Bag-in-the-lens intraocular lens in paediatric cataract surgery: intraoperative and postoperative outcomes

The prevalence of visual axis opacification in the Swedish Pediatric Cataract Register

PURPOSE

To report on the occurrence of postoperative visual axis opacification (VAO) in children younger than 5 years of age operated for cataract in Sweden, and to analyse correlations with age at surgery and surgical method.

METHODS

Data were derived from the Swedish Pediatric Cataract Register (PECARE). All children operated on between 1 January 2007 and 31 December 2020 were included. Follow-ups at 1, 2 and 5 years of age were analysed.

RESULTS

Cataract surgery were performed on 770 eyes belonging to 549 children (n = 282 boys, 51.4%); 327/770 (42.5%) of the children underwent surgery before 3 months of age and 216/770 (28%) before 6 weeks of age. Data on 881 follow-up visits were registered. At the follow up-visits at 1, 2 and 5 years of age, VAO was present in 154/349 (44.1%), 41/323 (12.7%) and 25/208 (12%). The majority of the children with VAO underwent cataract surgery before age 6 months, with a predominance before age 2 months. Primary IOL was implanted in 601/770 (78%) of eyes; 40.8% had an acrylic one-piece lens, 31.8% had a bag-in-the-lens IOL, 21.9% were aphakic and 5.2% had an acrylic three-piece lens. Implantation of a bag-in-the-lens IOL was related to a significantly lower occurrence of VAO compared to other types of IOL, including aphakia (p < 0.0002).

CONCLUSION

Our results are in accordance with the literature. Primary bag-in-the-lens IOL implantation before 2 years of age seems adequate and safe, with a low occurrence of VAO, and can thus be continued as routine in Sweden.

Posterior Capsular Outcomes of Pediatric Cataract Surgery With In-The-Bag Intraocular Lens Implantation

AIM

To investigate the change of posterior capsular outcomes of pediatric cataract surgery with primary in-the-bag intraocular lens (IOL) implantation.

METHODS

We conducted a case series of pediatric cataract children who underwent cataract extraction with primary in-the-bag IOL implantation, posterior capsulorhexis or vitrectorhexis, and limited anterior vitrectomy at the Eye Hospital of Wenzhou Medical University between 2016 and 2019. Digital retro-illumination photographs of pediatric eyes were obtained at baseline and 6 months, 12 months, and the last visit postoperatively. Capsular outcomes of the posterior capsular opening area (PCOA) and lens reprolifration area at those time points were compared. Correlations between the PCOA and influential factors, such as age at surgery, axial growth, and follow-up duration, were analyzed. The study was registered at register.clinicaltrials.gov (NCT04803097).

RESULTS

Data of 23 patients (27 eyes) were used in the final analysis. During follow-up, the PCOA enlarged at a rate of 0.29-0.32 mm²/month during the first six months postoperatively and 0.05-0.08 mm²/month over the next 1-2 years. Six months postoperatively, the PCOA enlargement statistically and positively correlated with the follow-up duration and axial growth. The area of lens reprolifration was 0.46 ± 1.00 mm² at six months postoperatively and then remained stable.

CONCLUSION

The PCOA enlarged rapidly within the first six months after the pediatric cataract surgery with primary IOL implantation. Six months postoperatively, the enlargement of PCOA was positively correlated with follow-up duration and axial growth. Posterior capsulorhexis or capsulectomy should be performed with a diameter of 3.0 to 4.0 mm for good visual axis transparency and the protection of in-the-bag IOL.

NIR-triggered drug delivery system for chemo-photothermal therapy of posterior capsule opacification

Posterior capsule opacification (PCO) is the most common complication after cataract surgery and is likely to cause the second loss of vision. Pharmacological PCO prophylaxis has been proved to be effective, yet no clinical option is available due to the lack of a suitable mode of administration. In this work, we propose a unique concept of NIR dual-triggered drug release from black phosphorus (BP)-based implantable intraocular lens (IOL) for controlled drug release and chemo-photothermal combination therapy of PCO. Here, IOL is used as a "reservoir" of doxorubicin-loaded black phosphorus (BP-DOX), and BP is used as NIR activation agent for controlled drug release and photothermal therapy. This BP-DOX integrated IOL, namely BP-DOX@IOL, shows the characteristics of good transmittance, good mechanical property, NIR dual-triggered drug release behaviors, and excellent photothermal efficacy. In vivo studies reveal that there is no PCO occurrence in rabbits' model by using BP-DOX@IOL combined NIR irradiation, which exhibits distinct superiority on inhibiting PCO than the control group (100% PCO occurrence) 28 days post-surgery. This novel IOL drug delivery system would be a promising strategy for the future clinical application for PCO prophylaxis and treatment.