Quantitative Computed Tomography Analysis of the Longitudinal Change Between Centrilobular and Paraseptal Emphysema Subtypes: A Retrospective Study

OBJECTIVE

This study aimed to investigate the difference between the extent of centrilobular emphysema (CLE) and paraseptal emphysema (PSE) on follow-up chest CT scans and their relationship to the cross-sectional area (CSA) of small pulmonary vessels.

METHODS

Sixty-two patients (36 CLE and 26 PSE) who underwent 2 chest CT scans were enrolled in this study. The percentage of low attenuation volume (%LAV) and total CSA of the small pulmonary vessels <5 mm 2 (%CSA < 5) were measured at the 2 time points. Analysis of the initial %CSA < 5 and the change in the %LAV and %CSA < 5 on follow-up imaging was performed.

RESULTS

The initial %CSA < 5 was not significantly different between the CLE and the PSE groups (CLE, 0.66 vs. PSE, 0.71; P = 0.78). There was no significant difference in the longitudinal change in the %LAV between the 2 groups (CLE, -0.048% vs. PSE, 0.005%; P = 0.26). The longitudinal change in the %CSA < 5 in patients with PSE significantly decreased compared with those with CLE (CLE, 0.025% vs. PSE, -0.018%; P = 0.02).

CONCLUSIONS

The longitudinal change in the %CSA < 5 was significantly different for patients with CLE and PSE, demonstrating an important pathophysiological difference between the subtypes.

A Long-term Persistent Vascular Fluorodeoxyglucose Uptake in a Patient with Large-vessel Vasculitis

We herein report a case of large-vessel vasculitis in a 57-year-old woman who developed an intermittent fever and weight loss. While contrast-enhanced computed tomography was noncontributory, positron emission tomography-computed tomography (PET-CT) revealed the diffuse, intense uptake of fluorodeoxyglucose (FDG) in the aorta and its branches. Although she had no signs of relapse after successful oral corticosteroid therapy, PET-CT at 30 months revealed a persistent FDG uptake in the large vessels, which warranted regular follow-up imaging for vascular complications. In cases with an intense FDG uptake at the diagnosis, PET-CT follow-up after clinical remission may help predict the risk of relapse and vascular complications.

Endovascular retrieval of a Gunther-tulip vena cava filter migrated into the right atrium

A 72-year-old male underwent placement of a Gunther-tulip vena cava filter to prevent development of a pulmonary embolism. One month later, when we tried to retrieve the Gunther-tulip vena cava filter via a transjugular approach, the filter detached from the snare and became free in the outer sheath. The Gunther-tulip vena cava filter did not reopen in the inferior vena cava probably because it became entangled with a thrombus; rather, the filter migrated into the right atrium. The filter orientation rendered the transjugular approach inappropriate; we used a bilateral transfemoral approach to aid filter retrieval. It is necessary to be very cautious when reopening a filter that has closed within the sheath. Although the filter migrated into the heart, we retrieved it using a combined approach.

Percutaneous transgastric pancreatic duct drainage for pancreaticojejunal leak after pancreaticoduodenectomy

Pancreaticojejunal anastomotic leakage is one of the severe complications after pancreaticoduodenectomy and is often difficult to manage. A 64-year-old man status post pancreaticoduodenectomy had the gastroduodenal artery stump bleeding caused by the pancreaticojejunal anastomotic leakage, successfully treated by placing a covered stent. To control the leakage, subsequent percutaneous transgastric pancreatic duct puncture was performed under fluoroscopic guidance, targeting a surgically placed pancreaticojejunal internal drainage catheter. A 5 F catheter with side holes was inserted into the main pancreatic duct, the tip of which was placed in the anastomosed jejunum. The leak was successfully treated using this catheter. Percutaneous transgastric pancreatic duct drainage might be a useful and feasible option to resolve the condition.

The Association Between Bronchial Wall CT Attenuation and Spirometry in Patients with Bronchial Asthma

RATIONALE AND OBJECTIVE

The purpose of this study was to evaluate the correlation between generation-based bronchial wall attenuation on thin-section computed tomography (CT) scans and airflow limitation in patients with bronchial asthma.

MATERIALS AND METHODS

This study included 28 bronchial asthma patients (13 men, 15 women; age range, 23-89 years) who underwent both chest CT and spirometry. On CT, the mean values of peak wall attenuation, wall area percentage, and luminal area were measured in the segmental, subsegmental, and sub-subsegmental bronchi of the right B1 and B10 bronchi. Correlations of the CT measurements with forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC), percent predicted forced expiratory flow at 25%-75% of the FVC (%pred forced expiratory flow25-75), and percent predicted peak flow rate were evaluated with Spearman's rank correlation test.

RESULTS

The peak wall attenuation of each generation of segmental bronchi significantly correlated with the forced expiratory volume in 1 second/FVC (B1 segmental, ρ = -0.683, p < 0.0001; B1 subsegmental, ρ = -0.875, p < 0.0001; B1 sub-subsegmental, ρ = -0.926, p < 0.0001; B10 segmental, ρ = -0.811, p < 0.0001; B10 subsegmental, ρ = -0.903, p < 0.0001; B10 sub-subsegmental ρ = -0.950, p < 0.0001). Similar correlations were found between the peak wall attenuation and %pred forced expiratory flow 25-75 or percent predicted peak flow rate. Overall, the correlation coefficients were relatively high in the more peripheral bronchial generations. In all measurements, the coefficients of the peak wall attenuations were higher than those of the wall area percentage and luminal area.

CONCLUSION

Peak attenuation of the bronchial wall, particularly in the peripheral bronchi, measured on CT is a good biomarker for the severity of bronchial asthma.

Relationship between current smoking, visual CT findings and emphysema index in cigarette smokers

PURPOSE

To evaluate whether visual CT findings could account for the effect of current smoking.

METHODS

500 CT scans were visually evaluated within each lobe. A multivariate model for emphysema index was constructed containing previously described confounders in addition to the visual components associated with smoking status.

RESULTS

Current smokers displayed 23% less visual emphysema, 19% more airway wall thickening, and 188% more centrilogular nodule than former smokers (all p < 0.001). The effect of current smoking on the emphysema index decreased after adjustment with confounders and visual parameters.

CONCLUSIONS

Visual CT findings could partially account for the effect of current smoking.

Quantitative CT Evaluation of Small Pulmonary Vessels in Patients with Acute Pulmonary Embolism

RATIONALE AND OBJECTIVES

The objective of this study was to investigate the correlation between the computed tomography (CT) cross-sectional area (CSA) of small pulmonary vessels and the CT obstruction index in patients with acute pulmonary embolism (PE) and the correlation between the changes in these measurements after anticoagulant therapy.

