Isotope methods

Ventilation can be assessed by radioactive gas (e.g. xenon-133 or krypton-81m) or radiolabeled small particles (e.g. Technegas). Pulmonary blood flow is usually assessed with radiolabeled macroaggregated albumin or microspheres ( Diotefal 1.993). A typical application is the ventilation-perfusion scintigraphy used for the diagnosis of pulmonary emboli. A further development of the scintigraphic techniques has led to single-photon-emission CT where the gamma counter is moved around the body during the investigation and, if the condition under examination is stable, a two- or three-dimensional distribution of the isotope activity can be reconstructed.

Positron emission tomography can be used to estimate the lung blood flow, ventilation, ventilation-perfusion ratio, permeability to proteins, density of receptors, and many other biologically relevant aspects in vivo. However, this technique is an expensive research tool that is limited to a few research centers.

Was this article helpful?

0 0
Sleep Apnea

Sleep Apnea

Have You Been Told Over And Over Again That You Snore A Lot, But You Choose To Ignore It? Have you been experiencing lack of sleep at night and find yourself waking up in the wee hours of the morning to find yourself gasping for air?

Get My Free Ebook

Post a comment