Spirometric Pulmonary Function Tests Research Articles

Maximal Inspiratory and Expiratory Pressures in Men with Chronic Obstructive Pulmonary Disease: A Cross-Sectional Study

Introduction: Respiratory muscle dysfunction is a cardinal feature in chronic obstructive pulmonary disease (COPD) contributing to decreased exercise capacity and pulmonary function test (PFT) limitation with progression of the disease. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) are reliable parameters for assessing the respiratory muscle strength. Aims: This study aims to measure maximal inspiratory and expiratory pressures in male COPD patients, to determine their correlates, and to study the relationship between the severity of COPD and respiratory muscle strength. Patients and Methods: This was an observational, cross-sectional study. A total of 100 males, who were known COPD patients and who were clinically stable, were recruited. Both inpatients and outpatients were studied. Spirometric PFT test was done, and MIP and MEP were measured using respiratory pressure meter. Descriptive statistics and Pearson's correlation were used. Results: The mean (± standard deviation) MIP and MEP were 47.73 (±19.6) cm H2O and 60.76 (±11.6) cm H2O, respectively. MIP and MEP showed a highly significant correlation (P

Effects of Sildenafil on spirometric pulmonary function parameters, pulmonary artery systolic pressure and BNP levels in patients with chronic obstructive pulmonary disease and erectile dysfunction

We aimed to investigate the effects of Sildenafil on pulmonary artery systolic pressure (PASP) as well as forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) and serum brain-type natriuretic peptide (BNP) levels in stable chronic obstructive pulmonary disease (COPD) patients with erectile dysfunction (ED). This was a prospective non-controlled interventional study that recruited COPD patients with ED between the ages of 49 and 79. International Index of Erectile Dysfunction Form (IIEF-5) was used for the evaluation of ED. Patients who had pulmonary artery systolic pressure >50 mmHg were included in the study. Single-dose Sildenafil 100 mg was administered orally to the patients. Before and after the drug ingestion, spirometry and echocardiographic measurements were performed, and serum BNP levels were measured as well. Forty-five male COPD patients with ED were included. Both percent predicted, and absolute FEV1 values increased significantly after the Sildenafil administration compared with baseline values (p<0.01). Similarly, the FEV1/FVC ratio also increased significantly with the Sildenafil administration compared to baseline values (p<0.01). Pulmonary artery systolic pressure significantly decreased from its baseline value with Sildenafil administration (p<0.01). Serum BNP values significantly reduced with Sildenafil administration compared to the pre-treatment values (p<0.01). This is the first study conducted in COPD patients with erectile dysfunction who had also pulmonary hypertension. The single-dose Sildenafil administration reduced PASP and serum BNP levels significantly. For the first time in the literature, we showed that the spirometric pulmonary function tests, namely FEV1 and FEV1/FVC ratio, improved significantly with the Sildenafil administration.

Relationship between rosacea and chronic obstructive pulmonary disease: Rosacea and comorbidities: Rosacea and comorbidities.

Rosacea is a chronic inflammatory skin disease that has been reported to be associated with many systemic disorders including respiratory diseases. This study aims to investigate respiratory function in patients with rosacea. Patients with rosacea and age- and gender-matched healthy volunteers were included in this cross-sectional study. Spirometric pulmonary function tests including the percentage of forced vital capacity (FVC%), percentage of forced expiratory volume in one second (FEV 1%), forced expiratory flow at 25-75% of FVC (FEF 25-75%), and FEV 1/FVC ratio was assessed in both patient and controls. The potential relationship between rosacea severity and pulmonary functions was assessed. A total of 120 patients with rosacea and 120healthy controls were enrolled in the study. Compared to the controls, FEV 1%, FEV 1/FVC%, and FEF 25-75% values were significantly lower in patients with rosacea. Lower FEV 1/FVC% values were found to be associated with disease severity. FEV 1%, FEV 1/FVC%, and FEF 25-75% values were found to be more useful in differentiating the patients from healthy subjects. This study showed that patients with rosacea may have abnormal respiratory function compared to healthy subjects. Besides, disease severity was associated with worse respiratory functions. We believe that patients with rosacea, particularly those with additional risk factors, should be screened for respiratory disorders.

