Frontalis Suspension Before Age 2 Can Limit Amblyopia

Frontalis suspension surgery for congenital ptosis is typically performed after children reach the age of 3, in part to allow ocular muscle development, but an analysis conducted by researchers at Hunan Children’s Hospital, in China indicates there may be less damage to acuity and binocular vision for those who receive the procedure at less than 2 years of age, according to data published in BMC Ophthalmology.

Ptosis was suspected to create enough pressure to produce astigmatism affecting visual processing, so this study evaluated whether an earlier frontalis suspension surgery with polytetrafluoroethylene (PTFE) could avoid amblyopia caused by combined impacts of astigmatism and blocked sightline. Investigators recruited 53 patients with unilateral congenital ptosis, ranging in age from 8 to 23 months. Children presented a drooping eyelid covering half or more of the pupil.

Postoperative examinations took place after 1 month, 6 months, and 12 months. Complete 1-year data was available for 39 individuals. “The results of refraction follow-up suggested that, to a certain extent, the surgery could reduce visual damage and amblyopia incidence rate caused by severe ptosis during the critical period of visual development,” according to the researchers. 

In this cohort, 51.3% of eyes with ptosis exhibited preoperative astigmatism worse than -1.50 diopters (D), with a group mean of -1.45±0.59 D, compared with severe astigmatism in 12.8% of fellow eyes and group average of -0.66±0.51 D (P <.001). Further, 59% of case eyes displayed against-the-rule (AR) astigmatism and 10.2% oblique astigmatism (OA), compared with 20.5% of fellow eyes exhibiting AR and 0% OA.

After frontalis suspension surgery, the 39 eyes with full data showed a small increase in astigmatism after 1 month — possibly due to swelling — but then lessened at 6 months, followed by significant improvement from baseline at 1 year (P <.001). One month post-surgery, only 35.9% of ptosis-affected eyes displayed AR and 7.7% OA. Also, many case eyes’ astigmatism evolved to with-the-rule astigmatism (WR) by follow-up examinations; a 30.8% rate before surgery changed to 56.4% at 1 month.

At 1 year, 33 children showed suitable lid position. At 30 months, 10 patients retained eyelid height. Overall, Kaplan-Meier survival analysis revealed an 81.4% success rate at 6 months, 62.9% after 1 year, 33.3% at 18 months, and 18.5% after 30 months. Recurrence was the most frequent long-term complication. Eight individuals experienced short-term mild effects such as infection, suture reaction, epithelial keratopathy, and granuloma formation, but these were swiftly treated and refraction unaffected.

Previous research on frontalis suspension surgical treatment has yielded a higher success rate than the current investigation, which may be due to factors such as suture-related concerns — or ametropia of the case eye not resolving soon enough, provoking a recurrence. Also, younger participants and more severe condition may have prompted relapse.

Limitations of this study included lack of refractive data for some individuals, a somewhat short follow-up duration, as well as infants and toddlers not being able to complete tests such as corneal topography. The investigators suggest children with stable outcome after 1 year may experience an easier transition to further surgeries after age 3.