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This study was performed to identify the role of technetium-99m diethylene triamine penta-acetic acid ((99m)Tc DTPA) aerosol ventilation scintigraphy in the initial assessment and follow-up of children with bronchial asthma. In this prospective study conducted over a period of 2 years, 45 children (35M, 10F) aged 6-12 yrs (8.4 ± 2.2 years) with newly diagnosed moderate persistent bronchial asthma were included. Peak expiratory low (PEF) was measured and asthma symptom scores were calculated. Ventilation scintigraphy was performed after inhalation of (99m)Tc DTPA aerosol. The studies were repeated after 4 weeks of treatment with 400mcg budesonide daily. Pre and post treatment ventilation patterns were described, semiquantified and compared. Three patterns of ventilation were observed: a) homogenous (19/45), b) central airway deposition (21/45) and c) inhomogenous (5/45) with corresponding central: peripheral counts per pixel ratio of 1.265, 1.865 and 1.324 respectively. Ventilation pattern showed improvement (more counts in the periphery) in 22/45 children. Sixteen of 45 patients showed homogenous ventilation in both baseline and follow-up studies; abnormal central deposition was seen in both studies in 2/45. Five out of 45 children (3 with initial homogenous and 2 with initial inhomogenous patterns showed worsening on the follow-up scan after 4 weeks. In conclusion, semi-quantitave ventilation scintigraphy with (99m)Tc DTPA aerosol in asthmatic children repeated after 4 weeks treatment with budesonide showed better correlation with clinical symptom scores than PEF rates in monitoring response to treatment.