Tackling posterior capsule rupture
Pars plana vitrectomy can avoid enlarging posterior capsule rupture
Sooner or later every cataract surgeon will face a posterior capsule rupture. Managing the resulting vitreous loss using a pars plana, rather than an anterior, vitrectomy is more likely to produce a better outcome, Samaresh Srivastava DNB told the American Society of Cataract and Refractive Surgery 2018 Annual Symposium in Washington DC, USA.
Approaching the prolapsed vitreous from the posterior is less likely to expand the rupture than an anterior approach, noted Dr Srivastava, of Raghudeep Eye Hospital, Ahmedabad, India. As a result, a pars plana approach will more often leave enough of the capsule intact to create a symmetric, uniform IOL platform, leading to a stable, centred IOL.
While an anterior vitrectomy approach may seem more familiar to cataract surgeons, it tends to pull the vitreous body forward, often widening the rupture and pulling additional vitreous into the anterior chamber. What was a small rupture at the beginning becomes a ragged rupture by the end of the surgery, Dr Srivastava said. This additional damage to the capsular bag can require fixating the lens in the sulcus, which is less than optimal.
By contrast, a pars plana vitrectomy tends to pull the vitreous posteriorly, Dr Srivastava said.
“Whatever vitreous is there tends to prolapse back into its own cavity in a very elegant fashion.”
Often, the posterior capsule rupture can be converted to a posterior capsulorhexis to preserve the integrity of the bag. Any vitreous left behind can then be cleaned up from the anterior. A pars plana vitrectomy also can be done for tears after the IOL is implanted, he added.
BE PREPARED AND DON’T PANIC
Dr Srivastava recommended that cataract surgeons learn the pars plana approach. He also suggested preparing a vitreous loss kit, including a vitrectome, microforceps, trocar cannula system, high-molecular weight dispersive viscoelastic, triamcinolone, pilocarpine and capsular tension ring, to have on hand for every cataract surgery.
“The best thing to do in the event of posterior capsule rupture is stay calm. Do not pull out instruments in panic. The moment you pull out the instrument, the anterior chamber collapses and more vitreous prolapses out into the anterior chamber, and the posterior capsule rupture, if it was small, will become large and it will become an unmanageable situation,” Dr Srivastava warned.
Instead, lower the bottle height and inject dispersive viscoelastic to tamponade the vitreous loss, and triamcinolone to make the vitreous visible. Use good lighting and instruments to manipulate the eye to ensure all vitreous in the anterior is removed, he advised.
“A pars plana approach compared to limbal approach can give a predicable outcome and a favourable lens position most often,” Dr Srivastava concluded.
Samaresh Srivastava: email@example.com