Dr Laltanpuia Chhangte, profile picture
Uploaded byDr Laltanpuia Chhangte
21,686 views

RECENT ADVANCES IN INTRAOCULAR LENS

1) Intraocular lenses (IOLs) are artificial lenses implanted during cataract surgery to replace the clouded natural lens and correct vision. 2) IOLs have evolved over generations from rigid PMMA lenses to modern foldable designs made of silicone, acrylic, or hydrogel materials. 3) IOLs can be mono-focal, providing a single vision correction, or multi-focal, attempting to provide both near and distance vision without glasses. Accommodating IOL designs also aim to restore the eye's ability to focus at different distances.

Embed presentation

RECENT ADVANCES IN IOLS Dr. Laltanpuia Chhangte GMC ,HALDWANI
What is intraocular lens? • An artificial lens implanted in the eyes • Replaces the crystalline lens • To correct the optical power of the eyes following:- Lens being clouded by cataract Refractive surgery
Primary vs secondary implantation • Primary implantation – use of IOLs during surgery for cataract • Secondary implantation – implantation of IOL to correct aphakia in a previosly operated eye
Parts of an IOL • OPTIC Part of the lens that focuses light on the retina. • HAPTIC Small filaments connected to the optic that hold the lens in place in the eye HAPTEN OPTIC
HISTORY OF IOL • K
THE FIRST IOL!! • PMMA made lens – 45 year old female after performing extracapsular cataract extraction • Disc shaped bi-convex design • Site- posterior chamber • First generation IOL
EVOLUTION OF IOLs 1. First generation IOLs • Ridley lenses • Disadvantages – posterior dislocation poor surgical technique 2. Second generation IOLs • Rigid and semi-rigid anterior chamber IOLs • Advantages – reduce posterior dislocation • Disadvantage – corneal decompensation UGH syndrome
3. Third generation IOLs • Iris supported lens • Advantages- less corneal decompensation • Disadvantages – iris chaffing pupillary distortion c/c inflammation cystoid macular edema
4. Fourth generation IOLs • Modern anterior chamber lens • Flexible loops and multiple point fixation • Advantages – more stable, better design, less complications • Disadvantages – anterior chamber is not the physiological site for IOL
5. Fifth generation IOLs • PMMA lenses • Foldable and small incision lenses
MATERIALS USED FOR INTRAOCULAR LENSES Optic materials 1.Non-foldable-rigid IOL • Poly-methyl methacrylate(PMMA) Water content <1% Refractive index 1.49 Usually single piece May be penetrated by aqueous humor known as ‘glistenings’ (very rare) 2.Flexible IOLs • Silicones • Hydrophobic acrylic • Hydrophilic acrylic • Hydrogel • Collamer
Features of IOL
INTRAOCULAR LENS DESIGN • Single piece / monobloc • Plate haptic / open loop haptics • Angulated / planar haptics • Edge design • Optic design
Different types of haptic angulation relative to the plane of optic:- For posterior chamber lens:- • 100 anterior angulation to keep the optic part away from the pupil. For anterior chamber lens:- • Posteriorly angulated lens to vault the intraocular lens away from the pupil
ANGULATED HAPTICS ALLOW FOR ADEQUATE PUPILLARY CLEARANCE AND ADHESION TO THE POSTERIOR CAPSULE
………
Square, truncated optic edge
Suitable position for implanting IOL in eye • Best placed in posterior chamber in the capsular bag.
ADVANTAGES OF IN-THE-BAG PLACEMENT • Proper anatomical site • Symmetrical loop placement • Intraoperative stretching or tearing of zonules is avoided • Minimal magnification (<2%); (20-30% aphakic glasses, 7-12% aphakic contact lens, ACIOL 2-5% ) • Low incidence of lens decentration and dislocation • Maximal distance from the posterior iris pigment epithelium, iris root, and ciliary processes • Reduced posterior capsular opacification
POSITIONING OF IOL 1. Posterior chamber implantation • Ciliary sulcus fixation • In the bag fixation • Scleral fixation Eg:- modified C loop type IOL
In-the-bag fixation
OTHER POSITIONS: • Posterior capsule tear • zonular dialysis
Ciliary sulcus fixation
Scleral IOL
2. Anterior chamber implantation • Angle supported IOLs • Iris fixated e.g Kelman multiflex type IOL
3. Iris- fixated lens • Fixed on the iris with claws,loops or sutures • Eg- Singh and Worst’s iris claw lens
BASED ON OPTICAL CORRECTION 1. Mono-focal intraocular lens • Lens with uni-focal power • This common IOL type has been used for several decades . • Mono-focals are set to provide best corrected vision at near, intermediate or far distances. • Most people who choose mono-focals have their IOLs set for distance vision and use reading glasses for near activities. • Some who choose mono-focals decide to have the IOL for one eye set for distance vision, and the other set for near vision, a strategy called "monovision."
…….. • The brain adapts and synthesizes the information from both eyes to provide vision at intermediate distances. People who regularly use computers, PDAs or other digital devices may find this especially useful. • Individuals considering monovision may be able to try this technique with contact lenses first to see how well they can adapt to monovision. • Those who require crisp, detailed vision may decide monovision is not for them. People with appropriate vision prescriptions may find that monovision allows them see well at most distances with little or no need for eyeglasses.
2.Multifocal IOLs • Single IOL with two or more focal points • Refractive • Diffractive • Combination of both • Simultaneous vision lenses • Pseudo-accommodation
Multifocal IOLs • Multifocal iols have the advantage of providing patients with functional vision at near ,far and at intermediate distances. • Patients can have a traditional monofocal iol with a refractive target of emmetropia,mild myopia,or monovision(1 eye distance,1eye near) • The Array (AMO),Santa ana CA multifocal silicone PCIOL was the first multifocal IOL to be granted fda approval in US. • Three mutifocal lenses are currently FDA approved for use after cataract extraction: • ReZoom lens(AMO),The Acrysof ResTOR(alcon) and Technis(AMO) multifocal iols
ReZoom lens • Flexible,3-piece , acrylic, distance dominant zonal refractive IOL • Insertion through 2.8 mm CCI • 5 expanded refractive zones within the 6 mm optic & produces 2.80 D of near power • Pupil must be 2 mm to reach the near effect
Multiple focal points of a refractive multifocal IOL
DIFFRACTIVE MULTIFOCAL IOLs • Anterior aspheric surface : basic refractive power • Multiple grooves on posterior surface : diffractive power • 41% of light : distance • 41% : near vision • Pupil independent
Multiple focal points of a diffractive multifocal IOL
Acrysof ReSTOR lens(alcon lab) • FDA approved in 2005 • 1/3 piece ,acrylic ,aspheric ,foldable ,diffractive lens that simultaneously focuses light on both near and distance targets • Central 3.6mm difrractive zone is mainly for near and outside that is for distant vision • Loss of 6%-19% light which affects contrast sensitivity esp in patients with smaller pupils • ReSTOR IOL is manufactured with +4.00 D+3.00D add at IOL plane. • Patients who received +4.00D expressed dissatisfaction with the near focal point being too close
Tecnis Multifocal IOLs (AMO) • FDA approved in 2009 • Foldable,hydrophobic,diffractive aspheric acrylic lens • The diffractive steps are on the posterior aspect on the lens and extend fully to the periphery. • Diffractive Power +4.0 diopters of near addition (+3.0 Diopters at spectacle plane)
Patient selection • Relatively easy going people who place a high value on reducing dependence on glasses or contact lenses • Good potential vision • <1.00D preexisting corneal astigmatism • Demanding patients strictly avoided Special considerations: • Counselling (most important) • Accurate Biometry • IOL master strongly recommended
Surgical technique • Same as in standard SICS with a foldable acrylic IOL • Round, centered CCC completely overlapping the lens optic • Removal of all viscoelastic from behind the lens • Optimal refractive effects depend upon good centration • Discouraged in case of inadequate centration or if posterior capsule is not intact
Side effects and complications • Capsular opacification • Glare,halos,and ghosting than a monofocal IOL or an accommodating IOL • Decreased contrast sensitivity • Intermediate vision may be weaker with multifocal IOLs than an accommodating one • Requires Visual-Cortical Neuro-adaptation
Preferances
ASPHERIC IOLs • Human eye : Aspheric Optics • Cornea : Positive spherical aberration • Young crystalline lens : Negative spherical aberration • Ageing crystalline lens : Increased positive spherical aberration • spherical aberration ~ fourth power of the pupil diameter
Anterior prolate surface • Tecnis, Advanced Medical Optics (AMO) Posterior prolate surface • Acrysof IQ, Alcon Laboratories Both Anterior and Posterior prolate surfaces • Akreos AO, SofPort AO and L161 AO, Bausch & Lomb
ASPHERIC IOLs Advantages Disadvantages
ACCOMMODATIVE IOLs • Monofocal IOL • To restore a significant amount of true accommodation to patients with surgically induced pseudophakia. • During ciliary muscle contraction,forward displacement of the IOL led to an increase in the IOLs effective power and thus an improvement in near vision. • 1 mm of anterior movement of lens = 1.80 D of accommodation • Mimicking the eye's natural ability to focus Crytalens ( Baush & Lomb):modified silicone, plate haptic(hinged),biconvex optic which potentially allow anterior movement of the lens during accommodation.
Accomodative IOLs • Another theory is ciliary muscle contraction causes a steepening of anterior optic surface allowing for better near vision. • Only FDA approved IOL for correction of presbyopia
• Although the exact cause of movement is unclear,it appears to be the a combination of posterior chamber pressure on the back surface of iol and Cilliary Body pressure on the iol haptics that vaults the optic forward. • As the ciliary body contracts,increased pressure is transmitted via vitreous to polyamide haptics & the compression betwwen the haptics causes the optic to bow forward • Accomodative arching of the lens enhances depth of focus Hydrophilic Acrylic,single optic • BioComFold type 43E (Morcher GmbH) • 1CU (HumanOptics AG) • Tetraflex (Lenstec Inc.) Development is also currently underway for dual optics IOLs eg,Sychrony IOL(visiogen,Irvine,CA) and deformable IOLs(smart IOL)
