Grant D. Aaker

Ultra-wide-field angiography improves the detection and classification of diabetic retinopathy.

Purpose: To evaluate patients with diabetic retinopathy using ultra–wide-field fluorescein angiography and to compare the visualized retinal pathology with that seen on an overly of conventional 7 standard field (7SF) imaging. Methods: Two hundred and eighteen eyes of 118 diabetic patients who underwent diagnostic fluorescein angiography using the Optos Optomap Panoramic 200A imaging system were included. The visualized area of the retina, retinal nonperfusion, retinal neovascularization, and panretinal photocoagulation were quantified by two independent masked graders. The respective areas identified on the ultra–wide-field fluorescein angiography image were compared with an overly of a modified 7SF image as outlined in the Early Treatment Diabetic Retinopathy Study. Results: Ultra–wide-field fluorescein angiograms imaging, on average, demonstrated 3.2 times more total retinal surface area than 7SF. When compared with 7SF, ultra–wide-field fluorescein angiography showed 3.9 times more nonperfusion (P < 0.001), 1.9 times more neovascularization (P = 0.036), and 3.8 times more panretinal photocoagulation (P < 0.001). In 22 eyes (10%), ultra–wide-field fluorescein angiography demonstrated retinal pathology (including nonperfusion and neovascularization) not evident in an 7SF overly. Conclusion: Compared with conventional 7SF imaging, ultra–wide-field fluorescein angiography reveals significantly more retinal vascular pathology in patients with diabetic retinopathy. Improved retinal visualization may alter the classification of diabetic retinopathy and may therefore influence follow-up and treatment of these patients.

Detection of retinal changes in Parkinson's disease with spectral-domain optical coherence tomography

Purpose This pilot study investigated whether high-resolution spectral-domain optical coherence tomography (SD-OCT) could detect differences in inner retinal layer (IRL), peripapillary retinal nerve fiber layer (RNFL), and macular thickness between patients with Parkinson’s disease (PD) and controls. Methods Both eyes of patients with PD and age-matched controls were imaged with the Heidelberg Spectralis® HRA + OCT. RNFL, IRL, and macular thickness were measured for each eye using Heidelberg software. These measurements were compared with validated, published normal values for macular and RNFL thickness, and compared with matched controls for IRL thickness. Results Eighteen eyes from nine subjects with PD and 19 eyes of 16 control subjects were evaluated using SD-OCT. The average age of PD patients was 64 years with a range of 52–75 years. The average age of controls was 67 years with a range of 50–81 years. No significant reduction in IRL thickness was detected between PD patients and age-matched controls at 13 points along a 6 mm horizontal section through the fovea. No significant difference in RNFL thickness was detected between PD patients and published normal values. Overall average RNFL thickness was 97 μm for PD patients, which exactly matched the normative database value. However, significant differences in macular thickness were detected in three of nine subfields between PD subjects and published normal values. In PD subjects, the outer superior subfield was 2.8% thinner (P = 0.026), while the outer nasal and inner inferior subfields were 2.8% (P = 0.016) and 2.7% (P = 0.001) thicker compared to published normal values. Conclusion In this pilot study, significant differences in macular thickness were detected in three of nine subfields by SD-OCT. However, SD-OCT did not detect significant reductions in peripapillary RNFL and IRL thickness between PD patients and controls. This suggests that macular thickness measurements by SD-OCT may potentially be used as an objective, noninvasive, and easily quantifiable in vivo biomarker in PD. Larger, longitudinal studies are needed to explore these relationships further.

Retinal nerve fiber layer evaluation in multiple sclerosis with spectral domain optical coherence tomography