Investigation of the evolution of radiation-induced lung damage using serial CT imaging and pulmonary function tests

Background and purposeRadiation-induced lung damage (RILD) is a common consequence of lung cancer radiotherapy (RT) with unclear evolution over time. We quantify radiological RILD longitudinally and correlate it with dosimetry and respiratory morbidity. Materials and methodsCTs were available pre-RT and at 3, 6, 12 and 24-months post-RT for forty-five subjects enrolled in a phase 1/2 clinical trial of isotoxic, dose-escalated chemoradiotherapy for locally advanced non-small cell lung cancer. Fifteen CT-based measures of parenchymal, pleural and lung volume change, and anatomical distortions, were calculated. Respiratory morbidity was assessed with the Medical Research Council (MRC) dyspnoea score and spirometric pulmonary function tests (PFTs): FVC, FEV1, FEV1/FVC and DLCO. ResultsFEV1, FEV1/FVC and MRC scores progressively declined post-RT; FVC decreased by 6-months before partially recovering. Radiologically, an early phase (3–6 months) of acute inflammation was characterised by reversible parenchymal change and non-progressive anatomical distortion. A phase of chronic scarring followed (6–24 months) with irreversible parenchymal change, progressive volume loss and anatomical distortion. Post-RT increase in contralateral lung volume was common. Normal lung volume shrinkage correlated longitudinally with mean lung dose (r = 0.30–0.40, p = 0.01–0.04). Radiological findings allowed separation of patients with predominant acute versus chronic RILD; subjects with predominantly chronic RILD had poorer pre-RT lung function. ConclusionsCT-based measures enable detailed quantification of the longitudinal evolution of RILD. The majority of patients developed progressive lung damage, even when the early phase was absent or mild. Pre-RT lung function and RT dosimetry may allow to identify subjects at increased risk of RILD.

Pulmonary dysfunction: A predictor of postoperative outcome in severe mitral stenosis

Background: Pulmonary function (PF) derangements in mitral stenosis (MS) can have an impact on the postmitral valve-replacement (MVR) period, which is not well studied. Objectives: The objectives were (1) to study the impact of the preoperative PF derangements intrinsic to MS on the early postoperative outcome and (2) to assess the prognostic relevance of spirometric tests as to the postoperative complications and morbidity. Methods: Prospective observational study: The spirometric pulmonary function tests (PFTs) performed in 25 patients with isolated MS (nonrandomized sampling) and arterial blood gas (ABG) were correlated to postoperative (post-MVR) variables: duration of ventilation, intensive care unit (ICU) stay, hospital stay, ABG, pulmonary complications, and outcome. Data were analyzed and compared under types, grades, and risk-based groups using nonparametric (Spearman's correlation, Kruskal–Wallis, and Mann–Whitney) tests. Results: The significant correlations were forced vital capacity (FVC)%, forced expiratory volume in 1 s (FEV1), FEV1%, peak expiratory flow rate (PEFR), and oxygen status to ventilation duration (P < 0.05); FEV1, PEFR, forced expiratory flow (FEF)-50, and oxygenation with ICU duration (P < 0.05); FVC, PEFR, and FEF-50 with hospital stay (P < 0.05); FVC, FEV1, and oxygenation to postoperative oxygen status (P = 0.02); FVC and FEV1 to pulmonary complications (P < 0.05); and FVC, PEFR, and FEF-50 with ventilation modification (P < 0.05). The morbidity and respiratory events showed a higher incidence with the mixed and severe categories (though not significant) and also with high-risk group in terms of postoperative pulmonary complications (P = 0.044) and prolonged ventilation. Mild trend toward hypercarbia needed ventilation optimization. Conclusions: PFT derangements in MS play an impact on the postoperative course to varying degrees. The advanced (severe and mixed) derangements and the high-risk group associate with greater morbidity and complications, calling for precautionary care, but on the whole do not contraindicate surgery. Spirometric evaluation can to a certain extent predict the postoperative morbidity risk.

