SHOULD OPTOMETRISTS (ODs) BE SELLING LASIK? It was brought to our attention that "Dr." William Brand is promoting LASIK at Vision One LASIK Center on the Groupon.com website. "Dr." Brand is an optometrist, not a medical doctor (MD) or ophthalmologist. Having an optometrist do the work of a LASIK surgeon is a popular business model in the LASIK industry, but it is not in the patient's best interest. In our opinion, optometrists are not qualified to determine a patient's candidacy for LASIK eye surgery. Many LASIK patients have suffered severe, permanent complications due to the incompetence of an optometrist. A surgeon who delegates the LASIK consultation and pre-operative exam to an optometrist, technician, or other employee is reckless and greedy, in our opinion. We feel that optometrists should stick to doing what they were trained to do -- that is, dispensing glasses and contact lenses. Glasses and contacts are, afterall, a safer alternative to risky, irreversible LASIK eye surgery. Anyone who says that LASIK is safer than contact lenses is, frankly, drinking the LASIK-industry Kool-Aid. Besides, who in their right mind would purchase a surgery on Groupon.com? LASIK is a serious surgery that carries serious risk to your eyesight. Don't be fooled by slick salesmen trolling for patients on Groupon.com. Even when the surgical outcome is considered 'perfect', a patient may still suffer chronic dry eyes, diminished night vision, or face late on-set complications and other eye problems later in life as a result of LASIK.
The latest LASIK hype is the relatively new "blade-free" LASIK which uses a laser instead of a blade to cut the flap. This technology goes by many names in advertisements, such as IntraLase, femtosecond laser, all laser, bladefree, bladeless, iLASIK, and IntraLASIK. LASIK surgeons proclaim this LASIK is safer and better than the old LASIK. But as one doctor put it, "a flap is a flap, is a flap... no matter how you slice it". With the introduction of laser-created flaps, along came a whole new set of problems, and most of the old problems (like dry eyes and poor night vision) hung around...
From the article: “When we have something new, everybody is excited, everybody is up,” Dr. Maloney said, but added that new technology just replaces old complications with new complications. In such cases, he said he’s not sure if the technology has accomplishing anything. In particular, Dr. Maloney addressed comparisons to IntraLase femtosecond laser (IntraLase Corp., Irvine, Calif.). “IntraLase complications are more typically flap tears from dissection or haze following inflammation,” he said.
J Cataract Refract Surg. 2008 May;34(5):713-4. Bowman's brave new world. Dupps WJ Jr.
Intrastromal femtosecond pulses create gas bubbles that coalesce in the intrastromal interface, sometimes resulting in a transient opaque bubble layer (OBL) that can temporarily interfere with excimer laser tracking and registration systems and photoablation.
In a recent study of 149 eyes treated with a 15 kHz IntraLase system, Kaiserman et al. found that thicker flaps and smaller flap diameters were more strongly associated with OBL development, which occurred in 56% of treated eyes, and that steeper and thicker corneas had larger areas of OBL.
The femtosecond laser’s photodisruption pattern can produce a mildly corrugated stromal bed that is visible postoperatively with retroillumination. On occasion, certain excimer lasers fail to track the pupillary margin after IntraLase in eyeswith dark irides.
The highly ordered pattern imposed by the femtosecond raster pattern may also have the optical effect of creating a diffraction grating responsible for a spectral effect known as rainbow glare. Radial patterns of colored lines are most notable when the patient is presented with a point source of white light. The incidence of rainbow glare has been reported to be as high as 36% in patients who are questioned directly but is lower in newer-generation IntraLase systems.
Transient light sensitivity may occur after IntraLaseassistedLASIK and can mimic the symptomsof uveitis without demonstrable intraocular inflammation.
In addition to this new array of complications, traditional flap complications have not been entirely eliminated by femtosecond lasers. Diffuse lamellar keratitis (DLK) was more common with early femtosecond lasers than with microkeratomes, particularly in the form of flap-edge DLK.
Partial flaps are still possible with lost suction, but with the significant advantage that the flap has not been lifted and a surgical delay or second femtosecond pass are tenable options.
