Scintigraphic Evaluation of Inhalation Injury in Fire Victims / 핵의학분자영상

PURPOSE: Conventional chest X-ray and pulmonary function test cannot sensitively detect inhalation injury. Bronchoscopy is known to be the gold standard but it is invasive method. We evaluated whether lung inhalation/perfusion scans can sensitively detect inhalation injury of fire victims. MATERIALS AND METHODS: Nineteen patients (male 9, female 10, mean age 31.6 yr) of fire victims were enrolled in this study. Inhalation lung scan was performed 2 days later after inhalation injury with 99mTc-technegas. Perfusion lung scan was performed 4 days later with 99mTc-MAA (macroaggregated albumin). Follow up lung scans were performed 16 and 18 days later for each. Chest X-ray was performed in all patients and bronchoscopy was performed in 17 of 19 patients at the same period. Pulmonary function test was performed in 9 patients. RESULTS: Four of 19 patients showed inhalation and perfusion defects and one showed inhalation defect but, normal perfusion scan findings. These five patients with abnormal scan findings showed abnormal bronchoscopic findings and severe respiratory symptoms. On chest X-ray, 2 of them had pulmonary tuberculosis and one of them showed pulmonary congestion. FEV1/FVC was abnormal in 3 patients. On the follow up scan, all patients with abnormal initial scan findings showed improved findings and they had improved clinical state. CONCLUSION: Inhalation/perfusion lung scans can detect inhalation burn injury noninvasively in early stage and may be useful in therapeutic decision making and follow up of patients.

Comparison of Inhalation Scan and Perfusion Scan for the Prediction of Postoperative Pulmonary Function / 결핵

BACKGROUND: Because of the common etiologic factor, such as smoking, lung cancer and chronic obstructive Pulmonary disease are often present in the same patient. The preoperative prediction of remaining pulmonary function after the resectional surgery is very important to prevent serious complication and postoperative respiratory failure. 99mTc-MAA perfusion scan has been used for the prediction of postoperative pulmonary function, but it may be inaccurate in case of large V/Q mismatching. We compared 99mTc-DTPA radioaerosol inhalation scan with 99mTc-MAA perfusion scan in predicting postoperative lung function. METHOD: Preoperative inhalation scan and/or perfusion scan were performed and pulmonary function test were performed preoperatively and 2 month after operation. We predicted the postoperative pulmonary functions using the following equations. Postpneumonectomy FEV1=Preop FEV1x% of total function of lung to remain RESULTS: 1) The inhalation scan showed good correlations between measured and predicted FEV1, FVC and FEF25-75%. (correlation coefficiency; 0.94, 0.91, 0.87 respectively). 2) The perfusion scan also showed good correlations between measured and predicted FEV1, FVC and FEF25-75%. (correlation coefficiency; 0.86, 0.72, 0.97 respectively). 3) Among three parameters, FEV1 showed the best correlations in the prediction by lung scans. 4) Comparison between inhalation scan and perfusion scan in predicting pulmonary function did not show any significant differneces except FVC. CONCLUSION: The inhalation scan and perfusion scan are very useful in the prediction of postoperative lung function and don't make a difference in the prediction of pulmonary function although the former showed a better correlation in FVC.