Synchrony Dual-Optic IOL (Visiogen) • One piece Silicon foldable IOL • Two optics • high plus anterior • posterior minus lens • connected by spring like haptics. • Zonular tension is released – compression of optic-spring haptic releases anterior optic forward.
TORIC IOLs • 15-29% of patients undergoing cataract surgery have substantial corneal astigmatism >=1.50 D • Either we go for arcuate keratotomy or limbal relaxing procedures or alternatively a toric IOL can incorporate the astigmatic correction into the spherical IOL power.
INSTRUMENTATION • STAAR toric IOL • First FDA approved (in 1998) toric IOL • Single piece,plate haptic,foldable silicone IOL designed to be placed in capsular bag using an injector through a 3mm incision.once in the eye ,it must be oriented with its long axis precisely in the steep meridian. • 6mm biconvex optic with a spherocyndrical anterior and spherical posterior surface. • Spherical power in the range of =9.5 to =28.5 D with a choice of cylindrical powers of 2.00 and 3.50D which correct 1.50 and 2.25 D of astigmatism respectively
……… • AcrySof IQ Toric IOL (Alcon Labs, USA) • Recently approved by FDA • 6mm biconvex acrlic optic,available in the range of +6 to +30 D & 3 astigmatism powers :+1.50 D,+2.25D and +3.00 D which correct +1.03,+1.55&+2.06 D respectively • Posterior surface has added cylindrical power and axis markings on the lens optic
Patient selection • CANDIDATES > or = 1.0D i.e mild to moderate regular corneal astigmatism • Patients with astigmatism in amounts exceeding the upper correction limits of these lenses may require additional measures to obtain full correction • Limitations of toric iols must be explained before hand • Patients should be infrmed as the lens may rotate within capsular bag • Inappropriate for the Patient who may require silicone oil for RD repair in future
Planning and surgical technique • Amount and axis of astigmatism should be measured accurately with a keratometer or if possible coneal topography • AcrySof Toric IOL Calculator generates correct power and model lens as well as orientation of the lens alignment markers • compensates for surgically induced astigmatism
…….. • Vertical& horizontal meridians should be marked on the cornea with the pt in an upright position. • reference marks at the 3- and 9-o’clock • After the IOL is injected into the capsular bag viscoelastic material behind the IOL is aspirated and the IOL is rotated into the position on the steep meridian • It may roate when balanced saline solution is injected to reform the AC • Final alignment
Complications • Possibility of IOL rotation as full correction is not achieved unless the IOL is properly aligned in the axis of astigmatism According to STAAR,a 10 degree off axis rotation reduces the correction by approx. 1/3rd • 20degree by 2/3rd • And an off axis correction of more than 30 dregree can actually increase the cylindrical refractive error. • When a plate haptic toric IOL is used,surgeon should take care when performing Nd:Yag capsulotomy .if the capsulotomy is too large a plate haptic may prolapse posteriorly Typically a misaligned IOL is recognized within days of surgery,it should be repositioned before permanent fibrosis occurs within capsular bag.
ROLLABLE IOLs • Ultrathin ~100 µ • Hydrophilic material • Front surface curved • Back surface: series of steps with concentric rings • Open up gradually • Implanted by phakonit technique Eg: • Acrismart • Thin Optx ultrachoice • Slimflex lens
ANIRIDIA IOLS • Cover the defects of aniridia or partial iris loss as in trauma • Has a black diaphragm over the optic
Phakic IOLS
PHAKIC IOLS • Implantation of IOL without removing natural crystalline lens. • ADVANTAGE: Preserves natural accommodation • Mostly used in Myopic eyes: -5 to -20 DS • Also used in Hyperopic eyes • Concern in Hyperopes: • More chances of endothelial damage • Increased risk of angle closure glaucoma • Life-long regular follow up required.
Types • Posterior Chamber • Iris fixated • Angle fixated
Patient selection • Patients who are near or beyond the FDA approved limits for laser vision correction • Patient with extreme corneal curvatures(flatter than 34 D in myopics corrections and steeper than 50 D in hyperopic corrections after laser refractive surgeries) CONTRAINDICATIONS: Patients with compromised corneal endothelium,iritis,rubeosis iridis,cataract & glaucoma • Informed consent must be taken Ancillary tests :specular microscopy,corneal pachymetry and AC depth
SURGICAL TECHNIQUE • TA with an intracameral supplement is appropriate and PIOL is inserted through a small incision • A perpipheral iridotomy is recommended for all currently FDA approved PIOLs reduce the risk of puppilary block and angle closure. • Preoperative iridotomy is preferable when small incision implant surgery is performed bcoz surgical iridotomy or iridectomy is technically difficult to perform through beveled clear corneal incision • Viscoelastic material should be meticulously removed at the conclusion of surgery to prevent post op IOP spike.
Posterior chamber phakic lens • Implantable collamer lens (ICL) (VISIAN; STAAR) • Sticklens Correct IOL length is selected by using the white to white measurement between 3 and 9 o clock positions.
Implantable Collamer Lens (ICL) • Pre-crystalline lens made of silicone or collamer • Co-polymer of HEMA(99%)+Porcine collagen(1%) Overall size- 11-13 mm Optical zone - 4.5-5.5 mm • Optic of the PCPIOL is vaulted both to avoid contact with the crystalline lens ans to allow aqueous to flow over the crystalline lens • Currently approved for myopes with - 3.00D TO -20.00D in adults 21-45 age group with a minimum AC dephth=3 mm Avoid touching the central aprt of crystalline lens
COMPLICATIONS: • Endothelial cell damage • Inflammation • Pigment dispersal • Elevated IOP • Cataract
IRIS FIXATED PHAKIC IOL • VERISYSE/ARTISAN (AMO/OPTECH): • Myopia -5.00 to -20.00 D in patients 21 yrs or older ,min. AC depth 3.2 mm • Made of PMMA,convexo- concave,Length = 8.5 mm,Optic size = 5-6 mm • Claw Haptics fixed to iris by a encavation process • Generally inserted through a superior limbal incision with side ports are made at 10 & 2 o clock positions. • Specialised encavation needle is introduced from one of the side ports and a knucle of iris is brought up into the claw haptic
ADVANTAGES OVER ICL: • Customized smaller size possible • Easier examination from end-to-end COMPLICATIONS- • Early post op AC inflammation • Glaucoma • Iris atrophy on fixation sites • Implant dislocation • De-centration • Endothelial cell loss
ANGLE FIXATED PHAKIC IOL • TWO TYPES- -4 point fixation • Baikoffs modification of Kelman type haptic design -3 point fixation • Vivarte(IOLtech) • Can be inserted through a temporal clear corneal incision or a scleral pocket • No ACPIOL is currently FDA approved
Complications Endothelial cell loss Irregular pupil Iris depigmentation Post-op inflammation Halos and glare Surgical induced astigmatism
PIGGYBACK IOLs • An intraocular lens that “piggybacks” onto an existing intraocular lens or two IOLs are implanted simultaneously. • First IOL is placed in the capsular bag. • The second (piggyback) IOL is placed in the bag or sulcus.
• Easier to place 2nd IOL than to explant IOL & replace it • Lesser risk • More predictable • Can change power with time-by adding IOL or explanting an IOL • Better image quality • Increased depth of focus
COMPLICATIONS • Interlenticular opacification • (Interpseudophakos Elshnig’s pearls) (RED ROCK SYNDROME) • Unpredictable final IOL position
THE FUTURE IOLs LIGHT ADJUSTABLE IOL TELESCOPIC IOLs SMART IOLs
LIGHT ADJUSTABLE IOLS Calhoun Vision • 3 piece Silicone optic PCIOL with two C-PMMA haptics • Silicone matrix has been embedded with silicone subunits called macromers. • Photosensitive to the near-ultraviolet wavelength of energy in a specific pattern,when irradiated with UV light through slit lamp delivery system ,the macromere polymerise and are depleted. • Monomers from the non irradiated part of IOL optic are in higher centre bcoz of induced osmotic gradient move to the centre and cause the IOL to swell up and increases the power of IOL • myopic adjustment : periphery of the lens • Final irradiation step locks in is done & IOL optic is diffusely irradiated within 1-2 weeks post op once the desired power has been acheived • Nomograms have been developed that can reportedly correct over a 5.00D range of myopia,hyperopia,astigmatism.
• Sunglasses for about three weeks
BLUE LIGHT FILTERING IOLs • Lenses are yellow colored to screen out UV Light and blue spectrum • Reduced risk of age related macular degeneration PHOTOCHROMATIC IOLs • UV absorbing photo chromes
IMPLANTABLE MINIATURE TELESCOPE • Miniature implantable Galilean telescope • Implanted in posterior chamber • Contains number of micro lenses in the optic which gives a magnification of about 3 at the central visual field • Used to treat macular degeneration
TELESCOPIC IOLs • New generation miniature telescopes which uses 2 mirrors instead of lens to provide magnification with minimum loss of peripheral vision
BIOMETRY THEOREITICAL FORMULAE • Binkhorst formula • Colenbrander’s formula • Gull strand’s formula • Hoffer’s formula EMPERICAL FORMULAE • Modified Sanders-Retzlaff-Kraff formula • SRK II • SRK III • SRK T • Haigis formula
Modified SRK( Sanders-Retzlaff-Kraff formula) • E=A - 2.5L - 0.9K • Parameters used in the formula are estimated by • A-scan ultrasonographic sonometry and keratometry • Instrument - biometer Based on the statistical correlation between calculated and observed refractive error after ocular implantation.
E=A - 2.5L - 0.9K
• Power ( I )required to produce Required post operative refraction ( R ) , I = E – cr R • cr – empirical constant cr = 1 if E < 14 cr = 1.25 if E > 14
Smart lens(medennium,irwine,CA) • Thermoplastic acrylic gel that can be customized into any size,shape,or power specified by the physician would allow the patients to retain accommodation. • The hydrophobic acrylic material is chemically bonded to wax,which melts inside the eye at body temperature & allows the predetermined shape,powe of the material to emerge. • Theoretically,compression of this pliable lens by the capsular bag would allow adjustment of its effective power in a manner similar to the way the crystalline lens adjusts. • Other examples of deformable IOLs that are still in preliminary stage of development are:Flexoptic(AMO),Fluidvision IOL(Power vision,Belmont ,CA),NuLens(NuLens,Israel)
RECENT ADVANCES IN INTRAOCULAR LENS

