Surgical Isolation and Fluid-tight Containment

With LAHayeSIK™, the surgical field is downsized to the patient’s cornea. The LAHayeSIK™ Handpiece establishes a more concise surgical field boundary.

Conventional LASIK - The surgical field boundaries of the conventional LASIK procedure include the patient’s lid margins, lashes, cul de sac tissues, and surgical drape (if used). (Illustration 5)

These regions may be sources of contaminations. Exposed corneal stroma (flap and flap bed) has the potential to absorb and hold fluid readily, "like a sponge". It is the opinion of most ophthalmic surgeons that reducing exposure of the cornea bed and flap tissues to the conjunctiva, cul-de sac fluids, lashes, operative drapes, and lid margins can reduce post-operative complications including infectious keratitis, and diffuse lamellar keratitis (DLK).

The flap, while in position, covers and protects the absorbent stroma. The flap and stromal bed tissues become more susceptible to contamination and other potential problems the moment the flap is reflected. Because the flap and corneal bed are exposed the entire duration of Stage II it is critical that the integrity, sterility, and "cleanliness" of the corneal incision and the corneal flap tissue be preserved throughout this multitasked aspect of the LASIK procedure. The normal cornea is a unique tissue in that it is normally crystal clear and mostly void of blood vessels, except for the very outer margins where small ciliary blood vessels may extend less that 1/2 mm from the periphery. Because 99% of the cornea does not have a blood supply, the normal mechanisms of the body to fight infection and contamination of this tissue is greatly diminished. Therefore one can appreciate the importance in preventing any contamination and entrapment of contaminants within the flap/bed tissues and interface. The adage "an ounce of prevention is worth a pound of cure" is very applicable here.

An uncontained surgical field, as is the case with a conventional LASIK operation, may un-necessarily expose the highly absorbent stromal corneal tissues to contact (contamination) with the edges of the lid speculum, lid margin meibomian gland secretions, lashes, conjunctiva, and surgical field fluid micro-debris.
(Illustration 5)

LAHayeSIK™ - With LAHayeSIK™, the surgical field is downsized to the patient’s cornea. The LAHayeSIK™ Handpiece establishes a concise surgical field boundary around the corneal limbus (Illustration 6)

The LAHayeSIK™ Handpiece is designed to provide containment of the cornea, corneal flap and corneal flap bed from exposure to and direct contact with the conjunctiva, lid margins, lashes, lid speculum blades, edges of the surgical drapes, and backwash of meibomian gland secretions and surgical fluid back wash. The following patented features accomplish LAHayeSIK™ down sizing and containment of the LASIK surgical field.

1. Lower Ring: The Lower Ring of the LAHayeSIK™ Handpiece is designed to contain the downsized surgical field thereby minimize backwashing of cul de sac fluids into the stromal bed by the following means:

• Corneal barrier created by the inner upper edge of the circumferential opening in the lower ring.
• Globe barrier created by the circumferential lower edge of the fixation ring against the globe.
• Conjunctiva barrier created by the mid-spaced region inside lower ring and the conjunctiva.

2. Cylinder Wall: The wall of the body of the LAHayeSIK™ Handpiece is designed to form a "cylinder wall" around the cornea. The cylinder wall provides a physical barrier to minimize interference and contact with from the eyelids, eyelashes, and lid speculum. (Illustration 6)

3. Platform: The patented LAHayeSIK™ platform is contained within the cylinder and provides an area for temporary placement of the flap above the level of the stromal bed thereby potentially reducing direct contact of the flap with lashes, lid margins, lid speculum, drape edges, and cul de sac fluids. (Illustration 6)

4. Preemptive Aspiration Function: The preemptive aspiration function of the LAHayeSIK™ Surgical System removes fluids from the lowest point (lower than the stromal bed and the flap lying on the platform) within the cylinder body of the handpiece, thereby minimizing backwash or "creep" of fluids onto the open stromal tissues. (Illustration 7)

The patented design features of LAHayeSIK™ Surgical System downsize and contain the LASIK surgical field to reduce backwash of fluids onto the stromal tissues and minimize interference from eyelashes, and lid margins throughout the entire Stage II of LASIK, from surgical incision exposure to surgical incision closure.

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