支气管扩张症高分辨率CT与肺通气功能的相关性

目的 探讨支气管扩张症(简称支扩)高分辨率CT(HRCT)与肺通气功能的相关性.方法 纳入经胸部HRCT诊断的支扩稳定期患者40例.根据CT评分系统对其胸部CT进行评分,并进行肺通气功能检查.结果 CT评分显示,支扩分布范围、扩张程度、管壁厚度分别为:(7.098±4.918)分、(6.540±4.113)分、(4.405±2.477)分.肺通气功能指标:FEV1占预计值%(FEVl%pred)为(56.122±26.335)%,FVC占预计值%(FVC%pred)为(66.857±21.951)%,FEV1/FVC为(64.612±14.890)%.支扩分布范围与FEV1 oApred、FVC%pred、FEV1/FVC均呈明显负相关(r=-0.451～-O.571,P值均<0.01).扩张程度、管壁厚度与FEV1%pred、FVC%pred、FEV1/FVC均无相关性.结论 支扩的分布范围与肺通气功能密切相关.     

Expiratory computed tomography for assessment of suspected pulmonary emphysema

Results of computed tomography of the lung performed at two levels in upper lung zones at full inspiration and full expiration were compared with results of tests of ventilatory function, lung mechanics, and single breath carbon monoxide diffusing capacity in 64 subjects, many of whom had some form of airflow obstruction. From the CT scans, the mean percentage of pixels in the range -900 to -1,024 Hounsfield units, or pixel index, was determined for each subject. The highest correlations of pixel index with physiologic variables consistent with a diagnosis of emphysema were observed for CT taken at full expiration. In some subjects, the inspiratory CT would give a "false positive" for emphysema when the hyperaeration observed at inspiration was not observed at expiration. We believe that the CT scan taken at full expiration can effectively reveal the abnormal permanent enlargement of airspaces which defines emphysema and provides a noninvasive method of assessing lung morphology in the living human subject.     

Quantitative assessment of pulmonary function in lymphangioleiomyomatosis patients using high-resolution computed tomography and pulmonary function tests

BackgroundTo explore the feasibility of using quantitative high-resolution computed tomography (HRCT) to evaluate pulmonary function in patients with pulmonary lymphangioleiomyomatosis (PLAM).MethodsPulmonary function tests (PFTs) were performed in 30 patients with pathologically confirmed PLAM with the use of HRCT. These results were correlated with quantitative HRCT in 21 patients.ResultsThere were significant correlations between the HRCT parameters for lung function and PFT parameters. Among these parameters, emphysema volume (EV), pulmonary volume with a pixel index less than the trigger threshold (−950 HU) to account for a proportion of total lung volume [PI-950 (%)] and forced expiratory volume in 1 second/forced vital capacity [FEV1/FVC (%)] had the strongest correlations, reaching values between −0.71 and −0.68. HRCT lung function might therefore also be helpful for predicting changes in lung function before and after treatment.ConclusionsHRCT is helpful for the assessment of pulmonary function in PLAM patients and can assist in the clinical evaluation of lung function and treatment response in patients with this disease.     

Emphysema in silicosis. A comparison of smokers with nonsmokers using pulmonary function testing and computed tomography

The presence of emphysema in silicosis is believed to be secondary to the development of progressive massive fibrosis (PMF). However, it is difficult to separate out other causative factors, particularly cigarette smoking. In order to attempt to distinguish these factors, we examined 30 patients with silicosis by means of pulmonary function testing and computed tomography (CT) scans of the chest. Eighteen of these patients were either exsmokers or current smokers, and 12 of them were nonsmokers. The CT scans were read independently by two observers on two separate occasions. Silicosis was graded on a 5-point scale from 0 to 4; emphysema was graded as a percentage of lung involved. Percent emphysema was associated with level of pulmonary function (FEV1, FVC, and DLCO) independent of its association with either cigarette smoking or silicosis grade (p less than 0.01). Silicosis grade was associated with DLCO (p less than 0.05) independent of its association with either cigarette smoking or percent emphysema, but was not associated with level of FEV1 or FVC. In the group without PMF (silicosis Grade 0, 1, or 2), smokers had worse emphysema than nonsmokers (p less than 0.01); there was no such difference among the patients with PMF (silicosis Grade 3 or 4). Only one of the nonsmoking subjects with silicosis but without PMF had any emphysema detected on CT. Our data suggest that silicosis, in the absence of PMF, does not cause significant emphysema, and that it is primarily the degree of emphysema rather than the degree of silicosis that determines the level of pulmonary function.     

