Photon-counting computed tomography in the assessment of rheumatoid arthritis-associated interstitial lung disease: an initial experience

PURPOSE: Interstitial lung disease (ILD) accounts for a significant proportion of mortality and morbidity in patients with rheumatoid arthritis (RA). The aim of this cross-sectional study is to evaluate the performance of novel photon-counting detector computed tomography (PCD-CT) in the detection of pulmonary parenchymal involvement. METHODS: Sixty-one patients with RA without a previous definitive diagnosis of ILD underwent high-resolution (HR) (0.4 mm slice thickness) and ultra-high-resolution (UHR) (0.2 mm slice thickness) PCDCT examination. The extent of interstitial abnormalities [ground-glass opacity (GGO), reticulation, bronchiectasis, and honeycombing] were scored in each lobe using a Likert-type scale. Total ILD scores were calculated as the sum of scores from all lobes. RESULTS: Reticulation and bronchiectasis scores were higher in the UHR measurements taken compared with the HR protocol [median (quartile 1, quartile 3): 2 (0, 3.5) vs. 0 (0, 3), P < 0.001 and 2 (0, 2) vs. 0 (0, 2), P < 0.001, respectively]; however, GGO and honeycombing scores did not differ [2 (2, 4) vs. 2 (2, 4), P = 0.944 and 0 (0, 0) vs. 0 (0, 0), P = 0.641, respectively]. Total ILD scores from both HR and UHR scans showed a mild negative correlation in diffusion capacity for carbon monoxide (HR: r = -0.297, P = 0.034; UHR: r = -0.294, P = 0.036). The pattern of lung parenchymal involvement did not differ significantly between the two protocols. The HR protocol had significantly lower volume CT dose index [0.67 (0.69, 1.06) mGy], total dose length product [29 (24.48, 33.2) mGy*cm] compared with UHR scans [8.18 (6.80, 9.23) mGy, P < 0.001 and 250 (218, 305) mGy*cm, P < 0.001]. CONCLUSION: UHR PCD-CT provides more detailed information on ILD in patients with RA than low-dose HR PCDCT. HR PCD-CT image acquisition with a low effective radiation dose may serve as a valuable, low-radiation screening tool in the selection of patients for further, higher-dose UHR PCD-CT screening.

Artificial Intelligence-based CT Assessment of Bronchiectasis: The COPDGene Study.

Background CT is the standard method used to assess bronchiectasis. A higher airway-to-artery diameter ratio (AAR) is typically used to identify enlarged bronchi and bronchiectasis; however, current imaging methods are limited in assessing the extent of this metric in CT scans. Purpose To determine the extent of AARs using an artificial intelligence-based chest CT and assess the association of AARs with exacerbations over time. Materials and Methods In a secondary analysis of ever-smokers from the prospective, observational, multicenter COPDGene study, AARs were quantified using an artificial intelligence tool. The percentage of airways with AAR greater than 1 (a measure of airway dilatation) in each participant on chest CT scans was determined. Pulmonary exacerbations were prospectively determined through biannual follow-up (from July 2009 to September 2021). Multivariable zero-inflated regression models were used to assess the association between the percentage of airways with AAR greater than 1 and the total number of pulmonary exacerbations over follow-up. Covariates included demographics, lung function, and conventional CT parameters. Results Among 4192 participants (median age, 59 years; IQR, 52-67 years; 1878 men [45%]), 1834 had chronic obstructive pulmonary disease (COPD). During a 10-year follow-up and in adjusted models, the percentage of airways with AARs greater than 1 (quartile 4 vs 1) was associated with a higher total number of exacerbations (risk ratio [RR], 1.08; 95% CI: 1.02, 1.15; P = .01). In participants meeting clinical and imaging criteria of bronchiectasis (ie, clinical manifestations with ≥3% of AARs >1) versus those who did not, the RR was 1.37 (95% CI: 1.31, 1.43; P < .001). Among participants with COPD, the corresponding RRs were 1.10 (95% CI: 1.02, 1.18; P = .02) and 1.32 (95% CI: 1.26, 1.39; P < .001), respectively. Conclusion In ever-smokers with chronic obstructive pulmonary disease, artificial intelligence-based CT measures of bronchiectasis were associated with more exacerbations over time. Clinical trial registration no. NCT00608764 © RSNA, 2022 Supplemental material is available for this article. See also the editorial by Schiebler and Seo in this issue.

