颅内三叉神经瘤的CT及MRI影像分析及诊断

目的：通过分析颅内三叉神经瘤的CT和MRI影像表现，探讨三叉神经瘤的影像学特点及鉴别诊断。方法：回顾性分析15例手术后病理证实的颅内三叉神经瘤的CT和MR资料。结果：肿瘤多数位于中颅窝及后颅窝，少数可骑跨于中、后颅窝，呈类圆形或圆形伴乳头状突起，累及Meckel腔，骑跨者多呈哑铃状，少数形状极不规则。肿瘤内多数伴有囊变。结论：颅内三叉神经瘤的CT和MRI表现及其部位、形态具有一定的特征性，结合其影像学表现和临床资料多可作出正确诊断。     

肾上腺疾病的影像诊断与鉴别诊断

目的：提高对肾上腺疾病的影像诊断水平,方法：收集1993年1月－1999年9月经MRI检查的151例疑继发性高血压病人中有完整住院资料的46例临床,MRI,CT,B超及实验室结果,按病因分为肾上腺腺病（11例）,嗜铬细胞瘤（11例）,皮质腺癌（7例）,肾上腺增生（17例）共4组,结果：（1）大小：腺瘤体积小（原发性醛固酮增多症小于3cm,柯兴综合征小于5cm),嗜铬细胞瘤大于3cm,增生0．6－3．5cm.（2）质地：腺瘤和增生质地均匀,呈等T1,等T2信号,CT值15－25H嗜铬细胞瘤和腺癌易出血坏死液化。（3）实验室检查,原醛通常高钠低钾血症,嗜铬细胞瘤和腺癌患者尿中VMA可呈阳性,（4）肾上腺增生大小,形态及生化结果多种多样。结论：影像检查有利于明上腺疾病的检出,结合临床及实验室检查可提高病变的定性诊断。     

磁共振成像和CT影像检查在老年多发性脑梗死诊断中的对比研究

目的 对比分析老年多发性脑梗死临床诊断中MRI和CT影像检查的应用价值.方法 以2018年2月至2019年12月间在本院诊疗的114例老年多发性脑梗死患者为对象,均予以MRI和CT影像检查,对比分析两种技术在不同发病时间、不同梗死部位患者中的诊断结果.结果 病程<24 h、病程24～72 h的患者,MRI技术的检出率分...     

骨质疏松与恶性骨质破坏致椎体压缩性骨折的CT磁共振成像影像特点及鉴别诊断

目的 探究采用CT、磁共振成像(MRI)鉴别诊断骨质疏松与恶性骨破坏导致的椎体压缩性骨折的临床疗效.方法 选择2019年12月至2020年12月经临床诊疗证实为骨质疏松及恶性骨质破坏致脊椎骨折的患者76例,分为2组:A组(骨质疏松改变并伴有压缩性骨折,36例),B组(恶性骨破坏致压缩性骨折,40例).对比2组患者椎体、...     

综合影像诊断同侧融合肾2例

1病例简介病例1患者,男,20岁。因发作性右腹部酸痛不适半月余入院,查体无阳性体征发现。超声检查:左肾窝未见肾脏回声,右侧腹可探及两个肾脏回声,呈上下排列,其上方为右肾,大小形态正常,约11.6cm×4.4cm×5.4cm,肾实质厚1.2cm,回声均匀,集合系统不分离;下方为左肾,其上极与右肾下极相连接,约10.2cm×4.1cm×5.0cm,肾实质变薄,厚度0.8cm,肾盏扩张,肾盂分离(图1)。CDFI:右肾内显示血流信号较丰富,左肾内血流信号减少。超声诊断:同侧融合肾并左肾重度积水。MRI示:左肾区未见肾脏形态,于髂总动脉分叉处见体积较小左肾,该肾向右侧跨越中线与右…     

全身MRI/DWI影像融合恶性肿瘤检出的诊断正确性与PET/CT的对照性研究

目的与PET/CT对照,前瞻性评价全身T2加权(wbT2)、全身扩散加权成像(wbDWI)与wbT2/wbDWI融合影像对恶性肿瘤检出的诊断正确性。方法 64例病人[男44例,     

脊柱结核的影像诊断及鉴别诊断

脊柱结核多发生于儿童及青壮年，是较严重的骨关节疾病，近年来发病率有上升趋势。治疗不及时可导致椎体的严重破坏及神经损伤。收集3个月-2年经CT复查、临床观察及病理证实的20例脊柱结核，对其CT及MRI表现进行分析，以提高对本病的认识。     

