,Lee, Young-Jung,Ma, Hyeo-Il,Son, Mi-A,Lee, Hong-Ki,Choi, Jung-Keun 대한예방의학회 1996 Journal of Preventive Medicine and Public Health Vol.29 No.3

The objectives of this study are to investigate the prevalence of occupation related carpal tunnel syndrome(CTS) among workers in a condom industry : to analyse the sensitivity and specificity of clinical signs or symptoms such as hand diagram, Tinel's sign and Phalen's sign in carpal tunnel syndrome : and to test vibration threshold test using audiometry as a technically easy and noninvasive method in the diagnosis of carpal tunnel syndrome in stead of nerve conduction velocity (NCV). The study group was divided into exposed group(39 cases) and non-exposed group(48 cases) based on whether or not excessive use of wrist movements exsist. 1. There are stastically significant differences in symptoms and signs of carpal tunnel syndrome such as hand diagram, Tinel's sign and Phalen's sign between exposed and non-exposed group(p<0.05). 2. Six cases(9 hands) were comfirmed as carpal tunnel syndrome by NCV. Five cases(7 hands) belonged to exposed group, 1 case(2 hands) to nonexposed group. As there are significant differences in prevalence of carpal tunnel syndrome between two groups(p<0.05), excessive use of wrist in occupation is a risk factor of carpal tunnel syndrome. 3. When we use NCV as a gold standard in the diagnosis of carpal tunnel syndrome, sensitivity and specificity of hand diagram, Tinel's sign and Phalen's sign is as followed; hand diagram , sensitivity 88.9%, specificity 84.2% Tinel's sign ; sensitivity 55.6%, specificity 72.8% Phalen's sign ; sensitivity 14.3%, specificity 88.4%. Among above clinical signs and symptoms, hand diagram is the best clinical screening test. 4. The differences of vibration threshold between median and ulnar nerve at the same time are useful in the diagnosis of carpal tunnel syndrome but the time change of vibration threshold of median nerve over time are not sensitive enough. It is concluded that vibration threshold between median and ulnar nerve at the same time can be used as a supplementary or alternative criterion to indicate that the nerve dysfunction is located in the carpal tunnel.

수술적 치료가 필요한 요추 척추관 협착증에서 선택적 척추 신경근 차단술의 치료 효과

이기행(Kee-Heang Lee),정창훈(Chang-Whoon Chung),문찬웅(Chan-Woong Moon),유종민(Jong-Min Yoo),최정근(Jung-Keun Choi),김윤수(Youn Soo Kim) 대한정형외과학회 2005 대한정형외과학회지 Vol.40 No.3

목적: 수술적 치료가 적응이 되는 요추 척추관 협착증 환자에서 선택적 척추 신경근 차단술의 효과를 판정하기 위하여 이 연구를 하였다. 대상 및 방법: 1998년 4월부터 2002년 10월 사이에 전산화 단충 촬영을 이용한 선택적 척추 신경근 차단술을 시행했던 환자 중 수술의 적응증이 되었으나 마취 및 수술의 위험성이 높아 수술을 하지 못한 21명의 요추 척추관 협착증 환자를 대상으로 평균 19.5개월간(최소 12개월, 최장 60개월) 추시하였다. 남자 9명, 여자 12명이었으며 평균 연령은 66.4세(58-78세)였다. 의무 기록, 방사선학적 검사 소견을 조사하였고 필요시에 전화 면담을 시행하였다. 마취 및 수술의 위험성은 American Society of Anesthesiologist (ASA) physical status classification을 기준으로 평가하였다. 선택적 척추 신경근 차단술 후 9개월과 최종 추시 시의 Kirkaldy-Willis의 기준에 의거한 결과와, 선택적 척추 신경근 차단술 후 2주, 1개월, 3개월, 5개월, 9개월 그리고 최종 추시 시에 증상의 재발을 결과 판정에 이용하였다. 결과: 총 21예 중 ASA 기준으로 3급이 8예, 4급이 13예였다. 수술을 하지 못한 주된 원인은 심장 질환이 17예(81%), 신장 질환이 2예(9.5%), 내분비 질환이 2예(9.5%)였다. 증상의 발현부터 선택적 척추 신경근 차단술 사이의 기간은 1개월에서 30년(평균 41.6개월)이었다. 3예를 제외한 18예에서 평균 1.9개월(최소 1일, 최장 9개월)에 차단술 시행 전과 같은 정도의 동통이 재발하였다. Kirkaldy-Willis의 기준에 의한 결과는 9개월에는 우수는 없었고, 양호 1예(4.8%), 보통 2예(9.5%), 불량 18예(85.7%)였다. 최종 추시 시에 4예를 제외한 전 예에서 결과가 변화는 없었으나, 4예에서는 특별한 치료 없이 호전 되었다(불량에서 양호 2예, 불량에서 보통 2예). 결론: 선택적 척추 신경근 차단술 후 요추 척추관 협착증의 증상의 호전은 단기간(평균 1.9개월)이었다. 이 같은 결과로 보아 선택적 척추 신경근 차단술은 수술의 적응이 되는 척추관 협착증 환자에서는 추천이 되지 않는다. Purpose: This study evaluated the effectiveness of a selective nerve root block (SNRB) for a lumbar spinal stenosis (LSS) that indicated surgery. Materials and Methods: Twenty-one LSS patients, who were indicated for surgery but could not be operated on due to a high anesthetic risk, were evaluated retrospectively an evaluated on average of 19.5 months (range, 12 to 60 months) following the SNRB from April 1998 to October 2002. There were 9 males and 12 females with a mean age of 66.4 years (range, 59 to 78 years). The medical records and radiologic studies were reviewed, and a telephone interview was carried out where needed. The anesthetic risk was evaluated by the American Society of Anesthesiologists (ASA) physical status classification. The Kirkaldy-Willis criteria (at 9 months after SNRB and last FU) and the recurrence of symptoms (at 2 weeks, 1 month, 3 months, 5 months, 9 months after the SNRB, and the last FU) were analyzed. Results: Among the 21 patients, 8 patients were in the ASA class 3, 13 in class 4. The major physical conditions that indicated a high anesthetic risk was cardiac problems in 17 patients, renal problems in 2, and endocrine problem in 2. The interval between the onset of symptom and the SNRB ranged from one month to 30 years (average, 41.6 months). All but 3 patients had a recurrence of their symptoms at an average 1.9 months (range, 1 day to 9 months) after the SNRB. According to the Kirkardy-Wills criteria, 9 months after SNRB, the results were good in 1 patient, fair in 2, and poor in 18. At the last follow-up, all but 4 patients did not show a chang in their status according to the Kirkardy-Wills criteria, and 4 patients improved (poor to good in 2, poor to fair in 2) without treatment. Conclusion: The symptoms of LSS improved for a very short period (average, 1.9 month) by SNRB. These results suggest that SNRB suitable for the LSS patients who require need surgery.