Radiologic Approach for Pulmonary Vasculitis

Vasculitis is a systemic disease, characterized by inflammation of the vascular wall. Although rare, it is sometimes life-threatening due to diffuse pulmonary hemorrhage or acute glomerulonephritis. Besides primary vasculitis, whose cause is unknown, numerous conditions such as autoimmune diseases, drugs, infections, and tumors can cause secondary vasculitis. Vasculitis displays various non-specific symptoms, signs, and laboratory findings; hence, diagnosis of the disease requires integration of various results including clinical features, imaging findings, autoantibody tests, and pathological findings. In this review, we have discussed the clinical, radiologic, and pathological features of vasculitis. Further, we elaborated the imaging findings and differential diagnosis of typical vasculitis that frequently involves the lung and introduced a new international classification of vasculitis, the Diagnostic and Classification Criteria in Vasculitis.

Radiologic Approach for Pulmonary Vasculitis

Vasculitis is a systemic disease, characterized by inflammation of the vascular wall. Although rare, it is sometimes life-threatening due to diffuse pulmonary hemorrhage or acute glomerulonephritis. Besides primary vasculitis, whose cause is unknown, numerous conditions such as autoimmune diseases, drugs, infections, and tumors can cause secondary vasculitis. Vasculitis displays various non-specific symptoms, signs, and laboratory findings; hence, diagnosis of the disease requires integration of various results including clinical features, imaging findings, autoantibody tests, and pathological findings. In this review, we have discussed the clinical, radiologic, and pathological features of vasculitis. Further, we elaborated the imaging findings and differential diagnosis of typical vasculitis that frequently involves the lung and introduced a new international classification of vasculitis, the Diagnostic and Classification Criteria in Vasculitis.

Effects of Blue Light on Eye of Zebra Fish and Protective Role of Polyphenolic Compounds

Purpose@#To investigate the oxidative damage and changes of retinas by blue light through zebrafish and to confirm the protective effect of polyphenol on retina cells using grape seed-derived polyphenols. @*Methods@#To induce oxidative damage and changes of the retina by blue light, blue light LED (10,000 Lux, 480 nm) was added to the zebrafish grown in the dark room after pretreating polyphenols derived from grape seed at various concentrations (0, 0.1, 1, 10 μg/mL, respectively) for 4 days. Changes in retinal thickness and numbers of outer nuclear layer nuclei through hematoxylin & eosin staining were evaluated. @*Results@#Photoreceptor layer thickness of blue light exposed group was significantly thinner than the group without blue light (108.1 ± 27.7 μm vs 41.1 ± 17.0 μm). As pretreated polyphenol concentration increased, photoreceptor layer thickness was increased (41.1 ± 17.0, 56.3 ± 18.6, 90.7 ± 23.7, 99.1 ± 23.1 μm, p < 0.05), and damage to outer nuclear layer nuclei was also decreased. @*Conclusions@#Exposure to blue light is an important factor for increasing oxidative stress in the retina. Grape seed-derived polyphenols have been shown to protect photoreceptor cells and retinal pigment epithelial cells from oxidative stress. This suggests that the antioxidant effect of polyphenol compounds may help suppress the progression of retinal diseases associated with oxidative stress such as age-related macular degeneration.

Anti-staphylococcal Effect of a Nephrite-containing Contact Lens Storage Case

Purpose@#To compare the anti-staphylococcal effect of nephrite-containing contact lens (CL) storage cases and conventional CLstorage cases.Method: The degree of proliferation and adhesion of Staphylococcus aureus (S. aureus) on first- to third-generation silicone hydrogelcontact lenses (SHCLs) was analyzed through comparison of 5% nephrite-containing CL storage cases and conventionalCL storage cases. The degree of adhesion of S. aureus to the CL was also compared between 1% or 5% nephrite solution andmultipurpose solution (MPS).Result: Nephrite-containing CL storage cases showed a significant inhibitory effect on S. aureus proliferation (p = 0.004) and significantlyreduced the number of adherent S. aureus on all first- to third generation SHCLs compared with conventional CL storagecases (p = 0.026, p = 0.043, and p = 0.001, respectively). The anti-staphylococcal effect of 1% and 5% nephrite solutionswas not significantly better than that of MPS. @*Conclusions@#Nephrite shows potential as a next-generation substance for reducing infectious keratitis caused by S. aureuswhen added to CL storage cases.

