Peripapillary vessel density in healthy people, primary open-angle glaucoma, and normal-tension glaucoma

OBJECTIVE

To compare peripapillary vessel density using optical coherence tomography angiography (OCT-A) in eyes of healthy people, primary open-angle glaucoma (POAG), and normal-tension glaucoma (NTG).

METHODS

Thirty patients with POAG, 27 patients with NTG, and 29 healthy individuals in the control group were assessed. Capillary vessels in peripapillary retinal nerve fiber layer (RNFL) represented by whole image RPC (radial peripapillary capillary) density in an AngioDisc scan 4.5 × 4.5 mm centered on the optic disc, and ONH morphological variables (disc area, rim area, cup to disc area ratio (CDR)), and average peripapillary RNFL thickness were measured.

RESULTS

Differences in mean RPC, RNFL, disc area, rim area, and CDR between the groups were statistically significant (P < 0.05). The difference in RNFL thickness and rim area was not significant between NTG and healthy groups, while RPC and CDR showed a statistically significant difference between all pairs. The vessel density in the POAG group was 8.25% and 11.7% lower compared to the NTG and healthy groups, respectively; while the mean difference was less (2.97%) for the NTG and healthy group. In the POAG group, 67.2% of the variation in RPC can be explained by a model containing CDR and RNFL thickness, and in normal eyes 38.8% of the changes using a model containing RNFL.

CONCLUSION

The peripapillary vessel density is reduced in both types of glaucoma. The vessel density in NTG was significantly lower than in the healthy eyes, despite the lack of significant difference in RNFL thickness and neuroretinal rim area between them.

Long-term effects of intraoperative topical bevacizumab in sutureless scleral tunnel trabeculectomy: a prospective clinical trial

PURPOSE

To investigate the long-term efficacy and safety of the novel method sutureless trabeculectomy with topical administration of bevacizumab.

MATERIALS/METHODS

Primary open-angle glaucoma patients with intraocular pressure (IOP) > 21 mmHg despite maximum tolerated medication were included in a single-blind prospective interventional clinical trial. Group 1 underwent sutureless scleral tunnel trabeculectomy with intraoperative topical administration of bevacizumab (1.25 mg) applied on the scleral incision for 1 min. Group 2 underwent sutureless trabeculectomy alone and group 3 (control group) underwent conventional trabeculectomy with mitomycin C (MMC). Outcome measures were surgical success, IOP, number of needed anti-glaucoma medications, and complications. Patients were followed for two years.

RESULTS

Finally, 50 eyes from group 1, 46 from group 2, and 47 from group 3 were analyzed. At the end of 24 months, 52% (n = 26) of group 1, 34.8% (n = 16) of group 2, and 57.4% (n = 27) of group 3 had complete success (IOP < 18 mmHg without medication). The difference was only significant between groups 2 and 3 (p = 0.003). 94% (n = 47) of group 1, 89.1% (n = 41) of group 2, and 91.5% (n = 43) of group 3 had qualified success (IOP < 18 mmHg with ≤ 2 anti-glaucoma medications) (p = 0.69). There was a significant difference in the overall IOP mean between the three groups (p < 0.0001). There was no significant difference between the three groups in complication rates and the number of needed anti-glaucoma medications for IOP control.

CONCLUSION

Sutureless trabeculectomy with topical application of bevacizumab showed comparable surgical success rates with conventional trabeculectomy and MMC in long-term follow-up. Additionally, adjuvant use of topical bevacizumab had a significant positive impact on long-term IOP control.

Leishmania donovani infection differentially regulates small G-proteins

Leishmania is a protozoan parasite that resides and replicates in macrophages and causes leishmaniasis. The parasite alters the signaling cascade in host macrophages and evades the host machinery. Small G-proteins are GTPases, grouped in 5 different families that play a crucial role in the regulation of cell proliferation, cell survival, apoptosis, intracellular trafficking, and transport. In particular, the Ras family of small G-proteins has been identified to play a significant role in the cellular functions mentioned before. Here, we studied the differential expression of the most important small G-proteins during Leishmania infection. We found major changes in the expression of different isoforms of Ras, mainly in N-Ras. We observed that Leishmania donovani infection led to enhanced N-Ras expression, whereas it inhibited K-Ras and H-Ras expression. Furthermore, an active N-Ras pull-down assay showed enhanced N-Ras activity. L donovani infection also increased extracellular signal-regulated kinase 1/2 phosphorylation and simultaneously decreased p38 phosphorylation. In contrast, pharmacological inhibition of Ras led to reduction in the phosphorylation of extracellular signal-regulated kinase 1/2 and enhanced the phosphorylation of p38 in Leishmania-infected cells, which could lead to increased interleukin-12 expression and decreased interleukin-10 expression. Indeed, farnesylthiosalicyclic acid (a Ras inhibitor), when used at the effective level in L donovani-infected macrophages, reduced amastigotes in the host macrophages. Thus, upregulated N-Ras expression during L donovani infection could be a novel immune evasion strategy of Leishmania and would be a potential target for antileishmanial immunotherapy.