BRANCH RETINAL VEIN OCCLUSION SECONDARY TO A RETINAL ARTERIOLAR MACROANEURYSM: A NOVEL MECHANISM SUPPORTED BY MULTIMODAL IMAGING.

BACKGROUND/PURPOSE: To report a case of a branch retinal vein occlusion secondary to a retinal arteriolar macroaneurysm (RAM). METHODS: Retrospective case report describing examination findings, treatment outcome and unique multimodal imaging features demonstrated on fluorescein angiography, optical coherence tomography, optical coherence tomography angiography and adaptive optics photography of the retinal vessels and RAM. RESULTS: A 61-year-old man presented with 20/200 vision in the right eye because of a branch retinal vein occlusion secondary to a RAM. After sector panretinal photocoagulation and a course of 24 intravitreal antivascular endothelial growth factor injections over 4 years, visual acuity improved to 20/25. Fluorescein angiography showed filling of the RAM even after 4 years. Optical coherence tomography angiography demonstrated venous collateral vessels in both the superficial and deep capillary plexuses, and adaptive optics imaging revealed a gap between the RAM wall and occluded vein. CONCLUSION: Multimodal imaging of this unusual presentation illustrated a novel mechanism of branch retinal vein occlusion in which a primary RAM adjacent to the junction of two retinal veins led to obstruction of venous flow without evidence of direct compression. This supports the theory that perianeurysmal microenvironment changes may be of importance in the pathogenesis of venous occlusion.

Effect of triamcinolone acetonide on vascular endothelial growth factor and occludin levels in branch retinal vein occlusion.

PURPOSE: To investigate the molecular mechanism by which triamcinolone acetonide (TA) may reduce edema in a porcine model of branch retinal vein occlusion (BRVO). DESIGN: Animal study. METHOD: After baseline ophthalmoscopic examination and fundus photography, a BRVO was created photothrombotically in each eye of 6 pigs, using argon green photocoagulation and intravenous Rose Bengal. Following this, the left eye was injected intravitreally with 4 mg/0.1 ml TA. After 11 weeks, the eyes were re-examined. Fluorescein angiography, in addition to ophthalmoscopy and fundus photography, was performed. Following sacrifice of the animals, the eyes were enucleated and processed. The distribution of vascular endothelial growth factor (VEGF), occludin, and glial fibrillary acidic protein (GFAP) were localized by immunofluorescence cytochemistry on 10 microm frozen retinal sections of TA-treated and untreated eyes. RESULTS: Retinal VEGF levels were significantly lower in the TA-treated eyes as compared with the untreated eye (P = .002). Conversely occludin levels were significantly higher in the treated eye (P = .026). There was also a significant reduction in GFAP immunoreactivity in the Muller cells of the treated eyes (P = .015) with no statistical significance in the astrocytes (P = .065). CONCLUSION: Intravitreal TA down regulates VEGF, which may prevent a decrease in occludin and also inhibits an increase in GFAP expression in Muller cells. These events may contribute to a reduction in the blood retinal barrier breakdown that occurs in BRVO and promote resolution of the associated retinal edema.

Intravitreal voriconazole for the treatment of endogenous endophthalmitis caused by Scedosporium apiospermum.

Scedosporium apiospermum is an increasingly recognized cause of endogenous fungal endophthalmitis in immunocompromised patients. The authors describe two patients with endogenous S. apiospermum endophthalmitis treated with intravitreal and systemic voriconazole. Despite a prolonged course of systemic antifungal treatment, both patients subsequently required enucleation for intractable ocular pain due to secondary scleritis. Histological examination of the globes demonstrated the presence of fungal hyphae. Endogenous S. apiospermum endophthalmitis need to be considered in the differential diagnosis of necrotizing retinitis. Despite its efficacy in suppressing disseminated S. apiospermum infection, voriconazole may be ineffective in the treatment of endogenous S. apiospermum endophthalmitis especially if treatment is delayed.

Corneal perforation due to severe peripheral ulcerative keratitis in Crohn disease.

