A, Six radial scans centered on the fovea with a 30° width. B, Single line scan centered on the fovea with a 7° tilt and a 30° width that traverses the optic disc and fovea.
A, No posterior vitreous detachment (PVD), with complete attachment of the posterior vitreous cortex (PVC) (arrowheads) to the perifoveal area, fovea, and optic disc. The premacular bursa (asterisk) is well visualized within the posterior vitreous. B, Incomplete PVD with separation of the PVC (arrowheads) at the temporal perifoveal area. There is persistent vitreomacular adhesion and residual attachment of the PVC at the nasal perifoveal area and optic disc. The premacular bursa (asterisk) is well visualized within the posterior vitreous. C, Incomplete PVD with separation of the PVC (arrowheads) over the nasal and temporal perifoveal areas. There is persistent vitreomacular adhesion and persistent attachment at the optic disc. The premacular bursa (asterisk) is well visualized within the posterior vitreous. D, Incomplete PVD with shallow separation of the PVC (arrowheads) over the perifoveal areas and fovea but persistent attachment at the optic disc. The posterior wall of the premacular bursa (asterisk) is still intact. E, Incomplete PVD with separation of the PVC (arrowheads) over the perifoveal areas and fovea but persistent attachment at the optic disc. The PVC has retracted further into the vitreous cavity. The posterior wall of the premacular bursa (asterisk) is still intact. F, Incomplete PVD with separation of the PVC (arrowheads) at the perifoveal areas and fovea but residual attachment at the optic disc. There is disruption of the posterior wall of the premacular bursa (asterisk). G, Incomplete PVD with detachment of the PVC (arrowheads) at the perifoveal areas and fovea but residual attachment at the optic disc. There is disruption of the posterior wall of the premacular bursa (asterisk). Vitreous opacities appear in the vitreous gel (circles). This patient was symptomatic for vitreous floaters. H, Complete PVD with the appearance of an optically empty peripheral vitreous cavity superior to the retinal layers in all areas, including the fovea and optic disc. The PVC (arrowhead) and vitreous with vitreoschitic fissure planes (double-headed arrow) and lacunae (asterisk) are seen in the vitreous cavity. I, Incomplete PVD with separation of the PVC (white arrowheads) over the entire macula, but persistent attachment at the optic disc. A macular hole and operculum (black arrowhead) are present on the PVC at the bottom of the premacular bursa. J, Incomplete PVD with vitreomacular traction, with degradation and doubling of the vitreous interface (arrowheads) due to saccadic eye movement and consequent movement of the PVC.
Pang CE, Freund KB, Engelbert M. Enhanced Vitreous Imaging Technique With Spectral-Domain Optical Coherence Tomography for Evaluation of Posterior Vitreous Detachment. JAMA Ophthalmol. 2014;132(9):1148-1150. doi:10.1001/jamaophthalmol.2014.1037
Vitreous degeneration, gradual separation of the posterior vitreous cortex (PVC), and eventual development of posterior vitreous detachment (PVD) are important in vitreoretinal interface diseases. However, determination of the stages of PVD with biomicroscopy or ultrasonography is not sufficiently sensitive and specific.1,2 Since the advent of spectral-domain (SD) optical coherence tomography (OCT), PVD detection has improved and new concepts regarding the evolution of PVD have emerged.2,3 However, SD-OCT remains underused, possibly owing to general low awareness of its potential to image the vitreoretinal interface and the vitreous itself.4,5 We aim to demonstrate the usefulness of an enhanced vitreous imaging (EVI) OCT technique in evaluating PVD.
Six radial scans with a scan width of 30° centered at the fovea were obtained on the Heidelberg Spectralis (Heidelberg Engineering), in addition to a single 30° line scan taken with a 7° tilt, traversing both the optic disc and fovea simultaneously (Figure 1). All scans were the product of 45 to 70 averaging images by automatic real-time function, pulling back to focus on the vitreous. The retinal layers were positioned inferiorly on the image screen to obtain a maximum imaging depth of 1.5 mm into the vitreous, and the image brightness was increased slightly to improve visualization of the vitreous.
Using EVI-OCT, we were able to demonstrate various stages of PVD. In posterior vitreous attachment, there is persistent attachment of the PVC over the entire posterior pole including the fovea and optic disc (Figure 2A). Incomplete PVD may begin with detachment of the PVC at perifoveal areas but persistent attachment over the fovea and persistent attachment at the optic disc (Figure 2B and C). With gradual release of the persistent attachment over the fovea, there is progression of the PVD, although it is incomplete due to persistent attachment at the optic disc (Figure 2D and E). Disruption of the posterior wall of the premacular bursa4 was well demonstrated with EVI-OCT (Figure 2F and G). The EVI-OCT displayed vitreous opacities and laminar structures of the posterior vitreous in the context of vitreoschisis (Figure 2G).6 Complete PVD could be appreciated as an optically empty vitreous cavity seen central to the retinal layers, and often an intact PVC was seen (Figure 2H). During the development of perifoveal PVD, strong vitreomacular adhesion may lead to macular hole formation with an operculum or vitreomacular traction syndrome (Figure 2I and J).
Studies using SD-OCT for the posterior vitreous have previously been limited to vertical and horizontal scans on the Cirrus OCT machine.4,5 This article illustrates the use of radial scans on the Spectralis SD-OCT. Inclusion of both the optic disc and the fovea is critical to unequivocally stage posterior vitreous separation. With EVI-OCT, we were able to achieve adequate image resolution and depth into the vitreous by using built-in functions including defocus, scan tilt, and automatic real-time function. In our experience, the “sweet spot” for automatic real-time function lies between 45 and 65 scans, as small saccades during the lengthy scanning process lead to vitreous movement and consequent apparent doubling of the PVC (Figure 2J). This problem is obviated on swept-source OCT machines owing to the much faster image acquisition.5 The use of EVI-OCT may enhance patient counseling by demonstrating visible vitreous floaters and PVC separation to symptomatic patients, improving patient understanding and promoting greater patient satisfaction. Keeping in mind that only the posterior vitreous is visualized, supplementing with B-scan ultrasonography may be prudent to establish peripheral vitreous face status.
In summary, EVI-OCT enables more precise characterization of the PVD process, which is essential in this era of pharmacologic vitreolysis. This article aims to heighten awareness of this vitreous imaging technique and encourage its use in the appropriate clinical setting.
Corresponding Author: Michael Engelbert, MD, PhD, Vitreous Retina Macula Consultants of New York, 460 Park Ave, Fifth Floor, New York, NY 10022 (email@example.com).
Published Online: July 10, 2014. doi:10.1001/jamaophthalmol.2014.1037.
Author Contributions: Dr Engelbert had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: All authors.
Acquisition, analysis, or interpretation of data: All authors.
Drafting of the manuscript: All authors.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Pang, Engelbert.
Administrative, technical, or material support: Pang.
Study supervision: Freund, Engelbert.
Conflict of Interest Disclosures: Dr Freund is a consultant for Heidelberg Engineering, Genentech, Regeneron, and Bayer. No other disclosures were reported.
Funding/Support: This work was supported by the Macula Foundation, Inc.
Role of the Sponsor: The Macula Foundation, Inc had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.