High-resolution CT Scores Research Articles

Acute exacerbation of idiopathic pulmonary fibrosis: high-resolution CT scores predict mortality

To determine high-resolution computed tomography (HRCT) findings helpful in predicting mortality in patients with acute exacerbation of idiopathic pulmonary fibrosis (AEx-IPF). Sixty patients with diagnosis of AEx-IPF were reviewed retrospectively. Two groups (two observers each) independently evaluated pattern, distribution, and extent of HRCT findings at presentation and calculated an HRCT score at AEx based on normal attenuation areas and extent of abnormalities, such as areas of ground-glass attenuation and/or consolidation with or without traction bronchiectasis or bronchiolectasis and areas of honeycombing. The correlation between the clinical data including the HRCT score and mortality (cause-specific survival) was evaluated using the univariate and multivariate Cox-regression analyses. Serum KL-6 level, PaCO(2), and the HRCT score were statistically significant predictors on univariate analysis. Multivariate analysis revealed that the HRCT score was an independently significant predictor of outcome (hazard ratio, 1.13; 95% confidence interval, 1.06-1.19, P = 0.0002). The area under receiver operating characteristics curve for the HRCT score was statistically significant in the classification of survivors or nonsurvivors (0.944; P < 0.0001). Survival in patients with HRCT score ≥245 was worse than those with lower score (log-rank test, P < 0.0001). The HRCT score at AEx is independently related to prognosis in patients with AEx-IPF.

Prognostic factors in rapidly progressive interstitial pneumonia

Clinical and other features, as well as prognostic factors for survival, were examined in patients with rapidly progressive interstitial pneumonia. The disease entity included different histological patterns with diverse outcomes, and distinctions were not possible from baseline data. Histological diagnosis was the only significant prognostic determinant. The aim of the present study was to examine clinical and other features that might allow prognostic distinctions between histological patterns in presentations with rapidly progressive interstitial pneumonia (RPIP), and to assess prognostic factors for survival. Patients with RPIP among 425 consecutive patients with diffuse lung disease, who underwent surgical lung biopsy, were studied retrospectively. The discriminatory value of clinical and investigative features for identifying disease with a better outcome was evaluated. An a priori comparison was made between diffuse alveolar damage (DAD)/usual interstitial pneumonia with DAD pattern (Group A), and organizing pneumonia/non-specific interstitial pneumonia pattern (Group B). Twenty-eight patients (6.6%) fulfilled the criteria for RPIP. The diagnosis was Group A disease in 15 (DAD in 10, usual interstitial pneumonia with DAD in 5), and Group B disease in 13 (organizing pneumonia in 8, non-specific interstitial pneumonia in 5). There were no significant differences in initial findings between the groups. Prognosis was significantly better for Group B patients than for Group A patients (P=0.021). Neither BAL nor parenchymal high-resolution CT score was indicative of therapeutic responsiveness or outcome. Distinction between Group A and Group B on the basis of disease pattern was the only significant determinant of prognosis. RPIP included varied histological patterns with different outcomes, and in many cases these could not be predicted using baseline clinical data. Histology was the only significant predictor of ultimate prognosis.

Neonatal bronchopulmonary dysplasia predicts abnormal pulmonary HRCT scans in long-term survivors of extreme preterm birth

Background:There is an increasing understanding that extreme preterm birth carries a risk of long-term pulmonary sequelae. A study was undertaken to investigate if, and in what way, neonatal factors were...

