Objective To establish an rat model of the Anterior Isc hemic Optic Neuropathy (rAION), and identify its reliability by observing the fundus, fluorescein fundus angiography (FFA),optical coherence tomography (OCT), v isually evoked potential (VEP) and histopathology. Methods Thirty male Sprague-Dawley rats were randomly divided into group Naive with 5 rats, group Laser with 5 rats, group hematoporphyrin derivative(HPD) with 5 rats, group rAION with 15 rats. All of the right eyes were the experimental eyes and the left ones were the control. after administration of HPD in rats` vena caudalis. The rats in group Laser were treated with a krypton red 647nm/2/3disc spot laser for 120 seconds, the rats in group HPD were treated by administration of HPD in rats` vena caudalis, and the rats in group Na?ve were not treated. Results From 1 day to 6 day s after rAION induction, the ON was pale and swollen in the superior part. The ON at 90 days after induction was pale and shrunken.30 minutes after rAION induction, hyperfluoresc ence appeared in the superior part of the optic disc, and the hypofluorescence in the 23rd day. In early FFA, hypofluorescence appeared at the ischemic area of the optic disc, and in midst and later stage the ischemic area revealed hyperflu orescence in the 1st day after rAION induction, the hypofluorescence in midst and later stage in the sixth day after r-AION model. The latent period of F-VEP expanded. The amplitude cut down in the 1-2 days after r-AION induction and did not changed in 35nd day. The surface of optic disc showed higher and rougher tha n the surface of retina in the 6th day after r-AION induction in OCT. After fixation and hematoxylineosin staining of 6-mu;m sections, in high power field the o pt ic disc showed edema with the displacement of retina surrounding the disc 1 day after treatment. Rarefaction and degeneration in the nerve fiber of retina and r eduction of the number of nuclei of ganglion cells in the 23st day after the mod el induction, and the thinning of nerve fiber of the optic disc and its surround ings. In contrast, there was no change in group Na?ve, group Laser and group HPD. Conclusions The r-AION model is like the human AION in fundus, FFA, OCT, VEP and histopathology. The rAION model provides the ischemic changes of occurrence of AION, and is helpful for the fundamental study of the AION. (Chin J Ocul Fundus Dis,2008,24:90-94)
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.
Objective To observe the results of multifocal visual evoked potential (mfVEP) examination in patients with anterior ischemic optic neuropathy (AION) before and ater treatment, and to probe its clinical significance. Methods A total of 90 patients (90 eyes) with AION were examined by mfVEP; the secondorder reaction of mfVEP was analyzed.The reaction was divided into upper and lower hemi field of visual field, or 1/4 quadrant visual field (superior nasal, inferior nasal, superior temporal, and inferior temporal). The sum of waves of each response was analyzed and the results in various regions were compared.The features of wave configuration was compared between the AION eyes and the contralateral eye, and between the AION eyes before and after treatment.Results The amplitude and latency of P-wave of mfVEP was 0.198plusmn;0.033 and 100.197plusmn;7.354 respectively in AION eyes before treatment, and was 0.271plusmn;0.024 and 98.567plusmn;6.794 in the contralateral eyes; the difference was significant (t=16.556,18.330; Plt;0.01). The amplitude and latency of P-wave of mfVEP was 0.229plusmn;0.016 and 100.104plusmn;10.603 respectively in AION eyes after treatment, which differed much from that before the treatment (t=13.649, 8.858; Plt;0.01) and also from that of the contralateral eyes (t=13.649，8.858；P＜0.01). ConclusionsThe amplitude and latency of P-wave of mfVEP may accurately reflect the recovery of local optic nerve damage in AION eyes before and after treatment with good repeatability. AION can be used as a new method for AION diagnosis and detection of the prognosis.