MATERIALS AND METHODS

Fifty-two patients with acute PE were selected for this study. We measured the CSA less than 5 mm² on coronal reconstructed images to obtain the percentage of the CSA (%CSA < 5). CT angiographic index was obtained based on the Qanadli method for the evaluation of the degree of pulmonary arterial obstruction. Spearman rank correlation analysis was used to evaluate the relationship between the initial and the follow-up values and changes in the %CSA < 5 and the CT obstruction index.

RESULTS

There was no significant correlation between the %CSA < 5 and CT obstruction index on both initial (ρ = -0.03, P = 0.84) and follow-up (ρ = -0.03, P = 0.82) assessments. In contrast, there was a significant negative correlation between the changes in %CSA < 5 and the CT obstruction index (ρ = -0.59, P < 0.0001).

CONCLUSIONS

Although the absolute %CSA < 5 and CT obstruction index were not significantly correlated, the changes in the values of the two parameters had a significant correlation. Changes in %CSA < 5, which can be obtained easily, can be used as biomarker of therapeutic response in patients with acute PE.

Selective venous sampling supports localization of adenoma in primary hyperparathyroidism

Background

Selective venous sampling (SVS) is an invasive localization study for persistent or recurrent hyperparathyroidism.

Purpose

To assess the role of SVS in addition to non-invasive imaging for primary hyperparathyroidism (pHPT).

Material and Methods

This study was approved by the institutional review board and included 14 patients who underwent SVS and subsequent parathyroidectomy between January 2014 and April 2017 following a clinical diagnosis of pHPT. All patients underwent pre-SVS non-invasive imaging, including ultrasound, computed tomography (CT), and ^99mTc-MIBI scintigraphy, and sensitivity was assessed using the operative and pathological findings.

Results

In all but one case, a single parathyroid adenoma was responsible for the pHPT; the remaining case exhibited a chemical response following surgical removal of parathyroid tissue. The sensitivity (%) for ultrasound, CT, ^99mTc-MIBI scintigraphy, and SVS was 76.9, 84.6, 69.2, and 76.9, respectively. SVS yielded positive results in four patients with discordant results and one patient with non-detectable results on imaging. In seven patients, a significant increase in the intact parathyroid hormone level was recognized only in the thyroid veins. The procedure time was in the range of 52–183 min (median = 89.5 min).

Conclusion

The addition of SVS to a non-invasive imaging study would be helpful to locate the responsible lesion of pHPT with discordant or non-detectable results on imaging for initial surgical treatment as well.

Early and Mid-Term Results of Endovascular Aortic Repair Using a Crossed-Limb Technique for Patients with Severely Splayed Iliac Angulation

Objective: We evaluated early and mid-term results of endovascular aortic repair (EVAR) using crossed-limb and non-crossed-limb techniques.

Material and Methods: From December 2011 to October 2013, 37 patients (31 men; mean age 75.4 years) were treated with EVAR (crossed-limb, 21 and non-crossed-limb, 16). We compared technical success, maximum short-axis diameter of abdominal aortic aneurysm, iliac angulation, time for catheterization of the short contralateral limb gate of the main body (SCT), and complications between the groups.

Results: The mean follow-up period was 810±230 days. The technical success rate was 100%. There was no significant difference between the groups in terms of mean short-axis diameter. Iliac angulation was significantly wider in the crossed-limb group (53.3±14.6 vs. 39.4±13.0, p=0.0049). There was no significant difference between the groups in terms of SCT. Limb occlusion occurred in two cases (one crossed-limb and one non-crossed-limb). There were no aneurysm-related deaths.

Conclusion: There were no differences between the crossed-limb and non-crossed-limb techniques in terms of early and mid-term results of EVAR. A crossed-limb technique can be performed safely without prolonged SCT even in severely splayed iliac angulation cases.

Idiopathic Pulmonary Fibrosis: Data-driven Textural Analysis of Extent of Fibrosis at Baseline and 15-Month Follow-up

Purpose To evaluate associations between pulmonary function and both quantitative analysis and visual assessment of thin-section computed tomography (CT) images at baseline and at 15-month follow-up in subjects with idiopathic pulmonary fibrosis (IPF). Materials and Methods This retrospective analysis of preexisting anonymized data, collected prospectively between 2007 and 2013 in a HIPAA-compliant study, was exempt from additional institutional review board approval. The extent of lung fibrosis at baseline inspiratory chest CT in 280 subjects enrolled in the IPF Network was evaluated. Visual analysis was performed by using a semiquantitative scoring system. Computer-based quantitative analysis included CT histogram-based measurements and a data-driven textural analysis (DTA). Follow-up CT images in 72 of these subjects were also analyzed. Univariate comparisons were performed by using Spearman rank correlation. Multivariate and longitudinal analyses were performed by using a linear mixed model approach, in which models were compared by using asymptotic χ² tests. Results At baseline, all CT-derived measures showed moderate significant correlation (P < .001) with pulmonary function. At follow-up CT, changes in DTA scores showed significant correlation with changes in both forced vital capacity percentage predicted (ρ = -0.41, P < .001) and diffusing capacity for carbon monoxide percentage predicted (ρ = -0.40, P < .001). Asymptotic χ² tests showed that inclusion of DTA score significantly improved fit of both baseline and longitudinal linear mixed models in the prediction of pulmonary function (P < .001 for both). Conclusion When compared with semiquantitative visual assessment and CT histogram-based measurements, DTA score provides additional information that can be used to predict diminished function. Automatic quantification of lung fibrosis at CT yields an index of severity that correlates with visual assessment and functional change in subjects with IPF. ^© RSNA, 2017.

Decrease in Small Pulmonary Vessels on Chest Computed Tomography in Light Smokers Without COPD: An Early Change, but Correlated with Smoking Index

PURPOSE

The aim of this study was to evaluate the relationship between the amount of smoking and the cross-sectional area (CSA) of small pulmonary vessels in light smokers without a diagnosis of chronic obstructive pulmonary disease (COPD).

METHODS

This retrospective study was approved by our institutional review board, which waived the need for informed consent from patients. The study included 34 current smokers without COPD, who were defined as light smokers based on their smoking history (≤25 pack years). The CSA of small pulmonary vessels (<5 mm² [CSA_<5]) was measured on computed tomography (CT) scans, and the percentage of total CSA of the lung (%CSA_<5) was calculated. The extent of emphysema was also assessed as the percentage of low attenuation area (%LAA, <-950 Hounsfield units). The correlations of %CSA_<5 and %LAA with pack years were determined using the Spearman rank correlation.

