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Zuo Z, Zeng W, Peng K, Mao Y, Wu Y, Zhou Y, Qi W. Development of a novel combined nomogram integrating deep-learning-assisted CT texture and clinical-radiological features to predict the invasiveness of clinical stage IA part-solid lung adenocarcinoma: a multicentre study. Clin Radiol 2023; 78:e698-e706. [PMID: 37487842 DOI: 10.1016/j.crad.2023.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 11/30/2022] [Accepted: 07/01/2023] [Indexed: 07/26/2023]
Abstract
AIM To develop a novel combined nomogram based on deep-learning-assisted computed tomography (CT) texture (DL-TA) and clinical-radiological features for the preoperative prediction of invasiveness in patients with clinical stage IA lung adenocarcinoma manifesting as part-solid nodules (PSNs). MATERIALS AND METHODS This study was conducted from January 2015 to October 2021 at three centres: 355 patients with 355 PSN lung adenocarcinomas who underwent surgical resection were included and classified into the training (n=222) and validation (n=133) cohorts. PSN segmentation on CT images was performed automatically with a commercial deep-learning algorithm, and CT texture features were extracted. The least absolute shrinkage and selection operator was used for feature selection and transformed into a DL-TA score. The combined nomogram that incorporated the DL-TA score and identified clinical-radiological features was developed for the prediction of pathological invasiveness of the PSNs and validated in terms of discrimination and calibration. RESULTS The present study generated a combined nomogram for predicting the invasiveness of PSNs that included age, consolidation-to-tumour ratio, smoking status, and DL-TA score, with a C-index of 0.851 (95% confidence interval: 0.826-0.877) for the training cohort and 0.854 (95% confidence interval: 0.817-0.891) for the validation cohort, indicating good discrimination. Furthermore, the model had a Brier score of 0.153 for the training cohort and 0.135 for the validation cohort, indicating good calibration. CONCLUSION The developed combined nomogram consisting of the DL-TA score and clinical-radiological features and has the potential to predict the individual risk for the invasiveness of stage IA PSN lung adenocarcinomas.
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Affiliation(s)
- Z Zuo
- Department of Radiology, Xiangtan Central Hospital, Xiangtan, Hunan 411000, China
| | - W Zeng
- Department of Radiology, Xiangtan Central Hospital, Xiangtan, Hunan 411000, China
| | - K Peng
- Department of Spine Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China
| | - Y Mao
- Department of Radiology, The Affiliated Changsha Central Hospital, Hengyang Medical School, University of South China, Changsha, Hunan 410004, China
| | - Y Wu
- Department of Radiology, Xiangtan Central Hospital, Xiangtan, Hunan 411000, China
| | - Y Zhou
- Department of Radiology, Xiangtan Central Hospital, Xiangtan, Hunan 411000, China
| | - W Qi
- Department of Radiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan 646100, China.
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He N, Xi Y, Yu D, Yu C, Shen W. Construction of IL-1 signalling pathway correlation model in lung adenocarcinoma and association with immune microenvironment prognosis and immunotherapy: Multi-data validation. Front Immunol 2023; 14:1116789. [PMID: 36865560 PMCID: PMC9972222 DOI: 10.3389/fimmu.2023.1116789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 02/01/2023] [Indexed: 02/12/2023] Open
Abstract
Numerous studies have confirmed the inextricable link between inflammation and malignancy, which is also involved in developing lung adenocarcinoma, where IL-1 signalling is crucial. However, the predictive role of single gene biomarkers is insufficient, and more accurate prognostic models are needed. We downloaded data related to lung adenocarcinoma patients from the GDC, GEO, TISCH2 and TCGA databases for data analysis, model construction and differential gene expression analysis. The genes of IL-1 signalling-related factors were screened from published papers for subgroup typing and predictive correlation analysis. Five prognostic genes associated with IL-1 signalling were finally identified to construct prognostic prediction models. The K-M curves indicated that the prognostic models had significant predictive efficacy. Further immune infiltration scores showed that IL-1 signalling was mainly associated with enhanced immune cells, drug sensitivity of model genes was analysed using the GDSC database, and correlation of critical memories with cell subpopulation components was observed using single-cell analysis. In conclusion, we propose a predictive model based on IL-1 signalling-related factors, a non-invasive predictive approach for genomic characterisation, in predicting patients' survival outcomes. The therapeutic response has shown satisfactory and effective performance. More interdisciplinary areas combining medicine and electronics will be explored in the future.
