Recent medical and surgical therapeutic advances have improved our ability to manage pediatric glaucoma, a potentially blinding condition characterized by elevated IOP, optic nerve damage and visual field loss. However, challenges still remain in treating this heterogeneous group of diseases. We discuss these advances and optimal treatment for pediatric glaucoma.
Pediatric glaucoma can be categorized as primary when a patient has an isolated developmental abnormality of the anterior chamber angle and secondary when aqueous humor outflow is reduced by either a congenital or acquired ocular or systemic disorder.1
In pediatric glaucoma, medications often play a supportive role, temporarily reducing IOP prior to surgical intervention. Long-term medical therapy can be used in secondary glaucomas or more severe disease not controlled with surgery. If the risks of using a particular medication appear to outweigh the benefits in a particular patient, the clinician should use the smallest effective dose possible and monitor the patient closely for adverse effects.2
Beta blockers have been used successfully in patients with various types of pediatric glaucoma.3 A recent prospective trial showed statistically significant reductions in IOP with betaxolol (0.25%) or timolol (0.25% or 0.5%) in pediatric glaucoma patients under six years of age. All formulations were well tolerated and produced no serious adverse events.4
Oral carbonic anhydrase inhibitors effectively reduce IOP in children and can be used in divided doses to reduce corneal edema prior to surgery. Topical brinzolamide produces clinically relevant IOP reductions. One study found it to be well tolerated in untreated glaucoma patients under six years of age who were followed for three months.5
Latanoprost, a prostaglandin analog, has been used safely in a variety of pediatric glaucomas, including patients with Sturge-Weber syndrome.6 While most children respond poorly to latanoprost, some experience a significant reduction in IOP, particularly those with juvenile open-angle glaucoma.7 Latanoprost is safe and well-tolerated in children over the long-term.8
Brimonidine, an alpha-2 agonist, can cause significant central nervous system depression (including somnolence, hypotension or bradypnea) in young pediatric patients.9 It should be avoided in infants and toddlers and used cautiously in older children.10
Angle surgery (goniotomy ab interno or trabeculotomy ab externo) has traditionally been the surgical procedure of choice for the treatment of primary congenital glaucoma (PCG). Standard filtration surgery is an option for some types of secondary glaucoma or in eyes with a failed angle procedure, while glaucoma drainage devices (GDDs) are useful in cases refractory to conventional angle or filtration surgery, or when other surgical procedures are likely to fail.
Recent studies have compared the outcomes of trabeculectomy with MMC versus GDD implantation. One study reported significantly higher rates of success with GDD implantation (53 vs. 19 percent) after six years of follow-up.11 However, another group reported similar rates of success with either procedure.12
Cyclodestructive procedures used to treat pediatric glaucoma include cyclocryotherapy, transscleral cyclophotocoagulation (Nd:YAG, diode or krypton laser) and, more recently, endoscopic cyclophotocoagulation. Because of the frequent need for retreatment and the risk of irreversible complications, such as phthisis bulbi, most clinicians reserve cyclodestructive therapy for eyes in which conventional surgical approaches have failed.
Goniotomy involves the insertion of a knife or needle across the anterior chamber under direct visualization of a Swan-Jacob goniotomy lens. An incision is then made in the trabecular meshwork over about 120 degrees. A clear cornea is essential for optimal viewing of the angle structures.
Success rates for goniotomy range from 70 to 90 percent in eyes after birth and before age two.13,14 Retreatment is necessary in 25 to 30 percent of cases.15 Success rates are much lower for eyes presenting with PCG at birth or after 24 months of age.13,14 Recently, endoscopic goniotomy has been described for use in eyes with opaque corneas.16
Alternatively, trabeculotomy ab externo can be performed for the treatment of PCG and childhood glaucomas, especially when corneal clouding prevents an adequate gonioscopic view.17 This procedure requires an external dissection of Schlemm's canal, which is then cannulated with a metal probe or trabectome. The trabectome is then rotated into the anterior chamber, disrupting the trabecular meshwork.
