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1.
蓝英勇 《医学信息》2018,(7):150-152
目的 探讨三维时间飞跃法磁共振血管成像(3D-TOF-MRA)与数字减影血管造影(DSA)诊断颅内动脉瘤的研究价值。方法 收集20例经DSA及手术确诊为颅内动脉瘤患者,术前均行MRA及DSA检查。MRA检查后经MRP、MIP及VR法重建并与DSA结果进行对比。结果 20例患者DSA检查出23个动脉瘤,MRA VR重建检查出21个动脉瘤,检出率为91.30%,MPR及MIP检查出20个,检出率为87.00%。结论 1.5T 3D-TOF-MRA对颅内动脉瘤有较高的敏感性和准确性,为临床诊断及治疗提供了详细的参考价值,但对于微小动脉瘤存在一定的漏诊现象,应选择DSA进行进一步检查。  相似文献   

2.
PurposeThis study aimed to investigate whether a deep learning model for automated detection of unruptured intracranial aneurysms on time-of-flight (TOF) magnetic resonance angiography (MRA) can achieve a target diagnostic performance comparable to that of human radiologists for approval from the Korean Ministry of Food and Drug Safety as an artificial intelligence-applied software.Materials and MethodsIn this single-center, retrospective, confirmatory clinical trial, the diagnostic performance of the model was evaluated in a predetermined test set. After sample size estimation, the test set consisted of 135 aneurysm-containing examinations with 168 intracranial aneurysms and 197 aneurysm-free examinations. The target sensitivity and specificity were set as 87% and 92%, respectively. The patient-wise sensitivity and specificity of the model were analyzed. Moreover, the lesion-wise sensitivity and false-positive detection rate per case were also investigated.ResultsThe sensitivity and specificity of the model were 91.11% [95% confidence interval (CI): 84.99, 95.32] and 93.91% (95% CI: 89.60, 96.81), respectively, which met the target performance values. The lesion-wise sensitivity was 92.26%. The overall false-positive detection rate per case was 0.123. Of the 168 aneurysms, 13 aneurysms from 12 examinations were missed by the model.ConclusionThe present deep learning model for automated detection of unruptured intracranial aneurysms on TOF MRA achieved the target diagnostic performance comparable to that of human radiologists. With high standalone performance, this model may be useful for accurate and efficient diagnosis of intracranial aneurysm.  相似文献   

3.
We have improved a computerized scheme for the detection of intracranial aneurysms for three-dimensional (3-D) magnetic resonance angiography (MRA) by the use of image features of small protrusions extracted based on a shape-based difference image (SBDI) technique. Initial candidates were identified by use of a multiple gray-level thresholding technique in dot enhanced images, and by finding short branches in skeleton images. Image features related to aneurysms were determined based on candidate regions segmented by use of a region growing technique. For extracting additional features on small protrusions or small aneurysms, we have developed an SBDI technique, which was based on the shape-based difference between an original segmented vessel and a vessel with suppressed local change in thickness. The SBDI technique was useful for obtaining local changes in vessel thickness, i.e., SBD regions, which could be small aneurysms in the case of true positives, but thin or very small regions in the case of false positives. Many false positives were removed by means of rule-based schemes and linear discriminant analysis on various 3-D localized image features, including SBDI features. We tested the computerized scheme on 53 cases with 61 aneurysms and 62 nonaneurysm cases based on a leave-one-out-by-patient test method. As a result, false positives per patient decreased from 5.8 to 3.8, while a high sensitivity of 97% was maintained by use of the SBDI technique, in which SBDI features were effective for removing some false positives. The computer-aided diagnostic (CAD) scheme may be robust and useful in assisting radiologists in the detection of intracranial aneurysms for MRA.  相似文献   