RESULTS

There was a significant negative correlation between %CSA_<5 and pack years, whereas no significant correlation was found between %LAA and pack years. The correlations between pack years and percent predicted forced expiratory volume in 1 s (FEV₁) and FEV₁/forced vital capacity were not significant.

CONCLUSIONS

The percentage of total CSA of the lung made up of small pulmonary vessels in light smokers without COPD significantly decreases with increasing amount of smoking, in contrast to emphysema measurements. This suggests that small pulmonary vessels might have been injured or might have degenerated because of smoking, and might represent an initial stage in the development of COPD.

Percutaneous Direct Embolization for Pseudoaneurysm at the Gallbladder Fossa after Cholecystectomy

Postoperative pseudoaneurysm at the gallbladder fossa is a rare complication of cholecystectomy. The typical clinical presentations of this condition are intraparenchymal or intraperitoneal hemorrhage or rupture into the gastrointestinal tract, and this may be life-threatening. For the treatment of pseudoaneurysms, percutaneous transarterial embolization is considered first-line. We present a case of pseudoaneurysm at the gallbladder following cholecystectomy, which was successfully treated with echo-guided percutaneous transhepatic direct embolization using N-butyl cyanoacrylate, after the failure of transarterial embolization.

Texture-based Quantification of Centrilobular Emphysema and Centrilobular Nodularity in Longitudinal CT Scans of Current and Former Smokers

RATIONALE AND OBJECTIVES

The effect of smoking cessation on centrilobular emphysema (CLE) and centrilobular nodularity (CN), two manifestations of smoking-related lung injury on computed tomography (CT) images, has not been clarified. The objective of this study is to leverage texture analysis to investigate differences in extent of CLE and CN between current and former smokers.

MATERIALS AND METHODS

Chest CT scans from 350 current smokers, 401 former smokers, and 25 control subjects were obtained from the multicenter COPDGene Study, a Health Insurance Portability and Accountability Act-compliant study approved by the institutional review board of each participating clinical study center. Additionally, for 215 of these subjects, a follow-up CT scan was obtained approximately 5 years later. For each CT scan, 5000 circular regions of interest (ROIs) of 35-pixel diameter were randomly selected throughout the lungs. The patterns present in each ROI were summarized by 50 computer-extracted texture features. A logistic regression classifier was leveraged to classify each ROI as normal lung, CLE, or CN, and differences in the percentages of normal lung, CLE, and CN by study group were assessed.

RESULTS

Former smokers had significantly more CLE (P <0.01) but less CN (P <0.001) than did current smokers, even after adjustment for important covariates such as patient age, GOLD stage, smoking history, forced expiratory volume in 1 second, gas trapping, and scanner model. Among patients with longitudinal CT scans, continued smoking led to a slight increase in CLE (P = 0.13), whereas sustained abstinence from smoking led to further reduction in CN (P <0.05).

CONCLUSIONS

The proposed texture-based approach quantifies the extent of CN and CLE with high precision. Differences in smoking-related lung disease between longitudinal scans of current smokers and longitudinal scans of former smokers suggest that CN may be reversible on smoking cessation.

Radiologic–pathologic discordance in biopsy-proven usual interstitial pneumonia

The aim of this study was to compare the clinical, radiological and histological findings in a large population of subjects enrolled during a multicentre study of idiopathic pulmonary fibrosis, with a focus on discordance between imaging and histologic diagnoses of usual interstitial pneumonia (UIP).

Two independent radiologists retrospectively reviewed 241 subjects who underwent high-resolution computed tomography (HRCT) and surgical lung biopsies. HRCT findings were classified as UIP, possible UIP and inconsistent with UIP. Histological findings were classified as definite, probable, possible and not UIP.

Of the 241 cases, 102 (42.3%) had HRCT findings of UIP, 64 (26.6%) had possible UIP and 75 (31.1%) were inconsistent with UIP. Among those with UIP on HRCT, 99 (97.1%) had histologically definite or probable UIP (concordant group), and 71 (94.7%) of those with “inconsistent” HRCT features had histologically definite or probable UIP (discordant group). Discordant subjects were slightly younger and less likely to be smokers than concordant subjects, but no survival differences were identified.

In this population of patients enrolled with a diagnosis of idiopathic pulmonary fibrosis, 94.7% of those with HRCT findings “inconsistent with UIP” demonstrated histological UIP. This suggests that the term “inconsistent with UIP” is misleading.

Clinical and Radiologic Disease in Smokers With Normal Spirometry

IMPORTANCE

Airflow obstruction on spirometry is universally used to define chronic obstructive pulmonary disease (COPD), and current or former smokers without airflow obstruction may assume that they are disease free.

OBJECTIVE

To identify clinical and radiologic evidence of smoking-related disease in a cohort of current and former smokers who did not meet spirometric criteria for COPD, for whom we adopted the discarded label of Global Initiative for Obstructive Lung Disease (GOLD) 0.

DESIGN, SETTING, AND PARTICIPANTS

Individuals from the Genetic Epidemiology of COPD (COPDGene) cross-sectional observational study completed spirometry, chest computed tomography (CT) scans, a 6-minute walk, and questionnaires. Participants were recruited from local communities at 21 sites across the United States. The GOLD 0 group (n = 4388) (ratio of forced expiratory volume in the first second of expiration [FEV1] to forced vital capacity >0.7 and FEV1 ≥80% predicted) from the COPDGene study was compared with a GOLD 1 group (n = 794), COPD groups (n = 3690), and a group of never smokers (n = 108). Recruitment began in January 2008 and ended in July 2011.

MAIN OUTCOMES AND MEASURES

Physical function impairments, respiratory symptoms, CT abnormalities, use of respiratory medications, and reduced respiratory-specific quality of life.

RESULTS

One or more respiratory-related impairments were found in 54.1% (2375 of 4388) of the GOLD 0 group. The GOLD 0 group had worse quality of life (mean [SD] St George's Respiratory Questionnaire total score, 17.0 [18.0] vs 3.8 [6.8] for the never smokers; P < .001) and a lower 6-minute walk distance, and 42.3% (127 of 300) of the GOLD 0 group had CT evidence of emphysema or airway thickening. The FEV1 percent predicted distribution and mean for the GOLD 0 group were lower but still within the normal range for the population. Current smoking was associated with more respiratory symptoms, but former smokers had greater emphysema and gas trapping. Advancing age was associated with smoking cessation and with more CT findings of disease. Individuals with respiratory impairments were more likely to use respiratory medications, and the use of these medications was associated with worse disease.

