Orbital Venous Varices: A Rare Bilateral Asymptomatic Presentation.

This report illustrates a case of asymptomatic bilateral orbital varices in a 64-year-old Caucasian male. The orbital varices were incidentally discovered while investigating the patient's initial presentation of bilateral chorioretinal scars and optic nerve head drusen. Magnetic resonance imaging (MRI) of the brain and orbits with contrast confirmed the presence of bilateral varices of the inferior ophthalmic veins and pterygoid plexuses. The occurrence of bilateral orbital varices is quite rare, and few asymptomatic cases have been described in the literature.

Intravitreal Injection-Induced Migraine Headaches.

A case of migraine headache triggered by intravitreal injection, and aborted by retrobulbar injection, is reported. To date, migraine and related cephalgia have not been reported after intravitreal injection. Ophthalmologists and neurologists should be aware of this potential sequela of a very common procedure.

HLA associations in chronic vision threatening uveitis.

Chronic uveitides can lead to serious sequlae over time including blindness. Human Leukocyte antigen (HLA) plays an important role in immunological response of the eyes. Some of these uveitides are associated with certain Human Leukocyte antigen (HLA) types. This article reviews these relationships and their significance.

Decompression Retinopathy after ExPRESS Shunt Implantation for Steroid-Induced Ocular Hypertension: A Case Report.

Purpose. To present a unique case of decompression retinopathy after the implantation of ExPRESS drainage device. Method. A 25-year-old female patient underwent implantation of ExPRESS drainage device in the left eye for the management of steroid-induced ocular hypertension. Results. On the postoperative day one, best-corrected visual acuity in the left eye was 20/50. Fundus examination revealed diffuse intraretinal hemorrhages, some white-centered, throughout the retina. There was also marked tortuosity to the retinal vasculature and no evidence of choroidal effusion. Intravenous fluorescein angiography and indocyanine green did not contribute to the aetiopathogenesis. Conclusion. Decompression retinopathy can occur following the implantation of ExPRESS drainage device. It is very important to be aware of this complication in patients with relatively high intraocular pressure who is planned for filtration surgery, including the ExPRESS implant.

Cutting the encircling band.

PURPOSE: To report the effect of cutting the encircling band on ocular blood flow. METHODS: In an interventional case series of 27 eyes with an encircling band, the ocular pulse amplitude (OPA) was measured and pulsatile ocular blood flow (POBF) derived and compared with fellow eyes. The bands were cut in 11 eyes and the POBF measured at 1 month, 3 months, and 1 year. Changes in POBF, buckle height, and visual acuity were determined. RESULTS: The presence of the encircling band reduced the POBF to a mean of 43% (P < 0.001) of the fellow eye. Cutting the band resulted in a mean recovery to 85.6%. No retina detached after cutting, buckle height was only slightly diminished, and the visual acuity was unaffected. CONCLUSION: An encircling band diminishes the POBF. Cutting the band restores significant flow.

Expansion of visual receptive fields in experimental glaucoma.

Glaucoma is a major cause of blindness and is characterized by death of retinal ganglion cells. In a rat model of glaucoma in which intraocular pressure is raised by cautery of episcleral veins, the somata and dendritic arbors of surviving retinal ganglion cells expand. To assess physiological consequences of this change, we have measured visual receptive-field size in a primary retinal target, the superior colliculus. Using multiunit recording, receptive-field sizes were measured for glaucomatous eyes and compared to both those measured for contralateral control eyes and to homolateral eyes of unoperated animals. Episcleral vein occlusion increased intraocular pressure. This was accompanied by a significant increase in receptive-field size across the superior colliculus. The expansion of receptive fields was proportional to both degree and duration of the increase of intraocular pressure. We suggest that this increase in the size of receptive fields of glaucomatous eyes may be related to the increase in the size of dendritic arbors of the surviving ganglion cells in retina.

Spontaneous resolution of unilateral vitreomacular traction.

Vitreomacular traction (VMT) caused visual symptoms in two healthy young adults but spontaneously resolved within four weeks without any sequelae. Optical coherence tomography (OCT) and fundus photographs proved vital in documenting the rare complete resolution of VMT. It is prudent to monitor for spontaneous resolution of VMT in young healthy adults.

Dorzolamide and timolol saves retinal ganglion cells in glaucomatous adult rats.

PURPOSE: This study was designed to evaluate the effects of a dorzolamide-timolol combination or dorzolamide on retinal ganglion cell (RGC) density and intraocular pressure (IOP) in glaucomatous eyes of adult rats. METHODS: Glaucoma was induced in the right eye of adult Wistar rats by episcleral venous occlusion. One experimental group was administered dorzolamide 2%-timolol 0.5% combination eye drops, while the other experimental group was administered dorzolamide 2% eye drops. Control groups had surgery without drug administration. Drug application was initiated either 2 weeks before surgery (Group A), from the day of surgery (Group B), 2 weeks after surgery (Group C), or 4 weeks after surgery (Group D). RGCs were labeled by intratectal Fluorogold injections and counted from flat-mount preparations, and IOP was measured using Tonopen. RESULTS: Both dorzolamide-timolol combination and dorzolamide, when applied topically, significantly reduced IOP and improved RGC densities in experimental eyes when compared to control eyes. Earlier initiation, as well as longer duration of drug application, resulted in higher RGC densities. CONCLUSIONS: Topical application of a dorzolamide-timolol combination or dorzolamide saved RGCs to a significant extent and reduced IOP in glaucomatous rat eyes.

Ciliary neurotrophic factor and its receptors are differentially expressed in the optic nerve transected adult rat retina.

Ciliary neurotrophic factor (CNTF) has been implicated in the survival and regeneration of adult rat retinal ganglion cells (RGCs). Expression of CNTF and its receptors, ciliary neurotrophic factor receptor alpha (CNTFRalpha) and leukemia inhibitory factor receptor (LIFR) was studied in normal, 6-h, 1-, and 3-day optic nerve transected retinas. Optic nerve transection was performed on the right eye in one group. In the other group, it was performed 5 days after intratectal Fluorogold injection. Retinas were studied using immunohistochemical labeling and Western blot analysis. Astrocytes were labeled with GFAP and Müller cells with glutamine synthetase. CNTF was observed in identifiable astrocytes and Müller cells, and its intensity increased in the experimental retinas. CNTFRalpha was localized on RGCs in experimental retinas. LIFR was localized on RGCs and Müller cells in normal and experimental retinas. CNTF and its receptors are differentially expressed after optic nerve transection and could help delay RGC death in such a stressful environment.