Wehner spoon enhances nuclei handling in laser cataract procedure, surgeons say

The device shortens time for laser phaco, increases safety and allows more manageability of nuclear material during cataract surgery.

Issue: December 15, 2001

AMSTERDAM — Cracking and managing nuclear material during laser phacoemulsification is more efficient with the Wehner spoon, according to two surgeons with experience using the device. The irrigation hand piece was recently added to the Dodick Laser Photolysis System from ARC Laser Corp.

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The spoon is seen with a stream of irrigation fluid. An artificial piece of lens material is shown.

With this tool, designed by Wolfram Wehner, MD, surgeons can handle several grades of nuclei, its developers say. The Wehner spoon is a stainless-steel infusion handpiece that fits through a 1.4-mm incision. A sharpened, plate-like tip on the end of the spoon is used for cracking and scooping lens material.

According to Dr. Wehner, using this tool during laser phaco surgery provides the surgeon with higher accessibility to nuclear particles.

With the Dodick system, two instruments are used concurrently through separate small incisions; one delivers infusion while the other delivers laser energy and aspirates fluid and lens material. With the Wehner spoon integrated into the infusion instrument, surgeons can crack, collect and place nuclear fragments next to the laser probe for aspiration.

“It’s technology that’s been enhanced by Wehner’s technique,” said Jack Dodick, MD, designer of the Dodick laser system, here at the European Society of Cataract and Refractive Surgeons meeting.

The Wehner spoon was added to the Dodick system in early 2001. The Dodick system was launched in Europe in 1998 and was approved by the Food and Drug Administration in 2000.

“The Wehner spoon allows a surgeon to crack and manipulate certain fragments, often very dense pieces of the nucleus, and feed them, with its tip, to the laser probe,” said Bob Childs, national sales manager for ARC Laser Corp., manufacturer of the Wehner spoon and the Dodick Laser Photolysis System.

Enhancing energy

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The lens is lifted before cracking (left). The lens material has been broken into parts (right). The spoon is positioned directly under the laser handpiece.

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The spoon keeps the lens material at the aspiration hole of the laser handpiece.
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The lens is cracked between spoon and laser handpiece using the pointed end of the spoon.
drawing
The positions of the spoon and laser handpiece are shown; the infusion stream is channeled toward the posterior capsule. The water circulation in the capsular bag is shown by the blue arrow.

“The [Wehner spoon] dramatically reduces the amount of energy that goes into the eye, as we continue to search for ways to ablate the nucleus with less and less energy,” Dr. Dodick said.

“The spoon is efficient because it keeps the nuclear pieces at the aspiration mouth,” Dr. Wehner said. “The laser pulses tend to push the nuclear material away from the probe mouth. The spoon keeps lens material at the mouth for efficient ablation and aspiration,” Dr. Wehner said.

With less searching and grabbing for nuclear material, there is less corneal damage, he said.

Fluidics

An additional feature of the Wehner spoon is improved fluidics.

“It channels the infusion stream ... directly toward the posterior capsule,” Dr. Wehner said.

The posteriorly directed infusion serves two functions, he said. First, it keeps fluid turbulence out of the anterior chamber.

“This is an additional safety feature of the Wehner spoon,” he said.

Second, the infusion continually bathes the posterior capsule, polishing the capsule during surgery.

The technique

Dr. Wehner uses a diamond knife to make two 1.4-mm to 1.5-mm incisions at about 5 o’clock and 1 o’clock. An additional, optional 0.8-mm incision can be created through which to perform capsulorrhexis.

The infusion cannula enters through the 5 o’clock incision, and the ablation/aspiration cannula enters at 1 o’clock. For soft nuclei (1+ to 2+), a nuclear bowl technique can be used to emulsify the lens in the capsular bag. Denser nuclei require fracturing with the spoon.

For fracturing, the lens is lifted out of the bag with vacuum, and the tip of the Wehner spoon is placed underneath. The lens is fractured by bringing the two probes together. This maneuver is called back-cracking.

Once the nucleus is back-cracked, one fractured segment is supported by the spoon and ablated and aspirated using the laser probe. The ablation proceeds parallel to the lens fibers, not perpendicular. Dr. Wehner said that 3+ and 4+ lenses can be addressed using this technique.

“This system can handle approximately 60% of all cataracts presented, but not brunescent lenses, for which there is an ultrasonic attachment,” Dr. Dodick said.

Dr. Wehner performs bimanual cortical cleanup without these same probes.

For Your Information:

Wolfram Wehner, MD, chairman of Maximilians Augenklinik, may be reached at Erlenstegenstr 30, 90491 Nürnberg, Germany; (49) 9-112-2968; fax: (49) 9-112-448655; e-mail: Dr.W.Wehner@t-online.de. Dr. Wehner has no direct financial interest in the products mentioned in this article, nor is he a paid consultant for any companies mentioned.

Jack Dodick, MD, may be reached at 535 Park Ave., New York, NY 10021; (212) 288-7638; fax: (212) 832-0640; email: jackdodick@aol.com.

Bob Childs is national sales manager for ARC Laser Corp. He can be reached at phone/fax (800) 500-2979.

For information on the Dodick Laser Photolysis System, contact ARC Laser Corp., 2417 South 3850 West., Salt Lake City, UT 84120; (801) 972-1311; fax: (801) 972-5251; Web site: www.arclaser.com.