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Affiliation(s)
- Ningning He
- Department of Thoracic Surgery, Ningbo Medical Center Lihuili Hospital, Ningbo University, Ningbo, Zhejiang, China
| | - Yong Xi
- Department of Thoracic Surgery, Ningbo Medical Center Lihuili Hospital, Ningbo University, Ningbo, Zhejiang, China,*Correspondence: Yong Xi,
| | - Dongyue Yu
- College of Life Sciences, Nankai University, Tianjin, China
| | - Chaoqun Yu
- Department of Thoracic Surgery, Ningbo Medical Center Lihuili Hospital, Ningbo University, Ningbo, Zhejiang, China
| | - Weiyu Shen
- Department of Thoracic Surgery, Ningbo Medical Center Lihuili Hospital, Ningbo University, Ningbo, Zhejiang, China
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Qiu ZB, Zhang C, Chu XP, Cai FY, Yang XN, Wu YL, Zhong WZ. Quantifying invasiveness of clinical stage IA lung adenocarcinoma with computed tomography texture features. J Thorac Cardiovasc Surg 2022; 163:805-815.e3. [PMID: 33541730 DOI: 10.1016/j.jtcvs.2020.12.092] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 11/21/2020] [Accepted: 12/11/2020] [Indexed: 02/05/2023]
Abstract
OBJECTIVES The study objectives were to establish and validate a nomogram for pathological invasiveness prediction in clinical stage IA lung adenocarcinoma and to help identify those potentially unsuitable for sublobar resection-based computed tomography texture features. METHOD Patients with clinical stage IA lung adenocarcinoma who underwent surgery at Guangdong Provincial People's Hospital between January 2015 and October 2018 were retrospectively reviewed. All surgically resected nodules were pathologically classified into less-invasive and invasive cohorts. Each nodule was manually segmented, and its computerized texture features were extracted. Clinicopathological and computed tomographic texture features were compared between 2 cohorts. A nomogram for distinguishing the pathological invasiveness was established and validated. RESULTS Among 428 enrolled patients, 249 were diagnosed with invasive pathological subtypes. Smoking status (odds ratio, 2.906; 95% confidence interval, 1.285-6.579; P = .011), mean computed tomography attenuation value (odds ratio, 1.005, 95% confidence interval, 1.002-1.007; P < .001), and entropy (odds ratio, 8.536, 95% confidence interval, 3.478-20.951; P < .001) were identified as independent predictors for pathological invasiveness by multivariate logistics regression analysis. The nomogram showed good calibration (P = .182) with an area under the curve of 0.849 when validated with testing set data. Decision curve analysis indicated the potentially clinical usefulness of the model with respect to treat-all or treat-none scenario. Compared with intraoperative frozen-section, the nomogram performed better in pathological invasiveness diagnosis (area under the curve, 0.815 vs 0.670; P = .00095). CONCLUSIONS We established and validated a nomogram to compute the probability of invasiveness of clinical stage IA lung adenocarcinoma with great calibration, which may contribute to decisions related to resection extent.