More Related Content

PPT
IOL Selection- What to Ask and What to Tell Patients
bypresmedaustralia
 
PPTX
Newer IOLs
byDr. Ajay Kumar Singh
 
PDF
Intraocular lens
byVASIUR RAHMAN
 
PPTX
Mutifocal iols
bysri kiran eye institue
 
PDF
Types of IOL and Microlentics-2.pdf iol p
byraveenkumari262
 
PPTX
Multifocal IOL
byAsad Zaman
 
PPTX
Intra Oular Lenses
byslidenka
 
PPTX
Update in intraocular lenses
byÁlvaro Rodríguez-Ratón
 
IOL Selection- What to Ask and What to Tell Patients
bypresmedaustralia
 
Newer IOLs
byDr. Ajay Kumar Singh
 
Intraocular lens
byVASIUR RAHMAN
 
Mutifocal iols
bysri kiran eye institue
 
Types of IOL and Microlentics-2.pdf iol p
byraveenkumari262
 
Multifocal IOL
byAsad Zaman
 
Intra Oular Lenses
byslidenka
 
Update in intraocular lenses
byÁlvaro Rodríguez-Ratón
 

What's hot

PPT
10-subluxated-lens.ppt
byAdel930879
 
PPTX
Anophthalmic socket
bySivateja Challa
 
PPTX
Epiretinal membrane
byPushkal Katara
 
PPTX
keratoprosthesis
bySivateja Challa
 
PPTX
Macular hole
byDr Samarth Mishra
 
PPTX
Vitreous substitutes
bySSSIHMS-PG
 
PPTX
Anterior segment OCT & UBM
byDinesh Madduri
 
PPTX
Pseudoexfoliation syndrome
byGloria George
 
PPTX
Types of iol
byRohit Rao
 
PPTX
Penetrating Keratoplasty
byJigyasa Sahu
 
PPTX
Minimally invasive glaucoma surgery
byaditisingh77985
 
PPTX
Intra Ocular lens
bydipusarkar2
 
PPTX
Phakic Intraocular lens
byrumi das
 
PPTX
Implantable Collamer (Contact) Lens
byDr Mohd Najmussadiq Khan
 
PPTX
Diagnosis of pre perimetric glaucoma
bySadhwini Harish
 
PPTX
Iridodialysis repair
byArchanaShetty28
 
PPTX
The limbus
byMohmmad Dmour , MD
 
PPT
laser lenses for retinal diseases
bynalini2218
 
PPTX
Tissue Adhesive In Ophthalmology
byDiyarAlzubaidy
 
PPTX
Multifocal iols
bySSSIHMS-PG
 
10-subluxated-lens.ppt
byAdel930879
 
Anophthalmic socket
bySivateja Challa
 
Epiretinal membrane
byPushkal Katara
 
keratoprosthesis
bySivateja Challa
 
Macular hole
byDr Samarth Mishra
 
Vitreous substitutes
bySSSIHMS-PG
 
Anterior segment OCT & UBM
byDinesh Madduri
 
Pseudoexfoliation syndrome
byGloria George
 
Types of iol
byRohit Rao
 
Penetrating Keratoplasty
byJigyasa Sahu
 
Minimally invasive glaucoma surgery
byaditisingh77985
 
Intra Ocular lens
bydipusarkar2
 
Phakic Intraocular lens
byrumi das
 
Implantable Collamer (Contact) Lens
byDr Mohd Najmussadiq Khan
 
Diagnosis of pre perimetric glaucoma
bySadhwini Harish
 
Iridodialysis repair
byArchanaShetty28
 
The limbus
byMohmmad Dmour , MD
 
laser lenses for retinal diseases
bynalini2218
 
Tissue Adhesive In Ophthalmology
byDiyarAlzubaidy
 
Multifocal iols
bySSSIHMS-PG
 

Viewers also liked

PPTX
Intraocular lenses
bySumeet Agrawal
 
PPT
Cachet Secoir
byINSTITUTO DE OFTALMOLOGIA AVANZADA
 
PPTX
IOL power calculation special situations
byLaxmi Eye Institute
 
PPTX
Biometry & Iol calculations
byrakesh jaiswal
 
PPTX
Ocular viscoelastic devices(OVD)
bySivateja Challa
 
PPT
IOL Power Calculation in Normal Eyes
byAmirhossein Mirfendereski
 
PPTX
Ocular viscosurgical devices
byNikhil Rp
 
PPTX
IOL power calculation formulae
bypujarai
 
PPT
Biometry for Cataract
byDevin Prabhakar
 
PPTX
Biometry
byHossein Mirzaie
 
Intraocular lenses
bySumeet Agrawal
 
Cachet Secoir
byINSTITUTO DE OFTALMOLOGIA AVANZADA
 
IOL power calculation special situations
byLaxmi Eye Institute
 
Biometry & Iol calculations
byrakesh jaiswal
 
Ocular viscoelastic devices(OVD)
bySivateja Challa
 
IOL Power Calculation in Normal Eyes
byAmirhossein Mirfendereski
 
Ocular viscosurgical devices
byNikhil Rp
 
IOL power calculation formulae
bypujarai
 
Biometry for Cataract
byDevin Prabhakar
 
Biometry
byHossein Mirzaie
 

Similar to RECENT ADVANCES IN INTRAOCULAR LENS

PPTX
Types of IOL. Cataract instruments used it
bykanishkakathir1
 
PPTX
TYPES OF IOL in ophthalmology- recent advances
byDhvaniNaik1
 
PPTX
IOL IN CATARACT SURGERY.pptx
byDshri Sankar
 
PPT
NW2012 Intraocular Lens Design and Effects on Vision
byNawat Watanachai
 
PPTX
The Right Contact
bytherightcontact
 
PPTX
The Right Contact
bytherightcontact
 
PPTX
APHACIC IOL
byAlshymaa Moustafa
 
PPTX
Presbyopia ( Part 1 / lenticular approach )..Types of MFIOL
byDiyarAlzubaidy
 
PPTX
Let's learn everything about MULTIFOCAL IOL .pptx
byranjitaamanatya111
 
PPTX
Intra ocular lens
byVishnu Narayanan
 
ODP
Accommodative and multifocal intraocular lenses
byBijan Farpour
 
PDF
Accommodative Intraocular Lenses-Crimson Publishers
byCrimsonpublishersMedical
 
PPTX
Cataract Surgery . IOL s.pptx types of IOLs
byMamataStephen
 
PPT
Optical rehabilitation or Correction of Aphakia
byNikhil Bansal
 
PPT
Pre And Postoperative Care Of The Modern Cataract Patient
byDr. Dean Dornic
 
PPT
Advances in presbyopia treatment
byperfectvision
 
PPTX
Premium intraocular lenses The past, present and-3.pptx
byMushtaq Ahmad
 
PPTX
Intraocular lens
bySai Sandeep
 
PPTX
Evolution, types, materials of iol
byBipin Bista
 
PPTX
Phakic IOL
byGauree Gattani
 
Types of IOL. Cataract instruments used it
bykanishkakathir1
 
TYPES OF IOL in ophthalmology- recent advances
byDhvaniNaik1
 
IOL IN CATARACT SURGERY.pptx
byDshri Sankar
 
NW2012 Intraocular Lens Design and Effects on Vision
byNawat Watanachai
 
The Right Contact
bytherightcontact
 
The Right Contact
bytherightcontact
 
APHACIC IOL
byAlshymaa Moustafa
 
Presbyopia ( Part 1 / lenticular approach )..Types of MFIOL
byDiyarAlzubaidy
 
Let's learn everything about MULTIFOCAL IOL .pptx
byranjitaamanatya111
 
Intra ocular lens
byVishnu Narayanan
 
Accommodative and multifocal intraocular lenses
byBijan Farpour
 
Accommodative Intraocular Lenses-Crimson Publishers
byCrimsonpublishersMedical
 
Cataract Surgery . IOL s.pptx types of IOLs
byMamataStephen
 
Optical rehabilitation or Correction of Aphakia
byNikhil Bansal
 
Pre And Postoperative Care Of The Modern Cataract Patient
byDr. Dean Dornic
 
Advances in presbyopia treatment
byperfectvision
 
Premium intraocular lenses The past, present and-3.pptx
byMushtaq Ahmad
 
Intraocular lens
bySai Sandeep
 
Evolution, types, materials of iol
byBipin Bista
 
Phakic IOL
byGauree Gattani
 

More from Dr Laltanpuia Chhangte

PDF
A case of odontogenic orbital cellulitis causing blindness in young male
byDr Laltanpuia Chhangte
 
