Table 3.

Advantages and disadvantages of future imaging modalities.

Imaging Modality	Advantages	Disadvantages
Dynamic 4-D CT scans	Accurately demonstrates tracheobronchomalacia. Demonstrates structures adjacent to the tracheobronchial tree. Non-invasive. Fast. Allows for 3D reconstruction.	Limited availability. Perceived to impart a higher radiation dose than bronchography.
Newer MRI techniques	Provide ventilation and perfusion images in a single acquisition. Shorter acquisition times. No radiation exposure.	High cost. Limited availability.
Positron emission tomography (PET)/CT	Highly sensitive in active TB. Reliably differentiates between active and latent disease. Assists with assessing response to treatment.	Limited availability. Low specificity with solitary pulmonary nodules.
Computer aided detection software (CAD)	Acceptable sensitivity (90%) and specificity (70%) of a TB triage test. Cost-effective. User friendly. No human expertise needed to interpret	Sparse literature regarding performance in paediatrics. Lower sensitivities in older patients and those with previous TB.