Tc-99m Technegas scintigraphy to evaluate the lung ventilation in patientswith oral corticosteroid-dependent bronchial asthma

Bronchial asthma is a clinical syndrome characterized by the reversibility of airway obstruction. Recently it has been suggested that remodeling of th e airway causes irreversible airway obstruction which may be responsible fo r the patient's symptoms. With this background, the purpose of the present study was to assess patients with corticosteroid-dependent asthma by Tc-99m Technegas scintigraphy (Technegas) in both planar and SPECT images. Twelve patients (7 females and 5 males aged 36-72 years with a median age of 60 y ears: 4 smokers and 8 non-smokers) with oral corticosteroid-dependent asthm a were enrolled in this study. Lung ventilation scanning with Technegas in both planar and SPECT images, high-resolution computed tomography, and pulm onary function tests were performed in all patients. The results of Techneg as scanning were graded and correlations with other clinical parameters wer e evaluated. Significant abnormalities were detected by ventilation scintig raphy with Technegas in patients with corticosteroid-dependent bronchial as thma even during remission Our data demonstrate that airflow obstruction to ok place patients with corticosteroid-dependent asthma even during remissio n. Technegas scanning appears to be a useful radiopharmaceutical for demons trating airflow obstruction in patients with bronchial asthma.