Study on the changes of circumpapillary retinal nerve fiber layer thickness after ocular contusion

Abstract

Objective To observe the changes of circumpapillary retinal nerve fiber layer (cpRNFL) thickness and the correlation with visual field defect (VFD) in patients with ocular contusion. Methods Twenty-four eyes of 24 patients with ocular contusion were collected in this study. Nineteen patients were male and 5 were female. The age ranged from 18 to 45 years old with a mean of (31.13±9.02) years. The thickness of cpRNFL of all patients were examined by optical coherence tomography (OCT) 10 days, 1, 3, 6 and 9 months after ocular trauma. The examinations of mean visual field defect (MVFD) were performed in traumatic eyes. Data of best corrected visual acuity (BCVA) and the correlation between thickness of cpRNFL and VFD were recorded. The mean follow-up time was(1.22±0.43) years with a range from 10 months to 2 years. Results There was an increased trend in BCVA 1 month after trauma (F=5.473, P=0.000), and then the BCVA kept stable (F=0.026, P=0.994). The mean thickness of cpRNFL of the non-trauma eye was (100.58±12.62) μm. The mean thickness of cpRNFL was (88.96±11.11)μm 10 days after trauma.The thickness of cpRNFL had a decreased trend 3 months after trauma with a significant regression 1 month after the trauma (F=25.977, P=0.000). The MVFD were (-3.58±2.30) dB and (-5.63±2.18) dB 10 days and 1 month after respectively. There was a regressive trend in VFD after ocular trauma with a stable level 3 months after the trauma (F=14.965, P=0.000). There was a positive correlation between the decrease of cpRNFL thickness and VFD after ocular blunt trauma (r=0.646, P=0.000). Conclusion The thickness of cpRNFL decreases after ocular blunt trauma, and is stable 3 months after the trauma. There is a correlation between cpRNFL thickness and VFD, and the more the decrease of cpRNFL thickness is, the more the defect of the visual field will be. Key words: Retinal nerve fiber layer, circumpapillary (cpRNFL); Ocular contusion; Visual field