Senile scleral plaques imaged with enhanced depth optical coherence tomography

PurposeSenile scleral plaques (SSP) are sharply demarcated greyish areas located just anterior to the insertions of the horizontal rectus muscles and thus are frequently encountered during transscleral intravitreal injections. The aim of this study was to characterize SSP using enhanced depth imaging spectral domain anterior segment optical coherence tomography (OCT) in a cohort of patients attending intravitreal injection clinics. MethodsProspective cross-sectional study of 380 patients attending the clinic for intravitreal injections at the Department of Ophthalmology at the Bern University Hospital. Thirty-two patients with SSP were identified and the anatomical features were assessed using anterior segment OCT. ResultsIn our patient cohort, we found a SSP prevalence of 8.2%. Senile scleral plaques were easily identifiable using anterior segment OCT and were found at the insertion sites of the horizontal recti muscles. The mean horizontal diameter was 2.2mm (760m SD), the mean vertical diameter was 3.3mm (+/- 144m SD), and the average surface area was 5.3mm(2) (+/- 0.4mm(2) SD). The mean senile scleral plaque thickness was 0.6mm (+/- 149m SD). The mean distance from the limbus was 2.24mm for nasally located SSP and 3.22mm for temporally located SSP. ConclusionSSP are frequently encountered during intravitreal injections as they are located just anterior to the insertion sites of the horizontal recti muscles. Because the scleral stroma is rarefied and due to calcifications within SSP, these areas should be avoided when performing multiple intravitreal injections as this may result in rupture of the sclera.