8.4.4Postoperative Management and Medication

Postoperative treatment should include a topical antibiotic during the Þrst week and topical corticosteroids for 4 weeks. These corticosteroids should be tapered after a few weeks to prevent steroid-induced ocular hypertension. They should be followed by nonsteroidal inßammatory drugs, three times a day, for at least 3 months after surgery.

8.4.5Outcomes and Combination with Other Techniques

Experience with the trabecular stent is limited, although the results are encouraging, both from the point of view of the hypotensive effectiveness and with regard to the safety of the procedure and the biocompatibility of the device. The results are essentially from three clinical trials carried out over recent years, involving different groups of patients. The most relevant information from these three studies is as follows:

a.Implantation of the trabecular stent in refractory glaucoma patients

b.PhacoemulsiÞcation surgery combined with implantation of a trabecular stent [6]

c.Comparative study of isolated cataract surgery vs. combination cataract surgery with two trabecular implants. In one subgroup of patients in this study, ßuorophotometry was used to analyze the increase

in ease of passage of the aqueous humor caused by the implantation of the trabecular stents

8.4.5.1Trabecular Implant in Refractory Glaucoma Patients

For the Þrst study of the trabecular stent in humans, patients were selected with pressures above 21 mmHg, maximum toleration of medical treatment and at least one failed conventional Þltering operation [10].

A prospective, multicenter study was designed that included 45 patients. The 12-month results are currently available; however, the study runs over 24 months. The principal objective of the study was to evaluate the effect of the implantation of the trabecular stent on IOP. All the hypotensive medications were discontinued after the surgery and reintroduced at the discretion of the investigator.

The average age of the study patients was 64.9 (±11) years [mean (±SD)]. All patients had primary openangle glaucoma; 16 and 2% were also diagnosed with pseudoexfoliative and pigmentary glaucoma, respectively. The average baseline pressure was 28.8 (±6.28) mmHg, with patients using an average of 2.1 topical hypotensive medications. At 12 months postoperatively, the mean IOP for all treated eyes had decreased to 19.3 (±5.1) mmHg (n = 28) and for patients without (or before) secondary surgical intervention had decreased to 18.8 (±4.7) mmHg (n = 24), without diminution of effect over time (Fig. 8.52). For all treated eyes, the mean decrease from the medicated baseline IOP ranged from 4.9 to 11.0 mmHg and for patients without (or before) intervention the mean decrease ranged from 5.2 to 12.2 mmHg. At 12-month, for all eyes (n = 28), the mean decrease in the number of medications compared

Fig. 8.52 Graph of the mean intraocular pressure measurement at each visit after implantation in refractory glaucoma patients

Fig. 8.53 Graph of the mean number of medication to lower intraocular pressure at each visit after implantation in refractory glaucoma patients

medicationsof Number PreOP

Time (Months)

Fig. 8.54 Graph of the mean intraocular pressure measurement at each visit after combined phacoemulsiÞcation and iStent¨ procedure

with baseline was 1.4 (±1.1) and for the patients without intervention (n = 24) was 1.0 (±1.2) (Fig. 8.53).

No signiÞcant intraoperative complications were recorded. The most common postoperative complication was malpositioning of the stent (3/45, 6.6%), which required replacement in two cases. One case presented above-average bleeding in the anterior chamber, which did not require additional treatment. In 10 of the 45 patients, adequate pressure control was not achieved after implantation of the stent, requiring a new Þltering operation to be carried out.

8.4.5.2Phacoemulsification Cataract Surgery Combined with Implantation of a Trabecular Stent

Possibly the most favorable scenario for the use of the trabecular stent is combined surgery with phacoemulsiÞcation [12, 13]. Implantation of the stent during cataract surgery can produce an additional pressure decrease that makes it possible to reduce or eliminate the need for pharmaceutical antiglaucoma treatment. This study was designed to evaluate the efÞcacy and safety of the trabecular stent associated with conventional phacoemulsiÞcation.

Fifty-nine patients were included in a prospective, multicenter, nonrandomized study. The surgical technique used was that described previously, with no signiÞcant intraoperative complications being recorded. The average age of the operated patients was 74.6 (range: 28Ð87) years. As in the previous case, the majority of patients had primary open-angle glaucoma (75.6%) and a small percentage had pigmentary or pseudoexfoliative glaucoma. At the time of the surgery, all antiglaucoma treatment was discontinued and was reintroduced gradually at the discretion of the investigator.

At baseline, average medicated IOP was 21.5 (±4.1) mmHg [mean (±SD)]. At 12 months, mean IOP had dropped to 17.4 (±3.2) mmHg, a mean IOP reduction of 4.3 (±4.9) mmHg (17.5%) (Fig. 8.54). At baseline, patients were taking a mean 1.7 (±0.9) medication. By 12 months, the mean number of medications was reduced to 0.6 (±0.9) (Fig. 8.55). Sixty-six percent (35/53 eyes) of all patients reached IOP ≤18 mmHg and almost half the patients (24/53) achieved an IOP ≤18 mmHg with no ocular hypotensive medications. The most commonly reported device-related adverse events were reports of stent malposition (9 eyes) and stent lumen obstruction (7 eyes). Of the 9 reports of stent malposition, 3 underwent treatment (replacement,