Fundus examination

Fundus examination

1. FUNDUS EXAMINATION Soumitra das

2. METHODS OF EXAMINATION DIRECT OPHTHALMOSCOPY INDIRECT OPHTHALMOSCOPY INDIRECT SLIT LAMP BIOMICROSCOPY

3. Why do we dilate pupils?

4. PUPILLARY DILATION Combination of phenylephrine [2.5 %] & tropicamide [1 %] then eyes closed Dilation attained = 15-30 min Normal reactivity = 4 - 8 hrs Conditions which to avoid : iris supported lens shallow AC

5. D IRECT OPHTHALMOSCOPY

6. Viewing ocular media Observe red reflex Look for media opacities Cataracts Corneal scars Large floaters Right eye to right eye Left eye to left eye

7. An erect upright virtual image Magnification = 15 x Field of view = 5 degrees No stereoscopic view Several plus and minus dial up lenses Structures - optic nerve, blood vessels of posterior pole fovea

8. Advantages Portable Easy to use Upright image Magnification  15x Can use w/o dilation Disadvantages Small field of view Lack of stereopsis Media opacities can degrade image

9. - retinal arterioles - exudate retinal haemorrhage edema microaneurysm attached retina - vitreous opacity hole /break vitreous bleed - Retinal venules - pigmentation detached retina detached choroid outine of break - ora serrata / drusen hyperpigmentation Colour codes :

10. Vitreoretinal chart

11. Indirect ophthalmoscopy

12. condenser Inverted Fundus Image

13. An inverted reverse real image Magnification = 2 to 4 X Field of view = 40 to 50 degrees Optimal working distance = 40 to 50 cms Good illumination & stereopsis Ease of use with scleral indentor Lenses from 14 to 30 D range

14. Headset correctly positioned Optimizing viewing distance

15. Monocular or binocular Advantages: Wide field of view Binocular instruments provide stereopsis Disadvantages: Requires more skill Decreased magnification (3x) Requires dilation Inverted image

16. Indirect slit lamp biomicroscopy

17. Field of View & Mag: FOV <indirect but >direct varies w/lens & slit lamp mag Inverted image Stereopsis Dilated pupil Requires skill

18. Slit-Lamp BIO An inverse real reversed image with hand held lenses Field of view = 30 to 40 degrees Lens power = + 78 or + 90 D , other lenses= + 60 to 132 D Magnifying knob to 10 X or 16 X

19. Optic disc DISC: DIAMETER – 1.5mm [1 disc diameter] COLOR – Pale pink SHAPE – Circular EDGES – Regular TERMINATION OF ALL LAYERS EXCEPT NFL CUP: C/D ratio – 0.3 to 0.4

20. Vessels RETINAL SYSTEM : CENTRAL RETINAL ARTERY AND CENTRAL RETINAL VEIN 4 major branches Arterioles, Venules Capillaries CILIARY SYSTEM : POST.CILIARY ARTERIES Choriocapillaries

21. MACULA Specialised region of retina Diameter – 5.5 mm Location – 2 DD - temporal margin of disc Color – Yellow; deep pigmented 4 zones : Foveola -0.35 mm Fovea - 1.50 mm Parafovea Perifovea Retinal vessels Cilioretinal artery

22. Glaucoma

23. Optic Disc swelling

24. AION

25. Optic disc atrophy

26. Mylinated nerve fibre

27. RP

28. DR

29. HR

30. THANK YOU