PDF
Epidemiological and microbiological profile of infectious corneal ulcers in t...
byDr Laltanpuia Chhangte
 
PPTX
Complications of cataract surgery
byDr Laltanpuia Chhangte
 
PPTX
Anterior uveitis
byDr Laltanpuia Chhangte
 
PPTX
Sensory evaluation of squint
byDr Laltanpuia Chhangte
 
PPTX
Optic nerve head evaluation in glaucoma
byDr Laltanpuia Chhangte
 
A case of odontogenic orbital cellulitis causing blindness in young male
byDr Laltanpuia Chhangte
 
Epidemiological and microbiological profile of infectious corneal ulcers in t...
byDr Laltanpuia Chhangte
 
Complications of cataract surgery
byDr Laltanpuia Chhangte
 
Anterior uveitis
byDr Laltanpuia Chhangte
 
Sensory evaluation of squint
byDr Laltanpuia Chhangte
 
Optic nerve head evaluation in glaucoma
byDr Laltanpuia Chhangte
 

Recently uploaded

PPTX
BRONCHIAL ASTHMA.pptx by gokulakrishnan
byGOKULAKRISHNAN JANARTHANAN
 
PPTX
EQUIPMENT USED IN HEMATOLOGY LABORATORY.pptx
byKISMAT ALI
 
PPTX
DNS deviated nasal septum ent ward s.pptx
bysyedahiba121
 
PPTX
WHEN NOT TO DO TENDOACHILLES TENOTOMY.pptx
byUmeshPrasadChoudhary
 
PPTX
cardiac transplantation vp copy copy.pptx
byabay35110
 
PDF
Key Pharmaceutical Advisory Firms for Early-Stage Biotech Businesses
byk kumar
 
PDF
SEMINARIO BIOMOL.pdf (Samuel Cantillo y Karen Bohorquez)
bySamuelCantillo7
 
PPTX
Left Ventricular Assist Devices.(New Gen)
bySyedFaisalAhmed12
 
PPTX
CATARACT SURGERY... KAL AAJ AUR KAL... THE PAST, THE PRESENT AND THE FUTURE.
byirfanrawal
 
PPTX
CTEV [ clubfoot] DR ARUN LAL ,DR MOHAMED ASHRAF travancore medical college k...
bydrashraf369
 
PPTX
Formulation Development & Evaluation of Polyherbal Soap
bypurwaborkar@gmail.com
 
PDF
Dr. David Ford Wilson - Provides Holistic Mental Health Care
byDr. David Ford Wilson
 
PPTX
Acute kidney injury and its management.pptx
byrozhnuraddin
 
PPT
Rethinking Pulmonary Fibrosis: From Fine-Tuning Diagnosis to Illuminating Nov...
byPVI, PeerView Institute for Medical Education
 
PPTX
Journal club on cross trial gastric.pptx
byKishore Chandra Korada
 
PPTX
EMPHYSEMA.cardio pptx by gokulakrishnan sports
byGOKULAKRISHNAN JANARTHANAN
 
PPTX
IDENTIFICATION OF BACTERIA.by Molecular methods
byAmeenKhan59
 
PDF
The Doctor's Balance Sheet By Dr Kanhu Charan Patro
byKanhu Charan
 
PPTX
PRODUCTION OF ANTIBIOTICS e.g (Penicillin)
bySadaqat Ahmed
 
PPTX
Recent and update advances in RMNCAH+N.pptx
bypoornimatomar21
 
BRONCHIAL ASTHMA.pptx by gokulakrishnan
byGOKULAKRISHNAN JANARTHANAN
 
EQUIPMENT USED IN HEMATOLOGY LABORATORY.pptx
byKISMAT ALI
 
DNS deviated nasal septum ent ward s.pptx
bysyedahiba121
 
WHEN NOT TO DO TENDOACHILLES TENOTOMY.pptx
byUmeshPrasadChoudhary
 
cardiac transplantation vp copy copy.pptx
byabay35110
 
Key Pharmaceutical Advisory Firms for Early-Stage Biotech Businesses
byk kumar
 
SEMINARIO BIOMOL.pdf (Samuel Cantillo y Karen Bohorquez)
bySamuelCantillo7
 
Left Ventricular Assist Devices.(New Gen)
bySyedFaisalAhmed12
 
CATARACT SURGERY... KAL AAJ AUR KAL... THE PAST, THE PRESENT AND THE FUTURE.
byirfanrawal
 
CTEV [ clubfoot] DR ARUN LAL ,DR MOHAMED ASHRAF travancore medical college k...
bydrashraf369
 
Formulation Development & Evaluation of Polyherbal Soap
bypurwaborkar@gmail.com
 
Dr. David Ford Wilson - Provides Holistic Mental Health Care
byDr. David Ford Wilson
 
Acute kidney injury and its management.pptx
byrozhnuraddin
 
Rethinking Pulmonary Fibrosis: From Fine-Tuning Diagnosis to Illuminating Nov...
byPVI, PeerView Institute for Medical Education
 
