Perforating scleral vessels adjacent to myopic choroidal neovascularization achieved a poor outcome after intravitreal anti-VEGF therapy

BackgroundThis study aimed to summarize the features of perforating scleral vessels (PSVs) in patients with myopic choroidal neovascularization (CNV) (mCNV) using optical coherence tomography angiography (OCTA) and to identify the associations with the response after intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy.MethodsA consecutive series of naïve patients who had mCNV and received intravitreal anti-VEGF therapy with a follow-up duration of 12 months or more were enrolled. The prevalence, location, and branches of PSVs were analyzed. Projection-resolved OCTA (PR-OCTA) was used to analyze the neovascular signals between CNV and PSVs. Best corrected visual acuity (BCVA) and central macular thickness (CMT) were measured. The proportion of CMT change relative to baseline was used to assess therapeutic response.ResultsA total of 44 eyes from 42 patients with mCNV were enrolled. PSVs were identified in 41 out of 44 eyes. Branches were identified in the PSVs of 24 eyes (57.14%), and 20 eyes did not have PSV branches (47.62%). In eight eyes (18.18%), PSVs were adjacent to mCNV, and in 36 eyes (81.82%), PSVs were not adjacent to mCNV. After anti-VEGF therapy for mCNV, BCVA increased (F = 6.119, p < 0.001) and CMT decreased (F = 7.664, p < 0.001). In the eyes where PSVs were adjacent to mCNV, BCVA improvements (F = 7.649, p = 0.009) were poor, and changes in CMT were small.ConclusionThe eyes with PSVs adjacent to mCNV showed poor therapeutic responses after intravitreal anti-VEGF therapy

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Repeatability and Reproducibility of Foveal Avascular Zone Area Measurements Using AngioPlex Spectral Domain Optical Coherence Tomography Angiography in Healthy Subjects

&lt;b&gt;&lt;i&gt;Purpose:&lt;/i&gt;&lt;/b&gt; The aim of this study was to evaluate the repeatability and reproducibility of foveal avascular zone (FAZ) area measurements using AngioPlex spectral domain optical coherence tomography (OCT) angiography in normal subjects. &lt;b&gt;&lt;i&gt;Methods:&lt;/i&gt;&lt;/b&gt; Twenty-two healthy subjects (25 eyes) underwent FAZ area measurements with AngioPlex OCT. Each volunteer was separately examined 3 consecutive times by the 2 experienced observers. The FAZ area was measured using ImageJ software. Intraobserver repeatability was evaluated by calculating the coefficient of variation (CoV) and intraclass correlation coefficient (ICC). Interobserver reproducibility was also assessed using the Bland-Altman test and concordance correlation coefficient (CCC). &lt;b&gt;&lt;i&gt;Results:&lt;/i&gt;&lt;/b&gt; The FAZ areas were measured as 0.373 ± 0.109 and 0.377 ± 0.112 mm&lt;sup&gt;2&lt;/sup&gt; by observers 1 and 2, respectively. The repeatability assessment of the FAZ area measurements yielded CoV values of 0.029 and 0.034 and ICC values of 0.997 and 0.996 by observers 1 and 2, respectively. The mean difference between the 2 observers was 0.004. CCC values ranged from 0.9705 to 0.9844. &lt;b&gt;&lt;i&gt;Conclusions:&lt;/i&gt;&lt;/b&gt; The FAZ area measurements obtained using AngioPlex OCT showed a good repeatability and reproducibility in healthy subjects. Excellent reliability makes AngioPlex OCT a valid device for measuring the FAZ area.</jats:p

