Femtosecond laser assisted penetrating keratoplasty Pf. 주천기/St. 노창래/R4 김재윤

C/C Dec VA(OD) for 4yrs M/35 No known systemic dz 2006년 에어건에 의해 우안 수상후 지속된 시력감소로 내원 5년전까지는 우안 시력 0.8정도 였음. No known systemic dz Ocular trauma/op (+/-) Gls(-), Eye drops(-) 2006년 우안 수상후 지속된 시력감소로 각막이식 위해 내원

VA OD FC/30cm (n-c) OS 1.0 IOP OD 9 OS 15 mmHg at 4:30(PM) Exo No exophthalmos /(OU) EOM Straight at 1' position by H-test, no LOM /(OU) Lid No swelling, No mass /(OU) Conj. OD Mildly injected OS Not injected Cornea OD Mod edematous c microbullae, and linear, oblique, 7mm sized detachment of Descmet's memb(5 o/c-> 10 o/c), diffuse stromal opacity at central area OS Clear AC Deep & cell (-) /(OU) Pupil Round & nl sized, LR(+) /(OU) Lens Clear / (OU) B-scan(OD) : flat OD

AxL OD : 23.38 mm OS : 23.14 mm 1061μm 852μm 897μm 940 μm 943 μm

Visante OCT - Preop

Design of Graft

2010.09.20 IEK(OD) # 각막정보 사인 : Driver's TA로 인한 brain death 사시 : 2010.09.16 18:43 적출시 : 2010.09.16 20:20 담금시 : 2010.09.16 21:45 CD 2645, clear zone 10 m

2010.09.20 IEK(OD) # 각막정보 사인 : Driver's TA로 인한 brain death 사시 : 2010.09.16 18:43 적출시 : 2010.09.16 20:20 담금시 : 2010.09.16 21:45 CD 2645, clear zone 10 m

< POD #4 > VA OD 0.2 (n-c) IOP OD 10 mmHg at 7: 00 am by tonopen Cornea OD Well grafted D’s cornea, mod edematous c DM folding AC OD Deep at center, 1/2CT at pph and cell(+) Pupil OD Round & nl sized, LR(+/+) Lens OD Clear

Visante OCT – Post op

Femtosecond laser assisted Keratoplasty

Laser Spectrum INTRALASE ® FS Ultraviolet Visible Infrared Argon 457-514 nm Diode 805-820 nm Er:Yag 2940 nm Nd:Glass 1053 nm CO2 10,600 nm Excimer 193 nm 100 nm 400 nm 700 nm 100,000 nm INTRALASE ® FS Ultraviolet Visible Infrared

Principle of FS laser Femtosecond laser (Nd:Glass) 1053 nm (near infrared) Each pulse of focused laser light lasts approximately 10-15 seconds (500-800 femtoseconds) In one second, light travels 7.5 times around the globe In 100 femtoseconds, light travels across a human hair Power = Energy/Time, extremely high power attained at relatively low energy

Principle of FS laser Surgical effect is achieved through “Photodisruption” at a molecular level No thermal or shock wave transmission to surrounding tissues Laser pulses focused to precise intrastromal locations (± 5 microns) Computer controlled optical delivery system places thousands of pulses next to each other creating flaps, incisions, lamellar resections, keratectomy

Photodisruption A pulse of laser energy is focused to a precise location inside the cornea A microplasma is created, vaporizing approximately 1 micron of corneal tissue 1 Micron

Photodisruption 5 to 12 Microns An expanding bubble of gas & water is created separating the corneal lamellae

Photodisruption The bi-products of photodisruption (CO2 & water) are absorbed by the mechanism of the endothelial pump, leaving a resection plane in the cornea

Photodisruption Thousands of laser pulses are connected together in a raster pattern to define a resection plane

Photodisruption Gas & water are absorbed or liberated when corneal flap is lifted A resection plane is created

Photodisruption Laser pulses can be stacked on each other to create a vertical cleavage plane

Photodisruption Laser pulses can be stacked on each other to create an angled cleavage plane

Keratoplasty Traditional PPKP : Refractive errors, suture-related problem, torsional astigmatism d/t decenteration and wound dehiscence Mannual Top hat : transplant more endothelial cells, keeping anterior edge at a safe distance from the limbus But difficult to master, is time consuming, and may damage donor tissue. Femtosecond laser : creating full-thickness corneal trephination with customized locking edges at the graft-host junction

New approach to keratoplasty Lamellar keratoplasty Horizontal surface to surface wound Minimize the risk of an immune reaction in the graft Decreased quality of VA due to fibrosis in the wound Shaped manual keratoplasty The ability to vary the donor graft sized depending on the amount of endothelium needing to be transplanted Difficult to master Time comsuming Damage to donor tissue Earlier suture removal Stronger wound healing Shaped PPKP: stepped nature Earlier suture removal Valve sealing edge design

Femtosecond laser(Intralase®) Cornea is transparent for laser beam of Intralase (in contrast to Excimer laser) → Allows laser treatment of deep corneal layers such as endothelium or posterior stroma The IntraLase® Enabled Keratoplasty software can be programmed to produce different configurations with computer precision.

IEK (IntraLase Enabled Keratoplasty) The IntraLase Enabled Keratoplasty application allows the user to perform three cut segments: a posterior side cut, lamellar cut, and anterior side cut. Ring Lamellar Cut Posterior Side Cut Full Lamellar Cut Full Thickness Cut Anterior Side Cut

IEK (IntraLase Enabled Keratoplasty)

Example Pattern Combinations for Penetrating Keratoplasty Vertical Sidecut Tophat Tongue & Groove Mushroom ZigZag X’Mas Tree

IEK(Vertical) 538(μm) IEK(Z-squre)

580(μm) IEK(Top-hat) IEK(Mushroom) 542(μm) Mushroom-POD#5 이후에 f/u 이 잘 되지 못함 18269696 2월초에 찍었을 것 같음 다시 Visante OCT 자료 찾아보기 IEK(Mushroom) 542(μm)

Example Pattern Combinations for Lamellar Keratoplasty DALK DSEK DLEK PSC ONLY

IEK (IntraLase Enabled Keratoplasty)

TopHat Shape Provides large endothelial surface transplantation Endothelial dystrophy 등에서 유리 Fuch’s 등

Mushroom Shape Preserves more host endothelium Keratoconus등의 자기 내피는 건강한 경우 유용

ZigZag Shape Hermetic wound seal Angled edge provides smooth transition between host and donor ©1997 – 2006 IntraLase Corp. All rights reserved. Confidential – 900043 Revision A

Femtosecond Laser–assisted Penetrating Keratoplasty Stability Evaluation of Different Wound Configurations Bahar et al. ; Cornea, Vol 27(2), 2008

Femtosecond laser versus manual dissection for tophat penetrating keratoplasty Bahar et al. ; Br J Ophthalmol, Vol 93, 2009

IntraLase Enabled Keratoplasty Patient Selection Contraindications any corneal opacity adequately dense to obscure visualization of the iris descemetocoele with impending corneal rupture previous corneal incisions that might provide a potential space into which the gas produced by the procedure can escape corneal thickness requirements that are beyond the range of the system

IntraLase Enabled Keratoplasty Patient Selection Other Considerations severe corneal thinning subjects with pre-existing glaucoma a history of steroid responsive rise in intraocular pressure preoperative IOP > 21 mm Hg in the operative eye subjects with more than 1200 um corneal thickness at the 9mm peripheral zone active intraocular inflammation active ocular infection