Transcript PHAKIC
PHAKIC IOL’S ( pIOL’S ) IN CORRECTING HIGH MYOPIA
By: H.R. ZIAI MD.
Esfand 1391 Isfahan
HISTORY
•
1950s
: First ideas formed •
1988
Bikoff : Angle supported PMMA, ZB5M & MA20, by •
But
: • Discontinued because of complications ( corneal edema, iritis ,… )
HISTORY
• •
1988
: First phakic iris – clawed IOL introduced for myopia by Worst • •
1998
: Artisan – Worst by OPHTEC • Verysise Then changed it’s name to Artisan – and it’s flexible form to Artiflex
HISTORY
•
1987:
First PC pIOL or sulcus support pIOLs introduced : • • - Phakic Refractive Lens ( PRL ) by CIBA VISON .
And then
: • • - Implantable Contact Lens ( ICL ) or Implantable Collamer Lens ( ICL ) • • - Collamer is a copolymer of hema ( 99% ) and porcine collagen ( 1% )
CLASSIFICATION OF pIOLS
• • •
Ant.Chamber pIOLS ( AC pIOLS) -
Angle supported
1) PMMA 2) Foldable
• • • • Clawed
1)PMMA 1)Foldable
Post.Chamber pIOLS ( PC pIOLS )
(or sulcus supported ) - Iris – \\\
INDICATIONS
•
High Myopia
• - Myopia > -8.00 to -10.00 D • • - Stromal bed < 300µ after laser ablation • - Keratometry < 34-36D after laser ablation
•
FDA Approval for Artisan/Artiflex
• - Myopia : -5.00 to -20.00 D • - Ast. < 2.5 D • - Age > 21 y • - ACD > 3.2 mm
•
FDA Approval for ICL :
• - Myopia : -3.00 to -20.00 D • - Ast.< 2.50 D • - Age 21 - 45 y • - ACD > 3.00 mm
•
High Hyperopia
• • • • - Keratometry > 50 D after laser ablation • - Available pIOLS : ICL : Up to +20.0 D Artisan : Up to +12.00
High Ast.
• - Laser ablation is the Tx of choice for Ast. up to 4.00 – 5.00 .
• - PIOLS are available too .
CONTRAINDICATIONS
• • - Any intraocular pathology ( Cat. , Glaucoma , NVI , Uveitis , … ) • - ↓ ACD • - ↓ Diameter
ADVANTAGS OF pIOLS
• - Rang of correction >> Laser • - Easy technique ( Like Cat. Surgery ) • - Less expensive instruments than Laser • - Removable • • • - No ↓ in contrast sensitivity even : ↑ Compared with spectacle -More predictable
DISADVANTAGES OF pIOLS
• - All intraocular risks • - Large incision ( in PMMA types ) • - Limitation in hyperopia due to small ant. segment • - Irreversible complication
PRE-OP EVALUATION
• - Power of IOL • - Diameter of IOL for angle or sulcus supported IOLs • - ACD • - Specular microscopy • - Optic size in correlation to scotoptic pupil size • - All other rutin evaluation before cat. surgery
Cont.
•
But :
• •
Main challenge in angle or sulcus supported pIOLs is
:
“ Sizing IOL diameter”
• Through Angle-to-angle • And ciliary sulcus diameter
Cont.
•
For angle supported pIOLS
• - 0.5 – 1.00 mm add to w-to-w measured manually or by orbscan, although not always correct .
• - Use of OCT/UBM
Cont .
•
Note:
• If diameter measured horizontally the lens must implanted horizontally; if implanted vertically, it causes Decenteration , Ovalization , Iritis , Glaucoma.
Cont.
• For PC pIOLS ( sulcus supported ) • - Add 0.50 – 1.00 mm to horizontal W-W • - New ultrasound techniques like Artemis & UBM
ANGLE SUPPORTED pIOLS
•
Surgical Technique (important points)
• -Incision , 2- 6.5mm (based on type ) • - Sup. approach ( more common ) • - Retrobulbar avoided ( glob perforation ) • - IOL dialled to the best pupil-optic matching
Cont.
• - Surgical PI • - OVD irrigated meticulously • - Pilo 2 ( useful , but may decentered pupil
Complications
) • -
Haloes and Glare
: more com complication ( 20 % • more in 1th year,
but
: ↓ over time •
- Pupil ovalisation
( 7-22% ) ( if oversized ) •
- Iris retraction and atrophy
Cont.
