SURGERY PEARLS

There are multiple challenges to achieving a good outcome in paediatric cataract surgery. Speaking at the 26th Asia-Pacific Association of Cataract & Refractive Surgeons, Marcelo C Ventura MD, PhD, discussed some of the techniques he finds useful for minimising complications and facilitating postoperative care. Dr Ventura is vice-president of the Altino Ventura Foundation and chief of the Department of Cataract and Retina of the Hospital de Olhos de Pernambuco (HOPE), both in Recife, Brazil. He has been performing paediatric cataract surgery since 1994 and has accumulated one of the largest experiences with surgery for congenital cataract in the Americas. Considering the increased risk of posterior capsular opacification in paediatric eyes and the difficulty of doing Nd:YAG laser capsulotomy in young children, Dr Ventura performs posterior capsulotomy and anterior vitrectomy in all infantile cataract surgery cases involving children ages eight weeks to six years old. His preferred tool for the capsulotomy is a radiofrequency (RF) cautery device (Easy Rhex, Loktal Medical Electronics), which is easy to use and has other important advantages. “With RF cautery, I can easily control the diameter and shape of the capsular opening and also enlarge it if I am not satisfied with the original size,” Dr Ventura said.

He also favours using RF cautery rather than the Utrata forceps or scissors to create the anterior capsulorhexis in eyes where there is significant fibrosis or calcification on the anterior capsule. “These areas of fibrosis or calcification are usually thick.Therefore, if attempting capsulorhexis using the Utrata forceps, there is an increased risk for causing a radial tear or zonular dehiscence,” Dr Ventura explained. “RF cautery cuts through these plaques effectively without causing zonular stress, and this technique does not compromise rhexis strength,” Dr Ventura said, adding that he has not encountered problems with radial tears or other signs of rhexis weakness during more than 10 years of using RF cautery. He added that if there is localised excessive fibrosis or calcification on one side of the anterior capsule that lies in the path of the planned capsulorhexis, it may be possibly avoided by slightly enlarging the capsular opening on that side. “However, when enlarging the anterior capsulorhexis in this situation, keep in mind that to avoid anteriorisation of the IOL, the haptics must be in the bag, and the border of the capsular opening should ideally overlap the lens optic rim by approximately 1.0mm around most of its circumference,” Dr Ventura said.

Insertion of an endocapsular tension ring (Visiontech Medical Optics) is also part of Dr Ventura’s routine in infantile cataract surgeries. Rare exceptions include eyes with extreme microphakia, those that will remain aphakic, or cases in which there are intraoperative complications such that the risk of ring insertion outweighs the benefit. By fully expanding and stabilising the capsular bag, the endocapsular tension ring enables implantation of Dr Ventura’s preferred IOL – a 12.5mm-long, 3-piece, foldable, hydrophobic acrylic IOL – and reduces capsular contraction to maintain a circular, central capsulorhexis and minimise IOL decentration. Dr Ventura plans primary IOL implantation in-the-bag in patients older than eight weeks of age, using an age-based algorithm that he developed for hypocorrecting IOL power in children up to four years old. He favours the 3-piece style implant because its haptics maintain bag expansion better than the haptics of a single-piece IOL, and it can still be placed through a small incision. If he anticipates the haptics of the 3-piece IOL cannot expand properly because the capsular bag is too small, Dr Ventura amputates part of both haptics and implants what remains into the capsular bag. “The haptics’ stubs will maintain IOL stability, particularly if the stubs penetrate into the capsule,” Dr Ventura said. To modulate postoperative inflammation, Dr Ventura injects 1.2 mg/0.03 mL of preservative-free triamcinolone acetonide (Triancinolona Ophthalmos, Laboratorio Ophthalmos) in the anterior chamber at the end of the case in patients younger than two years of age. After reforming the anterior chamber with a single air bubble, he injects the corticosteroid into the angle so that it occupies the 360° circumference of the space between the anterior chamber angle and the air bubble. Based on one-year follow-up results from 53 eyes of 34 patients operated on for congenital cataract when younger than two years of age, this use of triamcinolone does not appear to increase the risk of glaucoma or adversely
affect central corneal thickness [J AAPOS. 2012;16(5):441-4]. “For us, secondary opacification of the visual axis is no longer a frequent issue in infantile cataract surgery. I believe the development of this complication has been limited in

our hands by the combination of endocapsular tension ring placement, primary posterior capsulorhexis, anterior vitrectomy, and intracameral triamcinolone acetonide,” Dr
Ventura said. Finally, Dr Ventura closes the main and sideport incisions with 10-0 Vicryl. His choice of dissolvable suture material obviates any need to remove the stitches postoperatively – a procedure that would necessitate examination under anaesthesia.