Effect of Fiber Reinforcement on the Flexural Strength of the Transitional Implant-Supported Fixed Dental Prosthesis.

PURPOSE: The aim of this in vitro study was to assess the efficacy of fiber reinforcement to enhance flexural strength of the transitional implant-supported fixed dental prosthesis (TISFDP). MATERIALS AND METHODS: One hundred and forty denture acrylic resin plates (64 mm × 12 mm × 5 mm) with two 7 mm diameter holes were fabricated using heat-polymerized type (Lucitone 199) and CAD-CAM prepolymerized type (AvaDent) materials to simulate a chair-side reconstruction of the TISFDP. Specimens were divided into 7 groups (n = 10) according to the airborne-particle abrasion of titanium cylinder (Straumann) surface and locations of fiber reinforcement ribbons (Ribbond-ULTRA). No cylinder surface abrasion and no fiber added acrylate specimens were used as the controls. The prosthetic screws were hand-tightened on a custom fixture with analogs. Specimen hole and cylinder were joined using a 50:50 mixture of chemically polymerized resin (QYK-SET; Holmes Dental) and repair resin (Dentsply Sirona). Ten acrylate specimens with no holes were fabricated from each tested material and assigned as positive controls. A modified four-point bending test (ASTM standard-D6272) was conducted using a universal testing machine and a custom fixture with a crosshead speed 1 mm/min. The maximum failure loads were recorded. Data were statistically analyzed using 2-way ANOVA and the Tukey tests at α = 0.05. RESULTS: The flexural strength values ranged from 55.4 ±8.3 to 140.9 ±15.4 MPa. The flexural strength decreased significantly when fiber was attached on the titanium cylinder surface (p < 0.05). There were no statistically significant differences in flexural strength values between specimens with and without titanium cylinder surface abrasion (p > 0.05). Statistically significant improvement in flexural strength was observed in specimens with fibers attached around the specimen holes (p < 0.05) buccally and lingually. The obtained values were not statistically significantly different from the positive controls (p > 0.05). Some fixation screw fractures were observed before catastrophic failure of specimens during testing. CONCLUSIONS: Fiber reinforcement significantly improved the flexural strength of denture acrylic resins only if placed around the specimen holes on the tension side at the site of initiation of crack propagation. Even when the specimens underwent catastrophic failure, the segments remained attached to each other with the attached fibers.

SAUSAGING AND BULBOSITIES OF THE CHOROIDAL VEINS IN CENTRAL SEROUS CHORIORETINOPATHY.

PURPOSE: To evaluate the caliber of the choroidal veins in central serous chorioretinopathy, a disease proposed to be associated with overloading of choroidal venous outflow. METHODS: Widefield indocyanine green angiograms of eyes with central serous chorioretinopathy were graded for sausaging defined as three or more contiguous fusiform dilations that vary by at least 50% from the narrowest to largest diameters. A bulbosity was defined as a focal 2X dilation of a blood vessel as compared with the diameter of the surrounding host vessel. The data underwent statistical analysis including the use of generalized estimating equations. RESULTS: There were 73 eyes of 41 patients with a mean age of 53.5 years. Sausaging of vessels was seen in a mean and median of three quadrants per eye. Using generalized estimating equations, the only significant risk factor for sausaging was the use of corticosteroids. The two significant predictors of subfoveal choroidal thickness using generalized estimating equations were age ( P = 0.021) and proportion of quadrants involved by sausaging ( P < 0.001). The decrease in choroidal thickness per year of age was estimated to be 3.7 µ m, while the increase with four quadrant involvement with sausaging was estimated to be 236 µ m. There were a total of 39 bulbosities in 26 eyes (35.6%), preferentially involving intervortex venous anastomoses. CONCLUSION: Variations in the venous caliber are very common in eyes with central serous chorioretinopathy and seems to be associated with pathophysiologic alterations related to increased pressure within and remodeling of the larger choroidal veins. This may lead to overloading of the choriocapillaris with leakage as one manifestation.

MULTIPLE EVANESCENT WHITE DOT SYNDROME WITH SUBRETINAL DEPOSITS.

