[Deep nonpenetrating sclerectomy and open angle glaucoma. Intermediate results from the first operated patients]

The aim of this retropective study is to evaluate and to compare in glaucoma patients, the mid-term results of the non penetrating deep-sclerectomy (NPDS) with collagen implant or with per operative application of 5 fluorouracile (5 FU).

The aim of the NPDS, a new filtering surgical procedure, is to remove under a scleral flap the Schlemm's canal and the juxtacanalicular trabecular meshwork responsible for the outflow resistance in order to obtain a sub-conjunctival filtration of the aqueous humor with no opening of the anterior chamber. Forty-two open angle glaucoma patients with uncontrolled intra-ocular pressure and with no risk factor of bleb fibrosis, underwent a NPDS. In 27 eyes (group 1) a sponge soaked with 5 FU (50 mg/ml) was applied for 5 minutes in the scleral bed, and in 15 eyes (group-2) a collagen implant (Staar*) was sutured in the scleral bed. A complete ophthalmologic examination was performed on days 1, 8, months 1,2,3 and each 3 months until the end of the follow-up. In case of increased IOP, goniopuncture with the Nd: YAG laser was performed at any time of the post operative period.

The mean intra-ocular pressure (IOP) significantly decreased from 23.5 +/- 5.1 mmHg to 15.5 +/- 2.9 at 11.1 +/- 5.6 months follow-up (group 1, p < 10(-3)) and from 22.6 +/- 6.9 Hg to 16.2 +/- 3.9 mmHg at 8.8, 3.6 months follow-up (group 2, p < 10(-3)) with a significant decrease in the medical treatment (p < 10(-3)). The Kaplan Meier probability of success (IOP < or = 20 mmHg without treatment and with no visual field deterioration) at 6 and 12 months was similar in both groups: 57.3% (group 1) and 66.0% (group 2) with a mean decrease in IOP of 30%. Goniopuncture had to be performed in more than one third of case in each group and was effective to control the IOP in half of the cases. No complication related to hypotony or inflammation occured in the post operative period.

NPDS is an interesting alternative to the classical trabeculectomy since the post operative complications are markedly reduced. However, the mid-term control in IOP appears to be slightly lower. The use of a collagen device does not lead to better control in IOP as compared to the use of a sponge of 5 FU.