4.
In utero transmission of external and maternal sounds has been studied in pregnant women and in an animal model of human species, the sheep. These works, especially the most recent ones, suggest that local and environmental factors interfere in such a way that signals are attenuated in a complex manner as frequency increases. The present work investigated whether a plain rubber sphere which was filled with water could be considered as a reliable nonbiological model in a study describing the characteristics of sound transmission. A sweeping pure tone, presented externally, was measured inside the rubber sphere using a high signal-to-noise ratio experimental hydrophone. A paradigmatic three components curve was observed between 100 and 20,000 Hz. In the first component of the curve (low to midfrequencies between 100 and 1,000 Hz), the intensity of the inside signal remained stable. The second component of the curve was composed of higher frequencies with the inside pressure falling gradually, demonstrating attenuation of the external signal. The third component of the curve appeared above a critical frequency, the value of which depended on several model and environment parameters. In this component, a series of rapid peaks and drops of the inside high frequency pressure was observed, indicating the presence of resonance systems. Analyses were carried out on the effects of several acoustical parameters, including: the size of the sphere, the location of the hydrophone in the sphere, the distance between the signal source and the hydrophone, the location of the external reference microphone, and the acoustical structure of the environment. These parameters allowed for the definition of their respective roles in the in-utero transmission of external sounds. These data were then compared with measurements performed within a biological model—ewes—under close acoustical settings. The comparisons confirmed the validity of the measurements, suggesting that the model may be useful in studies of sound transmission in utero. © 1998 John Wiley & Sons, Inc. Dev Psychobiol 33: 203–219, 1998  相似文献   

5.
Prompt diagnosis and therapy of aneurysms are critical for patients with nontraumatic subarachnoid hemorrhage (SAH). The aim of our study was to assess the clinical usefulness of multislice computed tomography angiography (CTA) in the surgical and endovascular treatment of intracranial aneurysms. A total of 195 cases with 206 intracranial aneurysms underwent CTA. Fifty (24%) aneurysms underwent surgical clipping while 156 (76%) aneurysms underwent endovascular coiling. In the five missed aneurysms at digital substraction angiography and the nine aneurysms with mass intracerebral hematomas, surgical treatment was successfully performed based on 16-slice CTA alone, and the other 36 aneurysms were clipped on the main basis of the CTA. The intraoperative findings correlated well with the CTA findings and all aneurysms were clipped successfully. Sixteen-slice CTA image information has been shown to determine the choice of aneurysm therapy and assist the surgical and endovascular treatment of intracranial aneurysms.  相似文献   

6.
Neurofibromatosis type 1 (NF1) is often mentioned among the heritable connective tissue disorders associated with intracranial aneurysms, but the association has not been firmly established. We therefore reviewed a contemporary series of hospitalized patients with NF1, many of whom underwent brain magnetic resonance imaging (MRI). We identified patients with NF1 who were hospitalized at Cedars-Sinai Medical Center, Los Angeles, California, between January 1, 1997 and December 31, 2001 through the hospital's centralized medical records system using DRG codes. The mean age of the 39 patients was 30.4 years, and 22 patients had undergone MRI of the brain for the evaluation of symptoms due to the presence of central or peripheral nervous system tumors. Incidental intracranial aneurysms were detected in 2 (5%) of the 39 patients. Limiting the patient population to the 22 patients who had undergone MRI examination, the detection rate was 9%. This was significantly (P < 0.005) higher than the aneurysm detection rate in a control population (0/526 [0%]) of patients hospitalized for primary or secondary brain tumors, all of whom had undergone MRI examination. Our study suggests that patients with NF1 are at an increased risk of developing intracranial aneurysms.  相似文献   

7.
Intracranial aneurysms represent a significant cause of morbidity and mortality. While the risk factors for aneurysm formation are known, the detection of aneurysms remains challenging. Magnetic resonance angiography (MRA) has recently emerged as a useful non-invasive method for aneurysm detection. However, even for experienced neuroradiologists, the sensitivity to small (<5 mm) aneurysms in MRA images is poor, on the order of 30~60% in recent, large series. We describe a fully automated computer-aided detection (CAD) scheme for detecting aneurysms on 3D time-of-flight (TOF) MRA images. The scheme locates points of interest (POIs) on individual MRA datasets by combining two complementary techniques. The first technique segments the intracranial arteries automatically and finds POIs from the segmented vessels. The second technique identifies POIs directly from the raw, unsegmented image dataset. This latter technique is useful in cases of incomplete segmentation. Following a series of feature calculations, a small fraction of POIs are retained as candidate aneurysms from the collected POIs according to predetermined rules. The CAD scheme was evaluated on 287 datasets containing 147 aneurysms that were verified with digital subtraction angiography, the accepted standard of reference for aneurysm detection. For two different operating points, the CAD scheme achieved a sensitivity of 80% (71% for aneurysms less than 5 mm) with three mean false positives per case, and 95% (91% for aneurysms less than 5 mm) with nine mean false positives per case. In conclusion, the CAD scheme showed good accuracy and may have application in improving the sensitivity of aneurysm detection on MR images.  相似文献   

