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Retinal visual prostheses ("bionic eyes") have the potential to restore vision to blind or profoundly vision-impaired patients. The medical bionic technology used to design, manufacture and implant such prostheses is still in its relative infancy, with various technologies and surgical approaches being evaluated. We hypothesised that a suprachoroidal implant location (between the sclera and choroid of the eye) would provide significant surgical and safety benefits for patients, allowing them to maintain preoperative residual vision as well as gaining prosthetic vision input from the device. This report details the first-in-human Phase 1 trial to investigate the use of retinal implants in the suprachoroidal space in three human subjects with end-stage retinitis pigmentosa. The success of the suprachoroidal surgical approach and its associated safety benefits, coupled with twelve-month post-operative efficacy data, holds promise for the field of vision restoration.Clinicaltrials.gov NCT01603576.

Background: Our research goal is to develop a safe, reproducible surgical approach for implantation of a wide-field retinal stimulating array. The aim of this study was to evaluate the pathological response to acute implantation of a functional prototype electrode array in the suprachoroidal space. Methods: The surgical techniques to implant a 72 platinum electrode array fabricated on 8 × 13 × 0.4 mm polyimide and silicone substrate were developed in a pilot study in anesthetized cats. For the main study, nine eyes were implanted in vivo and unoperated eyes were used as controls. Surgery consisted of a temporal approach with a full-thickness scleral incision 5 mm posterior to the limbus. A suprachoroidal 'pocket' was created, the electrode array inserted to sit beneath the area centralis, and placement was confirmed visually. The eyes were collected subsequently for histopathology. Results: The array was consistently inserted into the suprachoroidal space beneath the area centralis in nine eyes. There was a significant hemorrhage in two cases where implantation was complicated by choroidal congestion. Retinal folding occurred only when the array tip was within 2.6 mm of the optic disc ( p < 0.01). There was choroidal incarceration at the incision in six eyes and scleral distortion at the array edges in five. No cases were found where the implant breached the retina, choroid, or sclera. Conclusions: A large stimulation array can be reliably inserted into the suprachoroidal space without trauma to the neuroretina. These findings suggest that this is an appropriate surgical approach for the placement of an electrode array for use in retinal stimulation. [ABSTRACT FROM AUTHOR]

Foveal microholes are a possible cause of unilateral or bilateral small central visual defects in the absence of other macular pathology. In 18 eyes of 17 patients we noted the following features: small, dark-reddish holes in the centre of the fovea ranging from 50 to 750 μm in size; normal adjacent retinal pigment epithelium and neuroepithelium; unilateral in most cases; males and females are equally affected; mean age 40 years; insidious onset; no history of direct eye trauma orsungazing; non-progressive; relatively favourable visual outcome; no relationship with regular macular holes; aetiology unknown. These distinctive features justify reporting these patients as an important separate group. [ABSTRACT FROM AUTHOR]

The high rise in pressure which sometimes follows laser trabeculoplasty is a serious and sight-threatening complication in patients with advanced glaucoma. In a previous study we found that patients undergoing laser trabeculoplasty were very unlikely to have a high rise in pressure if the initial pressure was less than 20 mmHg. In the present study a series of patients was given acetazolamide 500 mg immediately before laser trabeculoplasty if their pressures were greater than 20 mmHg. All patients were then monitored to see if this regime was effective in preventing a serious rise in intraocular pressure. Some of the patients with an initial pressure less than 20 mmHg still sustained a high rise in pressure after laser trabeculoplasty. A further series of patients was then given acetazolamide preoperatively and the postoperative rise in pressure was monitored two and 24 hours after trabeculoplasty. The acetazolamide prevented a high rise in pressure after laser trabeculoplasty in the majority of patients. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the advantages and disadvantages of the retention and removal of silicone oil in the treatment of complicated retinal detachments. Methods: The records of 344 patients (348 eyes) that underwent vitrectomy and silicone oil injection for complicated retinal detachments were abstracted and analysed. The anatomical and functional results, complications and influencing factors are discussed. The outcome in eyes after removal of the silicone oil was compared with the outcome in a comparable group of eyes in which the silicone oil was retained. Results: The overall retinal reattachment rate was 63% (220/348). The final vision of 5/300 or better was 52% (115/220) in those eyes with totally attached retinas. The silicone oil-related complications included keratopathy (23%) and secondary glaucoma (11%). Comparing removal of silicone oil with retention of silicone oil, we found: (i) there was no statistical difference in the redetachment rate (19 vs 17%); (ii) Oil-removed eyes had a better final vision ( P < 0.05); and (iii) keratopathy (13 vs 23%), secondary glaucoma (11 vs 25%) and optic nerve atrophy (4 vs 18%) were significantly lower in oil-removed eyes. Conclusion: Silicone oil injection is useful in the treatment of complicated retinal detachments. For reducing the incidence of complications, early removal of silicone oil is recommended in those cases in which the retina is attached, all breaks adequately closed and traction relieved. [ABSTRACT FROM AUTHOR]