2018 Korean Clinical Imaging Guideline for Hemoptysis

In 2014, the American College of Radiology (ACR) announced the guideline for the appropriate diagnostic approach and treatment of patients according to the severity of hemoptysis and risk for lung cancer. However, the application of the ACR guideline in Korea may not be appropriate, because many patients in Korea have active tuberculosis or pulmonary fibrosis due to previous tuberculosis. The Korean Society of Radiology and Korean Society of Thoracic Radiology have proposed a new guideline suitable for Korean practice. This new guideline was prepared through the consensus of a development committee, working party, and an advisory committee. The guideline proposal process was based on an evidence-based clinical imaging guideline proposed by the development committee. Clinical imaging guideline for adult patients with hemoptysis is as follows: Chest radiography is an initial imaging modality to evaluate hemoptysis. Contrast-enhanced chest CT is recommended in patients with two risk factors for lung cancer (> 40 years old and > 30 pack-year smoking history), moderate hemoptysis (> 30 mL/24 hours) or recurrent hemoptysis. Contrast-enhanced chest CT is also recommended in patients with massive hemoptysis (> 400 mL/24 hours) without cardiopulmonary compromise.

Korean Clinical Imaging Guideline for Hemoptysis

In 2014, the American College of Radiology announced a guideline for appropriate diagnostic approach and treatment in patients with hemoptysis, according to severity of hemoptysis and risk of lung cancer. However, in Korea many patients have pulmonary fibrosis due to previous tuberculosis or have active tuberculosis. Therefore, application of this guideline is not appropriate. The Korean Society of Radiology and Korean Society of Thoracic Radiology proposed a guideline more closely matching the real state of diagnostic approach and treatment of patients with hemoptysis in Korea. The guideline was prepared in consensus by a development committee, working party, and an advisory committee. The process of the guideline proposal was based on methodology for developing evidence-based clinical imaging guidelines: joint recommendations by the Korean Society of Radiology and National Evidence-Based Healthcare Collaborating Agency. The clinical imaging guideline for adult patients with hemoptysis is as follows. Chest radiography is an initial imaging modality to evaluate hemoptysis. Contrast enhanced chest CT is recommended in patients with two lung cancer risks (> 40 years old and > 30 packs per year smoking history), moderate hemoptysis (> 30 cc/24 hours) or recurrent hemoptysis. Contrast enhanced chest CT is also recommended for patients with massive hemoptysis (> 400 mL/24 hours) without cardiopulmonary compromise.

Erratum: Korean Clinical Imaging Guideline for Hemoptysis

On page 83 and 85, there were repeated typographical error of foot note in Table 2, Table 3, and Table 4. We have revised “adated” to “adapted.”

Nestin Expression in the Adult Mouse Retina with Pharmaceutically Induced Retinal Degeneration

