Tomography

体层摄影术
  • 文章类型: Journal Article
    本文对肥料级和颗粒级硝酸铵(V)的形态进行了评估。使用X射线粉末衍射(XRD)分析所有样品,扫描电子显微镜(SEM)和层析成像技术。XRD结果表明,尽管种源不同,所有样品表现出相似的Pmmm对称性和衍射图案。SEM图像表明,与肥料级的对应物相比,颗粒硝酸铵(V)显示出更复杂的外部和内部晶体结构。此外,层析成像分析表明,每个颗粒硝酸铵(V)样品表现出不同的孔隙特征,包括不同的孔径和分布模式。两种方法均证实,横截面中的肥料级硝酸铵(V)具有浮石结构,多孔颗粒硝酸铵(V)具有相当复杂的结构,仅在样品4的情况下观察到中心腔。中心腔的外观可以通过多孔颗粒硝酸铵(V)的不同条件或制造工艺来解释。此外,肥料型硝酸铵(V)的表面积与体积比最低。与多孔型硝酸铵(V)相比,为21%。这个,连同约的最低表面积。116mm2,证实了硝酸铵(V)生产商披露的肥料级硝酸铵(V)的最低吸收能力。
    This paper presents an evaluation of the morphology of fertilizer-grade and prill-grade ammonium nitrate(V). All samples were analyzed using X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and tomography techniques. The XRD results revealed that despite various provenances, all samples exhibited similar Pmmm symmetry and diffraction patterns. SEM images indicated that prill ammonium nitrate(V) showed a more complex external and internal crystal structure than fertilizer-grade counterparts. Furthermore, tomography analysis revealed that each prill ammonium nitrate(V) sample demonstrated distinct porosity characteristics, including varying pore sizes and distribution patterns. Both methods confirmed that fertilizer-grade ammonium nitrate(V) in the cross-section had a pumice structure, and porous prill ammonium nitrate(V) had a rather complex structure, with a central cavity observed only in the case of Sample 4. The appearance of a central cavity can be explained by the different conditions or manufacturing processes of porous prill ammonium nitrate(V). Moreover, the fertilizer-type ammonium nitrate(V) exhibited the lowest surface-to-volume ratio of ca. 21% compared to the porous-type ammonium nitrate(V). This, together with the lowest surface area of ca. 116 mm2, confirmed the lowest absorption capacity of the fertilizer-grade ammonium nitrate(V) disclosed by the ammonium nitrate(V) producer.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    目标:我们的目标是开发一种人工智能(AI)系统,用于使用先进的深度学习来检测计算机断层扫描(CT)图像中的尿路结石,能够实时计算结石参数,例如体积和密度。这对治疗决策至关重要。将系统的性能与急诊室(ER)场景中泌尿科医生的性能进行了比较。
    方法:2022年8月至2023年7月接受结石手术的患者的轴向CT图像包括数据集,分成70%用于培训,10%用于内部验证,20%用于测试。两名泌尿科医生和一名AI专家使用Labelig为地面数据注释了石头。YOLOv4架构用于培训,通过RTX4900图形处理单元(GPU)加速。使用CT图像对100例可疑尿石症患者进行外部验证。
    AI系统在39.433个CT图像上进行了训练,其中9.1%为正。该系统实现了95%的准确度,以1:2的正负样本比率达到峰值。在5736张图像的验证集中(482张阳性),准确率保持在95%。遗漏(2.6%)主要是不规则结石。假阳性(3.4%)通常是由于伪影或钙化。使用来自ER的100张CT图像进行的外部验证显示准确率为94%;错过的病例大多是输尿管膀胱交界处结石,不包括在训练集中。人工智能系统在速度上超过了人类专家,在13秒内分析150张CT图像,而泌尿科医师评估为38.6s,正式阅读为23h。AI系统在0.2s内计算石头体积,与泌尿科医生计算的77秒相比。
    结论:我们的人工智能系统,它使用先进的深度学习,在真实临床环境中协助诊断尿石症的准确率为94%,并具有使用标准消费级GPU进行快速诊断的潜力。
    结果:我们开发了一种新的AI(人工智能)系统,该系统可以在CT(计算机断层扫描)扫描中快速准确地检测肾结石。测试表明,该系统非常有效,急诊科真实病例的准确率为94%。它比传统方法快得多,并提供快速可靠的结果,以帮助医生为患者做出更好的治疗决策。
    OBJECTIVE: Our aim was to develop an artificial intelligence (AI) system for detection of urolithiasis in computed tomography (CT) images using advanced deep learning capable of real-time calculation of stone parameters such as volume and density, which are essential for treatment decisions. The performance of the system was compared to that of urologists in emergency room (ER) scenarios.
