Otago glaucoma surgery outcome study: long-term follow-up of cases of primary glaucoma with additional risk factors drained by Molteno implants.

OBJECTIVE

This study was undertaken to provide data on the long-term results of cases of primary open-angle glaucoma with additional risk factors drained by Molteno implants in the province of Otago, New Zealand.

DESIGN

Prospective, noncomparative case series

PARTICIPANTS

One hundred thirty eyes of 103 patients drained by Molteno implants as the first surgery between 1984 and 1999.

INTERVENTION: Insertion of Molteno implant (Ethicon Inc., Johnson & Johnson, Somerville, NJ) using the Vicryl-tie technique.

MAIN OUTCOME MEASURES: Intraocular pressure (IOP), visual acuity, visual field.

RESULTS

Insertion of a Molteno implant controlled the IOP at 21 mmHg or less with a probability of 1.0 (95% confidence interval [CI], 0.90, 1.0) at up to 7 or more years after surgery. The mean preoperative visual acuity of 20/160 improved to 20/50 after operation and then declined to 20/55 at 5 years and 20/80 after 10 years. The probability of retaining useful vision (visual acuity, >20/400; visual field, >5 degrees radius) was 0.86 (95% CI, 0.77, 0.94) and 0.78 (95% CI, 0.67, 0.89) at 5 and 7 or more years, respectively, after surgery.

CONCLUSIONS

The insertion of Molteno implants using the Vicryl-tie technique in this series of 130 cases of primary open-angle glaucoma with additional risk factors controlled the IOP in all cases.