Screening for bronchiectasis. A comparative study between chest radiography and high-resolution CT.

STUDY OBJECTIVE: The aim of our study was to investigate whether in the search for bronchiectasis a correlation exists between abnormalities on the chest radiograph and high-resolution CT (HRCT), and if HRCT has an additional value when the chest radiography is normal. SUBJECTS AND METHODS: In a prospective study, chest radiographs were compared with HRCT in 84 patients. Analysis of presence and extent of bronchiectasis were made for each bronchopulmonary lobe. RESULTS: Thirty-seven patients had a normal radiograph, from whom 32 had a normal HRCT. The other 5 had a low HRCT severity score with a mild cylindrical bronchiectasis. From the 47 patients with an abnormal radiograph, 36 had signs of bronchiectasis at HRCT; 11 patients, however, had a normal HRCT. The sensitivity for chest radiography to detect bronchiectasis appeared to be 87.8% with a specificity of 74.4%. We found a significant linear relationship between the severity of bronchiectasis at HRCT and abnormalities as seen on the chest radiograph (r=0.62, p=0.0001). CONCLUSION: A normal chest radiograph almost always excludes relevant bronchiectasis and no further investigation seems necessary. There is a significant linear relationship between the severity of bronchiectasis at HRCT and abnormalities as seen on the chest radiograph.

Assessment of bronchiectasis: comparison of HRCT and spiral volumetric CT.

OBJECTIVE: Our goal was to ascertain the sensitivity of spiral CT for the detection of bronchiectasis in comparison with high resolution CT (HRCT). MATERIALS AND METHODS: Thirty-one patients with a suspected clinical diagnosis of bronchiectasis were evaluated with spiral CT (slice thickness 5 mm, pitch 1, reconstruction index 2 mm, 1 s rotation) and HRCT (1.5 mm, interval 10 mm). Analysis of the presence, type, and severity of bronchiectasis was performed for each bronchopulmonary lobe. RESULTS: In 30 patients, 177 lobes were evaluated. At HRCT 14 patients showed signs of bronchiectasis in 32 lobes. Spiral CT confirmed the presence in 29 lobes. In one lobe spiral CT was false positive. The severity score was the same in 23 lobes, in 4 lobes higher at HRCT, and in 2 lobes higher at spiral CT. Spiral CT has a high sensitivity of 91% to detect bronchiectasis with a specificity of 99.3%. Spiral CT demonstrates adequately lack of tapering of the bronchus. CONCLUSION: In patients with suspected bronchiectasis, HRCT is the method of first choice based on greater sensitivity and lower radiation dose. However, spiral CT done for other indications is a reliable method for assessment of bronchiectasis. Inability of patients to hold their breath did not prove to interfere with diagnostic reliability.

Radiation exposure in standard and high-resolution chest CT scans.

It has been suggested that radiation doses due to high-resolution computed tomography (HRCT) of the chest are considerably higher than those from conventional CT. We compared the effective dose (E, mSv) in conventional chest CT (10-mm contiguous slices) and HRCT (1.5-mm slices, gap 10 mm). In our study, the effective dose from a HRCT (0.98 mSv) is about 6.5 times less than the effective dose from a standard CT scan (6.5 mSv), and only a factor 12 higher than from a conventional chest examination (0.085 mSv).

[Bronchiectases; clinical aspects, diagnosis and treatment]. / Bronchiëctasieën; kliniek, diagnostiek en behandeling.

Localised bronchiectasis was diagnosed in three immigrants, a male aged 16 and two females aged 45 and 20 years old. The symptoms were productive coughing (purulent discharge) and (or) haemoptysis. All recovered after surgical resection of the diseased lung parts. With the growing population of immigrants in the Netherlands it is of great importance to consider the presence of localised bronchiectasis in patients from this population who present with a persistent or recurrent bronchopneumonia.

Variability of bronchodilator response and effects of inhaled corticosteroid treatment in obstructive airways disease. Dutch CNSLD Study Group.

BACKGROUND: In the day to day care of obstructive airways diseases (asthma and chronic obstructive pulmonary disease) important decisions such as disease classification and choice of therapy are based on assessment of the bronchodilator response. However, surprisingly little is known of the long term course of the bronchodilator response in patients with obstructive airways disease. METHODS: Data from a multicentre trial were used in which 274 patients aged 18-60 years with airways obstruction were selected with PC20 < 8 mg/ml and FEV1 < 95% CI of predicted. FEV1 was measured before and 20 minutes after 1000 micrograms terbutaline and 40 minutes after an additional 80 micrograms ipratropium bromide. Data were analysed from 185 patients who were followed up for 21 months (five measurements). Four different expressions of bronchodilator response (BDR) were examined for change under long term therapy, long term variability, and prognostic value in predicting response to inhaled corticosteroids. RESULTS: There was a significant reduction in BDR of 117 ml after three months of treatment with a beta 2 agonist plus a corticosteroid (BA + CS), but not after bronchodilators only. Significant reductions with BA + CS were also found in BDR as a percentage of initial FEV1, and in BDR as a percentage of predicted FEV1. Bronchodilator tests were quite variable (SD 186 ml or 11% of initial value) and less than half of the patients could consistently be classified as "irreversible" with recommended cutoff levels. The bronchodilator response at the start of the study proved to be a poor predictor of improvement in FEV1 under BA + CS treatment (correct prediction 60%). CONCLUSIONS: Bronchodilator responses decrease substantially with inhaled corticosteroid therapy, and within subject variability is considerable both in asthma and chronic obstructive pulmonary disease. Dichotomous decisions on whether patients are "irreversible" according to any single bronchodilator measurement should therefore be made with great caution. The bronchodilator response cannot be used accurately as a predictor of response to inhaled corticosteroids in obstructive airways disease.