PURPOSE: To describe the multimodal imaging findings of transient subretinal deposits occurring in multiple evanescent white dot syndrome (MEWDS). METHODS: The multimodal imaging characteristics of transient subretinal deposits occurring in MEWDS were investigated with ultra-widefield color and fundus autofluorescence, cross-sectional and en-face optical coherence tomography (OCT), en face OCT-angiography, and quantitative autofluorescence. RESULTS: A 28-year-old woman presented with photopsia and temporal visual field loss in her right eye. Her best-corrected visual acuity was 20/20 in her right eye and 20/25 in her left eye. Funduscopic examination showed characteristic peripapillary hyperautofluorescent white dots of MEWDS corresponding to ellipsoid zone disruption on OCT. These lesions became confluent throughout the posterior fundus over the next 4 weeks. As the patient's symptoms were resolving, a second type of transient hyperautofluorescent lesion was noted which corresponded to hyperreflective subretinal deposits on cross-sectional and en face structural OCT. These subretinal deposits were most evident at 10-week follow-up and had nearly resolved at 14-week follow-up. Quantitative autofluorescence showed that, unlike the acute MEWDS lesions, the hyperautoflurescence of the subretinal deposits persisted after photobleaching. At multiple time points over 14 weeks of follow-up, OCT angiography showed no evidence of retinal or choroidal flow abnormalities. CONCLUSION: Transient subretinal deposits may develop during MEWDS in areas of previous diffuse outer retinal disruption. As these deposits remain hyperautoflurescent on quantitative autofluorescence after photobleaching, they may represent accumulations of debris originating from damaged photoreceptor outer segments.

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY OF CHORIORETINAL LESIONS DUE TO IDIOPATHIC MULTIFOCAL CHOROIDITIS.

PURPOSE: To evaluate the spectrum of macular chorioretinal lesions occurring in idiopathic multifocal choroiditis using optical coherence tomography angiography (OCTA) to evaluate those showing neovascular flow. METHODS: This was a descriptive, retrospective study of 18 eyes of 14 patients with multifocal choroiditis. Macular lesions were characterized as subretinal pigment epithelium, subretinal, or mixed and evaluated during active and presumed inactive states of multifocal choroiditis. Correlations between structural optical coherence tomography and OCTA were performed. In select cases, correlations between OCTA, fluorescein angiography, and fundus autofluorescence were evaluated. In 5 eyes, quantitative measurements of neovascular lesions were compared at baseline and following intravitreal anti-vascular endothelial growth factor therapy. RESULTS: Mean patient age was 48 years (SD: 13.8; 86% women). Optical coherence tomography angiography flow signatures consistent with neovascularization were identified in 83% of eyes, including in 0% of subretinal pigment epithelium, 91% of subretinal, and 100% of mixed lesions. Lesions that did not demonstrate definitive signs of fluorescein angiography leakage were frequently found to have neovascularization using OCTA. There was no change in quantitative measurements of neovascular lesions after anti-vascular endothelial growth factor therapy (all tested variables P > 0.05). CONCLUSION: Optical coherence tomography angiography may be a useful imaging modality for understanding the pathophysiology of multifocal choroiditis and monitoring its clinical course.

ASSOCIATION BETWEEN NEEDLE SIZE, POSTINJECTION REFLUX, AND INTRAOCULAR PRESSURE SPIKES AFTER INTRAVITREAL INJECTIONS.

PURPOSE: To compare the effect of 30-gauge versus 32-gauge needle size on postinjection reflux and immediate postinjection intraocular pressure (IOP(immed_post)) spikes in eyes injected with anti-vascular endothelial growth factor agents. METHODS: This was a prospective interventional case series of 65 eyes of 54 consecutive patients in a clinical practice setting who received intravitreal anti-vascular endothelial growth factor therapy. All eyes had preinjection IOP, IOP(immed_post), postinjection reflux, and axial lengths recorded. RESULTS: There was a higher incidence of postinjection reflux in eyes injected with 30-gauge (53%) compared with those injected with 32-gauge (13%, P = 0.0007). Among 34 eyes injected with 30-gauge, 16 eyes without appreciable postinjection reflux had mean IOP(immed_post) of 44.3 ± 7.48 mmHg and mean IOP(immed_post) elevation of 29.6 ± 2.10 mmHg, which was significantly higher than the 18 eyes with reflux (mean IOP(immed_post) of 18.8 ± 7.15 mmHg and mean IOP(immed_post) elevation of 4.5 ± 1.74 mmHg, P < 0.0001). Among 31 eyes injected with 32-gauge, 27 eyes without appreciable postinjection reflux had mean IOP(immed_post) of 44.4 ± 10.82 mmHg and mean IOP(immed_post) elevation of 29.5 ± 1.99 mmHg, which was significantly higher than the 4 eyes with reflux (mean IOP(immed_post) of 21.3 ± 8.54 mmHg and mean IOP(immed_post) elevation of 9.5 ± 4.05 mmHg, P < 0.001). The differences in reflux and IOP between the two groups were unrelated to axial lengths (P = 0.451). CONCLUSION: Eyes receiving injections with 32-gauge needles had a lower incidence of postinjection reflux and higher mean IOP immediately after injection.

