Abstract

Purpose: This study aims to correlate accommodative, vergence parameters in myopia, hypermetropia and Emmetropia in young Nepalese population.

Methods: A cross sectional study design was conducted in subjects of Chitwan Eye Hospital, Bharatpur Nepal. All the samples underwent the measurement of uncorrected and corrected visual acuity and refraction. Then far and near cover tests were performed. The near point of convergence (NPC), accommodation, accommodation facility, negative relative accommodation (NRA) and positive relative accommodation (PRA) and vergence parameters for distance and near were evaluated in all participants. Statistical analysis was done using the one-way ANOVA and correlate bivariate in SPSS 16 Software.

Results: The mean age of the 108 participants was 22.95 ±3.17 years (18-35 years). The mean value of NRA was +2.88 ± 0.74 diopter (D) and PRA was -3.54 ± 1.15 (D) in total sample. Mean NRA and mean PRA was highest in hyperopic participants. The NRA was correlated with the Positive Fusional Vergence (PFV) distance in which significant (p < 0.040) and it was also correlated with the Negative Fusional Vergence (NFV) near with significant difference at the level of 0.05 (p < 0.03). But the NRA have no any statically correlation with the NFV distance in our study. The mean value of NFV in distance and near was 10.14 ± 3.40 prism diopter (PD) and 14.71 ± 5.48 prism diopter (PD), respectively. And the mean fusional value for PFV distance and near was 21.58 ±10.65 prism diopter (PD) and 23.14 ± 11.43 prism diopter (PD), respectively.

Conclusion: This study provides the normal range of NRA and PRA in Nepalese population. The results found in this study provides the direct relationship between NRA and PFV in hyperopic participants. Both NRA, PRA and NFV, PFV should considered when evaluating vergence and accommodative systems and even during orthoptic training. This study also provides the normal values of two parameter contributes to the diagnosis of the type of disorder and differential diagnosis.

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Citation

Citation: Mohammad Masihuzzaman., et al. “Relationship of Negative, Positive Relative Accommodation and Negative, Positive Fusional Vergence in Ammetropes and Emmetropes in a Young Population of Nepal". Acta Scientific Ophthalmology 4.1 (2021): 03-08.

Copyright

Copyright: © 2021 Mohammad Masihuzzaman., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.