ObjectiveTo evaluate the occurrence of nocturnal hypotension (NHP) in nonarteritic anterior ischemic optic neuropathy (NAION). MethodsA evidence-based medicine study. Chinese and English as search terms for NAION and NHP was used to search literature in PubMed of National Library of Medicine, Embase, Web of science, Cochrane Library, Clinical Trials, Wanfang, and China National Knowledge Infrastructure and China Biology Medicine disc. Incomplete or irrelevant literature and review literature were excluded. The literature was meta-analyzed using Review Manager 5.4 and STATA 15.0. The 95% confidence interval (CI) were selected as the estimated value of effect size, the occurrence of NHP in NAION was calculated, and sensitivity analysis and publication bias analysis were also performed to assess the robustness of pooled outcomes. ResultsAccording to the search strategy, 159 articles were initially retrieved, and 8 articles were finally included for meta-analysis, three prospective studies and five retrospective studies. The occurrence of NHP in NAION was 43% (95%CI, 0.36-0.50). Sensitivity analyses confirmed that the evidence was robust. Subgroup analyses showed that the occurrence of NHP in NAION nearly the same in White patients (47%, 95%CI 0.39-0.55) and Chinese patients (41%, 95%CI 0.32-0.51). The occurrence of NHP in NAION was higher in using night mean artery pressure (45%, 95%CI 0.31-0.60) as the diagnostic criteria than using night systolic blood pressure & night diastolic blood pressure (40%, 95%CI 0.32-0.50). ConclusionsThe occurrence of NHP in NAION was 43%; the occurrence was similar in patients of different ethnicities. The diagnosis rate could be improved by using nMAP ＜ 70 mm Hg (1 mm Hg=0.133 kPa) as a diagnostic criterion for NHP. Careful intervention should be taken for the blood pressure of patients with NAION and NHP.
Objective To observe the characteristics of multifocal microperimetry and its relationship with visual acuity and multifocal ganglion cell complex (GCC) in nonarteritic anterior ischemic optic neuropathy (NAION). Methods A retrospective case study. A total of 38 patients (54 eyes) with NAION were enrolled in this study. 25 NAION eyes (25 patients) and 29 contralateral health eyes (29 patients) were randomly selected into case group and control group respectively. All eyes underwent best corrected visual acuity (BCVA), slit lamp microscope, indirect ophthalmoscope, color fundus photography, optical coherence tomography (OCT), visual field and multifocal microperimetry. Logarithm of the minimum angle of resolution (logMAR) was used to calculate BCVA. There were no significantly differences on age (t=?0.647), gender, dominant eyes ( χ2=0.128, 0.099), intraocular pressure (t=0.376) between two groups (P>0.05). Macular GCC thickness, superior and inferior GCC thickness were measured by OCT, focal loss volume (FLV) and global loss volume (GLV) were obtained at the same time. Microperimetry were measured by macular integrity assessment instrument (MAIA microperimetry), and mean retinal sensitivities (MS) in macular area 10° and fixation rate in the macular central 2° and 4° were determined. The relationship between MS, macular GCC and BCVA were analyzed by Spearman correlation analysis. Results The mean logMAR BCVA of case group and control group were 0.68±0.79 and 0.07±0.06, respectively. There was significantly statistical difference in MS between two groups (t=?2.507, P=0.037). There were no significantly statistical difference in mean GCC (t=?1.245, P=0.259), superior and inferior GCC (t=?1.336, ?1.024; P=0.230, 0.346), FLV (t=1.058, P=0.331) and GLV (P=0.182) between two groups. The correlation between BCVA and MS (r=?0.809, P=?0.005) was observed. However, there were no correlation between BCVA and GCC, superior and inferior GCC, FLV, GLV (r=?0.98, ?0.466, ?0.061, 0.442, 0.442; P=0.817, ?0.244, 0.885, 0.273, 0.273). And also, there were no correlation between MS and GCC, superior and inferior GCC, FLV, GLV (r=0.238, 0.524, 0.286, 0.643, ?0.619; P=0.570, 0.183, 0.493, 0.086, 0.102). Conclusions MS reduced in early stage NAION eyes, which did not correlate with macular GCC.