CONCLUSIONS AND RELEVANCE

Lung disease and impairments were common in smokers without spirometric COPD. Based on these results, we project that there are 35 million current and former smokers older than 55 years in the United States who may have unrecognized disease or impairment. The effect of chronic smoking on the lungs and the individual is substantially underestimated when using spirometry alone.

Life-Saving Embolization in a Patient with Recurrent Shock Due to a Type II Endoleak after Endovascular Aortic Repair for a Ruptured Abdominal Aortic Aneurysm

A man in his 80s underwent urgent endovascular aortic repair (EVAR) for a ruptured abdominal aortic aneurysm (RAAA). Surgery was completed without apparent complications, and the patient was returned to the Cardiac Care Unit. Two hours later, he again developed shock, and contrast-enhanced Computed Tomography showed extravasation from a type II endoleak (T2EL) involving the IMA. Transcatheter arterial embolization (TAE) was immediately performed, and the patient's vital signs stabilized soon after embolization. Abdominal compartment syndrome was suspected during the procedure, so a retroperitoneal hematoma evacuation was performed. The patient's postoperative course was satisfactory, and he transferred to another hospital. EVAR for RAAA would be useful, but it is necessary to be considered that T2EL can cause the aggravation of unstable circulation.

Quantitative CT evaluation in patients with combined pulmonary fibrosis and emphysema: correlation with pulmonary function

RATIONALE AND OBJECTIVES

The purpose of this study was to evaluate the correlations between objective quantitative computed tomography (CT) measurements of the extent of emphysematous and fibrotic lesions and the results of pulmonary function tests (PFTs) in patients with combined pulmonary fibrosis and emphysema (CPFE).

MATERIALS AND METHODS

This study involved 43 CPFE patients who underwent CT and PFTs. The extent of emphysematous lesions was obtained by calculating the percentage of low attenuation area (%LAA) values lower than -950 Hounsfield units (HU). Fibrotic lesions were defined as high attenuation area (HAA) using thresholds with pixels between 0 and -700 HU, and the extent of fibrosis was obtained by calculating the percentage of HAA (%HAA). The correlations of %LAA and %HAA with PFTs were evaluated by the Spearman rank correlation coefficients and multiple linear regression analysis.

RESULTS

A significant negative correlation was found between %HAA and diffusing capacity of the lung for carbon monoxide (DLco) %predicted (ρ = -0.747; P < .001), whereas no significant correlation was found between %LAA and DLco %predicted. On multiple linear regression analysis, although the %HAA and %LAA were independent contributors to DLco %predicted, the predictive power of %HAA was superior to that of %LAA.

CONCLUSIONS

In CPFE, the extent of fibrosis has a more significant impact on DLco than emphysema.

The clinical course of diffuse idiopathic pulmonary neuroendocrine cell hyperplasia

BACKGROUND

Current understanding of the clinical course of diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is poor and based predominantly on small case series. In our clinical experience, we have found that the diagnosis of DIPNECH is frequently delayed because respiratory symptoms are ascribed to other lung conditions. The objectives of this study were to collect and analyze longitudinal clinical data on pulmonary physiology, chest high-resolution CT (HRCT) imaging, and therapies to better delineate the course of disease.

METHODS

We established a cohort of patients (N = 30) with DIPNECH seen at our institution. We used descriptive statistics to summarize cohort characteristics and longitudinal analytic techniques to model FEV1 % predicted (FEV1%) over time.

RESULTS

All subjects were women who presented with long-standing cough and dyspnea. The majority had an FEV1% < 50% at the time of diagnosis. Forty percent were given a diagnosis of asthma as the cause for physiologic obstruction. The mean FEV1% for the entire cohort showed no statistically significant decline over time, but 26% of the subjects experienced a 10% decline in FEV1 within 2 years. Among the pathology samples available for review, 28% (five of 18) had typical carcinoids and 44% had associated constrictive bronchiolitis. We propose clinical diagnostic criteria for DIPNECH that incorporate demographic, pulmonary physiology, HRCT imaging, and transbronchial and surgical lung biopsy data.

CONCLUSIONS

DIPNECH is a female-predominant lung disease manifested by dyspnea and cough, physiologic obstruction, and nodules on HRCT imaging. Additional research is needed to understand the natural history of this disease and validate the proposed diagnostic criteria.

Physical functional capacity in idiopathic pulmonary fibrosis: performance characteristics of the continuous-scale physical function performance test

BACKGROUND

Physical functional capacity is impaired in idiopathic pulmonary fibrosis (IPF). There is no tool to measure this key clinical outcome. The continuous-scale physical function performance (CS-PFP) test is one that assesses activities of daily living, but it has never been used in IPF.

METHODS

We determined internal consistency of the CS-PFP. We used correlations to assess the strength of association between CS-PFP scores and various parameters of IPF severity, and compared the CS-PFP scores between patients with IPF and published values from a healthy control group.

RESULTS

Sixteen subjects completed the test and retest. Test-retest reliability (0.84, p = 0.003) and internal consistency (Cronbach's α = 0.91) were excellent. Subjects with IPF had significantly worse CS-PFP scores than controls (46.0 ± 11.1 vs 58.7 ± 12.5, p = 0.001). In IPF, the CS-PFP scores correlated moderately to very strongly with several disease severity variables.

CONCLUSION

The CS-PFP is a reliable and valid tool in IPF.

Quantitative CT measurements of small pulmonary vessels in chronic obstructive pulmonary disease: do they change on follow-up scans?

The aims of this study were to perform a longitudinal evaluation of the cross-sectional area (CSA) of small pulmonary vessels and the extent of emphysema measured on computed tomography (CT) scans of patients with chronic obstructive pulmonary disease (COPD), and to correlate the pulmonary vascular measurements with extent of emphysema. The institutional review board approved this retrospective study and waived the need for patients' informed consent. Seventy-four patients with COPD who underwent both initial and follow-up CT scans at an interval of ≥12 months were analysed. The CSA of small pulmonary vessels <5 mm(2) was measured, and the percentage of total CSA of the area of the lung (%CSA<5 ) was calculated. The extent of emphysema was assessed as the percentage of low attenuation area (%LAA, <-950 Hounsfield units). Comparisons between initial and follow-up measurements were performed using the Wilcoxon signed-rank test. The relationship between longitudinal changes in %CSA<5 and %LAA during the follow-up period was assessed using the Spearman rank correlation. The %LAA increased significantly on follow-up CT scans (P<0·0001). The %CSA<5 was slightly decreased on follow-up scans, but the difference was not significant. Although longitudinal change in %LAA was positively correlated with duration of follow-up period (ρ = 0·505, P<0·0001), longitudinal change in %CSA<5 was not. In conclusion, there was a progressive increase in the extent of emphysema over time, but no significant decrease in the CSA of small pulmonary vessels over the same time period.