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Affiliation(s)
- Zhen-Bin Qiu
- Guangdong Lung Cancer Institute, Guangdong Provincial Key Laboratory of Translational Medicine in Lung Cancer, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China; Shantou University Medical College, Shantou, China
| | - Chao Zhang
- Guangdong Lung Cancer Institute, Guangdong Provincial Key Laboratory of Translational Medicine in Lung Cancer, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China; School of Medicine, South China University of Technology, Guangzhou, China
| | - Xiang-Peng Chu
- Guangdong Lung Cancer Institute, Guangdong Provincial Key Laboratory of Translational Medicine in Lung Cancer, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China; School of Medicine, South China University of Technology, Guangzhou, China
| | - Fei-Yue Cai
- Perception Vision Medical Technologies Co Ltd, Guangzhou, China
| | - Xue-Ning Yang
- Guangdong Lung Cancer Institute, Guangdong Provincial Key Laboratory of Translational Medicine in Lung Cancer, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Yi-Long Wu
- Guangdong Lung Cancer Institute, Guangdong Provincial Key Laboratory of Translational Medicine in Lung Cancer, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Wen-Zhao Zhong
- Guangdong Lung Cancer Institute, Guangdong Provincial Key Laboratory of Translational Medicine in Lung Cancer, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.
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Sung MR, Tomasini P, Le LW, Kamel-Reid S, Tsao MS, Liu G, Bradbury PA, Shepherd FA, Li JJ, Feld R, Leighl NB. Effects of Ethnicity on Outcomes of Patients With EGFR Mutation–Positive NSCLC Treated With EGFR Tyrosine Kinase Inhibitors and Surgical Resection. JTO Clin Res Rep 2022; 3:100259. [PMID: 35112092 PMCID: PMC8790496 DOI: 10.1016/j.jtocrr.2021.100259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 11/15/2021] [Accepted: 11/18/2021] [Indexed: 12/09/2022] Open
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Xiao F, Yu Q, Zhang Z, Liu D, Guo Y, Liang C, Wang B, Sun H. Novel perspective to evaluate the safety of segmentectomy: clinical significance of lobar and segmental lymph node metastasis in cT1N0M0 lung adenocarcinoma. Eur J Cardiothorac Surg 2018; 53:228-234. [PMID: 28950357 DOI: 10.1093/ejcts/ezx263] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Accepted: 06/27/2017] [Indexed: 02/02/2023] Open
Abstract
OBJECTIVES The regularity of intrapulmonary lobar and segmental lymph node (LSN) metastasis in cT1N0M0 stage lung adenocarcinoma remains unclear. Thus, segmentectomy with uncertain LSN metastatic status remains a potential oncological risk. We aimed to facilitate more accurate determination of N staging and filter more suitable cases for segmentectomy. METHODS A prospective study was performed from March 2014 to September 2016. A total of 196 patients diagnosed with cT1N0M0 stage lung adenocarcinoma were enrolled and received lobectomy together with mediastinal lymph node dissection. The intrapulmonary LSNs were dissected and classified as adjacent LSN or isolated LSN. The metastatic status of the LSNs together with the TNM staging were analysed. A comparison of the metastatic probability of isolated LSN was carried out considering the metastatic status of adjacent LSN, imaging features, smoking history, pathological subtypes, size of the lesions and serum level of tumour markers (carcinoembryonic antigen and Cyfra21-1). RESULTS Among the 196 cases enrolled, 152 were confirmed as pN0, 36 as pN1, 6 as pN1 + N2 and 2 as skip pN2. When the LSNs had not been dissected, the false-negative rate for N staging was 9.0% (15 of 167). Patients with adjacent LSN metastasis (P < 0.001), solid nodule (P = 0.001), non-lepidic predominant invasive adenocarcinoma (P < 0.001), nodules with maximum diameter larger than 2 cm (P < 0.001) and those with elevated serum carcinoembryonic antigen level (>5 ng/ml) (P = 0.005) had a higher isolated LSN metastasis rate. No significant difference in isolated LSN metastasis rate was found between groups with or without smoking history (P = 0.90) and with different serum Cyfra21-1 levels (P = 0.14). CONCLUSIONS Dissection of intrapulmonary LSNs reduces the false-negative rate of lymph node metastasis. Solid nodule, non-lepidic predominant invasive adenocarcinoma, lung adenocarcinoma larger than 2 cm in maximum diameter or with elevated serum carcinoembryonic antigen level (>5 ng/ml) might not be suitable for segmentectomy. The lymph node sampling area during segmentectomy should include adjacent LSNs of the target segment. When metastasis to the adjacent LSNs is confirmed by fast-frozen pathology, segmentectomy would not be suitable.
