*Clinico-etiologically retinal detachment can be classified into three types:
1. Rhegmatogenous or primary retinal detachment.
2. Exudative or Solid retinal detachment
3. Tractional retinal detachment
*Tractional and exudative type of retinal detachment are examples of secondary retinal detachment.
1. RHEGMATOGENOUS retinal detachment : It is usually associated with a retinal break (hole or
tear) through which subretinal fluid (SRF) seeps and separates the sensory retina from the pigmentary epithelium. Predisposing factors of Rhegmatogenous retinal detachment are :
- Though age is no bar, it is most common in the 40-60 years age group
- More common in males (M:F = 3:2)
- About 40% cases of Rhegmatogenous RD are myopic.
- This condition is more common in aphakes than phakes.
- Several retinal degenerations predispose to Rhegmatogenous Retinal detachment. They are :
a. Lattice degeneration
b. Snail track degeneration
c. White-with-pressure and White-without-or-occult pressure
d. Acquired retinoschisis
e. Focal pigment clumps
-Trauma may also act as a predisposing factor
- Senile posterior vitreous detachment (PVD) - association seen in many cases.
2. EXUDATIVE (SOLID) Retinal detachment : It occurs due to the retina being pushed away by a neoplasm or accumulation of fluid beneath the retina following inflammatory or vascular lesions. Causes of exudative retinal detachment are :
3. 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). The causes of tractional retinal detachment are :
- Post-traumatic retraction of scar tissue especially following penetrating injury
- Proliferative Diabetic retinopathy
- Proliferative Retinopathy in Eale's disease
- Post-haemorrhagic retinitis proliferans
- Plastic cyclitis
- Retinopathy of prematurity
- Sickle cell retinopathy
Parson's Diseases of the Eye
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