Baerveldt glaucoma implant in paediatric patients

Abstract

Aim: To evaluate the Baerveldt glaucoma implant (BGI) in paediatric glaucoma treatment. Methods: In a retrospective non-comparative case series 55 eyes of 40 consecutive paediatric patients ((16 years) with primary or secondary glaucoma underwent Baerveldt (350 mm 2 ) implantation. Surgical outcome was evaluated by Kaplan-Meier table analysis. Results: The overall success rate was 80% at last follow up, with a mean follow up of 32 (range 2-78) months. Cumulative success was 94% at 12 months and 24 months, 85% at 36 months, 78% at 48 months, and 44% at 60 months. 11 eyes (20%) failed postoperatively because of an IOP .21 mm Hg (eight eyes), persistent hypotony (two eyes), and choroidal haemorrhage following cataract surgery (one eye). The most frequent complication needing surgery was tube related (20%). A new observation was mild to moderate dyscoria in 22% of the eyes, all buphthalmic, caused by entrapment of a tuft of peripheral iris in the tube track. Conclusions: The BGI is effective and safe in the management of primary and secondary glaucoma. When angle surgery has proved to be unsuccessful or inappropriate in paediatric patients, a BGI is a good treatment option. One must be prepared to deal with the tube related problems.

The Role of Glaucoma Drainage Devices in Paediatric Glaucoma

“…The global rate of complications reached as high as 84.6 % in the series by Chen et al 12 (44/52 eyes) and they do occur with any type of GDD, such as the Ahmed valve, with complications arising in 28.9 % of the cases in the series by Albis et al, 11 and in 17.6 % in the series by Yang et al, 17 or with the Baerveldt implant, with complications in 18.7 % of the cases in the series by Rolim de Moura et al 6 Besides their frequency, complications in children are even more important because many of them, at this age, must be resolved under general anaesthesia, leading to a high reported rate of additional interventions, 48.1 % in the series by Chen et al 12 and 30.9 % in that by Overdam et al 21 Post-operative tube migration (typically anteriorly) is the most common complication in the vast majority of series, with figures as high as 34.8 % in the series by Beck et al 4 and 26.2 % in the series by Al Mobarak et al 13 Tube migration can occur more frequently in younger patients and buphthalmic eyes. 3 Anterior displacement of the tube may be related to the higher relative rigidity of the tube compared to the elasticity of the sclera in children, which may result in a tendency of the tube to slowly straighten and rotate anteriorly towards the cornea, particularly if the tube has been forced Glaucoma…”

“…Early post-operative success may be as high as 90 %, 11,21 but it decreases over time, to 40-60 % survival at 4-6 years using the Kaplan-Meier analysis. 8,11,12 In our experience, survival using the Kaplan-Meier analysis has been 76 % at 6 months, 63 % at 1-3 years and 55 % at 4-8 years.…”

“…5,6,8,12,14,17,21 Apart from the well-known factors involved in its development in adults, such as poor lubrication of the ocular surface, micro-movements of the tube, rubbing against the tarsal plate and previous use of MMC, in children its occurrence is even more likely to be produced by eye rubbing, which is hardly avoidable (see Figure 3). Children younger than two at the time of surgery appear to be at higher risk for this complication.…”

“…Kirwan et al 19 21 This complication can be secondary to a mass effect from the bleb or the implant itself, or to muscle dysfunction due to direct damage, inclusion in the capsule, posterior fixation (faden effect) due to scarring under the recti, or fat adhesion syndrome. These disorders are more common after placement in the superonasal or inferonasal quadrant.…”

Childhood glaucoma surgery in the 21st Century

“…At 1-2 year follow-up, many studies report a success of around 80% [85][86][87][88] and this falls to around 50% in the longer term. 72,[89][90][91][92] When debating which GDD performs best in children-there is no clear superiority of one type of GDD versus another, however the Baerveldt implant may provide slightly better long-term IOP control but the Ahmed implant fewer short term complications. [93][94][95] A prospective study comparing the polypropylene against the silicone Ahmed implant in children, has shown better long-term IOP control with the silicone Ahmed.…”