Clinical and imaging characteristics of 108 lung isolated ground-glass opacity / 中国医师杂志

Objective To investigate the clinical and computed tomography (CT) features of lung isolated ground-glass opaci-ty and to analyze the predictive factors that may discriminate benign from malignant nodules .Methods Clinical features , CT charac-teristics, pathological diagnosis , and the follow-up results were retrospectively analyzed with 108 cases of isolated ground-grass opacity (GGO) that was confirmed by histopathology from January 2011 to March 2013.Results A total of 108 isolated GGOs [52 men,56 women,mean age (58.12 ±10.34)years] included 19 benign nodules and 89 malignant nodules.The diversity of age, gender, clini-cal symptom, margin (speculation, spine-like process), internal characteristics (ovule sign, air bronchograms) of the lesions were no statistically significant differences between benign and malignant GGOs ( P >0.05 ) .The lymphocyte and CT findings of shape , lobu-lation, interface (ill/well defined) and pleural indentation sign were significantly different between benign and malignant GGOs ( P <0.05 ) .Besides significant difference in pleural indentation sign was also found between bronchioalveolar carcinoma and adenocarcino -ma ( P =0.0252).Among the 44 patients who were followed up after finding GGO initially , there were 7 GGOs (7/44,15.91%) to grow up after 3years, and GGOs of 32 patients had no obvious change , besides the patients'age of malignant GGO was bigger than the benign( P =0.0416).Conclusions Clinical features were of little value to discriminate the benign from malignant GGOs .CT fea-tures including round/oval shape, lobulation, and well defined and pleural indentation sign were of important value in the diagnosis of malignant GGO .Surgical resection should be applied in the process of follow-up when the sizes of GGO become bigger or newly formed solid components were detected .GGO that can't be diagnosed should be followed up for at least 3 years.

Atelectasia pulmonar em recém-nascidos: etiologia easpectos radiológicos / Pulmonary atelectasis in newborn infants: etiology and radiological aspects

Objetivos: Descrever os principais fatores etiológicos e os achados radiológicos da atelectasia pulmonar em recémnascidos. Fonte de dados: Foi realizada uma revisão da literatura através de livros e artigos publicados nos últimos 30 anos, obtidos a partir das bases de dados PubMed, SciELO e BIREME, utilizando-se os descritores: atelectasia pulmonar/pulmonary atelectasis, diagnóstico/diagnosis, neonato/neonate, recém-nascido/infant, newborn.Síntese dos dados: Os sinais radiológicos de atelectasia pulmonar estão relacionados à perda volumétrica, com deslocamento cissural, hilar e mediastinal, bem como elevação diafragmática em direção ao lobo ou segmento pulmonar afetado. Os arcos costais no hemitórax comprometido podem apresentar espaços reduzidos. Está presente hiperinsuflação compensatória do pulmão remanescente e as porções colapsadas apresentam aumento da radiopacidade com forma triangular em pelo menos uma das projeções radiológicas. Em recém-nascidos, os principais fatores etiológicos são ventilação pulmonar mecânica com pressão positiva, pneumonia, síndrome da aspiração de mecônio, refluxo gastroesofágico, displasia broncopulmonar, hérnia diafragmática congênita, derrame pleural e pneumotórax.Conclusões: A presença de atelectasia pulmonar é uma importante complicação em recém-nascidos internados em unidade de terapia intensiva neonatal. O exame radiológico possui um importante papel no diagnóstico e no direcionamento do tratamento desses pacientes.

Aims: To describe the main risk factors and the radiological findings of pulmonary atelectasis in newborns.Source of data: A literature review was conducted for the period of 2010/2011, through books and articles published over the past 30 years, obtained from the databases PubMed, SciELO and BIREME, using the descriptors: pulmonary atelectasis, diagnosis, infant, neonate, newborn.Summary of findings: Radiological signs of pulmonary atelectasis are related to volume loss, with fissural, hilar and mediastinal displacement, and diaphragmatic elevation toward the affected lung lobe or segment. The ribs of the affectedhemithorax may have diminished spaces. Compensatory hyperinflation of the lung is present and the collapsed portionsshow increased radiopacity, with a triangular shape in at least one of radiographic projections. In newborn infants, the main etiological factors are mechanical ventilation with positive pressure, pneumonia, meconium aspiration syndrome, gastroesophageal reflux, bronchopulmonary dysplasia, congenital diaphragmatic hernia, pleural effusion and pneumothorax.Conclusions: Presence of pulmonary atelectasis is an important complication in infants admitted to neonatal intensive care unit. Radiology has an important role in the diagnosis and management of these patients.

