Growdon_1997_Arch.Neurol_54_841

Reference

Title : Pupil dilation to tropicamide is not specific for Alzheimer disease - Growdon_1997_Arch.Neurol_54_841
Author(s) : Growdon JH , Graefe K , Tennis M , Hayden D , Schoenfeld D , Wray SH
Ref : Archives of Neurology , 54 :841 , 1997
Abstract :

BACKGROUND: The extent of pupil dilation after instillation of a dilute tropicamide solution was proposed as a noninvasive neurobiological diagnostic test for Alzheimer disease (AD). Pupils in patients with AD dilated 23% vs only 5% in control subjects. OBJECTIVE: To determine whether pupil dilation in response to tropicamide distinguishes patients with AD from control subjects without dementia.
METHODS: There were 50 patients with AD and 51 control subjects; no participant had primarily ocular pathological conditions or took drugs that affected cholinergic tone. All participants received 1 drop of 0.01% tropicamide in 1 eye and 1 drop of 0.9% saline solution in the other eye in random order. Pupil measurements were obtained using a pupil and corneal reflection tracking system (RK-426 PC system, ISCAN Inc, Burlington, Mass) that illuminated the eye with a low-level infrared source and measured pupil diameters, fixation, and light level every 16.7 milliseconds during each 30-second-measurement. Pupil measurements were obtained from each eye at baseline and 5, 10, 15, and 30 minutes after drop instillation.
RESULTS: The increase in pupil size after tropicamide instillation was equal between patients with AD and control subjects. The mean (+/- SD) pupil diameter increased from 4.5 +/- 1.1 to 5.5 +/- 1.1 mm after 30 minutes in patients with AD and from 4.7 +/- 0.9 to 5.8 +/- 0.9 mm in control subjects. Anisocoria and the mean rate of dilation did not differ between patients with AD and control subjects. Eye color and corneal moisture did not affect these results. The extent of pupil dilation in patients with AD was not related to clinical estimates of dementia severity. CONCLUSION: Pupil dilation in response to instillation of 0.01% tropicamide is not useful as an antemortem diagnostic test for AD.

PubMedSearch : Growdon_1997_Arch.Neurol_54_841
PubMedID: 9236572

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Citations formats

Growdon JH, Graefe K, Tennis M, Hayden D, Schoenfeld D, Wray SH (1997)
Pupil dilation to tropicamide is not specific for Alzheimer disease
Archives of Neurology 54 :841

Growdon JH, Graefe K, Tennis M, Hayden D, Schoenfeld D, Wray SH (1997)
Archives of Neurology 54 :841