Adaptive optics imaging of cone mosaic abnormalities in acute macular neuroretinopathy.

BACKGROUND AND OBJECTIVE: To assess the cone photoreceptor mosaic in acute macular neuroretinopathy (AMN) using adaptive optics (AO) imaging. PATIENTS AND METHODS: Four patients with AMN were evaluated retrospectively by near-infrared reflectance (IR) confocal scanning laser ophthalmoscopy (SLO), spectral-domain optical coherence tomography (SD-OCT), and a flood-illuminated retinal AO camera. Microperimetry was performed in one patient. RESULTS: The cone photoreceptor density was decreased at the level of the AMN lesions. The cone mosaic disruption appeared heterogeneous and more widespread than the lesion detected in the IR-SLO and SD-OCT images. The areas of cone loss correlated with SD-OCT and microperimetry. After resolution of the AMN lesion on IR-SLO, there was incomplete recovery of the cone photoreceptor mosaic. CONCLUSION: Cone photoreceptor damage and reconstitution were documented in vivo at the cellular level in AMN using AO imaging. AO imaging appeared more sensitive than combined IR-SLO and SD-OCT to detect and follow photoreceptor damage in patients with AMN.

Fundus autofluorescence and photoreceptor bleaching in multiple evanescent white dot syndrome.

The authors present three cases of multiple evanescent white dot syndrome (MEWDS) with characteristic fundus autofluorescence (FAF) findings, including one patient without any visible white dots on funduscopic examination and another with many more hyperautofluorescent lesions than seen ophthalmoscopically. Additionally, the findings support an alternative mechanism for the hyperautofluorescent lesions in MEWDS, whereby photoreceptor loss causes unmasking of normal underlying retinal pigment epithelium autofluorescence. This hypothesis is demonstrated in two cases by optical coherence tomography showing clear ellipsoid zone attenuation with registration to hyperautofluorescent lesions. It is further supported in two cases by photoreceptor bleaching in successive FAF images captured in the same session leading to diminished autofluorescence intensity of the characteristic dots.

Paracentral acute middle maculopathy: a new variant of acute macular neuroretinopathy associated with retinal capillary ischemia.

IMPORTANCE: With the advent of more sophisticated imaging systems, such as spectral domain optical coherence tomography (SD-OCT), disruption of the inner segment/outer segment (IS/OS) band, and thinning of the outer nuclear layer (ONL) have been identified in association with acute macular neuroretinopathy (AMN). OBJECTIVES: To characterize a new SD-OCT presentation of AMN as a paracentral acute middle maculopathy and to describe multimodal imaging findings that implicate an underlying pathogenesis related to retinal capillary ischemia. DESIGN, SETTING, AND PARTICIPANTS: Retrospective observational case series (January 1, 2012, to January 1, 2013) reviewing clinical and imaging data from 9 patients (11 eyes) with AMN at 6 tertiary referral centers. Lesions were classified as type 1 or 2 in relation to the SD-OCT location of the lesion above (type 1) or below (type 2) the outer plexiform layer (OPL) at 6 tertiary referral centers. RESULTS: Of the 9 patients, 5 were female and 4 were male (mean age, 47.6 years; range, 21-65 years). All patients presented with an acute paracentral scotoma and demonstrated a classic dark gray paracentral lesion with near-infrared imaging. Visual acuity ranged from 20/15 to 20/30. Six eyes (5 patients) had type 1 SD-OCT lesions, also referred to as paracentral acute middle maculopathy, and 5 eyes (4 patients) had type 2 SD-OCT lesions. Although type 1 lesions lead to inner nuclear layer (INL) thinning, type 2 lesions resulted in ONL thinning. Type 2 lesions were always associated with significant outer macular defects, including disruption of the inner segment/outer segment and outer segment/retinal pigment epithelium bands, whereas type 1 lesions spared the outer macula. CONCLUSIONS AND RELEVANCE: Paracentral acute middle maculopathy may represent a novel variant of AMN that affects the middle layers of the macula above the OPL as diagnosed with SD-OCT imaging. Two types of AMN lesions may be seen with SD-OCT occurring above and below the OPL. Type 1 refers to hyperreflective bands in the OPL/INL region with subsequent INL thinning. Type 2 is hyperreflective bands in the OPL/ONL region with subsequent ONL thinning. Type 2 lesions may be associated with concomitant defects of the inner segment/outer segment layer. We propose that each of these lesions may be explained by occlusion of either the superficial capillary plexus (type 1) or deep capillary plexus (type 2) located in the innermost and outermost portion of the INL, respectively, immediately adjacent to each corresponding lesion type.

