[A randomized study of subconjonctival bevacizumab (Avastin®) injection for corneal neovascularization]

PURPOSE

The goal of this phase III, comparative, multicentric, randomized, double-blinded clinical trial was to investigate the superiority of subconjunctival bevacizumab injections versus placebo in the treatment of corneal neovascularization.

PATIENTS AND METHODS

We included 38 eyes (38 patients) with corneal neovascularization. Twenty patients received bevacizumab and 18 placebos. Patients received 3 monthly injections of either 5mg (0.2mL) bevacizumab or placebo. The main criteria of success was reduction of the surface area of corneal neovascularization after 3months (M3) versus baseline, as measured using semi-automatic analysis of color photographs.

RESULTS

The percentage of neovascularized corneal surface decreased by -8.6%±32.8 with bevacizumab, versus -2.6%±20.8 with placebo (p=0.5284). Four patients were determined to be responders (reduction of more than 30%), 3 in the bevacizumab group and 1 in the placebo group, all with neovascularization of less than 1year duration. When restricting the analysis to neovascularization of less than 1 year duration, the difference approached the threshold for significance (-31.8%±42.4 in the bevacizumab group and -0.9%±23.1 in the placebo group) (p=0.0637), as well as the number of responders (3/6 in the bevacizumab group versus 1/10 in the placebo group) (p=0.1181). No serious adverse event was reported.

CONCLUSION

This study shows the efficacy of subconjunctival bevacizumab injection in the reduction of neovascularized corneal surface area versus placebo, but only when the neovascularization has been present less than 1year. Nevertheless, the study did not attain the statistical power to pass the threshold of significance.

[Assessment of astigmatism associated with the iris-fixated ARTISAN aphakia implant: Anterior fixation versus posterior fixation, study of postoperative follow-up at one year]

PURPOSE

The goal of our retrospective, single-center study of a case series was to compare the total, corneal, and internal astigmatism, and the visual acuity at one year after combined or stand-alone surgery consisting of iris fixation of an iris-claw intraocular lens (ARTISAN aphakia) in aphakic patients, according to whether the lens was fixated to the anterior (n=21) or posterior (n=51) surface of the iris.

RESULTS

We did not find a significant difference between these two types of fixation for any of the studied variables. The surgically induced astigmatism was 1.67 D at 176° in group A versus 1.19 D at 11° in group P.

CONCLUSION

Although this surgery creates additional corneal astigmatism, it has not been proven that it differs depending on the type of fixation of the iris-claw. If we adhere to the notion that the posterior fixated iris-claw decreases the risk of endothelial decompensation in case the implant becomes disenclavated, then reverse iris fixation of the iris-claw makes sense.

Traitement simultané par photothérapie dynamique et triamcinolone intravitréenne des néovaisseaux associés à un décollement de l’épithélium pigmentaire

OBJECTIVE

To assess the advantages of a treatment combining dynamic phototherapy with intravitreally injected Kenacort (triamcinolone acetonide) administered on the same day for choroidal neovascularization with pigment epithelium detachment in age-related macular degeneration.

METHOD

This prospective study involved 24 patients (26 eyes) with pigment epithelium detachment. Each patient underwent dynamic phototherapy according to standard parameters, followed 2 h later by intravitreal injection of 4 mg Kenacort (triamcinolone acetonide) performed in the operating room. The effectiveness of the treatment was assessed with an ETDRS vision test and optical coherence tomography before the operation and again 1, 3, and 6 months later.

RESULTS

The group of 24 patients (26 eyes) included 17 women and seven men whose mean age was 77 years (+/-6). In half of the cases, it was the second eye affected by age-related macular degeneration. Major inflammatory reaction following intravitreal injection was resolved within 24 h by local anti-inflammatory treatment. Baseline visual acuity was 40 characters on the ETDRS (+/-15) and final vision was significantly improved to 43 characters (+/-19) after 3 months. Three patients (12%) had their vision improved by more than three lines. For 19 patients (79%), the treatment eliminated pigment epithelium detachment after 1 month, with no recurrence.

DISCUSSION

No single recognized treatment exists for pigment epithelium detachment. Photodynamic therapy has not proven effective, according to the TAP study. For the last few years, several teams have recommended intravitreal injections of Kenacort (triamcinolone acetonide) as a complement to photodynamic therapy to treat different types of choroidal neovascularization. This combination has also been tried in the treatment of pigment epithelium detachment associated with age-related macular degeneration, although the protocol has not yet been clearly established. In order to decrease the cost of treatment by reducing the transport back and forth between the patient's home and the hospital, we have administered this dual treatment on the same day and evaluated the benefits for the patient. We have obtained very satisfactory anatomical results, making it possible to proceed with low-vision rehabilitation, and eventually improve visual acuity.

CONCLUSION

The results of this study indicate that a level of efficiency at least as high as that of treatment at two different times for occult choroidal neovascularization complicated by pigment epithelium detachment can be achieved by a dual treatment the same day, with an accompanying reduction in cost.

2'5'-Oligoadenylate polymerase activity in the rat small intestine

2'5'-Oligoadenylates are potent protein synthesis inhibitors: they are synthesized by a polymerase which was first described in interferon-treated cells. This system may also be involved in a normal process of cell proliferation and differentiation, in the absence of any viral infection. The small intestine enterocyte has been investigated as a model to test this hypothesis. The presence of 2'5'-oligoadenylate polymerase activity is demonstrated in the intestinal mucosa of normal adult rats. The distribution of this enzyme, and of the enzymes degrading 2'5' oligoadenylates have been investigated on enterocyte pools selectively extracted, under mild conditions, from the different parts of the rat small intestine. Similar results were obtained with enterocytes extracted from the mucosa of germ-free animals.