Pseudophakia

Pseudophakia
IOL implantation on phakic eye
signs

1. PSEUDOPHAKIA SAVEENA PAUDEL BSC OPTO METRY

2. PHAKIA – The condition of presence of crystalline lens APHAKIA – Absence of lens from pupillary regions P SEU DOPHAKIA – Presence of artificial lens; here the word ‘pseudo’ means false.

3. INTRAOCULAR LENS An Intraocular lens is a lens implanted in the eye used to treat cataract or aphakic eye. The most common IOL for cataract is known as pseudophakic IOLs. The power of an IOL to be implanted is calculated by considering keratometric reading and axial length of the eyeball. Intra oc ular lens is a lens implanted in the eye used to treat cataract or aphakic eye.The most common IOL for cataract is pseudophakic IOLS. The power of an IOL to be implanted is calculated by considering the keratometric reading and axial length of the eye ball.

4. CALCULATION OF IOL POWER Most common method is SRK I (Sanders Retzlaff and Kraff) P = A- 0.9K- 2.5L P = Power of IOL A = Constant specific for each lens L = Axial length in mm K = Average keratometry in dioptres.

5. Types of IOLs Anterior chamber IOLs Iris-supported lens Po sterior chamber lens Scleral fixator IOLs

6. Anterior chamber IOLs (Angle supported phakic IOLs ) IOL placed in Anterior chamber of eye . These are used to treat myopia. These are concave lenses and are monofocal. May involve negative impact on the corneal endothelial lining.

7. Posterior chamber IOLs (Angle supported phakic IOLs) It consist of securing the IOL in the ciliary sulcus. It is most done for cataract surgery. IOL is attached to ciliary muscles and help move the IOL as if they are natural crystalline lenses. They allow multifocal lenses.

8. Iris-supported lens IOL is supported by iris as in natural crystalline lens It have safe distance from corneal endothelium. One size fix all Scleral fixated IOLs Most invasive technique.

9. Refractive Status Of Pseudophakic Eye EMMETROPIA CONSECUTIVE MYOPIA CONSECUTIVE HYPERMETROPIA ASTIGMATISM

10. EMMETROPIA It is most ideal situation. It is produced when the power of implantation is exact. They require plus lens for near vision.

11. CONSECUTIVE MYOPIA It usually occurs when IOL implant overcorrects the refraction of eye. Such patients require glasses to correct myopia for distance vision It may require or may not require glasses for near vision depending upon the degree of myopia.

12. Consecutive Hypermetropia It develops when the underpower IOL is implanted. Such patient’s require plus glasses for distance vision and additional +2 to +3 D for near vision.

13. Astigmatism Varying degree of surgery-induced astigmatism (SIA) is also present.

14. Signs of pseudophakia Limbal scars may be seen. Anterior chamber slightly deeper than normal. Mild iridodonesis. Purkinje image test shows four images. Pupil is black in color, shinning reflex is seen when light reflex is thrown in pupillary area. Presence of IOL is confirmed when exmined under magnification after dilating the pupil. Visual status and refraction will vary, depending upon the power of IOL implanted

15. Thank you