The present study investigated the temporal pattern and cellular localization of nestin in the adult mouse retina with pharmaceutically induced retinal degeneration using N-methyl-N-nitrosourea (MNU). After a single intraperitoneal injection of MNU in 8-week-old C57BL/6 mice, the animals were sacrificed at 1, 3, 5, 7, and 21 days (n = 6, in each stage). The eyes were examined by means of immunohistochemical tests using nestin, ionized calcium-binding adaptor molecule (Iba-1), CD11b, F4/80, and glial fibrillary acidic protein (GFAP). Western blot analysis and manual cell counting were performed for quantification. Nestin expression was increased after MNU administration. Nestin+/Iba-1+ cells were migrated into outer nuclear layer (ONL) and peaked at day 3 post injection (PI). Nestin+/CD11b+ cells were also mainly identified in ONL at day 3 PI and peaked at day 5. Nestin+/F4/80+ cells were shown in the subretinal space and peaked at day 3 PI. Nestin+/GFAP+ cells were distinctly increased at day 1 PI and peaked at day 5 PI. The up-regulation of nestin expression after MNU administration in adult mouse retinal microglia, and monocyte/macrophage suggests that when retinal degeneration progresses, these cells may revert to a more developmentally immature state. Müller cells also showed reactive gliosis and differentiational changes.

Amoebicidal Effect of Nephrite-containing Contact Lens Storage Case

PURPOSE: To compare the amoebicidal effects of nephrite containing contact lens (CL) storage cases with conventional CL storage cases. METHODS: Acanthamoeba lugdunensis were inoculated onto 5% nephrite containing CL storage cases as well as conventional CL storage cases both with and without silicone hydrogel contact lenses (SHCLs). Then the amount of Acanthamoeba proliferation on CL storage cases and the number of adherent Acanthamoeba on SHCLs were determined and compared. The effects of multipurpose solution (MPS) with and without 1% or 5% nephrite solution on Acanthamoeba adhesion were analyzed. RESULTS: Nephrite containing CL storage cases showed more inhibitory effects on Acanthamoeba proliferation (p = 0.02) and significantly reduced the number of adherent Acanthamoeba on SHCLs compared with conventional CL storage cases, regardless of SHCLs generation (p = 0.001, p = 0.001 and p < 0.001, respectively). The number of adherent Acanthamoeba on the first generation of SHCLs was significantly reduced by MPS with 1% and 5% nephrite solutions (p = 0.03 and p = 0.004, respectively), but the numbers for the second and third generation SHCLs were not. CONCLUSIONS: Nephrite could be used as a new additive component for CL storage cases and multipurpose solutions to improve the disinfection effects on Acanthamoeba.

Simultaneous Recording of Flash Electroretinography and Visual Evoked Potential in Vitreous Hemorrhage with Diabetic Retinopathy

PURPOSE: To determine whether the simultaneous recording of photopic electroretinography (ERG) and flash visual evoked potential (VEP) can predict the postoperative outcome in diabetic cases where massive vitreous hemorrhage precludes fundus observation. METHODS: The photopic ERG and flash VEP were recorded simultaneously on 20 eyes of 20 normal subjects, and 23 eyes of 23 patients who were diagnosed with Grade IV vitreous hemorrhage d/t diabetic retinopathy. Of the 23 patients, fellow eyes were diagnosed with proliferative diabetic retinopathy and they underwent pars plana vitrectomy after the test. Three groups were analyzed the responses of photopic ERG and flash VEP. Best corrected visual acuity was also checked before and after the surgery. After the 8 weeks after the vitrectomy, two groups were formed, based on the outcome of surgery and these two groups were analyzed the preoperative response of photopic ERG and flash VEP. RESULTS: When comparing the groups between proliferative diabetic retinopathy and normal eyes, Grade IV vitreous hemorrhage and fellow eyes, there was a statistically significant (p < 0.05) difference in a wave amplitude, a wave implicit time, b wave amplitude, b wave implicit time of photopic ERG and P2 peak time of flash VEP. In addition, a wave amplitude of photopic ERG showed the best predictive ability (area under receiver operating characteristic [AUROC] curve value of 0.88) when comparing improved visual acuity group to the unimproved visual acuity group. CONCLUSIONS: Simultaneous recordings of photopic ERG and flash VEP showed the decreased function of retina and optic pathway on eyes with vitreous hemorrhage precluding inspection of the fundus. In addition, preoperative photopic ERG and flash VEP can safely predict the outcome of vitrectomy in dense vitreous hemorrhage of diabetics.