Comparison of pulmonary function and respiratory symptoms in water pipe and cigarette smokers

Background and objective: A major type of smoking in Middle Eastern countries is water pipe (WP) smoking. In the present study, pulmonary function tests (PFT) and respiratory symptoms (RS) were compared in WP smokers and deep inspiration (S‐DI) or normal inspiration (S‐NI) cigarette smokers. Methods: Pulmonary function and RS were compared among WP smokers, deep or normal inspiration cigarette smokers, and non‐smokers. Results: All PFT values in WP smokers and S‐DI, but only some values in S‐NI, were lower than those of non‐smokers (P < 0.05 to P < 0.001). In addition, all PFT values in WP smokers and S‐DI were lower than the corresponding values in S‐NI, except for forced expiratory volume in 1 s and maximal expiratory flow at 25% of forced vital capacity (P < 0.05 to P < 0.001). The prevalence of RS, except for sputum production, was greater in all three groups of smokers than in non‐smokers (P < 0.05 to P < 0.001). However, the severity of most RS in WP smokers and S‐DI, but only the severity of wheezing in S‐NI, was greater than that in non‐smokers (P < 0.05 to P < 0.01). There were inverse correlations for PFT values and positive correlations for RS, with duration and total amount of smoking (P < 0.05 to P < 0.001). Conclusions: The results from this study showed that there was a profound effect of WP smoking on PFT values and RS, which were similar to the effects of deep inspiration cigarette smoking.     

Role of quantitative chest perfusion computed tomography in detecting diabetic pulmonary microangiopathy

Aims

Aim of the study was to determine the role of perfusion chest computed tomography (pCT) in evaluation of pulmonary diabetic angiopathy.

Methods

18 never-smoking patients (10 diabetic patients and 8 healthy controls) underwent chest high resolution CT (HRCT) and then pCT scanning. In both groups, blood tests, biochemical analysis, fibrinogen, HbA_1c, spirometry, diffusion capacity for carbon monoxide (DLCO) and body pletysmography were performed.Following parameters of pulmonary perfusion have been analysed: blood volume (BV), blood flow (BF), mean transit time (MTT), time to peak (TTP) and permeability surface (PS).

Results

There were no statistically significant differences between groups in terms of age, sex, BMI, forced expiratory volume in one second (FEV₁), DLCO. Chest HRCT revealed no pathologies. Significantly higher values of chest pCT for BF (p = 0.05), BV (p = 0.05) and PS (p = 0.01) have been found in diabetics in comparison to controls. No differences were found in MTT.

Conclusions

Significant increase of perfusion parameters in diabetes seems to confirm pulmonary microangiopathy. The results indicate that further studies on application of pCT in diabetic patients may be beneficial for better understanding of lung microangiopathy, its diagnosing and monitoring.     

Quantitative computed tomography assessment of lung structure and function in pulmonary emphysema.

Accurate diagnosis and quantification of pulmonary emphysema during life is important to understand the natural history of the disease, to assess the extent of the disease, and to evaluate and follow-up therapeutic interventions. Since pulmonary emphysema is defined through pathological criteria, new methods of diagnosis and quantification should be validated by comparisons against histological references. Recent studies have addressed the capability of computed tomography (CT) to quantify pulmonary emphysema accurately. The studies reviewed in this article have been based on CT scans obtained after deep inspiration or expiration, on subjective visual grading and on objective measurements of attenuation values. Especially dedicated software was used for this purpose, which provided numerical data, on both two- and three-dimensional approaches, and compared CT data with pulmonary function tests. More recently, fractal and textural analyses were applied to computed tomography scans to assess the presence, the extent, and the types of emphysema. Quantitative computed tomography has already been used in patient selection for surgical treatment of pulmonary emphysema and in pharmacotherapeutical trials. However, despite numerous and extensive studies, this technique has not yet been standardized and important questions about how best to use computed tomography for the quantification of pulmonary emphysema are still unsolved.     

