Abstract
Purpose :
To investigate the characteristics of the shape of eyeballs that developed rhegmatogenous retinal detachment (RRD).
Methods :
The axial length (AL) and horizontal and vertical diameter (HD and VD, respectively) of eyeballs were measured using a newly developed wide-angle B-mode ultrasonography. The probe has an arc scan oscillator that can captures a 100 degree angle of field, whereas a conventional sector scan oscillator captures only approximately 52 degree. It can also measure eyeball diameter from the obtained images.
Sixty-five eyes of 65 subjects with RRD (RRD group) prior to surgery and 32 eyes of 32 subjects without RRD (NS group) were assessed. All subjects were 25-years old or older with AL 23–26 mm.
Results :
AL (RRD group: 24.7 ± 0.8 mm /NS group: 24.1 ± 0.9 mm) and HD (RRD: 21.1 ± 1.7 /NS: 20.5 ± 1.1) were significantly longer in the RRD group tan in the NS group (P < 0.01 and < 0.05, respectively). However, VD (RRD: 20.9 ± 1.8 /NS: 21.1 ± 1.7) did not differ significantly between the groups (P = 0.75). The ratio of HD to VD (HD/VD) was 1.010 ± 0.046 in the RRD group, which was statistically higher than that of 0.973 ± 0.040 in the NS group (P < 0.001).
Conclusions :
Surveillances using magnetic resonance imaging (MRI) have reported that myopic eyeballs are vertically longer on average (Atchison 2004, IOVS). Moreover, emmetropic eyes are also vertically long among the Japanese population (Watanabe 2011). Our results are consistent with previous reports of vertically long eyeballs, and to the best of our knowledge; our study is the first to report that RRD eyes are horizontally long on average by way of contrast.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.