Lacidipine,thiamine pyrophosphate and their combination on the ocular ischemic syndrome induced by bilateral common carotid artery ligation

AIM:To investigate the effect of lacidipine,thiamine pyrophosphate(TPP)and the combination of lacidipine and TPP against oxidative and inflammatory eye damage induced by bilateral common carotid artery ligation in rats.METHODS:Male albino Wistar rats were categorized as those who underwent sham surgery(SG),right and left common carotid cross-clamping and unclamping procedure(CCU),lacidipine+CCU(LCCU),TPP+CCU(TCCU),and combination of lacidipine and TPP(LTC)+CCU(LTCCU).One hour before anesthesia,the LCCU(n=6)received lacidipine(4 mg/kg,orally)and the TCCU(n=6)received TPP(20 mg/kg,intraperitoneally).The SG(n=6)and CCU(n=6)received the same volume of distilled water from the same route.After anesthesia(60 mg/kg ketamine,intraperitoneally),the necks of the rats were opened in the midline.Ischemia was created for 10min by placing clips on the right and left common carotid arteries.Rats in the SG only underwent subcutaneous incision.After 10min,the clips were removed and reperfusion was achieved for six days.Then,the animals were euthanized(120 mg/kg ketamine,intraperitoneally)and the levels of oxidant,antioxidant and proinflammatory cytokines in the eye tissues were determined.The retinal tissue of the eye was also examined histopathologically.RESULTS:Lacidipine,TPP,and LTC significantly prevent the increase in malondialdehyde,tumor necrosis factoralpha,interleukin-1β(IL-1β),and IL-6 levels,decrease in total glutathione levels,superoxide dismutase and catalase activities and histopathological retinal damage in eye tissue induced by bilateral common carotid artery ligation in rats.The impact of these drugs on protection is determined to be LTC>lacidipine>TPP.CONCLUSION:As a result of the study,it is concluded that LTC may be more effective than lacidipine and TPP alone in treating ocular ischemic syndrome.

Improved circulation in ocular ischemic syndrome after carotid artery stenting

Ocular ischemic syndrome is a chronic ischemic eye disease including a series of ischemic ocular and brain syndromes caused by carotid artery occlusion or stenosis. Because of the different degrees of ischemia, clinical manifestations of ocular ischemic syndrome are diverse, and it is difficult to diagnose in the initial stage. The main strategy to treat ocular ischemic syndrome is elimination of carotid stenosis. We presented a patient who recovered dramatically after carotid artery stenting. The pre-stenting arm-retinal circulation time of the patient＇s left eye was prolonged, and a large amount of microaneurysm appeared at the posterior polar and mid-peripheral aspects of the left retina. The post-stenting arm-retinal circulation time of the left eve decreased to 16.3 seconds, and the microaneurvsm almost disappeared.

Collapsin Response Mediator Protein-2-induced Retinal Ischemic Injury in a Novel Mice Model of Ocular Ischemia Syndrome

Background： Collapsin response mediator protein-2 （CRMP2） has been shown to be involved in ischemia/hypoxia （IH） injury. We determined whether CRMP2 modulates ischemic injury in the retinal of Ocular ischemic syndrome （OIS）. This study was to explore the molecular mechanisms underlying O1S in a novel mice model. Methods： Experiments were performed oil adult male C57/BL6 mice that received bilateral internal carotid arteries ligation for 1,2, or 4 weeks. The mice received injection of calpeptin group before occlusion for 4 weeks or not. The expression of CRMP2 in the retinal was exalnined by western blotting （WB） analysis and immunohistochemical analysis （IHC）. The effects of ischemic injury on retinal were evaluated by fundus examination, fundus fluorescein angiography, electroretinogram, cell cotinting of retinal ganglion cell （RGC）, and measurement of the thickness of the retina. Results： The veins dilated after chronic ischemia. In the electroretinography, the amplitudes of a- and b-waves kept diminishing in an ischemia time-dependent manner. Moreover, the tail vein-retinal circulation time prolonged in the l- and 2-week group. In comparison, thickness of the retina decreased gradually with the ischemia time elapsed. WB analysis showed the CRMP2 and p-CRMP2 levels decreased in the 2- and 4-week groups. The results of IHC analysis were compatible with our results of WB. The loss of RGCs, decrease of the total reaction time and reduction of CRMP2 was alleviated by intravitreal injection of calpeptin. Conclusions： These results revealed that bilateral ligation of the internal carotid artery causes retinal ischemia in mice. Moreover, CRMP2 might play a pivotal role during the ischemic injury in the retina and inhibit the cleavage of CRM P2 can ameliorate the IH injury.