Objective To establish and evaluate a rat model of nonarteritic anterior ischemic optic neuropathy (NAION). Methods The rats were randomly divided into control group (n=13), sham laser group (n=11) and NAION group (n=23). The right eye was set as the experimental eye. NAION model was induced by directly illuminating the optic nerve (ON) of the right eye with 532 nm green laser, after intravenous infusion with the photosensitizing agent Rose Bengal. Sham laser treatment consisted of illuminating the ON region with 532 nm laser without Rose Bengal injection. Rats in control group underwent no intervention. The appearance of optic disc was observed with funduscope at 12 hours, 1, 3, 7, 28 days post-illumination. The histologic changes in the retina and ON of the NAION model were evaluated qualitatively with hematoxylin and eosin (HE) staining and transmission electron microscopy. The retrograde-labeled retinal ganglion cells (RGC) were counted on photographs taken from retinal flat mounts in a masked fashion. Results The optic disc in NAION eyes were swollen 3 days after photodynamic treatment. HE-stained longitudinal ON sections of NAION revealed vacuolar degeneration on day 3 after induction. Besides, ultrastructural study showed axonal edema and collapsed sheaths in the ischemic optic nerve at the same time point after modeling. ON edema resolved 7 days after induction. The final results revealed optic disc atrophy, extensive axonal loss, severe glial scar, and RGC death in large numbers 4 weeks after modeling. There were no aforementioned manifestations in control and sham laser group. The RGC density of the right eyes was statistically significantly lower in NAION group than that in control group and in sham laser group (t=?14.142, ?14.088; P=0.000, 0.000). The survival rate of RGC was statistically significantly lower in NAION group than in control group and in sham laser group (t=?17.048, ?16.667; P=0.000, 0.000). There was no difference of RGC density and survival rate of RGC between control and sham laser group (t=0.050, 0.348; P=0.961, 0.731). Conclusion A rat model of NAION was established successfully by photodynamic treatments with Rose Bengal, which induce optic nerve damage and RGC death.
Objective To observe the expression of triggering receptor expressed on myeloid cells (TREM), Caspase-3 and interleukin (IL)-6 in optic nerve tissue of ischemic optic neuropathy (ION). Methods Twenty Sprague-Dawley rats were randomly divided into control group and model group, 10 rats in each group. The permanent ligation of bilateral internal carotid arteries (BICA) was performed for 14 days to establish sub-acute ION model as model group. The control group were separated BICA without ligation. The expressions of TREM-1, TREM-2, Caspase-3 and IL-6 in rat retina were detected by reverse transcription PCR and Western blot, respectively. ResultsCompared with the control group, the expressions of TREM-1, Caspase-3, IL-6 mRNA (t=6.058, 7.86, 6.055) and protein (t=9.671, 9.524, 14.501) in the optic nerve tissue of the model group were increased, while the expression of TREM-2 mRNA and protein (t=9.283) was decreased, and the difference was statistically significant (P＜0.05). Conclusion In ischemic optic nerve tissue, TREM-1 mRNA and protein were significantly expressed, the expressions of TREM-2 mRNA and protein decreased significantly.
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 observe the clinical profile and risk factors of non-arteritic anterior ischemic optic neuropathy (NAION). MethodsProspective study was conducted to consecutively recruit 73 patients with NAION from October 2013 through September 2015. A detailed history of previous systemic diseases, smoking and drinking was collected, and a comprehensive ophthalmic evaluation was performed. The prevalence of associated risk factors in NAION patients were compared to the 146 age-and gender-matched normal subjects, and assessed in logistic regression model. ResultsOf the 73 patients, 65.75% were males, 34.25% were females. The mean age was (55.18±9.89) years. 21.92% were bilateral and 78.08% were unilateral. Arcuate visual field defect (31.58%) was the most prevalent defect detected in unilateral NAION, and there were 8.93% fellow eyes with abnormal optic disc formation in incipient stage. Concentric visual field contraction (40.63%) was the most common in bilateral NAION. Obesity (OR=8.09, 95% CI: 2.94-22.23, P < 0.001) and diabetes (OR=4.72, 95% CI: 1.57-14.25, P=0.006) were significantly associated with NAION. While smoking was marginally associated with NAION (OR=2.76, 95% CI: 1.02-7.53, P=0.047). ConclusionsThe gender predisposition should be reconsidered in NAION. We should pay attention to the fellow eye in case of the incipient NAION patients. Diabetes and obesity are associated with NAION.
Non-arteritic anterior ischemic optic neuropathy (NAION) is one of the most common acute optic neuropathy in adult characterized with impaired visual acuity and visual fields. The pathogenesis of NAION mostly result from the interactions between the systemic risk factors (such as diabetes mellitus, night hypotension, hereditary) and the local ocular risk factors (such as small optic disc and vitreo-papillary traction). A fully promoted diagnosis and treatment of NAION are based on the higher levels of clinical evidence, as well as the comprehensive assessment of relationship between the systemic and ocular risk factors in the pathogenesis of NAION. Secondary optic neuropathy of NAION and the early diagnosis with effective treatment of the fellow eye would be highly emphasized.