Failure to detect bitemporal field defects due to chiasmal compression on a screening perimetry protocol

Abstract

Chiasmal compression can present with a bitemporal decrease of colour and contrast sensitivity. Here, we compare the results obtained by the Amsler grid, confrontation to show red desaturation, the Tinsley suprathreshold, and the Humphrey 24-2 protocol in a patient with a pituitary adenoma. The initial Amsler chart was positive. The suprathreshold protocol, used as a screening method in many centers, gave a false-negative result. We discuss this important practical point in relation to the different stimulus attributes.