Pulmonary Complication of Novel Influenza A (H1N1) Infection: Imaging Features in Two Patients

Novel influenza A (H1N1) virus is the pathogen of recent global outbreaks of febrile respiratory infection. We herein report the imaging findings of pulmonary complication in two patients with novel influenza A (H1N1) infection. The first patient without secondary infection showed the ill-defined ground-glass opacity nodules and patch areas of ground-glass opacities. The second patient with secondary pneumococcal pneumonia showed areas of lobar consolidation in the right middle lobe and left lower lobe and ground-glass opacities.

A Correlation between the Severity of Lung Lesions on Radiographs and Clinical Findings in Patients with Severe Acute Respiratory Syndrome

OBJECTIVE: The purpose of this study was to quantify lesions on chest radiographs in patients with severe acute respiratory syndrome (SARS) and analyze the severity of the lesions with clinical parameters. MATERIALS AND METHODS: Two experienced radiologists reviewed chest radiographs of 28 patients with SARS. Each lung was divided into upper, middle, and lower zones. A SARS-related lesion in each zone was scored using a four-point scale: zero to three. The mean and maximal radiographic scores were analyzed statistically to determine if the scorings were related to the laboratory data and clinical course. RESULTS: Forward stepwise multiple linear regression showed that the mean radiographic score correlated most significantly with the number of hospitalized days (p < 0.001). The second most significant factor was the absolute lymphocyte count (p < 0.001) and the third most significant factor was the number of days of intubation (p = 0.025). The maximal radiographic score correlated best with the percentage of lymphocytes in a leukocyte count (p < 0.001), while the second most significant factor was the number of hospitalized days (p < 0.001) and the third most significant factor was the absolute lymphocyte count (p = 0.013). The mean radiographic scores of the patients who died, with comorbidities and without a comorbidity were 11.1, 6.3 and 2.9, respectively (p = 0.032). The corresponding value for maximal radiographic scores were 17.7, 9.7 and 6.0, respectively (p = 0.033). CONCLUSION: The severity of abnormalities quantified on chest radiographs in patients with SARS correlates with the clinical parameters.

Bronchial Asthma: Correlation of Quantitative CT and the Pulmonary Function Test

PURPOSE: The purpose of this study was to assess the availability of quantitative computed tomography (QCT) in the evaluation of asthma patients and to correlate its use with the pulmonary function test (PFT). MATERIALS AND METHODS: Thirty asthmatic patients and thirty normal volunteers were prospectively evaluated by the use of HRCT and the PFT. By using 16 slice MDCT, HRCT was performed from the apex to the base of both lungs at the end inspiration and end expiration periods in all patients and images were reconstructed to a thickness of 1 mm (window level: -750 HU, window width: 1,500 HU). We analyzed each image for the whole lung using the Pulmo CT program. PFTs including FVC and FEV1 were performed one week prior and one week after the completion of a HRCT. The Difference of QCT (the mean lung density and subrange ratio) between volunteers and asthmatic patients was analyzed by using the Student's t-test. Spearman's correlation test was used to determine the association between PFT and QCT. RESULTS: The mean lung density (MLD) and subrange ratio were lower in asthmatic patients than in volunteers for end expiration and no difference was seen between asthmatic patients and volunteers for end inspiration. FVC and FEV1 were lower in asthmatic patients than in volunteers. A decrease in FVC and FEV1 correlated with changes in the MLD and subrange ratio for end expiration. CONCLUSION: QCT such as MLD and the subrange ratio using HRCT can be used to indirectly assess the pulmonary function of the asthma patient. The PFT seems to correlate better with the MLD and subrange ratio for expiratory QCT of the asthma patient than with inspiratory QCT.

Radiologic Approach to Diffuse Infiltrative Lung Disease

The Radiology approach to diffuse infiltrative lung disease (DILD) is based on a chest radiography and CT. Chest radiography can categorize DILD into five main patterns of abnormality: linear, reticular, cystic, nodular, and ground-glass patterns. The CT patterns of DILD can be classified into six patterns including thickened interlobular septa, reticular, cystic, nodular, ground-glass, and consolidation patterns. The pertinent differential diagnosis of DILD is based on the pattern recognition approach of abnormalities, and a specific diagnosis can often be made using chest radiography and CT. This pictorial essay illustrates the radiology pattern recognition approach for DILD using chest radiography and CT.

