Three-Dimensional Enhanced Imaging of the Vitreoretinal Interface in Eyes with Diabetic Retinopathy Using Swept-Source Optical Coherence Tomography

Abstract

Purpose: To demonstrate in-vivo three-dimensional enhanced imaging of the posterior vitreous and the vitreoretinal interface in eyes with diabetic retinopathy using a long-wavelength swept-source optical coherence tomography (SS-OCT) prototype.

Methods: Thirteen patients with diabetes (21 eyes) with or without clinical evidence of diabetic retinopathy as determined by a complete ophthalmic examination performed by a retina specialist, were prospectively recruited for imaging on a prototype long-wavelength (1050nm) SS-OCT system with 6µm resolution and 3.6mm imaging range. Up to eight orthogonally scanned three-dimensional SS-OCT volumes consisting of 500x500 axial scans were acquired for each eye over a 12x12mm region (~40 degrees) of the retina. A registration algorithm was applied to remove motion artifacts and merge multiple volumes to improve signal. Visualization of the posterior vitreous and the vitreoretinal interface was enhanced using a high dynamic range (HDR) method.

Results: Of the 21 eyes, 15 eyes had clinical features suggestive of diabetic retinopathy, while 6 eyes had no clinical evidence of diabetic retinopathy. Of the 15 eyes that had diabetic retinopathy, 6 eyes had non-proliferative diabetic retinopathy, 5 eyes had proliferative diabetic retinopathy and 4 eyes had diabetic macular edema. Enhancement of the posterior vitreous and the vitreoretinal interface using the HDR method showed hyaloid detachment near the optic disk in 19 of 21 eyes (90%) and hyaloid detachment elsewhere in 18 of 21 eyes (86%). Of the 15 eyes with clinical evidence of diabetic retinopathy, the detached hyaloid appeared thickened in 6 of 15 eyes (40%) when compared to eyes without diabetic retinopathy. Vitreoschisis was observed in 8 of 15 eyes (53%), fibrovascular adhesions between the detached hyaloid and retina were seen in 7 of 15 eyes (47%) and vitreous aggregations/clumps were visible in 9 of 15 eyes (60%) with diabetic retinopathy.

Conclusions: SS-OCT with registration followed by application of the HDR method provides wide-field three-dimentional information of the posterior vitreous and the vitreoretinal interface in eyes with diabetic retinopathy. A detailed observation of these features may be useful in assessing the progression of diabetic retinopathy, planning diabetic vitreous surgery and predicting treatment outcomes.

Keywords: 499 diabetic retinopathy • 550 imaging/image analysis: clinical • 688 retina