Journal club on cross trial gastric.pptx
byKishore Chandra Korada
 
EMPHYSEMA.cardio pptx by gokulakrishnan sports
byGOKULAKRISHNAN JANARTHANAN
 
IDENTIFICATION OF BACTERIA.by Molecular methods
byAmeenKhan59
 
The Doctor's Balance Sheet By Dr Kanhu Charan Patro
byKanhu Charan
 
PRODUCTION OF ANTIBIOTICS e.g (Penicillin)
bySadaqat Ahmed
 
Recent and update advances in RMNCAH+N.pptx
bypoornimatomar21
 

RECENT ADVANCES IN INTRAOCULAR LENS

  • 1.
    RECENT ADVANCES INIOLS Dr. Laltanpuia Chhangte GMC ,HALDWANI
  • 2.
    What is intraocularlens? • An artificial lens implanted in the eyes • Replaces the crystalline lens • To correct the optical power of the eyes following:- Lens being clouded by cataract Refractive surgery
  • 3.
    Primary vs secondaryimplantation • Primary implantation – use of IOLs during surgery for cataract • Secondary implantation – implantation of IOL to correct aphakia in a previosly operated eye
  • 4.
    Parts of anIOL • OPTIC Part of the lens that focuses light on the retina. • HAPTIC Small filaments connected to the optic that hold the lens in place in the eye HAPTEN OPTIC
  • 5.
  • 6.
    THE FIRST IOL!! •PMMA made lens – 45 year old female after performing extracapsular cataract extraction • Disc shaped bi-convex design • Site- posterior chamber • First generation IOL
  • 7.
    EVOLUTION OF IOLs 1.First generation IOLs • Ridley lenses • Disadvantages – posterior dislocation poor surgical technique 2. Second generation IOLs • Rigid and semi-rigid anterior chamber IOLs • Advantages – reduce posterior dislocation • Disadvantage – corneal decompensation UGH syndrome
  • 8.
    3. Third generationIOLs • Iris supported lens • Advantages- less corneal decompensation • Disadvantages – iris chaffing pupillary distortion c/c inflammation cystoid macular edema
  • 9.
    4. Fourth generationIOLs • Modern anterior chamber lens • Flexible loops and multiple point fixation • Advantages – more stable, better design, less complications • Disadvantages – anterior chamber is not the physiological site for IOL
  • 10.
    5. Fifth generationIOLs • PMMA lenses • Foldable and small incision lenses
  • 11.
    MATERIALS USED FORINTRAOCULAR LENSES Optic materials 1.Non-foldable-rigid IOL • Poly-methyl methacrylate(PMMA) Water content <1% Refractive index 1.49 Usually single piece May be penetrated by aqueous humor known as ‘glistenings’ (very rare) 2.Flexible IOLs • Silicones • Hydrophobic acrylic • Hydrophilic acrylic • Hydrogel • Collamer
  • 13.
  • 14.
    INTRAOCULAR LENS DESIGN •Single piece / monobloc • Plate haptic / open loop haptics • Angulated / planar haptics • Edge design • Optic design
  • 15.
    Different types ofhaptic angulation relative to the plane of optic:- For posterior chamber lens:- • 100 anterior angulation to keep the optic part away from the pupil. For anterior chamber lens:- • Posteriorly angulated lens to vault the intraocular lens away from the pupil
  • 16.
    ANGULATED HAPTICS ALLOWFOR ADEQUATE PUPILLARY CLEARANCE AND ADHESION TO THE POSTERIOR CAPSULE
  • 17.
  • 19.
  • 21.
    Suitable position forimplanting IOL in eye • Best placed in posterior chamber in the capsular bag.
  • 22.
    ADVANTAGES OF IN-THE-BAG PLACEMENT •Proper anatomical site • Symmetrical loop placement • Intraoperative stretching or tearing of zonules is avoided • Minimal magnification (<2%); (20-30% aphakic glasses, 7-12% aphakic contact lens, ACIOL 2-5% ) • Low incidence of lens decentration and dislocation • Maximal distance from the posterior iris pigment epithelium, iris root, and ciliary processes • Reduced posterior capsular opacification
  • 23.
    POSITIONING OF IOL 1.Posterior chamber implantation • Ciliary sulcus fixation • In the bag fixation • Scleral fixation Eg:- modified C loop type IOL
  • 24.
  • 25.
    OTHER POSITIONS: • Posteriorcapsule tear • zonular dialysis
  • 26.
  • 27.
  • 28.
    2. Anterior chamber implantation •Angle supported IOLs • Iris fixated e.g Kelman multiflex type IOL
  • 29.
    3. Iris- fixatedlens • Fixed on the iris with claws,loops or sutures • Eg- Singh and Worst’s iris claw lens
  • 30.
    BASED ON OPTICALCORRECTION 1. Mono-focal intraocular lens • Lens with uni-focal power • This common IOL type has been used for several decades . • Mono-focals are set to provide best corrected vision at near, intermediate or far distances. • Most people who choose mono-focals have their IOLs set for distance vision and use reading glasses for near activities. • Some who choose mono-focals decide to have the IOL for one eye set for distance vision, and the other set for near vision, a strategy called "monovision."
  • 31.
    …….. • The brainadapts and synthesizes the information from both eyes to provide vision at intermediate distances. People who regularly use computers, PDAs or other digital devices may find this especially useful. • Individuals considering monovision may be able to try this technique with contact lenses first to see how well they can adapt to monovision. • Those who require crisp, detailed vision may decide monovision is not for them. People with appropriate vision prescriptions may find that monovision allows them see well at most distances with little or no need for eyeglasses.
  • 32.
    2.Multifocal IOLs • SingleIOL with two or more focal points • Refractive • Diffractive • Combination of both • Simultaneous vision lenses • Pseudo-accommodation
  • 33.
    Multifocal IOLs • Multifocaliols have the advantage of providing patients with functional vision at near ,far and at intermediate distances. • Patients can have a traditional monofocal iol with a refractive target of emmetropia,mild myopia,or monovision(1 eye distance,1eye near) • The Array (AMO),Santa ana CA multifocal silicone PCIOL was the first multifocal IOL to be granted fda approval in US. • Three mutifocal lenses are currently FDA approved for use after cataract extraction: • ReZoom lens(AMO),The Acrysof ResTOR(alcon) and Technis(AMO) multifocal iols
  • 34.
    ReZoom lens • Flexible,3-piece, acrylic, distance dominant zonal refractive IOL • Insertion through 2.8 mm CCI • 5 expanded refractive zones within the 6 mm optic & produces 2.80 D of near power • Pupil must be 2 mm to reach the near effect
  • 36.
    Multiple focal pointsof a refractive multifocal IOL
  • 37.
    DIFFRACTIVE MULTIFOCAL IOLs •Anterior aspheric surface : basic refractive power • Multiple grooves on posterior surface : diffractive power • 41% of light : distance • 41% : near vision • Pupil independent
  • 38.
    Multiple focal pointsof a diffractive multifocal IOL
  • 40.
    Acrysof ReSTOR lens(alconlab) • FDA approved in 2005 • 1/3 piece ,acrylic ,aspheric ,foldable ,diffractive lens that simultaneously focuses light on both near and distance targets • Central 3.6mm difrractive zone is mainly for near and outside that is for distant vision • Loss of 6%-19% light which affects contrast sensitivity esp in patients with smaller pupils • ReSTOR IOL is manufactured with +4.00 D+3.00D add at IOL plane. • Patients who received +4.00D expressed dissatisfaction with the near focal point being too close