    METHODS: Axial CT images for patients who underwent stone surgery between August 2022 and July 2023 comprised the data set, which was divided into 70% for training, 10% for internal validation, and 20% for testing. Two urologists and an AI specialist annotated stones using Labelimg for ground-truth data. The YOLOv4 architecture was used for training, with acceleration via an RTX 4900 graphics processing unit (GPU). External validation was performed using CT images for 100 patients with suspected urolithiasis.
    UNASSIGNED: The AI system was trained on 39 433 CT images, of which 9.1% were positive. The system achieved accuracy of 95%, peaking with a 1:2 positive-to-negative sample ratio. In a validation set of 5736 images (482 positive), accuracy remained at 95%. Misses (2.6%) were mainly irregular stones. False positives (3.4%) were often due to artifacts or calcifications. External validation using 100 CT images from the ER revealed accuracy of 94%; cases that were missed were mostly ureterovesical junction stones, which were not included in the training set. The AI system surpassed human specialists in speed, analyzing 150 CT images in 13 s, versus 38.6 s for evaluation by urologists and 23 h for formal reading. The AI system calculated stone volume in 0.2 s, versus 77 s for calculation by urologists.
    CONCLUSIONS: Our AI system, which uses advanced deep learning, assists in diagnosing urolithiasis with 94% accuracy in real clinical settings and has potential for rapid diagnosis using standard consumer-grade GPUs.
    RESULTS: We developed a new AI (artificial intelligence) system that can quickly and accurately detect kidney stones in CT (computed tomography) scans. Testing showed that this system is highly effective, with accuracy of 94% for real cases in the emergency department. It is much faster than traditional methods and provides rapid and reliable results to help doctors in making better treatment decisions for their patients.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    背景:随着老龄化人口的逐步增加,机会性计算机断层扫描(CT)扫描的使用正在增加,这可能是一种有价值的方法来获取有关老年人群肌肉和骨骼的信息。
    目的:本研究的目的是通过使用椎骨和椎旁肌肉的图像来开发和外部验证基于CT的机会性骨折预测模型。
    方法:这些模型是基于2010年至2019年对1214例腹部CT图像患者的回顾性纵向队列研究而开发的。这些模型在495名患者中进行了外部验证。这项研究的主要结果定义为在5年随访中识别椎骨骨折事件的预测准确性。图像模型是使用注意力卷积神经网络-递归神经网络模型从椎骨和椎旁肌肉的图像开发的。
    结果:开发和验证组中患者的平均年龄分别为73岁和68岁,其中69.1%(839/1214)和78.8%(390/495)是女性,分别。在外部验证队列中,用于预测椎骨骨折的受试者操作员曲线下面积(AUROC)在椎骨和椎旁肌肉图像中优于仅骨骼图像中的面积(分别为0.827,95%CI0.821-0.833和0.815,95%CI0.806-0.824;P<.001)。这些图像模型的AUROC高于骨折风险评估模型(主要骨质疏松风险为0.810,0.780为髋部骨折风险)。对于使用年龄的临床模型,性别,BMI,使用类固醇,吸烟,可能的继发性骨质疏松症,2型糖尿病,艾滋病毒,丙型肝炎,肾功能衰竭,外部验证队列的AUROC值为0.749(95%CI0.736-0.762),低于使用椎骨和肌肉的图像模型(P<0.001)。
    结论:使用椎骨和椎旁肌肉图像的模型比使用仅骨或临床变量图像的模型表现更好。机会性CT筛查可能有助于识别未来骨折风险高的患者。
    BACKGROUND: With the progressive increase in aging populations, the use of opportunistic computed tomography (CT) scanning is increasing, which could be a valuable method for acquiring information on both muscles and bones of aging populations.
