Intraocular epidermal growth factor concentration, axial length, and high axial myopia

Purpose Various molecules such as dopamine have been found to be associated with axial elongation in experimental studies. Here, we examined whether intraocular EGF is associated with axial length in myopic patients. Methods The hospital-based investigation included patients of European descent without optic nerve, retinal, or macular diseases except for myopic maculopathy. Using aqueous humor samples collected during surgery, the EGF concentration was examined applying a cytometric bead array. High myopia was defined by an axial length of >= 27.0 mm. Results The study included a non-highly myopic group of 11 patients (mean age, 72.9 +/- 10.8 years; mean axial length, 24.3 +/- 1.1 mm) and a highly myopic group of three patients (age, 81.11 +/- 12.3 years; axial length, 29.5 +/- 1.3 mm), with one of them having pathologic myopic maculopathy. In multivariable linear regression analysis, higher EGF concentration was correlated with the highly myopic versus non-highly myopic group (beta, 1.24; non-standardized correlation coefficient B, 6.24; 95% confidence interval (CI), 0.10,12.4;P = 0.047) after adjusting for axial length. The amount of intraocular EGF was significantly higher in the highly myopic group than in the non-highly myopic group (89.1 +/- 40.8 pg versus 34.1 +/- 13.2 pg; P = 0.005), and it was highest in the eye with myopic maculopathy (135 pg). Conclusions The intraocular amount of EGF is higher in highly myopic versus non-highly myopic eyes.