8.
Kissing aneurysms are unusual and relatively rare types of multiple intracranial arterial aneurysms. When located on the anterior communicating artery (ACoA), kissing aneurysms pose considerable diagnostic difficulty on preoperative conventional angiogram. Special angiographic views or 3D rotational angiogram are needed to make the correct diagnosis and to avoid interpreting them as multilobed or bilobed saccular aneurysms on preoperative conventional angiogram. Treatment of these aneurysms, either by clipping or coiling, needs to be individualized. Unique problems which need to be addressed during surgical clipping are high risk of rupture due to dense adhesions between the kissing aneurysms, requirement of at least two clips in a narrow working area, the aneurysm that needs to be clipped first and interference of the first clip with application of subsequent clips. The authors present a case of a 63-year-old male who had kissing ACoA aneurysms managed successfully by clipping.  相似文献   

9.
Cognitive anticipation of a stimulus has been associated with an ERP called "stimulus preceding negativity" (SPN). A new auditory delay task without stimulus-related motor activity demonstrated a prefrontal SPN, present during attentive anticipation of sounds with closed eyes, but absent during distraction of attention and during attention with fixed gaze. ERP maxima found near the eyes required examination of eye movement interference, wherefore six monopolar EOG electrodes were included. Similarities between ERPs and potentials evoked by voluntary eye movements with respect to spatial distribution and polarities of amplitudes around the eyes and over the frontal cortex suggested that, in the closed-eyes condition, small involuntary downward eye movements occurred during attentive anticipation of sounds. Analyses of single trials corroborated this interpretation. On this basis it is suggested that the SPN was caused by such eye movements.  相似文献   

10.
BACKGROUND: Genetic factors are likely to be involved in the pathogenesis of intracranial, ascending thoracic aorta, and infrarenal aortic abdominal aneurysms. Common genetic risk factors for these three types of aneurysms have been suggested. This review describes the results of whole-genome linkage studies on intracranial, thoracic aorta, and aortic abdominal aneurysms, and compares the genomic loci identified in these studies in search of possible common genetic risk factors for the three aneurysmal types. METHODS: A literature search of all whole-genome linkage studies performed on intracranial, thoracic aorta, and aortic abdominal aneurysms was performed. The genomic loci identified in these studies were described and compared in search of similarities between them. RESULTS: Five chromosomal regions on 3p24-25, 4q32-34, 5q, 11q24, and 19q that may play a role in the pathogenesis of two or more aneurysmal types were identified: 3p24-25 for thoracic aorta and intracranial aneurysms; 4q32-34 for aortic abdominal and intracranial aneurysms; 5q for thoracic aorta and intracranial aneurysms; 11q24 for thoracic aorta, aortic abdominal, and intracranial aneurysms; and 19q for aortic abdominal and intracranial aneurysms. CONCLUSIONS: Five chromosomal regions that may include common genetic factors for intracranial, thoracic aorta, and aortic abdominal aneurysms were identified. Further studies are needed to explore these chromosomal regions in different aneurysm patient groups and may further help to unravel the disease pathogenesis of aneurysms in general.  相似文献   