PURPOSE: To describe corneal perforation secondary to severe peripheral ulcerative keratitis (PUK) in a patient with Crohn disease. METHODS: Interventional case report. RESULTS: A 72-year-old male with biopsy-proven Crohn disease presented with reduced vision, PUK, and corneal perforation in the right eye. Despite initial treatment with intravenous methylprednisolone and a conjunctival flap, a tectonic sectorial penetrating keratoplasty was required to preserve the globe and achieve a good visual result. CONCLUSIONS: Crohn disease may be associated with severe PUK leading to corneal perforation. Tectonic corneal grafting combined with treatment of the underlying systemic disease was associated with a favorable outcome.

Intravitreal triamcinolone for the treatment of ischemic macular edema associated with branch retinal vein occlusion.

PURPOSE: To evaluate the safety and efficacy of intravitreal triamcinolone acetonide (IVTA) for ischemic macular edema associated with branch retinal vein occlusion (BRVO) and foveal ischemia. DESIGN: Prospective interventional case series. METHODS: setting: Clinical practice. study population: Eighteen eyes of 18 patients with macular edema associated with BRVO and foveal ischemia. intervention: Four mg IVTA. main outcome measures: Visual acuity (VA), optical coherence tomography, macular thickness measurements, and treatment-related complications. RESULTS: The mean duration of BRVO before treatment was 14 months. All patients were followed for a minimum of nine months, and 12 patients completed 12 months follow-up. The mean logarithm of the minimum angle of resolution (logMAR) VA improved significantly from 0.81 +/- 0.36 at baseline to 0.65 +/- 0.30 at one month (P = .03) but did not vary significantly from baseline at three, six, nine, and 12 months. Macular thickness improved significantly in all eyes from a mean of 400 +/- 134 mum preinjection, to 228 +/- 58 mum at one month (P < .01) and 256 +/- 121 mum at three months (P < .01) but did not vary significantly from baseline at six, nine, and 12 months. Eight eyes developed posterior subcapsular cataract, intraocular pressure (IOP) exceeded 21 mm Hg in four eyes, and two eyes developed vitreomacular traction during follow-up. CONCLUSIONS: IVTA is effective in reducing ischemic macular edema associated with BRVO and foveal capillary nonperfusion. This reduction is often associated with a temporary improvement in VA. Raised IOP and development of posterior subcapsular cataract are disadvantages of this treatment.

Videoendoscope-guided fluorescein-assisted vitrectomy for phakic malignant glaucoma.

Malignant glaucoma is a rare secondary glaucoma classically occurring after intraocular surgery in eyes with primary angle closure. Pars plana vitrectomy is reserved for the treatment of malignant glaucoma when medical and laser treatment fail. The primary aim of surgery is the removal of the anterior vitreous to reduce resistance to aqueous flow into the anterior chamber. In phakic eyes, conventional pars plana vitrectomy without lens extraction is frequently unsuccessful because of difficulty visualizing the normally transparent anterior vitreous, combined with the technical challenge of removing the anterior vitreous without damaging the crystalline lens. We describe a technique of intraocular, videoendoscope-guided, fluorescein-assisted pars plana vitrectomy that enables direct visualization and thorough removal of the anterior vitreous without the need for lens extraction in prepresbyopic patients without cataract.

Optical coherence tomography under general anesthesia in a child with nystagmus.

PURPOSE: To describe a method that permits optical coherence tomography scanning to be performed under general anesthesia. DESIGN: Observational case report. METHODS: A 7-year-old child underwent optical coherence tomography scanning under general anesthesia. He was positioned prone, with the neck extended to enable vertical facial alignment on the scanner. An anti-Trendelenburg trend on the operating table minimized the degree of neck extension required. Intravenous fluids, modest ventilator airway pressures, and compression stockings were used to minimize perioperative hemodynamic disturbance and the potential for orthostatic hypotension associated with the anti-Trendelenburg trend. RESULTS: High-quality, diagnostically important optical coherence tomography scans were obtained. CONCLUSION: With appropriate patient positioning and anesthetic management, optical coherence tomography scanning can be performed on uncooperative adults and children under general anesthesia.