Visual and anatomical outcomes of intravitreal aflibercept in eyes with persistent subfoveal fluid despite previous treatments with ranibizumab in patients with neovascular age-related macular degeneration.

PURPOSE: To assess the efficacy of intravitreal aflibercept (2.0 mg) in patients with treatment-resistant neovascular age-related macular degeneration. METHODS: Retrospective analysis of eyes treated with aflibercept with persistent subretinal and/or intraretinal fluid despite previous treatments with intravitreal ranibizumab (0.5 mg). All patients were switched to intravitreal aflibercept (2.0 mg) and analyzed after 3 consecutive injections and after 6 months of treatment. Main outcome measures included change in visual acuity, central foveal thickness, and the height and diameter of the pigment epithelial detachment on the subfoveal scan on optical coherence tomography. RESULTS: Thirty-four eyes of 33 patients were analyzed. Mean duration of symptoms and average number of previous injections with anti-vascular endothelial growth factor agents was 44.7 ± 29.8 months (interquartile range [IQR] 24-76 months) and 28.6 ± 20.1 (IQR 10-47), respectively. At the 6-month follow-up, mean visual acuity and central foveal thickness improved significantly from 20/75 (logarithm of minimum angle of resolution 0.57 ± 0.36; IQR 0.30-1.0) and 416 ± 217 µm (IQR 263-487 µm) at baseline to 20/60 (logarithm of minimum angle of resolution 0.47 ± 0.32; IQR 0.30-0.60) (P = 0.004) and 248 ± 171 µm (IQR 235-419 µm) (P < 0.001), respectively. Maximum pigment epithelial detachment height improved significantly from 260 ± 162 µm (IQR 129-368 µm) to 214 ± 142 µm (IQR 111-305 µm) (P < 0.001) and PED diameter decreased significantly from 3,265 ± 1,622 µm (IQR 2,353-4,555 µm) to 2,949 ± 1,653 µm (IQR 1,721-4,484 µm) (P = 0.04). CONCLUSION: Intravitreal injections of aflibercept resulted in a significant improvement in visual and anatomical outcomes in eyes with persistent subfoveal fluid despite previous treatment with ranibizumab.

The "pitchfork sign" a distinctive optical coherence tomography finding in inflammatory choroidal neovascularization.

PURPOSE: To report four examples of a novel optical coherence tomography finding, which appears to be characteristic of inflammatory choroidal neovascularization. METHODS: Retrospective observational case series. RESULTS: Four eyes of four patients were diagnosed clinically with inflammatory choroidal neovascularization and underwent optical coherence tomography. In each case, imaging revealed multiple, distinctive finger-like projections extending from the area of active choroidal neovascularization into the outer retina-the "pitchfork sign"--a finding not typically seen in Type 2 neovascularization due to other etiologies. CONCLUSION: The pitchfork sign may help distinguish inflammatory choroidal neovascularization from other causes of Type 2 neovascularization.

Idiopathic polypoidal choroidal vasculopathy (IPCV). 1990.

