A Mitomycin C-Sparing Novel Technique for Subscleral Trabeculectomy in Primary Congenital Glaucoma

Outcome measures in childhood glaucoma: a systematic review of randomized controlled trials

PURPOSE

To synthesize the outcome measures used by randomized controlled trials (RCTs) for childhood glaucoma.

METHODS

MEDLINE, EMBASE, and Scopus were searched from inception to February 17, 2023. Randomized controlled trials and observational studies related to childhood glaucoma were included. Primary and secondary outcomes were extracted and the data was used to generate a literature review.

RESULTS

This review identified 42 unique reports pertaining to childhood glaucomas. Most of the studies originated from Egypt, India, and the USA. Intraocular pressure (IOP) outcomes were the most frequent outcomes studied, followed by clinical outcomes and safety outcomes. Clinical outcomes were the most common secondary outcomes studied, followed by IOP outcomes and safety outcomes.

CONCLUSIONS

This systematic review found heterogenous outcomes with IOP outcomes as the most studied primary outcome. As the remaining outcomes were not consistently utilized, this review highlights the need for a consensus on studies of pediatric glaucoma.

Comparative efficacies of 13 surgical interventions for primary congenital glaucoma in children: a network meta-analysis of randomized clinical trials

BACKGROUND

Timely and proper intraocular pressure (IOP) management is vital to the prevention of visual impairment in children with primary congenital glaucoma (PCG). Although various surgical interventions have been proposed, no well-founded evidence exists on their comparative efficacies. We aimed to compare the efficacies of surgical interventions for PCG.

METHODS

We searched relevant sources up to 4 April 2022. Randomized controlled trials (RCTs) entailing surgical interventions for PCG in children were identified. A network meta-analysis (NMA) was performed, comparing 13 surgical interventions: Conventional partial trabeculotomy ([CPT] control), 240-degree trabeculotomy, Illuminated microcatheter-assisted circumferential trabeculotomy (IMCT), Viscocanalostomy, Visco-circumferential-suture-trabeculotomy, Goniotomy, Laser goniotomy, Kahook dual blade ab-interno trabeculectomy, Trabeculectomy with mitomycin C, Trabeculectomy with modified scleral bed, Deep sclerectomy, Combined trabeculectomy-trabeculotomy with mitomycin C, and Baerveldt implant. The main outcomes were mean IOP reduction and surgical success rate at postoperative 6 months. The mean differences (MDs) or odds ratios (ORs) were analyzed by a random-effects model, and the efficacies were ranked by P -score. We appraised the RCTs using the Cochrane risk-of-bias (ROB) tool (PROSPERO: CRD42022313954).

RESULTS

Sixteen RCTs were eligible for NMA, including 710 eyes of 485 participants and 13 surgical interventions, which formed a network of 14 nodes comprising both single interventions and intervention combinations. IMCT was superior to CPT in both IOP reduction [MD (95% CI): -3.10 (-5.50 to -0.69)] and surgical success rate [OR (95% CI): 4.38 (1.61-11.96)]. The MD and OR comparing the other surgical interventions and intervention combinations with CPT were not statistically significant. The P -scores ranked IMCT as the most efficacious surgical intervention in terms of success rate ( P -score =0.777). Overall, the trials had a low-to-moderate ROB.

CONCLUSION

This NMA indicated that IMCT is more effective than CPT and might be the most efficacious of the 13 surgical interventions for management of PCG.

Controversies in Pediatric Angle Surgery and Secondary Surgical Treatment

Pediatric glaucoma is a constellation of challenging ophthalmic conditions that, left untreated, can result in irreversible vision loss. The mainstay of treatment for primary congenital glaucoma and select secondary glaucoma subtypes is angle surgery, either trabeculotomy or goniotomy. More recently, MIGS devices have been utilized to enhance the efficacy of these procedures. Despite the high success rates of these primary surgical options, refractory cases are challenging to manage. There is no consensus on the next step of treatment following primary angle surgery. Glaucoma drainage devices and trabeculectomies have been the traditional options, with laser treatment reserved for more severe cases. The benefits and disadvantages of each of these options are discussed.

Histopathology, matrix metalloproteinase-2 and alpha smooth muscle actin expression in Tenon's capsule of eyes with congenital glaucoma

PURPOSE

To evaluate the ultrastructural features of collagen fibrils, matrix metalloproteinase (MMP) and alpha-smooth muscle actin (α-SMA) expression in the Tenon's capsule of buphthalmic eyes.

METHODS

A prospective comparative case series study was conducted on 35 buphthalmic eyes vs 25 control eyes. Children with congenital glaucoma (CG) who underwent a combined trabeculectomy-trabeculotomy procedure with mitomycin C (CTTM); the Tenon's capsule was obtained during the surgical procedure. The control group included children with strabismus, the Tenon's capsule was obtained in the course of strabismus surgery. Both H&E and Masson's trichrome staining were done. The Metalloprotenease-2 (MMP-2), alpha smooth muscle actin (α-SMA) immunohistochemical staining was performed.

RESULTS

Mean collagen percentage area by Masson trichrome stain in Tenons capsule was significantly higher in buphthalmic eyes (54.76% ± 0.32 vs 33.71% ± 1.4; P < 0.001).The percentage area of αSMA expression in Tenons capsule was significantly higher in buphthalmic eyes (4.93% ± 0.7 vs 2.00% ± 0.5; P < 0.001). However, MMP2 expression in Tenons capsule of the buphthalmic group was significantly lower than that of the control group (12.88% ± 2.95 vs 27.91% ± 0.2 respectively) P = 0.02.

CONCLUSIONS

Tenon capsule of buphthalmic eyes have their own histopathological features and properties making them more liable for fibrosis with high rate of failure following antiglaucoma surgeries. Such detailed information has not been published before which may aid in the identification of new antifibrotic therapies in management of glaucoma.