Cerebrospinal Fluid Pressure and Trans-lamina Cribrosa Pressure Difference in Open-angle Glaucoma: KNHANES V

PURPOSE: To investigate the relationships between estimated cerebrospinal fluid pressure (CSFP) and trans-lamina cribrosa pressure difference (TLCPD) in open-angle glaucoma (OAG) in Korean population. METHODS: A total of 10,801 eyes were included from the Korean National Health and Nutrition Examination Survey V. All participants (aged 19 years or older) were classified as non-glaucomatous group, OAG suspect group and OAG group. CSFP was calculated as CSFP (mm Hg) = 0.44 body mass index (kg/m²) + 0.16 diastolic blood pressure (mm Hg) - 0.18 age (years) - 1.91. TLCPD was calculated by subtracting CSFP from intraocular pressure. RESULTS: The mean estimated CSFP was (8.7 ± 3.3 mm Hg vs. 11.6 ± 3.7 mm Hg, 11.2 ± 3.8 mm Hg vs. 11.6 ± 3.7 mm Hg) was lower, and the mean TLCPD (5.7 ± 4.4 mm Hg vs. 2.2 ± 4.4 mm Hg, 3 ± 4.7 mm Hg vs. 2.2 ± 4.4 mm Hg) was higher in the OAG group and in the OAG suspect group than in the non-glaucomatous control group, respectively (p < 0.001). After adjusting relating factor with CSFP and TLCPD using simple linear regression and multivariate analyses, the mean estimated CSFP was distributed lower (p < 0.001; beta: -0.12; B: -2.306; 95% confidence interval [CI]: -2.717, -1.895) in OAG group than in non-glaucomatous group and the mean TLCPD was distributed higher (p < 0.001; beta: 0.099; B: 1.349; 95% CI: 0.977, 1.72; p < 0.001; beta: 0.118; B: 2.776; 95% CI: 2.264, 3.289) in OAG suspect group and in OAG group than in non-glaucomatous group, respectively. CONCLUSIONS: Estimated CSFP and calculated TLCPD showed essential association with OAG presence. It supports the potential role of low CSFP in the pathogenesis of OAG.

Erratum: Multidetector CT Findings and Differential Diagnoses of Malignant Pleural Mesothelioma and Metastatic Pleural Diseases in Korea

On page 545, the fifth author's name has been incorrectly spelled as Jin Mo Koo. The correct spelling is Jin Mo Goo.

Multidetector CT Findings and Differential Diagnoses of Malignant Pleural Mesothelioma and Metastatic Pleural Diseases in Korea

OBJECTIVE: To compare the multidetector CT (MDCT) features of malignant pleural mesothelioma (MPM) and metastatic pleural disease (MPD). MATERIALS AND METHODS: The authors reviewed the MDCT images of 167 patients, 103 patients with MPM and 64 patients with MPD. All 167 cases were pathologically confirmed by sonography-guided needle biopsy of pleura, thoracoscopic pleural biopsy, or open thoracotomy. CT features were evaluated with respect to pleural effusion, pleural thickening, invasion of other organs, lung abnormality, lymphadenopathy, mediastinal shifting, thoracic volume decrease, asbestosis, and the presence of pleural plaque. RESULTS: Pleural thickening was the most common CT finding in MPM (96.1%) and MPD (93.8%). Circumferential pleural thickening (31.1% vs. 10.9%, odds ratio [OR] 3.670), thickening of fissural pleura (83.5% vs. 67.2%, OR 2.471), thickening of diaphragmatic pleura (90.3% vs. 73.4%, OR 3.364), pleural mass (38.8% vs. 23.4%, OR 2.074), pericardial involvement (56.3% vs. 20.3%, OR 5.056), and pleural plaque (66.0% vs. 21.9%, OR 6.939) were more frequently seen in MPM than in MPD. On the other hand, nodular pleural thickening (59.2% vs. 76.6%, OR 0.445), hilar lymph node metastasis (5.8% vs. 20.3%, OR 0.243), mediastinal lymph node metastasis (10.7% vs. 37.5%, OR 0.199), and hematogenous lung metastasis (9.7% vs. 29.2%, OR 0.261) were less frequent in MPM than in MPD. When we analyzed MPD from extrathoracic malignancy (EMPD) separately and compared them to MPM, circumferential pleural thickening, thickening of interlobar fissure, pericardial involvement and presence of pleural plaque were significant findings indicating MPM than EMPD. MPM had significantly lower occurrence of hematogenous lung metastasis, as compared with EMPD. CONCLUSION: Awareness of frequent and infrequent CT findings could aid in distinguishing MPM from MPD.

