BACILLARY LAYER DETACHMENT: MULTIMODAL IMAGING AND HISTOLOGIC EVIDENCE OF A NOVEL OPTICAL COHERENCE TOMOGRAPHY TERMINOLOGY
PURPOSE/OBJECTIVE:To clarify the histologic basis of bacillary layer detachment (BALAD) through a review of current literature and an analysis of retinal imaging. METHODS:We reviewed the literature for previous reports of BALAD. An analysis of retinal images was performed to support anatomic conclusions. RESULTS:A total of 164 unique patients with BALAD on optical coherence tomography (OCT) were identified from the published literature. Twenty-two underlying etiologies, all associated with subretinal exudation, were identified. Forty-one different OCT terminologies were found. The defining OCT feature of BALAD was a split at the level of the photoreceptor inner segment myoid creating a distinctive intraretinal cavity. Resolution of BALAD was followed by a rapid restoration of the ellipsoid zone. Histology of age-related macular degeneration eyes suggests that individual photoreceptors can shed inner segments. Further, detachment of the entire layer of inner segments is a common postmortem artefact. We propose that BALAD occurs when outwardly directed forces promoting attachment of photoreceptor outer segments to the retinal pigment epithelium exceed the tensile strength of the photoreceptor inner segment myoid. CONCLUSION/CONCLUSIONS:Our review serves to strengthen the OCT nomenclature "bacillary layer detachment", based on specific reflectance information obtained by OCT and previously published histologic observations.
Near-infrared reflectance imaging of neovascularization in proliferative diabetic retinopathy
BACKGROUND:Blood is one of the main absorbers in the near-infrared spectrum and thus retinal vessels appear dark in near-infrared reflectance (NIR) images. Proliferative diabetic retinopathy (PDR) is characterized by abnormal neovascularization which also absorbs light and appears dark against a lighter fundus background. We analyzed neovascularization in PDR using NIR imaging, by observing changes in the neovascular complexes (NVCs) contrast and reflectivity over time. METHODS:Retrospective case series of 20 eyes of 17 patients with PDR who underwent NIR imaging with optical coherence tomography (OCT) using the Spectralis System. NVCs presence and activity was determined using clinical, tomographic and angiographic criteria. At baseline, all NVCs were qualitatively graded in the NIR image into 3 groups (absent, present and inactive and present and active) and their evolution over time was registered as progression, regression or same status. RESULTS:Twenty-seven NVCs were imaged, of which, 52% were neovascularization of the disc (NVD) and 48% were elsewhere (NVE). Consecutive NIR images were obtained from baseline to up to 5 time-points with a mean follow-up of 3.2â€‰Â±â€‰1.7Â years. All eyes underwent laser treatment and 30% had additional intravitreal therapy. Using NIR imaging, NVCs were classified at baseline as absent, present and inactive and present and active, respectively in 11, 4 and 85% of cases. NIR identified active neovascularization as hyporeflective irregular dark vessels originating from the retinal venules in NVE or from the disc in NVD. In all groups during follow-up, progression was identified as the development of new vascular hyporeflective dark fronds while regression was shown by reduced dark perfusion. Five eyes developed a wolf's jaw configuration with vascular hyporeflective new vessels and hyperreflective tissue from extensive fibrosis. Fibrosis was more apparent in later images, reaching 86%. In 3 cases (11%), the NVC was no longer seen in NIR, although was still identifiable on OCT over the NVC area. CONCLUSIONS:NIR is a non-invasive imaging modality commonly performed alongside OCT and frequently overlooked which can be useful to evaluate NVCs in PDR. Changes in NVC contrast and reflectivity due to blood perfusion can help in the detection and monitoring of diabetic proliferative disease and aid clinicians in daily practice.
