Fig. 8.55 Graph of the mean number of medication to lower intraocular pressure at each visit after combined phacoemulsiÞcation and iStent¨ procedure

Time (Months)

n = 2; repositioning, n = 1). All eyes achieved a signiÞcant reduction in IOP and 6 also discontinued glaucoma medications. Of the 7 patients with stent lumen obstruction, 3 underwent treatment (rTPA injection, n = 2; gonioplasty, n = 1). The remaining 4 achieved a signiÞcant reduction in IOP and discontinued glaucoma medications. None of the device-related adverse events were considered serious.

8.4.5.3Phacoemulsification Cataract Surgery Combined with Implantation of Two Trabecular Implants

This is the most recent study carried out with the iStent. A multicenter, prospective study was designed, in which the patients were randomly divided into two groups. The patients in the Þrst group had conventional cataract surgery, while the patients in the second group had cataract surgery combined with two trabecular stents [11].

No signiÞcant intraoperative complications were recorded in either group. Up to this time, only partial results were available, with a follow-up of 1 year. Starting with similar baseline pressures in both groups (p = 0.2), the decrease obtained was signiÞcantly higher in the group with combined surgery at all the follow-up points during the postoperative period. After 12 months of follow-up, the decrease in the group with combined surgery was 6.57 (±2.95) mmHg compared to 3.86 (±2.68) mmHg in the group that had cataract surgery (p = 0.002) [mean (±SD)]. The need for antiglaucoma treatment was also lower in the combined surgery group at the end of the fol- low-up (p = 0.007).

The most frequent complication was once again the malpositioning of the stent, although in all cases in which one of the stents was found to be malpositioned, the other stent was placed correctly. This fact could

explain, at least in part, the greater efÞcacy of the surgery when two stents are implanted. In one subgroup of patients in this study, the outßow facility of the aqueous humor was measured by ßuorophotometry [11]. After surgery, there was a signiÞcant increase in outßow facility in both groups. This increase was signiÞcantly greater in the group with combined surgery after the 6-month follow-up. One year after surgery, the increase in outßow facility with respect to the baseline values was 275% in the group with combined surgery and 46% in the group with isolated cataract surgery.

8.4.6 Conclusions

The various studies have conÞrmed the use of the trabecular stent as an additional option in glaucoma surgery. Supported by the absence of complications, its hypotensive effectiveness can be sufÞcient in nonadvanced cases of glaucoma that require a moderate decrease in IOP or a decrease in the requirements for topical hypotensive medication. It is a suitable option in cases of combined surgery, having demonstrated a signiÞcant additional effect on the IOP and an increase in the long-term outßow facility of the aqueous humor. It has the additional advantage of not compromising the effectiveness of future Þltering surgery in the event of poor control of the disease.

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