Usefulness of Cervical Computed Tomography Hounsfield Units to Differentiate Kawasaki Disease From a Deep-neck Abscess.

We measured the Hounsfield units (HUs) value of cervical plain computed tomography images to differentiate between Kawasaki disease (KD) and a deep-neck abscess (DNA). The HUs value was significantly lower in KD than in DNA, making it a useful marker for differentiating between these 2 diseases.

Radiotherapy for thoracic tumors: association between subclinical interstitial lung disease and fatal radiation pneumonitis.

BACKGROUND: We evaluated the association between subclinical interstitial lung disease (ILD) and fatal radiation pneumonitis (RP) in patients with thoracic tumors treated with thoracic radiotherapy (RT). METHODS: Sixty-two consecutive patients with thoracic tumors treated with thoracic RT were retrospectively analyzed. According to our protocols, patients with subclinical ILD (untreated and asymptomatic) were considered to be indicated for thoracic RT, while patients with clinical ILD (post- or during treatment) were not considered candidates for thoracic RT. The presence, extent and distribution of subclinical ILD on CT findings at pre-thoracic RT were reviewed and scored by two chest radiologists. The relationships between RP and clinical factors, including subclinical ILD, were investigated. RESULTS: Subclinical ILD was recognized in 11 (18 %) of the 62 patients. Grade 2-5 RP was recognized in eight (13 %) of the 62 patients, with Grade 5 in three patients and Grade 2 in five patients. Grade 2-5 RP was observed in four (36 %) of the 11 patients with subclinical ILD. Subclinical ILD was found to be a significant factor influencing the development of Grade 2-5 RP (p = 0.0274). Subclinical ILD tended to be significant for the occurrence of Grade 5 RP (p = 0.0785). Regarding the CT score, more extensive ILD (bilateral fibrosis in multiple lobes) was recognized in two of the three patients with Grade 5 RP. CONCLUSIONS: In this study, fatal RP tended to be more common in the patients with subclinical ILD. In particular, the presence of extensive fibrosis on CT may be a contraindication for thoracic RT.

Palliative radiotherapy in patients with a poor performance status: the palliative effect is correlated with prolongation of the survival time.

BACKGROUND: The purpose of this study was to analyze the efficacy and tolerability of palliative radiotherapy (RT) in patients with a poor performance status (PS) and to evaluate the relationship between the palliative effect and survival time. METHODS: One hundred and thirty-three patients with a poor PS (Eastern Cooperative Oncology Group 3 or 4) were treated with palliative RT using the three-dimensional conformal technique and retrospectively analyzed. Each patient's primary symptom treated with palliative RT as the major cause of the poor PS was evaluated using the second item of the Support Team Assessment Schedule (STAS) at the start and one week after the completion of palliative RT. RESULTS: One hundred and fourteen (86%) of the 133 patients completed the planned palliative radiation dose. Grade 3 acute toxicity was observed in two patients (2%) and Grade 2 acute toxicity was observed in 10 patients (9%). No Grade 2 or higher late toxicities were observed, except for Grade 3 radiation pneumonitis in one patient. Improvement in the STAS scores between pre- and post-palliative RT was recorded in 76 (61%) of the 125 patients with available scores of STAS. A significant improvement in the mean STAS score between pre- and post-palliative RT was recognized (p < 0.0001). Improvement in the STAS score was found to be the most statistically significant prognostic factor for overall survival after palliative RT in both the multivariate and univariate analyses. The median overall survival time in the patients with an improvement in the STAS score was 6.4 months, while that in the patients without improvement was 2.4 months (p < 0.0005). CONCLUSIONS: Palliative RT in patients with a poor PS provides symptomatic benefits in more than half of patients without inducing severe toxicities. The palliative effect is strongly correlated with prolongation of the survival time and may contribute to improving the remaining survival time in patients with metastatic/advanced cancer with a poor PS.

Improved detection of lung cancer arising in diffuse lung diseases on chest radiographs using temporal subtraction.

RATIONALE AND OBJECTIVES: The purpose of this study was to evaluate the usefulness of temporal subtraction for the detection of lung cancer arising in pneumoconiosis, idiopathic pulmonary fibrosis, and pulmonary emphysema. MATERIALS AND METHODS: Fifteen cases of lung cancer arising in diffuse lung diseases, including three cases of pneumoconiosis, six of idiopathic pulmonary fibrosis, and six of pulmonary emphysema, were evaluated. Pathologic proof was obtained by surgery or transbronchial lung biopsy. The average interval between previous and current radiographs was 356 days (range, 31-947 days). All chest radiographs were obtained with a computed radiography system, and temporal subtraction images were produced by subtracting of a previous image from a current one with a nonlinear image-warping technique. The effect of the temporal subtraction image was evaluated by observer performance study with receiver operating characteristic analysis. RESULTS: The average observer performance with temporal subtraction was significantly improved (Az = 0.935) compared with that without temporal subtraction (Az = 0.857, P < .0001). CONCLUSION: The temporal subtraction technique is useful for the detection of lung cancer arising in pneumoconiosis, idiopathic pulmonary fibrosis, and pulmonary emphysema.

Usefulness of an artificial neural network for differentiating benign from malignant pulmonary nodules on high-resolution CT: evaluation with receiver operating characteristic analysis.

OBJECTIVE: The purpose of our study was to use an artificial neural network to differentiate benign from malignant pulmonary nodules on high-resolution CT findings and to evaluate the effect of artificial neural network output on the performance of radiologists using receiver operating characteristic analysis. MATERIALS AND METHODS: We selected 155 cases with pulmonary nodules less than 3 cm (99 malignant nodules and 56 benign nodules). An artificial neural network was used to distinguish benign from malignant nodules on the basis of seven clinical parameters and 16 radiologic findings that were extracted by attending radiologists using subjective rating scales. In the observer test, 12 radiologists (four attending radiologists, four radiology fellows, and four radiology residents) were presented with high-resolution CT images, first without and then with the artificial neural network output. Observer performance was evaluated by means of receiver operating characteristic analysis using a continuous rating scale. RESULTS: The artificial neural network showed a high performance in differentiating benign from malignant pulmonary nodules (A(z) = 0.951). The average A(z) value for all radiologists increased by a statistically significant level, from 0.831 to 0.959, with the use of the artificial neural network output. CONCLUSION: Our computerized scheme using the artificial neural network can improve the diagnostic accuracy of radiologists who are differentiating benign from malignant pulmonary nodules on high-resolution CT.