Severe Sand Aspiration: A Case Report

We report here on a case of sand aspiration in a 32-year-old man who had been accidentally buried in the deep pile of sand for four hours. Chest radiograph showed bilateral fluffy consolidations and nodular lesions with a typical 'sand bronchogram' in both lower lung zones, and these findings were more clearly visualized on the HRCT. The patient recovered completely with conservative treatment that included mechanical ventilation and postural drainage.

Three-year Follow-up of Niemann-Pick Disease with Pulmonary Involvement: A Case Report

Niemann-Pick disease is a rare inherited metabolic storage disease that causes excessive intracellular storage of sphingomyelin in various organs. We present the pulmonary imaging findings with particular emphasis on the CT findings in a case of Niemann-Pick disease type B with pulmonary involvement. The chest radiograph showed fine reticulonodular opacities in both basal lung fields, and the high-resolution chest CT showed centrilobular nodular opacities and smooth thickening of the interlobar fissure and interlobular septum with a basal lung predominance. Coronal reformatted CT revealed a prominent interlobular septal thickening around the diaphragm. The follow-up high-resolution chest CT showed no significant interval changes over a 3-years period.

Radiographic Manifestations of Reperfusion Edema after Transplantation

PURPOSE: To elucidate the sequential radiologic manifestations of reperfusion edema after lung transplantation. MATERIALS AND METHODS: The study group comprised five consecutive lung transplant recipients (M:F=3:2; mean age; 47.5 years) who between July 1996 and April 2002 underwent lung transplantation procedures (four, unilateral; one, bilateral) at our institution. We retrospectively reviewed the serial postoperative radiographs obtained and characterized the lung infiltrates. RESULTS: Lung infiltrates compatible with reperfusion edema were present in all patients (5/5). Reperfusion edema appeared on day 1 in four, and by day 2 in the other. In all transplanted lungs, infiltrates were found in the perihilar and basilar regions, and were scored as maximal on day 1 in one, day 3 in two, day 4 in one and day 5 in the other. CONCLUSION: The recognition of sequential radiological manifestations helps identify recognition of reperfusion edema after lung transplantation.

Pulmonary Complications in Major Burn Patients: Differences in Radiologic and Clinical Findings between Inhaled and Non-inhaled Burn

PURPOSE: To analyze differences in the radiologic and clinical findings of pulmonary complications between an inhalation and non-inhalation group of major burn patients, and to apply the findings to the specific diagnosis of pulmonary complications. MATERIALS AND METHODS: This study involved 45 major burn patients (18 with inhalation injury, and 27 without) in whom pulmonary complications ensued. Follow-up studies were based on chest radiographs obtained between initial burn day and postburn (PB) 57 (mean, day 27). Types, times of onset, underlying causes, and changes at follow-up study of pulmonary complications between the inhalation and the non-inhalation group were assessed. RESULTS: In the inhalation group, the most frequent complication was air-borne pneumonia (n=7, 39%); others were hydrostatic pulmonary edema (n=5, 28%), ARDS (n=5, 28%), atelectasis (n=5, 28%), inhalation pneumonitis (n=3, 17%), pleural effusion (n=3, 17%), and hematogenous pneumonia (n=1, 6%). In the non-inhalation group, airborne pneumonia (n=8, 30%) was also the most common complication; other were hydrostatic edema (n=6, 22%), ARDS (n=5, 19%), atelectasis (n=5, 19%), pleural effusion (n=5, 19%) and hematogenous pneumonia (n=2, 7%). The average times of onset were as follow: for airborne pneumonia, PB day 13.1 (range, 5-27) in the inhalation group, and PB day 21.7 (10-49) in the non-inhalation group; for hematogenous pneumonia, more than one month, regardless of inhalation; for ARDS, PB day 4.9 (2-15) and PB day 13 (7-20) in the inhalation and non-inhalation group, respectively; and for inhalation pneumonitis, PB day 1.7 (1-3). The most common probable cause of ARDS in the inhalation group was inhalation injury (3/5), and in the noninhalation group, sepsis (4/5). CONCLUSION: In major burn patients, pulnonary complications differed in terms of their onset time and causes between the inhalation group and the non-inhalation group. In such cases, awareness of the presence or absence of inhalation injury and the onset time of pulmonary complications is necessary if complications are to be specifically diagnosed.