11.
目的利用数字减影血管造影(DSA)旋转三维成像(3D-DSA)与三维256层螺旋CT血管造影对比(3D-CTA).探索其对颅内动脉瘤(AN)(尤其是直径〈3mm的微小AN)的探测能力有无进一步的提高.以及3D-CTA与3D-DSA不同技术之间的对颅内AN检出率的一致性分析。方法临床表现高度怀疑为AN或磁共振血管造影(MRA)怀疑为AN56例患者.其中男性31例,女性25例;年龄38~78岁,平均年龄49岁。全部行头颈联合3D-CTA及3D-DSA检查:由2名影像医师盲法独立判读CTA图像,由1名神经介入医师和1名介入影像医师共同判读3D-DSA图像。以3D-DSA为“金标准”,评估3D-CTA的灵敏度、特异度及不同技术之间的一致性。结果3D-DSA在56例患者中的47例共检出59个AN病灶.其余9例未发现AN。3D-CTA检出AN54个,灵敏度为93-20%~94.90%(均值94.05%),特异度为81.8%。100.0%(均值90.9%):对于AN病灶直径〈3mm,3D-CTA的灵敏度和特异度均值分别为86_4%和95.0%。对AN的检出.3D-CTA判读者之间及3D-CTA与3D-DSA不同技术之间一致性均为优(分别为K=0.847,均值K=0.802):对于AN瘤体最大径的测量。3D-CTA判读者之间及3D-CTA与3D-DSA间差异均无统计学意义(P〉0.05)。结论3D-256层螺旋CTA对直径〈3mm的微小AN灵敏度和特异度均有所提高,判读者之间及与3D-DSA之间的一致性较高,可以作为疑似AN患者的首选筛查方法。两者联合可提高AN的检出率.为介入治疗AN提供可靠的影像学依据。  相似文献   

12.
Genetic and environmental factors play roles in the aetiology of ruptured intracranial aneurysms. Hypertension has been reported as a risk factor for intracranial aneurysm haemorrhage. We have tested if genotypes at the angiotensin converting enzyme (ACE) gene locus are associated with ruptured intracranial aneurysms. The insertion/deletion polymorphism in the ACE gene was genotyped in 258 subjects presenting in East Anglia with ruptured intracranial aneurysms (confirmed at surgery or angiographically) and 299 controls from the same region. ACE allele frequencies were significantly different in the cases and the controls (alleles χ21=4.67, p=0.03). The I allele was associated with aneurysm risk (odds ratio for I allele v D allele = 1.3 (95% CI=1.02-1-65); odds ratio for II v DD genotype = 1.67 (95% CI=1.04-2.66)). The I allele at the ACE locus is over-represented in subjects with ruptured intracranial aneurysms. These data are supported by non-significant trends in the same direction in two previous smaller studies. Thus, this allele may be associated with risk for ruptured intracranial aneurysms.


Keywords: ACE I allele; ruptured intracranial aneurysms  相似文献   

13.
Despite the catastrophic consequence of ruptured intracranial aneurysms, very little is understood regarding their pathogenesis, and there are no reliable predictive markers for identifying at-risk individuals. Few studies have addressed the molecular pathological basis and mechanisms of intracranial aneurysm formation, growth, and rupture. The pathogenesis and rupture of cerebral aneurysms have been associated with inflammatory processes, and these have been implicated in the digestion and breakdown of vascular wall matrix. Epidemiological data indicate that the risk of cerebral aneurysm pathogenesis and rupture in women rises during and after menopause as compared to premenopausal women, and has been attributed to hormonal factors. Moreover, experimental evidence supports a role for estrogen in the modulation of each phase of the inflammatory response implicated in cerebral aneurysm pathogenesis and rupture. While the risk of aneurysm rupture in men also increases with age, this increased risk has been attributed to other recognized risk factors including cigarette smoking, use of alcohol, and history of hypertension, all of which are more common in men than women. We hypothesize, therefore, that decreases in both circulating estrogen levels and cerebrovascular estrogen receptor density may contribute to an increased risk of cerebral aneurysm pathogenesis and rupture in women during and after menopause. To test our hypothesis, experiments are needed to identify genes regulated by estrogen and to evaluate gene expression and intracellular mechanisms in cells/tissues exposed to varying concentrations and duration of treatment with estrogen, metabolites of estrogen, and selective estrogen receptor modulators (SERMs). Furthermore, it is not likely that the regulation of cerebrovascular homeostasis is due to the actions of estrogen alone, but rather the interplay of estrogen and other hormones and their associated receptor expression. The potential interactions of these hormones in the maintenance of normal cerebrovascular tone need to be elucidated. Additional studies are needed to define the role that estrogen and other sex hormones may play in the cerebrovascular circulation and the pathogenesis and rupture of cerebral aneurysms. Efforts directed at understanding the basic pathophysiological mechanisms of aneurysm pathogenesis and rupture promise to yield dividends that may have important therapeutic and clinical implications. The development of non-invasive tools such as molecular MRI for the detection of specific cells, molecular markers, and tissues may facilitate early diagnosis of initial pathophysiological changes that are undetectable by clinical examination or other diagnostic tools, and can also be used to evaluate the state of activity of cerebral aneurysm pathogenesis before, during, and after treatment.  相似文献   