Small solid noncalcified pulmonary nodules detected by screening chest computed tomography

We aimed to determine the outcome of small (<10 mm) solid noncalcified pulmonary nodules detected by chest computed tomography (CT) scans. Reports of low-dose chest CT scans performed from October 2003 to April 2005 at the Seoul National University Hospital Healthcare System Gangnam Center were reviewed to identify patients with solid noncalcified pulmonary nodules smaller than 10 mm. Partly solid and nonsolid nodules or nodules without follow-up imaging within 1 year were excluded. Records were studied to determine if the initial nodules had changed in size. A total of 3478 chest CT examinations were performed, with 232 patients having small noncalcified nodules (6.7%). One hundred and thirty-eight patients met the criteria (104 men and 34 women) and 213 nodules were identified. The median age was 54 years (range 32-80) and at least 86 patients (62%) were at low to intermediate risk for developing lung cancer. The largest nodule was less than 5 mm in diameter in 87 patients (63%) and 5 mm or more in 51 patients (37%). None of the nodules grew and 29 (14%) decreased in size at follow-up CT scans performed within 12 months. When those individuals at low to intermediate risk for lung cancer were included, solid noncalcified subcentimeter nodules were less frequently found in low-dose CT screening and were nearly unchanged in size when a follow-up CT scan was done within 12 months.     

Maximal inspiratory pressure and inspiratory muscle endurance time in asthmatic children: Reproducibility and relationship with pulmonary function tests

Respiratory muscle strength, assessed by maximal inspiratory mouth pressure (P_i,max), and endurance, assessed as the length of time a subject could breathe against inspiratory resistance with a target mouth pressure ≥70% of P_i,max (T_lim), were measured in 20 symptomless asthmatic children, in order to assess the reproducibility of such measurements and their relationship to traditional pulmonary function tests or tests of bronchial hyperresponsiveness. After recording lung volumes and bronchial response to methacholine, P_i,max and T_lim were measured twice in the same morning, with a 30-minute interval between each experimental trial. Mean (±SD) values of P_i,max were 72.2 ± 20.6 cmH₂O in the first and 75.8 ± 22.9 cmH₂O in the second trial. T_lim was 154 ± 65 and 164 ± 66 seconds in the first and in the second trial respectively. A lack of agreement between different measurements was seen for both P_i,max and T_lim. The coefficient of repeatability was 24.8 for P_i,max and 92.3 for T_lim. A significant correlation between age and P_i,max as well as between body mass index and P_i,max were shown; no similar correlation was found for T_lim. No correlation was found between P_i,max and T_lim in either of the two successive runs or between either P_i,max or T_lim and lung volumes or bronchial response to methacholine. Our study shows that at this time the reproducibility of P_i,max or T_lim in children with asthma in remission seems to be poor, although P_i,max has a better reproducibility than T_lim. A standardized procedure to measure P_i,max, should be obtainable in the near future. This would improve its clinical usefulness since P_i,max is the only noninvasive test to assess respiratory muscle strength that can identify subjects at risk to develop respiratory muscle fatigue during an acute asthmatic attack. Pediatr. Pulmonol. 1997; 24:385–390. © 1997 Wiley-Liss, Inc.     

Hyperinflation in asthma and emphysema. Assessment by pulmonary function testing and computed tomography

To assess the role of emphysema on the hyperinflation in chronic asthma, we studied 20 subjects with irreversible airflow limitation. Ten of the subjects had asthma and had never smoked; the other ten were cigarette smokers. Pulmonary function testing and chest computed tomography (CT) scans were performed on all subjects. Emphysema was graded using a score based on the percentage of lung involved on CT scan. There was good inter- and intra-observer agreement for the emphysema scores. The median emphysema score was 0 percent in the nonsmoking group and 10 percent in the smoking group. All smokers with a total lung capacity (TLC) of greater than 120 percent predicted had evidence of emphysema on the CT scan. None of the asthmatic subjects with a TLC greater than 120 percent predicted had emphysema identifiable on CT scan. We conclude that chronic asthma with severe hyperinflation does not result in emphysema.     

