December 2018

CATARACT

YES connect
MSICS and its place in the hands of young eye surgeons


by Liz Hillman EyeWorld Senior Staff Writer


A preoperative black lens with posterior synechiae, shallow anterior chamber in a 60-year-old patient with retinopathy of prematurity

Extracted nucleus following sphincterotomies, can-opener capsulotomy, and MSICS through a scleral pocket temporal incision


Incision closed with a single 10-0 nylon suture
Source (all): David Chang, MD

Most ophthalmology residency programs do an excellent job teaching residents modern cataract surgery. Trainees are getting more and more exposure to the latest technologies and techniques including the femtosecond laser, iris expansion devices, specialty intraocular lenses, etc. While staying cutting edge is important for any young surgeon, it is also important to know how to deal with complications and how to handle unique situations. In some circumstances, MSICS can be a safer way to remove a cataract, and residency or fellowship is the perfect time to tackle challenging cases with the supervision of an attending surgeon.
I strongly recommend young surgeons make it a priority to learn MSICS, especially if they are interested in serving abroad in developing countries at some point in their career. Another benefit of learning MSICS is that it can help hone other skills such as creation of a self-sealing scleral tunnel incision.
In this month’s “YES connect” column, we discuss MSICS with experts in the field and share the importance of learning this surgery. I hope that after reading this article, you will consider making it a priority to learn MSICS.

Samuel Lee, MD,
YES connect co-editor


Experts agree that manual small incision cataract surgery has a role in regular practice and training programs, even in developed countries

While phacoemulsification has been the gold standard of cataract surgery for decades, a low tech procedure—manual small incision cataract surgery (MSICS)—has carved out a place for itself, especially in developing countries where phaco is not as readily available. However, some think there is a place for it in the U.S. as well.
“I use MSICS as a planned primary procedure in my own practice several times each year,” said David F. Chang, MD, clinical professor, University of California, San Francisco. “It is sometimes safer than phaco for the most advanced, ultrabrunescent cataract, particularly when comorbidities, such as phacodonesis, corneal endothelial dystrophy, or pupillary membranes and synechia, are present.”
For similar reasons, Julie Schallhorn, MD, assistant professor of ophthalmology, University of California, San Francisco, and Matthew Oliva, MD, Medical Eye Center, Medford, Oregon, think MSICS should be incorporated into residency training programs, even if phaco is the most common course of cataract surgery.
“I think it is critical that residents learn to make self-sealing scleral tunnel incisions and understand how to deliver a nucleus manually,” Dr. Oliva said. “This is a critically necessary skill in cases with a zonulopathy or if a phaco case is going poorly. I routinely do MSICS in my clinical practice several times a month for dense or unusual cataracts. The corneal endothelium does much better with MSICS than phaco in rock hard cataracts.”
In addition to finding it valuable in dense cataract cases, Dr. Schallhorn pointed out that MSICS combines many surgical techniques that are important for any anterior segment surgeon to know.
“For this reason, we start residents with MSICS as their first cataract surgeries as primary surgeon in the first year of residency. We begin the year with an intensive, week-long wet lab introduction to microsurgery and MSICS,” Dr. Schallhorn said.
There is a bit of a learning curve to MSICS, Dr. Chang said, but it’s less steep for surgeons who have already learned large incision manual extracapsular cataract extraction.
“Large incision manual ECCE should ideally be a part of everyone’s surgical armamentarium,” Dr. Chang said, explaining how it can be used with extreme zonulopathy, a zonular dialysis, or converting from phaco following a presumed posterior capsular rupture. “When converting from phaco, one can abandon the phaco incision and make a traditional large limbal incision superiorly,” he added. “With a soft eye, it is difficult to make the large scleral pocket incision that is required for MSICS.”
However, most residents aren’t learning ECCE nowadays.1 Dr. Schallhorn, for example, said she only learned MSICS in residency and it is the only extracapsular cataract surgery that she performs.
“The major difference between these two procedures is the incision size and structure. With MSICS, you create a ‘frown’ scleral tunnel incision size that is often times self-sealing,” Dr. Schallhorn said. “During nuclear delivery, the lens will mold to fit the incision. With traditional extracap, the incision is more anterior and much larger, exposing the eye to longer periods of hypotony and requiring multiple sutures for closure.”
Regarding the learning curve, Lynds et al. performed a retrospective case series looking at the outcomes of resident MSICS at a Dallas hospital.2 The investigators concluded that the learning curve appeared most tied to the wound construction, but the procedure was safe and efficacious on the whole.
“With several advantages over phacoemulsification, such as cost and ability to remove very dense nuclei, manual SICS will play a valuable role in cataract surgery,” Lynds et al. wrote.

