Optic Nerve

OPETIC NERVE

SET BY: NOFEL SALEEM ASSWIELMEDICAL STUDENT ,ADEN UNIVERSITY THIRD YEAR 2013/2014

E-mail :166 .Nofel @gmail com @nasswiel facebook/nasswiel

Symptoms & Signs in Clinical Medicine

Anatomical points

Impressions of light >> optic nerve >> optic chiasma >> optic tracts >> lateral geniculate bodies >> optic radiation >> occipital cortex

optic tracts >> pretectal area (pupillary Reflex)

Medial parts of optic tracts (communication) between optical system & ocluomotor nuclei.

Optic paths & Surrounding structure

Examination of the optic nerve and its connection

Visual Acuity

Near vision - Reading from a book

Far vision- Snellen chart.- Ishihara charts

Snellen chart

Ishihara charts

Ophthalmoscopic Examination Retinae

Optic discs- Color.- Margin- Counter- Crescent- Distribution of veins.

- Examination of the Eye & Vision OSCE Guide

Normal optic disc

Papilloeodema

Definition ,

hydrostatic Non-inflammatory swelling.

Optic disc or nerve head.

Associated with ↑ Intracranial pressure

Papilloeodema

Causes

1. Raised Intracranial Pressure>- Space-occupying lesions- Malignant HTS.- Chronic carbon-dioxide retention.-Occlusion of :retinal veins cavernous sinus-Other cause.

Papilloeodema

Pathogenesis Subarachnoid space. Retinal vessel. Raised Pressure. The inflow & outflow

Foster kennedy syndrome

Seen in patients with frontal lobe / olfactory lobe tumors, meningiomas of olfactory groove / sphenoidal wing.

characterized by optic atrophy on the side of the tumor (direct pressure on the nerve) papilledema on the opposite side (raised ICT).

Papilloeodema

Engorgement of the veins blurring of disk margin. Disappearance of blood vessel.

Optic Neuritis Definition

- Inflammation or demyelination - At any point of the optic nerve.

Near the disc >> optic neuritis behind the eyeball(lamina cribrosa) >>

retrobulbar neuritis. Causes

- Multiple Sclerosis- Meningitis - Avitaminosis .

Optic Neuritis

Central scotoma Oedematous disc>> less swelling Red coloration of the disc Inflammatory exudates > cloudy disc

Founds Signs of Optic Neuritis

Optic Atrophy

Definition - Damage of the optic nerve.

Causes - Optic Neuritis - Papilloeodema- Trauma .- Glaucoma- Ischaemia- Familial

Optic Atrophy Pallor of the optic

disc. Loss of visual

acuity.-sever optic neuritis, vascular occlusion>> Rapid visual failure. - Other condition >> slow & progressive

1 Hypertensive

2 Diabetic

The Retinopathies

Hypertensive Retinopathy Classification

- According to - appearance. - life prognosis.

GRADE I HTR

Narrowing of the vessel

Age- related

GRADE II HTR

Marked variation of the caliber of the vessel.

Veins is kinked, the peripheral caliber is engorged

Age- related

GRADE III HTR

Addition of Flame shaped or round retinal hemorrhages & cotton wool spots, hard exudates.

GRADE IV HTR

All changes of grade 3

Addition of papilloedema

Increase hemorrhages and exudates

Diabetic Retinopathy

Definition Progressive dysfunction of the retinal blood

vessels caused by chronic hyperglycemia. DR can be a complication of diabetes type

1 or diabetes type 2. Initially, DR is asymptomatic, if not treated

though it can cause low vision and blindness.

Diabetic Retinopathysymptoms

Diabetic retinopathy is asymptomatic in early stages of the disease

As the disease progresses symptoms may include Blurred vision Floaters Fluctuating vision Distorted vision Dark areas in the vision Poor night vision Impaired color vision Partial or total loss of vision

Diabetic Retinopathy

Retina is thickly with minute red dots (micro aneurysms)

Microaneurysms

Diabetic Retinopathy

Next :larger blot & dot hemorrhages appear

Then:waxy-looking exudates with harder edges.

Microaneurysms

Hard exudates

Diabetic Retinopathy

Larger hemorrhages appear with irregular veins.

New-formed vascular plexuses .veins loops and coils(may protruded into the vitreous)

Hard exudatesNeovascularization

Blot hemorrhage

Set by :Nofel Saleem Asswiel