Insertion of sequential glaucoma drainage implant in a piggyback manner

Abstract

Purpose This pilot study, the first of its type, was conducted to determine the clinical outcome of a sequential glaucoma drainage implant (GDI) inserted in piggyback manner, that is into the bleb of a primary GDI. Methods This was a retrospective chart study with a minimum 1-year follow-up involving 16 eyes of 14 uncontrolled glaucoma patients who had previously undergone sequential GDI performed using a technique to convert a one-plate into a two-plate implant system. Surgical success was defined as intraocular pressure (IOP) o21 mm Hg with at least a 30% reduction in IOP from baseline on two consecutive follow-up visits, IOP 45 mm Hg on two consecutive follow-up visits, and neither reoperation of glaucoma nor loss of light perception vision. Results The mean ± SD baseline IOP was 29.2 ± 5.2 mm Hg, and the mean postoperative IOP was 17.3 ± 3.4 mm Hg, with a mean pressure drop of 39.4 ± 10.4% (Po0.001). Life-table analysis showed an 88% success rate after 12 months of follow-up. The mean preoperative best corrected visual acuity (BCVA) was 0.2 ± 0.2 logMAR (Snellen equivalent 6/9.5), compared with 0.3 ± 0.3 logMAR postoperatively (Snellen equivalent 6/12; P = 0.497). Postoperative complications included a flat anterior chamber and choroidal detachment (one eye), uveitis and cataract (one eye), diplopia (one eye), and worsening of pre-existing pseudophakic bullous keratopathy (one eye). Conclusions In glaucoma eyes with useful vision the piggyback GDI seems to provide a significant IOP lowering with minimal complications in patients in whom an initial GDI had failed to control the IOP.

Intermediate‐term and long‐term outcome of piggyback drainage: connecting glaucoma drainage device to a device in‐situ for improved intraocular pressure control

“…The first was likely precipitated by placement of the piggyback GDD and in the second eye was probably largely due to a pre‐existing traumatic ocular injury. The corneal decompensation rate in the recently published piggyback paper was 8.3% over a shorter time period . Rates of corneal decompensation following second GDD into the anterior chamber appear significantly higher.…”

“…A retrospective consecutive case series of 16 eyes undergoing a piggyback secondary GDD with 1‐year follow‐up was recently reported . The patients had similar heterogeneity of primary diagnosis and primary tubes.…”

“…12 A retrospective consecutive case series of 16 eyes undergoing a piggyback secondary GDD with 1-year follow-up was recently reported. 14 primary tubes. They used the Molteno 3 tube for their secondary GDD, whereas we used both the Molteno 3 and Baerveldt tube.…”

“…This involves connecting a new GDD to a pre‐existing GDD, avoiding the need for a new tube being passed into the anterior chamber termed ‘piggyback drainage’. A recently published retrospective case series with a mean follow‐up of 17 months using this technique indicates that it provides significant additional IOP lowering where a primary GDD fails . The aim of this retrospective interventional study was to evaluate the intermediate‐term and long‐term efficacy and safety of this procedure in eyes that have failed a primary GDD.…”

Recent Advancements in Glaucoma Surgery—A Review

“…No cases of diplopia or corneal decompensation were observed. In 16 eyes of 14 patients with uncontrolled glaucoma, Valimaki et al [ 46 ] inserted a second glaucoma drainage implant in a piggyback manner. The sequential implant was rotated so that the tube of the ‘piggyback’ implant was directed towards the quadrant containing the original implant and inserted into the bleb, thereby converting a one-plate into a two-plate implant.…”