Chest CT-based Assessment of 1-year Outcomes after Moderate COVID-19 Pneumonia.

BACKGROUND: COVID-19 pneumonia may lead to pulmonary fibrosis in the long term. Chest CT is useful to evaluate changes in the lung parenchyma over time. PURPOSE: To illustrate the temporal change of lung abnormalities on chest CT scans associated with COVID-19 pneumonia over 1 year. MATERIALS AND METHODS: In this prospective study, patients previously hospitalized due to COVID-19 pneumonia who visited the radiology department of a tertiary care center for imaging follow-up were consecutively enrolled between March 2020 and July 2021. Exclusion criteria were acute respiratory distress syndrome, requirement of intubation and/or mechanical ventilation, pulmonary embolism, and any interstitial lung disease. High-resolution volumetric noncontrast chest CT scans were acquired at 3, 6, and 12 months from the first diagnosis and were compared with baseline CT scans. The imaging features analyzed were ground-glass opacity (GGO), consolidation, pleuroparenchymal band, linear atelectasis, bronchiectasis and/or bronchiolectasis, reticulation, traction bronchiectasis and/or bronchiolectasis, and honeycombing. The prevalence distribution of lung abnormalities was recorded at all time points. RESULTS: Eighty-four participants (56 men; mean age, 61 years ± 11 [SD]) were studied. GGOs and consolidations represented the main baseline lung abnormalities, accounting for a median severity score of 9 (IQR, 7-12.7; maximum possible score, 20), which indicates moderate lung involvement. The baseline prevalence of GGOs decreased from 100% to 2% of participants at 1 year, and that of consolidations decreased from 71% to 0% at 6 months. Fibrotic-like abnormalities (pleuroparenchymal bands, linear atelectasis, bronchiectasis and/or bronchiolectasis) were detected at 3 months (50% of participants), 6 months (42% of participants), and 1 year (5% of participants). Among these, pleuroparenchymal bands were the most represented finding. Fibrotic changes (reticulation and traction bronchiectasis and/or bronchiolectasis) were detected at 3-6 months (2%) and remained stable at 1 year, with no evidence of honeycombing. At 1 year, lung abnormalities due to COVID-19 pneumonia were completely resolved in 78 of 84 (93%) participants. CONCLUSION: Residual lung abnormalities in individuals hospitalized with moderate COVID-19 pneumonia were infrequent, with no evidence of fibrosis at 1-year chest CT. © RSNA, 2022.

[Bronchiectasis - a review].

Bronchiectasis is a disease that is characterized by permanent bronchial dilation. This can be localized or diffuse in the lungs. The disease can occur at any age and causes cough, sputum production and repeated infections. It is more common in women and incidence increases with age. Bronchiectasis is characterized by repeated episodes of worsening symptoms that are usually caused by respiratory infections. The cause of bronchiectasis can be unknown but it can be caused by respiratory diseases and diseases outside the chest. Examples of such diseases are asthma, chronic obstructive pulmonary disease, rheumatoid arthritis in addition to immune deficiency. Disease profile is therefore different for each patient. Bronchiectasis is diagnosed with computerized tomography of the chest in addition to clinical symptoms. Workup to diagnose other diseases that could be causing it is therefore important. For that detailed history, physical examination and additional investigations are appropriate. Patients with bronchiectasis have decreased health related quality of life and increased mortality. Treatment focuses on treatment of underlying diseases, airway clearance and treatment of infections. Pulmonary rehabilititation is also important. Regular follow-up is important. This is a review on bronchiectasis that is intended for a spectrum of physicians, because bronchiectasis can be seen in primary care, hospitals and out of hospital.

Assessment of early lung disease in young children with CF: A comparison between pressure-controlled and free-breathing chest computed tomography.

