Unterschiedliche Effekte der Trabektomoperation auf unterschiedliche Glaukomformen

PURPOSE: Ab interno trabeculotomy using the trabectome device is a intraocular pressure (IOP) decreasing operation by ablation of the trabecular meshwork and the inner wall of Schlemm's channel. This prospective study analyses the effectiveness of the trabectome operation in 122 patients.

PATIENTS AND METHODS: The operation was conducted when topical medication was maxed out with the intraocular pressure (IOP) remaining above the desired target range. In addition to the evaluation of the whole study group further analysis concerned the effectiveness of the trabectome in different subclassifications of glaucoma. In some cases the procedure was combined with cataract surgery and subsequently the results were compared to the plain trabectome OP. The results were split into two groups: "complete success" (without postoperative medication) and "qualified success" (with medication). The evaluation was processed for the IOP levels ≤ 21 mmHg, ≤ 18 mmHg, ≤ 15 mmHg und ≤ 12 mmHg. Follow-up dates were 6 and 12 months after surgery.

RESULTS: Baseline IOP was 20.15 ± 7.1 mmHg. After 6 months the average IOP of all patients was 16.53 ± 5.89 mmHg, after 12 months the IOP amounted to 15.6 ± 4.45 mmHg. At both follow-ups approximately 90 % of the "complete success" group exhibited an IOP ≤ 18 mmHg. Also at both follow-ups 75 % of the "qualified success" group achieved a range ≤ 18 mmHg - whereas 50 % gained an IOP ≤ 15 mmHg. In secondary glaucoma an IOP decrease of 36 % was achieved. In open-angle glaucomas and those with dysgenetic altered angles the operation evoked a pressure loss of ca. 20 %. The trabectome-only group as well as the group of combined surgery exhibited a significant lowering of IOP. This was accomplished by a significant reduction of eye drops. After surgery nearly half of all patients required none or 1 eye drop at most.

CONCLUSION: The trabectome offers a safe and significant lowering of IOP for around 36 % and seems to be very effective in secondary glaucomas. In dysgenetic alterations and open-angle glaucoma a moderate lowering of IOP (ca. 20 %) may be expected. The amount of eye drops can be reduced for about 42 %. After surgery every second patient requires at most 1 eye drop. The technique can be combined with cataract surgery and permits a penetrating operation at a later date.