Superficial Endobronchial Lung Cancer: Radiologic-Pathologic Correlation

OBJECTIVE: To analyze the plain chest radiographic and CT findings of superficial endobronchial lung cancer and to correlate these with the findings of histopathology. MATERIALS AND METHODS: This study involved 19 consecutive patients with pathologically proven lung cancer confined to the bronchial wall. Chest radiographs and CT scans were reviewed for the presence of parenchymal abnormalities, endobronchial nodules, bronchial obstruction, and bronchial wall thickening and stenosis. The CT and histopathologic findings were compared. RESULTS: Sixteen of the 19 patients had abnormal chest radiographic findings, while in 15 (79%), CT revealed bronchial abnormalities: an endobronchial nodule in seven, bronchial obstruction in five, and bronchial wall thickening and stenosis in three. Histopathologically, the lesions appeared as endobronchial nodules in 11 patients, irregular thickening of the bronchial wall in six, elevated mucosa in one, and carcinoma in situ in one. CONCLUSION: CT helps detect superficial endobronchial lung cancer in 79% of these patients, though there is some disagreement between the CT findings and the pathologic pattern of bronchial lesions. Although nonspecific, findings of bronchial obstruction or bronchial wall thickening and stenosis should not be overlooked, and if clinically necessary, bronchoscopy should be performed.

Unilateral Hyperlucency of the Lung: A Systematic Approach to Accurate Radiographic Interpretation

The radiographic appearance of a unilateral hyperlucent lung is related to various conditions, the accurate radiographic interpretation of which requires a structured approach as well as an awareness of the spectrum of these entities. Firstly, it is important to determine whether a hyperlucent hemithorax is associated with artifacts resulting from rotation of the patient, grid cutoff, or the heel effect. The second step is to determine whether or not a hyperlucent lung is abnormal. Lung that is in fact normal may appear hyperlucent because of diffusely increased opacity of the opposite hemithorax. Thirdly, thoracic wall and soft tissue abnormalities such as mastectomy or Poland syndrome may cause hyperlucency. Lastly, abnormalities of lung parenchyma may result in hyperlucency. Lung abnormalities can be divided into two groups: a) obstructive or compensatory hyperinflation; and b) reduced vascular perfusion of the lung due to congenital or acquired vascular abnormalities. In this article, we describe and illustrate the imaging spectrum of these causes and outline a structured approach to accurate radiographic interpretation.

Radiographic Findings of Miliary Tuberculosis: Difference in Patients with and those without Associated Acute Respiratory Failure

Purpose: To determine the differences in the radiographic findings of miliary tuberculosis between patients with and without associated acute respiratory failure (ARF). MATERIALS AND METHODS: We retrospectively reviewed 32 patients in whom miliary tuberculosis had been diagnosed, and assigned them to one of two groups: with ARF (n=10), and without ARF (n=22). Chest radiographic findings such as the presence of miliary nodules, cosolidation, ground-glass opacity (GGO), pleural effusion, small calcified nodules and linear opacities were assessed, the size and profusion of nodules in each of four zones were analyzed and scored using the standard radiographs of the International Labor Organization, and the extent of consolidation and GGO were scored according to the percentage of involved lung. We compared the radiologic findings between the two groups. RESULTS: Ground-glass opacity, consolidation, and pleural effusion were seen more frequently in miliary tuberculosis patients with ARF than in those without ARF. Although the size and profusion of nodules were similar in both groups (p>0.05), consolidation and ground-glass opacity in cases of miliary tuberculosis with ARF were significantly more extensive than in those without ARF (p<0.005). CONCLUSION: GGO and consolidation were more extensive in miliary tuberculosis patients with ARF. A finding of ground-glass opacity in miliary tuberculosis patients might be an early indication of developing ARF.