  • 41.
    Tecnis Multifocal IOLs(AMO) • FDA approved in 2009 • Foldable,hydrophobic,diffractive aspheric acrylic lens • The diffractive steps are on the posterior aspect on the lens and extend fully to the periphery. • Diffractive Power +4.0 diopters of near addition (+3.0 Diopters at spectacle plane)
  • 44.
    Patient selection • Relativelyeasy going people who place a high value on reducing dependence on glasses or contact lenses • Good potential vision • <1.00D preexisting corneal astigmatism • Demanding patients strictly avoided Special considerations: • Counselling (most important) • Accurate Biometry • IOL master strongly recommended
  • 45.
    Surgical technique • Sameas in standard SICS with a foldable acrylic IOL • Round, centered CCC completely overlapping the lens optic • Removal of all viscoelastic from behind the lens • Optimal refractive effects depend upon good centration • Discouraged in case of inadequate centration or if posterior capsule is not intact
  • 46.
    Side effects andcomplications • Capsular opacification • Glare,halos,and ghosting than a monofocal IOL or an accommodating IOL • Decreased contrast sensitivity • Intermediate vision may be weaker with multifocal IOLs than an accommodating one • Requires Visual-Cortical Neuro-adaptation
  • 47.
  • 48.
    ASPHERIC IOLs • Humaneye : Aspheric Optics • Cornea : Positive spherical aberration • Young crystalline lens : Negative spherical aberration • Ageing crystalline lens : Increased positive spherical aberration • spherical aberration ~ fourth power of the pupil diameter
  • 53.
    Anterior prolate surface •Tecnis, Advanced Medical Optics (AMO) Posterior prolate surface • Acrysof IQ, Alcon Laboratories Both Anterior and Posterior prolate surfaces • Akreos AO, SofPort AO and L161 AO, Bausch & Lomb
  • 54.
  • 55.
    ACCOMMODATIVE IOLs • MonofocalIOL • To restore a significant amount of true accommodation to patients with surgically induced pseudophakia. • During ciliary muscle contraction,forward displacement of the IOL led to an increase in the IOLs effective power and thus an improvement in near vision. • 1 mm of anterior movement of lens = 1.80 D of accommodation • Mimicking the eye's natural ability to focus Crytalens ( Baush & Lomb):modified silicone, plate haptic(hinged),biconvex optic which potentially allow anterior movement of the lens during accommodation.
  • 56.
    Accomodative IOLs • Anothertheory is ciliary muscle contraction causes a steepening of anterior optic surface allowing for better near vision. • Only FDA approved IOL for correction of presbyopia
  • 57.
    • Although theexact cause of movement is unclear,it appears to be the a combination of posterior chamber pressure on the back surface of iol and Cilliary Body pressure on the iol haptics that vaults the optic forward. • As the ciliary body contracts,increased pressure is transmitted via vitreous to polyamide haptics & the compression betwwen the haptics causes the optic to bow forward • Accomodative arching of the lens enhances depth of focus Hydrophilic Acrylic,single optic • BioComFold type 43E (Morcher GmbH) • 1CU (HumanOptics AG) • Tetraflex (Lenstec Inc.) Development is also currently underway for dual optics IOLs eg,Sychrony IOL(visiogen,Irvine,CA) and deformable IOLs(smart IOL)
  • 59.
    Synchrony Dual-Optic IOL(Visiogen) • One piece Silicon foldable IOL • Two optics • high plus anterior • posterior minus lens • connected by spring like haptics. • Zonular tension is released – compression of optic-spring haptic releases anterior optic forward.
  • 60.
    TORIC IOLs • 15-29%of patients undergoing cataract surgery have substantial corneal astigmatism >=1.50 D • Either we go for arcuate keratotomy or limbal relaxing procedures or alternatively a toric IOL can incorporate the astigmatic correction into the spherical IOL power.
  • 61.
    INSTRUMENTATION • STAAR toricIOL • First FDA approved (in 1998) toric IOL • Single piece,plate haptic,foldable silicone IOL designed to be placed in capsular bag using an injector through a 3mm incision.once in the eye ,it must be oriented with its long axis precisely in the steep meridian. • 6mm biconvex optic with a spherocyndrical anterior and spherical posterior surface. • Spherical power in the range of =9.5 to =28.5 D with a choice of cylindrical powers of 2.00 and 3.50D which correct 1.50 and 2.25 D of astigmatism respectively
  • 62.
    ……… • AcrySof IQToric IOL (Alcon Labs, USA) • Recently approved by FDA • 6mm biconvex acrlic optic,available in the range of +6 to +30 D & 3 astigmatism powers :+1.50 D,+2.25D and +3.00 D which correct +1.03,+1.55&+2.06 D respectively • Posterior surface has added cylindrical power and axis markings on the lens optic
  • 63.
    Patient selection • CANDIDATES> or = 1.0D i.e mild to moderate regular corneal astigmatism • Patients with astigmatism in amounts exceeding the upper correction limits of these lenses may require additional measures to obtain full correction • Limitations of toric iols must be explained before hand • Patients should be infrmed as the lens may rotate within capsular bag • Inappropriate for the Patient who may require silicone oil for RD repair in future
  • 64.
    Planning and surgicaltechnique • Amount and axis of astigmatism should be measured accurately with a keratometer or if possible coneal topography • AcrySof Toric IOL Calculator generates correct power and model lens as well as orientation of the lens alignment markers • compensates for surgically induced astigmatism
  • 65.
    …….. • Vertical& horizontalmeridians should be marked on the cornea with the pt in an upright position. • reference marks at the 3- and 9-o’clock • After the IOL is injected into the capsular bag viscoelastic material behind the IOL is aspirated and the IOL is rotated into the position on the steep meridian • It may roate when balanced saline solution is injected to reform the AC • Final alignment
  • 67.
    Complications • Possibility ofIOL rotation as full correction is not achieved unless the IOL is properly aligned in the axis of astigmatism According to STAAR,a 10 degree off axis rotation reduces the correction by approx. 1/3rd • 20degree by 2/3rd • And an off axis correction of more than 30 dregree can actually increase the cylindrical refractive error. • When a plate haptic toric IOL is used,surgeon should take care when performing Nd:Yag capsulotomy .if the capsulotomy is too large a plate haptic may prolapse posteriorly Typically a misaligned IOL is recognized within days of surgery,it should be repositioned before permanent fibrosis occurs within capsular bag.
  • 68.
    ROLLABLE IOLs • Ultrathin~100 µ • Hydrophilic material • Front surface curved • Back surface: series of steps with concentric rings • Open up gradually • Implanted by phakonit technique Eg: • Acrismart • Thin Optx ultrachoice • Slimflex lens
  • 70.
    ANIRIDIA IOLS • Coverthe defects of aniridia or partial iris loss as in trauma • Has a black diaphragm over the optic
  • 71.
  • 72.