Longitudinal change during follow-up of systemic sclerosis: correlation between high-resolution computed tomography and pulmonary function tests

Clinical Rheumatology - The objective of this study was to determine the correlation between functional and radiological longitudinal change in patients with systemic sclerosis–associated...     

Liver function tests in patients with computed tomography demonstrated hepatic metastases

One hundred patients with computed tomographic (CT) evidence of liver metastases (and confirmation by biopsy or progression of disease) had serum levels of alkaline phosphatase, serum glutamic oxaloacetic transaminase, and serum glutamic pyruvic transaminase measured within two weeks of scanning. All three enzymes were within the normal range in 33% of patients. Even with advanced involvement (defined as three or more metastatic lesions over 3 cm in diameter), 20% of patients had normal levels of all three liver enzymes. Although liver function tests (LFTs) (enzyme levels) are inexpensive and simple to perform, they failed to detect a significant number of patients with liver metastases.     

Pulmonary function tests versus computed tomography in sheep with experimental emphysema

The authors explored the relative utility of pulmonary function tests (PFTs) and computed tomography (CT) to characterize the progression of papain induced emphysema in sheep (n = 12). PFT included plethysmography (FRC(pleth)), helium dilution (FRC(He)), and expired reserve volume (ERV). Following papain, FRC(pleth) and FRC(He) were unchanged; ERV decreased hence residual volume increased significantly (RV + 270 mL, +86%, P = .02). In contrast, FRC by CT increased in 10 of 12 sheep (+264 mL +21%, P = .008). We conclude that plethysmography was insensitive to emphysema, but the effect on ERV (i.e., trapped gas volume) and FRC by CT were very similar, and in line with the morphologic changes in this animal model.     

Values of high-resolution computed tomography and pulmonary function tests in managements of patients with chronic hepatitis C virus infection

AIM: To investigate pulmonary involvement via pulmonary function tests (PFT) and high-resolution computed tomography (HRCT) in patients with chronic hepatitis C virus (HCV) infection. METHODS: Thirty-four patients with chronic HCV infection without diagnosis of any pulmonary diseases and 10 healthy cases were enrolled in the study. PFT and HRCT were performed in all cases. RESULTS: A decrease lower than 80% of the predicted value was detected in vital capacity in 9/34 patients, in forced expiratory volume in one second in 8/34 patients, and in forced expiratory flow 25-75 in 15/34 patients, respectively. Carbon monoxide diffusing capacity (DLCO) was decreased in 26/34 patients. Findings of interstitial pulmonary involvement were detected in the HRCT of 16/34 patients. Significant difference was found between controls and patients with HCV infection in findings of HRCT (chi2=4.7, P=0.003). Knodell histological activity index (KHAI) of 28/34 patients in whom liver biopsy was applied was 9.0+/-4.7. HRCT findings, PFT values and DLCO were not affected by KHAI in patients with HCV infection. In these patients, all the parameters were related with age. CONCLUSION: We suggest that chronic hepatitis C virus infection may cause pulmonary interstitial involvement without evident respiratory symptoms.     

High resolution computed tomography and lung function in asbestos-exposed workers with normal chest radiographs

Asbestos-exposed persons with normal chest radiographs can demonstrate parenchymal abnormalities on high resolution computed tomography (HRCT). We reviewed the HRCT, clinical presentation, and results of pulmonary function tests in 169 asbestos-exposed workers with normal chest radiographs (ILO less than 1/0). The HRCT was normal or near normal in 76 subjects (Group 1), abnormal but indeterminate for asbestosis in 36, and abnormal and suggestive of asbestosis in 57 (Group 2). The indeterminate subjects were excluded from further analysis. The subjects in Groups 1 and 2 were not significantly different in their duration of asbestos exposure, latency, smoking history, or in measurements of airflow obstruction (FEV1/FVC% and %FEV1). Both the vital capacity percent predicted and diffusing capacity percent predicted were significantly lower in the abnormal subjects (Group 2) than in the normal subjects (Group 1) (79.0 versus 86.2, p = 0.005; 78.2 versus 87.1, p = 0.024; independent t test). We conclude that in asbestos-exposed subjects with normal chest radiographs, HRCT can identify a group of subjects with significantly reduced lung function indicative of restrictive lung disease when compared with a group with normal or near-normal HRCT.