Kiminori Fujimoto

Interobserver Variability in the CT Assessment of Honeycombing in the Lungs

PURPOSE To quantify observer agreement and analyze causes of disagreement in identifying honeycombing at chest computed tomography (CT). MATERIALS AND METHODS The institutional review board approved this multiinstitutional HIPAA-compliant retrospective study, and informed patient consent was not required. Five core study members scored 80 CT images with a five-point scale (5 = definitely yes to 1 = definitely no) to establish a reference standard for the identification of honeycombing. Forty-three observers from various subspecialties and geographic regions scored the CT images by using the same scoring system. Weighted κ values of honeycombing scores compared with the reference standard were analyzed to investigate intergroup differences. Images were divided into four groups to allow analysis of imaging features of cases in which there was disagreement: agreement on the presence of honeycombing, agreement on the absence of honeycombing, disagreement on the presence of honeycombing, and other (none of the preceding three groups applied). RESULTS Agreement of scores of honeycombing presence by 43 observers with the reference standard was moderate (Cohen weighted κ values: 0.40-0.58). There were no significant differences in κ values among groups defined by either subspecialty or geographic region (Tukey-Kramer test, P = .38 to >.99). In 29% of cases, there was disagreement on identification of honeycombing. These cases included honeycombing mixed with traction bronchiectasis, large cysts, and superimposed pulmonary emphysema. CONCLUSION Identification of honeycombing at CT is subjective, and disagreement is largely caused by conditions that mimic honeycombing.

Periostin, a matrix protein, is a novel biomarker for idiopathic interstitial pneumonias

Idiopathic interstitial pneumonias (IIPs) are histopathologically classified into several types, including usual interstitial pneumonia (UIP), nonspecific interstitial pneumonia (NSIP) and cryptogenic organising pneumonia (COP). We investigated whether periostin, a matrix protein, could be used as a biomarker to assess histopathological types of IIPs. We performed immunohistochemical analyses in each histopathological type of IIP, examined serum levels of periostin in IIP patients and analysed the relationship between serum levels of periostin and the pulmonary functions in patients with idiopathic pulmonary fibrosis (IPF). Periostin was strongly expressed in lungs of UIP and fibrotic NSIP patients, whereas expression of periostin was weak in the lungs of cellular NSIP and COP patients, as well as in normal lungs. Serum levels of periostin in IPF were significantly higher than those of healthy subjects and COP patients. Furthermore, periostin levels in IPF patients were inversely correlated with their pulmonary functions. Thus, we have found that periostin is a novel component of fibrosis in IIP. Periostin may be a potential biomarker to distinguish IIP with fibrosis.

Lung Cyst Formation in Lymphocytic Interstitial Pneumonia: Ct Features

Objective We performed this study to identify and characterize the CT findings of lymphocytic interstitial pneumonia (LIP). Materials and Methods The CT findings of two patients with LIP were reviewed and correlated with their histologic specimens. Results Chest CT of the two patients showed areas of increased attenuation in both lung fields which were associated with nodular and cystic lesions surrounding the peribronchovascular bundles. The most characteristic abnormality identified on CT was the presence of multiple cysts throughout both lungs. Macroscopic findings of lung biopsy specimens included multiple nodular and cystic lesions. Conclusion This description of multiple pulmonary cysts formation in LIP is new.

Dynamic MRI of Solitary Pulmonary Nodules: Comparison of Enhancement Patterns of Malignant and Benign Small Peripheral Lung Lesions

OBJECTIVE The purpose of this study was to compare the dynamic contrast-enhanced MRI enhancement characteristics of malignant and benign solitary pulmonary nodules. MATERIALS AND METHODS The characteristics of 202 solitary pulmonary nodules (diameter, 1-3 cm; 144 cases of primary lung cancer, 31 cases of focal organizing pneumonia, 15 tuberculomas, 12 hamartomas) were reviewed retrospectively. In all cases dynamic MR images were obtained before and 1, 2, 3, 4, 5, 6, and 8 minutes after bolus injection of gadopentetate dimeglumine. Maximum enhancement ratio, time at maximum enhancement ratio, slope of time-enhancement ratio curves, and washout ratio were assessed. Statistical analyses were performed with the Kruskal-Wallis test with Bonferroni correction, chi-square test, and receiver operating characteristic curves. RESULTS For 122 (85%) of 144 primary lung cancers, time at maximum enhancement ratio was 4 minutes or less. For all tuberculomas and hamartomas, time at maximum enhancement ratio was greater than 4 minutes or gradual enhancement occurred without a peak time (p < 0.0001). Lung cancers had different maximum enhancement ratios and slopes than benign lesions (all p < 0.005). With 110% or lower maximum enhancement ratio as a cutoff value, the positive predictive value for malignancy was 92%; sensitivity, 63%; and specificity, 74%. With 13.5%/min or greater slope as a cutoff value, sensitivity, specificity, positive predictive value, and negative predictive value for malignancy were 94%, 96%, 99%, and 74%, respectively. CONCLUSION Dynamic contrast-enhanced MRI is helpful in differentiating benign from malignant solitary pulmonary nodules. Absence of significant enhancement is a strong predictor that a lesion is benign.