Purpose: Histopathologic studies have reported retinal nerve fiber layer (RNFL) thinning in various neurodegenerative diseases. Attempts to quantify this loss in vivo have relied on time-domain optical coherence tomography (TDOCT), which has low resolution and requires substantial interpolation of data for volume measurements. We hypothesized that the significantly higher resolution of spectral-domain optical coherence tomography (SDOCT) would better detect RNFL changes in patients with multiple sclerosis, and that RNFL thickness differences between eyes with and without optic neuritis might be identified more accurately. Methods: In this retrospective case series, patients with multiple sclerosis were recruited from the Judith Jaffe Multiple Sclerosis Center at Weill Cornell Medical College in New York. Patients with a recent clinical diagnosis of optic neuritis (less than three months) were excluded. Eyes with a history of glaucoma, optic neuropathy (other than multiple sclerosis-related optic neuritis), age-related macular degeneration, or other relevant retinal and/or optic nerve disease were excluded. Both eyes of each patient were imaged with the Heidelberg Spectralis® HRA + OCT. RNFL and macular thickness were measured for each eye using the Heidelberg OCT software. These measurements were compared with validated published normal values, and were modeled as linear functions of duration of disease. The odds of an optic neuritis diagnosis as a function of RNFL and macular thickness were calculated. Results: Ninety-four eyes were prospectively evaluated using OCT. Ages of patients ranged from 26 to 69 years, with an average age of 39 years. Peripapillary RNFL thinning was demonstrated in multiple sclerosis patients; mean RNFL thickness was 88.5 μm for individuals with multiple sclerosis compared with a reported normal value of 97 μm (P < 0.001). Eyes with a history of optic neuritis had more thinning compared with those without optic neuritis (83.0 μm versus 90.5 μm, respectively, P = 0.02). No significant differences were observed in macular thickness measurements between eyes with and without optic neuritis, nor were macular thickness measurements significantly different from normal values. As a function of multiple sclerosis duration and controlling for age, RNFL thickness was decreased in patients with a duration of multiple sclerosis greater than five years compared with those with a duration less than or equal to one year (P = 0.008). Conclusions: Patients with a history of multiple sclerosis had RNFL thinning that was detectable on SDOCT. Decreasing RNFL thickness in eyes with optic neuritis was found, and the odds of having optic neuritis were increased significantly with decreasing RNFL thickness. Average RNFL thinning with increasing duration of disease was an excellent predictor of a reported history of optic neuritis. SDOCT retinal imaging may represent a high-resolution, objective, noninvasive, and easily quantifiable in vivo biomarker of the presence of optic neuritis and severity of multiple sclerosis.

Treatment of noninfectious posterior uveitis with dexamethasone intravitreal implant

Purpose To report our experience with dexamethasone 0.7 mg sustained-release intravitreal implant (Ozurdex®; Allergan, Inc, Irvine, CA) in noninfectious posterior uveitis. Methods A retrospective chart review of patients with noninfectious uveitis treated with sustained-release dexamethasone 0.7 mg intravitreal implant was performed. Complete ophthalmic examination including signs of inflammatory activity, visual acuity, fundus photography, fluorescein angiography, optical coherence tomography, and tolerability of the implant were assessed. Results Six eyes of 4 consecutive patients treated with a total of 8 dexamethasone 0.7 mg sustained-release intravitreal implants for posterior noninfectious uveitis were included. Two patients presented with unilateral idiopathic posterior uveitis; 2 patients had bilateral posterior uveitis, one secondary to sarcoidosis and the other to Vogt-Koyanagi-Harada syndrome. All eyes showed clinical and angiographic evidence of decreased inflammation following implant placement. Mean follow-up time post-injection was 5.25 months. Four eyes received 1 and 2 eyes received 2 Ozurdex implants during the follow-up period. The duration of effect of the implant was 3 to 4 months. No serious ocular or systemic adverse events were noted during the follow-up period. Conclusions In patients with noninfectious posterior uveitis, sustained-release dexamethasone 0.7 mg intravitreal implant may be an effective treatment option for controlling intraocular inflammation.

