A Novel Technique To Clean Lasik Interface Under Positive Hydro Pressure

Interface debris is a ubiquitous complication encountered after LASIK surgery which can lead to less than desirable outcomes. Interface debris may also hinder the healing process resulting in delayed visual rehabilitation causing glare, halos and blurred vision. The novel technique to clean LASIK interface under positive hydro pressure aims to minimize the occurence of persistent interface particles.

In a period of one year, 114 eyes of 57 patients undergoing LASIK surgery were included in a prospective study with their informed consent. Group A consisted of 57 eyes in which the LASIK interface was cleaned by the traditional cannula method and group B consisted of 57 eyes in which the LASIK interface was cleaned under positive hydro pressure. Effectivity of both the techniques was compared by studying the presence of interface particles observed under slit lamp post operatively.

 After the step of laser ablation in LASIK procedure, one eye of each patient underwent LASIK interface cleaning with the traditional method of irrigation by cannula and in other eye the interface was cleaned under positive hydro pressure of free flowing balanced salt solution for 5-8 seconds. Corneal flap was reposited under positive hydro pressure with the help of a spatula and was ironed with a merocel sponge ensuring its correct orientation and absence of striae. Interface was examined for any residual debris intraoperatively under microscope. All the patients were examined immediately after the procedure and on post-operative day 1 on slit lamp for the presence of interface debris.

In group A where LASIK interface was cleaned with traditional cannula method, 14.03% patients had metallic particles, 7.01% had cotton fibre and 1.75% had meibomian gland secretions in the interface. In group B where LASIK interface was cleaned under positive hydro pressure, 7.14% patients had metallic particles, 3.50 % had cotton fibre and no patient showed the presence of meibomian gland secretions in the interface.

The positive pressure from non-turbulent sterile irrigation prevents backwash of pooled fluid onto the surgical site thus significantly minimizing the presence of interface debris. Cleaning of LASIK interface under positive hydro pressure helps to rinse the laser and keratome generated micro debris, contaminants and foreign materials from the exposed surgical zone more effectively as compared to the traditional method of interface irrigation using a cannula.