Community-acquired pneumonia: a correlative study between chest radiographic and HRCT findings.

PURPOSE: To elucidate what kinds of lesions tend to be overlooked or misinterpreted and why they were overlooked or misinterpreted on chest radiographs in the diagnosis of community-acquired pneumonia (CAP) by comparing radiographic findings with HRCT findings. MATERIALS AND METHODS: In 129 patients with CAP (107 bacterial and 22 atypical) and 105 healthy subjects, the chest radiographic findings were correlated with the HRCT findings. The diagnostic accuracy of each chest radiographic finding was evaluated by comparing it with the HRCT finding. RESULTS: The false negative rate of radiographic interpretation tended to be higher for nodules and thickening of the bronchial wall, especially in patients with atypical pneumonia. The most frequent reason for false negative interpretations of nodules and bronchial wall thickening was the overlapping of these findings with airspace consolidation or ground-glass opacity (GGO). Thin lesions were the most frequent reasons for the false negative interpretation of airspace consolidation and GGO. CONCLUSION: The chest radiographic interpretations of GGO and airspace consolidation were influenced by the thickness of lesions, and those of nodules and thickening of bronchial walls were influenced by coexisting GGO and airspace consolidation and may contribute to a misinterpretation of these lesions and an incorrect diagnosis of CAP.

High-resolution computed tomography findings of influenza virus pneumonia: a comparative study between seasonal and novel (H1N1) influenza virus pneumonia.

PURPOSE: To evaluate the high-resolution computed tomography (HRCT) findings of novel influenza virus (n-IFV) pneumonia and compare them with the findings for seasonal (s-IFV) pneumonia. MATERIALS AND METHODS: We evaluated 29 cases of pure IFV pneumonia that occurred between 1990 and 2010. We evaluated the existence, extent, and patterns of HRCT findings and compared these features between s-IFV and n-IFV. RESULTS: Consolidation was less frequent in s-IFV than in n-IFV (40.0 vs. 84.2%, respectively; p = 0.014). Consolidation with a loss of volume was frequent in n-IFV (62.5%). There was no significant difference in the occurrence of ground-glass opacity (GGO) between s-IFV and n-IFV (100 vs. 84.2%, respectively). GGO with reticular opacities was more frequent in s-IFV than in n-IFV (70.0 vs. 25.0%, respectively; p = 0.024). The frequency of nodules was not significantly different between the two groups. The mosaic pattern was more frequent in s-IFV than in n-IFV patients (80.0 vs. 15.8%, respectively; p = 0.0007). Mucoid impaction was more frequent in patients with n-IFV than with s-IFV (52.6 vs. 10.0%, respectively; p = 0.025). CONCLUSIONS: Consolidation and mucoid impaction were more frequent in n-IFV, whereas GGO with reticular opacities and a mosaic pattern occurred more frequently in s-IFV; otherwise, there were no significant differences between the two groups.

Esophageal ruptures: triage using the systemic inflammatory response syndrome score.

Esophageal rupture is a rare entity. Delay in the diagnosis and treatment may threaten the patient's life. The decision for surgical or nonsurgical treatment, however, remains controversial because advocates of both treatments have reported comparable results. To quantify the decision making, we suggest the systemic inflammatory response syndrome (SIRS) score for triage of an esophageal rupture. Using this criterion for 12 patients resulted in the survival of all of them. Therefore, we advocate use of the SIRS score for triage of an esophageal rupture.

[A case of drug-induced interstitial pneumonia due to phenytoin].

A 48-year-old woman had been given phenytoin for prevention of epilepsy for 30 years. She developed a dry cough and low grade fever from one year and half before admission to our hospital. During this interval, she was treated with various antibiotics, however, her condition did not improve. A chest radiograph and CT showed diffuse reticular ground glass opacities in bilateral lung fields. A drug lymphocyte stimulation test (DLST) for phenytoin showed positive results. Lung biopsy specimen by VATS revealed predominant lymphocytic infiltration of lung parenchyma, compatible with drug-induced pneumonitis. Administration of phenytoin was discontinued, oral administration of 30 mg prednisolone was initiated, and the symptoms and shadow on X-ray films improved. These observations strongly suggested the presence of drug-induced pneumonia due to phenytoin in this patient. In patients who develop pneumonia not associated with infection, the possibility of drug-induced pneumonia should be always considered even though the drug has been administered for a long period.