Some authors have reported higher success rates with trabeculotomy than goniotomy,18 while others have reported similar outcomes.19,20 Recently, a technique using a 6-0 polypropylene (Prolene) suture to treat 360 degrees of the angle from one incision site was described, with a reported success rate exceeding 90 percent in eyes with PCG.21
Success rates for trabeculectomy in children generally are lower than those reported for adults, ranging from 35 to 50 percent after one year.22,23 The procedure has a particularly low success rate when performed in children younger than 12 months compared with older children (30 vs. 73 percent).24 The use of intraoperative antimetabolites, such as mitomycin C (MMC), may improve the chances of a successful filtration bleb25 but also increase the risk of postoperative complications, such as endophthalmitis.26
Combined trabeculotomy-trabeculectomy can be used as a primary procedure in eyes with a poor prognosis for angle surgery alone. One study reported a success rate of 63 percent with combined trabeculotomy-trabeculectomy after eight years of follow-up.27
Glaucoma drainage devices
Reported success rates for GDDs range from 54 to 95 percent, depending on the criteria used for success and length of follow-up.28-30 One study on the use of GDDs in eyes with congenital and aphakic glaucoma reported one-year Kaplan-Meier success rates of 92 and 90 percent, respectively. However, these rates fell to 42 and 55 percent, respectively, by 10 years.31
Postoperatively, patients often require adjunctive medications for IOP control. Re-operation is required in about 25 percent of patients.31 Reported complications include hypotony with shallow anterior chamber, choroidal effusions, tube blockage, tube exposure, endophthalmitis and retinal detachment. Tube-cornea touch is particularly common among younger children and often requires surgical repositioning to prevent corneal edema.32 Ocular motility disturbances and strabismus may also occur following GDD implantation and should be considered preoperatively, especially in children with binocularity.33
Reported success rates for cyclocryotherapy range from 18 to 44 percent.34 While cryotherapy is often effective at reducing IOP in cases of refractory glaucoma, the risk of phthisis bulbi following the procedure is 12 percent.35
In recent years, laser-based techniques have largely replaced cryotherapy for ciliary body destruction.36 One study using transscleral diode laser reported a success rate of 50 percent at six months, including patients who were retreated; 70 percent of patients underwent retreatment at least once.36 Similar success rates have been reported with contact transscleral Nd:YAG laser cyclophotocoagulation.37
Early reports of endoscopic cyclophotocoagulation show similar rates of success with less need for retreatment.38 However, the potential for inducing chronic intraocular inflammation and aqueous hyposecretion should be considered before undertaking any type of cyclodestructive procedure.
Multifaceted approach often required
Eyes with pediatric glaucoma often require a combination of medications and surgery for optimal IOP control. Further studies are needed to determine the most effective and safest way to treat this uncommon, but often devastating, disease.
- Papadopoulos M, Khaw PT. Childhood Glaucoma. In: Taylor D, Hoyt CS, eds. Pediatric Ophthalmology and Strabismus. 3rd ed. Philadelphia, Pa.: Elsevier Saunders; 2005:458-471.
- Wallace DK, Steinkuller PG. Ocular medications in children. Clin Pediatr. 1998;37(11):645-652.
- Boger WP 3rd, Walton DS. Timolol in uncontrolled childhood glaucomas. Ophthalmology. 1981;88(3):253-258.
- Plager DA, Whitson JT, Netland PA, et al. Betaxolol hydrochloride ophthalmic suspension 0.25% and timolol gel-forming solution 0.25% and 0.5% in pediatric glaucoma: a randomized clinical trial. J AAPOS. 2009;13(4):384-390.
- Whitson JT, Roarty JD, Vijaya, L, et al. Efficacy of brinzolamide and levobetaxolol in pediatric glaucomas: a randomized clinical trial. J AAPOS. 2008;12(3):239-246.e3.
- Yang CB, Freedman SF, Myers JS, Buckley EG, Herndon LW, Allingham RR. Use of latanoprost in the treatment of glaucoma associated with Sturge-Weber syndrome. Am J Ophthalmol. 1998;126(4):600-602.
- Enyedi LB, Freedman SF, Buckley EG. The effectiveness of latanoprost for the treatment of pediatric glaucoma. J AAPOS. 1999;3(1):33-39.
- Black AC, Jones S, Yanovitch TL, Enyedi LB, Stinnett SS, Freedman SF. Latanoprost in pediatric glaucoma - pediatric exposure over a decade. J AAPOS. 2009;13(6):558-562.
- Enyedi LB, Freedman SF. Safety and efficacy of brimonidine in children with glaucoma. J AAPOS. 2001;5(5):281-284.
- Bowman RJC, Cope J, Nischal KK. Ocular and systemic side effects of brimonidine 0.2% (Alphagan) in children. Eye. 2004;18(1):24-26.
- Broughton WL, Parks MM. An analysis of treatment of congenital glaucoma by goniotomy. Am J Ophthalmol. 1981;91(5):566-572.
- Beck AD, Freedman S, Kammer J, Jin J. Aqueous shunt devices compared with trabeculectomy with mitomycin-C for children in the first two years of life. Am J Ophthalmol. 2003; 136(6):994-1000.
- Hill R, Ohanesian R, Voskanyan L, Malayan A. The Armenian Eye Care Project: surgical outcomes of complicated paediatric glaucoma. Br J Ophthalmol. 2003;87(6):673-676.