How to perform MSICS

Dr. Oliva’s first piece of advice for learning MSICS is to work with an experienced MSICS practitioner who can step into the case if needed. Start with easy cases, those with good exposure, dilation, and mature cataracts, avoiding micropupils, loose zonules, and pseudoexfoliation cases early in the learning curve.
“One of the challenges of MSICS for the beginning surgeon is that complications to the eye can be quite severe,” Dr. Oliva said. For example, poor wound construction can lead to Descemet’s detachment or iris trauma.
Another pearl he offered is to grasp the eye just lateral and posterior to the wound edge—rather than grasping the wound itself—and rotate it downward with 0.12 forceps.
For the wound, Dr. Chang constructs an 8-mm temporal scleral tunnel incision, dissecting it anteriorly into clear cornea with a crescent blade. He finds the can-opener capsulotomy useful after staining, especially because of the comorbidities generally associated with these cases. Dr. Chang hydrodissects the nucleus with irrigation from a Simcoe I/A tip, which he also uses to help extract the nucleus and remove cortex. Dr. Chang will usually implant a large optic PMMA IOL, such as the CZ70BD (Alcon, Fort Worth, Texas), and will often close the incision with a single interrupted 10-0 nylon suture.
Dr. Oliva finds that if the wound is carefully constructed, there is typically no need for a suture, though one can be placed if the surgeon is worried about inducing excessive astigmatism, especially with superior incisions. Using a diamond crescent blade, which he said makes the smoothest tunnels and improves wound closure, Dr. Oliva creates a straight partial thickness groove 1 mm posterior to the limbus approximately 7 mm in length. Dissection is then carried out within the sclera into clear cornea for 1–2 mm before entering the eye. He said the internal diameter of the incision should be created with a keratome and measure close to 10 mm to give the wound a funnel shape. For the capsulotomy, Dr. Oliva said he finds the V-capsulotomy best suited for dense cataract cases with small pupils.
“Early in training, I advise viscoelevation of the nucleus into the anterior chamber prior to delivery from the eye,” Dr. Oliva said. “Make sure it is above the iris, especially inferiorly, and make sure the wound is large enough. Always protect the endothelium with viscoelastic prior to delivering the nucleus. An irrigating lens loupe can be helpful early in the learning curve.”
If he’s dealing with a case of very small pupils, Dr. Oliva will often create several microsphincterotomies with Vannas scissors, which he said can facilitate the delivery of a large nucleus through a smaller pupil with minimal cosmetic effect postop. In a case of inadequate dilation, Dr. Schallhorn cautioned against using a Malyugin ring in favor of hooks instead.
“A ring will prevent you from prolapsing the lens up and can get caught on the lens loop,” she said.
At the end of the case, Dr. Oliva closes the conjunctiva with a temporal incision using cautery; with a superior incision there is generally no need to close the conjunctiva as it covers the incision naturally, he added.
Dr. Schallhorn said it is important to make the internal dimensions of your incision wider than external dimensions; this creates a funnel to help mold the lens as you remove it. Dr. Schallhorn places the apex of the frown 1 mm posterior to the limbus with the tails of the frown 2 mm posterior to the limbus for a total incision that is 8 mm long. After creating the frown incision she tunnels forward just into the clear cornea, fanning out the internal portion of the wound until it is about 11 mm wide. Once the tunnel is complete, she opens the central portion with a keratome and creates a can-opener capsulorhexis before opening the entire incision, maintaining a stable chamber. At the end of the case, after placing a three-piece IOL, Dr. Schallhorn will put in one figure-of-eight suture, even though the tunnel should be self-sealing. She closes the conjunctiva with a Vicryl suture (Ethicon, Bridgewater, New Jersey) or with forceps cautery.

Converting from phaco to MSICS mid-case, cases to avoid, and beyond

As previously mentioned, MSICS can be a valuable technique if phaco is not working for a case, such as if there appears to be zonular weakness or risk of the nucleus dropping. Dr. Schallhorn said the switch is pretty easy and starts with anesthesia. If you’re using topical anesthesia, you’ll want to give the patient a block, she said. Then, suture the main wound and move your microscope superiorly, while there is some viscoelastic in the eye to prevent hypotony.
Dr. Oliva said it is possible to remain sitting temporally and create a scleral tunnel beneath and posterior to the 2.2-mm clear corneal temporal phaco incision, but the trick is to not join the two wounds.
There are also cases where MSICS should be avoided. Dr. Oliva said he avoids this technique in those who have had glaucoma surgery and those who need combined surgery, such as a cataract DSAEK case. Dr. Schallhorn said patients with gross phacodonesis are generally not good candidates as well.
In general, Dr. Schallhorn said she thinks “there is definitely a place for MSICS” in training programs as well as in practice, even in developed countries.
“We are fortunate in the U.S. to have a hugely diverse patient population, both medically and geographically,” she said. “We see many recent immigrants with extremely dense lenses who are good MSICS candidates, and also many patients with complex medical problems that have led them to be good candidates for MSICS,” Dr. Schallhorn said.

References

1. Chen CK, et al. A survey of the current role of manual extracapsular cataract extraction. J Cataract Refract Surg. 2010;36:692–3.
2. Lynds R, et al. Supervised resident manual small-incision cataract surgery outcomes at large urban United States residency training program. J Cataract Refract Surg. 2018;44:34–38.

Editors’ note: The physicians have no financial interests related to their comments.

Contact information

Chang: dceye@earthlink.net
Oliva: moliva@cureblindness.org
Schallhorn: jschallhorn@gmail.com

MSICS and its place in the hands of young eye surgeons MSICS and its place in the hands of young eye surgeons
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