[Chemotherapy for non-small cell lung cancer: split-dose administration of Cisplatin over four consecutive days and Vinorelbine ditartrate].

PURPOSE: At present, combination chemotherapy with Cisplatin (CDDP) and Vinorelbine ditartrate (VNR) is one of the standard regimens for non-small cell lung cancer (NSLC). To avoid renal damage by CDDP, hydration and diuretic are indicated. But elderly/postoperative patients who have reduced lung vessel capacity are a high-risk group for pulmonary edema/right heart failure by hydration. In our hospital, CDDP is administered on four consecutive days without large hydration. MATERIAL & METHODS: CDDP: 80 mg/m2 (over four consecutive days)without large hydration+VNR: 20 mg/m2 was administered 30 NSLC patients(Stage III A & IV). Serum concentration of CDDP was monitored. RESULT: Response rate was CR: 0 case; PR: 9 cases; SD: 16 cases; PD: 5 cases. Mean survival time (MST) was 292 days. The efficacy and prognosis are equivalent to a conventional CDDP+VNR regimen. On the other hand, side effects were reduced; neutrocytopenia (> Grade 3): 17%, renal dysfunction (>Grade 1): 17%. Mean serum concentrations of CDDP were accumulated day by day, 0.91 microg/mL(Day 1), 2.44 microg/mL(Day 4), but were all under the toxic threshold(8 microg/mL). CONCLUSION: Our regimen (CDDP given over four consecutive days without large hydration) may become a regimen for the high-risk patient.

Inhalational lung injury due to nitrogen dioxide: high-resolution computed tomography findings in 3 patients.

Chest radiographic and high-resolution computed tomography findings of 3 patients with inhalational lung injury due to nitrogen dioxide were reported. Chest radiographs showed ill-defined round opacities which tended to coalesce in both lung with inner lung predominance. High-resolution computed tomography showed ground-glass attenuation and ill-defined centrilobular nodules distributed predominantly in the inner and middle lung zones. One patient showed progression of opacities, which corresponded to the findings of acute respiratory distress syndrome.

Rheumatoid arthritis-related lung diseases: CT findings.

PURPOSE: To evaluate computed tomographic (CT) findings of rheumatoid arthritis-related lung disease and categorize findings according to pathologic features. MATERIALS AND METHODS: CT scans obtained in 63 patients (27 men, 36 women; mean age, 61.7 years +/- 11.2 [SD]; range, 28-81 years) with rheumatoid arthritis were assessed. Mean duration of disease was 7.6 years +/- 9.2. Lung parenchymal abnormalities that included airspace consolidation, ground-glass opacity (GGO), reticulation, honeycombing, nodules, bronchiectasis, and air trapping were assessed retrospectively by two chest radiologists. Final decision was reached with consensus of these radiologists and a third radiologist. Patients were classified according to the predominant CT pattern. One of the chest radiologists and a pulmonary pathologist compared CT findings with pathologic findings in 17 patients. Interobserver agreement between the first two radiologists was assessed. Correlation between CT finding extent score and pulmonary function test results was estimated with Spearman rank correlation coefficient. RESULTS: GGO (57 [90%] patients) and reticulation (62 [98%] patients) were the most common CT features. Four major CT patterns were identified: usual interstitial pneumonia (n = 26), nonspecific interstitial pneumonia (n = 19), bronchiolitis (n = 11), and organizing pneumonia (n = 5). Usual interstitial pneumonia and nonspecific interstitial pneumonia CT patterns overlapped; GGO was more extensive in patients with nonspecific interstitial pneumonia CT pattern (P =.028). In 17 patients who underwent biopsy, CT findings reflected pathologic findings. Exceptions were two patients classified with usual interstitial pneumonia at CT but with nonspecific interstitial pneumonia at pathologic analysis; one patient, with nonspecific interstitial pneumonia at CT but desquamative interstitial pneumonia at pathologic analysis; and one patient, with lymphoid interstitial pneumonia at CT but nonspecific interstitial pneumonia at pathologic analysis. CONCLUSION: Rheumatoid arthritis is associated with four CT patterns: usual interstitial pneumonia, nonspecific interstitial pneumonia, bronchiolitis, and organizing pneumonia. The most common CT features of rheumatoid arthritis-related lung disease were GGO and reticulation.

[Two cases of radiation myositis probably induced by recall phenomenon].