Comparisons of Bleeding Risks between Rivaroxaban and Dalteparin for Treatment of Venous Thromboembolism in Cancer Patients

BACKGROUND: Venous thromboembolism (VTE) is a common and life-threating condition in cancer patients. Low molecular weight heparins (LMWH), such as dalteparin, are recommended in the treatment of VTE. Also, rivaroxaban, an orally administered direct factor Xa inhibitor, was approved for the treatment of VTE. It showed similar efficacy to standard therapy (LMWH or warfarin) and was associated with significantly lower rates of major bleedings. However, in the real world, bleeding has been reported to occur frequently in cancer patient receiving rivaroxaban. The goal of this research was to analyze bleeding risks between rivaroxaban and dalteparin for treatment of VTE in cancer patients. METHODS: Medical records of oncology patients who were treated with rivaroxaban or dalteparin for VTE from July 2012 to June 2014 were retrospectively reviewed. Data collected were as follows: age, sex, weight, height, cancer types and stages, ECOG (eastern cooperative oncology group) PS (performance score), VTE types, concurrently used medications, study drug information (dose and duration of therapy), INR (international normalized ratio), PT (prothrombin time), and platelet counts. Bleeding was classified into major bleedings, clinically relevant non-major bleedings, and minor bleedings. RESULTS: A total of 399 patients were included in the study. Of these patients, 246 were treated with rivaroxaban and 153 with dalteparin. Bleeding rates were significantly higher in the rivaroxaban group than in the dalteparin group (adjusted odds ratio (AOR) 2.09, 95% CI 1.22-3.60) after adjusting for confounders. In addition, rivaroxaban remained independently associated with 1.78-fold (95% CI 1.14-2.76) shorter time to bleeding compared to dalteparin after adjusting other factors known to be associated with poor outcomes. CONCLUSION: This study suggested that rivaroxaban was associated with an increased risk of bleedings in cancer patients.

Radiologic Diagnosis of Asbestosis in Korea

Asbestosis is the most important change noted in the lung parenchyma after environmental and occupational exposure to asbestos fibers. It is characterized by diffuse interstitial pulmonary fibrosis. In Korea, the incidence of asbestosis will continue to increase for many years to come and the government enacted the Asbestos Damage Relief Law in 2011 to provide compensation to those suffering from asbestos-related diseases. Radiologic evaluation is necessary for diagnosis of asbestosis, and radiologists play a key role in this process. Therefore, it is important for radiologists to be aware of the various imaging features of asbestosis.

CT Characteristics of Pleural Plaques Related to Occupational or Environmental Asbestos Exposure from South Korean Asbestos Mines

