Downloaded 26 times
Uploaded byAshith Tripathi
Retina - Congenital anomalies and RD by Ashith Tripathi
The document discusses congenital anomalies of the retina including coloboma, congenital pigmentation, albinism, and retinal detachment, detailing their causes, clinical features, and classifications. It also describes the types of retinal detachment: rhegmatogenous, tractional, and exudative, along with their etiologies and treatment options. The content is aimed at providing comprehensive knowledge about retinal conditions for students in optometry.
More Related Content
Similar to Retina - Congenital anomalies and RD by Ashith Tripathi
Retina - Congenital anomalies and RD by Ashith Tripathi
- 1. Retina – congenital anomalies and RD Guidedby – Gaurav sir ( Faculty at UPUMS, Saifai, Etawah) Represented by – Ashith Tripathi ( B. Optometry 3rd year student)
- 2. Retina – The retinais light sensitive tissue, that lines the inside of eye. The neurosensory retina is transparent, the background colour being provided by retinal pigmented epithelium and vascular choroid. History – – first describe by HEROPHILUS – Named by – RUFUS – Kepler introduced the concept of the retina as the primary photoreceptor tissue of the eye.
- 3.
- 6. Retinal embryogenesis – Theeyeball starts to develop from neuroectoderm around the third week of fetal life. – Formation of optic pits and then optic vesicles to optic cup. – The optic cup forms a fold inferiorly and ventrally to form the ‘embryonic fissure’ through which the mesenchymal and vascular tissues enter the globe. – The inner layer of optic cup develops into the retina, and the outer layer develops into the retinal pigmented epithelium. – Cones – 5 months – Rods – 7 months
- 8. Congenital abnormalities ofthe retina Coloboma – – white defect, the sclera is directly visible due to the absence of normal retina and retinal pigment epithelium. – Not progressive – Difficult to treat
- 10. Congenital pigmentation ofthe retina – Small, oval, grey spots or groups of polygonal greyish – black spots are occasionally seen in the retina in routine examination of the fundus. – They are flat, lie below the vessels, and remains unchanged indefinitely. – They are congenital and due to heaps of retinal pigment.
- 11. Medullated nerve fibres –The medullary sheaths of the fibres of the optic nerve normally appear behind the lamina cribrosa. Occasionally, patches of fibres becomes myelinated before they have passed through the lamina cribrosa. – They appear opthalmoscopically as white patches. – Usually the patches are contiguous with the disc; occasionally they are isolated, but rarely far from the disc. – The retinal vessels are covered in places by the opaque fibres. – When present, blind spot is enlarged, or a scotoma is present corresponding with the position of the patch. – Very rarely, the patch is large and involves the macula, so central vision is abolished.
- 13. Albinism – Originated fromlatin word “albus” meaning white – It represents a set of inherited conditions characterized by absent or decreased tissue melanin in conjunction with characteristic ocular and visual pathway anomalies. – Decreased skin and hair pigment Clinical features – – Iris transillumination – Pendular nystagmus – Foveal hypoplasia – Strabismus – Photophobia – Refractive error – Poor vision
- 15. Retinal detachment – Retinaldetachment is the separation of neurosensory retina proper from the pigment epithelium. Classification – – Clinico – etiologically retinal detachment can be classified into three types : 1. Rhegmatogeneous or primary retinal detachment 2. Tractional retinal detachment 3. Exudative retinal detechment
- 17. Rhegmatogenous or primary retinalDetachment – It usually associated with a retinal break ( hole or tear ) through which subretinal fluid (SRF) seeps and separates the sensory retina from the pigmentary epithelium. – It is commonest type of retinal detachment Etiology – – Predisposing factors includes – – Age – Sex – Myopia – Aphakia and pseudophakia – Retinal degenerations – Trauma – Senile posterior vitreous detachment ( PVD )
- 18. Pathogenesis – Senile acute posterioir vitreous detachment (acutePVD) Predisposing retinal degenerations Aphakia (endodenesis ) Retinal break The degenerated fluid vitreous seeps through the retinal break and collects as subretinal fluid (SRF) between the sensory retina and pigmentary epithelium. Retinal detachment Trauma
- 19. Clinical features Prodromal symptomsinclude : – Dark spots ( floaters ) in front of the eye – Photopsia (sensation of flashes of light ) Symptoms of detached retina are as follows: – Localised relative loss in the field of vision – in early stage – Sudden appearance of a dark cloud or veil in front of eye – Sudden painless loss of vision
- 20. signs – Marcus Gunnpupil is present in eyes with extensive RD – Plane mirror examination or DDO reveals an altered red reflex in pupillary area – Freshly detached retina gives grey reflex instead of normal or pink reflex and is raised anteriorly – Visual field charting reveals scotomas – Ultrasonography confirms the diagnosis. Complications – Include proliferative vitreoretinopathy (PVR), complicated cataract, uveitis and phthisis bulbi.