The Vitreous: Making the Invisible Visible
Intravitreous Cutaneous Metastatic Melanoma in the Era of Checkpoint Inhibition: Unmasking and Masquerading
PURPOSE/OBJECTIVE:Cutaneous melanoma metastatic to the vitreous is very rare. This study investigated the clinical findings, treatment, and outcome of patients with metastatic cutaneous melanoma to the vitreous. Most patients received checkpoint inhibition for the treatment of systemic disease, and the significance of this was explored. DESIGN/METHODS:Multicenter, retrospective cohort study. PARTICIPANTS/METHODS:Fourteen eyes of 11 patients with metastatic cutaneous melanoma to the vitreous. METHODS:Clinical records, including fundus photography and ultrasound results, were reviewed retrospectively, and relevant data were recorded for each patient eye. MAIN OUTCOME MEASURES/METHODS:Clinical features at presentation, ophthalmic and systemic treatments, and outcomes. RESULTS:The median age at presentation of ophthalmic disease was 66 years (range, 23-88 years), and the median follow-up from diagnosis of ophthalmic disease was 23 months. Ten of 11 patients were treated with immune checkpoint inhibition at some point in the treatment course. The median time from starting immunotherapy to ocular symptoms was 17 months (range, 4.5-38 months). Half of eyes demonstrated amelanotic vitreous debris. Five eyes demonstrated elevated intraocular pressure, and 4 eyes demonstrated a retinal detachment. Six patients showed metastatic disease in the central nervous system. Ophthalmic treatment included external beam radiation (30-40 Gy) in 6 eyes, intravitreous melphalan (10-20 Î¼g) in 4 eyes, enucleation of 1 eye, and local observation while receiving systemic treatment in 2 eyes. Three eyes received intravitreous bevacizumab for neovascularization. The final Snellen visual acuity ranged from 20/20 to no light perception. CONCLUSIONS:The differential diagnosis of vitreous debris in the context of metastatic cutaneous melanoma includes intravitreal metastasis, and this seems to be particularly apparent during this era of treatment with checkpoint inhibition. External beam radiation, intravitreous melphalan, and systemic checkpoint inhibition can be used in the treatment of ophthalmic disease. Neovascular glaucoma and retinal detachments may occur, and most eyes show poor visual potential. Approximately one quarter of patients demonstrated ocular disease that preceded central nervous system metastasis. Patients with visual symptoms or vitreous debris in the context of metastatic cutaneous melanoma would benefit from evaluation by an ophthalmic oncologist.
OCT En Face Analysis of the Posterior Vitreous Reveals Topographic Relationships among Premacular Bursa, Prevascular Fissures, and Cisterns
PURPOSE/OBJECTIVE:To characterize the topographic relationships among vitreous structures, including the premacular bursa, prevascular vitreous fissures, cisterns, and lacunae, in healthy participants using en face and cross-sectional swept-source (SS) OCT. DESIGN/METHODS:Prospective, comparative study. PARTICIPANTS/METHODS:Sixty eyes of 60 healthy participants (age range, 4-35 years). Eyes of individuals younger than 20 years (nÂ = 29) were compared with eyes of individuals 20 years of age or older (nÂ = 31). METHODS:From each study eye, 12Â Ã— 12-mm SS OCT volume scans comprising 1024Â Ã— 1024 A-scans centered at the fovea were acquired. MAIN OUTCOME MEASURES/METHODS:En face and cross-sectional data were analyzed to characterize topographic relationships between hyperreflective spaces anterior to the vitreoretinal interface. RESULTS:Prevascular vitreous fissures are an almost universal feature of human eyes. Cisterns became more prevalent over the course of the first 20 years (rÂ = 0.49; PÂ = 0.002). In 97% of eyes in individuals older than 20 years, en face and cross-sectional SS OCT showed the premacular bursa and prepapillary gap merge at a distance superior to the optic nerve and then follow a superonasal course anteriorly. However, only 69% of individuals younger than 20 years demonstrated such a connection (PÂ = 0.01). A close topographic relationship of vitreous fissures and cisterns to the underlying vasculature of the posterior pole was visible on en face projections. En face imaging readily distinguished these spaces. Degenerative, eyewall-parallel fissure planes and their course were described for the first time in a 3-dimensional manner. The fissure planes were rare in younger eyes (12%) and significantly more common in older eyes (42%; P < 0.001). CONCLUSIONS:En face SS OCT demonstrated that (1) premacular bursa and Cloquet's canal are not connected in younger patients, but are connected in older patients; (2) prevascular vitreous fissures overly the retinal vessels; and (3) cisterns are continuous with prevascular fissures.
