Microincision vitrectomy surgery technique evolves

Editor's Note: There has been a continuous evolution of improvement for surgeons and patients who undergo pars plana vitrectomy. The surgical technology and hand-held instrumentation have improved and the techniques have become less invasive-affording more comfort, faster healing, and potentially faster recovery of vision for patients. These advances have paralleled those seen in anterior segment cataract surgery.

Retinal surgeons continue to refine techniques to optimize the safety and efficacy of microincision vitrectomy surgery, and Sunir J. Garg, MD, FACS, highlights these advances in this column.

-Allen C. Ho, MD

Overall, patients come in on postoperative day 1 usually with minimal to no discomfort, and they are not usually troubled by slowly dissolving Vicryl sutures rubbing under their eyelids for 2 weeks. Because the incisions into the conjunctiva are smaller, there is less bleeding, which results in a better cosmetic appearance (still not as good as after cataract surgery, but for a retina surgeon, it is pretty good).

Visual recovery also seems to be faster with MIVS; the wounds are smaller and require fewer sutures so these eyes have less postoperative astigmatism. Even if sutures are required, because of the small size these wounds can normally be closed with a single simple interrupted 8-0 Vicryl suture. Recently, a colleague from Maine suggested using 6-0 plain gut sutures. Although I've just started using them, they seem to work well, and these patients seem to have even less scratchiness. (If you try this, please make sure to rinse the suture and keep it short.)

From the surgeon's perspective, there are a number of advantages to MIVS. For most cases, MIVS is faster than standard 20-g vitrectomy. With the previous-generation MIVS systems, especially 25-g, vitrectomy removal took longer, but the time saved in opening and closing the eye made the overall surgical time for "straight-forward" cases about the same or somewhat less than 20-g vitrectomy.

The new-generation MIVS systems offer 5,000 cuts-per-minute. The surgeon is able to remove the vitreous remarkably efficiently, and the vitrectomy time is better than with standard 20-g vitrectomy. For those accustomed to 20-g systems, a 20-g 5,000 cuts-per-minute probe is available, but given how efficient the MIVS systems are at this rate, 20-g vitrectomy does not distinguish itself.