The device in clinical practice
I have used the new-generation ring in over 60 FLACS patients over the past 2 years. Below are a few interesting cases I have come across.
Case Study 1
This 67-year-old male presented to me with a history of pseudoexfoliation syndrome. He was taking tamsulosin and had a pupil size of 5 mm. Given the four-fold higher risk of intraoperative floppy iris syndrome (IFIS) in eyes with pupils smaller than 7 mm compared with pupils of 8 mm or more, the Malyugin ring was chosen as the device most likely to minimise the risk of adverse intraoperative events in this patient.
A 2-mm corneal incision was created and the viscoelastic injected. I then injected the ring, engaging the distal scroll first, and then the lateral scrolls and proximal scroll. I repositioned the ring to centre it and then placed the patient under the laser.
I was able to create a capsulorhexis of 4.7 mm because the ring provided enough space and allowed me to maintain the distance between the edge of the iris and the capsulorhexis (therefore avoiding damaging the iris with the laser).
Case study 2
A 46-year-old female attended my clinic with a history of corneal transplant to treat keratoconus. She had a very small pupil – no more than 2.0 mm, cataracts, 12 D of against-the-rule corneal astigmatism and she needed a custom-made IOL to be implanted.
On assessment in the operating room at the beginning of the surgical step of the procedure, her small pupils responded slightly to intracameral phenylephrine and OVD. However, the level of enlargement achieved was not enough to safely proceed with the surgery.
It is in situations like this that the Malyugin ring is invaluable. Insertion of the ring achieved sufficient pupil expansion, allowing suitable exposure of the capsulotomy for thorough assessment of its adequacy. In my opinion, a good capsulotomy is one that is free of tags and adhesions within the capsule and capsulotomy flaps.
On confirming that the capsulotomy was indeed suitable, I was able to proceed with removal of the opaque lens and replaced it with the custom-made toric IOL.
Adequate pupil expansion is critical for toric IOL alignment. After the IOL is oriented along the strong corneal meridian, OVD is removed from the capsular bag—especially from behind the IOL—to ensure that the lens will not rotate postoperatively.
However, OVD must not be removed from the anterior chamber at this time because its presence is required for safe removal of the ring. Once the ring has been withdrawn from the eye, residual OVD can then be aspirated and the wound’s water tightness checked.
Case study 3
In this case involving a 79-year-old male with a pupil size of 5.5 mm, the pupil remained stable and of normal size during femtosecond laser application and the initial steps of phacoemulsification, allowing me to aspirate the cortical material. But on starting to open the cleavage planes created with the laser, the pupil began to collapse and constrict – a classic sign of IFIS.
I initially chose to proceed by injecting viscoelastic through the paracentesis in order to expand the pupil a little, but I was met with constant pupillary constriction – most probably due to the combined effect of IFIS and the laser encouraging prostaglandin release into the channel. Given the unrelenting constriction, I chose to change tactics and use the Malyugin ring, knowing it would be a safer and more predictable option than trying to irrigate and aspirate at least some of the cortical material.
On injecting the ring, the pupil stabilised and expanded, allowing safe completion of the procedure. I could then dry aspirate the cortical material, insert the IOL into the capsular bag and remove the ring.