Ophthalmology Department,Tanta University, Egypt

Transcription

1 Moataz M. Sabry, MD, PhD. Ophthalmology Department,Tanta University, Egypt 1

2 SHOULD WE ABONDONE MECHANICAL MICROKERATOMES? 2

3 With Mechanical, LASIK is a one-laser procedure, there s no moving of patient or furniture to get from one laser to the next. Mechanical can be used with all types of Excimer Laser Systems. (NOT with Femtosecond Lasers) 3

4 Mechanical are faster. More comfortable to the patient. Less drying of the eye, which can affect the accuracy of the laser procedure. Less Suction Time with Mechanical (10-15 seconds) compared to one minute or more with Femtosecond Lasers. Less Incidence of suction loss compared dto femtosecond lasers. 4

5 With Mechanical, there is no need to do manual dissection of the flap which carries a risk of flap tears and disrupts the stromal surface. Renee Solomon (M.D., Long Island, N.Y.), compared the flap creations of femtosecond laser vs. mechanical microkeratome. The stromal beds of the mechanical microkeratome and the femtosecond keratome were compared. 5

6 MECHANICAL FEMTOSECOND Stromal bed has mild areas of surface irregularity with significant smooth areas. Individual keratocytes can be visualized. Stromal bed appears to have course spongelike appearance with multiple crevices and irregularities. OUP-SBK Intralase 60 khz Scanning EM x20 After cutting a flap with an intended flap thickness of 100 microns 6

7 Femtosecond Lasers can create thin planner flaps for Sub-Bowman Keratomileusis however Mechanical can create thin flaps with the use of different heads and with the One Use Plus-SBK from Moria we can get thin and planner flaps comparable to those obtained by femtosecond lasers. 7

8 5/31/2010 Osama Ibrahim, MD, ESCRS winter 2009 Courtesy of James S. Lewis, MD. Elkins Park, PA, USA Osama Ibrahim, MD, ESCRS winter

9 Osama Ibrahim, MD, ESCRS winter 2009 Osama Ibrahim, MD, ESCRS winter

10 Mechanical can mechanically create an epithelial flap (Epi-LASIK) for surface ablation. Mechanical offer a rapid visual recovery post-operative compared to Femtosecond Lasers that lacks the (wow factor) of early visual recovery*. *Donnenfeld ED. FS laser: Not ready for prime time. Ophthalmology Management. 200;8(suppl): Woodhams TJ. Does a better flap improve outcomes? Ophthalmology Management.2004;(suppl):

11 Osama Ibrahim, MD Pre ESCRS 2008 meeting, Berlin Osama Ibrahim, MD Pre ESCRS 2008 meeting, Berlin 11

12 There are no statistically i significant ifi difference in postoperative vision or higher order aberrations found in direct comparison of Mechanical with Femtosecond Lasers*. *Kezirian GM, Stonecipher KG. Comparison of the IntraLase femtosecond laser and mechanical keratomes for laser in situ keratomileusis. J Cataract Refract Surg. 2004;30: Percent of Patients 1 Hansatome Intralase 99% 98% % 67% /20 or better 20/40 or better *Kezirian GM, Stonecipher KG. Comparison of the IntraLase femtosecond laser and mechanical keratomes for laser in situ keratomileusis. J Cataract Refract Surg. 2004;30:

13 Patients may experience slightly more postoperative discomfort with IntraLASIK than with mechanical LASIK, Because the FS laser s flap is created by the removal of tissue within the stroma and around its circumference thus the flap is smaller than the stromal bed*. *Donnenfeld ED. FS laser: Not ready for prime time. Ophthalmology Management. 200;8(suppl): Goldberg DB. The IntraLASIK learning curve. Cataract & Refractive Surgery Today. 2004;4: Osama Ibrahim, MD Pre ESCRS 2008 meeting, Berlin 13

14 Osama Ibrahim, MD Pre ESCRS 2008 meeting, Berlin Mechanical Femtosecond 14

15 The difference in size between the flap and the stromal bed with femtosecond lasers can result in the occurrence of post-operative flap folds that need (reseating) and may resist treatment by flap repositioning*. *Biser SA, Bloom AH, Donnenfeld ED. Flap folds after femtosecond LASIK. Eye Contact Lens. 2003;29:

16 Flap lift for retreatment is much easier for flaps created with Mechanical than those created with Femtosecond Lasers due to tight adhesions between the flap and the bed specially at the flap edge. 16

17 Although the incidence of complications is lower with Femtosecond Lasers compared to Mechanical, we should keep in mind that Intra-LASIK is a safe but not a risk-free procedure. Percent of Patients Suction Loss 0.09 Button Hole Irregular Cut Bubble in AC Incomplete Cut Thin Flap Flap Tear Epithelial Defect Intralase Flap Complications *Menthyie Onder, MD. Complications and management of IntraLasik. Presented at Instituto di recovero e cura carettere scientifico

18 Moria One Use-Plus SBK compared to Femtosecond lasers in this flap LASIK (SBK). Roundtable discussion

19 Mechanical have less incidence of post-operative flap interface inflammation (DLK) compared to Femtosecond Lasers. Although changing the laser parameters may be sufficient to address this problem specially with the new generations. 19

20 Percent of Patients DLK Mechanical Intralase *Menthyie Onder, MD. Complications and management of IntraLasik. Presented at Instituto di recovero e cura carettere scientifico A unique postoperative complication i for Femtosecond Lasers that has not been faced with Mechanical is Track Related Irido-Cyclitis and Scleritis 20

21 This syndrome consists of debilitating photophobia with good vision and no clinical signs. The syndrome is the result of inflammatory cytokines being produced in a track created by the FS laser between the LASIK flap interface and the sclera that allows the cytokines to pass to the perilimbal sclera and iris base*. *Will BR. Track-related iridocyclitis and scleritis associated with use of the IntraLase for LASIK. Paper presented at: The ASCRS/ASOA Symposium on Cataract, IOL, and Refractive Surgery; May4, 2004; San Diego, CA. Obvious Bubble Layer (OBL) is another unique finding with Femtosecond Laser which is not seen with Mechanical and sometimes there is bursting of air bubbles into AC resulting in difficult tracking and iris i registration ti failure during excimer laser ablation. 21

22 Mechanical One Laser Procedure. Used with any Laser. Faster. Less Drying. Less suction time. No Manual Dissection of flap. Mechanical Create thin flap and epithelial flap. Safer with superficial opacities. Safer with previous RK. Rapid visual recovery. Less incidence of DLK. Easier flap lift for retreatment. 22

23 The cost of initial iti acquisition iti and annual service of Femtosecond Laser is almost 6 folds that of a Mechanical Microkeratome. The Disposable single use cost of Femtosecond laser for flap creation is almost two and half folds that of a Mechanical Microkeratome. Femto-LASIK Center 23

24 Moria One Use-Plus SBK compared to Femtosecond lasers in this flap LASIK (SBK). Roundtable discussion 2009 Thank You 24

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