Two cases of radiation myositis following gemcitabine-based chemotherapy for advanced non-small cell lung cancer are presented. In the two cases, myositis appeared 3 and 5.5 months after the completion of radiation therapy and 2 and 2.5 months after the beginning of chemotherapy, respectively. The affected areas, the upper back and right thigh, appeared as areas of increased signal intensity on T2-weighted MR imaging and were enhanced by the administration of Gd-DTPA in the skeletal muscles. These coincided with the previously irradiated area. Although radiation myositis is a rare complication, it is important to be careful of radiation recall induced by chemotherapeutic agents.

HRCT findings of pulmonary complications in non-AIDS immunocompromised patients: are they useful in differential diagnosis?

PURPOSE: This study was designed to evaluate the diagnostic value of characteristic HRCT findings in the differential diagnosis of acute pulmonary complications (APCs) in immunocompromised patients and to investigate how to improve diagnostic accuracy. MATERIALS AND METHODS: We reviewed the chest CT images of 103 consecutive immunocompromised non-AIDS patients with APCs. The presence, extent, and anatomical distribution of the CT findings were assessed by two radiologists. The sensitivity and positive predictive value (PPV) of each criterion determined by the combination of CT findings that were characteristic in previous studies were calculated. RESULTS: The average sensitivity of each criterion was 0.50 in the total cases. There were many false positives, and the PPVs of some criteria were low. Among the significantly less frequent CT findings, the frequency of bronchovascular bundle thickening was 0% in cytomegaloviral pneumonia (CMV P). The absence of this finding improved the diagnostic accuracy of CMV P. CONCLUSION: Because the combination of only characteristic HRCT findings in each disease was of relatively limited value in making a diagnosis, infrequent findings should be also added to the CT criteria to improve accuracy.

The probability of malignancy in small pulmonary nodules coexisting with potentially operable lung cancer detected by CT.

The aim of this study was to assess the probability of malignancy in one or two small nodules 1 cm or less coexisting with potentially operable lung cancer (coexisting small nodules). The preoperative helical CT scans of 223 patients with lung cancer were retrospectively reviewed. The probability of malignancy of coexisting small nodules was evaluated based on nodule size, location, and clinical stage of the primary lung cancers. Seventy-one coexisting small nodules were found on conventional CT in 58 (26%) of 223 patients, and 14 (6%) patients had malignant nodules. Eighteen (25%) of such nodules were malignant. The probability of malignancy was not significantly different between two groups of nodules larger and smaller than 0.5 cm ( p=0.1). The probability of malignancy of such nodules within primary tumor lobe was significantly higher than that in the other lobes ( p<0.01). Metastatic nodules were significantly fewer in clinical stage-IA patients than in the patients with the other stage ( p<0.01); however, four (57%) of seven synchronous lung cancers were located in the non-primary tumor lobes in the clinical stage-I patients. Malignant coexisting small nodules are not infrequent, and such nodules in the non-primary tumor lobes should be carefully diagnosed.

Air trapping at CT: high prevalence in asymptomatic subjects with normal pulmonary function.

PURPOSE: To determine the degree and extent of air trapping at computed tomography (CT) in subjects with normal pulmonary function test results. MATERIALS AND METHODS: The study group consisted of 50 subjects with normal pulmonary function, including 26 nonsmokers and 24 smokers (14 current and 10 ex-smokers; 11 mild and 13 heavy smokers). All 50 subjects underwent thin-section CT at which images were obtained during deep inspiration and expiration at three lung levels. The mean expiratory increase in lung attenuation was measured at each level. Air trapping was visually classified into four degrees (none, lobular, mosaic, or extensive), and the extent of air trapping was also semiquantitatively calculated. The visual grade and semiquantitative ratio of air trapping were compared among nonsmokers, current smokers, and ex-smokers and among nonsmokers, mild smokers, and heavy smokers by using the Kruskal-Wallis rank test and the Fisher protected least significant difference test, respectively. RESULTS: The mean increase in lung attenuation in the three levels at expiration was 111.9 HU +/- 46.3 (SD). The overall frequency of air trapping was 64%. Lobular, mosaic, and extensive air trapping were seen in 10 (20%), 14 (28%) and eight (16%) patients, respectively. There was no significant difference in the visual grade of air trapping among the nonsmokers, current smokers, and ex-smokers (P =.387) or among the nonsmokers, mild smokers, and heavy smokers (P =.231). There was also no significant difference in the semiquantitative ratio of air trapping among nonsmokers, current smokers, and ex-smokers (P =.859) or among nonsmokers, mild smokers, and heavy smokers (P =.897). CONCLUSION: Various degrees of air trapping, including the mosaic or extensive types, can be observed in subjects with normal pulmonary function and have no correlation with the subject's current smoking status or cigarette consumption.

