Neuroradiology Unit, S P Institute of Neurosciences,Solapur,Maharashtra, INDIA
Sunday, 21 August 2011
Retinal Vs Choroidal detachment MRI
Differentiation between Retinal and Choroidal detachment possible on MRI based on configuration of collection.
Retinal detachment is accumulation of blood or fluid in sub retinal space between two layers of retina, the inner sensory layer and outer pigmentary epithelium. Configuration of collection cresent shaped or V shaped on axial sections, limbs of V represent detached leaves of retina converging towards optic disc represent the apex of V. Collection anteriorly extend upto ora serrata represent anterior limit due to normal anterior attachment of retina.
Choroidal detachment is accumulation of blood or fluid in supra choroidal space between choroid and sclera, so collection extend circumferentially along the entire supra choroidal space , configuration is lentiform shaped along medial as well as lateral wall of globe, choroid bulging medially on either side giving so called kissing choroid sign. Anteriorly extend upto ciliary bodies and posterior limit formed by anchoring effect of short posterior ciliary arteries and nerves preventing convergence of detached choroidal leaves to a single point.