Comparative analysis of macular characteristics in mCNV and contralateral eyes

PurposeTo illustrate the characteristics of perforating scleral vessels in macular regions between mCNV eyes and contralateral eyes in unilateral mCNV patients.MethodsThis was a retrospective study that included patients with unilateral naive mCNV. The study aimed to identify and analyze the distribution of perforating scleral vessels (PSVs) in the macular region of mCNV eyes and contralateral eyes. The central macular choroidal thicknesses (mChT) were measured using optical coherence tomography angiography (OCTA). The grades of myopic atrophic maculopathy (MAM) and macular myopic diffuse chorioretinal atrophy (DCA) were evaluated within groups. The number of PSVs and mChT were compared between contralateral and mCNV eyes based on the grade of DCA. The ROC curves were utilized to explore the diagnostic indexes for mCNV.ResultsA total of 102 eyes from 51 patients with unilateral mCNV were included. There was no significance in the severity of MAM or the grade of DCA between mCNV eyes and contralateral eyes (p = 0.074, p = 0.054, respectively). The mean number of PSVs in mCNV eyes was fewer than the contralateral eyes [1.00 (1.00–2.00) vs. 2.00 (0.75–3.00), p = 0.030]. The mChT in mCNV eyes was thinner than the contralateral eyes [36.00 (25.00–53.75) μm vs. 46.00 (31.00–75.25) μm, p = 0.001]. The mean grade of DCA in mCNV eyes was higher than that in contralateral eyes [3.00 (3.00–3.00) vs. 3.00 (2.00–3.00), p = 0.004]. When DCA involved the macular region, there were more PSVs in contralateral eyes than in mCNV eyes [1.50 (1.00–2.00) vs. 2.00 (1.00–3.00), p = 0.042]. Similarly, when DCA involved the foveal region, there were more PSVs in contralateral eyes than in mCNV eyes [1.50 (1.00–2.00) vs. 3.00 (2.00–4.00), p = 0.004]. The grade of DCA and mChT were valuable factors for predicting mCNV eyes (AUC = 0.6566, p = 0.021; AUC = 0.6304, p = 0.029; respectively). When the extent of DCA exceeded the foveal region, the count of PSVs was a good diagnostic factor for predicting mCNV (AUC = 0.7430, p = 0.003).ConclusionThe mean amount of PSVs was significantly lower in the mCNV eyes compared to the contralateral eyes. When the extent of DCA exceeded the foveal region, the count of PSVs was a good diagnostic factor for predicting mCNV. Myopic eyes with a higher grade of DCA and a thinner mChT were more likely to develop mCNV

Secondary choroidal neovascularization due to choroidal osteoma after 9 years follow-up

Abstract Background Choroidal osteoma is a benign intraocular tumor that can increase risk of developing choroidal neovascularization. The visual prognosis is influenced by the tumor location, decalcification status, overlying RPE atrophy, presence of choroidal neovascularization, persistence of subretinal fluid and occurrence of subretinal hemorrhages. Case presentation The authors present a 40-year-old woman diagnosed with choroidal osteoma of the right eye. Her best corrected visual acuity was 12/20 but decreased to 5/20 due to secondary choroidal neovascularization after 8 years follow up. Fundus examination revealed an enlarged choroidal osteoma in most margins at posterior pole with schistose hemorrhage beside macula. Optical coherence tomography angiography revealed unique features in the vascular changes of choroidal neovascularization in choroidal osteoma in the outer retinal layer and choroid capillary layers, and subretinal neovascularization. Indocyanine green fluorescence angiography showed there was hypo-fluorescence at the peripapillary with faint hyper-fluorescence at the macular, corresponding to the location on the fundus photograph. The patient received 3 injections of intravitreal ranibizumab. After 1 year follow up, her visual acuity of the right eye was 18/20 and the CNV had regressed. Conclusions We present the findings and treatment of a case of choroidal osteoma with secondary choroidal neovascularization. Optical coherence tomography angiography combined with FFA and ICGA is used to analysis the characteristics of secondary choroidal neovascularization. Optical coherence tomography angiography can reveal some unique characteristics in the vascular changes compared to fundus fluorescein angiography. </jats:sec