鼻咽癌放射治疗定位的CT/MRI图像配准辅助装置的研究

目的 研制用于鼻咽癌放射治疗定位的CT/MRI图像配准辅助装置,并且通过组织勾画差异分析使用该装置后所得配准融合图像在临床中的应用意义。方法 在普通的磁共振头颈线圈中设计特定形状的头枕,保持患者在扫描时与CT定位扫描时相同的体位。采用配对t检验分析CT图像与融合图像中腮腺、下颌骨的勾画差异。结果 患者的头颈部CT、MRI图像的配准精度较未使用该装置的图像具有明显的提高,使用该配准图像得到的融合图像、组织结构位置、细节显示准确清晰。左右腮腺体积在CT图像中较CT/MRI融合图像中偏小,左腮腺体积融合和CT图像中的体积分别为（17.78±6.89）cm³和（17.17±7.02）cm³（t=-2.715,P<0.05）;右腮腺体积融合和CT图像中的体积分别为（19.23±8.91）cm³和（17.47±7.42）cm³（t=-2.552,P<0.05）;下颌骨在CT图像中勾画体积较CT/MRI融合图像偏大,左下颌骨体积融合和CT图像中的体积分别为（33.7±5.59）cm³和（34.8±6.27）cm³（t=3.548,P<0.05）;右下颌骨体积融合和CT图像中的体积分别为（34.46±6.08）cm³和（35.38±6.72）cm³（t=3.14,P<0.05）。结论 使用该辅助装置,可以得到头颈部配准融合准确的CT/ MRI的图像,此融合图像对临床医师的组织和病灶勾画具有积极的参考价值。     

Direct quantitative in vivo comparison of calcified atherosclerotic plaque on vascular MRI and CT by multimodality image registration

PURPOSE: To investigate direct volumetric in vivo correspondence of calcified atherosclerotic plaque lesions in MRI and CT images of the thoracic aorta by multimodality image registration and fusion. MATERIALS AND METHODS: Twelve CT (11 noncontrast and one contrast) and MRI (TruFISP, contrast T1-weighted volumetric interpolated breath-hold examination (VIBE)) data sets were co-registered by approximate segmentation of the aorta and subsequent automatic co-registration by maximization of mutual information (MI). We quantitatively assessed 22 co-registered calcified plaque lesions on CT and MRI. RESULTS: The three-dimensional registration consistency and accuracy were 1.74 +/- 1.3 mm, and 2.42 +/- 1.65 mm, respectively. The ratio of CT/MRI calcified plaque volume decreased asymptotically with MRI volume, and correlated with average CT lesion density (r = 0.72) for small lesions (<25 mm(3)). The average calcified plaque volume, circumferential extent, and maximal radial width by MRI were significantly smaller compared to CT (35%, 68%, and 53%, respectively; P < 0.05). CONCLUSION: Software co-registration allowed precise, direct, and voxel-based comparison of calcified atherosclerotic plaque lesions imaged by MRI and CT. In comparison with co-registered MRI, overestimation of calcified plaque in aortic CT due to "blooming" correlates with the average lesion density for small plaques, and is greater for small plaques.     

医学图像融合的临床应用与新进展

医学图像融合是医学图像后处理的研究热点,它充分利用多模态图像,获得互补信息,使临床的诊断和治疗更加准确完善。本文综述了近年来医学图像融合研究的临床应用与最新进展,认为多模态医学图像融合是一个发展趋势,在临床疾病的早期诊断、治疗定位中将发挥重要的作用。     

Clinical evaluation of an MRI-to-ultrasound deformable image registration algorithm for prostate brachytherapy

Purpose

Identifying dominant intraprostatic lesions (DILs) on transrectal ultrasound (TRUS) images during prostate high-dose-rate brachytherapy (HDR-BT) treatment planning is challenging. Multiparametric MRI (mpMRI) is the tool of choice for DIL identification; however, the geometry of the prostate on mpMRI and on the TRUS may differ significantly, requiring image registration. This study evaluates the efficacy of an in-house software for MRI-to-TRUS DIL registration (MR2US) and compares its results to rigid and B-Spline deformable registration.

A graphical user interface for automatic image registration software designed for radiotherapy treatment planning

Medical imaging forms a vital component of radiotherapy treatment planning and its evaluation. The integration of the useful data obtained from multiple imaging modalities for radiotherapy planning is achieved by image registration softwares. In radiotherapy planning systems, normally the computed tomography (CT) slices are kept as a standard upon which other modality images (magnetic resonance imaging [MRI], single photon emission computed tomography [SPECT], positron emission tomography [PET], etc.) are aligned—automatically or interactively. Following validation of successful registration, they are resampled and reformatted, as per the requirements. This paper defines the minimum requirements of automatic image registration software for 3-dimensional (3D) radiotherapy planning and describes the implementation of a suitable graphical user interface developed in Visual Basic (version 5). The automatic image registration (AIR) routines freely available from Dr. Roger P. Woods, UCLA, (USA) were used in this software. This software could be easily implemented and was easy to use for image processing suitable for radiotherapy planning systems.     