BACKGROUND: Chest computed tomography (CT) in children with cystic fibrosis (CF) is sensitive in detecting early airways disease. The pressure-controlled CT-protocol combines a total lung capacity scan (TLC PC-CT) with a near functional residual capacity scan (FRC PC-CT) under general anesthesia, while another CT-protocol is acquired during free breathing (FB-CT) near functional residual capacity. The aim of this study was to evaluate the sensitivity in detecting airways disease of both protocols in two cohorts. METHODS: Routine PC-CTs (Princess Margaret Children's Hospital) and FB-CTs (Erasmus MC-Sophia Children's Hospital) were retrospectively collected from CF children aged 2 to 6 years. Total airways disease (%disease), bronchiectasis (%Bx), and low attenuation regions (%LAR) were scored on CTs using the Perth-Rotterdam annotated grid morphometric analysis-CF method. The Wilcoxon signed-rank test was used for differences between TLC and FRC PC-CTs and the Wilcoxon rank-sum test for differences between FRC PC-CTs and FB-CTs. RESULTS: Fifty patients with PC-CTs (21 male, aged 2.5-5.5 years) and 42 patients with FB-CTs (26 male, aged 2.3-6.8 years) were included. %Disease was higher on TLC PC-CTs compared with FRC PC-CTs (median 4.51 vs 2.49; P < .001). %Disease and %Bx were not significantly different between TLC PC-CTs and FB-CTs (median 4.51% vs 3.75%; P = .143 and 0.52% vs 0.57%; P = .849). %Disease, %Bx, and %LAR were not significantly different between FRC PC-CTs and FB-CTs (median 2.49% vs 3.75%; P = .055, 0.54% vs 0.57%; P = .797, and 2.49% vs 1.53%; P = .448). CONCLUSIONS: Our data suggest that FRC PC-CTs are less sensitive than TLC PC-CTs and that FB-CTs have similar sensitivity to PC-CTs in detecting lung disease. FB-CTs seem to be a viable alternative for PC-CTs to track CF lung disease in young patients with CF.

Visual Assessment of Chest Computed Tomography Findings in Anti-cyclic Citrullinated Peptide Antibody Positive Rheumatoid Arthritis: Is it Associated with Airway Abnormalities?

INTRODUCTION: We aimed to evaluate the association between specific anti-cyclic citrullinated peptide antibody (ACCPA) and pulmonary abnormalities in rheumatoid arthritis (RA) subjects. METHODS: Computed tomography (CT) images of 83 subjects with RA were evaluated in a blind fashion. Enrolled subjects underwent autoantibody testing to determinate titer of ACCPA and rheumatoid factor, and pulmonary function testing. Visual CT assessment included lobar analysis for extent of semi-quantitative total interstitial lung disease score (ILDS) and each airway abnormality score (bronchiectasis, bronchial wall thickening, centrilobular nodules, and expiratory air trapping). Correlation tests, and simple and multiple regression analyses were performed to determine the relationship between the visual CT abnormalities, physiologic parameters, and autoantibody titers. RESULTS: ACCPA-positive subjects had a greater extent and higher prevalence of small airway abnormalities including centrilobular nodules and air trapping compared to ACCPA-negative subjects (all p < 0.05). Bronchiectasis and bronchial wall thickening correlated with the ratio of forced expiratory volume in 1 s and forced vital capacity (FVC) (r = -0.236 and r = -0.329, all p < 0.05), and ILDS correlated with FVC and the diffusing capacity of the lung for carbon monoxide (r = -0.218 and r = -0.366, all p < 0.05). Bronchial wall thickening and air trapping correlated with ACCPA titers (r = 0.235 and r = 0.264, all p < 0.05). Air trapping and bronchial wall thickening were significantly associated with ACCPA titers. CONCLUSION: In ACCPA (+) RA, visual CT assessment of large and small airways beyond RA-ILD, which is attributable to RA-related autoimmunity, can provide valuable information regarding airway abnormalities, regardless of the patients' physiologic airflow limitations.

Assessment of early bronchiectasis in young children with cystic fibrosis is dependent on lung volume.