Subfoveal choroidal thickness and volume in severe internal carotid artery stenosis patients

AIM：To demonstrate the differences of retinal and choroidal structure changes in internal carotid artery（ICA） patients of China by enhanced-depth imaging optical coherence tomography（EDI-OCT）.METHODS：A retrospective review was conducted of 46 patients with a diagnosis of ICA stenosis greater than 65% on only one side（the opposite ICA Stenosis had less than 40% stenosis） from June 2015 through June 2016.All of the patients were combined with amaurosis fugax,but without any abnormality with other ocular examination.Thickness and volume of choroid and retina were manually measured by EDI-OCT.Differences were compared between ICA stenosis eyes and fellow eyes.RESULTS：There were no significant differences in the retinal thickness,macular retinal nerve fiber layer（m RNFL） thickness,inner thickness,or outer retinal thickness between the ICA Stenosis group and the control group（P=0.834,0.187,0.552,and 0.903,respectively）.The mean central choroidal thickness of the ICA Stenosis group was significantly lower than that of the control group（239.70±23.76 μm vs 257.46±22.13 μm,P〈0.001）.The percentage of ICA stenosis was significantly associated with the central choroidal thickness,central retinal thickness,foveal center choroidal volume,and foveal center retinal volume（r=0.854,0.678,0.729,and 0.785,respectively;P〈0.001）.There were no significant differences in the retinal and choroidal volume values in the 4 inner and 4 outer sectors between the two groups.CONCLUSION：The choroidal thickness in severe ICA stenosis eyes is lower than in fellow eyes.The choroidal thinning may occur before the retinal changes in patients with ocular ischemic syndrome.Evaluations of choroidal thickness may be useful to choose the optimal therapeutic schedule for ICA patients.

Neovascular Glaucoma: An Update on Etiopathogenesis, Diagnostics and Management

Neovascular glaucoma (NVG) is a severe secondary and refractory *severe secondary conditio, that accounts for a varying prevalence between 0.01% to 5.1% of all glaucoma those studied in different regions of the world. **This is a pathological condition, which is caused by the new vessels over iris surface and followed by fibrovascular membrane formation over the trabecular meshwork, secondary to a local angiogenic stimulus. The fibrovascular membrane over trabecular meshwork obstructs the aqueous outflow at an angle of the anterior chamber. ***The obstruction in outflow of the aqueous results increase of intraocular pressure (IOP), within the eyeball. NVG results from a number of ocular and systemic conditions with retinal ischemia leading to anoxia as a mediator in over 95% of cases. Most of them are affected with proliferative diabetic retinopathy (PDR) followed by central retinal venous occlusion (CRVO), and ocular ischemic syndrome (OIS) along with other uncommon causes or all those causes that causes retinal anoxia which led to angiogenic activity in retina and iris of eye. Although NVG overall prevalence is low, but it is a dreadful condition led to blindness. The objective of this review is to provide detailed information on its basic and clinical aspects, to enable us to manage it logically. Here its etiopathogenesis, methods of early diagnosis and management are discussed. It was concluded that if NVG is detected earlier and managed systematically (both medical and surgical) along with an eye on alleviation of different aggravating factors of the retinal hypoxia, it could be a sight-saving measure to the affected person.