Background:The AIDS database at Fairfield Hospital, Melbourne, maintains information on eye pathology as identified by the three visiting ophthalmologists. Patients underwent an eye consultation: if they had ocular symptoms; if signs were seen on direct ophthalmoscopy by physicians; or when their CD4+ve cell count fell below 50/μL. The first AIDS-associated eye signs were identified in mid-1984. In the subsequent decade, 3257 patients in Victoria tested positive for HIV, and 845 of the 1123 who developed AIDS were treated at Fairfield Hospital. Methods:We undertook a retrospective review of the Fairfield Hospital database to identify the AIDS-associated ocular problems seen. Results:Some 723 patients had an eye consultation. In the earliest stage of HIV infection, minor non-specific ophthalmic involvement may occur. As the disease progresses, microvasculopathy (cottonwool spots and haemorrhages) appears. External disease also occurs such as molluscum contagiosum and Kaposi's sarcoma of the conjunctiva. With more suppression of the immune system, opportunistic infections become common, and have a considerable visual morbidity. Cerebral toxoplasmosis (117 patients) is only rarely associated with ocular involvement (three patients), but cytomegalovirus (CMV) commonly causes retinitis [204 patients (24%)]. It has been the AIDS-defining illness in 26 patients. A majority had the disease confined to one eye. Mean CD4 cell count at onset is 15±5 μL and it has been associated with a viraemia in all but two patients. Late complications of CMV retinitis include relapse in 41 (20%), spread to the other eye in 24 (12%), and retinal detachment in 30 (15%). Visual impairment follows from retinal destruction, optic nerve involvement, and retinal detachment. Conclusion:The ophthalmic workload from late ocular complications of AIDS is increasing. Newer and more effective methods of treatment are being developed. Ophthalmologists are becoming more aware of the need for universal precautions to avoid risks from this and other blood-borne infections. [ABSTRACT FROM AUTHOR]

The ophthalmic features are reported of a member of an Australian pedigree with three affected individuals spanning two generations with a hereditary endotheliopathy syndrome resulting in retinopathy, leukoencephalopathy and nephropathy. The index case initially presented with asymptomatic retinopathy, cerebral microvascular disease, nephropathy and raised inflammatory markers. The clinical, neuro-radiological, biochemical and histopathological findings in this patient are consistent with a diagnosis of hereditary endotheliopathy, retinopathy, nephropathy and stroke (HERNS). Linkage analysis has identified a locus for HERNS on chromosome 3p21.1-p21.3. This locus is shared with two other diseases: hereditary vascular retinopathy (HVR) and cerebroretinal vasculopathy (CRV). Although peripheral retinal involvement is a feature of HVR, it has not previously been described in HERNS. This case represents a novel phenotype of HERNS, and serves to blur the distinction between the vasculopathies mapping to chromosome 3p21. Although previously thought to be distinct clinical entities, it is possible that HERNS, HVR and CRV simply represent different phenotypes of the same disease. This will only be clarified with the identification of the gene or genes. This case also raises the question of how best to manage rare forms of vascular retinopathy. [ABSTRACT FROM AUTHOR]