OBJECTIVE: The aim of this study was to determine whether assessment of early CT scan-detected bronchiectasis in young children with cystic fibrosis (CF) depends on lung volume. METHODS: This study, approved by the hospital ethics committee, included 40 young children with CF from a newborn screened population contributing paired volume-controlled inspiratory and expiratory volumetric chest CT scans acquired under general anesthesia while clinically stable. Bronchiectasis was assessed with a semiquantitative CT scan score in inspiration and expiration, and the sensitivity of the expiratory CT scan to detect bronchiectasis was compared with the inspiratory CT scan by sensitivity and intraclass correlation coefficient analysis and Bland-Altman plots. Matched inspiratory and expiratory airway-vessel measurements were obtained in a subset of 10 children, and the relationship between lung volume and airway:vessel ratio after adjusting for age and vessel size was examined with the use of a linear regression model with generalized estimating equations. The number of visible airways in inspiration and expiration was compared in all 40 children by Wilcoxon signed rank test. RESULTS: Expiratory scans had poor sensitivity (0.46) to detect bronchiectasis, underestimating disease extent (P < .001). Airway:vessel ratios were consistently higher in inspiration, independent of age and vessel size (P < .001), with significantly more airways visible in inspiration than in expiration, independent of age (median, 71 vs 28, respectively; P < .001). CONCLUSIONS: In young children with CF, radiologic assessment of early bronchiectasis with chest CT scan depends on lung volume; thus, expiratory scans may not be appropriate for evaluating bronchiectasis in this population. Lung volume during CT image acquisition should be standardized to evaluate airway dimensions in young children.

Comparison between conventional interrupted high-resolution CT and volume multidetector CT acquisition in the assessment of bronchiectasis.

The aim of this study was to determine whether there is superior diagnostic accuracy for the detection and exclusion of bronchiectasis using 16-slice CT of the chest (1 mm) compared with conventional high-resolution CT (HRCT) of the chest (10 mm). A prospective study was carried out in patients who were referred for chest CT by a chest physician for the investigation of bronchiectasis over a 1-year period. All scans were performed using a 16-slice CT scanner. In addition to contiguous 1 mm slices, conventional HRCT images (1 mm slice every 10 mm) were prepared. Both datasets were dual read. There were 53 patients with a median age of 62 years (range, 51.5-71.5 years), comprising 14 males and 39 females. 10 of 53 scans had no bronchiectasis in either dataset. 36 patients had bronchiectasis diagnosed on both HRCT and 1 mm scans. Two patients had tubular bronchiectasis on the HRCT scans, which was not confirmed on the 1 mm scans. Five patients had confirmed tubular bronchiectasis on the 1 mm scans, which was not identified on HRCT scans. 40 extra lobes demonstrated bronchiectasis on the 1 mm vs the HRCT scans; of these, half were labelled as definite bronchiectasis on the 1 mm scan. There was a 32% increased confidence with the 1 mm scans compared with conventional HRCT of the chest in the diagnosis of bronchiectasis (p < 0.001). In conclusion, there is improved diagnostic accuracy and confidence for diagnosis and exclusion of bronchiectasis using 16-slice chest CT (1 mm cuts) compared with conventional HRCT of the chest.

Completion pneumonectomy for bronchiectasis: morbidity, mortality and management.

BACKGROUND: Completion pneumonectomy performed for benign causes is associated with a high morbidity and mortality. We analyzed the patients who underwent completion pneumonectomy procedure for bronchiectasis, which constitutes a specific benign condition, together with the indications for surgery, the difficulties encountered during operations and the postoperative results. METHODS: Records of all patients who underwent completion pneumonectomy for the diagnosis of brochiectasis between January 1991 and April 2006 at the thoracic surgery clinic of a training and research hospital specializing in chest diseases and chest surgery were retrospectively evaluated. The age and the gender of the patients, etiologic factors, symptoms, characteristics of the first operation, the time between the first operation and completion pneumonectomy, and postoperative follow-up are examined. RESULTS: During the evaluation period of more than 15 years, 23 patients underwent completion pneumonectomy. The median age of these 23 patients was 28 (range: 9 - 53); 17 of the patients were male and 6 were female. The most common indication for surgery was recurrent lung infections (n = 15). The most common symptoms were cough (n = 21), expectoration (n = 19), and hemoptysis (n = 15). The mean time between the first operation and the completion pneumonectomy was 4.9 years (range: 5 months - 11 years). Left completion pneumonectomy was performed in 14 and right completion pneumonectomy was performed in 9 cases. The mean duration of hospital stay was 16.7 days (range: 12 - 42 days). The course after surgery was uneventful in all patients. The mortality rate was 0 % and morbidity was 43.5 %. CONCLUSION: Although completion pneumonectomy for benign causes is a high risk procedure, it can be performed in selected patients with an acceptable morbidity and mortality after an effective preoperative medical therapy for inflammation of the lungs and with careful dissection at the operation.