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Affiliation(s)
- Fei Xiao
- Department of Thoracic Surgery, National Clinical Research Center for Respiratory Diseases, Center for Respiratory Diseases, China-Japan Friendship Hospital, Chaoyang District, Beijing, China
| | - Qiduo Yu
- Department of Thoracic Surgery, National Clinical Research Center for Respiratory Diseases, Center for Respiratory Diseases, China-Japan Friendship Hospital, Chaoyang District, Beijing, China
| | - Zhenrong Zhang
- Department of Thoracic Surgery, National Clinical Research Center for Respiratory Diseases, Center for Respiratory Diseases, China-Japan Friendship Hospital, Chaoyang District, Beijing, China
| | - Deruo Liu
- Department of Thoracic Surgery, National Clinical Research Center for Respiratory Diseases, Center for Respiratory Diseases, China-Japan Friendship Hospital, Chaoyang District, Beijing, China
| | - Yongqing Guo
- Department of Thoracic Surgery, National Clinical Research Center for Respiratory Diseases, Center for Respiratory Diseases, China-Japan Friendship Hospital, Chaoyang District, Beijing, China
| | - Chaoyang Liang
- Department of Thoracic Surgery, National Clinical Research Center for Respiratory Diseases, Center for Respiratory Diseases, China-Japan Friendship Hospital, Chaoyang District, Beijing, China
| | - Bei Wang
- Department of Pathology, China-Japan Friendship Hospital, Chaoyang District, Beijing, China
| | - Hongliang Sun
- Department of Radiology, China-Japan Friendship Hospital, Chaoyang District, Beijing, China
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Horiuchi Y, Fujisaki J, Ishizuka N, Omae M, Ishiyama A, Yoshio T, Hirasawa T, Yamamoto Y, Nagahama M, Takahashi H, Tsuchida T. Study on Clinical Factors Involved in Helicobacter pylori-Uninfected, Undifferentiated-Type Early Gastric Cancer. Digestion 2017; 96:213-219. [PMID: 29050004 DOI: 10.1159/000481817] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 09/27/2017] [Indexed: 02/04/2023]
Abstract
BACKGROUND The factors associated with the pathogenesis of Helicobacter pylori-uninfected undifferentiated-type early gastric cancer (HPUGC) remain unclear. This study compared patient characteristics, including medical history and alcohol/tobacco use, of HPUGC patients with characteristics of patients with H. pylori-positive undifferentiated-type early gastric cancer (HPPGC) to clarify and gain understanding on those differences that could play a role in the pathogenesis. METHODS This retrospective study included 282 patients who were treated endoscopically from March 2005 to March 2014. This cohort consisted of 232 patients with HPPGC (82.3%) and 50 patients with HPUGC (17.7%). Patient characteristics were analyzed by subgroups of HPUGC vs. HPPGC, with comparisons for age, gender, cancer history, comorbidity of lifestyle diseases requiring medication (hypertension, type 2 diabetes, and dyslipidemia), cumulative amount of alcohol consumption, and smoking history (Brinkman index [BI]). RESULTS HPUGC patients were typically younger, had less frequent hypertension, and had higher BI values (p < 0.05 for all parameters). In a younger non-hypertensive subgroup, the OR for high BI (BI ≥340) in the HPUGC group vs. HPPGC group was 5.049 (95% CI 2.458-10.373, p < 0.0001). CONCLUSIONS The investigation of clinical factors identified smoking history as being possibly contributing to the pathogenesis of HPUGC. Future research is necessary at the cellular and genetic levels.