Usefulness of coronal reconstruction CT images for quantitative evaluation of the cross-sectional area of small pulmonary vessels

RATIONALE AND OBJECTIVES

Cross-sectional area <5 mm(2) (CSA<5) is a computed tomography (CT) metric that has been used for the evaluation of pulmonary vessel alterations and perfusion. CSA<5 is calculated from three axial slices; thus, whether CSA<5 represents the small pulmonary vessel alterations in the whole lung remains unclear. The purpose of this study was to compare the measurements of CSA<5 using three axial slices and coronal reconstructed slices in the relationship between the measured CSA<5 and pulmonary perfusion measured using lung perfusion scintigraphy.

MATERIALS AND METHODS

This study comprised 28 subjects who underwent both noncontrast CT and lung perfusion scintigraphy. The present study measured CSA<5 using both three axial CT images and coronal reconstruction images and then obtained the percentage of the CSA in right lung to that in whole lung (R/W-CSA<5). Using anteroposterior and posteroanterior projections on technetium-99m macroaggregated albumin (MAA) lung perfusion scintigraphy, we obtained right and total lung counts and calculated the percentage of the right to whole lung counts (R/W-MAA). The correlations of the R/W-CSA<5 calculated using three axial slices (R/W-CSA(A)x<5) and coronal reconstructed slices (R/W-CSA(COR)<5) with R/W-MAA were evaluated using Spearman rank correlation analysis.

RESULTS

Both R/W-CSA(Ax)<5 and R/W-CSA(COR)<5 were significantly correlated with R/W-MAA; however, the correlation coefficient with R/W-CSA(COR)<5 (ρ = 0.842, P < .0001) was greater than that with R/W-CSA(Ax)<5 (ρ = 0.631, P = .0004).

CONCLUSIONS

Coronal reconstruction images appear suitable for quantitative measurement of CSA of small pulmonary vessels.

Pulmonary arterial enlargement in patients with acute exacerbation of interstitial pneumonia

The purpose of this study was to evaluate change in the size of the main pulmonary (PA) artery in patients with acute exacerbation of interstitial pneumonia (IP). Twenty-nine patients underwent computed tomography at baseline and at the time of acute IP exacerbation for the measurement of the diameters of the main PA and the ascending aorta. We found that the diameter of the main PA was significantly larger at the time of acute IP exacerbation than at baseline, which might reflect the alterations in pulmonary circulation.

Visual Assessment of CT Findings in Smokers With Nonobstructed Spirometric Abnormalities in The COPDGene® Study

Within the COPD Genetic Epidemiology (COPDGene^®) study population of cigarette smokers, 9% were found to be unclassifiable by the Global Initiative for chronic Obstructive Lung Disease (GOLD) criteria. This study was to identify the differences in computed tomography (CT) findings between this nonobstructed (GOLDU) group and a control group of smokers with normal lung function. This research was approved by the institutional review board of each institution. CT images of 400 participants in the COPDGene^® study (200 GOLDU, 200 smokers with normal lung function) were retrospectively evaluated in a blinded fashion. Visual CT assessment included lobar analysis of emphysema (type, extent), presence of paraseptal emphysema, airway wall thickening, expiratory air trapping, centrilobular nodules, atelectasis, non-fibrotic and fibrotic interstitial lung disease (ILD), pleural thickening, diaphragmatic eventration, vertebral body changes and internal thoracic diameters (in mm). Univariate comparisons of groups for each CT parameter and multiple logistic regression were performed to determine the imaging features associated with GOLDU. When compared with the control group, GOLDU participants had a significantly higher prevalence of unilateral diaphragm eventration (30% vs. 16%), airway wall thickening, centrilobular nodules, reticular abnormality, paraseptal emphysema (33% vs. 17%), linear atelectasis (60% vs. 35.6%), kyphosis (12% vs. 4%), and a smaller internal transverse thoracic diameter (255 ± 22.5 [standard deviation] vs. 264.8 ± 22.4, mm) (all p<0.05). With multiple logistic regression, all of these CT parameters, except non-fibrotic ILD and kyphosis, remained significantly associated with GOLDU status (p<0.05). In cigarette smokers, chest wall abnormalities and parenchymal lung disease, which contribute to restrictive physiologic impairment, are associated with GOLD-nonobstructed status.

Visual Assessment of CT Findings in Smokers With Nonobstructed Spirometric Abnormalities in The COPDGene® Study

Within the COPD Genetic Epidemiology (COPDGene^®) study population of cigarette smokers, 9% were found to be unclassifiable by the Global Initiative for chronic Obstructive Lung Disease (GOLD) criteria. This study was to identify the differences in computed tomography (CT) findings between this nonobstructed (GOLDU) group and a control group of smokers with normal lung function. This research was approved by the institutional review board of each institution. CT images of 400 participants in the COPDGene^® study (200 GOLDU, 200 smokers with normal lung function) were retrospectively evaluated in a blinded fashion. Visual CT assessment included lobar analysis of emphysema (type, extent), presence of paraseptal emphysema, airway wall thickening, expiratory air trapping, centrilobular nodules, atelectasis, non-fibrotic and fibrotic interstitial lung disease (ILD), pleural thickening, diaphragmatic eventration, vertebral body changes and internal thoracic diameters (in mm). Univariate comparisons of groups for each CT parameter and multiple logistic regression were performed to determine the imaging features associated with GOLDU. When compared with the control group, GOLDU participants had a significantly higher prevalence of unilateral diaphragm eventration (30% vs. 16%), airway wall thickening, centrilobular nodules, reticular abnormality, paraseptal emphysema (33% vs. 17%), linear atelectasis (60% vs. 35.6%), kyphosis (12% vs. 4%), and a smaller internal transverse thoracic diameter (255 ± 22.5 [standard deviation] vs. 264.8 ± 22.4, mm) (all p<0.05). With multiple logistic regression, all of these CT parameters, except non-fibrotic ILD and kyphosis, remained significantly associated with GOLDU status (p<0.05). In cigarette smokers, chest wall abnormalities and parenchymal lung disease, which contribute to restrictive physiologic impairment, are associated with GOLD-nonobstructed status.

PP083. Clinic and out-of-clinic blood pressure changes during pregnancy by parity: Boshi study

INTRODUCTION

Nulliparity is believed to be one of the risk factors for hypertension during pregnancy. However, the relationship between parity and out-of-clinic blood pressure during pregnancy is still unknown.