OBJECTIVE: This study evaluated the CT characteristics of pleural plaques in asbestos-exposed individuals and compared occupational versus environmental exposure groups. MATERIALS AND METHODS: This study enrolled 181 subjects with occupational exposure and 98 with environmental exposure from chrysotile asbestos mines, who had pleural plaques confirmed by a chest CT. The CT scans were analyzed for morphological characteristics, the number and distribution of pleural plaques and combined pulmonary fibrosis. Furthermore, the CT findings were compared between the occupational and environmental exposure groups. RESULTS: Concerning the 279 subjects, the pleural plaques were single in 2.2% and unilateral in 3.6%, and showed variable widths (range, 1-20 mm; mean, 5.4 +/- 2.7 mm) and lengths (5-310 mm; 72.6 +/- 54.8 mm). The chest wall was the most commonly involved (98.6%), with an upper predominance on the ventral side (upper, 77.8% vs. lower, 55.9%, p < 0.001) and a lower predominance on the dorsal side (upper, 74.9% vs. lower, 91.8%, p = 0.02). Diaphragmatic involvement (78.1%) showed a right-side predominance (right, 73.8% vs. left, 55.6%, p < 0.001), whereas mediastinal plaques (42.7%) were more frequent on the left (right, 17.6% vs. left, 39.4%, p < 0.001). The extent and maximum length of plaques, and presence and severity of combined asbestosis, were significantly higher in the occupational exposure group (p < 0.05). CONCLUSION: Pleural plaques in asbestos-exposed individuals are variable in number and size; and show a predominant distribution in the upper ventral and lower dorsal chest walls, right diaphragm, and left mediastinum. Asbestos mine workers have a higher extent of plaques and pulmonary fibrosis versus environmentally exposed individuals.

Effect of Dominant Eye and Contextual Background on Binocular Rivalry

PURPOSE: We investigated the effects of dominant eye and contextual background on predominance during binocular rivalry. METHODS: 10 subjects were recruited for the present study. Dominant eye was determined using the hole-in-the-card test. In experiment 1, subjects viewed the stimuli through anaglyph filters and reported the predominance of color. The subject's responses were compared with the color on the dominant eye. To investigate the influence of color dominance and contextual color, we conducted the experiment with added contextual color information target through switched-anaglyph filters. In experiment 2, the subject viewed the stimuli through the polarized filters and reported the predominance of orientation. The subject's responses were compared with the grating on dominant eye. To rule out the effect of stimulus size, we conducted the experiment with a smaller target. We designed the additional experiment to investigate the influence of contextual grating information on binocular rivalry. RESULTS: 10 subjects were evaluated. In experiment 1, 8 of 10 subjects reported that eye preference was highly correlated with dominant eye. This finding is significant without reference to color. In experiment 2, 7 of 10 subjects reported that eye preference was highly correlated with dominant eye. This finding is significant without reference to size. In experiment 1-2 and 2-2, all subjects reported that predominance of context contradictory target increased. CONCLUSIONS: We found the relationship between the dominant eye and eye preference. Experiment 1-2 and 2-2 showed that contradictory contextual information increases target predominance during binocular rivalry. Overall, our results indicate that the contextual background reduce the stimulus strength of the context-congruent target; it would correspond to an increase in the dominance duration of the context-contradictory target.

Spectral-Domain Optical Coherence Tomography Findings of Vogt-Koyanagi-Harada Disease

PURPOSE: To report characteristics of Vogt-Koyanagi-Harada (VKH) disease as observed on spectral-domain optical coherence tomography (SD-OCT) images. CASE SUMMARY: (Case 1) A 38-year-old female presented with visual impairment in both eyes. On fundus examination, multifocal serous retinal detachment in the posterior pole was observed in both eyes. On enhanced SD-OCT, serous retinal detachment and cystoid macular edema in the outer retina were observed and the intraretinal fluid space was divided by a membranous structure forming an intraretinal compartmentalized cystic space. Under the diagnosis of VKH disease, the patient was treated with intravenous administration of methylprednisolone. After treatment, enhanced SD-OCT images showed decreased serous retinal detachment. (Case 2) A 58-year-old male presented with visual impairment in both eyes. On fundus examination, multifocal serous retinal detachment in the posterior pole was observed in both eyes. On enhanced SD-OCT, choroidal folds were observed and the membranous structure showed continuity with ellipsoid zone, suggesting the membranous structure was part of the outer photoreceptor layer of the adjacent attached retina. The patient was treated with intravenous administration of methylprednisolone. After treatment, enhanced SD-OCT images showed cystic space was decreased. CONCLUSIONS: SD-OCT images of VKH disease demonstrated multiple serous retinal detachments and intraretinal compartmentalized cystic space divided by a membranous structure. The membranous structure may be considered a part of the outer photoreceptor layer of the attached retina.

