520 likes | 686 Views
“New Options in Anterior Surgery ”. Steven B. Siepser, MD January 12, 2009. OUTLINE. DSALK for keratoconus DSAEK for Fuch’s dystrophy ECP for glaucoma Trabectome ICL for high myopia CK for Presbyopia Crystalens No Glasses Cataract . Keratoconus overview.
E N D
“New Options in Anterior Surgery” Steven B. Siepser, MD January 12, 2009
OUTLINE • DSALK for keratoconus • DSAEK for Fuch’s dystrophy • ECP for glaucoma • Trabectome • ICL for high myopia • CK for Presbyopia • Crystalens No Glasses Cataract
Keratoconus overview • Bulging of the central cornea • First appears in teens-20’s; both eyes • Progressive loss of vision • Severe irregular astigmatism • Management: glasses RGP contacts corneal transplant
Keratoconus Analogy BROOKLYN BRIDGE RINGLETS
Munson’s Sign Apical Scarring
Penetrating Keratoplasty • Transplant procedure • Removal of full thickness corneal button • Donor cornea and recipient • Transfer to a recipient eye PKP
Disadvantages of PKP • “Open Sky” • Eye is open during the surgery • Expulsive hemorrhage • Contents of eye are forced out by hemorrhage • Increased infection rate • Long recuperation period • Astigmatism and suture adjustment needed • Graft failure and rejection (5 %)
Deep Stromal Automated Lamellar Keratoplasty (DSALK) AKA “Superficial Lamellar Keratoplasty” Corneal overlay
Old Management • Hold off surgery • Significant loss of best corrected vision • Severe corneal scarring or thinning • Imminent Descemetocele • Contact Lens intolerance • Progressive change
New Management • <20/30 best corrected vision • Need for optimal visual acuity • Difficult contact lens fitting • Variable visual acuity Early intervention is best…
Advantages of Earlier Surgery • Thicker cornea • Faster rehabilitation • No new astigmatism • Can have LASIK / PRK later on • Less chance of perforation
DSALK FOR KERATOCONUS KERATOCONUS DSALK AUTOMATED KERATOME
Fuch’s Dystrophy • Malfunction of corneal endothelium • Dehydration system to maintain a clear cornea • Usually females, 50’s, both eyes • Guttatae • corneal swelling, folds • Decreased vision, foreign body sensation, pain in morning • Management: “salt” drops bandage contact lens surgery
Fuch’s Dystrophy GUTTATA
Descemet’s Stripping Automated Endothelial Keratoplasty (DSAEK) AKA “Endothelial Resurfacing” or Posterior Lamellar Keratoplasty
DSAEK Surgical Procedure • Prepare endothelial graft from donor cornea • Strip and peel off Descemet’s membrane of the patient • Introduce graft into eye • Flatten, place air bubble to allow adherence to back surface of cornea • Patient should stay on back until next day
Advantages over Full-thickness Corneal Transplant • Faster healing • No stitches, therefore more predictable • Safer – small incision like cataract surgery • Vision clears more quickly • 1-3 months vs 1-2 years for standard PKP • 90% of patient’s own cornea is left
SUMMARY OF NEW TRANSPLANT PROCEDURES • Full thickness PKP is on it’s way out… • Newer transplant procedures • transplanting the diseased portion of the cornea • DSALK: anterior cornea, i.e.keratoconus • DSAEK: endothelium, i.e. Fuch’s • Both use a microkeratome (“automated”)
Glaucoma summary • Fluid inside the eye is produced by a structure called the ciliary body • Fluid is drained by the trabecular meshwork • Pressure inside the eye is too high • Damage occurs to the optic nerve • Causes a slow loss of side vision
Treating Glaucoma • DROPS • slow down the production of fluid • increase the drainage of fluid • LASER • SLT: Improves Outflow • ECP: Decreases production of acqueous • SURGERY • Trabeculectomy: Older opening method • Trabectome: Directly addresses outflow
Endoscopic Cyclophotocoagulation (ECP) • Ciliary body is cauterized with a laser to decrease production of fluid • Camera inside the eye • Instrument used: • Camera + light source + laser • Tiny optical fibres view, illuminate and treat the ciliary body • Usually ~60 laser applications
ECP • Often performed at the time of cataract extraction • Can be performed after ALT, SLT or filtering bleb surgery • A majority of patients have their pressure reduced, leading many to eliminate drops
Myopic Refractive Surgery • Total US Population = 301,362,263 • Myopic 75,340,000 25% • Mild (<-2.00 D) 48,217,600 64% • Moderate (-2.00 to -6.00 D) 24,108,800 32% • High (>-6.00 D) 3,013,600 4% • Surgeons are becoming progressively less willing to attempt LASIK in high myopes (12 D) (U.S. Bureau of Census, International Database/Archives of Ophthalmology)
LASIK / PRK FOR HIGH MYOPIA • Central corneal thickness < 500 um is considered thin • Calculations can be performed to determine residual corneal thickness after treatment • Convention is to leave >300 um “untouched” • Many patients have been “turned away”
Implantable Collamer Lens (ICL) FDA Approval December 22, 2005 Dr. Siepser’s first case July 14, 2006
ICL Design • Sits behind the patients iris (colored part) • YAG PI done one week in advance • Iridectomy in the iris • Foldable • Injected through a 3mm corneal incision
ICL is Very Thin < 100 um < 50 microns 500-600 um
Indications For Use • STAAR Visian ICL is indicated for placement in the posterior chamber of the phakic eye for: • Correction of myopia -3.00 D to -15.00 D • Reduction of myopia -15.00 D to -20.00 D • < 2.50 D of astigmatism (toric ICL under FDA review)
Immediate Post-Op • High “WOW factor” • Not uncommon to see 20/40 or better vision at the early postop check • A 2-4 hour postop check is required to check pressure
Accommodation – The Missing Element • Cataract & refractive surgery focused on ‘Perfect’ distance vision without glasses, However….. Unable to effectively deal with loss of accommodation • Patients still dependent on glasses • Cataract patients want to see the same as the “young” LASIK patient and do not understand their limitation! • Presbyopes – Once again are told they need to continue to wear glasses in order to see up-close (the same story 20 years later!)
Refractive Distribution for Patients over 40 years 40.8% source: 1997 Baltimore Eye Study
CK for Presbyopia • First time reading needs • Freedom from reading glasses
Conductive Keratoplasty® (CK®) • Controlled radiofrequency • Stroma heats Tip = 7-O suture or human hair
The IOL Portfolio IOL’s come in many sizes, shapes & materials. Each has unique characteristics & capabilities Single Power Lenses Multifocal/Defractive Lenses Accommodating Lens • Single focal point • Full range of distance, intermediate & near vision • Uses eye’s natural focusing mechanism • Rapid visual recovery • Corrects only distance vision • Does not accommodate in eye • Glasses required • Multiple, fixed focal points • Does not accommodate in eye • Must find appropriate focal point • Extensive neurological • adaptation