Pulmonary Abnormalities on High-Resolution CT Demonstrate More Rapid Decline Than FEV1 in Adults With Cystic Fibrosis

FEV1 may remain stable while high-resolution CT (HRCT) appearances deteriorate in children with cystic fibrosis (CF). However, spirometry results commonly decline in older age groups. To compare the rate of decline in HRCT abnormalities and spirometry results over time in an adult cohort with CF. The HRCT scans of 39 consecutive patients (19 males and 20 females; mean age, 22 years; range, 16 to 48 years) with two HRCT scans > 18 months apart were randomly and blindly scored using a modified Bhalla scoring system by two independent chest radiologists. Age, body mass index, spirometry, and sputum cultures were recorded at the time of both HRCTs. Rates of change in clinical parameters and HRCT abnormalities were calculated and compared using repeated-measures analysis of variance. Mean FEV1 declined at a rate of - 2.3% per year, while mean HRCT total score declined at a rate of -2.7% per year. Several individual HRCT abnormalities as well as HRCT total scores declined significantly faster than FEV1 (p < 0.001). Six patients showed stable spirometry results but worsening HRCT scores. Mucus plugging and extent of bronchiectasis deteriorated at a more rapid rate in the group with mildly impaired lung function. Air trapping, collapse/consolidation, peribronchial thickening, severity of bronchiectasis, and generations of bronchial divisions involved deteriorated at a more rapid rate in the group with moderate-to-severely impaired lung function. Adult CF patients have more rapid rates of decline in HRCT abnormalities than in spirometry results. Individual HRCT abnormalities decline at different rates depending on the degree of lung function impairment.

Lung Structure Abnormalities, But Normal Lung Function in Pediatric Bronchiectasis

Bronchiectasis is not considered to be uncommon in children anymore. The relationship between pulmonary function and severity of bronchiectasis is still controversial. To assess the extent and severity of bronchiectasis through high-resolution CT (HRCT) scan score, and to correlate it with clinical, microbiological, and functional data. Forty-three white children with HRCT-diagnosed bronchiectasis were studied. Bronchiectasis extent, bronchial wall thickening severity, and bronchial wall dilatation severity were evaluated using the Reiff score. Clinical, microbiological, and spirometry results were related to total HRCT scan score and to subscores as well. The percentages of affected lobes were as follows: right lower lobe, 65%; middle lobe, 56%; left lower lobe, 51%; right upper lobe, 37%; lingula, 30%; and left upper lobe, 30% (chi(2) = 18.4; p = 0.002). The mean (+/- SEM) HRCT score was 20 +/- 2.6. Total score or subscores of bronchiectasis extent, bronchial wall thickening severity, and bronchial wall dilatation severity were not significantly related to FEV(1) and FVC. Seventy-four percent of patients had asthma. The age at the onset of cough correlated with age at the time of the HRCT scan (p = 0.004) and with the presence of asthma (p = 0.01). Positive findings of deep throat or sputum cultures were found more frequently in atopic patients (p = 0.02) and asthmatic (p < 0.01) patients, and in children who were < 2 years of age at the onset of cough (p < 0.01). Normal lung function may coexist with HRCT scan abnormalities and does not exclude damage to the bronchial structure. Pulmonary function is not an accurate method for assessing the severity of lung disease in children with bronchiectasis.

Inflammatory activity is still present in the advanced stages of idiopathic pulmonary fibrosis

The role of active inflammation in idiopathic pulmonary fibrosis (IPF) is controversial. A gallium-67 citrate (Ga(67) scan) is a sensitive indicator of inflammatory activity. The aim of this study was to assess the Ga(67) uptake and other markers of inflammation at different stages of IPF and to investigate its prognostic role. Twenty-two patients (aged 66 +/- 11 years, 18 males) with IPF were monitored for a period of 6-20 months (mean 13 months). At presentation (T0), high resolution CT (HRCT) scans showed reticular opacities and traction bronchiectasis with bi-basilar and peripheral distribution in all cases. At both T0 and follow-up (T1), we measured pulmonary function (PaO(2), FVC, DLco), overall radiographic extent of fibrosis (HRCT visual score), Ga(67) uptake, serum concentrations of lactate dehydrogenase (LDH) and C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR). All parameters showed a significant deterioration during the T0-T1 interval, though the increase in Ga(67) uptake and serum markers was not significant. Patients with Ga(67) uptake indices graded as normal or mildly increased (group I), and graded as considerably or severely increased (group II) at presentation, were compared. There was no significant difference with respect to lung function or HRCT score between the two groups at T1. Ga(67) uptake, LDH, CRP and ESR at presentation did not correlate significantly with the interval change in pulmonary function and disease extent. Our findings indicate that inflammatory activity in the advanced stage of IPF is still relevant, although a Ga(67) scan is not predictive of the clinical course.

