Effects of Postural Variation on Intra-ocular Pressure: Comparison between Pseudo-exfoliation Glaucoma and Primary Open Angle Glaucoma

Identification of circular RNA-Dcaf6 as a therapeutic target for optic nerve crush-induced RGC degeneration

The death of retinal ganglion cells (RGCs) can cause irreversible injury in visual function. Clarifying the mechanism of RGC degeneration is critical for the development of therapeutic strategies. Circular RNAs (circRNAs) are important regulators in many biological and pathological processes. Herein, we performed circRNA microarrays to identify dysregulated circRNAs following optic nerve crush (ONC). The results showed that 221 circRNAs were differentially expressed between ONC retinas and normal retinas. Notably, the levels of circular RNA-Dcaf6 (cDcaf6) expression in aqueous humor of glaucoma patients were higher than that in cataract patients. cDcaf6 silencing could reduce oxidative stress-induced RGC apoptosis in vitro and alleviate retinal neurodegeneration in vivo as shown by increased neuronal nuclei antigen (NeuN, neuronal bodies) and beta-III-tubulin (TUBB3, neuronal filaments) staining and reduced glial fibrillary acidic protein (GFAP, activated glial cells) and vimentin (activated glial cells) staining. Collectively, this study identifies a promising target for treating retinal neurodegeneration.

The effect of trabeculectomy and glaucoma drainage device implantation on postural intraocular pressure changes in glaucomatous eyes

PURPOSE

To investigate the effect of trabeculectomy and glaucoma drainage device implantation on posture related intraocular pressure (IOP) changes in glaucomatous eyes.

METHODS

Eyes in this prospective study were divided into three groups: those that underwent Ahmed glaucoma valve implantation (Ahmed group), those that underwent trabeculectomy with mitomycin C (trabeculectomy group) and those treated medically (medication group). IOP was measured in the sitting position, and after 15 min in the left lateral decubitus position using a Tonopen XL, and a Goldmann applanation tonometer (GAT). For GAT measurements in the left lateral decubitus position, we used a specialized system comprised of a motorized bed attached to a modified slit-lamp table.

RESULTS

111 eyes of 64 glaucoma patients were included in the analysis: 19 in the Ahmed group, 46 in the trabeculectomy group and 46 in the medication group. The difference in IOP between the sitting and supine positions was significant in the medication (2.23 mmHg) and trabeculectomy (1.48 mmHg) groups, but not in the Ahmed group (0.53 mmHg). This significance was reached with the GAT, but not with the Tonopen. A rise of 5 mmHg or more between the sitting and supine positions was documented in 5.2%, 4.3% and 15.2% of eyes in the Ahmed, trabeculectomy and medication groups, respectively. Intraclass correlation coefficient for IOP measurements in the supine position demonstrated good correlation between the two tonometers.

CONCLUSIONS

Ahmed valve surgery significantly reduces postural IOP response as compared with medically treated controls. There was no significant difference between Ahmed valve and trabeculectomy in terms of their effect on the postural IOP change.