Douglas W. J. Mackey

Learn More
Mucociliary clearance (MCC) is an important mechanism for removing inhaled particles, secretions and cellular debris from the respiratory tract. Here, a direct measurement of tracheal mucus velocity (TMV) for assessment of MCC, suitable for clinical and research use, is reported, and a comparison is made of TMV in normal subjects and patients with chronic(More)
Planar pulmonary scintigraphy is currently the standard investigation for the diagnosis of pulmonary embolism. There are a number of problems with the technique, particularly in patients with an intermediate scan report under the PIOPED criteria. The technique is also under threat from the increasing use of spiral CT angiography. A putative improvement may(More)
Pneumocystis carinii pneumonia (PCP) has become a major cause of morbidity and mortality due to infectious diseases, largely as a result of the acquired immunodeficiency syndrome (AIDS) epidemic. Since the mortality from recurrent infection is between 40% and 60%, early diagnosis and therapy are the keys to survival. The role of technetium 99m diethylene(More)
A virtual model of the segmental scintigraphic anatomy of the lungs was used to investigate the threshold at which small defects are perceptible. A model of the segmental anatomy of the lungs was developed from a number of sources and counts generated within the phantom by Monte-Carlo simulation of photon emission. Multiple subsegmental defects were created(More)
Technegas, an ultra-fine dry aerosol with prolonged retention in the lungs, can be modified by altering the atmosphere in which the carbon particles are generated. The modified Technegas has much faster clearance from the lung. The half-time pulmonary clearances with modified Technegas were compared to those obtained with conventional 99mTc DTPA aerosol in(More)
A retrospective review of 37 children with a variety of solid tumors who underwent 60 67Ga single-photon emission computed tomographic (SPECT) studies was performed. These studies were correlated with clinical and radiological findings and, where possible, histopathologic confirmation. In all studies, SPECT gave better definition and better anatomic(More)
The aim of this study was to establish nomograms of renal length in children comparing age, body weight, and height. Renal lengths were obtained from data derived from Tc-99m DMSA scintigraphy in 266 patients with 532 kidneys that appeared normal on DMSA studies. The children's ages ranged from 6 days to 19 years. Renal length appeared to have nonlinear(More)
UNLABELLED The diagnostic probability of pulmonary embolic disease is based on the recognition of unmatched segmental perfusion defects. Although interobserver and intraobserver reproducibility have been studied, accuracy has been an elusive goal due to the lack of a gold standard. We investigated the accuracy and reproducibility of reporting in a virtual(More)