The effects of electronic cigarette smoking on retinal nerve fiber layer, ganglion cell layer, inner plexiform layer, and choroidal thickness

PurposeTo compare the thickness of the retinal nerve fibre layer (RNFL), ganglion cell layer (GCL), inner plexiform layer (IPL), and choroid in healthy electronic cigarette smokers and non-smokers using spectral domain optical coherence tomography (SD-OCT).Material and Method25 healthy electronic cigarette smokers and 25 age- and gender-matched healthy non-smokers were included in the study. RNFL, GCL, IPL and choroidal thickness were measured by SD-OCT using an automated programme. After normality tests, an independent sample t-test was used to analyse the differences in RNFL, GCL, IPL, and choroidal thickness values between the groups.ResultsThe mean age of electronic cigarette smokers and non-smokers was 33.68 and 33.64 years, respectively. The mean smoking history was 6.6 years (range 5-8 years). Most of the participants smoked 2-5 ml of e-liquid per day (52%), while 36% smoked more than 5 ml and 12% smoked less than 2 ml per day. The mean intraocular pressure in the electronic cigarette smoker group was 15.0 mmHg, while the non-smoker group was 15.32 mmHg. The mean axial length in the electronic cigarette smoker group and non-smoker group was 23.36 and 23.63 mm, respectively. No significant difference was observed regarding RNFL, GCL, IPL or choroidal thickness between both groups.ConclusionThe thickness of the RNFL, GCL, IPL, and choroid was found to be similar in both the healthy electronic cigarette smokers and non-smokers groups.