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Affiliation(s)
- Yusuke Horiuchi
- Department of Gastroenterology, Cancer Institute Hospital, Tokyo, Japan
| | - Junko Fujisaki
- Department of Gastroenterology, Cancer Institute Hospital, Tokyo, Japan
| | - Naoki Ishizuka
- Department of Clinical Trial Planning and Management, Cancer Institute Hospital, Tokyo, Japan
| | - Masami Omae
- Department of Gastroenterology, Cancer Institute Hospital, Tokyo, Japan
| | - Akiyoshi Ishiyama
- Department of Gastroenterology, Cancer Institute Hospital, Tokyo, Japan
| | - Toshiyuki Yoshio
- Department of Gastroenterology, Cancer Institute Hospital, Tokyo, Japan
| | - Toshiaki Hirasawa
- Department of Gastroenterology, Cancer Institute Hospital, Tokyo, Japan
| | - Yorimasa Yamamoto
- Department of Gastroenterology, Showa University Fujigaoka Hospital, Yokohama, Japan
| | - Masatsugu Nagahama
- Department of Gastroenterology, Showa University Fujigaoka Hospital, Yokohama, Japan
| | - Hiroshi Takahashi
- Department of Gastroenterology, Showa University Fujigaoka Hospital, Yokohama, Japan
| | - Tomohiro Tsuchida
- Department of Gastroenterology, Cancer Institute Hospital, Tokyo, Japan
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Miao Y, Zhang J, Zou J, Zhu Q, Lv T, Song Y. Correlation in histological subtypes with high resolution computed tomography signatures of early stage lung adenocarcinoma. Transl Lung Cancer Res 2017; 6:14-22. [PMID: 28331820 DOI: 10.21037/tlcr.2017.02.06] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Uncertainty remains on the association between image characteristics of the nodules in computed tomography (CT) scans and lung adenocarcinoma histopathologic subtypes. We aimed to estimate the correlation between preoperative high resolution computed tomography (HRCT) scan and postoperative histopathology of stage IA lung adenocarcinoma in East Asian Chinese population. METHODS We retrospectively reviewed the clinical records and HRCT images of 190 patients (106 female and 84 male) with resected, preoperatively untreated stage IA adenocarcinomas. The relationship between image characteristics of nodules at preoperative HRCT and their histological subtypes after resection were analyzed. The one-way ANOVA, chi-square test and logistic regression were used for analysis. RESULTS In 190 patients with stage IA lung adenocarcinoma, median tumor diameter was significantly lower in lepidic predominant invasive adenocarcinoma (LPA) (15.96±6.95 mm). Univariate analysis revealed that ground-glass opacity (GGO) proportion (P<0.001), margin (P<0.001), border definition (P=0.015), pleural retraction (P<0.001) and enhancement (P<0.001) had statistically significant differences in four histological subtypes. The multivariate analysis referenced for lepidic group which indicated that GGO proportion and pleural retraction were independent associated with acinar group (RR=4.221, 95% CI: 1.770-10.066, P=0.001; RR=0.380, 95% CI: 0.158-0.916, P=0.031, respectively). Male and whose nodule margin with spiculation or lobulation were prone to papillary predominant invasive adenocarcinoma (PPA) (RR=0.288, 95% CI: 0.090-0.920, P=0.036; RR=0.250, 95% CI: 0.070-0.887, P=0.032, respectively). GGO proportion and nodule margin were independent related factors in solid predominant invasive adenocarcinoma (SPA) (RR=13.338, 95% CI: 2.974-59.811, P=0.001; RR=0.097, 95% CI: 0.016-0.606, P=0.013, respectively). CONCLUSIONS Nodules with spiculation or lobulation and less GGO proportion are determinants of histological subtypes with poor prognosis in stage IA lung adenocarcinoma patients according to the 2011 histologic IASLC/ATS/ERS classification.
