Skip to main content

Cone-Rod Dystrophy an example of RPE atrophy due to cone-rod dystrophy

 

A patient presented with dyschromatopsia and photophobia with reduced vision to hand motion (HM)


Fundus image


Fundus exam shows golden sheen of the macula atrophic changes.

Fundus image showing cone-rod dystrophy golden sheen refelex with atrophic changes
Fundus image showing cone-rod dystrophy golden sheen refelex with atrophic changes 


Optical coherence tomography


OCT scan shows diffuse ellipsoid zone disruption and RPE atrophy, inducing increased reflectivity of the choroid. Although the fovea appears with normal contours, the boundaries between retinal layers are not clear.

OCT cross-section showing RPE atrophy with ellipsoid zone disruption in cone-rod dystrophy
OCT cross-section showing RPE atrophy with ellipsoid zone disruption in cone-rod dystrophy


Discussion


This patient has bad BCVA of HM due to cone-rod dystrophy, which can be autosomal recessive, dominant, or X-linked disease. They usually suffer from dyschromatopsia and photophobia, in late-stage cone-rod dystrophy can cause legal blindness.

Comments

Popular posts from this blog

Cellophane maculopathy

Caused by an epiretinal membrane, clinically, it appears as a sheen abnormal foveal reflex which features epiretinal membrane, due to inflammatory mediators and proliferation of glial cells secondary to a partial separation of posterior cortical vitreous. Fundus image shows cellophane maculopathy OCT features a hyperreflective band covering the inner retinal layers, causing minimal disturbance of inner retinal tissues. OCT cross-section shows epiretinal membrane  Cellophane maculopathy itself in individuals with good visual acuity may not need any interventions, but it is warranted to do a detailed peripheral retinal exam to rule out retinal tear or hole However, an epiretinal membrane may proliferate further and cause additional tangential traction. Thus, it may induce macular pucker or lamellar/pseudo hole and increase disturbance of inner retinal tissues, macular thickness, and reduction of vision. These patients may require pars plana vitrectomy to remove the epiretinal membrane an

RPE tear, and it's OCT features in a nutshell

RPE tear can occur in vascularized PEDs due to a complication of intravitreal AntiVEGF treatment, which causes a rapid contraction of CNVm, inducing traction on the RPE surface and shrinking of RPE surface. On OCT, the RPE rip will indent the retina with increased hyperreflectivity in contracted RPE with underlying shadowing hinders choroidal view in contrast to the area where RPE where it ripped of which only Bruch's membrane is visible and increasing the visibility of the underlying choroid. RPE tear Thus two opposite forces, the regression of CNVm and remaining attached RPE, other causes such as laser or spontaneous can occur. However, the AntiVEGF treatment continued despite the RPE tear. Please check  Clinical guidelines for ARMD  and  course of clinical changes in RPE

Sectoral retinitis pigmentosa

Sectoral retinitis pigmentosa is an autosomal dominant and usually associated with acceptable visual acuity.  The fundus examination shows pigment clumps and chorioretinal atrophy only in sectoral with almost normal optic disc configuration and vessel diameter. Fundus image showing Sectoral retinitis pigmentosa The sectoral retinitis pigmentosa symmetrical in both eyes Perimetry will show scotoma corresponding to the dispersion of pigmentary clumps. OCT shows outer retinal degeneration and RPE thining in the area of pigmentary clumps. Please check  Clinical guidelines in retinitis pigmentosa