Let me begin by saying I've been using blade-based mechanical microkeratomes for 16 years (began with ALK, the precursor of LASIK), and the Intralase for over 5 years. I've done tens of thousands of cases using each.
For some patients, the Intralase is hands-down much better (safer). This would include patients with very steeply curved corneas (blades tend to cut thin flaps here), very flat corneas (blades tend to cut thicker, smaller diameter flaps with a risk of a free cap), and thin corneas (Intralase is more precise and better able to accurately deliver a thin flap). I also prefer Intralase for very nervous patients, as well as patients with severe dry eye, or at particular risk for dry eye. In my experience, Intralase seems to have a lower incidence of dry eye postop than the keratome blade does.
For many patients with normal corneal curvature and thickness, the difference in safety between the blade and the Intralase is nominal. Both work well, though there may be a slight safety advantage with the Intralase. I quote patients a risk of flap complication of 1 in 1,000 with a blade, and 1 in 10,000 with Intralase.
