Use of Handheld Intraoperative Spectral-Domain Optical Coherence Tomography in a Variety of Vitreoretinal Diseases.

BACKGROUND AND OBJECTIVE: The use of intraoperative optical coherence tomography (iOCT) has been described with a variety of imaging devices and techniques. The purpose of this investigation is to examine the role of iVue (Optovue, Fremont, CA), a commercially available, handheld spectral-domain iOCT system, in vitreoretinal surgery. PATIENTS AND METHODS For this retrospective, observational case series, patients who underwent a vitreoretinal surgical procedure and were imaged with the iVue were identified. Images were qualitatively assessed. RESULTS: Five cases were identified, including an examination under anesthesia, epiretinal membrane, macular hole, retinal detachment, and non-clearing vitreous hemorrhage in the setting of proliferative diabetic retinopathy. CONCLUSION: Clinically useful images were obtained in all cases, though it was difficult to center the scan on the area of interest in the retina. Further work is necessary to improve system design and investigate the ways in which iOCT can aid in vitreoretinal surgery.

Analysis of short-term change in subfoveal choroidal thickness in eyes with age-related macular degeneration using optical coherence tomography.

BACKGROUND AND OBJECTIVE: To measure the subfoveal choroidal thickness in patients with age-related macular degeneration (AMD) over 6 months. PATIENTS AND METHODS: A retrospective, observational study of patients with AMD followed up for 6 months at the New England Eye Center. Baseline and 6-month follow-up subfoveal choroidal thickness was measured using spectral-domain OCT and compared. RESULTS: For the entire cohort, there was statistically significant thinning of the subfoveal choroidal thickness at 6 months compared to baseline that was driven by the cohort of patients with neovascular AMD (181.2 ± 75 µm to 173.4 ± 63 µm; P = .049). CONCLUSION: There was a statistically significant decrease in subfoveal choroidal thickness observed in this cohort of patients with AMD over 6 months, but it was driven by the subgroup of patients with neovascular age-related macular degeneration.

Analysis of the morphology and vascular layers of the choroid in retinitis pigmentosa using spectral-domain OCT.

BACKGROUND AND OBJECTIVE: To analyze choroidal morphology and vascular layers in eyes with retinitis pigmentosa (RP) using spectral-domain optical coherence tomography. PATIENTS AND METHODS: Cross-sectional, retrospective analysis of 14 patients (14 eyes) with RP and 33 healthy subjects (33 eyes) who underwent high-definition one-line raster scanning at a single center. Two independent raters evaluated the morphology, thickness, and vascular layers of the choroid in both groups. RESULTS: The choroid had an irregular shape in 11 of 14 eyes (79%) with RP. The thickest point of choroid was not subfoveal as in healthy eyes, and exaggerated nasal thinning of the choroid was observed in nine of 14 eyes (65%) with RP. Mean subfoveal total choroidal thickness and large choroidal vessel layer thickness were significantly lower in eyes with RP (P = .04 and P = .02, respectively) than in healthy eyes. CONCLUSION: Choroidal morphology is altered and an exaggerated thinning of the large choroidal vessel layer is observed in eyes with RP. Further studies involving correlation of disease stage and severity with choroidal changes may provide further insight into the involvement of choroid in RP and other inherited retinal dystrophies.

Analysis of choroidal morphologic features and vasculature in healthy eyes using spectral-domain optical coherence tomography.

OBJECTIVE: To analyze the morphologic features and vasculature of the choroid in healthy eyes using spectral-domain (SD) optical coherence tomography (OCT). DESIGN: Cross-sectional retrospective review. PARTICIPANTS: Forty-two healthy subjects (42 eyes) with no ocular disease who underwent high-definition scanning with Cirrus high-definition OCT (Carl Zeiss Meditec, Inc., Dublin, CA) at the New England Eye Center, Boston, Massachusetts, between November 2009 and September 2010. METHODS: The SD OCT images were evaluated for morphologic features of the choroid, including the shape of the choroid-scleral border, location of the thickest point of choroid, and regions of focal choroidal thinning. Total choroidal thickness and large choroidal vessel layer thickness were measured by 2 independent observers experienced in analyzing OCT images using the Cirrus linear measurement tool at the fovea, 750 µm nasal and temporal to the fovea. Custom software was used to calculate the ratio of choroidal stroma to the choroidal vessel lumen. MAIN OUTCOME MEASURES: Qualitative assessment of the choroidal morphologic features, quantitative analysis of choroidal vasculature, and use of novel automated software to determine the ratio of choroidal stromal area to the area of choroidal vessel lumen. RESULTS: The 42 subjects had a mean age of 51.6 years. All subjects (100%) had a so-called bowl or convex shape to the choroid-sclera junction, and the thickest point of the choroid was under the fovea in 88.0% of the subjects. The mean choroidal thickness was 256.8 ± 75.8 µm, mean thickness of the large choroidal vessel layer was 204.3 ± 65.9 µm, and that of the medium choroidal vessel layer-choriocapillaris layer was 52.9 ± 20.6 µm beneath the fovea. The ratio of large choroidal vessel layer thickness to the total choroidal thickness beneath the fovea was 0.7 ± 0.06. The software-generated ratio of choroidal stromal area to the choroidal vessel lumen area was 0.27 ± 0.08, suggesting that choroidal vessel lumen forms a greater proportion of the choroid than the choroidal stroma in healthy eyes. CONCLUSIONS: This is the first study to describe the morphologic features and vasculature of the choroid in healthy eyes from 1-line raster scans obtained using SD OCT. The method described holds promise and has immediate clinical usefulness in recognizing subtle changes in choroidal morphologic features and the role of choroidal angiopathy in various disease states that, in the future, may inform new treatment methods. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.