Long-term Results of Combined Trabeculotomy-Trabeculectomy in Primary Congenital Glaucoma from a Tertiary Eye Care Center in Tunisia

Abstract

ObjectiveTo report the long-term visual and surgical outcomes of combined trabeculotomy–trabeculectomy (CTT) as the initial glaucoma surgery in children with primary congenital glaucoma (PCG).MethodsProspective analysis of children who underwent primary CTT for PCG between January 2010 and December 2019. The main outcome measures were intraocular pressure (IOP) reduction, corneal clarity, success rate, complications, refractive errors and visual acuities (VA).ResultsA total of 98 eyes of 62 patients were enrolled. At last follow-up, mean IOP reduced from 22.68±3.99 mmHg to 9.75±3.88 mmHg (P<0.0001). Complete success rate was 91.6%, 88.4%, 84.7%, 71.6%, 59.7%, and 54.3%, respectively at first, second, fourth, sixth, eighth, and tenth year. Follow-up averaged 42.06±28.36 months. Preoperatively, 72 eyes (73.5%) had significant corneal haze, 84.7% among them achieved normal corneal transparency. Among the sight-threatening complications, endophthalmitis was encountered in one eye. Myopia was the most common refractive error (80.6%). Data on Snellen VA were available for 53.2% of the patients. 33.3% of patients achieved normal VA (VA ≥ 6/12), 21.2% had mild visual impairment (VI), 9.1% had moderate VI, 21.2% had severe VI, and 15.2% were blind. The failure rate was statistically correlated to the early disease onset (<3 months) and to preoperative corneal clouding (p=0.022 and p=0.037, respectively). Two critical time points were identified: within the first year and around the sixth year (28.6 and 25% of surgical failures, respectively).ConclusionPrimary CTT seems to be an optimal procedure in a population with advanced disease at presentation, problematic follow-ups, and limited resources.Summary boxWhat is already known on this topicPrimary congenital glaucoma (PCG) is the most common type of childhood glaucoma. Surgery is the main therapeutic option with the goal of permanently controlling IOP and preserving visual function. Several surgical procedures are available. Each approach has its potential benefits and risks. The optimum first-line surgery is debated.What this study adds?PCG in Tunisian children seems to be characterized by a high prevalence of inherited and advanced form of the disease.Challenges in the management of PCG in Tunisia include remoteness of care facilities and poor compliance to follow-up.Primary combined trabeculotomy-trabeculectomy allowed in the current study satisfactory long-term IOP control and reasonable visual outcome. The overall incidence of serious complications was low.How this study might affect research, practice or policyCTT may be the optimal primary surgical procedure for the management of PCG in Tunisia and all other developing countries. Future research with a larger sample size and preferably randomized clinical trials that focus exclusively on the severe presentation of the disease are required.