ObjectiveTo observe the changes in subfoveal choroidal thickness (SFCT) and peripapillary choroidal thickness (pCT) in nonarteritic anterior ischemic optic neuropathy (NAION).MethodsNineteen newly occurred NAION patients were included. The patients were divided into group A (20 affected eyes of 19 patients) and B (18 fellow eyes of 18 patients). Twenty eyes of 20 age, gender, intraocular pressure and axial length-matched healthy volunteers (group C) were enrolled in this study. The differences of age (t=1.58), gender ratios (χ2=0.107), intraocular pressure (t=0.092) and axial length (t=0.148) between 3 groups were not significant (P＞0.05). SFCT, pCT were measured at first visit, 1 month and 3 months after treatment using enhanced deep imaging technique of spectral domain optical coherence tomography. The correlation of best corrected visual acuity (BCVA) and the choroidal thickness was investigated.ResultsAt the first visit, the mean SFCT and pCT in group A were significant thicker than group C (t=2.957, 2.844; P=0.006, 0.009). There was no difference of SFCT and pCT between group B and C (t=2.019, 2.024; P=0.053, 0.057). There was no correlation between BCVA and SFCT, pCT (F=0.161, 0.033; P=0.695, 0.859). One month after treatment, SFCT in group A was still thicker than group C (t=2.803, P=0.009); while pCT was decreased in group A when compared to group C, but the difference was not significant (t=1.871, P=0.084). Three months after treatment, the differences of SFCT and pCT were not significant between group A and C (t=1.223, 1.105; P=0.236, 0.282).ConclusionsAt first visit, SFCT and pCT in NAION eyes showed a significant increase when compared to normal eyes. One month later, pCT in NAION eyes decreased to normal. Three months later, both SFCT and pCT decreased. These findings may suggest that a thickened choroid is a clinical characteristic at acute stage in NAION eyes.
ObjectiveTo investigate the neuroprotective effect of Benztropine on retinal ganglion cells (RGCs) death and optic nerve injury in rats model of non-arteritis anterior ischemic optic neuropathy (rNAION).MethodsA total of 25 Sprague-Dawley rats were randomly divided into Benztropine treatment group (n=13) and PBS control group (n=12). The right eye was set as the experimental eye. rNAION model was established by using rose Bengal combined with laser photodynamic method. The rats in the Benztropine treatment group were received intraperitoneal injection with Benztropine 10 mg/kg (0.2 ml) daily for 3 weeks, while the rats in the PBS control group were received intraperitoneal injection with an equal volume of PBS. At 1, 3 and 7 days after modeling, the retinal and optic disc conditions of the rats were observed by direct ophthalmoscopy. Retrograde labeling, fluorescence microscopy and transmission electron microscopy were used to observe the survival of RGCs and the damage of the optic nerve myelin and axon at 4 weeks after modeling. The RGCs density and survival rate of the two groups were compared by One-Way Anova.ResultsAt 1 and 3 days after modeling, the optic disc edema was observed in the rats of rNAION model group. At 7 days after modeling, the optic disc edema decreased and the boundary was blurred compared with 3 days after modeling.After 4 weeks, the RGCs density in the PBS group was 308±194/mm2 and the survival rate was 13.7%. The density of RGCs in the Benztropine group was 1173+868/mm2 and the survival rate was 47.6%. The differences of RGCs density and survival rate were significant between the two groups (F=7.552, 8.184; P=0.015, 0.012). Myelin disintegration, axon degeneration, onion-like body and gliosis were observed in the optic nerve sections of rNIAON in the PBS group, while the damage of axon and myelin structure in the Benztropine group was significantly less than that in the PBS group.ConclusionsBenztropine group showed higher RGC survival rate, less damage of axon and myelin structure on rNAION model. This study explored the potential neuroprotective effect of Benztropine.