14.
The metallic stent has been widely used in endovascular treatment of intracranial aneurysms and arterial stenosis. Endothelialization at the neck of the aneurysm or stenotic lesion after stent deployment plays a pivotal role in preventing aneurysm recurrence, as well as local thrombus formation and restenosis. To deliver autologous endothelial cells and to promote the endothelialization on the luminal wall of the parent artery, we established an endothelial cell-seeded intracranial stent device. Endothelial cells were isolated from canine jugular vein and identified by FACS assay and immunohistochemistry. We demonstrated that the seeded endothelial cells formed a confluent endothelial layer on the stent's surface. After being brushed with 100 dyne/cm(2) of shear stress, we found that this endothelial layer remained intact for at least 48 h on the heparinized polymer coated stent, rather than the poly-lactic-acid coated stent (p < 0.05). The results suggest that an autologous endothelial cell-seeded stent may be a feasible and optimal tool for endothelial delivery during stenting and may overcome some limitations of the traditional bare stent in the treatment of intracranial aneurysms and arterial stenosis.  相似文献   

15.
目的     探讨64排螺旋CT血管成像(64-SCTA)诊断颅内动脉瘤的临床价值。 方法 回顾性分析82例颅内动脉瘤患者的头颈部64-SCTA检查的多平面重组、容积再现及最大密度投影图像,并与开颅手术及介入栓塞治疗结果对比,评价64-SCTA诊断动脉瘤的准确性。结果 82例患者中, 64-SCTA共发现94个动脉瘤,其中87.8%为单发动脉瘤,9.8%有2个动脉瘤,2.4%有3个动脉瘤。 64-SCTA能清晰显示动脉瘤的瘤体大小、瘤颈、瘤顶指向、载瘤动脉及动脉瘤与邻近血管和骨性组织间的解剖关系。以手术及DSA为标准,64-SCTA漏诊3个动脉瘤,1个动脉瘤为假阳性。64-SCTA检测颅内动脉瘤的敏感性和准确性分别为96.9% 和96%。 结论 64-SCTA是一种快速、无创、准确地检查手段,可作为颅内动脉瘤的首选及常规检查方法,能够提供足够的信息指导动脉瘤的治疗。  相似文献   

16.
Geometric indices defined on intracranial aneurysms have been widely used in rupture risk assessment and surgical planning. However, most indices employed in clinical settings are currently evaluated based on two-dimensional images that inevitably fail to capture the three-dimensional nature of complex aneurysmal shapes. In addition, since measurements are performed manually, they can suffer from poor inter and intra operator repeatability. The purpose of the current work is to introduce objective and robust techniques for the 3D characterization of intracranial aneurysms, while preserving a close connection to the way aneurysms are currently characterized in clinical settings. Techniques for automatically identifying the neck plane, key aneurysm dimensions, shape factors, and orientations relative to the parent vessel are demonstrated in a population of 15 sidewall and 15 terminal aneurysms whose surface has been obtained by two trained operators using both level-set segmentation and thresholding, the latter reflecting typical clinical practice. Automatically-identified neck planes are shown to be in concordance with those manually positioned by an expert neurosurgeon, and automatically-derived geometric indices are shown to be largely insensitive to segmentation method or operator. By capturing the 3D nature of aneurysmal sacs and by minimizing observer variability, our approach allows large retrospective and prospective studies on aneurysm geometric risk factors to be performed using routinely acquired clinical images.  相似文献   

