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1.
《Archivos de la Sociedad Espa?ola de Oftalmología》2022,97(8):432-442
PurposeTo develop and evaluate an automated method to measure the foveal avascular zone (FAZ) area in healthy eyes on Heidelberg Spectralis Optical Coherence Tomography Angiography (HS-OCTA). This method is referred to as the modified Kanno-Saitama macro (mKSM) which is an evolution of the Kanno-Saitama macro (KSM) approach.MethodsThis cross-sectional study included 29 eyes of 25 healthy volunteers who underwent HS-OCTA at the macular area twice at the same time. Regardless of the quality of the images, all of them were included. Macular data on the superficial vascular plexus, intermediate capillary plexus (ICP) and deep capillary plexus were processed by mKSM. The FAZ area was measured twice automatically using the mKSM and KSM and twice manually by two independent examiners.ResultsFrom 174 images, KSM could not measure correctly 31% while mKSM could successfully measure all of them. Intrascan intraclass coefficient ranged from 0.948 to 0.993 for manual measurements and was 1 for mKSM method. Despite that the difference between human examiners is smaller than between human examiners and mKSM according to Bland-Altman plots, the scatterplots show a strong correlation between human and automatic measurements. The best results are obtained in ICP.ConclusionsWith mKSM, the automated determination of the FAZ area in HS-OCTA is feasible and less human-dependent. It solves the inability of KSM to measure the FAZ area in suboptimal quality images which are frequent in daily clinical practice. Therefore, the mKSM processing could contribute to our understanding of the three vascular plexuses. 相似文献
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Diabetic macular ischaemia (DMI) is traditionally defined and graded based on the angiographic evidence of an enlarged and irregular foveal avascular zone. However, these anatomical changes are not surrogate markers for visual impairment. We postulate that there are vascular phenotypes of DMI based on the relative perfusion deficits of various retinal capillary plexuses and choriocapillaris. This review highlights several mechanistic pathways, including the role of hypoxia and the complex relation between neurons, glia, and microvasculature. The current animal models are reviewed, with shortcomings noted. Therefore, utilising the advancing technology of optical coherence tomography angiography (OCTA) to identify the reversible DMI phenotypes may be the key to successful therapeutic interventions for DMI. However, there is a need to standardise the nomenclature of OCTA perfusion status. Visual acuity is not an ideal endpoint for DMI clinical trials. New trial endpoints that represent disease progression need to be developed before irreversible vision loss in patients with DMI. Natural history studies are required to determine the course of each vascular and neuronal parameter to define the DMI phenotypes. These DMI phenotypes may also partly explain the development and recurrence of diabetic macular oedema. It is also currently unclear where and how DMI fits into the diabetic retinopathy severity scales, further highlighting the need to better define the progression of diabetic retinopathy and DMI based on both multimodal imaging and visual function. Finally, we discuss a complete set of proposed therapeutic pathways for DMI, including cell-based therapies that may provide restorative potential. 相似文献
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《Clinical neurophysiology》2019,130(1):128-137
ObjectiveHigh frequency oscillations (HFO) between 80–500 Hz are markers of epileptic areas in intracranial and maybe also scalp EEG. We investigate simultaneous recordings of scalp and intracranial EEG and hypothesize that scalp HFOs provide important additional clinical information in the presurgical setting.MethodsSpikes and HFOs were visually identified in all intracranial scalp EEG channels. Analysis of correlation of event location between intracranial and scalp EEG as well as relationship between events and the SOZ and zone of surgical removal was performed.Results24 patients could be included, 23 showed spikes and 19 HFOs on scalp recordings. In 15/19 patients highest scalp HFO rate was located over the implantation side, with 13 patients having the highest scalp and intracranial HFO rate over the same region. 17 patients underwent surgery, 7 became seizure free. Patients with poor post-operative outcome showed significantly more regions with HFO than those with seizure free outcome.ConclusionsScalp HFOs are mostly located over the SOZ. Widespread scalp HFOs are indicative of a larger epileptic network and associated with poor postsurgical outcome.SignificanceAnalysis of scalp HFO add clinically important information about the extent of epileptic areas during presurgical simultaneous scalp and intracranial EEG recordings. 相似文献
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《Journal of cranio-maxillo-facial surgery》2019,47(10):1551-1556
Fractures through the mandible at the level of the parasymphysis extending obliquely and traversing through the transitional zone to body region are relatively common. Therefore, a surgeon should have an appropriate understanding of the biomechanics of different plating techniques to fix these fractures. There is always a dilemma for the surgeon as to whether to fix these mandibular segments with one or two miniplates, and the presence of mental neurovascular bundle makes it more challenging. A study was planned in the Department of Oral and Maxillofacial Surgery to evaluate a novel twin-fork design of a miniplate used for fracture fixation at the transition zone of parasymphysis and body region of mandible after an in-vitro study of same design, and provided encouraging results. A total of 30 patients (10 patients in three groups each) were included in the study. All patients were evaluated preoperatively and postoperatively for operating time, ease of placement of miniplate, occlusion, reduction of fracture, neurosensory disturbances and infection. The novel design of twin-fork−shaped miniplate proved to be superior to the conventional miniplate in terms of neurosensory (Fisher exact test 17.40; p = 0.003) and functional outcome. There was statistically significant difference (χ2 = 13.895, p = 0.031) in postoperative reduction of fracture at week 4, indicating superiority of the twin-fork miniplate among the other conventional designs. The study concludes that the use of newly designed twin-fork−shaped miniplate should be encouraged in the fractures of transitional zone of parasymphysis-body region involving mental neurovascular bundle. 相似文献
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目的了解丽水市呼吸道病原体感染情况及流行病学特征,为呼吸道传染病诊疗与防控提供科学依据。方法回顾性分析2020年3月至2021年12月丽水市人民医院收治的4035例呼吸道感染患者13项呼吸道病原体PCR毛细电泳核酸检测结果,并分析病原体感染分布特征。结果呼吸道病原体感染患者阳性检出率为32.24%(1301/4035),检出率前5位分别是HRV(16.60%)、HRSV(7.09%)、HPIV(2.87%)、HMPV(2.21%)、HADV(1.96%)。混合感染阳性占比为7.61%(99/1301),Boca病毒(76.0%)与Ch(46.15%)易与其它病原体形成混合感染。不同性别呼吸道病原体感染率差异无统计学意义(P>0.05)。虽然不同季节呼吸道病原体整体感染率差异无统计学意义(P>0.05),但HRV好发于春秋两季,而HPIV在春秋两季感染率较低,春季HRSV感染率较低,HADV在夏秋两季感染率较低,HMPV在冬季较为流行。未成年人呼吸道病原体感染率较高,HRSV、HRV、HPIV、HADV和Boca主要发生于未成年人组,InfB和HMPV在未成年和青年人群感染率都较高。结论未成年人群是呼吸道病原体易感人群,应加强未成年人呼吸道传染病防控。 相似文献
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建立了顶空毛细管GC法测定吉非罗齐中甲酸乙酯、THF和甲基环己烷3种有机溶剂的残留量。采用HP-1毛细管柱,溶剂DMA,内标乙酸乙酯。平均同收率分别为99.8%、100.3%、100.0%,RSD分别为0.71%、1.51%和1.76%。 相似文献