Evaluation of Vascular Disease Progression in Retinopathy of Prematurity Using Static and Dynamic Retinal Images

PURPOSE To measure accuracy and speed for detection of vascular progression in retinopathy of prematurity (ROP) from serial images. Two strategies are compared: static side-by-side presentation and dynamic flickering of superimposed image pairs. DESIGN Prospective comparative study. METHODS Fifteen de-identified, wide-angle retinal image pairs were taken from infants who eventually developed plus disease. Image pairs representing vascular disease progression were taken ≥1 week apart, and control images without progression were taken on the same day. Dynamic flickering pairs were created by digital image registration. Ten experts independently reviewed each image pair on a secure website using both strategies, and were asked to identify progression or state that images were identical. Accuracy and speed were measured, using examination date and ophthalmoscopic findings as a reference standard. RESULTS Using static images, experts were accurate in a mean (%) ± standard deviation (SD) of 11.4 of 15 (76%) ± 1.7 image pairs. Using dynamic flickering images, experts were accurate in a mean (%) ± SD of 11.3 of 15 (75%) ± 1.7 image pairs. There was no significant difference in accuracy between these strategies (P = .420). Diagnostic speed was faster using dynamic flickering (24.7 ± 8.3 seconds) vs static side-by-side images (40.3 ± 18.3 seconds) (P = .002). Experts reported higher confidence when interpreting dynamic flickering images (P = .001). CONCLUSIONS Retinal imaging provides objective documentation of vascular appearance, with potentially improved ability to recognize ROP progression compared to standard ophthalmoscopy. Speed of identifying vascular progression was faster by review of dynamic flickering image pairs than by static side-by-side images, although there was no difference in accuracy.

Three-Dimensional Reconstruction and Analysis of Vitreomacular Traction: Quantification of Cyst Volume and Vitreoretinal Interface Area

Author Affiliations: LuEsther T. Mertz Retinal Research Center, Manhattan Eye, Ear, and Throat Hospital and Vitreous Retina Macula Consultants of New York (Drs Vance and Freund), Department of Ophthalmology, New York University Medical Center (Dr Wald), and Department of Optometry, State University of New York College of Optometry (Dr Sherman), New York. Correspondence: Dr Freund, Vitreous Retina Macula Consultants of New York, 460 Park Ave, Fifth Floor, New York, NY 10022 (kbfnyf@aol.com). Financial Disclosure: None reported. Funding/Support: This study was supported by the Macula Foundation, Inc, New York, New York.

Volumetric three-dimensional reconstruction and segmentation of spectral-domain OCT.

Despite advances in optical coherence tomography (OCT), three-dimensional (3D) renderings of OCT images remain limited to scanning consecutive two-dimensional (2D) OCT slices. The authors describe a method of reconstructing 2D OCT data for 3D retinal analysis and visualization in a Computer Assisted Virtual Environment (CAVE). Using customized signal processing software, raw data from 2D slice-based spectral-domain OCT images were rendered into high-resolution 3D images for segmentation and quantification analysis. Reconstructed OCT images were projected onto a four-walled space and viewed through stereoscopic glasses, resulting in a virtual reality perception of the retina. These 3D retinal renderings offer a novel method for segmentation and isolation of volumetric images. The ability to manipulate the images in a virtual reality environment allows visualization of complex spatial relationships that may aid our understanding of retinal pathology. More importantly, these 3D retinal renderings can be viewed, manipulated, and analyzed on traditional 2D monitors independent of the CAVE.

PERIPHERAL VASCULAR ABNORMALITIES IN β-THALASSEMIA MAJOR DETECTED BY ULTRA WIDE-FIELD FUNDUS IMAGING.

PURPOSE To describe peripheral retinal vascular abnormalities in two patients with β-thalassemia major. METHODS Visual acuity testing, slit-lamp biomicroscopy, dilated fundus examination, ultra wide-field fundus photography, and fluorescein angiography were performed in two consecutive patients with β-thalassemia major. RESULTS Both patients had excellent visual acuity (20/20 and 20/25). Anterior segment examination was unremarkable. There were no lenticular changes noted in either patient. Dilated fundus examination was only remarkable for peripheral neovascular changes with preretinal hemorrhage in one patient and white without pressure in the other patient. Ultra wide-field fluorescein angiography revealed peripheral ischemia, vascular remodeling, active neovascularization, and arteriovenous anastomosis at the junction of perfused and nonperfused peripheral retina. One patient had sea fan neovascularization with active vitreous hemorrhage requiring peripheral laser photocoagulation. CONCLUSION As with patients with sickle cell disorder, patients with β-thalassemia major may require surveillance for peripheral vascular abnormalities, with treatment of these abnormalities before they result in permanent visual loss.