17.
PurposeThe purpose was to evaluate the incidence and risk factors for rebleeding during cerebral angiography in ruptured intracranial aneurysms.ResultsThere were 184 patients (9.7%) who had suffered rebleeding prior to the securing procedure. Among them, 11 patients experienced rebleeding during DSA and other 173 patients at a time other than DSA. Eight (72.7%) of the 11 patients experienced rebleeding during three-dimensional rotational angiography (3DRA). The incidence of rebleeding during DSA was 0.6% in patients with ruptured intracranial aneurysms. Multivariate logistic regression analysis showed that aneurysm location in anterior circulation [odds ratio=14.286; 95% confidence interval (CI), 1.877 to 250.0; p=0.048] and higher aspect ratio (odds ratio=3.040; 95% CI, 1.896 to 10.309; p=0.041) remained independent risk factors for rebleeding during DSA.ConclusionRuptured aneurysms located in anterior circulation with a high aspect ratio might have the risk of rebleeding during DSA, especially during 3DRA.  相似文献   

18.
This study relates to eye fixation systems with combined optical and audio systems. Many devices for eye diagnostics and some devices for eye therapeutics require the patient to fixate on a small target for a certain period of time, during which the eyes do not move and data from substructures of one or both eyes are acquired and analyzed. With young pediatric patients, a monotonously blinking target is not sufficient to retain attention steadily. We developed a method for modulating the intensity of a point fixation target using sounds appropriate to the child's age and preference. The method was realized as a subsystem of a Pediatric Vision Screener which employs retinal birefringence scanning for detection of central fixation. Twenty-one children, age 2–18, were studied. Modulation of the fixation target using sounds ensured the eye fixated on the target, and with appropriate choice of sounds, performed significantly better than a monotonously blinking target accompanied by a plain beep. The method was particularly effective with children of ages up to 10, after which its benefit disappeared. Typical applications of target modulation would be as supplemental subsystems in pediatric ophthalmic diagnostic devices, such as scanning laser ophthalmoscopes, optical coherence tomography units, retinal birefringence scanners, fundus cameras, and perimeters.  相似文献   

19.
目的探讨320排容积cT血管成像(CTA)对颅内动脉瘤诊断价值。方法选取医院2010年2月-2013年12月间具有完整颅脑数字减影血管造影(DSA)资料的63例颅内动脉瘤患者,所有患者均于起病3d内完成320排容积CTA检查。以DSA检查结果作为诊断金标准,分析病变的影像学特点,并评价320排容积CTA对颅内动脉瘤诊断的准确性。结果颅脑动脉瘤阳性63例,CTA漏诊1例,病灶位于大脑后交通动脉。320排容积CTA对颅内动脉瘤的诊断敏感度及阳性预测值分别为98.41%、100%。按部位统计动脉瘤数量结果如下:颈内动脉海绵窦段4例,大脑前动脉26例,大脑中动脉4例,大脑后动脉8例,大脑前交通动脉10例,大脑后交通动脉5例,基底动脉6例。动脉瘤瘤径为2~22mm。在CTA上,动脉瘤的瘤体位置、大小、瘤颈、瘤顶指向、载瘤动脉及动脉瘤与邻近血管分支和骨性结构的空间关系均能较满意的显示,均与DSA结果相符。结论320排容积CTA诊断颅脑动脉瘤具有较高敏感性,能准确检出颅内的微小动脉瘤,对动脉瘤的空间解剖关系显示更具优势。因此,在临床工作中,320排容积CTA可以成为颅脑动脉瘤的首选影像学检查方法。  相似文献   

20.
This study presents the design, development and implementation of a simple low-cost method of phonocardiography signal detection. Human heart and lung signals are detected by using a simple microphone through a personal computer; the signals are recorded and analysed using LabView software. Amplitude and frequency analyses are carried out for various phonocardiography pathological cases. Methods for automatic classification of normal and abnormal heart sounds, murmurs and lung sounds are presented. Various cases of heart and lung sound measurement are recorded and analysed. The measurements can be saved for further analysis. The method in this study can be used by doctors as a detection tool aid and may be useful for teaching purposes at medical and nursing schools.  相似文献   

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