- Russell-Eggitt IM, Rice NSC, Jay B, Wyse RK. Relapse following goniotomy for congenital glaucoma due to trabecular dysgenesis. Eye. 1992;6(Pt 2):197-200.
- Taylor RH, Ainsworth JR, Evans AR, Levin AV. The epidemiology of pediatric glaucoma: the Toronto experience. J AAPOS. 1999;3(5):308-315.
- Bayraktar S, Koseoglu T. Endoscopic goniotomy with anterior chamber maintainer: surgical technique and one year results. Ophthalmic Surg Lasers. 2001;32(6):496-502.
- Smith R. A new technique for opening the canal of Schlemm. Preliminary report. Br J Ophthalmol. 1960;44:370-373.
- McPherson SD Jr, Berry DP. Goniotomy vs. external trabeculotomy for developmental glaucoma. Am J Ophthalmol. 1983;95(4):427-431.
- Anderson DR. Trabeculotomy compared to goniotomy of glaucoma in children. Ophthalmology. 1983;90(7):805-806.
- Hoskins HD, Shaffer RN, Hetherington J. Goniotomy vs. trabeculotomy. J Pediatr Ophthalmol Strabismus. 1984;21(4):153-158.
- Beck AD, Lynch MG. 360 degrees trabeculotomy for primary congenital glaucoma. Arch Ophthalmol. 1995;113(9):1200-1202.
- Fulcher T, Chan J, Lanigan B, Bowell R, O'Keefe M. Long-term follow up of primary trabeculectomy for infantile glaucoma. Br J Ophthalmol. 1996;80(6):499-502.
- Sturmer J, Broadway DC, Hitchings RA. Young patient trabeculectomy. Assessment of risk factors for failure. Ophthalmology. 1993;100(6):928-939.
- Freedman SF, McCormick K, Cox TA. Mitomycin C-augmented trabeculectomy with postoperative wound modulation in pediatric glaucoma. J AAPOS. 1999;3(2):117-124.
- Azuara-Blanco A, Wilson RP, Spaeth GL, Schmidt CM, Augsburger JJ. Filtration procedures supplemented with mitomycin C in the management of childhood glaucoma. Br J Ophthalmol. 1999;83(2):151-156.
- Beck AD, Wilson WR, Lynch MG, Lynn MJ, Noe R. Trabeculectomy with adjunctive mitomycin C in pediatric glaucoma. Am J Ophthalmol. 1998;126(5):648-657.
- Mandal AK, Bhatia PG, Bhaskar A, Nutheti R. Long-term surgical and visual outcomes in Indian children with developmental glaucoma operated on within 6 months of birth. Ophthalmology. 2004;111(2):283-290.
- Nesher R, Sherwood MB, Kass MA, Hines JL, Kolker AE. Molteno implants in children. J Glaucoma. 1992;1(4):228-232.
- Fellenbaum PS, Sidoti PA, Heuer DK, Minckler DS, Baerveldt G, Lee PP. Experience with the Baerveldt implant in young patients with complicated glaucomas. J Glaucoma. 1995;4(2):91-97.
- Englert JA, Freedman SF, Cox TA. The Ahmed valve in refractory pediatric glaucoma. Am J Ophthalmol. 1999;127(1):34-42.
- Schotthoefer EO, Yanovitch TL, Freedman SF. Aqueous drainage device surgery in refractory pediatric glaucomas: I. Long-term outcomes. J AAPOS. 2008;12(1):33-39.
- Morad Y, Donaldson CE, Kim YM, Abdolell M, Levin AV. The Ahmed drainage implant in the treatment of pediatric glaucoma. Am J Ophthalmol. 2003:135(6):821-829.
- Schotthoefer EO, Yanovitch TL, Freedman SF. Aqueous drainage device surgery in refractory pediatric glaucomas: II. Ocular motility consequences. J AAPOS. 2008;12(1):40-45.
- al Faran MF, Tomey KF, al Mutlaq FA. Cyclocryotherapy in selected cases of congenital glaucoma. Ophthalmic Surg. 1990;21(11):794-798.
- Shields MB. Cyclodestructive surgery for glaucoma: past, present, and future. Trans Am Ophthalmol Soc. 1985;83:285-303.
- Bock CJ, Freedman SF, Buckley EG, Shields MB. Transscleral diode laser cyclophotocoagulation for refractory pediatric glaucomas. J Pediatr Ophthalmol Strabismus. 1997;34(4):235-239.
- Phelan MJ, Higginbotham EJ. Contact transscleral Nd:YAG laser cyclophotocoagulation for the treatment of refractory pediatric glaucoma. Ophthalmic Surg Lasers. 1995;26(5):401-403.
- Neely DE, Plager DA. Endocyclophotocoagulation for management of difficult pediatric glaucomas. J AAPOS. 2001;5(4):221-229.