Background: Visual disturbances caused by smoking have been studied extensively though the pathogenesis is poorly understood. The significance to diagnose visual field disturbances because of smoking is that prognosis for return of vision is always good if the consumption of tobacco is restrained timely.
Aims & Objective: To study visual field in healthy smokers.
Materials and Methods: In this study, subjects from the outpatient clinic were selected randomly: 30 healthy smokers and 30 nonsmokers. These subjects were divided into two groups: test (smokers) and control (nonsmokers). Ocular examination of all the subjects was done including intraocular pressure measurement and fundus examination. Further, visual field analysis was carried out using an automated perimeter (M700; Medmont International). Then, interpretation of visual field was done along with assessment of visual field defects. Values obtained were analyzed using Z-test and unpaired Students t-test. p-Value less than 0.05 was considered to be statistically significant.
Results: Average deviation (AD) and patterned deviation (PD) were found to be significantly high in smokers as compared to nonsmokers (p < 0.001). It was also observed that AD and PD were significantly high if the smoking load (average number of cigarettes multiplied by average duration of smoking) is more than 50,000 (p < 0.005 and p < 0.02, respectively). In smokers, retinal sensitivity was found to decrease and the presence of localized scotomas was observed, but the central vision was found to be preserved.
Conclusion: This study is important in diagnosing visual field defects in tobacco amblyopia to stop nicotine toxicity in time with early intervention, thereby preventing further damage to the optic nerve.
Key words: Smokers; Visual Field; Scotoma; Retinal Sensitivity; Perimeter
|
