High speed vitreous cutter improves efficiency in vitreoretinal surgery

Higher cutting speed increases efficiency and reduces risk of posterior segment procedures.

Since its introduction by Robert Machemer in the early 1970s, vitreoretinal surgery has evolved to become a routine procedure. Advances in technology have allowed not only increased surgical efficiency, but also significant enlargement of the field of indications of this sophisticated surgery.

In the 1980s a major step to improvement of vitreoretinal surgery was achieved with the introduction of perfluorocarbon liquids by Stanley Chang, MD. In the 1990s another important step was the introduction of several wide angle viewing systems.

At the beginning of the new millennium, the introduction by Bausch & Lomb of the Lightning high speed vitreous cutter (HSVC) (Bausch & Lomb Surgical, Claremont, Calif.), to be used with the Millennium surgical unit, may be the next main step in the accomplishment of up-to-date vitreoretinal surgery.

As its name implies, the major difference between this vitreous cutter and others is the very high speed of cutting, which, coupled with a moderate level of aspiration, allows a complete vitrectomy to be performed with minimal tractional forces and motions of the intraocular structures. A disposable tip to be used with a reusable handpiece warrants consistent high quality cutting. A good setting to start with on the HSVC may be a cutting rate of 1500 cpm and an aspiration level of 150 mm Hg, but after a short period of use vitreoretinal surgeons will find the best setting for their own practices.

Superior to conventional cutters

This new vitreous cutter has shown its superiority to conventional vitreous cutters in an impressive number of operating situations. The Lightning HSVC is especially useful for repair of retinal detachments complicated by primary or iatrogenically induced proliferative vitreoretinopathy (PVR). The complete shaving of the vitreous base, which is mandatory in this situation, can be accomplished with minimal motion of the detached retina and a reduced risk of iatrogenic retinal tear.

The Lightning HSVC is also useful in the treatment of pediatric complicated retinal detachments, where posterior vitreous detachment is often incomplete or absent. The risk of tearing the mobile retina when detaching a strongly adherent vitreous is greatly reduced when using the HSVC with a low aspiration level. In this rare pediatric condition, a low level of aspiration will slow down the surgery but significantly improve the safety of the procedure.

Another excellent indication of the Lightning HSVC is for repair of giant tear retinal detachments. It allows the surgeon to vitrectomize very close to the mobile edge of the giant tear, because the high cutting speed, coupled with the distant location and moderately small size of the guillotine aperture, is much more favorable to vitreous gel than retinal tissue capture.

Finally, the Lightning HSVC may be very useful in diabetic proliferative retinopathy surgery, especially when complicated by a combined, and quite mobile, retinal detachment. The instrument may be used safely to perfectly shave fibrovascular proliferation even when the points of contact between the retina and the proliferative tissue are large. Once again, the risk of iatrogenic retinal tears may be reduced with the HSVC compared to some dissection techniques using scissors.

Case report

A 5-year old girl was recently admitted for treatment of a giant tear retinal detachment in the right eye, a –20 D myopic eye. She had been followed since early childhood for bilateral severe myopia and congenital glaucoma. Glaucoma had previously been surgically treated with bilateral trabeculectomy and with trabeculotomy in the fellow eye, and was medically controlled.

Ophthalmoscopic examination of the right eye under general anesthesia revealed a total retinal detachment with a 320° retinal tear and moderate PVR. Preoperatively, the vitreous was shown to be only partially detached, and strongly adherent not only to the retina and the edge of the giant tear but also to the posterior lens capsule.

During the pars plana lensectomy, vitreoretinal traction allowed the extension of the giant tear to 360°. At this point, the Lightning HSVC proved very useful in removing the adherent vitreous gel without compromising the retinal tissue.

After completion of the vitrectomy with the HSVC under a wide-angle viewing system (Reinverting Operating Lens System, Volk Optical Inc., Mentor, Ohio), the retina was flattened with perfluorodecaline (DK-line, Chauvin, Labège, France), and endophotocoagulation with an argon laser (HGM, Salt lake City, Utah) were applied to the 360° edge of the retinal tear. Surgery ended with a pars plana peripheral inferior iridectomy and perfluorodecaline/silicone oil exchange (Adato Sil-ol 1000, Bausch & Lomb Surgical). The short-term postoperative course was uneventful.

Conclusion

The Lightning HSVC is a useful adjunct to the equipment of the vitreoretinal surgeon. Its main advantage is that it greatly reduces the risk of iatrogenic retinal tears in the most complicated vitreoretinal procedures.

In the future, it may be interesting to compare the qualities of the high speed vitreous cutter with those of the not yet commercially available erbium:YAG laser unit and handpiece for vitrectomy.

For Your Information:

• Anne-Catherine Gribomont, MD, is head of the Vitreoretinal Surgery Unit, Ophthalmology Department, Cliniques Universitaires St-Luc, Ave. Hippocrate, 10, B1200 Brussels, Belgium; (33) 32 2 764 1950; fax (33) 32 2 7642988. Dr. Gribomont has no direct financial interest in the products mentioned in this article, nor is she a paid consultant for any companies mentioned.

• Bausch & Lomb Surgical, makers of the Lightning HSVC can be reached at 55 West Arrow Hwy., Claremont, CA 91711; (800) 423-1871; fax: (909) 399-1525.