Acute Exacerbation of Chronic Interstitial Pneumonia: High-resolution Computed Tomography and Pathologic Findings

Purpose To review the high-resolution computed tomography (CT) and histologic findings of acute exacerbation of chronic interstitial pneumonia and to assess the potential value of CT and histologic findings in predicting prognosis. Materials and Methods The study included 24 patients with clinical and histologic diagnosis of acute exacerbation of chronic interstitial pneumonia who underwent CT within 1 month before biopsy or autopsy. The final diagnosis was acute exacerbation of idiopathic pulmonary fibrosis (n=12), usual interstitial pneumonia associated with connective tissue disorders (n=5), idiopathic nonspecific interstitial pneumonia (n=4), and nonspecific interstitial pneumonia associated with connective tissue disorders (n=3). Results The main CT findings consisted of bilateral ground-glass opacities (100%) and consolidation (71%) superimposed on a reticular pattern. The ground-glass opacities and/or consolidation were diffuse in 54% of the cases, multifocal in 21%, and peripheral in 25%. The histologic patterns of acute injury consisted of diffuse alveolar damage (n=20), acute organizing pneumonia (OP) (n=3), and extensive fibroblastic foci (n=1). Eight (33%) patients survived the acute episode, including all 3 patients with OP and the patient with extensive fibroblastic foci (P=0.01). The survivors included 3 of 13 (23%) patients with diffuse parenchymal opacification, 2 of 5 (40%) patients with multifocal, and 3 of 6 (50%) patients with peripheral opacification on CT. Conclusions The CT findings of acute exacerbation of chronic interstitial pneumonia consist of diffuse, multifocal, or peripheral parenchymal opacification superimposed on reticulation. Histologic findings of OP are superior to CT in predicting prognosis.

Evaluation of the mean and entropy of apparent diffusion coefficient values in chronic hepatitis C: Correlation with pathologic fibrosis stage and inflammatory activity grade

PURPOSE To determine whether mean and entropy apparent diffusion coefficient (ADC) values obtained at diffusion-weighted (DW) magnetic resonance (MR) imaging can help detect and stage histopathologic liver fibrosis and grade inflammation activity in patients with chronic hepatitis C. MATERIALS AND METHODS This retrospective study was approved by the institutional review board, and the requirement for informed consent was waived. The study included 55 patients with focal hepatic lesions and either chronic hepatitis C (n = 43) or normal hepatic function (control subjects) (n = 12). Mean and entropy of volume histograms were generated in four cubic regions of interest placed in the right hepatic lobe of ADC map images, which were obtained at echo-planar DW MR imaging (gradient factor b values of 0 and 1000 sec/mm(2)). These two parameters (mean and entropy ADC) were compared by using METAVIR histopathologic liver fibrosis and inflammatory activity scores. Statistical analysis was performed with the Kruskal-Wallis test and receiver operating characteristic curves. RESULTS The mean ADC decreased with an increase in the fibrosis stage or inflammatory activity grade, and the entropy ADC increased with an increase in the fibrosis stage or inflammatory activity grade (P < .001 for all comparisons, Kruskal-Wallis test). The area under the receiver operating characteristic curve (A(z)) for the mean ADC was statistically significant in the differentiation of fibrosis stage or inflammatory activity grade (A(z), 0.807-0.926; P < .001 for all comparisons). Entropy of ADC was helpful for classifying normal from abnormal fibrosis stage or inflammatory activity grade (A(z) for both parameters, 0.937; P < .001). CONCLUSION Assessment of a combination of mean ADC and entropy ADC in patients with chronic hepatitis C is more accurate for predicting pathologic hepatic fibrosis stage and inflammatory activity grade and helpful for detecting early fibrotic or inflammatory activity when compared with assessment of mean ADC alone.

Churg-Strauss syndrome: high resolution CT and pathologic findings.

Objectives: The purpose of this study was to evaluate high-resolution CT findings in 7 patients with Churg-Strauss syndrome and to compare the CT with the histopathologic findings. Materials and Methods: High-resolution CT scans of 7 asthmatic patients (4 women, 3 men, age range, 34-62 years, mean 49 years) with Churg-Strauss syndrome were reviewed by 2 observers. Histologic specimens of lung obtained at surgical (n = 3) or transbronchial (n = 3) biopsy or autopsy (n = 1) were reviewed by an expert lung pathologist. The diagnosis of Churg-Strauss was based on clinical, laboratory, and histologic findings. Results: Parenchymal and airway abnormalities included ground-glass opacities (n = 5), areas of air-space consolidation (n = 4), centrilobular nodules (n = 5), nodules 1-3 cm in diameter (n = 3), interlobular septal thickening (n = 4), bronchial wall thickening (n = 4), and areas of atelectasis (n = 1). Surgical biopsy (n = 3) and autopsy (n = 1) specimens demonstrated airspace disease in 3 patients, interlobular septal thickening in 3 patients, and airway abnormalities in 2 patients. Histologically, the airspace disease included eosinophilic pneumonia (n = 2) and small foci of organizing pneumonia (n = 1). The septal thickening was due to edema combined with numerous (n = 2) or few (n = 1) eosinophils. The airway abnormalities (n = 2) included muscle hypertrophy and large airway wall necrosis (n = 1) and eosinophilic infiltration of the airway walls (n = 1). Transbronchial biopsy (n = 3) demonstrated increased eosinophils. Conclusion: The main high-resolution CT findings of Churg-Strauss syndrome consist of airspace consolidation or ground-glass opacities, septal lines, and bronchial wall thickening. These reflect the presence of eosinophilic infiltration of the airspaces, interstitium, and airways, and interstitial edema.