    PHAKIC IOLS • Implantationof IOL without removing natural crystalline lens. • ADVANTAGE: Preserves natural accommodation • Mostly used in Myopic eyes: -5 to -20 DS • Also used in Hyperopic eyes • Concern in Hyperopes: • More chances of endothelial damage • Increased risk of angle closure glaucoma • Life-long regular follow up required.
  • 73.
    Types • Posterior Chamber •Iris fixated • Angle fixated
  • 74.
    Patient selection • Patientswho are near or beyond the FDA approved limits for laser vision correction • Patient with extreme corneal curvatures(flatter than 34 D in myopics corrections and steeper than 50 D in hyperopic corrections after laser refractive surgeries) CONTRAINDICATIONS: Patients with compromised corneal endothelium,iritis,rubeosis iridis,cataract & glaucoma • Informed consent must be taken Ancillary tests :specular microscopy,corneal pachymetry and AC depth
  • 75.
    SURGICAL TECHNIQUE • TAwith an intracameral supplement is appropriate and PIOL is inserted through a small incision • A perpipheral iridotomy is recommended for all currently FDA approved PIOLs reduce the risk of puppilary block and angle closure. • Preoperative iridotomy is preferable when small incision implant surgery is performed bcoz surgical iridotomy or iridectomy is technically difficult to perform through beveled clear corneal incision • Viscoelastic material should be meticulously removed at the conclusion of surgery to prevent post op IOP spike.
  • 76.
    Posterior chamber phakiclens • Implantable collamer lens (ICL) (VISIAN; STAAR) • Sticklens Correct IOL length is selected by using the white to white measurement between 3 and 9 o clock positions.
  • 77.
    Implantable Collamer Lens(ICL) • Pre-crystalline lens made of silicone or collamer • Co-polymer of HEMA(99%)+Porcine collagen(1%) Overall size- 11-13 mm Optical zone - 4.5-5.5 mm • Optic of the PCPIOL is vaulted both to avoid contact with the crystalline lens ans to allow aqueous to flow over the crystalline lens • Currently approved for myopes with - 3.00D TO -20.00D in adults 21-45 age group with a minimum AC dephth=3 mm Avoid touching the central aprt of crystalline lens
  • 78.
    COMPLICATIONS: • Endothelial celldamage • Inflammation • Pigment dispersal • Elevated IOP • Cataract
  • 79.
    IRIS FIXATED PHAKICIOL • VERISYSE/ARTISAN (AMO/OPTECH): • Myopia -5.00 to -20.00 D in patients 21 yrs or older ,min. AC depth 3.2 mm • Made of PMMA,convexo- concave,Length = 8.5 mm,Optic size = 5-6 mm • Claw Haptics fixed to iris by a encavation process • Generally inserted through a superior limbal incision with side ports are made at 10 & 2 o clock positions. • Specialised encavation needle is introduced from one of the side ports and a knucle of iris is brought up into the claw haptic
  • 80.
    ADVANTAGES OVER ICL: •Customized smaller size possible • Easier examination from end-to-end COMPLICATIONS- • Early post op AC inflammation • Glaucoma • Iris atrophy on fixation sites • Implant dislocation • De-centration • Endothelial cell loss
  • 81.
    ANGLE FIXATED PHAKICIOL • TWO TYPES- -4 point fixation • Baikoffs modification of Kelman type haptic design -3 point fixation • Vivarte(IOLtech) • Can be inserted through a temporal clear corneal incision or a scleral pocket • No ACPIOL is currently FDA approved
  • 82.
    Complications Endothelial cell loss Irregularpupil Iris depigmentation Post-op inflammation Halos and glare Surgical induced astigmatism
  • 83.
    PIGGYBACK IOLs • Anintraocular lens that “piggybacks” onto an existing intraocular lens or two IOLs are implanted simultaneously. • First IOL is placed in the capsular bag. • The second (piggyback) IOL is placed in the bag or sulcus.
  • 84.
    • Easier toplace 2nd IOL than to explant IOL & replace it • Lesser risk • More predictable • Can change power with time-by adding IOL or explanting an IOL • Better image quality • Increased depth of focus
  • 85.
    COMPLICATIONS • Interlenticular opacification •(Interpseudophakos Elshnig’s pearls) (RED ROCK SYNDROME) • Unpredictable final IOL position
  • 86.
    THE FUTURE IOLs LIGHTADJUSTABLE IOL TELESCOPIC IOLs SMART IOLs
  • 87.
    LIGHT ADJUSTABLE IOLS CalhounVision • 3 piece Silicone optic PCIOL with two C-PMMA haptics • Silicone matrix has been embedded with silicone subunits called macromers. • Photosensitive to the near-ultraviolet wavelength of energy in a specific pattern,when irradiated with UV light through slit lamp delivery system ,the macromere polymerise and are depleted. • Monomers from the non irradiated part of IOL optic are in higher centre bcoz of induced osmotic gradient move to the centre and cause the IOL to swell up and increases the power of IOL • myopic adjustment : periphery of the lens • Final irradiation step locks in is done & IOL optic is diffusely irradiated within 1-2 weeks post op once the desired power has been acheived • Nomograms have been developed that can reportedly correct over a 5.00D range of myopia,hyperopia,astigmatism.
  • 88.
    • Sunglasses forabout three weeks
  • 89.
    BLUE LIGHT FILTERINGIOLs • Lenses are yellow colored to screen out UV Light and blue spectrum • Reduced risk of age related macular degeneration PHOTOCHROMATIC IOLs • UV absorbing photo chromes
  • 90.
    IMPLANTABLE MINIATURE TELESCOPE • Miniatureimplantable Galilean telescope • Implanted in posterior chamber • Contains number of micro lenses in the optic which gives a magnification of about 3 at the central visual field • Used to treat macular degeneration
  • 91.
    TELESCOPIC IOLs • Newgeneration miniature telescopes which uses 2 mirrors instead of lens to provide magnification with minimum loss of peripheral vision
  • 92.
    BIOMETRY THEOREITICAL FORMULAE • Binkhorstformula • Colenbrander’s formula • Gull strand’s formula • Hoffer’s formula EMPERICAL FORMULAE • Modified Sanders-Retzlaff-Kraff formula • SRK II • SRK III • SRK T • Haigis formula
  • 93.
    Modified SRK( Sanders-Retzlaff-Kraff formula) •E=A - 2.5L - 0.9K • Parameters used in the formula are estimated by • A-scan ultrasonographic sonometry and keratometry • Instrument - biometer Based on the statistical correlation between calculated and observed refractive error after ocular implantation.
  • 94.
    E=A - 2.5L- 0.9K
  • 95.
    • Power (I )required to produce Required post operative refraction ( R ) , I = E – cr R • cr – empirical constant cr = 1 if E < 14 cr = 1.25 if E > 14
  • 96.
    Smart lens(medennium,irwine,CA) • Thermoplasticacrylic gel that can be customized into any size,shape,or power specified by the physician would allow the patients to retain accommodation. • The hydrophobic acrylic material is chemically bonded to wax,which melts inside the eye at body temperature & allows the predetermined shape,powe of the material to emerge. • Theoretically,compression of this pliable lens by the capsular bag would allow adjustment of its effective power in a manner similar to the way the crystalline lens adjusts. • Other examples of deformable IOLs that are still in preliminary stage of development are:Flexoptic(AMO),Fluidvision IOL(Power vision,Belmont ,CA),NuLens(NuLens,Israel)