Optical Coherence Tomography Angiography Features of Neovascularization in Proliferative Diabetic Retinopathy [Case Report]
Purpose/UNASSIGNED:To describe features of neovascularization in proliferative diabetic retinopathy (PDR) using optical coherence tomography angiography (OCTA). Methods/UNASSIGNED:A retrospective case series was performed in 23 eyes from 21 patients who underwent OCTA of neovascular complexes (NVCs) due to PDR. Eyes were imaged with the DRI Triton swept-source OCTA, Avanti RTVue XR or Cirrus HD-OCT 5000 as part of routine clinical examination. Segmentation was adjusted to include vasculature between the vitreous cavity and the internal limiting membrane (ILM). The presence of NVCs was confirmed by clinical examination and multimodal imaging such as color or red-free fundus photography, fluorescein angiography, multicolor imaging or near-infrared reflectance. Results/UNASSIGNED:Thirty-five NVCs were imaged, of which, 34% were neovascularization of the disc (NVD) and 66% were neovascularization elsewhere (NVE). On structural OCT B-scans, NVE appeared as medium to highly reflective tissue that breached the ILM, while NVD showed highly reflective tissue protruding from the disc in a sea fan configuration. Flow signal was seen on OCTA in all cases of NVE and in 67% of NVD lesions. Areas with minimal or absent retinal flow signal identified retinal nonperfusion areas and were found adjacent to 87% of NVE. Intraretinal microvascular abnormalities (IRMAs) were noted next to 70% of NVE. Absent flow signal was seen in 4 NVD cases showing posterior shadowing and were considered inactive. Conclusion/UNASSIGNED:OCTA appears useful for imaging NVCs, IRMAs, and retinal nonperfusion areas in eyes with diabetic retinopathy. This imaging modality enables noninvasive screening and monitoring of PDR and can obviate the need for additional testing in certain clinical settings.
Choroidal Effusion after Laser Peripheral Iridotomy
A Two Forceps Technique For Approaching Tractional Diabetic Membranes
BACKGROUND AND OBJECTIVE/OBJECTIVE:To describe a two-forceps bimanual approach for complex diabetic detachments. PATIENTS AND METHODS/METHODS:Curved scissors were used to create a zone of decreased resistance within a thick fibrovascular membrane in a previously vitrectomized patient. Using two forceps, the linear defect was propagated into the periphery in a direction tangential to the retina. The tissue was repeatedly regrasped at the leading edge of the propagating tear, allowing for progressive separation of the hyaloid from the retinal surface. RESULTS:Separation of the diabetic membrane and hyaloid from the retinal surface in a previously vitrectomized patient. CONCLUSION/CONCLUSIONS:The authors describe a two-forceps approach for dense fibrovascular proliferation in the setting of persistently attached cortical vitreous that may be employed in cases of severe diabetic retinopathy with traction and fibrovascular membranes, even after previous vitrectomy. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:e176-e178.].
In vivo imaging of the fibrillar architecture of the posterior vitreous and its relationship to the premacular bursa, Cloquet's canal, prevascular vitreous fissures, and cisterns
PURPOSE/OBJECTIVE:To describe the fibrillar architecture of the posterior cortical vitreous and identify variations across eyes of different axial lengths in vivo. METHODS:Sixty-four eyes of 32 subjects were examined with swept-source optical coherence tomography (SS-OCT). Grading of vitreous degeneration, presence of vitreous cisterns/lacunae, posterior hyaloid status, directionality of vitreous fibers and their relations to vitreous spaces, and lamellar reflectivity of the posterior vitreous were assessed. RESULTS:A consistent pattern of fibrillar organization was discovered. Eyewall parallel fibers formed a dense meshwork over the retinal surface and fibers oriented in a perpendicular fashion to this meshwork were found to envelop the various vitreous spaces, intersecting at variable angles of insertion to the eyewall parallel fibers. Lamellar reflectivity suggestive of splitting of the cortical fibrillar meshwork was detected in 27 eyes (42%) with 56% of these eyes demonstrating perpendicularly oriented intersecting fibers. Fifty-six percent of eyes with lamellar reflectivity had an axial length >â€‰25Â mm. CONCLUSION/CONCLUSIONS:SS-OCT imaging revealed fibrillar organization of the posterior vitreous. Eye wall parallel hyperreflectivity of cortical vitreous was a universal finding. This pattern is suggestive of a splitting of cortical vitreous tissue and may represent a precursor to vitreoschisis. Perpendicular fibers appear to be important constituents of the walls of the various liquid vitreous spaces.
Proliferative diabetic retinopathy imaged by near-infrared reflectance