Annual Change in Pulmonary Function and Clinical Characteristics of Combined Pulmonary Fibrosis and Emphysema and Idiopathic Pulmonary Fibrosis: Over a 3-Year Follow-up / 결핵및호흡기질환

BACKGROUND: Combined pulmonary fibrosis and emphysema (CPFE) have different pulmonary function tests (PFTs) and outcomes than idiopathic pulmonary fibrosis (IPF). The intention of this study was to identify unknown differences between CPFE and IPF by a retrospective comparison of clinical data including baseline and annual changes in pulmonary function, comorbidities, laboratory findings, clinical characteristics and cause of hospitalization. METHODS: This study retrospectively enrolled patients with CPFE and IPF who had undergone PFTs once or several times per year during a follow-up period of three years. Baseline clinical characteristics and the annual changes in the pulmonary function during the follow-up period were compared between 26 with CPFE and 42 patients with IPF. RESULTS: The baseline ratio of forced expiratory volume in one second to forced vital capacity (FEV1/FVC%) in patients with CPFE was lower than that in patients with IPF (78.6+/-1.7 vs. 82.9+/-1.1, p=0.041). The annual decrease in FEV1/FVC in the CPFE was significantly higher than in the IPF. The annual decreases in diffusion capacity of carbon monoxide and FVC showed no significant differences between the two groups. The symptom durations of cough and sputum were in the CPFE significantly lower than in the IPF. The serum erythrocyte sedimentation rate level at the acute stage was significantly higher than in the IPF. There were no significant differences in the hospitalization rate and pneumonia was the most common cause of hospitalization in both study groups. CONCLUSION: The annual decrease of FEV1/FVC was in patients with CPFE significantly higher than in the patients with IPF.

Annual Change in Pulmonary Function and Clinical Characteristics of Combined Pulmonary Fibrosis and Emphysema and Idiopathic Pulmonary Fibrosis: Over a 3-Year Follow-up / 결핵및호흡기질환

BACKGROUND: Combined pulmonary fibrosis and emphysema (CPFE) have different pulmonary function tests (PFTs) and outcomes than idiopathic pulmonary fibrosis (IPF). The intention of this study was to identify unknown differences between CPFE and IPF by a retrospective comparison of clinical data including baseline and annual changes in pulmonary function, comorbidities, laboratory findings, clinical characteristics and cause of hospitalization. METHODS: This study retrospectively enrolled patients with CPFE and IPF who had undergone PFTs once or several times per year during a follow-up period of three years. Baseline clinical characteristics and the annual changes in the pulmonary function during the follow-up period were compared between 26 with CPFE and 42 patients with IPF. RESULTS: The baseline ratio of forced expiratory volume in one second to forced vital capacity (FEV1/FVC%) in patients with CPFE was lower than that in patients with IPF (78.6+/-1.7 vs. 82.9+/-1.1, p=0.041). The annual decrease in FEV1/FVC in the CPFE was significantly higher than in the IPF. The annual decreases in diffusion capacity of carbon monoxide and FVC showed no significant differences between the two groups. The symptom durations of cough and sputum were in the CPFE significantly lower than in the IPF. The serum erythrocyte sedimentation rate level at the acute stage was significantly higher than in the IPF. There were no significant differences in the hospitalization rate and pneumonia was the most common cause of hospitalization in both study groups. CONCLUSION: The annual decrease of FEV1/FVC was in patients with CPFE significantly higher than in the patients with IPF.