Dornase Alfa Reduces Air Trapping in Children With Mild Cystic Fibrosis Lung Disease: A Quantitative Analysis

To evaluate quantitative air trapping measurements in children with mild cystic fibrosis (CF) lung disease during a 1-year, double-blind, placebo-controlled, recombinant human deoxyribonuclease (rhDNase) [dornase alfa] intervention trial and compare results from quantitative air trapping with those from spirometry or visually scored high-resolution CT (HRCT) scans of the chest.Twenty-five children with CF randomized to either daily rhDNase or placebo aerosol were evaluated at baseline, and at 3 months and 12 months by spirometer-triggered HRCT and spirometry. Outcome variables were percentage of predicted FVC, FEV1, and forced expiratory flow, midexpiratory phase (FEF(25-75%)); total and subcomponent visual HRCT scores; and quantitative air trapping measurements derived from chest HRCT images.At baseline, there were no statistical differences between groups in any of the variables used as an outcome. After 3 months of treatment, both groups had improvements in percentage of predicted FEV1 and FEF(25-75%), and total HRCT visual scores. In contrast, the rhDNase group had a 13% decrease in quantitative air trapping from baseline (severe air trapping [A3]), compared to an increase of 48% in the placebo group (p = 0.023). After 12 months, both groups had declines in percentage of predicted FVC and FEV1, but the rhDNase group retained improvements in percentage of predicted FEF(25-75%) and quantitative air trapping. The mucus plugging and total HRCT visual scores were also improved in the rhDNase group after 12 months of treatment, with and without significant differences between groups (p = 0.026 and p = 0.676). Quantitative air trapping (A3) remained improved in the rhDNase group (- 15.4%) and worsened in the placebo group (+61.3%) with nearly significant differences noted between groups (p = 0.053) after 12 months of treatment.Quantitative air trapping is a more consistent sensitive outcome measure than either spirometry or total HRCT scores, and can discriminate differences in treatment effects in children with minimal CF lung disease.

Pulmonary Sarcoidosis: Comparison of Findings of Inspiratory and Expiratory High-Resolution CT and Pulmonary Function Tests Between Smokers and Nonsmokers

The purpose of our study was to compare the high-resolution CT and pulmonary function test findings of smokers and nonsmokers with pulmonary sarcoidosis. Full inspiratory and expiratory high-resolution CT of the thorax and pulmonary function tests were performed in 46 patients (23 smokers and 23 lifelong nonsmokers) with histologically proven sarcoidosis. The median interval between high-resolution CT and pulmonary function tests was 8 days (range, 0-27 days). High-resolution CT findings were categorized into six patterns, and the overall extent of each pattern was scored independently (high-resolution CT score). Correlation between each high-resolution CT score with each pulmonary functional parameter was performed using Spearman's rank correlation and stepwise multiple regression analysis. Air trapping on expiration (45/46 patients, 98%) and small nodules on inspiration (all 46 patients, 100%) were the most common findings. Smokers had a greater extent of emphysema than nonsmokers (p = 0.002). No significant difference was seen in the extent of air trapping, consolidation, ground-glass attenuation, reticular opacities, or small nodules between smokers and nonsmokers. On Spearman's rank correlation, the extent of air trapping negatively correlated with forced vital capacity in smokers (p < 0.05) but not in nonsmokers. The extent of small nodules negatively correlated with forced vital capacity and positively correlated with the ratio of forced expiratory volume in 1 sec to forced vital capacity in nonsmokers (p < 0.05, both) but not in smokers, respectively. On stepwise multiple regression analysis, the extent of air trapping on CT was independently associated with decreased forced vital capacity (p < 0.05), and cigarette smoking was the main determinant of decrease in maximum midexpiratory flow and forced expiratory flow at 50% of vital capacity (p < 0.01). Cigarette smoking confounds the correlation between the CT and pulmonary function test findings in patients with sarcoidosis. Therefore, smoking history must be taken into account when correlating the extent of parenchymal sarcoidosis on CT with functional impairment.

