Peripapillary Retinal Nerve Fiber Layer Thickness by Optical Coherence Tomography in Patients with Unilateral Amblyopia
Iraqi Postgraduate Medical Journal,
2021, Volume 20, Issue 1, Pages 91-98
Amblyopia is a common cause of unilateral visual defect, affecting patients with history of strabismus, refractive errors, and those who had visual deprivation in the critical period of visual development. Amblyopia may have an effect on various levels of the visual pathway. Cells atrophy in the lateral geniculate nucleus that receives information from the affected eye, and a shift in the dominance pattern in the visual cortex have been reported. Retinal involvement in amblyopia is controversial.
SUBJECTS AND METHODS:
This is a cross sectional study carried out in Al-Shaheed Ghazi al-Hareery Teaching Hospital in Medical City at Baghdad, Iraq .Forty-two patients with unilateral amblyopia were selected, 23 males and 19 females with age range of 12-40(mean age of 25.33 years) all of these patients had one amblyopic eye and the other eye normal. OCT scan was done for both eyes of each patient and the RNFLT measured after complete ophthalmological examination ( VA, refraction, slit lamp, and funduscopic examination
It has been noticed that the mean of NFLT in normal eyes was higher than that of amblyopic eyes (108.88 versus 105.05) but this difference was statistically not significant (P=0.074).
OCT is a sensitive way to estimate RNFLT, we concluded that there is no statistically significant difference in NFLT between the amblyopic, compared to the normal eyes. Also NFLT seems not affected by: type of amblyopia, age of patients and also the severity of amblyopia as all these factors didn’t reach statistical significant.
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