Assessment of Pulmonary Function in Type II Diabetes Patients

Various metabolic and clinical disorders are associated with diabetes mellitus, the most prominent being vascular disease. There may be a relationship between diabetes and reduced lung function, so this study was designed to evaluate the impairment of lung function on spirometry among diabetic patients. The study included 50 type II diabetic patients and 50 healthy persons, confirmed by normal blood glucose levels, as control group. There was a significant reduction in spirometric pulmonary function tests (FEV1 and FVC) of a restrictive pattern in type 2 diabetic patients compared to control subjects. Since the diabetes affects the pulmonary vasculature and the connective tissue, therefore it can cause reduction in the pulmonary function tests. So, it is recommended that simple tests like spirometry may be performed in patients of type II diabetes as early as possible or be used as a preventive measure.

Pulmonary Function Changes Before and After Mitral Valve Surgery in Severe Mitral Stenosis

Abstract Objective This study was undertaken to assess the pulmonary functions in the patients with predominant severe mitral stenosis before corrective mitral valve surgery, then to reassess the same 6 months after surgery and compare them. Patients and Methods Fifty consecutive patients with predominant severe mitral stenosis undergoing mitral valve replacement surgery were included in this prospective observational study. This study was conducted from July 2016 till January 2018 after obtaining approval from the institute's ethics committee and written consent from all the participants. All the patients were evaluated clinically and divided according to New York Heart Association (NYHA) class symptomatology. Computed spirometric pulmonary function tests (PFTs) such as forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), FEV1/FVC ratio, forced expiratory flow (FEF) 25–75%, peak expiratory flow rate (PEFR), and maximum voluntary ventilation (MVV) were performed on each patient 1 day before and 6 months after surgery. Results Fifty study patients were analyzed, mean age was 38.4 ± 10.76 years (15–56 years), and male-to-female ratio was 1:1.38 (21 males and 29 females). NYHA class symptoms improved significantly in most of our patients after surgery (p &lt; 0.01). PFTs such as FVC, FEV1, FEV1/FVC ratio, FEF 25–75%, and MVV showed significant improvement 6 months after surgery (p &lt; 0.01). Though PEFR also improved compared with preoperative values, it was not significant statistically (p &lt; 0.07). Conclusion This study showed that the lung functions are impaired in patients with severe mitral stenosis and improved significantly 6 months after surgery, which does not correlate well with the betterment of NYHA class.

A study of pulmonary function in end-stage renal disease patients on hemodialysis: a cross-sectional study.

The aim here was to study acute effects of hemodialysis among end-stage renal disease (ESRD) patients. Prospective study in tertiary-level care center. Fifty ESRD patients undergoing hemodialysis were studied. Spirometric pulmonary function tests were performed before and after four-hour hemodialysis sessions. The patients' average age was 45.8 ± 10.0 years; 64% were males and 64% had normal body mass index. Anemia (94%) and hypoalbuminemia (72%) were common. Diabetes mellitus (68%), hypertension (34%) and coronary artery disease (18%) were major comorbidities. Forty-five patients (90%) had been on hemodialysis for six months to three years. The patients' pre-dialysis mean forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) were below normal: 45.8 ± 24.9% and 43.5 ± 25.9% of predicted, respectively. After hemodialysis, these increased significantly, to 51.1 ± 23.4% and 49.3 ± 25.5% of predicted, respectively (P < 0.01). The increase in mean FEV1/FVC, from 97.8 ± 20.8% to 99.3 ± 20.1% of predicted, was not significant (P > 0.05). The pre-dialysis mean forced expiratory flow 25-75% was 50.1 ± 31% and increased significantly, to 56.3 ± 31.6% of predicted (P < 0.05). The mean peak expiratory flow was below normal (43.8 ± 30.7%) and increased significantly, to 49.1 ± 29.9% of predicted (P < 0.05). Males and females showed similar directions of change after hemodialysis. Pulmonary function abnormalities are common among ESRD patients. Comparison of pre and post-hemodialysis parameters showed significant improvements, but normal predicted values were still not achieved.

