SWEPT SOURCE OCT EN-FACE IMAGING OF VITREOUS CAVITY REVEALS THE TOPOGRAPHIC RELATIONSHIP OF THE PREMACULAR BURSA, CLOQUET'S CANAL, PREVASCULAR VITREOUS FISSURES, LACUNAE AND CISTERNS [Meeting Abstract]
Near-infrared reflectance imaging of proliferative diabetic retinopathy [Meeting Abstract]
Purpose: Blood is one of the main absorbers in the near-infrared spectrum and therefore retinal vessels appear dark in near-infrared reflectance (NIR) images. Proliferative diabetic retinopathy (PDR) is characterized by the growth of abnormal vessels which also absorb light and appear dark against a lighter fundus background. We aim to study the usefulness of NIR imaging in the detection and follow-up of neovascular complexes (NVCs) in PDR.
Method(s): Retrospective study of 20 eyes of 17 patients with PDR who underwent NIR imaging with optical coherence tomography (OCT) using the Spectralis System as part of routine clinical examination. NVCs presence and activity was determined using clinical, tomographic and angiographic criteria.
Result(s): Twenty-seven NVCs were imaged, of which, 48% were neovascularization of the disc (NVD) and 52% were elsewhere (NVE). Mean patient follow-up was 3.7 years. Consecutive images were obtained from 3 to 5 time-points. All patients underwent laser treatment and 7 had additional intravitreal therapy. At baseline, NVCs were absent, present and active and present and inactive, respectively in 11%, 85% and 4% of cases. NIR identified active NVCs as hyporreflective irregular dark vessels originating from the retinal venules in NVE or from the disc in NVD. Associated hyperreflective fibrotic tissue was seen at baseline in 26%. NIR regression shown by reduced dark perfusion was observed in the 1 follow-up visit in 33% of cases and in 70% of cases in the 4 visit, consistent with various laser sessions. Progression with new vascular dark fronds was documented in about 40% scans in all time points. Four eyes developed a wolf's jaw configuration with vascular hyporreflective new vessels and hyperreflective tissue from extensive fibrosis. Fibrosis was more apparent in later images, reaching 77%. In a minority of cases (7%) the NVC was no longer seen in NIR, although was still identifiable on OCT over the NVC area.
Conclusion(s): NIR is a non-invasive imaging modality commonly performed alongside OCT and frequently overlooked which can be useful to evaluate NVCs in PDR. Blood is one of the main absorbers in the NIR spectrum and therefore 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
Outer Retinal Tubulation Associated With Chronic Retinal Detachment
LARGE RETINAL PIGMENT EPITHELIAL RIP ASSOCIATED WITH BULLOUS RETINAL AND CHOROIDAL DETACHMENT [Case Report]
PURPOSE/OBJECTIVE:To report a giant retinal pigment epithelium rip in a patient with a bullous retinal and choroidal detachment. METHODS:Case report with widefield imaging, fundus autofluorescence, and optical coherence tomography of the retina. RESULTS:This 62-year-old patient had a history of advanced glaucoma, trabeculectomy, blebitis, and endophthalmitis. He had cataract surgery 6 weeks before presentation. He was found to have a large bullous retinal and choroidal detachment with a large retinal pigment epithelium tear at the limit of the choroidal detachment. After vitrectomy for retinal detachment repair, the tear was observed to extend inferiorly at the margins of the choroidal detachment. CONCLUSION/CONCLUSIONS:This case report demonstrates that large retinal pigment epithelium rips can be found associated with large bullous choroidal and retinal detachments. These tears seem similar to tears that have been observed after trabeculectomy.
TOMOGRAPHIC RELATIONSHIPS BETWEEN RETINAL NEOVASCULARIZATION AND THE POSTERIOR VITREOUS IN PROLIFERATIVE DIABETIC RETINOPATHY
PURPOSE: To describe anatomical relationships of retinal neovascular complexes (NVCs) and the posterior vitreous in proliferative diabetic retinopathy using spectral domain optical coherence tomography. METHODS: Cross-sectional study. Neovascular complexes were imaged using spectral domain optical coherence tomography in 51 eyes of 37 patients. The relationship of NVCs to the posterior vitreous cortex and posterior vitreous spaces, such as the premacular bursa, prevascular vitreous fissures, and perimacular cisterns, was analyzed. RESULTS: In the 77 NVCs evaluated, 61 (79%) had grown along the outer surface of the posterior hyaloid face, and vitreoschisis was present in 37 (48%). The "wolf's jaw" configuration was present in 9% and resulted from NVC arising from the arcades and proliferating along the posterior hyaloid face. By contrast, NVCs that invaded the bursa originated from smaller venous tributaries more distant from the arcades. The premacular bursa and prevascular vitreous fissure/perimacular cistern were invaded infrequently, respectively, in 15% and 38% (P = 0.137). CONCLUSION: Tomographic analysis of diabetic NVCs showed that most NVCs arise and grow along the posterior hyaloid face and that vitreoschisis is more prevalent than what has been found in ultrasound studies. The wolf's jaw configuration does not seem to result from the invasion of the bursa, as previously suggested.