Correlation of High-Resolution CT, Symptoms, and Pulmonary Function in Patients During Recovery From Severe Acute Respiratory Syndrome

Study objectives:Little is known of the nature of the recovery period after severe acute respiratory syndrome (SARS) infection. We hypothesized that structural changes of the lung might correlate with symptoms and pulmonary function. To answer this question, we correlate findings of high-resolution CT (HRCT) with dyspnea scores and results of pulmonary function tests in patients during recovery from SARS.Design:Retrospective follow-up cohort study.Setting:University hospital.Patients:Nineteen patients who recovered from SARS-related hospitalization.Measurements:The study included HRCT scores (0 to 100), dyspnea scores (1 to 4), static and dynamic lung volumes, and diffusing capacity of the lung for carbon monoxide (Dlco).Results:The interval between hospital discharge and HRCT study or functional assessment was 31.2 ± 4.8 days (range, 25 to 38 days) [mean ± SD]. All patients had HRCT abnormalities and were assigned to two groups: ground-glass opacity (GGO) only (n = 7, 36.8%) and GGO with fibrosis (GGO+F) [n = 12, 63.2%]. Most patients (16 of 19, 84.2%) had no zonal predominance. HRCT scores correlated well with dyspnea scores (r = 0.78, p < 0.01) and with a variety of pulmonary functional variables, with Dlco being the most significant (r = − 0.923, p < 0.001). Compared with the GGO group, the GGO+F group showed significantly lower FEV1, FVC, total lung capacity, residual volume, and Dlco.Conclusions:HRCT findings correlate well with functional studies and clinical symptoms during recovery from SARS. Longer-term follow-up studies in a larger cohort of patients should be performed to investigate the clinical outcome of recovered SARS patients.

Interstitial Lung disease in Systemic Sclerosis. An HRCT-clinical correlative study

To evaluate high-resolution CT (HRCT) parameters of inflammation and fibrosis in systemic sclerosis (SSc), for correlation with lung function, skin scores and exercise tolerance. 45 SSc patients (40 women, 48.5+/-13.4 years), underwent thoracic HRCT, lung function assessment, and modified Rodnan skin scores. Exercise tolerance was also graded. HRCT were scored for extent of 4 HRCT patterns of interstitial lung disease (ILD): ground glass opacification (GGO), reticular, mixed and honeycomb pattern in each lobe. Total HRCT score, inflammation index (GGO and mixed score) and fibrosis index (reticular and honeycomb scores) were correlated with lung function and clinical parameters. ILD was present in 39/45 (86.7%) patients. Abnormal (<80% predicted) forced vital capacity (FVC), total lung capacity (TLC) and carbon monoxide diffusion factor (DLco) were detected in 30%, 22% and 46% of patients. Total HRCT score correlated with FVC (r=-0.43, p=0.008), FEV1 (forced expiratory volume) (r=-0.37, p=0.03), TLC (r=-0.47, p=0.003), and DLCO (r=-0.43, p=0.008); inflammatory index with DLCO (r=-0.43, p=0.008) and exercise tolerance (r=-0.39, p < 0.05); and fibrosis index with FVC (r=-0.31, p=0.05) and TLC (r=-0.38, p=0.02). Higher total HRCT score, and inflammation and fibrosis indices were found in patients with abnormal lung function. Qualitative HRCT is able to evaluate inflammation and fibrosis, showing important relationships with diffusion capacity and lung volume, respectively.

Interstitial lung disease in systemic sclerosis.

