Faculty Bibliography

Purpose Poly(dimethylsiloxane) polymers (commonly known as silicone oil) have been frequently used in retinal surgery as a tamponade. Emulsification of these oils has been a difficult and persistent problem. Persistence of the oil following vitrectomy with fluid exchange has been confirmed by contact B-scan ultrasonography. In addition, infiltration of the silicone oil into the retina and optic nerve has been demonstrated by SD-OCT and adaptive optics imaging. This study intends to directly visualize the emulsions formed by silicone oil used in retinal surgery by multimodal imaging. Methods Silicone oil that was removed from eyes by fluid exchange and vitrectomy having been used as a surgical tamponade was subjected to chemical and electron micrographic analysis. 0.1 mL of silicone oil was washed with 2 mL of sterile irrigating solution (BSS, Alcon, TX). The mixture was then vortexed for 60 s and allowed to sit at 25 degreeC for 24 hours. The supernatant was decanted and placed on carbon-coated copper grids for transmission electron microscopy (TEM) and cryo-TEM analysis. Results BSS was suficient to emulsify the removed silicone oil. Transmission electron microscopy revealed nano-size (<100 nm) and micron-sized (<1 mum) oil-in-water emulsions. These emulsions are several orders of magnitude smaller than previously reported. These droplet sizes are similar to the size of silicone oil droplets that have been found in the tissues of the retina and optic nerve using optical coherence tomography and adaptive optics imaging. Conclusions This demonstrates that silicone-soluble components of the eye partition into the silicone oil after its instillation as a surgical tamponade. These silicone-soluble components are alone suficient to cause emulsification. The equilibration of the silicone oil with lipid-soluble components in the eye is consistent with phase-equilibrium behavior. Further analysis of the silicone oil to determine the identity of the emulsifying agents is ongoing

The authors report the in vivo visualization through multimodal imaging of silicone oil in the vitreous cavity, optic nerve, and retina of a patient 11 years after surgical removal of the main tamponade. Contact B-scan ultrasonography revealed countless small echogenic particles in the vitreous cavity and a hyperreflective structure within the optic nerve head. Swept-source optical coherence tomography showed multiple round hyporeflective spaces within the substance of the prelaminar optic nerve head. Adaptive optics imaging revealed numerous particles in the optic nerve head and within the retina in the same plane as the photoreceptors, with similar size and shape to the silicone oil droplets in the vitreous cavity. The authors hypothesize that in this case, the silicone oil droplets in the retina and optic nerve head may be associated with the patient's otherwise unexplained progressive visual loss.

Twenty-five patients with central serous pigment epitheliopathy (CSP), also known as central serous chorioretinopathy, have been observed to have inferior hemispheric retinal pigment epithelial atrophic tracts, presumptive of antecedent retinal detachments. Five of these patients were noted to have clinically discernible, dependent peripheral retinal detachments. The clinical and fluorescein angiographic features of these patients are reviewed. Alterations in the retina, the retinal pigment epithelium (RPE) and the choroid are also described. They include the commonly associated manifestations of CSP such as RPE leaks and macular detachment as well as some newly recognized disturbances such as retinal capillary dilatation (telangiectasia), retinal capillary leakage, retinal lipid deposition, cystoid macular edema, choriocapillaris atrophy, choroidal neovascularization and disciform scarring.

A series of young adult patients developed solar retinopathy during sun exposure over a two-day period in a particular region of the United States during March of 1986. Evaluation of the photobiological and geophysical parameters involved in solar retinitis are presented. A multifactorial pathogenesis is proposed. Of interest, a possible increase in terrestrial ultra-violet B radiation secondary to a localized relatively low ozone column during the days involved may have contributed to the retinal damage. Recommendations for protection from solar retinitis are noted.

PURPOSE: To describe a patient with birdshot retinochoroidopathy (BRC) with bilateral choroidal neovascularization (CNV) who was treated with intravitreal injection of bevacizumab and antiinflammatory medications. METHOD: Interventional case report. PATIENT: A 35-year-old woman with bilateral CNV associated with BRC. RESULTS: The patient was treated with intravitreal injection of triamcinolone, photodynamic therapy, and intravitreal injection of bevacizumab in one eye, while the fellow eye was treated with intravitreal injection of triamcinolone. Immunosuppressive therapy was performed in the course of the treatment. Not only did the neovascularization respond, but the birdshot lesions vanished as well. DISCUSSION: BRC can have secondary CNV that, as in the current case, responds favorably to treatment. We serendipitously observed regression of the choroidal inflammatory lesions with intravitreal injection of triamcinolone.

PURPOSE: To delineate the 3-dimensional (3-D) relationship in vitreomacular traction (VMT) and idiopathic epiretinal membrane (ERM). DESIGN: Observational case series. METHODS: Forty-eight evaluable eyes of 35 patients with VMT or idiopathic ERM were investigated with spectral-domain (SD) optical coherence tomography (OCT). VMT was defined as focal if the diameter of the vitreous attachment was 1500 microm or less and broad if it was more than 1500 microm. The 3-D OCT representation of vitreomacular interface abnormalities was evaluated. RESULTS: Focal VMT was seen in five eyes. Broad VMT was seen in seven eyes. Of these 12 eyes, concurrent ERMs under the detached vitreous were seen in 10 eyes and zones of hyperreflectivity affecting the adjacent detached posterior hyaloid face were seen in 11 eyes. Eyes with focal VMT showed a foveal cavitation, whereas eyes with broad VMT had more widespread cystoid macular edema. Idiopathic ERM was seen in 36 eyes; 30 had complete posterior vitreous detachment (PVD), five had partial PVD associated with attached posterior hyaloid at some peripheral portion of the ERM, and one had no PVD. CONCLUSIONS: The SD OCT with 3-D image reconstruction provided unprecedented visualization of VMT and idiopathic ERM. The vitreous attachment to the macula can be subclassified into two subgroups, each having specific induced alterations in retinal anatomy. Most of the eyes with VMT had concurrent ERM, whereas several eyes with idiopathic ERM had attachment of the vitreous to some portion of the ERM, which suggests there is significant overlap between VMT and idiopathic ERM

BACKGROUND: Spontaneous scleral rupture in association with retinochoroidal coloboma is a rare and poorly understood event, with few reports in the literature. METHODS: Interventional case report. RESULTS: A 40-year-old man had a spontaneous decline in visual acuity with hypotony in the right eye. Photographic, fluorescein angiographic, optical coherence tomographic, ultrasonographic, and computed tomographic findings demonstrated that the cause was spontaneous rupture of ectatic sclera adjacent to a retinochoroidal coloboma. Surgical repair with primary suture imbrication and support with a segmental scleral buckle restored the intraocular pressure and baseline visual acuity. CONCLUSIONS: The adjacent but distinct locations of the retinochoroidal coloboma and ectatic sclera in this case suggest that during embryogenesis a full thickness defect was present in the eye wall, but due to differential growth rates, the scleral and retinochoroidal defects ceased to be superimposed. Persistent hypotony implies continued flow of liquefied vitreous or aqueous through the defect. Suture imbrication and scleral buckling can be a successful treatment option.