    OBJECTIVE: The aim of this study was to develop and externally validate opportunistic CT-based fracture prediction models by using images of vertebral bones and paravertebral muscles.
    METHODS: The models were developed based on a retrospective longitudinal cohort study of 1214 patients with abdominal CT images between 2010 and 2019. The models were externally validated in 495 patients. The primary outcome of this study was defined as the predictive accuracy for identifying vertebral fracture events within a 5-year follow-up. The image models were developed using an attention convolutional neural network-recurrent neural network model from images of the vertebral bone and paravertebral muscles.
    RESULTS: The mean ages of the patients in the development and validation sets were 73 years and 68 years, and 69.1% (839/1214) and 78.8% (390/495) of them were females, respectively. The areas under the receiver operator curve (AUROCs) for predicting vertebral fractures were superior in images of the vertebral bone and paravertebral muscles than those in the bone-only images in the external validation cohort (0.827, 95% CI 0.821-0.833 vs 0.815, 95% CI 0.806-0.824, respectively; P<.001). The AUROCs of these image models were higher than those of the fracture risk assessment models (0.810 for major osteoporotic risk, 0.780 for hip fracture risk). For the clinical model using age, sex, BMI, use of steroids, smoking, possible secondary osteoporosis, type 2 diabetes mellitus, HIV, hepatitis C, and renal failure, the AUROC value in the external validation cohort was 0.749 (95% CI 0.736-0.762), which was lower than that of the image model using vertebral bones and muscles (P<.001).
    CONCLUSIONS: The model using the images of the vertebral bone and paravertebral muscle showed better performance than that using the images of the bone-only or clinical variables. Opportunistic CT screening may contribute to identifying patients with a high fracture risk in the future.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    Although kidney transplantation is the best therapeutic option for patients with chronic kidney disease, the immunosuppression required greatly increases susceptibility to infections that are responsible for high post-transplant mortality. Pulmonary tuberculosis (TB) represents a major cause of such infections, and its early diagnosis is therefore quite important. In view of that, we researched the manifestations of active pulmonary TB in kidney transplant recipients, through chest X-ray and computed tomography (CT), as well as determining the number of cases of active pulmonary TB occurring over a 3.5-year period at our institution. We identified four cases of active pulmonary TB in kidney transplant recipients. The CT scans provided information complementary to the chest X-ray findings in all four of those cases. We compared our CT findings with those reported in the literature. We analyzed our experience in conjunction with an extensive review of the literature that was nevertheless limited because few studies have been carried out in lowand middle-income countries, where the incidence of TB is higher.
    Apesar de o transplante renal ser a melhor opção terapêutica para pacientes com doença renal crônica, a imunodepressão decorrente desse tratamento eleva muito a suscetibilidade desses pacientes a infecções, responsáveis por altas taxas de mortalidade pós-operatórias. A tuberculose (TB) pulmonar é uma significativa causa dessas infecções, sendo muito importante o seu diagnóstico precoce. Assim, nós pesquisamos as manifestações da TB pulmonar ativa nessa população de transplantados renais por meio de radiografias simples e tomografia computadorizada (TC) do tórax, também para estabelecer o número de casos de TB pulmonar ativa em nossa instituição após levantamento de 3,5 anos. Encontramos quatro casos de TB pulmonar ativa em pacientes transplantados renais. A TC forneceu informações adicionais em relação às radiografias de tórax em 100% dos casos analisados. Comparamos os nossos achados de TC com os relatados na literatura. Somamos a experiência obtida com extensa revisão da literatura, ainda limitada nessa questão, com poucos estudos realizados em países em desenvolvimento onde a incidência de TB é maior.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    UNASSIGNED: To conduct a survey on the use of the term \"interstitial lung abnormalities\" in radiology reports in Brazil, propose an appropriate Portuguese-language translation for the term, and provide a brief review of the literature on the topic.
    UNASSIGNED: A survey was sent via electronic message to various radiologists in Brazil, asking about their familiarity with the term, which translation of the term they use in Portuguese, and whether they use the criteria proposed by the Fleischner Society.