A graphical user interface for automatic image registration software designed for radiotherapy treatment planning

Medical imaging forms a vital component of radiotherapy treatment planning and its evaluation. The integration of the useful data obtained from multiple imaging modalities for radiotherapy planning is achieved by image registration softwares. In radiotherapy planning systems, normally the computed tomography (CT) slices are kept as a standard upon which other modality images (magnetic resonance imaging [MRI], single photon emission computed tomography [SPECT], positron emission tomography [PET], etc.) are aligned—automatically or interactively. Following validation of successful registration, they are resampled and reformatted, as per the requirements. This paper defines the minimum requirements of automatic image registration software for 3-dimensional (3D) radiotherapy planning and describes the implementation of a suitable graphical user interface developed in Visual Basic (version 5). The automatic image registration (AIR) routines freely available from Dr. Roger P. Woods, UCLA, (USA) were used in this software. This software could be easily implemented and was easy to use for image processing suitable for radiotherapy planning systems.     

Joint registration and segmentation of neuroanatomic structures from brain MRI

RATIONALE AND OBJECTIVES: Segmentation of anatomic structures from magnetic resonance brain scans can be a daunting task because of large inhomogeneities in image intensities across an image and possible lack of precisely defined shape boundaries for certain anatomical structures. One approach that has been quite popular in the recent past for these situations is the atlas-based segmentation. The atlas, once constructed, can be used as a template and can be registered nonrigidly to the image being segmented thereby achieving the desired segmentation. The goal of our study is to segment these structures with a registration assisted image segmentation technique. MATERIALS AND METHODS: We present a novel variational formulation of the registration assisted image segmentation problem which leads to solving a coupled set of nonlinear Partial Differential Equations (PDEs) that are solved using efficient numeric schemes. Our work is a departure from earlier methods in that we can simultaneously register and segment in three dimensions and easily cope with situations where the source (atlas) and target images have very distinct intensity distributions. RESULTS: We present several examples (20) on synthetic and (3) real data sets along with quantitative accuracy estimates of the registration in the synthetic data case. CONCLUSION: The proposed atlas-based segmentation technique is capable of simultaneously achieve the nonrigid registration and the segmentation; unlike previous methods of solution for this problem, our algorithm can accommodate for image pairs having very distinct intensity distributions.     

Computer-aided evaluation of anatomical accuracy of image fusion between X-ray CT and SPECT

Hybrid scanners, which enable the performance of single photon emission computed tomography (SPECT) and X-ray computed tomography (CT) in one imaging session, have considerable diagnostic potential. However, evaluating the anatomical accuracy of image fusion inherent to these systems remains a challenge. This paper proposes a method for evaluating this variable with minimum user interaction. It focuses on measuring the distance between the centers of gravity of the SPECT hot spot and its counterpart in the CT image. A localized maximally stable extremal regions method is proposed to automatically segment SPECT hot spots, while the corresponding CT structures are segmented by the semi-automatic random walk method, based on a fast multigrid solver. Accuracy and reproducibility of the validation method have been preliminary confirmed by the test with 21 clinical data-sets.     

The impact of image fusion in resolving discrepant findings between FDG-PET and MRI/CT in patients with gynaecological cancers

This study was performed to prospectively investigate the impact of image fusion in resolving discrepant findings between fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and magnetic resonance imaging (MRI) or X-ray computed tomography (CT) in patients with gynaecological cancers. Discrepant findings were defined as lesions where the difference between the FDG-PET and MRI/CT images was assigned a value of at least 2 on a 5-point probability scale. The FDG-PET and MRI/CT images were taken within 1 month of each other. Image fusion between FDG-PET and CT was performed by automatic registration between the two images. During an 18-month period, 34 malignant lesions and seven benign lesions from 32 patients who had undergone either surgical excision or a CT-guided histopathological investigation were included for analysis. Among these cases, image fusion was most frequently required to determine the nature and/or the extent of abdominal and pelvic lesions (28/41, 68%), especially as regards peritoneal seeding (8/41, 20%). Image fusion was most useful in providing better localisation for biopsy (16/41, 39%) and in discriminating between lesions with pathological versus physiological FDG uptake (12/41, 29%). Image fusion changed the original diagnosis based on MRI/CT alone in 9/41 lesions (22%), and the original diagnosis based on FDG-PET alone in 5/41 lesions (12%). It led to alteration of treatment planning (surgery or radiotherapy) in seven of the 32 patients (22%). In patients with gynaecological cancers, the technique of image fusion is helpful in discriminating the nature of FDG-avid lesions, in effectively localising lesions for CT-guided biopsy and in providing better surgical or radiotherapy planning.