OPTOM FASLU MUHAMMED

ANATOMYInner most layer

Thin, delicate & transparent membrane

Appears purplish red due to underlying vascular choroid

Retina extends from optic disc to ora serrata

Grossly divided in to two

Posterior pole & peripheral retina

Posterior pole & peripheral retina separated by retinal equator

Retinal equator is the imaginary line

POSTERIOR POLE Retina posterior to the retinal equator

It includes two areas optic disc & macula lutea

It is best examined by slit lamp indirect biomicroscopy & direct ophthalmoscopy

Cont…OPTIC DISC

- It is pink coloured

- Well defined circular area of 1.5mm in dia

- All retinal layers terminate except nerve fibres

- Nerve fibres pass through lamina cribrosa in to optic nerve

A depression seen in the disc called physiological cup

Central retinal artery & vein emerge through the centre of this cup

MACULA LUTEA It is also called yellow spot

It is deeper red

Situated in posterior pole temporal to optic disc

It is 5.5mm in dia

Fovea centralis is the central depressed part of the macula

Fovea centralis 1.50mm in dia

Most sensitive part of the retina

In its centre shinning pit called foveola

Foveola dia 0.35mm

Not contain any retinal capillaries

Also called foveal avascular zone

Surrounding fovea are parafoveal & perifoveal areas

FOVEA CENTRALIS No rods , cones are packed tightly

Foveola largely consists of cones & their nuclei covered by thin internal limiting membrane

Other retinal layers absent in this region

Cone axons arranged obliquely henle’s layer to reach the margin of the fovea

PERIPHERAL RETINA

Area bounded posteriorly by retinal equator & anteriorly by ora serrata

Best examined by indirect ophthalmoscopy

ORA SERRATAIt is the peripheral margin where retina ends

Here retina attached to vitreous & choroid

Pars plana extends anteriorly frm ora