Nonbronchial Systemic Feeding Arteries in Patients with Hemoptysis: Predictive Factors at Radiography

PURPOSE: To determine the radiographic findings which predict the presence of nonbronchial systemic feeding arteries (NBFAs) in patients undergoing embolotherapy to control hemoptysis. MATERIALS AND METHODS: In 48 patients (39 men and 9 women; mean age, 51 years) who underwent embolotherapeutic procedures for controlling hemoptysis, selective angiography was performed at the intercostal, subclavian and bronchial arteries in 65 hemithoraces (right 11, left 20, bilateral 17). Underlying diseases were tuberculosis (n=34, including three patients with aspergilloma), bronchiectasis (n=11), paragonimiasis(n=2) and metastatic cancer (n=1). The presence of NBFA at angiography was correlated with radiographic findings including pleural thickening, parenchymal distortion, and the location of lung lesions. RESULTS: NBFAs were found in 34 (77%) of 44 hemithoraces with pleural thickening, and in six (29%) of 21 without pleural thickening; the sensitivity and specificity of prediction were 85% and 60%, respectively. NBFAs were observed with greater frequency as the thickness of the pleura increased, and the extent of pleural thickening correlated less with the presence of NBFA than did thickness. NBFAs were found in 35 (78%) of 45 hemithoraces with parenchymal distortion, and in five (25%) of 20 without distortion (p<0.001). In addition, the distribution of the underlying disease in the upper lung zone showed close correlation with the presence of NBFAs (p<0.05). CONCLUSION: In patients with hemoptysis, the pleural thickening revealed by radiography has a high sensitivity and a relatively low specificity for predicting the presence of NBFA, and patients with parenchymal distortion and upper lung lesions have a high incidence of NBFA.

ATRA (all-trans-retinoic acid) Syndrome in Acute Promyelocytic Leukemia: Clinical and Radiologic Findings

PURPOSE: To describe the clinical and radiologic findings of all-trans-retinoic acid (ATRA) syndrome in acute promyelocytic leukemia. MATERIALS AND METHODS: Among 21 patients with acute promyelocytic leukemia who were treated with all-trans- retinoic acid between 1995 and 1998, we retrospectively evaluated the cases of four with ATRA syn-drome. Two were male and two were female, and their mean age was 58 years. The clinical and radiologic findings of chest radiography (n=4) and HRCT (n=1) were analyzed. RESULTS: Between seven and 13 days after ATRA treatment, dry cough, dyspnea and high fever developed in all patients. The WBC count in peripheral blood was significantly higher [2.9 -25.3(mean, 10.8)-fold] than before ATRA treatment, and in all patients, chest radiography revealed ill-defined consolidation and pleural effu-sion. Kerley 's B line (n=3) and hilar enlargement (n=3) were also seen, and in one patient, HRCT demonstrated septal line thickening. Among four patients treated with prednisolone and Ara-C,three recovered and one CONCLUSION: In acute promyelocytic patients treated with all-trans-retinoic acid, radiologic findings of ill-de-fined consolidation, pleural effusion, hilar prominence and Kerley 's B line may suggest ATRA syndrome. The early diagnosis of this will improve the patients' prognosis.

HRCT Findings of Hypersensitivity Pneumonitis: Correlation with Pulmonary Function Test

PURPOSE: To evaluate the HRCT findings of hypersensitive pneumonitis and to correlate the findings with the results of the pulmonary function test (PFT). MATERIALS AND METHODS: Seven patients in whom hypersensitive pneumonitis was histologically confirmed (by transbronchial lung biopsy in two, thoracoscopic lung biopsy in one, open lung biopsy in two, and typical clinical and laboratory findings in two) were involved in this study. Their radiological patterns were assessed by HRCT and the extent of each finding was evaluated semi-quantitatively and correlated with the results of the pulmonary function test. RESULTS: The HRCT findings were as follows: lobular overinflation (n = 7), ground glass attenuation (n = 7), centrilobular nodule (n = 6), reticular opacity (n = 5), interlobular septal thickening (n = 3), consolidation (n = 2), and irregular subpleural line (n = 1). Five patients showed lower lung predominance and two, middle lung predominance. In all, a restrictive pattern and diminished diffusion capacity was noted. The grade score of reticular opacity showed significant correlation with forced vital capacity and forced expiratory volume. There was, however, no significant correlation between other HRCT findings and PFT results. Two patientsin whom lobular overinflation associated with parenchymal fibrosis was noted showed a decreased maximal midexpiratory flow rate of 25 -75. CONCLUSION: Lobular overinflation, ground-glass attenuation and centrilobular nodules are commonly observed in hypersensitive pneumonitis. The only significant correlation between each HRCT finding and the pulmonary function test was that between reticular opacity and both forced expiratory volume and forced vital capacity. In cases of chronic hypersensitive pneumonitis presenting as pulmonary fibrosis, associated lobular overinflation could be helpful for differential diagnosis.

