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Concept: Retinal detachment

147

Although retinal neurodegenerative conditions such as age-related macular degeneration, glaucoma, diabetic retinopathy, retinitis pigmentosa, and retinal detachment have different etiologies and pathological characteristics, they also have many responses in common at the cellular level, including neural and glial remodeling. Structural changes in Müller cells, the large radial glia of the retina in retinal disease and injury have been well described, that of the retinal astrocytes remains less so. Using modern imaging technology to describe the structural remodeling of retinal astrocytes after retinal detachment is the focus of this paper. We present both a review of critical literature as well as novel work focusing on the responses of astrocytes following rhegmatogenous and serous retinal detachment. The mouse presents a convenient model system in which to study astrocyte reactivity since the Mϋller cell response is muted in comparison to other species thereby allowing better visualization of the astrocytes. We also show data from rat, cat, squirrel, and human retina demonstrating similarities and differences across species. Our data from immunolabeling and dye-filling experiments demonstrate previously undescribed morphological characteristics of normal astrocytes and changes induced by detachment. Astrocytes not only upregulate GFAP, but structurally remodel, becoming increasingly irregular in appearance, and often penetrating deep into neural retina. Understanding these responses, their consequences, and what drives them may prove to be an important component in improving visual outcome in a variety of therapeutic situations. Our data further supports the concept that astrocytes are important players in the retina’s overall response to injury and disease.

Concepts: Neuron, Retina, Retinitis pigmentosa, Diabetic retinopathy, Retinal detachment, Glial cells, Macular degeneration, Radial glia

99

Adipose tissue-derived “stem cells” have been increasingly used by “stem-cell clinics” in the United States and elsewhere to treat a variety of disorders. We evaluated three patients in whom severe bilateral visual loss developed after they received intravitreal injections of autologous adipose tissue-derived “stem cells” at one such clinic in the United States. In these three patients, the last documented visual acuity on the Snellen eye chart before the injection ranged from 20/30 to 20/200. The patients' severe visual loss after the injection was associated with ocular hypertension, hemorrhagic retinopathy, vitreous hemorrhage, combined traction and rhegmatogenous retinal detachment, or lens dislocation. After 1 year, the patients' visual acuity ranged from 20/200 to no light perception.

Concepts: Retina, Eye, Visual perception, Visual acuity, Ophthalmology, Retinal detachment, Snellen chart, Vision loss

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PurposeTo evaluate the effects of intravitreal autologous plasmin enzyme (APE) in patients with focal vitreomacular traction (VMT).MethodsAPE was obtained by incubation of patient-derived purified plasminogen with streptokinase, and intravitreally injected 5-12 days later. Twenty-four hours after injection, in case of incomplete VMT release, a pars plana vitrectomy was performed. The hyaloid internal limiting membrane adherence and removal of the posterior hyaloid were intraoperatively evaluated.ResultsThirteen patients were recruited. During preparation of APE, five patients had spontaneous release of VMT. Eight patients received APE injection (2 IU). In five patients, spontaneous resolution of VMT occurred before APE administration. Twenty-four hours after injection, persistence of VMT was detected in all the eight treated patients. Best-corrected visual acuity was 0.51±0.37 LogMAR at baseline, improving to 0.23±0.14 LogMAR at 6 months (P=0.002). Foveal thickness was 464±180 μm at baseline, reducing to 246±59 μm at 6 months (P<0.001). Hyaloid was intraoperatively judged 'partially detached' in seven cases and 'totally detached' in one case. Hyaloid peeling was evaluated 'easy' in six eyes and 'very easy' in two eyes.ConclusionsIn the current study, there was a large percentage of spontaneous resolution of VMT before an APE administration. A single intravitreal APE injection seems insufficient to induce a complete posterior vitreous detachment in these patients.Eye advance online publication, 14 December 2012; doi:10.1038/eye.2012.248.