Thoracic complications of upper gastrointestinal endoscopy in Zagazig University Hospitals. A cross-sectional single center study

Upper Gastro Intestinal Endoscopy (UGIE) is a commonly performed diagnostic and/or therapeutic procedure for evaluation of patients with various abdominal complaints. UGIE complications vary including; pneumonia, mediastinitis, oesophago-pleural fistula. The reported complications of UGIE are diverse and vary from one center to another. AimThe study aimed to report the thoracic complications in patients underwent UGIE during the period between July and December 2016. Patients and methodsOne hundred and twenty patients, candidates for UGIE were included in the study. All patients were subjected to: thorough medical history, complete general and local chest and abdominal examination, routine laboratory investigations, chest X-ray and chest computed tomography (CT) if needed, spirometric pulmonary function tests (PFT), arterial blood gases (ABGs), pre and post UGIE. ResultsPatients were 84 males and 36 female, age ranged from 25 to 70years old, hematemesis and/or melena was the most common presentation (65%). Oesophageal varices was the most common endoscopic finding (50% of cases). Chest pain, cough and bronchitis were more common among Oesophageal Varices Sclerotherapy (OVS) patients. Pneumonia, atelectasis, pleural effusion and mediastinitis were reported after OVS. There was significant difference regarding spirometric parameters before, 2days and 3weeks after the procedure in patients underwent OVS and Gastric Varices Sclerotherapy (GVS), while no significant difference was reported in patients underwent Oesophageal Varices (OV) band ligation and peptic ulcer diagnosis before, 2days and 3weeks after the procedure. ConclusionsThoracic complications were more common in OVS and GVS than in OV band ligation.

Cardiopulmonary exercise testing versus spirometry as predictors of cardiopulmonary complications after colorectal surgery

To determine the predictive value of spirometry and cardiopulmonary exercise testing (CPET) preoperatively in patients scheduled to undergo elective colorectal surgery. We compared the preoperative results with the incidence of postoperative cardiopulmonary complications. A total of 103 patients were scheduled to undergo preoperative CPET and spirometry; 14 patients did not attend their appointments and another 20 were unable to perform the test. In all, 69 patients (median age 60 years (range 25–85), 35 males) successfully completed cycle ergometry and lung function tests. Forced expiratory volume in 1 s (FEV1), percent forced expiratory volume in 1 s (FEV1/forced vital capacity (FVC)) and anaerobic threshold (AT) were measured. Patients were divided postoperatively according to whether cardiopulmonary complications were absent (group A) or present (group B). Postoperative cardiopulmonary complications developed in 8 of the 69 patients (12 %). Thirty day mortality was 3 %. AT was significantly higher in group A (mean AT = 13.8; SD ± 3.0; range = 8.1–20.8) than in group B (mean = 10.91; SD ± 3.0; Range = 7.9–12), (p = 0.0006). Spirometric pulmonary function tests (FEV1, p = 0.09) and (FEV1/FVC, p = 0.08) showed no intergroup differences. The median hospital length of stay (HLOS) was significantly higher in the group of patients that suffered cardiopulmonary complications (p = 0.0282). CPET allows the prediction of postoperative cardiopulmonary complications which cannot be anticipated by spirometry. Early detection of high risk patients facilitates the planning of patient specific management strategies which are likely to improve outcome through invasive monitoring and optimisation of cardio-respiratory function.

Relationship Between Functional Exercise Capacity and Lung Functions in Obese Chidren.

Objective:Cardiovascular, respiratory and musculoskeletal system disorders which may affect the functional exercise capacity are common in obese patients. We aimed to investigate the functional exercise capacity and its relationship with functional pulmonary capacity in obese children.Methods:A total of 74 obese and 36 healthy children as a control group were enrolled in the study. Pulmonary functions and functional exercise capacity were measured by spirometry and six-minute walk test (6 MWT), respectively.Results:The distances covered during the 6 MWT in obese and control groups were 570.9±67.5 and 607.8±72.5 meters, respectively (p=0.010). In spirometric pulmonary function tests (PFTs), forced expiratory volume in 1 sec (FEV1) and forced mid-expiratory flows (25-75) were lower in the obese group (p=0.048 and p=0.047, respectively), whereas forced vital capacity (FVC), the FEV1/FVC ratio and peak expiratory flow were not statistically different between the obese and control groups. Multiple regression analysis revealed that among all parameters of anthropometric measures and PFTs, only body mass index standard deviation score (BMI-SDS) was the independent factor influencing 6 MWT.Conclusion:Functional exercise and lung capacities of obese children were diminished as compared to those of non-obese children. The most important factor influencing functional exercise capacity was BMI-SDS.