To evaluate high-resolution CT (HRCT) parameters of inflammation and fibrosis in systemic sclerosis (SSc), for correlation with lung function, skin scores and exercise tolerance. 45 SSc patients (40 women, 48.5+/-13.4 years), underwent thoracic HRCT, lung function assessment, and modified Rodnan skin scores. Exercise tolerance was also graded. HRCT were scored for extent of 4 HRCT patterns of interstitial lung disease (ILD): ground glass opacification (GGO), reticular, mixed and honeycomb pattern in each lobe. Total HRCT score, inflammation index (GGO and mixed score) and fibrosis index (reticular and honeycomb scores) were correlated with lung function and clinical parameters. ILD was present in 39/45 (86.7%) patients. Abnormal (<80% predicted) forced vital capacity (FVC), total lung capacity (TLC) and carbon monoxide diffusion factor (DLco) were detected in 30%, 22% and 46% of patients. Total HRCT score correlated with FVC (r=-0.43, p=0.008), FEV1 (forced expiratory volume) (r=-0.37, p=0.03), TLC (r=-0.47, p=0.003), and DLCO (r=-0.43, p=0.008); inflammatory index with DLCO (r=-0.43, p=0.008) and exercise tolerance (r=-0.39, p < 0.05); and fibrosis index with FVC (r=-0.31, p=0.05) and TLC (r=-0.38, p=0.02). Higher total HRCT score, and inflammation and fibrosis indices were found in patients with abnormal lung function. Qualitative HRCT is able to evaluate inflammation and fibrosis, showing important relationships with diffusion capacity and lung volume, respectively.

Emphysema in heavy smokers with normal chest radiography. Detection and quantification by HRCT

Purpose: To determine the severity and extent of emphysema in heavy smokers by high-resolution CT (HRCT) and to correlate the findings with spirometric tests (STs) and symptomatology. Material and Methods: Fifty adult smokers with a mean age of 53 years with a smoking history of more than 30 pack years and normal chest radiographs underwent HRCT of the chest and ST (FEV1, FEV1/FVC, PEFR). Among these, 22 had symptoms of pulmonary disease and 28 were asymptomatic. Quantification of emphysema was done using a density mask program and the visual scoring method. The results were correlated with ST and symptomatology. Results: 58% (29 out of 50) of the subjects had significant emphysema on HRCT. Eleven out of 15 with normal ST showed emphysema on HRCT while 2 with airflow obstruction on ST showed normal CT scores. 14% (4 out of 28) asymptomatic subjects had severe emphysema compared to 64% of symptomatic subjects. Emphysematous changes were predominantly seen in upper lung zones in 48% of the patients while in 52% it was distributed equally in both upper and lower zones. The number of pack years of smoking showed a positive correlation with CT scores. The correlation between HRCT scores and ST was statistically significant. Conclusion: A significant number of asymptomatic and clinically undiagnosed smokers tend to have significant emphysema. HRCT helps in early detection of disease and thus helps implementation of preventive measures.

Emphysema in heavy smokers with normal chest radiography. Detection and quantification by HCRT.

To determine the severity and extent of emphysema in heavy smokers by high-resolution CT (HRCT) and to correlate the findings with spirometric tests (STs) and symptomatology. Fifty adult smokers with a mean age of 53 years with a smoking history of more than 30 pack years and normal chest radiographs underwent HRCT of the chest and ST (FEV1, FEV1/FVC, PEFR). Among these, 22 had symptoms of pulmonary disease and 28 were asymptomatic. Quantification of emphysema was done using a density mask program and the visual scoring method. The results were correlated with ST and symptomatology. 58% (29 out of 50) of the subjects had significant emphysema on HRCT. Eleven out of 15 with normal ST showed emphysema on HRCT while 2 with airflow obstruction on ST showed normal CT scores. 14% (4 out of 28) asymptomatic subjects had severe emphysema compared to 64% of symptomatic subjects. Emphysematous changes were predominantly seen in upper lung zones in 48% of the patients while in 52% it was distributed equally in both upper and lower zones. The number of pack years of smoking showed a positive correlation with CT scores. The correlation between HRCT scores and ST was statistically significant. A significant number of asymptomatic and clinically undiagnosed smokers tend to have significant emphysema. HRCT helps in early detection of disease and thus helps implementation of preventive measures.

