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PROBLEMS OF APHAKIA & IOL Maj M. Ahsan Mukhtar FCPS, FRCS (Glasg) CLASSIFIED EYE SPECIALIST REGISTRAR VITREO-RETINAL SURGERY.

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Presentation on theme: "PROBLEMS OF APHAKIA & IOL Maj M. Ahsan Mukhtar FCPS, FRCS (Glasg) CLASSIFIED EYE SPECIALIST REGISTRAR VITREO-RETINAL SURGERY."— Presentation transcript:

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2 PROBLEMS OF APHAKIA & IOL Maj M. Ahsan Mukhtar FCPS, FRCS (Glasg) CLASSIFIED EYE SPECIALIST REGISTRAR VITREO-RETINAL SURGERY

3 OBJECTIVES   Enlist common problems of aphkaia   Briefly describe the mechanism / physics of these problems   Know basics of intraocular lenses

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7 PROBLEMS OF APHAKIA   Relative spectacle magnification (RSM)   Anisometropia in unilateral aphakia   Aberrations   Heavy lenses (glasses)   Visual field limitation   Loss of ultra-violet protection   Other problems   Cystoid Macular edema   Retinal Detachment   Increase In Proliferative Diabetic Retinopathy   Amblyopia in children with unilateral aphakia

8 PROBLEMS OF APHAKIA   Relative spectacle magnification (RSM)   Anisometropia in unilateral aphakia   Aberrations   Heavy lenses (glasses)   Visual field limitation   Loss of ultra-violet protection   Other problems   Cystoid Macular edema   Retinal Detachment   Increase In Proliferative Diabetic Retinopathy   Amblyopia in children with unilateral aphakia

9 RELATIVE SPECTACLE MAGNIFICATION The ratio between the corrected and uncorrected image size Image is 33% larger in corrected aphakia Patient may misjudge distances Actual VA of an Aphakic reading 6/9 is approx 6/12

10 RELATIVE MAGNIFICATION AND IMAGE SIZE SOLUTION Intra-ocular lens Contact lens Isiekonic lens Corneal procedures

11 PROBLEMS OF APHAKIA   Relative spectacle magnification (RSM)   Anisometropia in unilateral aphakia   Aberrations   Heavy lenses (glasses)   Visual field limitation   Loss of ultra-violet protection   Other problems   Cystoid Macular edema   Retinal Detachment   Increase In Proliferative Diabetic Retinopathy   Amblyopia in children with unilateral aphakia

12 ABERRATIONS IMAGE DISTORTION troublesome to the newly aphakic patients Straight lines appears curved except when viewed through a very small axial zone of lens

13 ABERRATIONS RING SCOTOMA The prismatic power of the more peripheral parts of a spherical lens

14 ABERRATIONS JACK-IN-THE-BOX The direction of the scotoma changes as the patient moves his eyes, and objects may appear out of the scotoma or disappear into it. SOLUTION Tell the patient to move his head instead of moving eyes while wearing aphakic glasses

15 PROBLEMS OF APHAKIA   Relative spectacle magnification (RSM)   Anisometropia in unilateral aphakia   Aberrations   Heavy lenses (glasses)   Visual field limitation   Loss of ultra-violet protection   Other problems   Cystoid Macular edema   Retinal Detachment   Increase In Proliferative Diabetic Retinopathy   Amblyopia in children with unilateral aphakia

16 HEAVY GLASS LENSES Use plastic lenses

17 PROBLEMS OF APHAKIA   Relative spectacle magnification (RSM)   Anisometropia in unilateral aphakia   Aberrations   Heavy lenses (glasses)   Visual field limitation   Loss of ultra-violet protection   Other problems   Cystoid Macular edema   Retinal Detachment   Increase In Proliferative Diabetic Retinopathy   Amblyopia in children with unilateral aphakia

18 VISUAL FIELD LIMITATION SOLUTION Ask Patient to move head instead of moving eyes while wearing aphakic glasses

19 PROBLEMS OF APHAKIA   Relative spectacle magnification (RSM)   Anisometropia in unilateral aphakia   Aberrations   Heavy lenses (glasses)   Visual field limitation   Loss of ultra-violet protection   Other problems   Cystoid Macular edema   Retinal Detachment   Increase In Proliferative Diabetic Retinopathy   Amblyopia in children with unilateral aphakia

20 LOSS OF ULTRA-VIOLET PROTECTION SOLUTION Intra-ocular lens with UV protection Glasses with UV protection

21 PROBLEMS OF APHAKIA   Relative spectacle magnification (RSM)   Anisometropia in unilateral aphakia   Aberrations   Heavy lenses (glasses)   Visual field limitation   Loss of ultra-violet protection   Other problems   Cystoid Macular edema   Retinal Detachment   Increase In Proliferative Diabetic Retinopathy   Amblyopia in children with unilateral aphakia

22 Cystoid Macular edema Retinal Detachment Increase In Proliferative Diabetic Retinopathy Amblyopia in children with unilateral aphakia Occlusion therapy IOL Contact lenses OTHER PROBLEMS DUE TO APHAKIA

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24 INTRA OCULAR LENSES

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26 The optic (the central refracting element) The heptics

27 IOL MATERIAL Optic Polymethylmethacrylate (PMMA) Silicon Acrylic (hydrophillic and hydrophobic) Hydrogel Heptics Polypropylene (3 piece) Same material as optics (1 piece)

28 IOL DESIGN

29 TYPES OF IOL AC IOLIris claw LensPC IOL

30 Monofocal IOL Multifocal IOL Toric Accomodative IOL TYPES

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33 PLACEMENT OF IOL IN EYE The posterior chamber (PC IOL) capsular bag Sulcus The anterior chamber (AC IOL) Iris / pupil supported Angle supported

34 AC-IOL

35 PC IOL PC IOL in Capsular bag

36 RIGID VS FOLDABLE IOL’S Rigid PMMA One piece to facilitate maximal stability and fixation Foldable Silicone IOLs: have lower rates of posterior capsular opacification than PMMA IOLs Acrylic IOLs Hydrogel IOLs: have higher water content Collamer IOLs : are a mixture of collagen and hydrogel (newly developed)

37 ADVANTAGES OF IOLs All problems of aphakia gone Broader field of view Lesser problem of image magnification Binocularity is maintained

38 DISADVANTAGES OF IOLS Problems of accommodation Chances of dislocation into the vitreous UGH syndrome with AC-IOL Endothelial decompensation

39 THANK YOU


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