Title: Comparison of intraocular pressure & central corneal thickness amongst hypermetropes & myopes in adult Indian subjects
Authors: Dr Akshay Nayak, Dr Niveditha H, Dr Vishnuvardhan B
DOI: https://dx.doi.org/10.18535/jmscr/v7i7.98
Abstract
Background: Refractive error are one of the most common ocular disorders. Central corneal thickness (CCT) differs in myopia and hypermetropia, the differences in which can affect the measured Intraocular pressure (IOP).CCT & IOP also undergo changes with advancing age.
Aim: To measure difference in Intra ocular pressure between myopes and hypermetropes. To measure difference in central corneal thickness between myopes and hypermetropes. To note any variation in CCT and IOP that occurs with advancing age.
Materials & Methods: This was a prospective study comprising 104 myopic subjects and 136 hypermetropic subjects above age of 40 who went full ophthalmological examination with emphasis on IOP & CCT.
Results: The intraocular pressure (mmHg) was on the higher side in myopes (15.090, 15.490) whereas in hypermetropes (13.480,13.490). Intraocular pressure varies with age. As age advances there is a fluctuation in the measured IOP with a tendency to decrease, a higher IOP(14.53 mmHg, 14.61mmHg) was seen from ages 40 to 50 as compared to the other age groups. A thicker cornea was seen in hypermetropes (0.542mm, 0.543mm), while myopes (0,532mm,0.537mm) had a thinner cornea. A very weak correlation between IOP and CCT. (r=0.10 in both eyes for hypermetropes, r= -0.17, = -0.14 in myopes). Central corneal thickness was lower (0.523mm, 0.528mm) in advanced ages.
Conclusion: IOP was higher in myopes and hence at risk for glaucoma and IOP reduces as age advances. Thicker corneas are seen in hypermetropes leading to falsely high IOP readings and CCT was seen to reduce with age.
Keywords: Central corneal thickness, Intraocular pressure, Hypermetropia, Myopia,
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