•
Endothelial cell damage:
• -Surgical trauma Presence of IOL - 5 7% in 1th year and less in next years Too small size : ↑ damage
Cont.
• • • •
- ↑ IOP
- Transient , 2’ to OVD - Topical CS - Pupilary block • • •
- Uveitis :
4.5% - Usually transient , 2’ to iris manipulation - In over sized IOL , may chronic, causing glaucoma cat. , PAS, Iris damage , …
Cont.
• • • •
- Cataract
- Less common than PC pIOL - Caused by trauma , uveitis - Age > 40 y at time of surgery • • - AL > 30 mm •
- RD
: 3% If pIOL have additive risk for RD over the myopia??
Cont.
• • • • • •
Rare complications
- Corneal decompensation - Urretis – Zavalia synd.
- Malignant glaucoma - Endophthalmitis - Hyphema
IRIS FIXATED pIOLs
•
General information of Artisan
• - 0.5 mm vault ( 0.8 mm distance between IOL & crystalin lens) • - Diameter : 8.5 mm • - Optic : 6.5 & 6.0 mm • - Center :0.2 mm thickness
Indications ( FDA ) :
• - Myopia • - Hyperopia • - RE After PK • - Sever anisometropia in children • - Aphakia • - KCN • - Progressive high myopia in psudophakic children
Complications
• -
Glare & haloes
: 0-9% more in small optics ( 5mm ) and Large pupil ( > 5.5 mm ) • -
AC inflammation
: 0.5% • -
Pigment dispersion :
2” to poor enclavation • -
Crystalin lens rise
: like Hyeperopia ( Artiflex > Artisan ) because of step in optic haptic junction
Cont.
• •
Endothelial cell loss
- Intraoperative trauma ( main cause ) • • - more in first 6m post op.
• - ACD < 3.2 → ↑ risk • •
Glaucoma
- Usually transient - OVD , CS , pigment , inflammation
Cont.
•
Cataract
: 3% - NS • - Age > 40 at implantation time →↑risk • - AL > 30 mm →↑ risk • • • •
Other complications
- Hyphema - Intermittent myopic shift - RD
PC PIOLs ( SULCUS SUPPORTED )
•
- PRL
: Silicon , hydrophobe •
- ICL
: Hydrophyl , biocompatible , permeable
Complications
• • -
Glare & halos
8.4 % , ↓ over time • -
Flare
; 27%, Up to 2y • • • • •
-Cataract
- The major concern - 0.6 – 3 % - Traumatic contact , metabolic disturbance - Ant. sub capsular
Cont.
•
Pigment dispersion & deposition
• - Iris rubbing • - ↑ Size ( ↑ Vault ) →↑ dispersion
• • • •
Glaucoma
- 2’ to pigment dispersion - Angle closure - Pupilary block ( if fibrin formed ) • • • - ICL > PRL •
Decenteration
: The most complication - Small size IOL
, difficult problem
- Even sometime dislocation into vitreous cavity
•
Note
: • In PC pIOL
, vault
is of
critical importance
• - ↑ Vault → ↑ Pigment dispersion • - ↓ Vault → ↑ Cataract
BIOPTICS
•
Implantation of pIOL followed by Laser ablation
• - In case of extremely myopia , high Ast. , lens power not available.
• - Safe and effective
FEW SELECTED POINTS
• - PIOLs have been used successfully for post PK Ast.
• - Artisan induces HOA less than APT because of reserving prolate shape of cornea.
• - Toric pIOL + CXL successfully have been used for correcting RE in mild to moderate KCN & PMD.
Cont.
• - AC pIOLs have been used for TX of children with sever myopic anysometropia ( > -8.00 ) that resist or no cooperative for traditional amblyop therapy with encouraging results .
CONCLUSION
• • • • •
Compared with corneal laser ablation, pIOLs are excellent in :
- Predictability - Efficacy - Safety - Quality of vision
شزوپ ضرع نمض
ه مادا هب زاین تروص رد دشابیمن ریذپ ناکما اهدیلاسا همادا ن فلت هرامش اب ای و هعجارم ضیف ینامرد یشزومآ زکرم یرصب و یعمس دحاو هب افطل دیئامن لصاح سامت 392 یلخاد LECTUER 03114476010 یلااب مجح لیلدب رکشت اب