Risk factors affecting outcome and morbidity in the surgical management of bronchiectasis.

OBJECTIVE: Bronchiectasis continues to be a major cause of morbidity and mortality in developing countries. The purpose of this study was to present the results of our 14 years of surgical experience to re-evaluate our indications for using surgical therapy and to analyze several factors that might affect the outcome and postoperative complications of this disease. METHOD: Age, sex, etiologic factors, symptoms, the duration of symptoms, radiologic and radionuclide examinations, preoperative evaluation, surgical procedures, postoperative morbidity and mortality, and the follow-up results from 143 patients operated on for bronchiectasis between January 1992 and January 2006, were reviewed retrospectively. RESULTS: One hundred forty-three patients underwent 148 operations for bronchiectasis. The mean age was 23.4 years. Complete resection was achieved in 118 patients. The morbidity rate was 23.0% and the mortality rate was 1.3%. Postoperatively, 75.9% of the patients were free of symptoms, 15.7% were improved, and 8.2% showed no improvement or were worse. The logistic regression analysis showed that a history of tuberculosis and incomplete resection were independent predictors of the operative result. Moreover, the lack of a preoperative bronchoscopic examination, a forced expiratory volume in 1 second of less than 60% of the predicted value, a history of tuberculosis, and incomplete resection were independent predictors of postoperative complications. CONCLUSIONS: A history of tuberculosis and incomplete resection were risk factors both for postoperative complications and for a worse operative result. The lack of a preoperative bronchoscopic examination and a low forced expiratory volume in 1 second were risk factors for postoperative complications. Surgery for multiple segments on different lobes should be performed whenever possible.

Three-dimensional quantitative assessment of lung parenchyma in cystic fibrosis: preliminary results.

PURPOSE: The aim of this study was to assess the feasibility of three-dimensional (3D) reconstructions and quantitative analysis of the volume of each component of the lung with cystic fibrosis (CF). MATERIALS AND METHODS: Twenty-two patients with CF (mean age 17+/-8 years) were included in the study. The patients underwent an unenhanced single-slice spiral computed tomography (CT) chest scan with the following parameters: collimation 3 mm, table feed 6 mm x rot(-1), reconstruction interval 1 mm, soft tissue reconstruction kernel. Four image data sets were obtained: native axial slices, cine-mode display, virtual bronchographic volume-rendered images with algorithm for tissue transition display and virtual endoluminal views. The lungs were segmented manually from the hilum to the visceral pleura on the axial images, and the entire lung volume was calculated. A histogram was generated representing the fractional volume of tissues, the density of which was within a preset range. A curve was then obtained from the histogram. RESULTS: Native axial images and cine-mode display allowed complete evaluation of lung volumes. Virtual bronchography allowed a better assessment of the distribution of bronchiectasis. Virtual bronchoscopy was limited by the fact that it visualised only the surface, without differentiating mucus from the bronchial wall. Manual segmentation and generation of density-volume curves required 41+/-7 min for each lung. Three curve patterns were identified depending on disease severity. CONCLUSIONS: Volume-density analysis of lungs with CF is feasible. Its main advantage is that image analysis is not analogical, as the assessment is not performed using scoring systems or similar ordinal scales. This technique cannot differentiate acute from chronic findings, and the predictive value of the curve should be assessed.

Multislice helical CT: the value of multiplanar image reconstruction in assessment of the bronchi and small airways disease.

