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Updated: Sep 29, 2025

O-cresol Concentration Online Measurement Based On Near Infrared Spectroscopy Via Partial Least Square Regression
Published on: November 8, 2019
THE USE OF NEAR INFRARED SPECTROSCOPY IN ALKAPTONURIA - THE MISLEADING OCHRONOSIS - A CASE REPORT AND LITERATURE
Carolina Mateus1, Ana Filipa Carvalho2, Ana Fonte Boa2
1Serviço de Anestesiologia, Centro Hospitalar do Porto, Porto, Portugal.
Introduction:
Near infrared spectroscopy is a non-invasive method to assess regional oxygenation and is being used in transcatheter aortic valve implantation to document periods of cerebral hypoperfusion, where cerebrovascular events are one of the most feared complications. Alkaptonuria is a rare metabolic disease characterized by accumulation of homogentisic acid in tissues and body fluids. The accumulation of pigment might interfere with the absorption of near infrared light, used in near infrared spectroscopy monitoring. We present a case of near infrared spectroscopy failing to accurately monitor cerebral oximetry in a woman, with alkaptonuria, undergoing a transcatheter aortic valve implantation.
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