Biomechanical modeling of macular hole formation and development [Meeting Abstract]
Purpose: A macular hole (MH) is a pathological full thickness retinal defect in the macular region (MR). Interestingly, a MH always possesses a circular shape in the retinal plane. Present assumptions on MH etiology refer to tangential or anterior-posterior tensile forces at the foveal region. Using biomechanical models, we investigated the impact of biomechanical factors in macular region on the MH formation and its circular shape. Methods: 2D-and 3D-finite-element models of MR were developed based on optical coherence tomography (OCT) volume scans of a healthy eye. The models consist of two elastic layers: the internal limiting membrane (ILM: E=0.147MPa) and the retina (E=0.431MPa). Both materials were modeled as linearly elastic and incompressible. In the ILM in MR a small ellipsoidal slit was constructed as a precursor to a macular hole. In the 3D model, the axial ratio (minor d /major axis b, see Figure) of the initial constructed slit was determined assuming physiological intraocular pressure (IOP) range. In the 2D model, tangential and anterior-posterior tensile forces were applied to the intact ILM at specific angular vitreal attachments (shearing angle ranged 0degree-90degree). Maximal principal strains were computed, which are likely candidates of causing failure in the tissue and thus MH formation. Results: Under physiological IOP-conditions, the 2D model of MR without an initial slit shows high strains exactly in the area, where the MH formation is observed clinically. Using the 3D model further simulations under the same conditions show that an initial slit turns into an oval shape with a tendency to become round. When additional forces were considered in the attachment region of the vitreous it was observed that maximal principal strains in MR become larger with smaller shearing angle under predominant tangential forces. Tangential forces become greater than tensile forces hence being potentially riskier for MH progression. Conclusions: The IOP as single factor is not alone responsible for the circular formation of a MH from an initial slit. However, forces, especially tangential ones, transferred by the detaching vitreous result in high principal strains in MR. This aspect in combination with weakened tissue might lead to MH formation. Biomechanical modelling can be a useful tool for the investigation of MH etiology as well for the early MH diagnostics and the prediction of its progression
Clinical outcomes and antibiotic susceptibilities of Staphylococcus aureus endophthalmitis
PURPOSE: To compare the antibiotic susceptibilities and visual acuity (VA) outcomes in endophthalmitis caused by methicillin-resistant (MRSA) versus methicillin-sensitive S. aureus (MSSA). METHODS: The records of 34 cases of S. aureus endophthalmitis at The New York Eye and Ear Infirmary from Jan 1997 to June 2011 were reviewed. Antibiotic susceptibility profiles over time and VA at presentation and at 3, 6, and >/=12 months were recorded. S. aureus isolates were grouped based on oxacillin resistance. RESULTS: Of the 34 cases, 15 (44 %) were MRSA and 19 (56 %) MSSA. Median presenting VA was hand motions (logMAR 4.0) in both the MRSA and MSSA groups. There was no statistically significant difference in VA between the MRSA and MSSA groups at 3, 6, or >/=12 months. No MRSA isolates were resistant to vancomycin or gentamicin. While over 85 % of MRSA isolates tested for fourth-generation fluoroquinolones were resistant, just 10 % MSSA isolates tested were resistant. There was a trend suggesting an increase in the proportion of MRSA isolates compared to MSSA isolates over the course of the study period. CONCLUSIONS: There was no statistical difference in short- or long-term VA outcomes between the MRSA and MSSA groups at any time point. Resistance to fourth-generation fluoroquinolones was present in over 85 % of MRSA isolates, but just 10 % of MSSA isolates. An increasing proportion of MRSA amongst S. aureus isolates was noted over the course of the study period.
Intrabursal and Subhyaloid Hemorrhages in Valsalva Retinopathy
An Assessment of Vitreous Degeneration in Eyes with Vitreomacular Traction and Macular Holes
Purpose. To compare the stages of vitreous degeneration in patients with vitreomacular traction (VMT) and macular holes (MH). Methods. A retrospective study was performed analyzing stages of vitreous degeneration of eyes with VMT or MH using swept-source optical coherence tomography (SS-OCT) and spectral-domain optical coherence tomography (SD-OCT). An analogous review was performed on a control group of eyes with contralateral posterior vitreous detachments. Thirty-four eyes with VMT/MH and 39 control eyes were reviewed. Results. Twenty-seven VMT/MH eyes and 31 control eyes were included. Eyes with VMT/MH demonstrated significantly earlier stages of vitreous degeneration when compared to the control group (p = 0.048) despite significantly greater age (p = 0.032). Conclusions. Vitreoretinal interface disease is more often associated with a formed vitreous and an intact premacular bursa. This is contrary to previous assumptions implicating degeneration of vitreous as a precipitating factor of interface disease when in conjunction with abnormal vitreomacular separation.
Risk Alleles Associated with Neovascularization in a Pachychoroid Phenotype