[Early effect of intra-arterial chemotherapy combined with degradable starch microspheres for malignant hepatic tumors].

The hepatic artery-embolizing effect of degradable starch microspheres (DSM) was assessed by dynamic CT scanning soon after embolization in patients with malignant hepatic tumors. Using the Seldinger method, DSM with a mixture of contrast medium, MMC, ADM or Epi-ADM was manually injected. The subjects were 32 patients with metastatic carcinoma of the liver (62 treatments) and 15 patients with hepatocellular carcinoma(19 treatments) (47 patients received 81 treatments in all). Dynamic CT scanning was performed within 2 weeks of each embolization procedure, and the percent reduction in the area visualized (necrotic effect) was calculated to assess the efficacy of embolization. The necrotic effect of embolization was classified as CR, PR, NC, and PD after 9, 41, 10, and 2 treatments, respectively, in the patients with metastatic carcinoma of the liver and after 4, 6, 6, and 3 treatments, respectively, in the patients with hepatocellular carcinoma. Although there was no patient in whom the tumor showed 50% or more reduction, the contrast enhanced area showed 50% or more decrease in 60 out of 81 treatments. Therefore, blocking of blood flow seemed to contribute more to the response than enhancement of the efficacy of the anticancer agents. Adverse reactions were all transient and controllable. Based on our results, intra-arterial chemotherapy plus DSM embolization seems to be useful for treating malignant hepatic tumors.

HRCT findings of chest complications in patients with leukemia.

High-resolution CT (HRCT) findings of several chest complications occurring in leukemic patients were reviewed. Although most entities show non-specific HRCT findings including ground-glass opacity and air-space consolidation, characteristic findings are observed in several pulmonary complications including Pneumocystis carinii pneumonia, fungal infections, miliary tuberculosis, leukemic infiltration, pulmonary edema, bronchiolitis obliterans, and bronchiolitis obliterans organizing pneumonia. A combination of these characteristic HRCT findings and the information obtained from the clinical setting may help in achieving a correct diagnosis of chest complications occurring in leukemic patients.

CT findings of leukemic pulmonary infiltration with pathologic correlation.

The aim of this study was to demonstrate the characteristic CT findings of leukemic pulmonary infiltration based on the pathologic findings. The CT findings of 11 leukemic patients with leukemic pulmonary infiltration were compared with those of 22 leukemic patients with other diseases as a control group. Evaluated pulmonary parenchymal CT findings included thickening of bronchovascular bundles and interlobular septa, prominence of peripheral pulmonary arteries, ground-glass opacities, air-space consolidation, and nodules. The CT-pathologic correlations for leukemic infiltration were evaluated in 7 patients. Frequent parenchymal CT findings were thickening of bronchovascular bundles (81.8%), prominence of peripheral pulmonary arteries (81.8%), and non-lobular and non-segmental ground-glass opacities (90.9%). The first two findings were significantly more frequently observed in leukemic infiltration than in the control group, had good interobserver agreement, and corresponded pathologically to leukemic cell infiltration around the pulmonary arteries, bronchi, or bronchioles. Non-lobular and non-segmental ground-glass opacity corresponded to leukemic cell infiltration within alveolar spaces and septa adjacent to the pulmonary arteries or bronchi and also corresponded to hemorrhage, edema, or diffuse alveolar damage. Thickening of bronchovascular bundles and prominence of peripheral pulmonary arteries are CT findings suggestive for leukemic infiltration and correspond to peribronchovascular tumor extension.

Imaging findings of an intercostal hemangioma.

SUMMARY: The authors present the imaging findings in a 44-year-old woman with a rare intercostal hemangioma that originated from the connective tissue between the intercostal muscle and parietal pleura and protruded into the thoracic cavity. The contrast-enhanced computed tomography (CT) showed a markedly enhancing mass, whereas dynamic magnetic resonance (MR) images showed heterogeneous and strong enhancement with incomplete early eccentric enhancement peripherally followed by complete filling-in on delayed scans. The imaging features of CT and MR imaging of a hemangioma may be useful for proper preoperative diagnosis.