OBJECTIVES

The aim of this study was to evaluate clinic blood pressure and blood pressure measured at home during pregnancy among nulliparous and multiparous women.

METHODS

This study was a prospective cohort study. We examined blood pressure measured in the clinic and at home among 530 normotensive pregnant women who received antenatal care at a maternity hospital in Japan. Clinic blood pressures were obtained by duplicate measurements at each antenatal care visit. The participants were also required to measure their own blood pressures every morning at home while they were pregnant. A linear mixed model was used for analysis of the blood pressure course throughout pregnancy [1]. The SAS package (version 9.2) was used for the statistical analyses.

RESULTS

A total of 315 nulliparous and 215 multiparous women were entered into this study (mean ages 30.1±4.6years and 33.0±4.1years, respectively). Clinic blood pressure during pregnancy among nulliparous women was significantly higher than that among multiparous women (P=0.02/P<0.0001 for systolic/diastolic blood pressure), whereas there were no significant differences in blood pressure measured at home during pregnancy between them (P=0.42/P=0.22 for systolic/diastolic blood pressure).

CONCLUSION

Out-of-clinic blood pressure levels during pregnancy have been shown not to differ between nulliparous and multiparous women, while clinic blood pressure during pregnancy among nulliparous women is higher than that among multiparous women.

Clinical efficacy and value of redistributed subclavian arterial infusion chemotherapy for locally advanced breast cancer

PURPOSE

The aim of this study was to evaluate the efficacy and safety of redistributed subclavian arterial infusion chemotherapy (RESAIC). We have focused on the local response, quality of life (QOL), and complications. We have also investigated factors that influence the local response of RESAIC.

MATERIALS AND METHODS

The subjects were patients with locally advanced breast cancer whose tumors were resistant to standard systemic chemotherapy (at least more than two regimens), those who were physically unable to tolerate systemic chemotherapy, and patients with locally recurrent breast cancer. The registration period was between April 2006 and May 2009.

RESULTS

A total of 24 cases in 22 patients (mean age 59.5 years, range 36-82 years) were entered in the study. The local response rate of RESAIC was 77.3% (17/22). The QOL score showed improvement on average. There were no serious complications during catheter port implantation, and there was hematological toxicity over grade 3 in 27.3% (6/22) of patients. A significant difference between responders and nonresponders was seen in patients with a replaced type tumor (on imaging, diffuse contrast enhancement was seen in whole quadrants) (P = 0.043), and the patients underwent radiotherapy (P = 0.043).

CONCLUSION

RESAIC is an effective, safe treatment for locally advanced breast cancer. Because it was reviewed in only a few cases, however, large-scale studies are warranted.

Correlation between airflow limitation and airway dimensions assessed by multidetector CT in asthma

BACKGROUND

Asthma is characterized by variable airflow obstruction and airway wall thickening. Multidetector-row computed tomography (MDCT) is useful for the evaluation of airway wall structural changes in asthma. The objective of the study is to assess the relationship between airflow limitation and airway dimensions from the third to fifth generation bronchi in asthma using MDCT.

METHODS

Thirty-eight subjects with asthma underwent MDCT to measure the airway wall area (WA) and luminal area (Ai), WA and Ai corrected by body surface area (BSA), up to the fifth generation of the apical bronchus (B1) and the posterior basal bronchus (B10) of the right lung.

RESULTS

WA/BSA, WA percentage (WA%) and Ai/BSA in the fifth generation were significantly correlated with forced expiratory volume in 1 s (FEV(1))% predicted. The correlation coefficients between WA% and FEV(1)% predicted increased when tracking the airways from the third to the fifth generation (r=-0.25, p>0.05; r=-0.40, p<0.01; r=-0.63, p<0.001 for B1; r=-0.23, p>0.05; r=-0.47, p<0.01; r=-0.69, p<0.001 for B10). At the generation 5, WA% was greater and Ai/BSA was smaller in severe asthma than mild-to-moderate asthma.

CONCLUSION

These results suggest that airway flow limitation in asthma is closely related to the more distal airways (third to fifth generation).

Demineralized dentin matrix acts as a scaffold for repair of articular cartilage defects

Articular cartilage repair remains a major obstacle in tissue engineering. In the present study, we investigated the potential for demineralized dentin matrix (DDM; organic material derived from dentin) obtained from extracted teeth to be used as bone graft material. To evaluate the extent to which DDM induces osteochondral regeneration, we implanted DDM from bovine teeth in rabbit knees with full-thickness articular cartilage defects. Thirty-three 13-week-old male rabbits weighing 2.5-3.0 kg were randomly assigned to a control group (n = 11) and two experimental groups (n = 11 for each group). The knees were divided into three groups according to the subsequent treatment: in group I (n = 22), the control group, the defect was left untreated; and in groups II (n = 22) and III (n = 22), 50 and 100 mg of DDM, respectively, was implanted. The rabbits were killed 1, 3, 6, or 9 weeks after the surgical procedure, and the knees were collected. The harvested tissues were examined radiographically and histologically. The 100-mg DDM group (group III) had significantly more new bone forming inside the defect (as measured using the BV/TV value) compared with the other two groups as early as at week 3 postoperatively, but thereafter, the difference gradually decreased. Cartilage repair in the surface region remained significantly better in group III because hyaline-like cartilage appeared in the peripheral area of the defect at week 6 and the surface was covered with hyaline-like cartilage with a thickness similar to that of normal cartilage at week 9. In conclusion, the results of this study suggest that DDM acts as a scaffold for osteochondral regeneration, yielding active new bone formation early in the postoperative period. Thus, DDM may represent an effective bone implant material.

Development of a new subclavian arterial infusion chemotherapy method for locally or recurrent advanced breast cancer using an implanted catheter-port system after redistribution of arterial tumor supply

Locally or recurrent advanced breast cancers can receive arterial blood supply from various arteries, such as the internal thoracic artery (ITA), the lateral thoracic artery, and the other small arterial branches originating from the subclavian artery. Failure to catheterize and subsequent formation of collateral arterial blood supply from various arteries are some of the reasons why the response to conventional selective transarterial infusion chemotherapy is limited and variable. To overcome this problem, we developed a new subclavian arterial infusion chemotherapy method using an implanted catheter-port system after redistribution of arterial tumor blood supply by embolizing the ITA. We named this technique ("redistributed subclavian arterial infusion chemotherapy" (RESAIC)). Using RESAIC, patients can be treated on an outpatient basis for extended periods of time. Eleven patients underwent RESAIC, and the complete remission and partial response rate in 10 evaluable patients was 90%: complete remission [CR] n = 4, partial remission n = 4, stable disease n = 1, and not evaluable n = 1. Three of four patients with CR had no distant metastasis, and modified radical mastectomy was performed 1 month after conclusion of RESAIC. The resected specimens showed no residual cancer cells, and pathologically confirmed complete remission was diagnosed in each of these cases. Although temporary grade-3 myelosuppression was seen in three patients who were previously treated by systemic chemotherapy, there was no other drug-induced toxicity or procedure-related complications. RESAIC produced a better response and showed no major complications compared with other studies despite the advanced stage of the cancers.

