Radioaerosol mucociliary clearance of tracheobronchial tree in normal subjects and in patients with respiratory diseases

The rate of mucociliary clearance in the tracheobronchial tree was studied both in patients and controls using radioisotopic techniques. The radioisotope is deposited in the larger airways and its rate of movement is measured as it is being transported up the trachea due to mucociliary activity. The BARC aerosol generation system was modified and used for this purpose. One hour study was acquired on a computerised gamma camera in each case. The rate of movement of the bolus of radioactivity was calculated by measuring the distance travelled in a known period of time. The mean velocity of transport was 9.0mm/min in normal subjects. In patients variable speed of transportation was obtained ranging from absolutely no movement to near normal speeds. Different patterns of transport were observed including linear, spiral, static and regurgitative. It was concluded that this simple non-invasive technique can be used for in vivo monitoring of mucociliary tracheal activity

Radio aerosol pulmonary imaging in COPD

Ninty five patients of chronic obstructive pulmonary disease [COPD] were subjected to radio-aerosol lung imaging to evaluate ventilatory function of the lungs, which was followed by lung profusion scanning. The patients were picked up randomly and the conventional ventilation studies were also done in addition to lung function tests and chest roentgenograms. The apparatus used was provided by the International Atomic Energy Agency. It generated aerosol particles of Tc-99m DTPA of pressure/vacuum air pump. Out of these 95 patients, 37 cases were those of bronchial asthma, 38 of chronic bronchitis, 5 of bronchietasis, 4 of chronic bronchitis with asthma, 3 with chronic bronchitis with emphysema, 2 with emphysema with bronchietasis and 6 were those of emphysema, Six normal subjects were taken as controls, A comparative study of all the performed lung function tests was done, We were able to detect defects of radio-aerosol pulmonary distribution even in those cases, where other lung function tests were not so conclusive. We conclude that the radio-aerosol pulmonary scanning is a very sensitive test and could be a valuable aid in diagnosis and follow up of cases of COPD