Optical coherence tomography angiography (OCTA) is a new and non-invasive imaging technique that is able to detect blood flow signal in the retina and the choroid within seconds. OCTA is different from the traditional angiography methods. The major advantages of OCTA are that it can observe blood flow signal in different layers of the retina and the choroid without injecting any dye, provide blood flow information that traditional angiography cannot provide, and enrich pathophysiological knowledge of the retinal and choroidal vascular diseases., which help us to make an accurate diagnosis and efficient evaluation of these diseases. However there is a large upgrade potential either on OCTA technique itself or on clinical application of OCTA. We need to fully understand the advantage and disadvantage, and differences of OCTA and traditional angiography. We also need to know how to interpret the result of OCTA. With that we could make a fast diagnosis in a non-invasive way and improve our knowledge of the retinal and choroidal vascular diseases.
As a new and non-invasive imaging technology, optical coherence tomography angiography (OCTA) has been using in ocular fundus diseases, glaucoma and neuro-ophthalmic disorders for more than 4 years. The most valuable and efficient application of OCTA is in detecting neovascular diseases in the macula. The big advantage of OCTA is for diagnosing all kinds of choroidal neovascularization. OCTA can observe blood flow information in different layers of the retina. To a large extent, it changes our diagnostic thinking and pathway in macular diseases. Before acquiring OCTA image, the operator should be well trained to ensure to get high quality images with good signal strength and less artifact. OCTA report should show the segmentation slab that the ophthalmologist wants to see. So far, OCTA has difficulty to reach peripheral retina with default setting. Even so, OCTA has provided much information of blood flow within retinal vascular arcade for evaluating structural and functional changes. We are expecting that the swept source OCTA could give us better observation of the choroidal blood flow. That should be the breakthrough of the new generation of OCTA.
OBJECTIVE: To review the role of thyroid hormone in the peripheral nerve regeneration. METHODS: The recent literatures of experimental study and clinical application on the role of thyroid hormone in nerve regeneration were reviewed. The researches on expression, isoform and changes of thyroid hormones in rat sciatic nerve in normal or injury were summarized. The effect of thyroid hormone on local rat sciatic nerve was studied, too. RESULTS: Nuclear thyroid hormone receptors expressed in numerous nuclei of sciatic nerve during a limited period of development extending from the third week of embryonic life to the end of the second postnatal week and after injury of adult sciatic nerve. A single and local administration of thyroid hormone at the level of the transected sciatic nerve produced a lasting effect on peripheral nerve regeneration. CONCLUSION: The beneficial effects of thyroid hormones upon injured peripheral nerve may have considerable therapeutic potential.
ObjectiveTo systematically evaluate the association between eNOS gene a/b polymorphism and diabetic retinopathy susceptibility. MethodsPubMed, EMbase, The Cochrane Library (Issue 5, 2015), CBM, CNKI, VIP and WanFang Data were systemically searched from inception to May 2015, to collect case-control studies about the eNOS a/b polymorphism and diabetic retinopathy susceptibility. Two reviewers independently screened literature, extracted data and evaluated the risk bias of included studies. Then, meta-analysis was performed by RevMan 5.2 software. ResultsA total of 16 case-control studies were included, which involved 3 232 diabetic retinopathy cases and 3 555 controls. The results of meta-analysis showed that, in the total analysis, the a/b polymorphism of the eNOS gene was not associated with diabetic retinopathy risk (dominant model:OR=0.94, 95%CI 0.78 to 1.15, P=0.57; recessive model:OR=0.97, 95%CI 0.78 to 1.22, P=0.88; aa vs. bb:OR=0.89, 95%CI 0.71 to 1.12, P=0.32; ab vs. bb:OR=0. 94, 95%CI 0.77 to 1.14, P=0.52; a vs. b:OR=0.97, 95%CI 0.82 to 1.14, P=0.70); In the subgroup analysis by ethnicity, the a/b polymorphism was significantly associated with the risk of diabetic retinopathy in Africans, but not in Asians and Caucasians. ConclusionThe a/b polymorphism in the eNOS gene may be a risk factor of diabetic retinopathy in Africans.