Byung Hak Rho

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.

Male predominance of pneumonia and hospitalization in pandemic influenza A (H1N1) 2009 infection

BackgroundPandemic influenza A (H1N1) disproportionately affects different age groups. The purpose of the current study was to describe the age and gender difference of pandemic influenza A (H1N1) cases that lead to pneumonia, hospitalization or ICU admission.MethodsData were collected retrospectively between May 2009 and December 2009. All of the diagnoses of H1N1 were confirmed by real-time reverse-transcription polymerase chain reaction (RT-PCR).ResultsDuring the study period there were 3402 cases of RT-PCR positive H1N1, among which 1812 were males and 1626 were adults (> 15 years of age). 6% (206/3402) of patients required hospitalization, 3.6% (122/3402) had infiltrates on chest radiographs, and 0.70% (24/3402) were admitted to intensive care unit (ICU). The overall fatality rate was 0.1% (4/3402). The rate of hospitalization was sharply increased in patients ≥ 50 years of age especially in male. Out of 122 pneumonia patients, 68.8% (84 patients) were male. Among the patients admitted to the ICU, 70.8% (17 patients) were male. Approximately 1 of 10 H1N1-infected patients admitted to the ICU were ≥ 70 years of age.ConclusionsAmong the confirmed cases of H1N1, the ICU admission rate was < 1% and the case fatality rate was 0.1%. Male had a significantly higher rate of pneumonia and hospital admission. These findings should be taken into consideration when developing vaccination and treatment strategies.

Hürthle cell neoplasm: correlation of gray-scale and power Doppler sonographic findings with gross pathology.

To describe gray‐scale and power Doppler (PD) sonographic (US) findings of Hürthle cell neoplasms (HCNs) of the thyroid gland, and to determine if there is any correlation between US and gross pathologic features.

Estimated incidence of acute pulmonary embolism in a Korean hospital.

Patients with acute pulmonary embolism (PE) were identified retrospectively from patients hospitalized during a 2-year period from 2005 to 2007. Among adult patients (≥20 years), the incidence of established acute PE was 88 (0.17%) of 50 882 in Dongsan Hospital. The incidence of acute PE at Dongsan Hospital was 26% lower than that at Henry Ford Hospital (P < .01). Among patients more than 50 years of age, PE was more frequent in women (0.32%; 95% CI, 0.24-0.4) than in men (0.15%; 95% CI, 0.1-0.21; P < .01). Among all patients with PE older than 20 years of age, 68 (0.21%) of 31 869 (95% CI, 0.17-0.26) were from the medical service and 18 (0.08%) of 23 139 (95% CI, 0.04-0.11; P < .01) were from the surgical service. The estimated incidence of PE in a university teaching hospital in Korea was 0.17%, it was about two thirds of that in North America.

Myopericytoma of the neck: sonographic appearance and sonographically guided needle biopsy.

We report the imaging and pathologic findings of a case of myopericytoma of the neck in a 70‐year‐old woman, which was diagnosed by ultrasound‐guided core‐needle biopsy. The mass demonstrated homogeneous intense enhancement on contrast‐enhanced CT and was markedly hypervascular on power Doppler sonography. The histopathological findings of the core biopsy were consistent with myopericytoma.

Acute respiratory distress due to methane inhalation.

Inhalation of toxic gases can lead to pneumonitis. It has been known that methane gas intoxication causes loss of consciousness or asphyxia. There is, however, a paucity of information about acute pulmonary toxicity from methane gas inhalation. A 21-year-old man was presented with respiratory distress after an accidental exposure to methane gas for one minute. He came in with a drowsy mentality and hypoxemia. Mechanical ventilation was applied immediately. The patients symptoms and chest radiographic findings were consistent with acute pneumonitis. He recovered spontaneously and was discharged after 5 days without other specific treatment. His pulmonary function test, 4 days after methane gas exposure, revealed a restrictive ventilatory defect. In conclusion, acute pulmonary injury can occur with a restrictive ventilator defect after a short exposure to methane gas. The lung injury was spontaneously resolved without any significant sequela.

Follicular thyroid adenoma with eggshell calcification presenting as an intensely hypermetabolic lesion on 18F‐FDG PET/CT

We report herein a case of follicular thyroid adenoma with an eggshell calcification presenting as an intensely hypermetabolic lesion on combined 18F‐fluorodeoxyglucose whole‐body PET and CT (18F‐FDG PET/CT) performed for staging work‐up in a 68‐year‐old woman who had undergone distal gastrectomy with Billroth II anastomosis for early gastric carcinoma. The mass was intensely hypermetabolic (SUVmax = 21.3 g/mL) on combined 18F‐FDG PET/CT, hypoechoic with an interrupted eggshell calcification on gray‐scale ultrasonography (US), and showed intranodular vascularity on power Doppler US. Follicular adenoma should be considered in the differential diagnosis of a mass with an eggshell calcification on US and intense hypermetabolism on 18F‐FDG PET/CT.

Isolated Cervical Lymph Node Sarcoidosis Presenting in an Asymptomatic Neck Mass: A Case Report

Sarcoidosis, a systemic granulomatous disease of unknown etiology. The presentation of sarcoidal granuloma in neck nodes without typical manifestations of systemic sarcoidosis is difficult to diagnose. We describe the case of a 37-year-old woman with an increasing mass on the right side of neck. The excisional biopsy from the neck mass showed noncaseating epithelioid cell granuloma of the lymph nodes. No evidence of mycobacterial or fungal infection was noted. Thoracic evaluations did not show enlargement of mediastinal lymph nodes or parenchymal abnormalities. Immunohistochemistry showed abundant expression of tumor necrosis factor-α in the granuloma. However, transforming growth factor-β was not expressed, although interleukin-1β was focally expressed. These immunohistochemical findings supported characterization of the granuloma and the diagnosis of sarcoidosis. Sarcoidosis can present with cervical lymph node enlargement without mediastinal or lung abnormality. Immunohistochemistry may support the diagnosis of sarcoidosis and characterization of granuloma.

Small Airway-Centered Granulomatosis Caused by Long-term Exposure to Polytetrafluoroethylene

To date, there have been no reports of chronic pulmonary granulomatosis associated with exposure to polytetrafluoroethylene (PTFE). Here, we report three cases of small airway-centered granulomatous lesions in workers employed at facilities that apply coatings to pans and other utensils. The workers were repeatedly exposed to PTFE particles that were probably generated by the drying process when PTFE coatings are dried in a convection oven at high temperatures (380-420 °C). The duration of inhalational PTFE exposure was between 7 and 20 years. We found granulomatous lung lesions around the small airways in lung biopsy specimens obtained from the workers. Scanning electron microscopy/energy-dispersive x-ray spectroscopy analysis was performed focusing on areas where the PTFE particles were suspected to be located in macrophages. The scanning electron microscopy/energy-dispersive x-ray spectroscopy analyses revealed fluorine in the particles. Lung tissue samples from all cases were analyzed using a fully automated Fourier transform infrared spectrometer. Analysis of the spectrum extracted from the position of the foreign particles enabled precise identification of the foreign bodies as PTFE. Fourier transform infrared revealed that all of the lung tissue samples had bands at 1,202 to 1,148 cm(-1) and 1,202 to 1,146 cm(-1), which are characteristic of the asymmetric and symmetric stretching vibrations of the C-F bonds of PTFE. These cases suggest that recurrent inhalational exposure to PTFE particles causes chronic pulmonary granulomatosis.