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Affiliation(s)
- Yingying Miao
- Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medical, Nanjing 210002, China;; Nanjing University Institute of Respiratory Medicine, Nanjing 210002, China
| | - Jianya Zhang
- Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medical, Nanjing 210002, China;; Nanjing University Institute of Respiratory Medicine, Nanjing 210002, China
| | - Jiawei Zou
- Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medical, Nanjing 210002, China;; Nanjing University Institute of Respiratory Medicine, Nanjing 210002, China
| | - Qingqing Zhu
- Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medical, Nanjing 210002, China;; Nanjing University Institute of Respiratory Medicine, Nanjing 210002, China
| | - Tangfeng Lv
- Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medical, Nanjing 210002, China;; Nanjing University Institute of Respiratory Medicine, Nanjing 210002, China
| | - Yong Song
- Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medical, Nanjing 210002, China;; Nanjing University Institute of Respiratory Medicine, Nanjing 210002, China
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Bar-Ad V, Palmer J, Li L, Lai Y, Lu B, Myers RE, Ye Z, Axelrod R, Johnson JM, Werner-Wasik M, Cowan SW, Evans NR, Hehn BT, Solomides CC, Wang C. Neutrophil to lymphocyte ratio associated with prognosis of lung cancer. Clin Transl Oncol 2016; 19:711-717. [DOI: 10.1007/s12094-016-1593-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 11/23/2016] [Indexed: 01/04/2023]
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Watanabe S, Nojima I, Agarie Y, Watanabe T, Fukuhara S, Fujinaga T, Oka H. Electrically induced mechanomyograms reflect inspiratory muscle strength in young or elderly subjects. Respir Investig 2016; 54:436-444. [PMID: 27886855 DOI: 10.1016/j.resinv.2016.06.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 06/02/2016] [Accepted: 06/03/2016] [Indexed: 06/06/2023]
Abstract
BACKGROUND Respiratory muscle strength has been used as a tool for evaluating respiratory rehabilitation in chronic obstructive pulmonary disease. However, mouth pressure measurement evaluated by maximum expiratory mouth pressure (PEmax) or inspiratory mouth pressure (PImax) offers an indirect method for measuring respiratory muscle strength. We demonstrated the evaluation of diaphragm contractility using a mechanomyogram (MMG), which is the mechanical signal generated by the motion of the diaphragm induced by the electric stimulation of the phrenic nerve. METHODS Study participants were 21 young and 20 elderly subjects with no symptoms of respiratory disease. The elderly subjects were divided into non-smoker or smoker groups. The smoker group was defined as subjects having a Brinkman Index of greater than 300. We measured basic spirometric parameters, mouth pressure (PEmax, PImax), and diaphragmatic MMG. RESULTS Diaphragmatic MMG showed more clear contrast between young subjects and elderly non-smoker or smoker subjects than the conventional method for respiratory muscle contraction (PEmax, PImax). In addition, the diaphragmatic MMG strongly correlated with inspiratory muscle strength. CONCLUSIONS Diaphragmatic MMG may reflect diaphragmatic contractility more directly and sensitively than the conventional method.
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Affiliation(s)
- Shogo Watanabe
- Department of Medical Technology, Graduate School of Health Sciences, Okayama University, 2-5-1, Shikata-cho, Kita-ku, Okayama 700-8558, Japan.
| | - Ippei Nojima
- Department of Physical and Occupational Therapy, Nagoya University Graduate School of Medicine, 1-1-20, Daiko-Minami, Higashi-ku, Nagoya, Aichi, Japan.
| | - Yuuna Agarie
- Department of Rehabilitation Science, Nagoya University School of Health Sciences, 1-1-20, Daiko-Minami, Higashi-ku, Nagoya, Aichi, Japan.
| | - Tatsunori Watanabe
- Department of Physical and Occupational Therapy, Nagoya University Graduate School of Medicine, 1-1-20, Daiko-Minami, Higashi-ku, Nagoya, Aichi, Japan.
| | - Shinichi Fukuhara
- Department of Medical Technology, Graduate School of Health Sciences, Okayama University, 2-5-1, Shikata-cho, Kita-ku, Okayama 700-8558, Japan; Department of Medical Engineering, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare, 288, Matsushima, Kurashiki, Okayama, Japan.
| | - Takeshi Fujinaga
- Department of Medical Technology, Graduate School of Health Sciences, Okayama University, 2-5-1, Shikata-cho, Kita-ku, Okayama 700-8558, Japan.
| | - Hisao Oka
- Department of Medical Technology, Graduate School of Health Sciences, Okayama University, 2-5-1, Shikata-cho, Kita-ku, Okayama 700-8558, Japan.
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