© 2021 MJH The Age of Life Sciences and Ophthalmology. all rights reserved.

© 2021 MJH Life Sciences™ and Ophthalmology Times. all rights reserved.

Cataract surgery in young patients can be a challenge, and evolving technology can be used for cataract surgery in young children.

Cataract surgery for very young children can be challenging, partly because the anatomical features of the eye may be only a few weeks old, but mainly because the initial surgery is usually only the first of the many interventions that may be required next. In the next few years, patients have the opportunity to develop normal and healthy vision. Femtosecond lasers can play a key role in achieving this goal.

We are one of the first centers to use femtosecond lasers in pediatric cataract cases, which, like many interventions for our youngest patients, is an off-label procedure or contraindication for most laser platforms (the Ziemer laser system is an exception because it There is a CE mark for laser cataract surgery for pediatric cases).

Before planning an intervention, the surgeon must understand some of the issues in pediatric cataract surgery. There will be soft eye tissues with low scleral stiffness, and surgery—usually preoperative and postoperative inspections—must be performed under general anesthesia.

Calculating the appropriate intraocular lens power can be very difficult (if you plan to implant an intraocular lens). An automatic keratometer will be necessary. Another consideration is that posterior capsule opacification (PCO) may occur within a relatively short period of time after surgery. If the posterior capsule is intact, this complication will almost certainly occur. Finally, the surgeon must be able to perform vitrectomy.

Choosing the best time to perform surgery on newborns or very young children always means weighing the risks and benefits. After early surgery, a large amount of axial elongation and a large amount of myopia displacement can be expected.

Surgery at a very young age increases the likelihood of major complications after glaucoma surgery. When the patient is under 4 weeks of surgery, the incidence of this and other postoperative complications is much higher.

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The general recommendation may be—but caution—surgery for unilateral congenital cataracts should be performed 4 to 6 weeks after birth, and surgery for bilateral cataracts should be performed 6 to 10 weeks after birth. 1,2

We have used femtosecond lasers for pediatric cataract surgery for nearly 10 years, and our experience is generally very positive. 3 Unlike adult cataract surgery, we do not use laser for lens fragmentation (this is done by suction), but it is mainly used to achieve a perfect capsulotomy-anterior and posterior-which is essential, Not only when planning to perform the first intraocular lens implantation.

Since anterior capsulotomy is a key step in surgery and postoperative vision recovery, when we found the best roundness of anterior and posterior capsulotomy created by femtosecond laser, we even gave our first pediatric laser The cataract surgery case is satisfied. 4 As expected, due to elasticity, the size of the capsulotomy did not initially proceed as planned. After the laser treatment, the opening of the capsule was immediately enlarged significantly.

Based on experience, we have found that, especially in very young children, the diameter of capsulotomy is often larger than planned. In a clinical series involving 22 eyes of 18 patients, we were able to develop the Bochum formula to correct this aberration. 5

Use the following formula to obtain the required capsulotomy diameter:

The real bane of pediatric cataract surgery is the high incidence of PCO. A special surgical technique-more suitable for experienced surgeons rather than novices-may greatly reduce the chance of this complication developing.

Marie-José Tassignon, MD, first described in 2002, in the bag-of-lens (BIL) technique, after the femtosecond laser is used for anterior and posterior capsulotomy, the anterior and posterior capsules are placed in a special intraocular lens method Lanzhong. Laser is especially important for creating a perfectly centered posterior capsulotomy.

The intraocular lens used is a foldable hydrophilic monolithic intraocular lens, which is fully inserted and unfolded in the anterior chamber. The rear tactile element is placed behind the posterior capsule, and the front tactile element is located in front of the front capsule. This prevents long-term proliferation and migration of lens epithelial cells, thereby preventing PCO.

For surgeons who have not previously implanted a BIL lens, the femtosecond laser may make this challenging manual technique an option. Femtosecond laser can safely perform posterior capsulotomy and keep the anterior transparent membrane intact. 6

For patients with special needs, there are additional preoperative considerations. For example, children with Down syndrome have a higher incidence of cataracts in children than the general population.

However, as Saifee et al.7 pointed out based on their experience, the incidence of complications from cataract surgery in pediatric patients with Down syndrome does not seem to be higher than that of cataract surgery in the general pediatric population. There is no reason to believe that laser cataract surgery on these patients may not be as effective or safe as children without this condition. 7

People with Marfan syndrome may need lens surgery even if they do not have cataracts. Their vision is often affected by subluxation of the lens. Irregular astigmatism at the edge of the lens and occasional lens opacity can lead to aphakia.

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The removal of the lens through capsule fixation and intraocular lens implantation is an important strategy to solve these problems. However, like young patients with congenital cataracts, the challenge of manual capsulorhexis comes from the high elasticity of the capsule (there is a tendency to tear backwards), the damage to the zonules caused by pressure during the operation, and the fact that capsulorhexis is required. It is off-center, which often leads to an increase in intraoperative complications for these patients who underwent surgery at a relatively young age.

In the first batch of cases treated with femtosecond laser, we performed surgery on a 10-year-old boy with ectopic lenses in both eyes, using femtosecond laser on his right eye under general anesthesia. After using the integrated algorithm to identify the ocular surface, the software automatically places the capsulotomy in the center of the scanning capsule, which is located on the upper temporal side of the pupil.

The selected capsular incision diameter is 4.1 mm (incision depth: 1000 μm). No lens fragmentation was performed. The total suction time is 2 minutes and 45 seconds. Using micro tweezers to remove the capsule disk, no radial tear was found. Aspirate the soft lens with a standard two-hand rinsing/suction device.

No complications were observed during the 10 weeks of follow-up. 8 Given that most pediatric laser cataract surgeries on laser platforms are not compliant, there are still some shortcomings that are expected to be overcome in the near future.

There is no software suitable for posterior capsulotomy, so the treatment area must be manually positioned. Only 2 laser platforms (Johnson + Johnson Vision and Ziemer) have interfaces for smaller eyes. There is no special formula for choosing the right intraocular lens for our youngest patient: all intraocular lenses are designed for adults.

Experience has shown that Barrett’s formula is more reliable than other formulas. It is worth noting that the ideal target diopter for very young babies seems to be mild myopia, because they are mainly concerned with nearby objects, such as their toys or mother's face. 9

Surgery is the first step in the restoration of vision in children with cataracts, followed by long-term care provided by ophthalmologists. Parents (or caregivers) must be educated about the necessity of continuous follow-up, so that when complications such as inflammation, glaucoma, and PCO occur, they can be detected and treated in time, corrected refractive errors, and treated for amblyopia. pursued.

For the first step, we should use all our expertise and the best technology available. In my opinion, this is usually a femtosecond laser.

H. Burkhard Dick, MD, PhD, FEBOS-CR

Email: Burkhard.Dick@kk-bochum.de

Dick is a professor and chairman of the Ophthalmology Clinic at the Ruhr University in Bochum, Germany. He is an on-demand consultant for Johnson + Johnson.