Airway dimensions at inspiratory and expiratory multisection CT in chronic obstructive pulmonary disease: correlation with airflow limitation

PURPOSE

To analyze the relationship between airflow limitation and airway dimensions from the third to the fifth generation of bronchi in patients with chronic obstructive pulmonary disease (COPD) by using inspiratory and expiratory multisection computed tomography (CT).

MATERIALS AND METHODS

This retrospective study was approved by the institutional review board, which waived the need for informed consent. The study included 50 patients with COPD who underwent both inspiratory and expiratory 64-detector CT. In each patient, mean values of airway luminal areas from the third to the fifth generation of three bronchi (right B1, right B10, and left B3) were measured at inspiratory CT (IA3, IA4, and IA5) and expiratory CT (EA3, EA4, and EA5). To evaluate the change of the airway luminal area between inspiration and expiration, the ratio of expiratory to inspiratory airway luminal area in each generation was calculated (EA3/IA3, EA4/IA4, and EA5/IA5). Correlations between airway dimensions and pulmonary function test results were evaluated.

RESULTS

The correlation coefficients between airway luminal area measured at expiratory CT and the forced expiratory volume in 1 second (FEV(1)) were higher than those for inspiratory CT and improved as the airway size decreased from the third to the fifth generation (IA3, r = .02; IA4, r = .18; IA5, r = .26; EA3, r = .09; EA4, r = .40; EA5, r = .63). EA5/IA5 had the highest correlations with FEV(1) (r = .72, P < .001). There were no significant correlations between EA3/IA3 and pulmonary function test results.

CONCLUSION

Airway lumen measured at expiratory CT was more closely related to expiratory airflow measurements than was lumen measured at inspiratory CT. In addition, the changes of airway luminal area between inspiration and expiration were strongly related to airflow limitation.

Percutaneous vertebroplasty performed by the isocenter puncture method

PURPOSE

The aim of this study was to clarify the usefulness of the isocenter puncture (ISOP) method.

MATERIALS AND METHODS

We investigated 73 vertebral bodies that had undergone percutaneous vertebroplasty (PVP) by the ISOP method, 118 vertebral bodies that had undergone the puncture simulation method, and 33 vertebral bodies that had undergone the conventional method. The items to be examined included the success rate (SR) of the median puncture of the vertebral body and the procedure time. The puncture accuracy and fluoroscopy time were also measured for the ISOP method.

RESULTS

The SR was significantly higher and the procedure time significantly shorter when using the ISOP method rather than the conventional method. However, no significant differences were observed between the ISOP method and the puncture simulation method. The errors between the puncture needle tip and the puncture target point in the ISOP method were an average of 1.52, 2.08, and 1.87 mm in each of the horizontal, ventrodorsal, and craniocaudal directions. The fluoroscopy time when operating on one vertebral body was an average of 5.8 min.

CONCLUSION

The ISOP method is considered to be a useful approach while also reducing the puncture time and the fluoroscopy time.

Quantitative assessment of peripheral airway obstruction on paired expiratory/inspiratory thin-section computed tomography in chronic obstructive pulmonary disease with emphysema

OBJECTIVES

We examined the hypothesis that paired inspiratory/expiratory computed tomography (CT) scans in a limited-lung area that excludes emphysema may provide a more accurate evaluation of peripheral airway obstruction in patients with chronic obstructive pulmonary disease (COPD) with emphysema.

MATERIALS AND METHODS

This study included 32 patients with COPD. The cross-sectional area between -500 and -1024 HU was segmented as whole-lung. The relative areas (RA) less than -950 HU for the whole-lung (RA<-950) were segmented as emphysema, and pixels less than -900 HU for the whole-lung (RA<-900) were segmented to evaluate air trapping. Next, the cross-sectional area between -500 and -950 HU that excludes emphysema was segmented as limited-lung, and pixels between -900 and -950 HU for the limited-lung (RA900-950) were segmented. The changes in RA<-900 (RA<-900-change) and RA900-950 (RA900-950-change) between inspiration and expiration were calculated. Correlations between CT measurements and the results of pulmonary function tests (PFT) were evaluated.

RESULTS

There was no significant difference between the mean inspiratory RA<-950 and expiratory RA<-950 (P = 0.245), but the mean expiratory RA900-950 decreased significantly compared with the mean inspiratory RA900-950 (P < 0.001). The correlation coefficients between PFT parameters and the RA900-900-change in the limited-lung without emphysema were higher than that of the RA<-900-change in the whole-lung.

CONCLUSIONS

The paired inspiratory/expiratory CT measurements in the limited-lung without emphysema correlated more closely with the PFTs. Our observations suggest that paired inspiratory/expiratory CT scans in the limited-lung excluding emphysema are sensitive for the evaluation of airway obstruction in COPD with emphysema.

Quantitative Thin-Section CT Analysis of the Enlargement and Coalescence of Low-Attenuation Clusters in Patients with Emphysema

BACKGROUND

The analysis of the number and size of low-attenuation clusters has been adopted as quantitative computed tomography (CT) analysis of emphysema; however, a detailed examination has not been made on the relation between the number of various cluster sizes and the extent of emphysema.

OBJECTIVE

The aim of this study was to evaluate the relationship between the size and number of clusters on CT scans in patients with emphysema.

METHODS

This retrospective study included 31 emphysema patients. The number (LAN) and mean size (LAS) of clusters below -950 HU, and relative low-attenuation area below -950 HU (RA950) were calculated using an image-processing program. The size of clusters was divided into 3 categories, and the number in each size category was obtained as follows: small (sLAN 0.4-8 mm(2)), medium (mLAN 8.4-40 mm(2)), and large (lLAN >40 mm(2)). The relationships between the RA950 and sLAN, mLAN, or lLAN were evaluated. Patients were divided according to the extent of RA950 (>25% = severe emphysema, <25% = mild emphysema), and the relations between RA950 and LAN, and between RA950 and sLAN, mLAN, or lLAN were evaluated.