Concepts: Eye, Visual acuity, Ophthalmology, Vitrectomy, Retinal detachment, Vitreous humour, Epiretinal membrane, Posterior vitreous detachment

28

Surgery for rhegmatogenous retinal detachment (RRD) should usually be performed as soon as possible. However, a risk of operating in an emergency setting has to be considered against the risk of delaying it.

Concepts: Retina, Retinal detachment

28

PURPOSE: To report an association of congenital optic nerve anomalies with peripheral retina nonperfusion and to describe the clinical manifestations and treatment. DESIGN: Retrospective, observational case series. PARTICIPANTS: Fifteen patients with congenital optic nerve anomalies referred for pediatric retina consultation were studied. Sixteen eyes of 9 patients with optic nerve hypoplasia and 8 eyes of 6 patients with other congenital optic nerve anomalies, including optic nerve coloboma, morning glory disc, and peripapillary staphyloma, were included. METHODS: All patients underwent examinations under anesthesia. Wide-angle retina photographs and fluorescein angiograms were reviewed. The severity of nonperfusion was graded. The presence of fibrovascular proliferation (FP), vitreous hemorrhage (VH), and tractional retinal detachment (TRD) were documented. Anatomic outcome after treatment was recorded. MAIN OUTCOME MEASURES: Severity of nonperfusion, occurrence of secondary complications, and the anatomic outcome of patients who underwent laser treatment. RESULTS: In patients with optic nerve hypoplasia, 12 of 16 eyes (75%) had severe peripheral nonperfusion, 12 of 16 eyes (75%) had FP, 3 of 16 eyes (19%) had VH, and 10 of 16 eyes (63%) had TRD. Six of these eyes with severe nonperfusion received laser photocoagulation to the nonperfused retina; laser-treated retinas remained attached in all 6 eyes. In patients with the other optic nerve anomalies, 7 of 8 eyes (88%) had mild to moderate nonperfusion, 2 of 8 eyes (25%) had FP, 1 of 8 eyes (12%) had VH, and 2 of 8 eyes (25%) had TRD. Six of 9 patients (67%) with optic nerve hypoplasia and 1 of 6 patients (17%) with other anomalies had a coexisting congenital brain disease. CONCLUSIONS: Congenital optic nerve anomalies may be associated with peripheral retina nonperfusion and the secondary complications of FP, VH, and TRD. In this select group of patients, the nonperfusion associated with optic nerve hypoplasia seemed to be more severe and associated more frequently with secondary complications. Peripheral retina examination in eyes with optic nerve anomalies may identify nonperfusion or FP. Laser treatment of the avascular retina may have helped prevent complications from proliferative retinopathy in eyes clinically observed to have progressed or considered at risk for progression to proliferative retinopathy. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Concepts: Brain, Retina, Eye, Ophthalmology, Diabetic retinopathy, Retinal detachment, Optic nerve, Optic nerve hypoplasia

28

Purpose. To report the efficacy and ocular tolerance of a new tamponade made with ether and silicone oil (HeavySil [HSIL]) for the treatment of retinal detachment (RD) complicated by inferior proliferative vitreous retinopathy (PVR).
Methods. Prospective noncomparative interventional study on 31 consecutive eyes that underwent pars plana vitrectomy and were treated with HSIL as an intraocular tamponade. All patients presented with at least one retinal break and grade B-C PVR located between 4 and 8 o'clock. The main endpoint criteria were retinal reattachment after the removal of HSIL and complications arisen from the use of this tamponade.
Results. Primary anatomic success was achieved in 27 out of 31 cases. Mean visual acuity improved from logMAR 1.4 (SD 0.7) to logMAR 1.1 (SD 0.6) (p=0.02).
The main complications reported were cataract formation (5 out of 7 phakic eyes cases), clinically visible emulsification (6 cases), and difficulty of oil removal in 3 cases. Severe intraocular inflammation with HSIL in situ was found in only one case.
Conclusions. HeavySil, a saturated solution of ether with silicone oil, is a safe and effective tamponade agent for the treatment of complicated RD. The most common complications are cataract formation and oil emulsification.

