Abstract
Purpose: :
To evaluate if changes in the area and volume of vascularized retinal pigment epithelial detachments (PEDs) following anti-VEGF therapy using spectral domain optical coherence tomography imaging (SDOCT) and a novel quantitative algorithm can be used to predict the need for retreatment using an OCT-guided retreatment strategy.
Methods: :
Patients with AMD and vascularized PEDs treated with anti-VEGF therapy were enrolled in this retrospective study. Only patients managed using an OCT-guided "as-needed" retreatment strategy were included. Retreatment was given only when recurrent or persistent subretinal or intraretinal fluid was detected. Changes in PED area and volume were then assessed retrospectively before and after anti-VEGF therapy. Five separate SDOCT scans were performed on each eye, each consisting of 40,000 uniformly spaced A-scans organized as a 200 X 200 A-scan array. Each raster scan covered a retinal area of 6x6 mm encompassing the entire PED. A novel algorithm was used to quantitatively assess PED area and volume.
Results: :
Fourteen eyes from 14 patients were identified. All retreatment decisions were based on the qualitative appearance of the SDOCT images and not on the quantitative assessments of PEDs obtained using the novel algorithm. When the novel algorithm was used to assess the changes in PED area and volume measurements, it was found that in all the visits in which an injection was withheld due to the absence of any recurrent of subretinal or intraretinal fluid, an injection was needed at the next visit (8 visits involving 7 different patients). At the visit where the injection was withheld, the algorithm showed that the PED had increased in area and volume measurements beyond the test-retest variability and prior to the recurrence of subretinal or intraretinal fluid at the subsequent visit. These increases in the PED measurements preceded the need for injection at the next follow-up visit.
Conclusions: :
SDOCT imaging in conjunction with this novel algorithm to assess PED area and volume measurements appear to provide a valuable strategy for evaluating PEDs undergoing anti-VEGF therapy, especially when using an OCT-guided retreatment regimen.
Keywords: age-related macular degeneration • imaging/image analysis: clinical • vascular endothelial growth factor