Post on 24-Jan-2017
transcript
RetinaExamination&investigation
Dr_Mohamed ELShafie, assistant lecturer
Anatomy
• It is the senstive and inner most layer of the eye
• Derived from neural ectoderm• Extend from optic disc centrally to ora serrata
peripherally……..
Minute anatomy
Histologically formed of ten
layers
1 .The pigment epithelium2. The rods and cones3. The external limiting membrane
4 .The outer nuclear layer5. The outer plexiform layer6. The inner nuclear layer
7 .The inner plexiform layer8. The ganglion cells
9. The nerve fiber layer10.The internal limiting membrane
Blood Supply of the Retina
(1) The outer laminae, including the rods and cones and outer nuclear layer, are supplied by the choroidal capillaries
(2) The inner laminae are supplied by the central artery and vein.
central retinal vein ….drain into cavernous sinus
Fundus examunation
Direct ophthalmoscope• Uniocular• No stereopsis• Erect image• high magnification ×15• small field
Indirect ophthalmoscope• Binocular vision• Stereopsis• Inverted image• Low magnification ×5• Large field
Slit lamp biomicroscopically
With contact lensGoldman 3 mirror lens
With non contact lens• Biconcave(Hruby lens)
• Biconvex lens (+60&+78&+90)
Appearane of normal fundus
How to test the center of the retina = macula = macular function tests• Form sense: VA
• Colour sense:
Clear media: ishihara colour book
Opaque media:Ophthalmoscope coloured filters + light source
Some investigations
OCT
Flourescein angiography
Visual field examination
Conferentation test
• Compares peripheral vision with a tester who has normal peripheral vision
• 2 ft. apart, eye level
• Tester & client cover opposite eyes
• Tester advances finger in the periphery– Superiorly ( 50 degrees )– Inferiorly ( 70 degrees )– Temporally ( 90 degrees )– Nasally ( 60 degrees )
3_Perimetery
Visual field defect
• scotoma blind spot is physiological -ve scotoma
• Hemianopia involve one half of field(heterogenous& homonymous)
Fundus picture of some diseases• Diabetic Retinopathy
•VEDIO
PRP
Hypertensive Retinopathy
CRAO&CRVO
BRAO&BRVO
Embolization is the most common cause of obstruction to the retinal circulation, e.g. an embolus from a vegetation on one of the valves of
the heart in cases of subacute bacterial endocarditis
Degenerative changes within the arterial wall, e.g. arteriosclerosis or atherosclerosis.
Rhegmatogenous RD
Tractional RD
Retinitis pigmentosa
34
Retinoblastoma.
35
RETINOPATHY OF PREMATURITY
papilloedema
1ry optic atrophy
Glaucomatous optic atrophy