We examined 23 consecutive patients (11 males and 12 females with mean age of 56 years) with possible airway diseases to assess the impact of multiplanar image reconstruction (MPR) on the degree of confidence and accuracy in diagnosing bronchial abnormalities and emphysema. The thorax was scanned contiguously at 1 mm slice thickness using Siemens Volume Zoom Multislice CT scanner. Images were reconstructed at 1 mm slice thickness (lung windows L-600HU W-1600HU utilizing high spatial frequency algorithm) in the axial (10 mm apart), sagittal (4 images per lung) and coronal (6 images) plane. Paddle wheel image reconstructions were also performed in the assessment of bronchiectasis. Axial images were assessed with and without the help of MPR by three chest radiologists at two separate occasions (at least 4 weeks apart). The presence of bronchiectasis, emphysema and bronchiolitis in each lobe was documented on a confidence scale of 0 to 3. The overall mean confidence for each observer with and without MPR was compared. Consensus diagnosis was used as the gold standard for the assessment of the diagnostic accuracy of each observer. A confidence score of 2 or more for any lobe was considered diagnostic of the particular airway disease. The diagnostic accuracy for each observer with and without MPR was compared. Consensus reporting diagnosed bronchiectasis in 7 patients (30.4%), bronchiolitis in 5 patients (21.7%) and emphysema in 12 patients (52%). MPR did not increase the confidence of assessing the different abnormalities for all observers but improvement in diagnosing bronchiectasis was noted in two observers. The improvement did not reach statistical significance. However, agreement between observers in the diagnosis of bronchiectasis and emphysema was improved when the MPR images were used in conjunction with standard axial imaging (Kappa statistic improved from 0.29 to 0.54 for bronchiectasis and from 0.7 to 0.81 for emphysema). Agreement on the diagnosis of bronchiolitis was not improved by MPR for all observers. Our results suggest that MPR seems to improve the confidence in diagnosing bronchiectasis and emphysema.

Thin-section spiral volumetric CT for the assessment of lobar and segmental bronchial stenoses.

Thin-section volumetric computed tomography (CT) was used to examine the lobar and segmental bronchi of five patients who had stenoses of these airways diagnosed by previous bronchography and/or bronchoscopy. Four of 23 lobar bronchi and 42 of 72 segmental bronchi were judged to be stenotic by CT. Our findings in this small group suggest that thin-section volumetric CT is a promising non-invasive technique that is likely to prove useful in the assessment of such stenoses in the future.

Bronchial dilatation in patients with HIV infection: CT assessment and correlation with pulmonary function tests and findings at bronchoalveolar lavage.

OBJECTIVE: Symptoms of airway disease occur in patients infected with HIV, and bronchiectasis has been reported in patients with AIDS. We evaluated thin-section thoracic CT scans in HIV-positive individuals for bronchial dilatation and correlated imaging findings with pulmonary function abnormalities and findings at bronchoalveolar lavage (BAL). SUBJECTS AND METHODS: Sixty-one subjects, 50 of whom were HIV-positive and 11 of whom were HIV-negative, underwent thin-section CT, BAL, and pulmonary function tests. Two radiologists evaluated the CT scans on two separate occasions for bronchial dilatation in each lobe. BAL and pulmonary function test data in the subjects with bronchial dilatation were compared with such data in subjects with normal bronchi seen on CT scans. RESULTS: Eighteen of the 50 HIV-positive subjects and none of the HIV-negative subjects had bronchial dilatation revealed by CT. Subjects with bronchial dilatation revealed by CT had significantly higher BAL neutrophil counts (p = .014) and significantly lower diffusing capacity (p = .003) than did subjects with normal bronchi revealed by CT. CONCLUSION: Bronchial dilatation is commonly revealed by CT scans of HIV-positive individuals. The association of elevated levels of BAL neutrophils and decreased diffusing capacity with bronchial dilatation that we found in this study suggests that the neutrophil may be associated with airway damage and lung destruction in patients who are infected with HIV.

Value of routine pre-operative chest X-ray in patients over the age of 40 years.

The overall usefulness of routine chest X-ray, its cost benefit ratio and effect on anaesthetic management in patients over the age of 40 years was assessed. Four hundred and seventy-seven consecutive patients undergoing elective non-cardiopulmonary surgery with no cardiopulmonary diseases, having a routine preoperative chest x-ray were selected at the Aga Khan University Hospital, Karachi. Twenty five (5.2%) were excluded from the study as their chest x-ray were not available at the time of surgery. Twenty eight (8.3%) below and 33 (28.7%) above 60 years of age had abnormalities in chest x-ray but the difference in cardiac abnormalities in two age groups was insignificant. The frequency of lung field abnormalities increased with age from 3.2% in less than 60 to 15.6% in patients above 60 years of age. The difference in frequency of occurrence of lung field abnormalities was statistically significant in case of lung abnormalities. Only one case required change in anaesthetic management based on routine preoperative chest x-ray. Our study showed that the incidence of significant lung field abnormalities increased in patients aged 60 years and above with no history of chronic obstructive airway disease. We recommend routine preoperative chest x-ray be carried out only in patients over the age of 60 years.

