Retinal Vascular Disorders and Retinal Detachment MCQs

The management of a painful blind eye with end-stage glaucoma can include topical cycloplegia (anticholinergic agent) and a corticosteroid agent for comfort. A topical beta blocker may provide relatively little intraocular pressure lowering but may provide some increased comfort. Eyes with end-stage iris neovascularization and neovascular glaucoma have completely or near completely closed angles. A cholinergic agent, such as pilocarpine, will not successfully reduce intraocular pressure in these eyes and will often increase pain and inflammation. Reference: Parsons 22nd Edition/303

The nuclei of the Muller cells lie in the inner nuclear layer, whereas the nuclei of the photoreceptors lie in the outer nuclear layer. Reference : kurana 3/e,p. 46

RPE cells comprise the outer blood–retinal barrier; the inner blood– retinal barrier consists of the endothelium lining the retinal blood vessels. Reference : kurana 4/e, p. 40

Rhegmatogenous RD Pathophysiology The essential lesion is a rhegma (retinal break) through which the liquefied vitreous gains access to the retina. This liquefied vitreous accumulates beneath the neurosensory retina leading to RD. This is commonly seen in: High myopes: Peripheral retinal degenerations like lattice degeneration, holes and breaks with used liquefaction of overlying vitreous predispose to RD Trauma Aphakia Pseudophakia Reference: Yanoff and Duker 4th edition/648

Pneumatic retinopexy: In this procedure, the neurosensory retina is pushed towards the RPE by injecting an expansile gas in the vitreous cavity. The break is then sealed with laser. The gases commonly used are Sulphur Hexafluoride (SF6) and Perfluoropropane (C3F8) Reference: Yanoff and Duker 4th edition/648

Purtscher's retinopathy It is blockage of the retinal capillaries by emboli leading to multiple hemorrhages and cotton wool spots throughout the retina Causes are Acute pancreatitis Head and chest trauma. Thrombotic thrombocytopenic purpura Fat embolism Chronic renal failure Amniotic fluid embolism SLE Scleroderma Reference: Yanoff and Duker 6th edition/479

Retinal arteries are end arteries, branch dichomatously Artery : venous caliber ratio (AV ratio) = 2 : 3 Anastomosis at : lamina cribrosa Reference: parson's 22/e section IV chapter 20. pg 310-retinal vessels

Systemic hypertension causes hardening of the retinal arterioles. At the point where the retinal arterioles and venules cross, they are connected by a common adventitial sheath, which binds them together. The sclerotic arteriole causes a deformation of the venule's lumen, resulting in turbulent blood flow and a blood clot. Reference: Kanski's Clinical Ophthalmology, 8th Edition, Page Number-539.