    UNASSIGNED: A total of 163 responses were received, from all regions of Brazil. Although the vast majority (88%) of the respondents stated that they were familiar with the term \"interstitial lung abnormalities\", there was considerable variation regarding the equivalent term they used in Portuguese.
    UNASSIGNED: We suggest that the term \"anormalidades pulmonares intersticiais\" be used in order to standardize radiology reports and disseminate knowledge of these findings in Brazil.
    UNASSIGNED: Fazer um levantamento sobre o uso do termo interstitial lung abnormalities nos laudos radiológicos no Brasil, propor uma tradução para o termo e fazer uma breve revisão sobre o tema.
    UNASSIGNED: Foi enviada uma pesquisa, por meio de mensagem eletrônica, para diversos radiologistas de todo o Brasil, questionando sobre a familiarização com o termo, qual tradução em português utilizam e se usam os critérios propostos pela diretriz da Sociedade Fleischner.
    UNASSIGNED: Foram recebidas 163 respostas de todas as regiões do Brasil e a grande maioria dos radiologistas respondeu estar familiarizado com o termo interstitial lung abnormalities (88%), mas houve grande variação em relação ao termo utilizado como tradução para o português.
    UNASSIGNED: Sugerimos a padronização do termo “anormalidades pulmonares intersticiais”, a fim de uniformizar os relatórios radiológicos e difundir esta entidade no País.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    桡骨头骨折的适当管理是不可或缺的,以防止长期后果,如慢性疼痛和运动丧失。先进的成像系统,像显微计算机断层扫描(μCT),对于理解桡骨头骨折模式很有价值,因为它们利用微米级分辨率来定义骨骼健康的重要参数,如皮质密度和小梁厚度。这项研究的目的是利用μCT识别和描述放射状头的结构形态。将九个新鲜冷冻的尸体人体半径分为四个相等的象限,基于,并标记为后内侧,后外侧,前内侧,和前外侧。用SCANCOMicroCT40扫描象限,以36.0μm的分辨率进行皮质和松质骨密度测量。骨密度,直接骨小梁数,和小梁厚度记录为毫克羟基磷灰石/cm3。进行单向重复测量ANOVA以比较骨密度,小梁数,和四个象限中每个象限的小梁厚度(p<0.05)。后内侧象限比其他象限包含更多的骨骼。与前内侧象限(54.6mgHA/cm3)相比,后内侧象限(148.1mgHA/cm3)的骨密度明显更高,后外侧象限(137.5mgHA/cm3)与前内侧象限(54.6mgHA/cm3)相比,和后外侧象限(137.5mgHA/cm3)与前外侧象限(58.1mgHA/cm3)相比。象限之间的小梁数量没有显着差异。与后内侧(0.1809mgHA/cm3)象限相比,前外侧(0.1417mgHA/cm3)和前内侧(0.1416mgHA/cm3)象限的小梁厚度显着降低。与前半部相比,发现radial头的后半部具有更高的圆柱和拱形密度。桡骨远端骨小梁的微结构形成柱状,struts,和拱门,这允许通过骨骼有效地传递应力。桡骨头的微观结构与桡骨远端具有相似的微观结构,本研究确定了桡骨头中存在柱和拱。这些结构,随着小梁密度,在桡骨头后部可以解释较低的发生率涉及桡骨头后半部的骨折。此外,我们的研究支持以下观点:与其他区域相比,前外侧象限的骨折发生率较高是由于微结构特征和相对缺乏支持结构.从这项研究中获得的新颖见解将有助于开发针对预防措施的先进干预措施,并更好地治疗桡骨头骨折,例如当螺钉指向较密集的后内侧象限时,购买更令人满意的购买。
    Appropriate management of radial head fractures is integral to prevent long-term consequences like chronic pain and loss of motion. Advanced imaging systems, like micro-computed tomography (μCT), are valuable for understanding radial head fracture patterns as they utilize micrometer scale resolution to define important parameters of bone health like cortical density and trabecular thickness. The purpose of this study was to identify and describe the structural morphology of the radial head utilizing μCT. Nine fresh-frozen cadaveric human radii were divided into four equal quadrants, based, and labeled as posteromedial, posterolateral, anteromedial, and anterolateral. Quadrants were scanned with a SCANCO MicroCT40 with both cortical and cancellous bone density measurements at a