Metabolomic Study of a Rat Model of Retinal Detachment

Retinal detachment is a serious ocular disease leading to photoreceptor degeneration and vision loss. However, the mechanism of photoreceptor degeneration remains unclear. The aim of this study was to investigate the altered metabolism pathway and physiological changes after retinal detachment. Eight-week-old male SD rats were fed, and the model of retinal detachment was established by injecting hyaluronic acid into the retinal space. The rats were euthanized 3 days after RD, and the retinal tissues were sectioned for analysis. Untargeted lipid chromatography-mass spectrometry lipidomic was performed to analyze the metabolite changes. A total of 90 significant metabolites (34 in anionic and 56 in cationic models) were detected after retinal detachment. The main pathways were (1) histidine metabolism; (2) phenylalanine, tyrosine, and tryptophan biosynthesis; and (3) glycine, serine, and threonine metabolism. The key genes corresponding to each metabolic pathway were verified from the Gene Expression Omnibus (GEO) database of human retinal samples. The results indicated that the production of histamine by histidine decarboxylase from histidine reduced after RD (p &lt; 0.05). Xanthine, hypoxanthine, guanine, and guanosine decreased after RD (p &lt; 0.05). Decreased xanthine and hypoxanthine may reduce the antioxidant ability. The decreased guanosine could not provide enough sources for inosine monophosphate production. Tyrosine is an important neurotransmitter and was significantly reduced after RD (p &lt; 0.05). Citrate was significantly reduced with the increase of ATP-citrate lyase enzyme (ACLY) (p &lt; 0.05). We inferred that lipid oxidation might increase rather than lipid biogenesis. Thus, this study highlighted the main changes of metabolite and physiological process after RD. The results may provide important information for photoreceptor degeneration

A novel fault location method for multi-terminal transmission lines based on composite analysis of time-frequency fault traveling waves

In order to solve the problems such as complex fault branch determination, large fault location error and low error tolerance of the existing multi-terminal transmission line (MTTL) fault location method, due to the influence of fault traveling wave (FTW) wave head (WH) time extraction accuracy and network topology structure, a novel fault location method for MTTLs based on composite analysis of time–frequency FTW is proposed. The FTW location mechanism for MTTLs is firstly revealed. According to the characteristic that the FTW natural frequency (NF) is inversely proportional to the transmission distance, the fault branch determination vector is defined, and the corresponding principle is proposed to determine the fault branch. On this basis, the multi-terminal FTW data with adaptive FTW velocity capability are surface-fitted by using the characteristic that the transmission time of FTW is directly proportional to the transmission distance, so as to achieve fault precise location. The PSCAD/EMTDC simulation and laboratory test results show that this method has a simple fault location process and high location accuracy under various fault conditions, effectively reduces the influence of harsh environment, FTW velocity inhomogeneous and WH time extraction error on the location results, and has high error tolerance

High Responsivity Vacuum Nano-Photodiode Using Single-Crystal CsPbBr3 Micro-Sheet

Field electron emission vacuum photodiode is promising for converting free-space electromagnetic radiation into electronic signal within an ultrafast timescale due to the ballistic electron transport in its vacuum channel. However, the low photoelectric conversion efficiency still hinders the popularity of vacuum photodiode. Here, we report an on-chip integrated vacuum nano-photodiode constructed from a Si-tip anode and a single-crystal CsPbBr3 cathode with a nano-separation of ~30 nm. Benefiting from the nanoscale vacuum channel and the high surface work function of the CsPbBr3 (4.55 eV), the vacuum nano-photodiode exhibits a low driving voltage of 15 V with an ultra-low dark current (50 pA). The vacuum nano-photodiode demonstrates a high photo responsivity (1.75 AW&minus;1@15 V) under the illumination of a 532-nm laser light. The estimated external quantum efficiency is up to 400%. The electrostatic field simulation indicates that the CsPbBr3 cathode can be totally depleted at an optimal thickness. The large built-in electric field in the depletion region facilitates the dissociation of photoexcited electron&ndash;hole pairs, leading to an enhanced photoelectric conversion efficiency. Moreover, the voltage drop in the vacuum channel increases due to the photoconductive effect, which is beneficial to the narrowing of the vacuum barrier for more efficient electron tunneling. This device shows great promise for the development of highly sensitive perovskite-based vacuum opto-electronics