instrument insider
Limbal Relaxation Kit
By Jonathan B. Rubenstein, M.D.

The goal of cataract surgery in the year 2005 is not only to improve visual acuity, but also to provide excellent uncorrected visual acuity.

	The Limbal Relaxation Kit comes with a knife, blunt-tip caliper, gauge and fixation ring, and plastic tray.

The spherical component of this can be achieved with accurate IOL power calculations, but the astigmatic component must be managed with toric IOLs or intraoperative limbal relaxing incisions (LRIs).

I feel that I have greater control of astigmatism reduction with limbal or peripheral corneal relaxing incisions. Accutome makes the Limbal Relaxation Kit, which provides all the instrumentation necessary for intraoperative corneal relaxing incisions.

This kit consists of a Mendez-style fixation ring with 10-degree markings, a blunt-tip caliper, and a preset 600-micron double-cutting, single footplate natural diamond blade. All three of these instruments come packaged in a protective autoclavable plastic tray and are reusable.

The Knives

The Pre-Set Diamond Knife has a standard titanium handle and can be utilized for traditional limbal relaxation incisions. The diamond blade is sharp, durable, and permanently set to its 600-micron length.

The knife has a low-profile, single footplate that allows me the full view of the blade during incisions. This visualization allows me to start and stop the blade precisely.

The Shorti LRI Diamond Knife is a short-handled version of the knife. The handle length is 2.75 inches. It is ideally suited for office procedures at the slit lamp.

As these types of procedures can be challenging due to patient positioning, this knife can help surgeons maneuver more conveniently.

Doctors are given a choice between the two knives at time of purchase. The Shorti can be purchased in the kit or separately.

The Procedure

My surgical technique begins with the marking of a patient with a surgical marking pen. I mark the 6 o'clock position on the patient's limbus with the patient looking straight ahead with both eyes open.

I make a paracentesis and fill the eye with a viscoelastic until firm. I then mark the axis of plus cylinder using the fixation ring. Using the caliper, I delineate the length of the incisions and mark the limbus.

Based on the patient's age, the degree and axis of the preoperative astigmatism, and using a known nomogram, I will create either paired limbal or peripheral clear corneal incisions with the Pre-Set Diamond blade.

After using this knife, I can make my usual clear corneal entry incision and proceed with the phacoemulsification. Because peripheral relaxing incisions do not affect the spherical equivalent, the IOL power remains unchanged.

Two in One

The Limbal Relaxation Kit aids doctors with their cataract and astigmatism surgical needs. The development of both short and long handled knives gives surgeons the option to address both conditions either intraoperatively or post-operatively.

Jonathan B. Rubenstein, M.D., is the Deutsch Family Professor and vice-chairman of ophthalmology and director of refractive surgery at Rush University Medical Center in Chicago, Ill. He is also chairman of ophthalmology at Rush North Shore Medical Center in Skokie, Ill. Dr. Rubenstein has no financial interest in the Limbal Relaxation Kit.