Extensive acute lung injury following limited thoracic irradiation: radiologic findings in three patients

The aim of our study was to describe the radiologic findings of extensive acute lung injury associated with limited thoracic irradiation. Limited thoracic irradiation occasionally results in acute lung injury. In this condition, chest radiograph shows diffuse ground-glass appearance in both lungs and thin-section CT scans show diffuse bilateral ground-glass attenuation with traction bronchiectasis, interlobular septal thickening and intralobular smooth linear opacities.

Migrating Lobar Atelectasis of the Right Lung: Radiologic Findings in Six Patients

OBJECTIVE: To describe the radiologic findings of migrating lobar atelectasis of the right lung. MATERIALS AND METHODS: Chest radiographs (n = 6) and CT scans (n = 5) of six patients with migrating lobar atelectasis of the right lung were analyzed retrospectively. The underlying diseases associated with lobar atelectasis were bron-chogenic carcinoma (n = 4), bronchial tuberculosis (n = 1), and tracheobronchial amyloidosis (n = 1). RESULTS: Atelectasis involved the right upper lobe (RUL) (n = 3) and both the RUL and right middle lobe (RML) (n = 3). On supine anteroposterior radiographs (n = 5) and on an erect posteroanterior radiograph (n = 1), the atelectatic lobe(s) occupied the right upper lung zone, with a wedge shape abutting onto the right mediastinal border. On erect posteroanterior radiographs (n = 6), the heavy atelectatic lobe(s) migrated downward, forming a perior infrahilar area of increased opacity and obscuring the right cardiac margin. Erect lateral radi-ographs (n = 4) showed inferior shift of the anterosuperiorly located atelectatic lobe(s) to the anteroinferior portion of the hemithorax. CONCLUSION: Atelectatic lobe(s) can move within the hemithorax according to changes in a patient's position. This process involves the RUL or both the RUL and RML.

The Radiographic Spectrum of Pulmonary Complications in Major Burn Patient

In recent years, improved antibiotic care and physiologic fluid replacement in cases involving burn wounds have led to a decrease in the rate of fatalaties caused by wound sepsis and shock. There has, however, been an upsurge and relative increase in the frequency (15 -25%) and mortality rate (50 -89 %) of pulmonary complications. Since pulmonary lesions may result from direct injury to the respiratory tract caused by smoke inhalation, from circulatory, metabolic or infectious complications in cases involving cutaneous burns, or may develop during the therapeutic management of these lesions, a wide spectrum of pulmonary abnormalities can occur during the post-burn period. There is considerable overlap between their radiographic appearances, which are often nonspecific. Since the successful management of these patients is based on the early recognition and vig-orous treatment of lesions, familiarity with all facets of these complications, based on a pathophysiology of the injury and on the knowledge of the clinical setting, enables radiologists to make more specific diagnoses.

Plain Chest Radiographic Findings of Smoke Inhalation

PURPOSE: To evaluate the plain chest radiographic findings of smoke inhalation. MATERIALS AND METHODS:Our study included 72 burn patients who had suffered smoke inhalation. On admis-sion,all underwent serial portable chest AP radiography. We retrospectively reviewed the plain chest radi-ographs taken between admission and pootburn day five, evaluating the pattern, distribution, and time onset of direct injury to the respiratory system by smoke inhalation. The lesions were also assessed for change. RESULTS: In 16 of 72 patients (22%), abnormal findings of direct injury to the respiratory system by smoke in-halation were revealed by the radiographs. Abnormal findings were 15 pulmonary lesions and one subglottic tracheal narrowing. Findings of pulmonary lesions were multiple small patchy consolidations (10/15), peri-bronchial cuffing (8/15), and perivascular fuzziness (6/15). Patterns of pulmonary lesions were mixed alveolar and interstitial lesion (n=9), interstitial lesion (n=5), and alveolar lesion (n=1). No interlobular septal thicken-ing was observed. Pulmonary edema was distributed predominantly in the upper lung zone and perihilar re-gion, with asymmetricity. Its time of onset was within 24 hours in 13 cases, 24 -48 hours in two cases, and 48 -72 hours in one. Five of 16 patients progressed to ARDS. CONCLUSION: Chest radiographs showed that pulmonary lesions caused by inhalation injury were due to pul-monary edema, which the pattern of which was commonly mixed alveolar and interstitial.