Digital Algorithmic Diabetic Retinopathy Severity Scoring System (An American Ophthalmological Society Thesis).

PURPOSE: To develop a new diabetic retinopathy severity scoring system and to determine if it can monitor changes from baseline as well as identify precise features that have changed over time. Such a grading system could potentially provide an understanding of the impact of treatments utilizing an algorithmic scoring technique. METHODS: The traditional ETDRS grading system was examined and a flow algorithm based on the grading approach was created. All visual comparative assessment points, relying on identification of features in relation to prior standard photographic images, were evaluated and quantified. A new grading form was created that provided fields that captured all relevant features required for determining the ETDRS grading score. A computer software algorithm was developed that examines all entered fields and calculates the appropriate diabetic severity score. RESULTS: This diabetic retinopathy scoring algorithm system was successful in generating a severity score comparable to traditional methods of grading images. Validation with traditionally graded images was performed, demonstrating that in a majority of cases, the severity scores were comparable. The algorithmic grading system was then used to analyze images obtained in a large clinical study of diabetic macular edema, resulting in data regarding baseline scoring values, as well as detailed features of the microvasculature that drove the severity scoring results, and changes seen during the trial. CONCLUSION: This new algorithmic diabetic severity scoring system provides a means to monitor the progression or regression of retinopathy with therapeutic intervention as well as assess the individual microvascular features that may be modified over the course of treatment.

Subretinal hyperreflective exudation associated with neovascular age-related macular degeneration.

PURPOSE: To describe the multimodal imaging findings of subretinal hyperreflective exudation (SHE) observed in association with choroidal neovascularization and to distinguish SHE from other forms of subretinal hyperreflective material (SHM) seen in patients with age-related macular degeneration and other macular disorders. METHODS: A retrospective study on 46 eyes of 42 patients with SHE associated with Types 1, 2, and 3 choroidal neovascularization secondary to neovascular age-related macular degeneration. Patients were examined using multimodal imaging, including color photography, near-infrared reflectance imaging, spectral domain optical coherence tomography, fluorescein angiography, fundus autofluorescence imaging, and indocyanine green angiography. Clinical and imaging characteristics were evaluated at baseline, after the initiation of intravitreal antivascular endothelial growth factor therapy, and during the resolution of SHE. RESULTS: Forty-five of the 46 eyes were treatment naive. The mean ± SD age at the first detection of SHE was 77.2 ± 10.1 years. The mean ± SD follow-up was 2.1 ± 0.6 years. Fluorescein angiography was performed in 42 eyes and demonstrated leakage and/or staining of underlying or adjacent choroidal neovascularization but not of the SHE itself in all eyes. On fluorescein angiography, SHE was transparent in 29 eyes and blocking in 7 eyes. In 32 eyes, SHE showed isoautofluorescence on fundus autofluorescence imaging, and in 8 eyes, SHE showed varying degrees of hyperautofluorescence. Indocyanine green angiography was performed in eight eyes and demonstrated hyperfluorescence of SHE in seven eyes. In eight eyes, SHE was the only evidence of neovascular activity. All eyes having follow-up (42 eyes) showed resolution of the subretinal material with partial or full reconstitution of the ellipsoid zone after a median of 2 injections range (1-16 injections). Subretinal hyperreflective exudation persisted for a median of 9 weeks (range, 4-60 weeks) after the initiation of treatment. The mean visual acuity before treatment was 0.619 (20/83), and it improved to 0.380 (20/48) (P = 0.03) after the resolution of SHE. CONCLUSION: Subretinal hyperreflective exudation differs from other types of SHM based on the findings from multimodal imaging. This novel type of SHM likely represents a sign of active neovascular age-related macular degeneration distinct from subretinal fluid, hemorrhage, neovascular tissue, lipid, pigment hyperplasia, subretinal fibrosis, and the SHM observed with acquired vitelliform lesions. Intravitreal antivascular endothelial growth factor agents can be used to successfully resolve SHE, often resulting in better visual outcomes in eyes manifesting this form of exudation.

Varying difficulty of Snellen letters and common errors in amblyopic and fellow eyes.

OBJECTIVE: To investigate the varying difficulty of Snellen letters in children with amblyopia. METHODS: We tabulated the letter-by-letter responses of amblyopic and nonamblyopic fellow eyes on random, computer-generated Snellen lines. Participants were 60 children, aged 5 to 13 years, with a history of amblyopia. Main outcome measures were relative difficulties of Snellen letters and common misidentifications. RESULTS: Errors were 7.5 times more common with certain letters (B, C, F, S) than with others (A, L, Z, T), this difference increasing to 17.6-fold at threshold. Similar relative letter difficulty was demonstrated at lines above and at visual acuity thresholds, and both difficult and easy letters were the same for amblyopic and nonamblyopic fellow eyes. Specific misidentification errors were often repeated and were often reciprocal (eg, B for E and E for B). CONCLUSION: Since therapeutic decisions in amblyopia management are often based on small differences in visual acuities, the relative difficulties of letters used in their measurement should be considered. The Early Treatment Diabetic Retinopathy Study system should be considered for use in this clinical setting.