Optical Coherence Tomography Segmentation Errors of the Retinal Nerve Fiber Layer Persist Over Time.

PRéCIS:: There are errors in automated segmentation of the retinal nerve fiber layer (RNFL) in glaucoma suspects or patients with mild glaucoma that appear to persist over time; however, automated segmentation has greater repeatability than manual segmentation. PURPOSE: To identify whether optical coherence tomography (OCT) segmentation errors in RNFL thickness measurements persist longitudinally. METHODS: This was a cohort study. We used spectral domain OCT (Spectralis) to measure RNFL thickness in a 6-degree peripapillary circle, and exported the native "automated segmentation only" results. In addition, we exported RNFL thickness results after "manual refinement" to correct errors in the automated segmentation, and used the differences in these measurements as "error" in segmentation. We used Bland-Altman plots and linear regression to determine the magnitude, location, and repeatability of RNFL thickness error in all twelve 30-degree sectors and compared the error at baseline to follow-up time points at 6 months, 2 years, 3 years, and 4 years. RESULTS: We included 406 eyes from 213 participants. The 95% confidence interval for errors at baseline was -6.5 to +13.2 µm. The correlation between the baseline error and the errors in the follow-up time periods were high (r>0.5, P<0.001 for all). Automated segmentation had a smaller SD of residuals from the longitudinal trend line when compared to manual refinement (1.56 vs. 1.80 µm, P<0.001), and a higher ability (P=0.009) to monitor progression using an analysis of a longitudinal signal-to-noise ratio. CONCLUSIONS: Errors in automated segmentation remain relatively stable, and baseline error is highly likely to persist in the same direction and magnitude in subsequent time periods. However, automated segmentation (without manual refinement) is more repeatable and may be more sensitive to glaucomatous progression. Future segmentation algorithms could exploit these findings to improve automated segmentation in the future.

Optical coherence tomography angiography of a pigmented Fuchs' adenoma (age-related hyperplasia of the nonpigmented ciliary body epithelium) masquerading as a ciliary body melanoma.

PURPOSE: To report a case of age-related hypertrophy of the nonpigmented ciliary epithelium (ARH-NPCE) clinically resembling a ciliary body melanoma and report the optical coherence tomography angiography (OCTA) findings associated with this lesion. OBSERVATIONS: A 51-year-old male was referred for evaluation of a deeply pigmented ciliary body mass with extension through the iris root. Iridocyclectomy was performed due to concern for ciliary body melanoma. Histopathologic analysis was instead consistent with ARH-NPCE, also known as Fuchs' adenoma. Prior to surgery, OCTA images revealed abnormal vasculature in the area of the lesion. Vessels in the peripheral iris approaching the lesion appeared more tortuous and were non-radial as compared with normal iris vessels. The ciliary body mass itself could not be penetrated using an OCTA system operating at 1050 nm. CONCLUSIONS AND IMPORTANCE: ARH-NPCE may clinically resemble a pigmented ciliary body melanoma. This is the second case describing this clinical scenario, which may be more common than previously thought. Non-invasive imaging with OCTA revealed an abnormal peripheral iris vasculature pattern in the area of the iridociliary mass characterized by disorganized, tortuous, and non-radial vessels. Despite advances in longer wavelength OCTA systems, poor penetration of the ciliary body lesion precluded imaging of the intratumoral vessels in this location.

Cytokines and chemokines in the vitreous fluid of eyes with uveal melanoma.

PURPOSE: In uveal melanoma, both tumor size and an inflammatory phenotype have been shown to correlate with a poor clinical prognosis. The purpose of this study was to identify whether inflammatory cytokines were present in the vitreous of eyes with uveal melanoma and to determine whether the vitreal concentration of cytokines correlated with prognostic variables such as tumor dimensions and immune cell infiltrate. METHODS: Vitreous was acquired from patients with uveal melanoma (n = 33) and from control eyes with no known ocular conditions (n = 9), and analyzed using a 27-plex cytokine bead array. Immunofluorescence testing was performed to determine the presence of macrophages, CD4(+), CD8(+), and Foxp3(+) regulatory T cells (T(regs)). RESULTS: Compared with control eyes, eyes with uveal melanoma demonstrated higher vitreal concentrations of many cytokines and chemokines, including IL-6, IL-8, IP-10, MCP-1, MIP-1α, MIP-1ß, TNF-α, and RANTES. IL-1ra was decreased in the vitreous of tumor-bearing eyes compared with controls. Tumor prominence positively correlated with several cytokines, including IL-6, IL-8, IP-10, MCP-1, MIP-1α, MIP-1ß, TNF-α, RANTES, GCSF, IFN-γ, and VEGF. IL-6 and IP-10 were found to positively correlate with increasing regulatory T-cell infiltrate and IL-6 alone positively correlated with macrophage infiltration. CONCLUSIONS: Eyes with uveal melanoma contain higher vitreal concentrations of several inflammatory cytokines and chemokines that correlate predominantly with increasing tumor size; elevations in certain cytokines and chemokines also correlate with the presence of immune cell infiltrate.

Genetics of primary intraocular tumors.

Primary intraocular neoplasms are tumors that originate within the eye. The most common malignant primary intraocular tumor in adults is uveal melanoma and the second is primary intraocular lymphoma or vitreoretinal (intraocular) lymphoma. The most common malignant intraocular tumor in children is retinoblastoma. Genetics plays a vital role in the diagnosis and detection of ocular tumors. In uveal melanoma, monosomy 3 is the most common genetic alteration and somatic mutations of BAP1, a tumor suppressor gene, have been reported in nearly 50% of primary uveal melanomas. The retinoblastoma gene RB1 is the prototype tumor suppressor gene-mutations in RB1 alleles lead to inactivated RB protein and the development of retinoblastoma. Immunoglobulin heavy chain (IgH) or T-cell receptor (TCR) gene rearrangement is observed in B-cell or T-cell primary vitreoretinal lymphoma, respectively. Other factors related to the genetics of these three common malignancies in the eye are discussed and reviewed.