Bronchiectasis: comparative assessment with thin-section CT and helical CT.

PURPOSE: To compare thin-section computed tomography (CT) and helical CT in the detection and assessment of the extent of bronchiectasis. MATERIALS AND METHODS: Both thin-section and helical CT scans were obtained in 50 consecutive patients with clinical symptoms suggestive of bronchiectasis. Thin-section CT was performed with 1.5-mm collimation and 10-mm intervals, and helical CT was performed with 3-mm collimation and a pitch of 1.6 during a 24-second breath hold. Three observers evaluated 593 segments on CT scans both independently and in consensus. Radiation dose was measured for both techniques. RESULTS: Bronchiectasis was noted in 77 segments (22 patients) on thin-section CT scans compared with 90 segments (26 patients) on helical CT scans. No findings were positive for bronchiectasis on only thin-section CT scans. Interobserver agreement was statistically significantly better (P < .05) in identification of segments that were positive for bronchiectasis on helical CT scans (kappa = 0.87) than on thin-section CT scans (kappa = 0.71). Total skin dose of radiation delivered with helical CT was 3.4 times greater than that delivered with thin-section CT. CONCLUSION: Helical scanning can improve CT depiction of bronchiectasis but with an increase in radiation exposure to the patient. It should be used in patients considered for surgery or for thin-section CT scans that are difficult to interpret.

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.

Bronchiectasis in children: assessment by CT.

The prevalence of bronchiectasis (BR), in general, is decreasing, yet the disease can produce significant morbidity in children. In the pediatric age group the classical investigation by bronchography implies general anaesthesia, thus carrying an additional risk of complications. CT has proved highly accurate in the diagnosis of BR in adults. It is also considered a reliable modality for the diagnosis of BR in children. This conclusion was reached by analysing the radiographic and the CT findings in 40 children with the clinical suspicion of BR in 25 of whom the CT examination was positive. Nine patients of this last group had bronchography as well. There was complete correlation in the diagnosis and location between the CT and the bronchographic findings. Thus, it seems that the occurrence of this disease is still high in the pediatric population in the appropriate clinical and radiological setting. The imaging evaluation of BR should include chest radiographs, computerized tomography and, if surgery is planned, bronchography as well.

High-resolution CT in the assessment of bronchiectasis in children.

To assess the possibilities and limitations of high-resolution CT (HRCT) in the evaluation of bronchiectasis in children, we conducted a prospective study of 20 children with clinical and/or chest film findings suggestive of this diagnosis. The 2-mm collimation, 4.3-s HRCT scans with 10 mm interslice spacing were obtained in areas of suspected bronchiectasis; in nonsuspect areas 25-30 mm interslice spacing was used. No preparation for examination was required. Bronchiectasis was revealed in ten patients (50%), being bilateral in four cases and unilateral in six cases. All types of bronchiectatic patterns were found. Cooperation during the examination was the only difference when compared with an investigation of adults. It was not a serious problem in children aged 7 years and older; scans in 6-year-old children were diagnostic but not ideal. Nondiagnostic scans were obtained in a 3-year-old girl. At the time of the scans only one patient had undergone surgery. Preoperative bronchography confirmed the CT findings. The authors conclude that HRCT can limit the need for bronchography in children with a CT finding of focal bronchiectasis in whom surgery is contemplated. When using longer scanning times it is not possible to obtain good results without sedation of children younger than 6 years.

High resolution CT and bronchography in the assessment of bronchiectasis.

To elucidate the reliability of CT in the assessment of bronchiectasis, a retrospective study of high resolution CT and bronchography was carried out. A segment by segment comparison of 259 segmental bronchi from 70 lobes of 27 lungs in 19 patients was performed using bronchography as standard. CT was positive in 87 of 89 segmental bronchi with bronchiectasis giving a false-negative rate of 2%. CT was negative in 169 of 170 segmental bronchi without bronchiectasis at bronchography, giving a false-positive rate of 1%. There was agreement between the two modalities in identifying the different types of bronchiectasis.