Eleven patients, 40 to 71 years old, had a choroidal vasculopathy that led to hemorrhagic and exudative macular degeneration. The patients had peculiar polypoidal, subretinal, vascular lesions associated with serous and hemorrhagic detachments of the retinal pigment epithelium. This macular disorder, which we have named idiopathic polypoidal choroidal vasculopathy (IPCV), appears to represent a distinct entity that differs clinically and demograph-ically from age-related macular degeneration (AMD) and other macular diseases associated with subretinal neovascularization. Recognition of this condition is important because it may have specific risk factors, natural course, and management considerations that differ from those of age-related macular degeneration

Digital indocyanine green videoangiography and choroidal neovascularization. 1992.

This report describes a new system for digital indocyanine green videoangiography (ICGV) that provides enhanced imaging of the choroidal circulation. This newly assembled system was used to study a consecutive series of 129 patients with exudative age-related macular degeneration (AMD), and ill-defined or occult choroidal neovascularization (CNV). Overall, 39% of the patients in this study with occult CNV could be reclassified as having well-delineated or so-called classic CNV by virtue of the additional findings provided by ICGV. In this series, ICGV was particularly useful in identifying occult CNV in eyes with a large, serous pigment epithelial detachment (PED) and in eyes with recurrent CNV after previous laser photocoagulation treatment. Some of these patients were selected for laser photocoagulation of the abnormal choroidal vessels in order to evaluate the feasibility of this form of treatment on the basis of combined clinical, fluorescein angiographic, and ICGV findings. The results of this study suggest that ICGV is an important adjunct in the evaluation, classification, and laser treatment of patients with occult CNV secondary to AMD.

Retinal angiomatous proliferation in age­related macular degeneration. 2001.

BACKGROUND: It is known that choroidal neovascularization (CNV) in age-related macular degeneration (ARMD) may erode through the retinal pigment epithelium, infiltrate the neurosensory retina, and communicate with the retinal circulation in what has been referred to as a retinal­choroidal anastomosis (RCA). This is extremely common in the end stage of disciform disease. In recent years, the reverse also seems to be possible, as angiomatous proliferation originates from the retina and extends posteriorly into the subretinal space, eventually communicating in some cases with choroidal new vessels. This form of neovascular ARMD, termed retinal angiomatous proliferation (RAP) in this article, can be confused with CNV. PURPOSE: The purpose of this article is 1) to review the clinical and angiographic characteristics of a series of patients with RAP and 2) to propose a theoretical sequence of events that accounts for the neovascularized process. METHODS: In this retrospective clinical and angiographic analysis, 143 eyes with RAP (108 patients) were reviewed and classified based on their vasogenic nature and course. Clinical biomicroscopic examination, fluorescein angiography, and indocyanine green angiography were used to evaluate patients. RESULTS: The results of this series suggest that angiomatous proliferation within the retina is the first manifestation of the vasogenic process in this form of neovascular ARMD. Dilated retinal vessels and pre-, intra-, and subretinal hemorrhages and exudate evolve, surrounding the angiomatous proliferation as the process extends into the deep retina and subretinal space. One or more dilated compensatory retinal vessels perfuse and drain the neovascularization, sometimes forming a retinal­retinal anastomosis. Fluorescein angiography in these patients usually revealed indistinct staining simulating occult CNV. Indocyanine green angiography was useful to make an accurate diagnosis in most cases. It revealed a focal area of intense hyperfluorescence corresponding to the neovascularization ("hot spot") and other characteristic findings. Based on understanding of the nature and progression of the neovascularized process, patients with RAP were classified into three vasogenic stages. Stage I involved proliferation of intraretinal capillaries originating from the deep retinal complex (intraretinal neovascularization [IRN]). Stage II was determined by growth of the retinal vessels into the subretinal space (subretinal neovascularization [SRN]). Stage III occurred when CNV could clearly be determined clinically or angiographically. A vascularized pigment epithelial detachment and RCA were inconsistent features of this stage. CONCLUSIONS: Retinal angiomatous proliferation appears to be a distinct subgroup of neovascular ARMD. It may present in one of three vasogenic stages: IRN, SRN, or CNV. Whereas ICG angiography is helpful in diagnosing RAP and in documenting the stage of the neovascularized process, it is frequently difficult to determine the precise nature and location of the new vessel formation. It is important for clinicians to recognize the vasogenic potential and the associated manifestations of this peculiar form of neovascular ARMD so that a proper diagnosis can be made, and when possible, an appropriate management administered.

Treatment of polypoidal choroidal vasculopathy with photodynamic therapy. 2002.

