Objective classification of zonular weakness based on lens movement at the start of capsulorhexis

Abstract

PurposeTo quantify zonular weakness based on lens movement at the start of continuous curvilinear capsulorhexis (CCC) and establish a classification system for it.SettingKozawa Eye Hospital and Diabetes Center, Mito, Japan.DesignRetrospective interventional case series.MethodsWe examined 402 consecutive eyes of 316 patients who underwent CCC, phacoemulsification and aspiration (PEA), and intraocular lens (IOL) implantation. The movement of the lens capsule was measured using images from video recordings of the CCC procedure. Zonular weakness was classified based on the shifted distance: Grade I, less than 0.20 mm; Grade II, 0.20–0.39 mm; and Grade III, greater than 0.40 mm. For each of these grades, we examined the use of the capsule stabilization device during PEA, the surgical procedure for lens removal, and IOL fixation.ResultsWe classified 276 eyes (68.6%) as Grade I, 102 eyes (25.4%) as Grade II, and 24 eyes (6.0%) as Grade III. As the grade increased, the use of the capsule stabilization device in PEA and scleral suture fixation of IOL increased.ConclusionsZonular weakness was quantified by measuring the movement of the lens capsule. An objective classification of zonular weakness based on lens movement may be useful for selecting the appropriate device and procedure during cataract surgery.

A Review of Complicated Cataract in Retinitis Pigmentosa: Pathogenesis and Cataract Surgery

“…Early vitreal liquefaction and irregular vitreal scaffolding in RP patients are possibly associated [ 12 ]. Considering lots of challenges brought by zonulopathy when undergoing cataract surgery, including capsular rupture, vitreous prolapse [ 69 ], nucleus drop [ 70 ], and early anterior contraction with a resultant decrease in vision and IOL dislocation [ 67 , 68 , 71 ], the surgeons should be prepared to preoperatively identify these signs suggesting a possibility of zonular weakness, such as lens subluxation, zonular dialysis, or phacodonesis, which can allow for some protective measures discussed in part of capsular tension ring (CTR) [ 16 , 70 ]. However, these signs usually indicate severe zonular weakness.…”

“…However, these signs usually indicate severe zonular weakness. Intraoperative assessment is considered as best to determine minor and moderate zonular weakness through surgical maneuvers and observations [ 70 ].…”

Effect of capsular tension ring implantation on capsular stability after phacoemulsification in patients with weak zonules: a randomized controlled trial. CTR implantation in cataract patients with weak zonules

“…Zonules are considered weak if zonular fibers are looser than normal, making them more susceptible to damage or rupture, or if they have already been ruptured. Zonular weakness makes the lens unstable, which can complicate intraocular procedures such as cataract surgery and increase risk of intraocular lens (IOL) dislocation [ 1 ]. IOL dislocation is a severe complication after cataract surgery, and it necessitates additional surgery to replace the IOL using different techniques, which can be very invasive for the eye.…”

“…The chance of capsular shrinkage is also higher after surgery [ 6 , 17 , 18 ]. Capsular shrinkage increases tension on zonular fibers, further lengthening and weakening them [ 1 , 4 , 6 ].…”

Characteristic Manifestations regarding Ultrasound Biomicroscopy Morphological Data in the Diagnosis of Acute Angle Closure Secondary to Lens Subluxation

“…To our knowledge, there are few related clinical studies available on sensitive indicators for diagnosis of lens subluxation. Yaguchi et al [19] indirectly determined the degree of relaxation of the zonule by observing the degree of lens displacement during anterior capsular tear before cataract surgery. This can provide clinical guidance for the selection of surgical equipment and surgical methods.…”