High resolution CT in children with cystic fibrosis: correlation with pulmonary functions and radiographic scores

Objective: To compare the high resolution CT (HRCT) scores of the Bhalla system with pulmonary function tests and radiographic and clinical points of the Shwachman–Kulczycki clinical scoring system. Methods: HRCT of the chest was obtained in 40 children to assess the role of HRCT in evaluating bronchopulmonary pathology in children with cystic fibrosis (CF). The HRCT severity scores of the Bhalla system were compared with chest radiographic and clinical points of the Shwachman–Kulczycki scoring system and pulmonary function tests. Only 14 of the patients older than 6 years cooperated with spirometry. Results: HRCT scores correlated well with radiographic points ( r=0.80, P<0.0001) and clinical points ( r=0.67, P<0.0001) of the Shwachman–Kulczycki system, FVC ( r=0.71 P=0.004) and FEV 1 ( r=0.66, P=0.01). Although radiographic points correlated significantly with FVC ( r=0.61, P=0.02) and FEV 1 ( r=0.56, P=0.04), HRCT provides a more precise scoring than the chest X-ray. Conclusion: The HRCT scoring system may provide a sensitive method of monitoring pulmonary disease status and may replace the radiographic scoring in the Shwachman–Kulczycki system. It may be helpful especially in follow-up of small children too young to cooperate with spirometry

Pulmonary Function and High-Resolution CT Findings in Patients With an Inherited Form of Pulmonary Fibrosis, Hermansky-Pudlak Syndrome, Due to Mutations in HPS-1

To describe and correlate pulmonary function and high-resolution CT (HRCT) scan scores in individuals with a high risk for development of pulmonary fibrosis, ie, Hermansky-Pudlak syndrome (HPS) patients with mutations in the HPS-1 gene. Cross-sectional analysis of consecutive, eligible patients. Thirty-eight HPS inpatients at the National Institutes of Health Clinical Center with HPS-1 mutations. Thirty-seven patients were Puerto Rican and exhibited the typical 16-base pair (bp) duplication in exon 15 of HPS-1. One non-Puerto Rican was homozygous for a different mutation (intervening sequence 17 -2 A-->C) previously reported in the HPS-1 gene; he died at age 35 of pulmonary insufficiency. For the 23 patients who had pulmonary symptoms, the mean age of onset was 35 years. For all 38 patients (mean age, 37 +/- 2 years), the mean FVC was 71% of predicted; the mean FEV(1), 76%; mean total lung capacity (TLC), 72%; mean vital capacity (VC), 68%; and mean diffusing capacity of the lung for carbon monoxide (DLCO), 72%. When patients were grouped according to the extent of their reduction in FVC, the other four pulmonary function parameters followed the FVC. Seventeen patients had abnormal chest radiographs, and 31 (82%) had abnormal HRCT scans of the chest, for which a scoring system of 0 (normal) to 3 (severe fibrosis) is presented. The mean +/- SEM HRCT score for 38 patients was 1.30 +/- 0.17. HRCT scores correlated inversely with FVC and DLCO. Mutations in the HPS-1 gene, whether or not they involve the typical 16-bp duplication seen in Puerto Rican patients, are associated with fatal pulmonary fibrosis. In affected patients, the FVC, FEV(1), TLC, VC, and DLCO fall in concert, and this functional deficit correlates with HRCT scan evidence of progression of interstitial lung disease.

