Exploration of the cutoff values of axial length that is susceptible to develop advanced primary open angle glaucoma in patients aged less than 50 years.

PURPOSE

To examine the correlation of the spherical equivalent refraction (SER) and axial length with the visual field, and to determine cutoff values of SER and axial length for the risk of developing advanced primary open-angle glaucoma (POAG).

METHODS

Patients with POAG or secondary glaucoma were retrospectively enrolled from a clinical database at Kyoto University Hospital between August 2011 and December 2018. Correlations between the mean deviation (MD) and axial length were evaluated in these patients using the Pearson's correlation coefficient. Advanced POAG was defined as having an MD of less than -12 dB as measured by the Humphrey visual field analyzer (HFA). The cutoff values of the axial length and SER for the risk of developing advanced POAG were determined using Fisher's exact test and Youden's J statistic for HFA 24-2 and 10-2, respectively.

RESULTS

This study included 741 eyes of 438 patients. In POAG, axial length was negatively correlated with the MDs of the HFA 24-2 and 10-2. However, in secondary glaucoma, axial length did not significantly correlate with the MDs of the HFA. The cutoff axial length for the HFA 24-2 was 27.7 mm. For HFA 10-2, two peaks for the Youden's J statistic were observed, at 27.67 mm and 25.51 mm. No significant association was found between SER and severity of visual field changes.

CONCLUSIONS

Axial length measurement was clinically significant in assessing risk of severe or central visual field defects in young patients with POAG.