Related Experiment Video
Updated: Sep 5, 2025

Electroencephalography Network Indices as Biomarkers of Upper Limb Impairment in Chronic Stroke
Published on: July 14, 2023
Evaluating the topographical measurements and tear function status in patients with hemifacial spasm: A comparative
Neslihan Bayraktar Bilen1, Sule Bilen2
1Department of Ophthalmology, Ankara Bilkent City Hospital, Ankara, Turkey.
Objective:
To investigate the effect of eyelid spasm on corneal and tear film characteristics in patients with hemifacial spasm (HFS) and compare these data with those of the contralateral eyes of the same patients.
Methods:
This prospective study is comprised of 64 eyes of 32 HFS patients, 32 eyes on the spasm side (Group 1) and 32 contralateral eyes (Group 2). Corneal tomographic analyses were performed; corneal power of flat axis (K1) and steep axis (K2), astigmatism and thinnest pachymetry; anterior, posterior and total corneal aberrometry [spherical aberration (SA), vertical coma (vcoma), horizontal coma (hcoma), total higher order aberration (THOA) and total RMS], and corneal densitometry values were evaluated and compared between groups. Tear meniscus height and depth (TMH, TMD) were measured using anterior segment optic coherence tomography. Tear function tests including TMH and TMD, the Schirmer I test, and tear break-up time (TBUT) were compared between the groups.
Results:
K1, K2, astigmatism and corneal densitometry values were similar between groups (p > 0.05). Thinnest pachymetry values were significantly thinner on the spasm side (p = 0.040). Anterior and total corneal SA and RMS were significantly higher on the spasm side (p = 0.032, p = 0.005; p = 0.015, p = 0.006, respectively). TMH, TMD and TBUT were significantly lower in Group 1 (p = 0.01, p = 0.02 and p = 0.03, respectively). Schirmer I test values were similar between groups (p > 0.05).
Conclusion:
In HFS patients, there are changes in corneal parameters and tear film in the eye on the spasm side compared to unaffected eye.