Editor's Notes

  • #3 In conditions
  • #33  BASED ON EITHER REFRACTIVE OR DIFFRACTIVE OPTICS
  • #36 Zone 1,3 and 5 : distance 60% distance, 40% near and intermediate Zone 2 and 4 : near
  • #41 Depending upon pupil size,
  • #44 Apodization literally means "removing the foot“ To remove or smooth a discontinuity at the edges
  • #45 Better to avoid demanding patients
  • #46 Use is discouraged..and a monofocal lens should be placed instead
  • #47 Cap opacification is of greater concern as minimal changes in the capsule may lead to early deterioration of vision Complaints of halos tend to subside over months due to patients neural adaptation.
  • #54 Lengh is more at poles than equatorial axis ..improves image quality and visual performance
  • #56 Its an attempt to restore That’s y ACIOLS have lower A constant than PCIOL. However few studies have questioned the amplitude of true accommodation being d sole reason as ,,pupil zsize,with the rule astigmatism & mild myopid may also contribute to near vision
  • #57 Plate hinged haptics
  • #61 Either v go for arcuate keratotomy or limbal relaxing procedures during or after cat surgery.ie lasik,
  • #62 Iols are available with spherical power in the range
  • #64 Like implantation of toric iol will not eliminate the need for reading glasses And may require anither surgery to reposition it As staar is a silicone iol..while acrysof would still b an option
  • #66 As any misalignment resulting from the torsional globe rotation that sometimes may occur wih movement in supine position
  • #77 Alternative methods beng high f USG/anterior segment OCT ,slit beam or laser inferometry
  • #78 Vaulting can be confir biomicroscopymed at the slit lamp as well as with USG..
  • #88 In Mypoia instead of periphery ,central part is irradiated bczo of reduction in central thickness of iol
  • #92 No loss of peripheral vision