Concepts: Retina, Visual acuity, Ophthalmology, Vitrectomy, Diabetic retinopathy, Retinal detachment, Intraocular lens, Vision loss

27

Conventional treatment of idiopathic central serous chorioretinopathy (ICSC) consists of argon laser, photodynamic therapy, or observation. However, in cases of atypical bullous ICSC with exudative detachment preventing any laser therapy, a surgical approach with external drainage of fluid has been performed. We present a case of ICSC with persistent macula involving exudative retinal detachment without evidence of uveitis that responded favorably to internal drainage by vitrectomy along with a scleral buckle placement. Our case, treated with internal drainage, also demonstrated successful long-term reattachment of the serous retinal detachment without any additional complications from the surgery.

Concepts: Medicine, Laser, Retina, Ophthalmology, Retinal detachment, Central serous retinopathy, Posterior vitreous detachment, Scleral buckle

26

It is widely accepted that the origin of subretinal fluid in rhegmatogenous retinal detachment (RRD) is liquid vitreous and that posterior vitreous detachment (PVD) and associated retinal tears are caused by vitreoretinal traction from intra-ocular currents, contraction of collagen fibers, and gravity. These explanations, however, are incomplete. We present a new synthesis of experimental and clinical evidence, updating understanding of fundamental pathophysiological processes in RRD. Misdirected aqueous flow is shown to more convincingly explain the origin of subretinal fluid in clinical RRD, to be the most likely cause of acute PVD and retinal tear formation, and also to contribute to initial detachment of the retina at retinal tears. Misdirected aqueous flow in RRD is a pathophysiological process, rather than the “aqueous misdirection syndrome”, and occurs without visible anterior chamber shallowing or acute glaucoma.

Concepts: Retina, Glaucoma, Ophthalmology, Retinal detachment, Myopia, Vitreous humour, Posterior vitreous detachment, Lattice degeneration

26

To compare using pars plana vitrectomy (PPV) combined with a scleral buckle versus primary vitrectomy alone in patients with rhegmatogenous retinal detachment at high risk for postoperative proliferative vitreoretinopathy (PVR).

Concepts: Retina, Ophthalmology, Vitrectomy, Retinal detachment, Scleral buckle

26

Abstract Background: Intraocular inflammation of the posterior segment may be associated with neoplastic, infectious, and inflammatory diseases. Biopsy of vitreous and additional ocular tissue might be required for a definitive diagnosis. We therefore aimed to investigate the safety and usefulness of diagnostic vitrectomy in intraocular inflammation. Method: We performed an observational retrospective study of patients who underwent vitreous biopsy due to atypical intraocular inflammation, experienced failed resolution to empirical therapy, or for whom there was suspicion of an underlying neoplastic process. Results: Seventy consecutive patients were included due to idiopathic uveitis of the posterior segment unresponsive to systemic corticosteroids (n = 33, 47%), suspected vitreoretinal or choroidal lymphoma (n = 18, 26%), viral retinitis (n = 17, 24%), and suspected endogenous endophthalmitis (n = 2, 3%). Suspected viral retinitis was most often confirmed (13/17, 76%), followed by lymphoma (6/18, 33%). Remarkably, a proportion of suspected idiopathic uveitis was infectious (7/33, 21%). The most prevalent adverse event following diagnostic vitrectomy was cataract surgery in phakic patients (n = 16/41, 39% of phakic patients). Retinal detachments were observed chiefly in infectious or neoplastic disease (n = 5, 7%) after a median time of 105 days. Conclusion: Diagnostic vitrectomy was helpful in substantiating the clinical suspected diagnosis of posterior segment inflammation. Potential secondary adverse events should be kept in mind.

Concepts: Inflammation, Scientific method, Cancer, Asthma, Neoplasm, Retina, Ophthalmology, Retinal detachment