Background: In glaucoma the optic radiation may be affected by ascending degeneration and/or ageing, which may be associated with cerebral microangiopathy. This study classified groups of patients who are distinguishable related to their retinal nerve fiber layer thickness (RNFL) and axonal integrity/ demyelination of the optic radiation that were measured by diffusion tensor imaging (DTI). The additional effect of ageing and microangiopathy was investigated. Design: Retrospective comparative observational study. Participants: Fifty-six patients diagnosed with glaucoma of different entities (age 60.3±13.0 years) and 16 patients with normal optic nerve head (age 50.3±14.3 years) Methods: Multimodal MRI including DTI of the optic radiation and measurement of the RNFL thickness by Spectralis Optical Coherence Tomography. Two step cluster analysis involved the DTI parameters, RNFL thickness, age, and stage of cerebral microangiopathy. Main Outcome Measures: Mean, axial, and radial diffusivity (low values denote normal neuronal tracts). Results: Three clusters were found. Features of cluster 1 (n=17) were middle age, low DTI-diffusivity and high RNFL. Cluster 2 (n=18) was middle-aged, had low DTI-diffusivity and low RNFL. The third cluster (n=37) was of older age, had high DTI-diffusivity and low RNFL. Conclusions: In middle-aged glaucoma patients with reduced RNFL we found no change in the optic radiation. An ascending degeneration to the optic radiation was not verifiable. In contrast, in older glaucoma patients with reduced RNFL the axonal integrity/ demyelination of the optic radiation was impaired. The impairment was significantly associated with loss of RNFL and ageing.

Nonarteritic anterior ischemic optic neuropathy (NAION) is the most common optic neuropathy in the elderly. Despite considerable research efforts, much remains unclear regarding the pathogenesis, risk factors and treatment options, with numerous contradicting reports and no consensuses among physicians. The more established risk factors include hypertension, diabetes mellitus, hypercholesterolemia, characteristic optic disc morphology, and perioperative visual loss. Several case reports suggested a link between certain phosphodiestrase-5 inhibitor erectile dysfunction medications and NAION, but this possible risk factor remains controversial. There is no established therapy for NAION, and many treatments have been proposed for the acute phase of the disease, of which some failed and others are considered experimental. This review summarizes the proposed pathogenesis theories, risk factors, diagnostic and imaging modalities and proposed treatment options for this blinding disease.

Introduction: Orbital cellulitis is a potential sight-threatening infection of the ocular adnexal structures posterior to the orbital septum. Acute bacterial sinusitis remains the most common cause of orbital cellulitis. Methods: A retrospective chart review was performed for patients admitted to The Royal Victorian Eye and Ear Hospital with a diagnosis of orbital cellulitis over a five-year period to July 2009. Results: 78 patients were identified for inclusion in the study, median age 42 years. Sinusitis was the most common predisposing factor, and was present in 52 patients (67%). All patients were treated with intravenous antibiotics. Surgical drainage was required for 28 patients (36%). Of these patients, 3 underwent endoscopic drainage only, 21 underwent open drainage, and 4 patients underwent a combination of open and endoscopic drainage. The most significant complication seen was persistent decreased visual acuity despite treatment, which was present in 5 patients (6%). Discussion: Orbital cellulitis remains a potentially sight-threatening infection that requires careful management, preferably by combined ENT and Ophthalmology teams. Surgery is reserved for those patients in whom signs of visual compromise are present initially, or in those who fail to improve with maximal medical management. Currently endoscopic drainage is not the most common surgical approach, however for selected patients it appears a safe comparable alternative.