Correlation of Pulmonary Function Indexes Determined by Low-Dose MDCT With Spirometric Pulmonary Function Tests in Patients With Chronic Obstructive Pulmonary Disease

The objective of our study was to evaluate the correlation between pulmonary function indexes determined by low-dose MDCT and those obtained from routine spirometric pulmonary function tests (PFTs) in patients with chronic obstructive pulmonary disease (COPD). Lung function of patients with COPD stages 0-III was evaluated by both MDCT and spirometric PFTs. Scanning was performed at maximum end-inspiration and maximum end-expiration. A very strong correlation was found between extrapolated expiratory lung volume (LVex) and COPD stage (r = 0.802, p < 0.001) and between extrapolated LVex and the ratio of forced expiratory volume in 1 second and percentage forced vital capacity (FEV1/FVC%) (r = -0.831, p < 0.001). Moreover, strong positive correlations were found between inspiratory lung volume (LVin) and total lung capacity (TLC) (r = 0.658, p < 0.001), LVex and residual volume (RV) (r = 0.683, p < 0.001), extrapolated LVex and RV (r = 0.640, p < 0.001), LVex and RV/TLC (r = 0.602, p < 0.001), LVex/LVin and RV/TLC (r = 0.622, p < 0.001), extrapolated LVex and RV/TLC (r = 0.663, p < 0.001), and LVex and COPD stage (r = 0.697, p < 0.001). Low-dose MDCT lung function indexes correlate well with spirometric PFT results, and the highest correlation is at end-expiration. Low-dose MDCT may be useful for evaluating lung function in patients with COPD.

Analysis of restrictive pulmonary function abnormality using spirometric investigations and QPSO feature selection

Restrictive pulmonary disorders are leading cause of morbidity and mortality worldwide. Spirometric pulmonary function test is the most common method used to assess restrictive disorder. The sub-maximal effort of the patients may often lead to misclassification due to large interdependency among the spirometric parameters. Also, there is requirement that too many parameters are to be analysed by the physician. In this study, Quantum-behaved Particle Swarm Optimisation (QPSO) approach has been used for identification of significant features that are useful in disease diagnosis. Then the selected feature set is evaluated based on the error in prediction of FEV1, PEF and FEV6 using radial basis function neural network. Results show that QPSO is able to identify most significant features in both normal and restrictive. It is also observed that logistic model tree classifier achieves accuracy of 95%. This feature selection appears to aid in detection of pulmonary function disorders using spirometric investigations.

Prognostic factors for bronchoscopic electrocautery and/or argon plasma coagulation in patients with central airway obstruction

BackgroundSignificant portions of central airway stenosis patients present with unresectable disease. Using bronchotherapeutic procedures to maintain a patent airway and improve clinical symptoms and quality of life is a well-known armamentarium technique. AimTo assess the contribution of different physiological and pathological prognostic factors on the yield of endobronchial therapies (argon plasma coagulation (APC) and electrocautery) in patients with central airway obstruction whether derived from malignant or non-malignant etiology. Patients and methodsTwenty nine patients with central airway obstruction, 21 males and eight females, were recruited in the study. All the studied patients were categorized into malignant and non-malignant groups with different pathological varieties. Interventional bronchoscopic procedures were performed under general anesthesia. The flexible bronchoscope was either passed via an endotracheal tube or through the rigid bronchoscope. Collected data included patient demographics, evaluation of performance scale and quality of life status, evaluation of dyspnea, cough and hemoptysis scores before the interventional bronchoscopy and 1 day after the last session. Also the collected data included; length, size, localization and bronchoscopic appearance of the lesion. Duration of symptoms, duration of mechanical ventilation and the presence of collapse prior to the intervention were all recorded. Number of sessions and type of bronchoscopic modalities used were recorded. Spirometric pulmonary function tests were done before and 1day after the last session. ResultsComplete recanalization was achieved in (17/29) 58.6% of patients, while incomplete or partial recanalization was achieved in (12/29) 41.4% of patients. Using linear regression analysis of independent factors affecting patient outcome; it was found that the length of lesion followed by presence of collapse, duration of symptoms and lastly lesion localization whether localized or diffuse (P<0.0005), (P<0.011), (P<0.02) and (P<0.039) were the most independent factors affecting patient outcome. ConclusionFor favorable outcome, selection of patients with central airway obstructing lesions candidates for bronchoscopic argon plasma coagulation and/or electrocautery should rely on several factors including; age, duration of symptoms, performance scale, co-morbidities, pre-therapeutic FEV1%, presence of lung collapse, and length of the obstructing lesion, moreover its shape and localization.