resolution of 36.0 μm. Bone density, direct trabecular number, and trabecular thickness were recorded as milligrams of hydroxyapatite/cm3. A one-way repeated measures ANOVA was performed to compare the bone densities, trabecular number, and trabecular thickness of each of the four quadrants (p < 0.05). The posteromedial quadrant contained substantially more bone than other quadrants. Significantly greater bone densities were found in the posteromedial quadrant (148.1 mg of HA/cm3) compared to the anteromedial quadrant (54.6 mg of HA/cm3), posterolateral quadrant (137.5 mg of HA/cm3) compared to the anteromedial quadrant (54.6 mg of HA/cm3), and posterolateral quadrant (137.5 mg of HA/cm3) compared to the anterolateral quadrant (58.1 mg of HA/cm3). The trabecular number was not significantly different between quadrants. Trabecular thickness was significantly lower in the anterolateral (0.1417 mg of HA/cm3) and anteromedial (0.1416 mg of HA/cm3) quadrants compared to the posteromedial (0.1809 mg of HA/cm3) quadrant. The posterior half of the radial head was found to have a higher density of columns and arches compared to the anterior half. The microstructure of trabecular bone in the distal radius forms columns, struts, and arches, which allow for efficient transmission of stress through the bone. The microstructure of the radial head has similar microarchitecture to the distal radius with the present study identifying the presence of columns and arches in the radial head. These structures, along with trabecular density, in the posterior radial head may explain the lower incidence of fractures involving the posterior half of the radial head. Furthermore, our study supports the idea that the high incidence of fractures involving the anterolateral quadrant is due to microarchitecture characteristics and the relative lack of supportive structures compared to other areas. The novel insight gained from this study will aid in the development of advanced interventions for preventative measures and better treatment of radial head fractures like more satisfactory purchase when screws are directed towards the denser posteromedial quadrant.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    为了确定接受常规治疗的个体中亚临床圆锥角膜(SKCN)的患病率,无并发症的年龄相关性白内障手术及其对视力和屈光结果的影响。
    在美国的一个主要学术眼科,我们回顾了2011年1月至2022年6月接受手术的50岁及以上患者的记录.我们排除了断层摄影数据质量差或不可靠的患者,以前的角膜手术,角膜屈光手术,和显著的视觉限制眼部病理。如果一只眼睛的Belin-Ambrósio增强扩张指数(BAD-D)≥1.7,我们定义了SKCN,这是基于大型研究的荟萃分析结果。除了BAD-D截止,眼睛必须在七个附加参数中的至少一个上发生显着偏离:1)最薄点的后高度,2)垂直不对称指数,3)表面变化指数,4)总前端高阶像差,5)前垂直昏迷,6)前二次垂直昏迷,7)背部垂直昏迷。如果至少一只眼睛符合基于断层摄影术的分类,并且两只眼睛都没有明显的KCN,则个体患有SKCN。视觉和屈光结果数据来自一位经验丰富的白内障外科医生的患者,病例从2021年7月至2022年6月。统计学显著性设定为p<0.05。
    在3828个人的5592只眼睛中,SKCN的患病率为24.7%(95%CI,23.4-26.1,945人),KCN的患病率为1.9%(95%CI,1.6-2.4,87例)。SKCN的患病率不随年龄增长而增加,在女性和非白人种族中更为普遍。术后一个月的中位矫正视力(DCVA)和DCVA改善的眼睛比例在正常和SKCN眼睛之间相似。在正常和SKCN眼之间,屈光目标内达到±0.5和±1.0屈光度的眼睛比例相似。
    SKCN非常普遍,应该检测,但不太可能对常规结局产生重大有害影响,简单的白内障手术.
    UNASSIGNED: To determine the prevalence of subclinical keratoconus (SKCN) among individuals undergoing routine, uncomplicated age-related cataract surgery and its impact on visual and refractive outcomes.