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

AbstractObjectivesTo determine high-resolution computed tomography (HRCT) findings helpful in predicting mortality in patients with acute exacerbation of idiopathic pulmonary fibrosis (AEx-IPF).MethodsSixty patients with diagnosis of AEx-IPF were reviewed retrospectively. Two groups (two observers each) independently evaluated pattern, distribution, and extent of HRCT findings at presentation and calculated an HRCT score at AEx based on normal attenuation areas and extent of abnormalities, such as areas of ground-glass attenuation and/or consolidation with or without traction bronchiectasis or bronchiolectasis and areas of honeycombing. The correlation between the clinical data including the HRCT score and mortality (cause-specific survival) was evaluated using the univariate and multivariate Cox-regression analyses.ResultsSerum KL-6 level, PaCO2, and the HRCT score were statistically significant predictors on univariate analysis. Multivariate analysis revealed that the HRCT score was an independently significant predictor of outcome (hazard ratio, 1.13; 95% confidence interval, 1.06–1.19, P = 0.0002). The area under receiver operating characteristics curve for the HRCT score was statistically significant in the classification of survivors or nonsurvivors (0.944; P < 0.0001). Survival in patients with HRCT score ≥245 was worse than those with lower score (log-rank test, P < 0.0001).ConclusionThe HRCT score at AEx is independently related to prognosis in patients with AEx-IPF. Key Points •High-Resolution Computed Tomography (HRCT) helps clinicians to assess patients with interstitial fibrosis. •The main abnormalities of acute exacerbation are ground-glass opacification and consolidation. •Extent of abnormalities on HRCT correlates with poor prognosis.

MRI of ganglioneuroma: Histologic correlation study

Purpose The purpose of this study was to evaluate the MR findings of ganglioneuroma and to correlate imaging and histologic features. Method Conventional SE and contrast-enhanced dynamic MRI was used to examine 10 patients with pathologically confirmed ganglioneuroma. The morphologic features, signal intensity, and dynamic enhancement pattern of the tumors were retrospectively analyzed and correlated with histologic features. Results Capsules were present in all tumors histologically and were also detected in five tumors on postcontrast T1-weighted images. A whorled appearance corresponding to interlacing bundles of Schwann cells and collagen fibers on histologic specimens was visualized in five tumors on T1-and/or T2-weighted images. Tumors with markedly high signal intensity on T2-weighted images consisted histologically of a large amount of myxoid stroma and relatively few cellular and fibrous components. Tumors with intermediate to high signal intensity consisted of numerous cellular and fibrous components and little myxoid stroma. Early enhancement of tumors was usually lacking in dynamic MR studies; however enhancement gradually increased. Conclusion The results suggest that the MR features of ganglioneuroma are well correlated with histologic findings.

Differentiation between Birt–Hogg–Dubé syndrome and lymphangioleiomyomatosis: Quantitative analysis of pulmonary cysts on computed tomography of the chest in 66 females

BACKGROUNDS Since Birt-Hogg-Dubé syndrome (BHDS) and lymphangioleiomyomatosis (LAM) share some clinical manifestations (multiple pulmonary cysts with pneumothorax, renal tumors, and sometimes skin lesions), the differential diagnosis of the two diseases becomes problem especially in female patients. This study aims to quantify pulmonary cysts in computed tomography (CT) of females with BHDS and those with LAM and also to identify the independent parameters for differentiating the two diseases. METHODS Fourteen patients with BHDS and 52 with LAM were studied. In CT scans, lung fields were defined as areas with fewer than -200 Hounsfield units (HU) and pulmonary cysts as areas consisting of 10 or more consecutive pixels with fewer than -960 HU. The extent, number, size and circularity of cysts were calculated by using hand-made software and compared between the two diseases. Moreover, the lung fields were divided into six zones and analyzed for the distribution of cysts. Finally, a stepwise discriminant analysis employing quantitative measurements of cysts and clinical features was performed. RESULTS The two diseases were significantly different in all quantitative measurements of cysts. Stepwise discriminant analysis accepted the following four variables: the family history of pneumothorax within the second degree relatives, lower-medial zone predominance of cysts, diffusing capacity and mean size of cysts in this order. CONCLUSION The quantitative characteristics of pulmonary cysts are significantly different between BHDS and LAM. The independent parameters for differentiating the two diseases are the family history of pneumothorax, zonal predominance of cysts, diffusing capacity and size of cysts.