Thinner flaps may provoke more epithelial cytokine release than deep-flap LASIK; lead to interface haze and flap necrosis; and carry a greater risk for gas bubble breakthrough (Seider et al., pages 859-863), inadvertent epithelial flaps (Choi et al., pages 864-867), and torn flaps.
Epithelial breakthrough during IntraLase flap creation for laser in situ keratomileusis. Seider MI, Ide T, Kymionis GD, Culbertson WW, O'Brien TP, Yoo SH. J Cataract Refract Surg. 2008 May;34(5):859-63.
We report the clinical manifestations and outcomes in 4 patients who experienced premature gas-bubble leakage during raster lamellar dissection during IntraLase femtosecond laser corneal flap creation. Three patients experienced a full-thickness epithelial breakthrough and the fourth, a flap tear. The patient who experienced the flap tear was unable to have laser in situ keratomileusis successfully.
We observed 4 (0.14%) cases of epithelial breakthrough in 2922 IntraLase LASIK January 2006. It appears that if the FS laser cannot photodisrupt corneal stroma in a small portion of the intended interface or if there is resistance within the interface from scar tissue, incomplete flaps may result. The morbidity associated with this complication seems variable and may range from minimal corneal damage to significant corneal tearing, resulting in abortion of the LASIK procedure.
Rare rainbow glare side effect still occurs with latest IntraLase laser
OSN SuperSite Breaking News 4/7/2008
From the article: Use of the latest IntraLase femtosecond laser does not diminish the occurrence of a rare side effect called rainbow glare, according to a physician who has studied the phenomenon. "Rainbow glare is caused from the perfectly regular grading pattern of the IntraLASIK pulses in the interface that sets up the constructive interference that splits white light into its component colors and into a number of different bands..."
Femtosecond-laser LASIK complications
List of complications from article: suction loss while cutting the flap, gas breakthrough, opaque bubble layer, gas bubbles in anterior chamber, diffuse lamellar keratitis, extreme light sensitivity...
From the article: Even less is known when femtosecond lasers are used for LASIK, he said... "We know that suction is lower, pressure is lower, but since the procedure is longer, we are going to flatten the cornea for a longer time than with mechanical microkeratomes, and so some damage can still be caused to the optic nerve," Dr. Belda said.
J Cataract Refract Surg. 2008 Mar;34(3):417-23.
Incidence, possible risk factors, and potential effects of an opaque bubble layer created by a femtosecond laser.
Kaiserman I, Maresky HS, Bahar I, Rootman DS.
From the private laser center and the Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ontario, Canada.
PURPOSE: To describe the incidence, characteristics, risk factors, and sequelae of an opaque bubble layer created by the IntraLase (15 Khz) femtosecond laser (IntraLase, Corp.).
SETTING: Private laser center and the Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ontario, Canada.
METHODS: This study comprised 79 consecutive patients (149 eyes) who had laser in situ keratomileusis for myopic astigmatism. The preoperative visual acuity, refraction, keratometry, pachymetry, and intraoperative data including flap size and thickness were documented. A computerized system was used to calculate the total area of the opaque bubble layer.
RESULTS: Eighty-four eyes (56.4%) developed an opaque bubble layer. The layer pattern was diffuse in 32.2% of eyes and hard in 24.2%. The diffuse opaque bubble layer covered a mean of 13.4% +/- 10% of the corneal flap and the hard opaque bubble layer, a mean of 21.6% +/- 10% (P = .0004). A significant correlation was noted between the corneal steep curvature and central corneal thickness (CCT) and the area of opaque bubble layer. Multivariate logistic regression found that flap diameter (P = .04) and CCT (P = .045) affected the occurrence and area of the opaque bubble layer (P = .04 and P = .05, respectively). Postoperative diffuse lamellar keratitis was not associated with an opaque bubble layer. Three months postoperatively, visual acuity and refraction were not affected by the bubble layer. There was an increase in trefoil aberrations in eyes with a hard opaque bubble layer (P = .01).
CONCLUSIONS: Thicker corneas and smaller flaps were associated with a more opaque bubble layer. The presence of an opaque bubble layer did not seem to have detrimental long-term sequelae, although a small harmful effect could not be ruled out.
Read more about complications of IntraLase femtosecond LASIK at LINK