Following the introduction of the CCC technique, the rate of anterior capsule tear has exhibited a decline during phacoemulsification cataract surgery [1],[6]. Nonetheless, this complication remains a recognized concern in cataract surgery. Its reported incidence varies, ranging from 0.79–5.55% [2],[3],[7],[8]. Most of these tears occur during the capsulorhexis stage of the surgery. Carifi et al.[2] noted that 54% of tears were observed during capsulorhexis, while Marques et al.[3] found that 61.9% of tears occurred at this stage. In the present study, the majority of tears occurred during the phacoemulsification and capsulorhexis stages.
In this study, a notable 38.1% of patients experienced complications involving posterior capsule rupture and vitreous loss, necessitating anterior vitrectomy. All of these patients experienced anterior capsule tears during the phacoemulsification stage. Previous research has reported posterior capsule rupture rates in the range of 24-47.6% [2],[3]. Marques et al.[3] identified posterior capsule tears occurring at stages other than capsulorhexis, with a majority (60%) arising during IOL implantation in patients with anterior capsule tear. Conversely, Carifi et al.[2] demonstrated that the rates of posterior capsule rupture and vitreous loss did not vary significantly based on the timing of the anterior capsule tear.
Common causes of anterior capsule tears during the capsulorhexis stage include poor visualization of the anterior capsule and unintended extension of the capsulorhexis edge. Techniques to address these challenges involve the use of trypan blue to enhance capsulorhexis visibility (particularly in cases with white or brunescent cataracts) and ophthalmic viscoelastic devices (OVDs) to flatten the convex anterior surface of the crystalline lens and minimize peripheral capsulorhexis edge extension [3],[9].
During other stages of cataract surgery, strategies such as minimizing excessive nucleus manipulation, employing the chopping technique for nucleus fragmentation, executing slow-motion phacoemulsification, preventing engagement of the I/A tip with the tear's edge, and filling the capsular bag with OVD before IOL implantation are advised to reduce the occurrence of anterior capsule tears and their serious ramifications, especially when tears extend to the posterior capsule [2],[3],[6],[9],[10]. In this study, surgeons attributed anterior capsule tears to factors such as the need for high phacoemulsification parameters (for dense nuclei), inadvertent capsulorhexis extension toward the anterior zonules (notably in mature cataracts), and engagement of the capsulorhexis edge with instruments during phacoemulsification.
Aphakia was not observed in any eyes after posterior capsule rupture and vitreous loss in this study. In previous research involving patients with anterior capsule tears during phacoemulsification cataract surgery, the rate of remaining aphakic after the primary procedure ranged from 0–4.6% [2],[3]. The surgeon's judgment during the procedure significantly influences IOL-related decisions in cases of posterior capsule rupture. The assessment hinges on the extent of capsule bag and ciliary sulcus damage, procedure safety, postoperative complication risk, and the necessity of further intraocular interventions [2].
Carifi et al.[2] reported a considerable visual improvement (BCVA gain ≥ 3 lines) in a majority (71%) of eyes with anterior capsule tears during phacoemulsification cataract surgery. Similarly, the current study indicated that nearly all cases (except for one with postoperative RD) achieved a BCVA improvement of at least 3 lines at the 12-month follow-up.
Over the long term, SIA is primarily influenced by the nature of corneal wound healing after cataract surgery. Characteristics of the incision (including shape, location, depth, and direction) can impact wound healing and consequent SIA. Furthermore, suturing the incision and the technique employed can induce astigmatism [11]–[15]. Other factors linked to higher SIA include significant preoperative corneal astigmatism and advanced age [11]. Overall, the SIA at the 12-month mark did not exhibit statistical significance. However, it's possible that these values might increase in subsequent years, as demonstrated in prior literature [11],[16]. Although this study found that intraoperatively complicated cases, especially those with sulcus-implanted IOLs, had higher SIA values than uncomplicated eyes, the small sample size in these subgroups precluded statistical comparisons. All intraoperatively complicated cases underwent suturing of the main clear cornea temporal incision at the conclusion of the surgery, which may have contributed to corneal astigmatism. However, the removal of these sutures 1–3 months post-surgery is unlikely to result in significant astigmatism over the long term.
This study has certain limitations. The small sample sizes of subgroups, particularly cases with intraoperative complications, prevented statistically meaningful comparisons of tear characteristics, surgical outcomes, and complications. Moreover, only SIA was evaluated, with other refractive outcomes of the subgroups remaining unexplored. As such, larger sample sizes and rigorous statistical analysis are warranted to validate the study's findings.
In conclusion, the occurrence of anterior capsule tears during cataract surgery can significantly impact the quality of the procedure, leading to various complications, including extension of the tear to the posterior capsule and vitreous loss, as well as other intraoperative and postoperative morbidities. To mitigate the consequences of this complication, revisiting cataract surgery stages to avoid engagement of the tear's edge is recommended.