Introduction

Posterior capsular rupture (PCR) remains one of the most signi?cant complications encountered during cataract surgery, particularly among diabetic patients. The pathophysiological changes associated with diabetes—such as altered lens metabolism, increased fragility of the posterior capsule, and chronic intraocular in?ammation—may contribute to this increased risk. In recent years, intravitreal injections of anti-vascular endothelial growth factor (Anti-VEGF) agents have become a standard treatment for diabetic retinopathy and diabetic macular edema. However, clinical observations suggest that diabetic patients who have received intravitreal Anti-VEGF injections may exhibit a higher incidence of PCR during subsequent cataract surgery, even when the last injection was administered over 12 months prior. This study investigates the relationship between the timing of Anti-VEGF injections and the incidence of PCR in diabetic patients undergoing cataract extraction.

Materials and Methods

This retrospective multicenter study included diabetic patients who received intravitreal bevacizumab (Avastin, Losantos, and similar biosimilars) between 2015 and 2018. Patients were selected from multiple ophthalmic hospitals across the region. The inclusion criteria were:

-           Diagnosed diabetes mellitus (type 1 or type 2)

-           Age between 50 and 80 years

-           History of intravitreal Anti-VEGF injections

-           Presence of cataract requiring surgical removal

A total of 1,000 patients were divided equally into four groups (250 patients per group):

Group 1: Diabetic patients who underwent cataract surgery regardless of disease duration and without requiring Anti-VEGF at the time of surgery.

Group 2: Diabetic patients who required both cataract surgery and simultaneous Anti-VEGF injection.

Group 3: Diabetic patients with a history of Anti-VEGF injection, with the last injection administered within the previous 11 months before cataract surgery.

Group 4: Diabetic patients with a history of Anti-VEGF injection, where the last injection was more than 12 months prior to cataract surgery.

All surgeries were performed using phacoemulsi?cation under local anesthesia by experienced surgeons. The primary outcome measured was the incidence of posterior capsular rupture intraoperatively.

Results

In this study, a total of 80 patients experienced posterior capsular rupture (PCR) during cataract surgery. Notably, 72 of these cases (90%) occurred in Group 4— diabetic patients who had received intravitreal Anti-VEGF injections more than 12 months prior to surgery. The remaining 8 cases (10%) were observed in Group 3.

No PCR events were recorded in either Group 1 or Group 2.

Although there is currently no widely adopted standard device for directly measuring the thickness of the posterior lens capsule, an indirect observation was made using the femtosecond laser platform. In non-diabetic patients, the laser consistently provided uniform posterior capsule measurements. However, in diabetic patients with a history of intravitreal Anti-VEGF injections, the femtosecond system often displayed variable and inconsistent readings, suggesting possible structural or biomechanical changes in the posterior capsule.

This discrepancy raises an important question for further investigation: Do intravitreal Anti-VEGF medications alter the structure or integrity of the posterior lens capsule in a way that predisposes it to rupture during cataract surgery?

Conclusion

Based on the ?ndings of this study, it is advisable to approach all diabetic patients undergoing cataract surgery with the same caution used for patients in Group 2—those requiring concurrent intravitreal Anti-VEGF injection. The data clearly demonstrate that diabetic patients with a history of intravitreal Anti-VEGF injections, especially those whose last injection occurred more than 11 months prior to surgery, are at signi?cantly increased risk of posterior capsular rupture.

While intravitreal Anti-VEGF agents remain highly effective in managing diabetic retinopathy and preserving vision, this study suggests they may have a negative structural impact on the posterior lens capsule. As such, surgeons should exercise heightened intraoperative vigilance when performing phacoemulsi?cation in these patients, regardless of the time elapsed since the last injection.

References

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