Surgeons differ on which viewing system to use

Contact lens and noncontact systems offer distinct advantages. Which do you prefer?

While many retinal surgeons have switched to wide-field viewing systems, they differ in their preferences between contact and noncontact systems.

According to Peter Kaiser, MD, of the Cleveland Clinic’s Cole Eye Institute, an endless list of reasons exists to switch to a wide-angle viewing system for retinal surgery. He recently performed retinal surgery on a patient with trachoma, and the wide-angle system allowed him to peer around the corneal scarring and opacities to see the posterior segment.

“The case I did was impossible without a wide-angle contact lens,” Dr. Kaiser said.

Kirk Packo, MD, initially did not like the noncontact wide-field viewing systems but now uses them almost exclusively. The panoramic viewing systems allow him to see tissues on one part of the posterior segment and how pulling on them affects other more distant parts.

“The systems are absolutely spectacular for diabetic retinopathy, complex detachments or proliferative vitreoretinopathy,” he said.

Repairing giant retinal tears can be done with conventional viewing, but surgeons can do a better job with wide-angle viewing systems because the pathology mainly exists at the periphery.

“The entire retinal world will move to panoramic imaging,” Dr. Packo said. “If you use only a panoramic contact lens system, you don’t get all of the terrific advantages that noncontact systems afford.”

According to Gunter Pfeiffer, a product manager for Oculus Optikgerate GmbH (Wetzlar, Germany), “We found that a lot of surgeons are working with both systems. The slim design and the increased range of noncontact lenses for different indications enable the second generation of BIOM, the BIOMII, to meet the various demands of vitreoretinal surgery, we were told by users.”

Testing systems

---Fully equipped BIOM II. All parts sterilizable.

The Cleveland Clinic’s Cole Eye Institute received millions of dollars in funding to build a world-class eye care facility. They have bought the latest and greatest equipment throughout the facility, and they chose a contact lens system over a noncontact one, Dr. Kaiser said.

Hilel Lewis, MD, Jonathan Sears, MD, and Dr. Kaiser tested every system available and decided to use the Volk (Mentor, Ohio) AVI and Volk ROLS systems.

“We tried them all. The noncontact systems, when you go out into the periphery, don’t have anywhere near as clear a view or the stereoscopic detail that the contact lens system provides,” Dr. Kaiser said.

They also tested the binocular indirect ophthalmic microscope (BIOM) systems offered by various companies.

“We tested the BIOM system and when we went peripherally, we didn’t have the view that we wanted to peel peripheral membranes,” Dr. Kaiser said. “They are very fine membranes and very difficult to see. We couldn’t see them as well with the BIOM compared with the contact lens system.”

Surgeons at the Cole Eye Institute also worked on improving existing contact lens systems. Complicated retinal detachments and diabetic detachments accumulate blood and debris between the eye and the lens. This requires the surgeon to remove the lens, clean it and place it back on the eye.

Dr. Kaiser worked with Volk to create an irrigating handpiece, the Volk Infusion Handle, to hold the wide-angle contact lens. This alleviates the need to remove and clean the contact lens ring each time blood and debris accumulate.

The irrigating handpiece uses a meniscus of water between the cornea and the lens and constantly flushes that area. The view stays clear at all times, even in diabetic patients who bleed throughout a procedure.

“This system constantly keeps your view nice and clear. It’s really a time saver,” Dr. Kaiser said.

Noncontact used

---The compact instruments for panoramic viewing compared in size to a pen.

Dr. Packo uses the BIOM wide-field system for all but a few cases. He first tried and rejected the BIOM system 14 years ago.

“At that point, user friendliness was a real issue,” he said. “I loved the view, but it was so cumbersome.”

But a new generation of BIOM came out 5 years ago, and Dr. Packo said a sales rep offered one to him for 6 months with no obligation.

Officials at Volk Optical said that they also offer a trial period on their products.

He bought the system and uses it almost exclusively. He uses a version available from Insight Instruments of Sanford, Fla., because it has a motorized reinverter controlled by a foot pedal.

The BIOM does not need a skilled assistant, Dr. Packo said. It gives enough of a panoramic view to complete a surgery.

“If I wanted to make a movie, I might use the contact lens system. But for everyday use, it’s the BIOM hands down,” he said.

Pearls

---SDI II with BIOM II swung aside in "parking position."

Dr. Packo sets his focus at the beginning of the procedure. He sets the focus once but can still move in and out, altering the field of view. If he does not want a panoramic view, he draws the BIOM away from the eye and adjusts magnification with the microscope. If he does closer macular work, he goes to a lower field of view. “Being able to vary the field of view is a huge BIOM advantage,” Dr. Packo said.

Contact lens surgeons grow accustomed to moving instruments and not the eye. But Dr. Packo said he can move the eye under the BIOM, lower the field of view and get the benefits of a panoramic system with a good depth of focus. The wider the field of view, the more stationary he needs to keep the eye.

And, Dr. Packo said, there are disadvantages to contact lens systems. They require skilled assistants to steady the lens on the eye. Many surgeons abandon contact lens systems for this reason. “Another annoying feature of contact systems is the inversion of the x-y orientation of the microscope foot pedal. The BIOM does not cause this,” Dr. Packo said.

“If you’re a panoramic contact lens surgeon, you tend to use conventional lenses for a good portion of a case and then use the panoramic system for portions of it,” he said. “Then you go back to the regular conventional lenses, whereas the BIOM users use the BIOM from beginning to end.”

Contact lens systems also distort the view, making surgical instruments appear to bend like parentheses.

“It’s there with the BIOM but not as annoying as it is with the contact system,” he said.

The contact panoramic systems give the widest field of view, so seeing the ora serrata requires a contact system, Dr. Packo said.

“Although you may primarily use one, there are times when you may want to use the other type of panoramic system,” Dr. Packo said. “I am a 99% BIOM user, and 1% of the time or even less I will use a contact system because of the occasional advantage that the contact has over the BIOM.”

For Your Information:

• Peter Kaiser, MD, can be reached at the Cleveland Clinic Foundation, Cole Eye Institute, Division of Ophthalmology, Desk I-32, 9500 Euclid Ave., Cleveland, OH 44195; (216) 444-6702; fax: (216) 445-2226. Dr. Kaiser has no direct financial interest in any of the products mentioned in this article, nor is he a paid consultant for any companies mentioned.
• Kirk Packo, MD, can be reached at Illinois Retina Associates, SC, 71 W. 156th St., Ste. 400, Harvey, IL 60426; (708) 596-8710; fax: (708) 596-9820. Dr. Packo has no direct financial interest in any of the products mentioned in this article, nor is he a paid consultant for any companies mentioned.
• Gunter Pfeiffer can be reached at Oculus Optikgerate GmbH, Dutenhofen, Muenchholzhaeuser Strasse 29, 35582 Wetzlar Germany; (49) 641-20050; fax (49) 641-2005255. Mr. Pfeiffer is product manager for Oculus Optikgerate GmbH.
• Insight Instruments Inc. can be reached at 5400 S. Bryant Ave., Sanford, FL 32773; (800) 255-8354; fax: (407) 324-2744.

• Oculus Optikgerate GmbH can be reached at Dutenhofen, Muenchholzhaeuser Strasse 29, 35582 Wetzlar, Germany; (49) 641-20050; fax: (49) 641-2005255.
• Volk Optical Inc. can be reached at 7893 Enterprise Drive, Mentor, OH 44060; (800) 345-8655; fax: (440) 942-2257.