Researchers recently discovered dipping a glaucoma patient’s hand into cold water caused the mean sensitivity of their visual field to decrease—but only if they had concurrent Flammer syndrome. As part of their investigation into whether or not visual field defects can be reversible in some instances, researchers from Poland and Switzerland tested the effects of cold provocation in 10 primary open-angle glaucoma patients (POAG) with Flammer syndrome, seven POAG patients without Flammer syndrome and 11 controls.

Previous research suggests cold provocation—i.e, cooling a patient’s hand—can lead to temporary visual function changes. The investigators speculated that this may be of increased importance in patients with glaucoma and Flammer syndrome because the latter conditions is accompanied by vascular dysregulation and compromised ocular blood flow.

The researchers examined visual fields using the standard white-on-white static computerized perimetry before and after cold provocation. Patients immersed their non-dominant hand in cold (4° Celsius) water for two minutes.

The data showed only those with Flammer syndrome had significantly decreased mean sensitivity after cold provocation compared with baseline. While visual field recovery was not a part of the study, the researchers noted seven of the 10 glaucoma patients with Flammer syndrome showed complete recovery when they returned within six to eight months for repeat visual field testing.      

“The visual field deterioration induced by cooling a hand is most likely the result of the reduction of the ocular blood flow,” the researchers wrote in the study. And the increased vasospastic response to cold is a potential risk factor for glaucomatous optic neuropathy, they concluded.

Terelak-Borys B, Grabska-Liberek I, Schoetzau A, Konieczka K. Transient visual field impairment after cold provocation in glaucoma patients with Flammer syndrome. Restor Neurol Neurosci. February 5, 2019. [Epub ahead of print].