- 21. Treatment – Basic principleand step of RD surgery are sealing of retinal breaks, reducing the vitreous traction on the retina, and flattering of retina by draining of subretinal fluid. – Sealing of retinal breaks – Drainage of SRF – Maintenance of chorioretinal apposition is required for at least a couple of weeks.
- 22. Exudative or solidretinal detachment – It occurs due to retina being pushed away by a neoplasm or accumulation of fluid beneath the retina following inflammatory or vascular lesions. Etiology – common causes of exudative retinal detachment can be grouped as under: – Systemic disease – include: toxaemia of pregnancy, renal hypertension, blood dyscrasias and polyarteritis nodosa. – Ocular disease – include 1. Congenital abnormalities such as nanopthalmos, optic pit, choroidal coloboma and familial exudative vitreoretinopathy (FEVR)
- 23. 2. Inflammations suchas Harada’s disease, sympathetic opthalmia, posterior scleritis, and orbital cellulitis. 3. Vascular disease – such as central serous retinopathy and exudative retinopathy of coats. 4. Neoplasm – retinoblastoma , metastatic tumours of choroid 5. Choroidal neovascularization may also cause exudative retinal detachment.
- 24. Clinical features Exudative retinaldetachment can be differentiated from a simple primary detachment by: – Absence of photopsia, holes/tears, folds and undulations. – The exudative retinal detachment is smooth and convex – Pattern of retinal vessels may be disturbed occasionally, due to presence of neovascularization on the tumour summit. – Shifting fluid characterised by changing position of the detached area with gravity is the hallmark of exudative retinal detachment. – On transillumination test a simple detachment is opaque.
- 25. Investigations – Ocular andsystemic examination should be carried out thoroughly. – B- scan ultrasonography may help delineate the underlying cause. – FFA may show source of fluid – CT scan and/ or MRI useful, specially in case of intraocular tumours. Treatment – – Treatment should be for the causative disease. – Enucleation is usually required in the presence of intraocular tumours.
- 26. Tractional retinal detachment –It occurs due to retina being mechanically pulled away from its bed by the contraction of fibrous tissue in the vitreous ( vitreoretinal tractional bands ) Etiology – – TRD is associated with the following conditions; – Proliferative diabetic retinopathy – Retinopathy of prematurity – Plastic cyclitis – Sickel cell retinopathy – Vitreomacular traction syndrome – Retinal dysplasia
- 28. Clinical features – Presenceof vitreoretinal bands with lesions of the causative disease. – Retinal breaks are usually absent and configuration of the detached area is concave. – Highest elevation of the retina occurs at sites of vitreoretinal traction. – Retinal mobility is severely reduced and shifting fluid is absent. Treatment – – Surgery is difficult and require pars plana vitrectomy to cut the vitreoretinal traction bands and internal tamponade with either a long – acting gas or silicon oil. – Prognosis in such cases is usually not so good.
- 30. References – Person's Diseaseof the Eye - by Ramanjit sihota – Comprehensive Opthalmology - by A. K. Khurana – Wikipedia – Google for pics