Objective: To evaluate the clinical effect of non-penetrating trabecular surgery (NPTS) with reticulated sodium hyaluronate implant in primary open-angle glaucoma (POAG).
Methods: NPTS with reticulated sodium hyaluronate implant was performed on 27 eyes of 25 patients with POAG. The procedure consisted of excising a deep scleral tissue including the external wall of the Schlemm's canal under a scleral flap without opening the anterior chamber, as the inner wall of the canal was left in place. Then placing a 3.0 mm x 4.5 mm x 0.5 mm or 3.5 mm x 3.5 mm x 3.5 mm reticulated sodium hyaluronate implant was placed under the flap, so that the aqueous humor may filter through the thin layer of trabeculocorneal membrane spontaneously without forming a flat chamber. The postoperative intraocular pressure (IOP), inflammation and filtering bleb were analyzed. All of patients undertook ultrasound biomicroscopy (UBM) and gonioscopy to evaluate the surgical site on the postoperative 2 weeks, 3, 6 and 9 months. The mean follow-up was (6.61 plus minus 2.47) months.
Results: The IOP decreased from a mean preoperative value of (26.36 +/- 9.02) mm Hg (1 mm Hg = 0.133 kPa) to a mean postoperative value of (14.18 +/- 3.51) mm Hg (t = 6.875, P < 0.05). The number of anti-glaucomatous medications, topical or systemical, was reduced from (2.96 +/- 1.43) sorts preoperatively to (0.77 +/- 1.07) sorts postoperatively. The visual acuity remained stable (no statistical difference with chi(2) test). Six eyes had elevated IOP after operation and were controlled by eyedrops or trabecular puncture with ND: YAG laser. A slight hyphema occurred in 4 eyes with small puncture during operation. The complications such as flat chamber, inflammation and choroidal detachment were not observed. The UBM showed that the sodium hyaluronate implant degraded and a transparent liquid space existed under the scleral flap in all of patients at postoperative 3 months. The gonioscopy showed that at the surgical site the thinner and semitransparent trabecular membrane and changes of a transparent cavity could be seen in 23 eyes. In the other eyes, at the site the trabecula was translucent. The filtering blebs were formed in 8 eyes.
Conclusion: Non-penetrating trabecular surgery with reticulated sodium hyaluronate implant can effectively lower the IOP and reduce the sorts of anti-glaucomatous medications. The visual acuity may remain unchanged, and no serious complications commonly seen in the traditional trabeculectomy occur. The procedure is a new simple and effective one for the treatment of POAG.