RESULTS

The sLAN decreased as RA950 increased (r = -0.477), whereas mLAN and lLAN increased (r = 0.421, and r = 0.819). In severe emphysema, sLAN and mLAN decreased as RA950 increased (r = -0.722, and r = -0.698). In mild emphysema, mLAN and lLAN increased as RA950 increased (r = 0.732, and r = 0.972).

CONCLUSIONS

The degree of the coalescence of the clusters depends on the size of clusters and the extent of emphysema. Quantitative CT analyses of clusters are helpful to elucidate the pathophysiology and progressive nature of emphysema.

Morphological Progression of Emphysema on Thin-section CT

OBJECTIVES

To evaluate morphological changes in the number and size of low-attenuation clusters on computed tomography (CT) in patients with emphysema.

MATERIALS AND METHODS

In 27 patients who had follow-up CT scans for 6 months or greater, initial 27 scans and follow-up 39 scans were analyzed. The number per slice (LAN/s) and mean size (LAS) of low-attenuation clusters less than -950 HU, and total low-attenuation area below -950 HU per slice (LAA-950/s) were calculated.

RESULTS

LAS and LAA-950/s were significantly increased over time. No significant correlation was found between LAN/s and follow-up period. LAS increased in 37 of 39 (95%) follow-up scans, whereas LAN/s decreased in 17 of 39 (44%) follow-up scans.

CONCLUSIONS

On the morphological progression of emphysema, the mean size of low-attenuation clusters was significantly increased during the follow-up period, whereas no significant correlation was found between the number of low-attenuation clusters and follow-up period.

Quantification of Thin-Section CT Lung Attenuation in Acute Pulmonary Embolism: Correlations with Arterial Blood Gas Levels and CT Angiography

OBJECTIVE

The purposes of this study were to investigate the frequency histogram of lung attenuation on CT angiography (CTA) in patients with and without acute pulmonary embolism (PE) and to evaluate the relation of the frequency histogram of lung attenuation and hypoxemia.

MATERIALS AND METHODS

Twenty-six patients with PE and 11 patients without PE who underwent CTA were evaluated with frequency histograms. We obtained quantitative parameters such as mean lung attenuation, median lung attenuation, SD, skewness, kurtosis, and the proportion of lung attenuation except for the median +/- 50 H (P +/- 50 H). Lung attenuation was also assessed visually and scored. The relationship between those histogram parameters, or visual score, and Pa(O2) was evaluated. CTA scores for evaluation of the degree of pulmonary artery obstruction were obtained, and the relation with Pa(O2) was assessed.

RESULTS

No significant differences were found in mean lung attenuation and median lung attenuation between patients with and without PE. Meanwhile, SD, skewness, kurtosis, and P +/- 50 H were significantly different between patients with and without PE (p = 0.0003, 0.0071, 0.0047, and 0.0028, respectively) and significantly correlated with Pa(O2) (r = -0.770, 0.797, 0.786, -0.871, respectively). Significant differences were found in visual scores between patients with and without PE (p < 0.0001). There were significant but relatively low correlations between CTA score and arterial blood gas levels (r = -0.442, p = 0.03).

CONCLUSION

In patients with acute PE, heterogeneity in lung attenuation is more prominent than in patients without PE.

Thin-section CT assessment of spontaneous pneumomediastinum in interstitial lung disease: correlation with serial changes in lung parenchymal abnormalities

PURPOSE

The purpose of this study was to analyze thin-section computed tomography (CT) appearances of interstitial lung diseases before and at the time of detection of pneumomediastinum, and to evaluate the relationship between pneumomediastinum and parenchymal changes on thin-section CT.

MATERIALS & METHODS

We reviewed CT images before and at the time of detection of pneumomediastinum in 13 patients with idiopathic pulmonary fibrosis (8 patients) and collagen vascular diseases (5 patient). The extent of the total area of reticular opacity, increased opacity (ground-glass opacity and consolidation), and honeycombing were scored, and these scores were compared before and at the time of detection of pneumomediastinum. We also divided patients into two groups according to therapy received. Patients in group 1 experienced pneumomediastinum after or during treatment with corticosteroids or immunosuppressive agents for acute or subacute exacerbation of interstitial lung disease. Patients in group 2 experienced pneumomediastinum without therapy.

RESULTS

The mean score of all patients for honeycombing significantly increased at the time of detection of pneumomediastinum (P=0.003). In group 1, the extent of increasing opacity had been decreased significantly at the time of detection of pneumomediastinum (P=0.028). In group 2, the mean CT score of reticular opacity, increasing opacity, and honeycombing significantly increased at the time of detection of pneumomediastinum (P=0.028, 0.018, and 0.018, respectively).

CONCLUSIONS

Spontaneous pneumomediastinum associated with interstitial lung disease appears to have a tendency to occur under conditions of altered of parenchymal interstitial lesions.

Peripheral solitary pulmonary nodule: CT findings in patients with pulmonary emphysema

PURPOSE

To analyze retrospectively the computed tomographic (CT) features of peripheral noncalcified solitary pulmonary nodules in patients with and those without emphysema.

MATERIALS AND METHODS

The authors' institutional review board required neither its approval nor patient informed consent for this retrospective study. The authors retrospectively reviewed 2-mm-thick CT images of 41 nodules (21 malignant, 20 benign) in 41 patients with emphysema (age range, 58-88 years; mean, 71.9 years) and 40 nodules (20 malignant, 20 benign) in 40 patients without emphysema (age range, 50-85 years; mean, 69.2 years). Two radiologists who were unaware of the diagnosis independently evaluated the shape and margin of the nodule, recorded the presence of ground-glass opacities and air bronchograms, and classified nodules into two diagnostic categories: malignant and benign. Final decisions were reached by consensus. For quantitative assessment of the nodules, the fractal dimensions of the nodule interfaces and circularity of the nodule shape were calculated with an image-processing program, and the percentage of the nodule surrounded by emphysema was obtained. Statistical comparisons were made with a chi(2) or Fisher exact test and the Mann-Whitney U test.

RESULTS

In patients with emphysema, there were no significant differences in fractal dimension, circularity, or frequency of lobulation or spiculation between malignant and benign nodules. Of the 41 nodules in patients with emphysema, 26 (63%) were correctly diagnosed. Thirteen benign nodules (65%) were diagnosed as malignant in patients with emphysema. Of the 40 nodules in nonemphysematous lungs, 37 (93%) were correctly diagnosed. The mean percentage of emphysema around the nodule was greater for misdiagnosed nodules than for correctly diagnosed nodules (P = .003).

CONCLUSION

Malignant and benign nodules associated with emphysema exhibited considerably more overlap in CT features than did nodules in nonemphysematous lungs.