SAT0406 Quantification of interstitial pulmonary fibrosis in systemic sclerosis using an open-source dicom viewer software (OSIRIX)

BackgroundInterstitial pulmonary fibrosis (IPF) is a frequent manifestation in patients with systemic sclerosis (SSc). The severity of lung involvement may vary considerably depending on the underlying disease and it can...

Long-term Changes in Pulmonary Function After Incidental Lung Irradiation for Breast Cancer: A Prospective Study With 7-Year Follow-up

To evaluate late pulmonary function changes after incidental pulmonary irradiation for breast cancer. Forty-three consecutive female patients diagnosed with breast carcinoma and treated with postoperative radiation therapy (RT) at the same dose (50 Gy) and fractionation (2 Gy/fraction, 5 days/week) were enrolled. Pulmonary function tests (PFT) and ventilation/perfusion scans were performed before RT and 6, 12, 24, and 84 months afterward. Forty-one patients, mean age 55 years, were eligible for the analysis. No differences were found in the baseline PFT values for age, smoking status and previous chemotherapy; women undergoing mastectomy showed baseline spirometric PFT values lower than did women treated with conservative surgery. The mean pulmonary dose was 10.9 Gy, being higher in women who also received lymph node RT (15.8 vs 8.6, P<.01). Only 1 patient experienced symptomatic pneumonitis. All PFT values showed a reduction at 6 months. From then on, the forced vital capacity and forced expiratory volume in 1 second began their recovery until reaching, and even exceeding, their baseline values at 7 years. Diffusing capacity of the lungs for carbon monoxide and ventilation/perfusion scans continued to reduce for 24 months and then partially recovered their baseline values (-3.5%, -3.8%, and -5.5%, respectively). Only the percentage difference at 7 years in the ventilation scan correlated with the dosimetric parameters studied. Other variables, such as age, smoking status, previous chemotherapy, and concomitant tamoxifen showed no significant relation with changes in PFT (ΔPFT) values at 7 years. The study of reproducible subclinical parameters, such as PFT values, shows how their figures decrease in the first 2 years but practically recover their baseline values in the long term. The extent of the reduction in PFT values was small, and there was no clear association with several dosimetric and clinical parameters.

