Correlation Analysis of Ocular Dominance and Levator Palpebrae Superioris Muscle Function

Ha, Ki Young; Suh, Hyeun Woo; Kim, Boo Yeong; Kim, Tae Yeon; Park, Sung Gyu

Abstract

PURPOSE
Most of the bilateral structures in our body are not perfectly balanced, such that one side is preferred than the other or it has physiological superiority. Eyes also have an imbalance; the eye with sensory and motional superiority compared to the other is called dominant eye. Authors of this study focused on analyzing the correlation between the dominant eye and levator palpebrae superioris muscle.
METHODS
The subject of this study was 42 patients with no ptosis and with no past history of blepharoplasty. Hand dominance was identified through questionnaire and dominant eye was identified by hole-in-the-card dominance test (Dolman's test) in all patients. The function of levator palpebrae superioris muscle was measured by MLD (marginal limbal distance). During the measuring procedure, frontalis muscle was not inhibited to avoid the eyelid skin hooding.
RESULTS
Out of 42 patients, 27 patients(64.3%) were right ocular dominant, 15 patients(35.7%) were left ocular dominant, 36 patients(85.7%) were right hand dominant and 4 patients(9.5%) were left hand dominant. Out of 27 right ocular dominant patients, right MLD was larger than the left in 26 patients(96.3%). It was larger in average of 0.47mm(p<0.001) in 27 right ocular dominant patients. Also, left MLD was larger than the right in 11 patients (73.3%) out of 15 left ocular dominant patients. It was larger in average of 0.57mm(p=0.003) in 27 left ocular dominant patients. MLD on the side of the dominant eye was larger in average of 0.50mm(p<0.001) than the MLD of non-dominant eye side. Right MLD was larger than the left in average of 0.28mm(p=0.010) in right hand dominant patients, and left MLD was larger than the right in average of 1.15mm(p=0.025) in left hand dominant patients.
CONCLUSION
The function of levator palpebrae muscle differs in right and left, and the difference correlates with the dominant eye. Also, the function of levator palpebrae muscle is stronger in the dominant eye. We were able to present statistical evidence regarding the difference of the function in right and left levator palpebrae muscle. This may be a factor worth consideration in terms of balancing the eyes during the blepharoplasty.