1. Intravitreal injection of ganciclovir for treatment of CMV retinitis

2. Key Landmarks & Anatomy for safely performing injections
Limbus – the juncture of the cornea and sclera
Pars plana – the safe area to penetrate the wall of the eye with a needle, 4 mm from the limbus
Posterior ciliary vessels/nerves – the horizontal, 3/9 o’clock meridiens, the area to avoid when performing an injection

3. LIMBUS

4. limbus
Limbus: border between the sclera and cornea

5. PARS PLANA

6. When looking at the outside of the eye – where are the internal structures?
6mm
Zone of ciliary muscles
2.5mm
End of retinal tissue
(ora serrata)
Pars Plana
4mm - Safe distance from the limbus

7. View from inside the eye
Iris
Ciliary
Muscle zone
(pars plicata)
2.5 mm
4 mm
Pars plana
Safe injection line
6 mm
End of retinal tissue (ora serrata)

8. Ciliary body & pars plana summary
iris
Ciliary processes. Fibers (zonule)
attach from these to the lens
4.0 mm
Ciliary muscle contracts to change the
shape of the lens and focus at near
intraocular injections are safely performed thru the
pars plana, avoiding the retina

9. IDENTIFYING THE INJECTION SITE

10. Posterior ciliary arteries and nerves
There are 2 long posterior ciliary arteries and nerves, located temporally and nasally, starting in the mid-periphery, in the horizontal meridian
When examining the inside of the eye with the Indirect Ophthalmoscope, these are sometimes visible landmarks for 3 and 9 o‘clock meridian

11. 12
Retinal vessels
Fovea
Optic nerve 9 3
Long ciliary nerve
Retinal vessels
Vortex veins 6

12. Preferred injection site - OD12 9 3 7 6

13. Preferred injection site - OS12 9 3 4 6

14. Directing gaze: have the patient keep both eyes open, and give a target to look at

15. Measuring with the calipers
2 mm
4 mm

16. Measuring with the calipers

17. Injection approach 4mm from limbus Perpendicular approach
Towards center of eye or optic nerve (to avoid lens)

18. Injection example

19. Equipment Topical anesthetic proparacaine 0.5% or oxybuprocaine 0.4%
5% Betadine solution
Sterile cotton applicators
1ml syringe
30g needle if available, 27g or even 25g acceptable

20. Equipment (cont’d)
Standard calipers or tip of 1ml TB syringe (without needle)
Eyelid Speculum
Ganciclovir solution (50 mg/ml)
Mask and gloves

21. Preparation and dose
Dilute 500mg vial of lyopholized ganciclovir with 10 ml sterile preservative free water, giving a solution of 50mg/ml
Draw 0.1ml into syringe and flush back to make sure all air bubble are out, and syringe contains meds
Injection dose is 0.05ml of ganciclovir solution: 2.5mg dose of ganciclovir
Secure bottle of ganciclovir for future injections

22. Preparation and dose Ganciclovir 50mg/ml 500mg vial of lyopholized
Sterile
water
500mg vial of
lyopholized
ganciclovir
Ganciclovir
50mg/ml

23. Work with an assistant

24. Prepare everything you will need BEFORE you touch the patient

25. Intraocular injection is not difficult
BUT
It is a surgical procedure and must be done with exact care
if performed incorrectly, you can blind the patient
Devote 100% attention always