PURPOSE: To study the effects of photodynamic therapy using verteporfin in the treatment of patients with subfoveal polypoidal choroidal vasculopathy (PCV). METHODS: A retrospective chart review of 16 consecutive patients with subfoveal PCV treated with photodynamic therapy using verteporfin was performed. RESULTS: The mean age of the patients involved was 70.5 years. The mean follow-up time was 12 months. The visual acuity improved in 9 (56.3 %), remained the same in 5 (31.3 %), and decreased in 2 (12.5 %). The mean change in visual acuity was an improvement of 2.38 lines, a difference that was highly significant (P = 0.004). The change in visual acuity was negatively correlated with increasing age. The final visual acuity was positively correlated with initial acuity and negatively correlated with age. These results were confirmed by multiple linear regression. No patient had any lasting complication from the treatment. CONCLUSIONS: Subfoveal PCV has no proven method of treatment. Although the follow-up time and the number of patients in this pilot study were limited, the encouraging results and lack of complications suggest that further study is indicated.

Unilateral acute idiopathic maculopathy. 1991.

This is a report of nine patients who experienced sudden, severe, unilateral central vision loss following a flulike illness. Each patient had an exudative detachment of the macula. All patients experienced a spontaneous resolution of the acute macular manifestations with near-complete recovery of vision. A characteristic "bull's-eye" appearance in the macula persisted. The acute manifestations of the disorder did not recur in any of the patients during the period of follow-up. The constellation of findings was suggestive of an inflammatory disease of the retinal pigment epithelium, but a specific causative agent could not be identified. The acute clinical and angiographic features, the natural course, and the residual pigment epithelial derangement were not consistent with any previously described disorder.

Sustained increased intraocular pressure related to intravitreal antivascular endothelial growth factor therapy for neovascular age-related macular degeneration.

PURPOSE: To describe a series of previously normotensive eyes experiencing sustained elevated intraocular pressure (IOP) associated with long-term intravitreal antivascular endothelial growth factor (VEGF) therapy for neovascular age-related macular degeneration (AMD). PATIENTS AND METHODS: Clinical data were reviewed for 25 eyes of 23 patients with neovascular AMD who had increased IOP while receiving interval doses of intravitreal ranibizumab and/or bevacizumab. All eyes had tolerated multiple anti-VEGF injections in the past without IOP elevations. RESULTS: After a mean of 20.0 anti-VEGF injections (range, 8-40 injections), the mean IOP was 29.8 mm Hg (range, 22-58 mm Hg), compared with a baseline of 16.9 mm Hg (range, 14-21 mm Hg). The mean highest IOP while receiving intravitreal anti-VEGF therapy was 35.8 mm Hg (range, 23-58 mm Hg). Overall, 23 of 25 cases required IOP management. In the remaining 2 cases, anti-VEGF dosing was switched from regular interval dosing to an optical coherence tomography-guided variable regimen, with subsequent improvement in IOP without antiglaucoma treatment. CONCLUSIONS: Serial injections of anti-VEGF agents may lead to persistent IOP elevations that require glaucoma therapy. The clinician should recognize this phenomenon, as it can occur even if the patient has tolerated multiple prior injections without IOP elevation. Further exploration of the relationship between anti-VEGF therapy and IOP is needed.

Focal retinal phlebitis.

PURPOSE: To report three cases of solitary, focal retinal phlebitis. METHODS: An observational case series. RESULTS: Three eyes in three patients were noted to have unilateral decreased vision, macular edema, and a focal retinal phlebitis, which was not at an arteriovenous crossing. All three patients developed a branch retinal vein occlusion at the site of inflammation. These patients had no other evidence of intraocular inflammation, including vitritis, retinitis, retinal vasculitis, or choroiditis, nor was there any systemic disorder associated with inflammation, infection, or coagulation identified. CONCLUSION: Focal retinal phlebitis appears to be an uncommon and unique entity that produces macular edema and ultimately branch retinal vein occlusion. In our patients, the focal phlebitis and venous occlusion did not occur at an arteriovenous crossing, which is the typical site for branch retinal venous occlusive disease. This suggests that our cases represent a distinct clinical entity, which starts with a focal abnormality in the wall of a retinal venule, resulting in surrounding exudation and, ultimately, ends with branch retinal vein occlusion.