[Wound healing modulation in glaucoma surgery]

Crosslinked Sodium Hyaluronate Implant in Deep Sclerectomy for the Surgical Treatment of Glaucoma

Purpose

To evaluate the efficacy and safety profile of a new crosslinked sodium hyaluronate drainage implant in nonpenetrating glaucoma surgery.

Methods

From July 2008 until January 2010, 55 eyes from 55 patients with glaucoma were operated upon. After a standard deep sclerectomy was performed, a crosslinked sodium hyaluronate (HEALAflow®) was injected under the superficial scleral flap and underneath the conjunctiva. The main outcomes measured were mean intraocular pressure (IOP), mean number of antiglaucoma medications, presence of postoperative complications, and clinical aspect of the filtering bleb.

Results

For the 55 eyes, the mean follow-up was 12.0±5.1 months, the mean preoperative IOP was 21.6±7.2 mmHg, and the mean number of antiglaucoma medications before surgery was 2.4±1.2. At final follow-up visits, the mean IOP went down to 11.5±3.0 mmHg; the mean number of antiglaucoma medications was reduced to 0.5±0.9. The filtering bleb was visible on 49 eyes (89%). There were 5 hypotonies (IOP < 6 mmHg) and 3 iris incarcerations. Complete success rate (IOP ≤18 mmHg without antiglaucoma medication) was 70% and the overall success rate (IOP ≤18 mmHg with and without antiglaucoma medication) was 91%.

Conclusions

The slow resorbable highly crosslinked sodium hyaluronate drainage implant fills up the intrascleral and subconjunctival space, preventing postoperative scarring and fibrosis of the filtering site and helping to maintain a functional filtration after nonpenetrating glaucoma surgery. The IOP was significantly lowered with few numbers of postoperative complications and less medication.

[Treatment of glaucoma in patients with dry eye syndrome]

The treatments of glaucoma or ocular hypertension are associated with numerous ocular surface changes. Similarly, these ocular surface modifications directly impact the effectiveness of these therapies. The management of patients with glaucoma or ocular hypertension also suffering from dry eye syndrome needs to reduce eye drop-induced toxicity as well as a specific treatment for the ocular surface.

The influence of He-Ne laser on scar formation after trabeculectomy in rabbits

AIM

To investigate the influence of He-Ne lasers on scar formation in the filtration canal after trabeculectomy in a rabbit model, as well as to explore the mechanisms for preventing scar formation when using He-Ne lasers in vivo.

METHODS

Experiment 1: Four groups were established (four eyes in each group). In 12 eyes, the upper nasal limbus area next to the upper rectus muscle received 10 minutes of He-Ne laser irradiation (100, 150, 200mW/cm(2); 60, 90, 120J/cm(2)) every day for three days. Four eyes served as controls. Twenty-four hours after the final irradiation, the rabbits were sacrificed and the irradiated tissue was excised, fixed with paraformaldehyde and tested for proliferating cell nuclear antigen (PCNA), connective tissue growth factor (CTGF) and apoptosis (TUNEL). Experiment 2: Forty-two rabbits were randomly divided into two groups and standard trabeculectomy was performed in the right eyes either after 200mW/cm(2) He-Ne laser irradiation or not in the filtration area. The expression of PCNA and CTGF, apoptosis and collagen density in the filtration area were tested on the 7(th), 14(th) and 28(th) day after surgery.

RESULTS

Experiment 1: There were no more PCNA and CTGF positive cells in the He-Ne irradiation group than in the control group. No apoptotic cells were found in either group. Experiment 2: The expression of PCNA and CTGF was lower in the He-Ne irradiation group than in the control group on the 7(th) and 14(th) day after trabeculectomy surgery (P<0.05); no apoptotic cells were detected in either group. Collagen density was significantly lower in the He-Ne irradiation group than in the control group on the 14(th) and 28(th) day after surgery (P<0.05).

CONCLUSION

Pretreating the filtration area with 200mW/cm(2) (120J/cm(2)) of He-Ne laser irradiation may be helpful in preventing scar formation after trabeculectomy, possibly due to the downregulation of the expression of PCNA, CTGF and collagen synthesis in fibroblasts.