Relationship Between Abnormalities on High-Resolution CT and Pulmonary Function in Systemic Sclerosis

To determine the predictive value of abnormalities on high-resolution CT (HRCT) on pulmonary disease in systemic sclerosis. Fifty-two patients suffering from systemic sclerosis. Pulmonary disease was defined by pulmonary function test abnormalities, ie, total lung capacity (TLC) <80% of predicted value and/or diffusion of carbon monoxide (DLCO) <75% of predicted value, without any pulmonary event other than systemic sclerosis in the medical history. Patients were divided in two groups, group A with pulmonary disease (29 patients) and group B without pulmonary disease (23 patients). HRCT abnormalities were scored on whole lungs. A decision matrix was constructed to determine sensitivity, specificity, positive and negative predictive values, and false-positive and false-negative rates. A receiver operating characteristic curve was constructed to determine the best compromise between sensitivity and specificity. HRCT total scores were higher in group A (9.0+/-4.3) than in group B (5.0+/-2.8) (p < 0.001) and they correlated with TLC (r =-0.39, p < 0.005) and DLCO (r = -0.50, p < 0.0002). An HRCT score of 7 corresponded to the best compromise between sensitivity (0.60) and specificity (0.83), with a positive predictive value of 0.82. Taking into account a value of 10 for the HRCT score increased specificity to 1 but decreased sensitivity to 0.41. A minimum score of 7 would be required to consider HRCT abnormalities in systemic sclerosis as predictive of pulmonary disease. An HRCT score of 10 makes it possible to establish the diagnosis of lung involvement severe enough to impair pulmonary function.

High-resolution CT in the acute exacerbation of cystic fibrosis: evaluation of acute findings, reversibility of those findings, and clinical correlation.

The aims of this study were threefold: to compare high-resolution CT (HRCT) of adult patients with cystic fibrosis (CF) during acute exacerbations with asymptomatic patients with CF, to evaluate reversibility of HRCT abnormalities after exacerbations, and to correlate HRCT with clinical parameters. Nineteen symptomatic and eight asymptomatic patients were prospectively evaluated by HRCT and pulmonary function tests (PFTs). Symptomatic patients were reassessed 2 weeks after the exacerbation. Studies were independently reviewed by two radiologists using a modified Bhalla scoring system, noting the presence, extent, and severity of bronchiectasis, peribronchial thickening, mucus plugging, and atelectasis or consolidation. Modifications to the Bhalla system included evaluation of the presence and profusion of centrilobular nodules and air-fluid levels within bronchiectatic cavities. The highest possible score was 24 points. Higher scores indicated greater severity. Mosaic perfusion was noted but not included in the modified Bhalla HRCT score. Total modified Bhalla HRCT score and components of the HRCT score were correlated with corresponding PFT parameters. Bronchiectasis, peribronchial thickening, mucus plugging, centrilobular nodules, and mosaic perfusion were identified in symptomatic and asymptomatic patients. Air-fluid levels in bronchiectatic cavities, identified in two patients, represented the only finding limited to acute exacerbation. Reversible findings included air-fluid levels (100%), centrilobular nodules (36%), mucus plugging (33%), and peribronchial thickening (11%). Total HRCT severity scores of symptomatic and asymptomatic patients correlated with forced vital capacity (FVC) (r = .44, p = .01) and forced expiratory volume at 1 sec (FEV1) (r = .34, p = .04). Severity of bronchiectasis correlated with FVC (r = .50, p = .004) and FEV1 (r = .40, p = .02). Mucus plugging and centrilobular nodules did not correlate with PFT parameters. In the symptomatic patients, improvement in HRCT score correlated with changes in FEV1/FVC (r = .39, p = .049). Air-fluid levels in bronchiectatic cavities were the only parenchymal finding shown by HRCT that was limited to the acute exacerbation of CF in our study population. However, this finding was rare, being seen in two of 19 patients. Mucus plugging, centrilobular nodules, and peribronchial thickening were potentially reversible findings in symptomatic patients. HRCT accurately revealed disease severity in patients with CF. We also found that changes in HRCT scores correlated with clinical improvement as determined by PFTs.