Quantitative Computed Tomographic Indexes in Diffuse Interstitial Lung Disease

To assess the correlation among quantitative indexes of computed tomography (CT), spirometric pulmonary function tests (PFTs), and visual scores (VSs) of CT in patients with diffuse interstitial lung disease (DILD) and to prove the estimated value of CT quantification for the prediction of the possibility of pulmonary function impairment. A total of 157 patients (male to female ratio, 96:61; mean age, 63 ± 11 years) with DILD were enrolled in this study. All patients underwent volume thin-section CT in the supine position at full inspiration. During the same period, 23 people (male to female ratio, 10:13; mean age, 55 ± 13 years) with no history of DILD and with normal PFTs and CT findings were used as a control group. Quantitative indexes were obtained using a commercial CAD system (Brilliance Workspace v3.0; Philips Medical Systems). Quantitative indexes included total lung volume (TLV), mean lung attenuation, variation of lung attenuation, emphysema volume (<-950 Hounsfield units [HU]), functioning lung volume (-700 HU > pixel > -950 HU), and interstitial lung disease volume (>-700 HU). Visual scores were measured semiquantitatively and included the overall extent of pulmonary parenchymal abnormality as well as the extent of consolidation, ground glass opacity, reticulation, and honeycomb opacities. Quantitative indexes were correlated with PFT and VSs using the Pearson correlation test. Quantitative indexes, PFT results, and VSs differed significantly between the DILD group and the control group, except for emphysematous parameters (P < 0.05).Pulmonary function test results showed significant correlation with quantitative indexes in the DILD group. Functioning lung volume showed positive correlation with forced vital capacity and forced expiratory volume in 1 second (r = 0.80 and 0.73, P < 0.001). Total lung capacity showed positive correlation with TLV (r = 0.83, P < 0.001).Visual scores were correlated with the ratio of a specific volume to TLV (indicated as ®). Interstitial lung disease volume® showed positive correlation (r = 0.53, P < 0.001), and FLV® showed a negative correlation with the overall extent of ILD (r = -0.52, P < 0.001). variation of lung attenuation showed a positive correlation with honeycombing extent (r = 0.37, P < 0.001), and mean lung attenuation showed a positive correlation with reticulation extent (r = 0.42, P < 0.001). Quantitative indexes measured by a commercial workstation showed good correlation not only with the extent of DILD estimated by visual inspection but also with PFT results. Quantitative indexes can be used as an objective tool for quantitative evaluation of disease extent and for follow-up of the progression or improvement of a DILD.

Evaluation of forced expiratory volume prediction in spirometric test using Principal Component Analysis

In this work, an attempt has been made to evaluate the clinical relevance of lung function spirometric test using neural network based prediction and Principal Component Analysis (PCA). Flow–volume curves generated using spirometer on subjects (N = 175) under standard recording protocol were used for the present study. The most significant spirometric parameter FEV1 predicted using Radial basis function neural networks (RBFNN) incorporating k – means clustering method was considered further for analysing the interdependency of spirometric parameters. PCA was performed on the measured and predicted datasets to analyse the interdependency among the parameters. Results demonstrate that PCA confirms the consistency in prediction of FEV1 for normal subjects. It appears that this method of prediction and principal component analysis could be useful in explaining the significance of FEV1 in assessing the lung function abnormalities for spirometric pulmonary function test with incomplete data.

Spirometric Pulmonary Function Test in Preschool Children

Children aged 3~5 years old represent the challenge in pulmonary function assessment, since evaluating lung function in preschool age group is important for the appropriate treatment for patient with chronic and recurrent cough and wheeze during this period. The joint American Thoracic Society/European Respiratory Society task force has produced recommendations for the spirometric lung function test currently used in the preschool age group. The reliable scientific evidence, documented references and reviews by the experts were used as a support. Reference data of spirometry lung function in preschool children were available in several countries including USA, Norway, Czech, Israel, Canada, and Taiwan. Spirometric pulmonary function tests are feasible in 3~ to 5~year~old children. However, the existing data are not sufficient to make definitive recommendations. Recommendations will need to be revised periodically until sufficient evidence has been collected to make definitive guidelines in various situations.

Evaluation of Flow–Volume Spirometric Test Using Neural Network Based Prediction and Principal Component Analysis

In this work, an attempt has been made to enhance the diagnostic relevance of spirometric pulmonary function test using neural networks and Principal Component Analysis (PCA). For this study, flow-volume curves (N = 175) using spirometers were generated under standard recording protocol. A method based on neural network is used to predict the most significant parameter, FEV(1). Further, PCA is used to analyze the interdependency of the parameters in the measured and predicted datasets. Results show that the back propagation neural network is able to predict FEV(1) both in normal and abnormal cases. The variation in the magnitude and direction of parameters in the contribution of the principal components shows that FEV(1) is a significant discriminator of normal and abnormal datasets and is further confirmed by the percentage variance in the first few principal components. It appears that this method of prediction and principal component analysis on the measured and predicted datasets could be useful for spirometric pulmonary function test with incomplete data.