    UNASSIGNED: At a major academic ophthalmology department in the United States, we reviewed records of patients aged 50 years and older who underwent surgery from January 2011 to June 2022. We excluded patients who had poor-quality or unreliable tomographic data, previous corneal surgery, keratorefractive procedures, and significant vision-limiting ocular pathology. We defined SKCN if an eye had a Belin-Ambrósio enhanced ectasia index (BAD-D) ≥1.7, which was based on the results of a meta-analysis of large studies. In addition to the BAD-D cutoff, the eye had to deviate significantly on at least one of seven additional parameters: 1) posterior elevation at thinnest point, 2) index of vertical asymmetry, 3) index of surface variation, 4) total front higher order aberrations, 5) front vertical coma, 6) front secondary vertical coma, 7) back vertical coma. An individual had SKCN if at least one eye met the tomography-based classification and did not have manifest KCN in either eye. Visual and refractive outcomes data were acquired from patients of one experienced cataract surgeon with cases done from July 2021 to June 2022. Statistical significance was set at p < 0.05.
    UNASSIGNED: Among 5592 eyes from 3828 individuals, the prevalence of SKCN was 24.7% (95% CI, 23.4 - 26.1, 945 individuals), and the prevalence of KCN was 1.9% (95% CI, 1.6 - 2.4, 87 individuals). The prevalence of SKCN did not increase with age and was more prevalent among females and non-white races. Median post-operative month one distance-corrected visual acuity (DCVA) and proportion of eyes with improvement in DCVA were similar between normal and SKCN eyes. The proportion of eyes reaching ±0.5 and ±1.0 diopter within the refractive target were similar between normal and SKCN eyes.
    UNASSIGNED: SKCN is highly prevalent and should be detected but is unlikely to have a significant deleterious effect on outcomes in routine, uncomplicated cataract surgery.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Case Reports
    肾上腺外骨髓脂肪瘤(EAM)是一种罕见的良性肿瘤,由成熟的脂肪和造血组织组成。其病因仍有待阐明,很少有病例报道描述中枢神经系统EAM的临床特征和治疗。本研究介绍了我们在右额叶区域EAM病例的临床管理中的经验和实践。在头部计算机断层扫描(CT)上发现一名56岁的妇女患有占位性右额叶病变。未增强的磁共振成像(MRI)显示约1.5x1.2cm的病变。全腹增强CT显示右侧骶前肿块,直径2.0厘米,有明显的利润。术后组织病理学发现主要为成熟脂肪组织混合髓外造血成分。这证实了(骨)骨髓脂肪瘤的诊断。中枢神经系统髓质脂肪瘤极为罕见。据作者所知,只有两例颅内髓脂肪瘤被报道,本研究介绍了第一例以英语报道的中国患者。然而,当CT显示高密度和MRI显示混合密度在肿瘤区域,即使没有增强,在鉴别诊断中应考虑髓脂肪瘤的可能性。
    Extra-adrenal myelolipoma (EAM) is a rare benign tumor composed of mature adipose and hematopoietic tissues. Its etiology remains to be elucidated and there are few case reports describing the clinical features and treatment of EAMs in the central nervous system. The present study presented our experience and practice in the clinical management of a case of EAM in the right frontal region. A 56-year-old woman was found to have a space-occupying right frontal lesion on computed tomography (CT) of the head. Unenhanced magnetic resonance imaging (MRI) showed a lesion of ~1.5x1.2 cm. Enhanced whole abdominal CT showed a right presacral mass, 2.0 cm in diameter, with clear margins. The postoperative histopathological findings showed mainly mature adipose tissue mixed with extramedullary hematopoietic components. This confirmed the diagnosis of a (bone) marrow lipoma. Myelolipoma of the central nervous system is extremely rare. to the best of the authors\' knowledge, only two cases of intracranial myelolipoma have been reported, and the present study introduced the first case in a Chinese patient reported in English. However, when CT shows high density and MRI shows mixed density in the tumor area even without enhancement, the possibility of myelolipoma should be considered in the differential diagnosis.