Refractive change following pseudophakic vitrectomy: a retrospective review

Background To assess the occurrence and magnitude of refractive change in pseudophakic eyes undergoing 20 gauge pars plana vitrectomy without scleral buckling and to investigate possible aetiological factors. Methods Retrospective case note review of 87 pseudophakic eyes undergoing 20 gauge pars plana vitrectomy for a variety of vitreo-retinal conditions over a three-year period. Anterior chamber depth (ACD) was measured before and after vitrectomy surgery in 32 eyes. Forty-three pseudophakic fellow eyes were used as controls. Results Eighty-seven eyes (84 patients) were included in the study. Mean spherical equivalent refraction prior to vitrectomy was -0.20 dioptres, which changed to a mean of -0.65 dioptres postoperatively (standard deviation of refractive change 0.59, range-2.13 to 0.75 dioptres) (p < 0.001). Sixty-one of the 87(70%) eyes experienced a myopic shift and 45(52%) eyes had a myopic shift of -0.5 dioptres or more. Mean fellow eye refraction was -0.19 dioptres preoperatively and -0.17 dioptres postoperatively (p = 0.14)(n = 37) Mean ACD preoperatively was 3.29 mm and postoperatively 3.27 mm (p = 0.53) (n = 32) and there was no significant change in ACD with tamponade use. Regression analysis revealed no statistically significant association between changes in anterior chamber depth, as well as a wide variety of other pre-, intra and postoperative factors examined, and the refractive change observed. Conclusion Significant refractive changes occur in some pseudophakic patients undergoing 20 g pars plana vitrectomy. The mean change observed was a small myopic shift but the range was large. The aetiology of the refractive change is uncertain

On the intersection of random rotations of a symmetric convex body

Let C be a symmetric convex body of volume 1 in ℝn. We provide general estimates for the volume and the radius of C ∪ U(C) where U is a random orthogonal transformation of ℝn. In particular, we consider the case where C is in the isotropic position or C is the volume normalized Lq-centroid body Zq (μ) of an isotropic log-concave measure μ on ℝn. © Cambridge Philosophical Society 2014.

Retinal Dystrophy in Long-Chain 3-hydroxyacyl-CoA Dehydrogenase Deficiency

[No abstract available

Vision testing in microsurgery subspecialties: Does it matter?

[No abstract available

Severe unilateral corneal melting after uneventful phacoemulsification cataract surgery

We present a rare case of severe unilateral corneal melt after uneventful phacoemulsification. A 38-year-old woman presented one week after uneventful phacoemulsification cataract surgery complaining of pain and blurred vision in her operated eye. Our differential diagnosis included peripheral ulcerative keratitis, Mooren's ulcer and herpetic keratitis. The patient was started on oral acyclovir and topical steroids. An extensive blood work-up was done to rule out autoimmune diseases. Purified protein derivative test demonstrated 15 mm of erythema. Because the clinical picture was progressing, the patient was started on triple anti-tuberculosis therapy. Despite treatment, the patient was complaining of excruciating eye pain that was relieved only with intramuscular prednisone injections. The corneal melt healed after approximately three months without any other intervention, leaving a 90 per cent thickness loss in its central area. Idiopathic corneal melt after uneventful phacoemulsification is a rare complication, which must be managed in a multidirectional treatment approach to prevent devastating corneal perforation

Unilateral Retinal Pigment Epithelium Dysgenesis: Long-Term Natural Evolution and Multimodal Imaging

Purpose: To present the natural course and describe the characteristic findings of a case of unilateral retinal pigment epithelium dysgenesis (URPED) and highlight the optical coherence tomography angiography characteristics of this rare fundus pattern. Methods: Case report. Results: A 52-year-old male was referred 8 years ago to our clinic due to a distinctive unilateral lesion in his left fundus, of which he was aware from early adulthood. Clinical evaluation revealed an irregularly shaped patch of retinal pigment epithelium atrophy surrounding his left optic nerve, with a characteristic scalloped border and with severe distortion of the overlying retinal and vascular tissue. Retinal pigment epithelial hyperplasia was noted in the margin as well as in distinct lacunae clustered around the periphery of the lesion. Right fundus examination was normal. The patient was diagnosed with URPED and was followed annually with multimodal imaging ever since. No choroidal neovascularization or other complication was noted. However, the lesion appeared to slowly but steadily grow to eventually affect the foveal region causing severe visual loss. Best corrected visual acuity was 20/40 at baseline and 20/200 at last follow-up 8 years after the original diagnosis. Conclusion: URPED is a rare retinal disease with unique clinical characteristics that can progress relentlessly even in the absence of secondary complications. © 2019 S. Karger AG, Basel

Pathogenetic mechanisms in combined cilioretinal artery and retinal vein occlusion: a reappraisal

We examined nine patients who presented cilioretinal artery occlusion (CLRAO) associated with retinal vein occlusion (RVO). CLRAO was probably secondary to the raised intraluminal resistance consequent to the RVO in patients showing initially a delayed filling of the cilioretinal artery in fluorescein angiography. Interestingly, these patients presented an ophthalmoscopically more severe form of RVO and had systemic predisposing factors for a RVO. In patients presenting a physiological perfusion of the cilioretinal artery in fluorescein angiography, RVO was a self limited disease and etiologic factors were not found. This may suggest that in these patients the CLRAO probably occurred simultaneously with the RVO after a decrease in perfusion pressure in both retinal and cilioretinal arterial systems. In this combined vaso-occlusive retinopathy the vulnerability of cilioretinal arteries can be explained either by the absence of autoregulation or by their lower perfusion pressure gradient in comparison with retinal arteries