Noninvasive Medical Techniques

I found Aaron Rowe’s article on noninvasive optical medical diagnosis techniques interesting (C&EN, Jan. 2, page 25). However, I was surprised that there was no mention of two commonly used existing techniques: pulse oximetry and transcutaneous bilirubinometry. The former is something most of us are familiar with, utilizing red and infrared light to measure blood oxygen levels through a fingertip. The latter measures skin bilirubin levels using multiple-wavelength light-emitting diodes, then correlates the result to the total serum bilirubin levels in preterm infants with neonatal jaundice.

Recently, I was happy to see both techniques being used in the treatment of my premature child (along with phototherapy for the jaundice). More than a matter of convenience or pain avoidance, these techniques are important when the patient’s blood supply is limited or susceptible to infection.

By Dave VanderWiel
Brecksville, Ohio