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    介绍先天性感觉神经性听力损失(CSNHL)研究的途径之一是尝试通过使用高分辨率计算机断层扫描(CT)扫描进行内耳评估来表征其病因。有轻微畸形,简单的视觉检查并不总是可以识别内耳的结构是否正常。目的验证内耳的测量是否可以预测感觉神经性听力损失(SNHL),并建议尺寸限制的截止点。方法回顾性横断面研究214例患者的内耳CT扫描测量,50例先天性SNHL(CSNHL)和164例获得性SNHL(ASNHL)(对照组)。结果在CSNHL组中,中央骨岛(CBI)小0.48毫米(p<0.001),耳蜗神经孔径(CNA)小0.10mm(p<0.001),耳蜗高度(CH)小0.15mm(p<0.001)。各组前庭水管(VA)和耳蜗宽度(CW)相似(0.70vs0.72,p=0.19,7.20vs7.15p=0.23)。CSNHL的预测截止点为CBI=3.6mm,CAN=1.4mm,CH=3.4mm,CW=7.0mm,和VA=0.9毫米。结论先天性感觉神经性听力损失决定了CBI的减少,耳蜗神经(OCN)的开放,和CW。因此,这些措施,在所示的截止点,应该让我们了解先天性耳聋的诊断。
    Introduction  One of the paths in the investigation of congenital sensorineural hearing loss (CSNHL) is to try to characterize its etiology through the inner ear evaluation using high resolution computer tomography (CT) scans. With minor malformation, it is not always possible for a simple visual inspection to recognize if the structure in the inner ear is normal or not. Objective  To verify if measurements of the inner ear are predictive of sensorineural hearing loss (SNHL) and suggest cutoff points of size limits. Methods  Retrospective cross-sectional study of inner ear CT scan measurements of 214 patients, 50 with congenital SNHL (CSNHL) and 164 acquired SNHL (ASNHL) (control group). Results  In the CSNHL group, central bony island (CBI) were 0.48 mm smaller ( p  < 0.001), cochlear nerve aperture was (CNA) 0.10 mm smaller ( p  < 0.001), and cochlea height was (CH) 0.15 mm smaller ( p  < 0.001). Vestibular aqueduct (VA) and cochlea width (CW) were similar between groups (0.70 vs 0.72, p  = 0.19, and 7.20 vs 7.15 p  = 0.23). The predictive cutoff points for CSNHL were CBI = 3.6 mm, CAN = 1.4 mm, CH = 3.4 mm, CW = 7.0 mm, and VA = 0.9 mm. Conclusion  Congenital sensorineural hearing loss determined a decrease in CBI, opening of the cochlear nerve (OCN), and CW. Thus, these measures, at the cutoff points indicated, should make us aware of the diagnosis of congenital hearing loss.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    原子探针断层扫描(APT)已用于研究两种模型硼硅酸盐玻璃的微观结构,这些玻璃旨在了解五氧化二磷(P2O5)的溶解度极限。该成分存在于某些用于玻璃化的高放射性国防废物中,其中相分离可能导致许多与玻璃加工及其长期化学和结构稳定性有关的问题。初步确定了合适的聚焦离子束(FIB)制备路线和APT分析条件,在检查它们详细的微观结构之前。在3.0摩尔%P2O5掺杂玻璃中,APT数据的视觉检查和敏感统计分析均显示出均匀的微观结构,将含量提高到4.0mol%时,会引发富集磷的纳米级沉淀物的形成。这项研究证实了这些玻璃的预期不均匀性和相分离,并提供了使用APT以近原子尺度分辨率表征这些玻璃的途径。
    Atom probe tomography (APT) has been utilized to investigate the microstructure of two model borosilicate glasses designed to understand the solubility limits of phosphorous pentoxide (P2O5). This component is found in certain high-level radioactive defence wastes destined for vitrification, where phase separation can potentially lead to a number of issues relating to the processing of the glass and its long-term chemical and structural stability. The development of suitable focused ion beam (FIB)-preparation routes and APT analysis conditions were initially determined for the model glasses, before examining their detailed microstructures. In a 3.0 mol% P2O5-doped glass, both visual inspection and sensitive statistical analysis of the APT data show homogeneous microstructures, while raising the content to 4.0 mol% initiates the formation of phosphorus-enriched nanoscale precipitates. This study confirms the expected inhomogeneities and phase separation of these glasses and offers routes to characterizing these at near-atomic scale resolution using APT.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

公众号