Magnetic Resonance Angiography Of Arteries Research Articles

The effect of non-contrast enhanced MRA on patients with renal insufficiency and foot pain.

To investigate the feasibility of non-contrast magnetic resonance angiography of arteries and veins (NATIVE) sampling perfection with application optimized contrasts by using different flip angle evolution (SPACE) and quiescent interval single shot (QISS) in assessing foot arteries of patients with renal insufficiency and foot pain. Fifty-three patients (mean age = 44.2 ± 11.4 years, male: female = 27:26) underwent QISS and NATIVE-SPACE. The source images were reconstructed to maximum intensity projection and volume render. The image quality of QISS and NATIVE-SPACE was rated (0-3, poor to excellent), and was compared using Wilcoxon test. True or false positive was determined by comparing the findings of QISS and NATIVE-SPACE. The relative signal intensity of artery was obtained for each case, and was compared between QISS and NATIVE-SPACE using Mann Whitney test. The acquisition time of NATIVE-SPACE was significantly longer than that of QISS (178.4 ± 35.7 seconds vs 45.4 ± 8.9 seconds, P < .001). QISS had significantly lower image quality score versus NATIVE-SPACE (1.4 ± 0.5 vs 2.4 ± 0.6, P = .02). Fifteen percentage (8/53) NATIVE-SPACE cases had poor image quality due to the similarity of peak flow and minimum flow. The relative signal intensity was significantly lower in QISS versus NATIVE-SPACE (9.7 ± 1.3 vs 68.2 ± 12.4, P < .001). NATIVE-SPACE is valuable in evaluating foot arteries of patients with renal insufficiency. QISS can serve as an alternative test to NATIVE-SPACE.

Retracted: Changes of Short-Term Heart Rate Variability and Vertebral Artery Magnetic Resonance Angiography in Patients with Cervical Vertigo

Retracted: Changes of Short-Term Heart Rate Variability and Vertebral Artery Magnetic Resonance Angiography in Patients with Cervical Vertigo

Characteristics and predictors of low-grade renal artery stenosis in female patients with CKD

ABSTRACT Aim Renal artery stenosis (RAS) is an important cause of chronic kidney disease (CKD). The main purpose of this study was to explore the clinical characteristics and predictors of low-grade RAS in female patients with CKD. Methods One hundred and five female CKD patients from Huadong Hospital affiliated with Fudan University who underwent 3 T non-contrast renal artery magnetic resonance angiography (MRA) were analyzed. Basic statistics methods were used in the study, such as independent-sample t test,non-parametric test, binary logistic regression analysis and ROC analysis. Results In this cross-sectional study, there were 50 patients with RAS and 55 without RAS (47.6% versus 52.4%). Binary logistic regression analysis demonstrated that low-level ALB and lymphocyte count, high-level SP, BUN and NLR were independent risk factors for low-grade RAS in female patients with CKD. ROC analysis indicated that eGFR, FeNa and UBCR, ALB, lymphocyte count and NLR had the best predictive value for low-grade RAS, especially eGFR with a sensitivity of 65.50% and specificity of 72.00% and FeNa with a sensitivity of 71.10% and specificity of 72.20% and BUCR with a sensitivity of 71.10% and specificity of 68.10%. Conclusion In female patients with CKD, FeNa, eGFR, ALB, UBCR, lymphocyte count and NLR may be good predictors of low-grade RAS, especially eGFR, FeNa and BUCR.

A clinical observation of recurrent painful ophthalmoplegic neuropathy in a 49-year old female patient

Recurrent painful ophthalmoplegic neuropathy is a rare clinical syndrome, included into the International Classification of Headache Disorders, 3rd edition, and characterized by recurrent headache episodes associated with dysfunction of one or more ocular motor nerves. The diagnosis implies mandatory exclusion of other potential causes of the symptoms. The paper presents a clinical case of a 49-year old female patient with a unilateral headache paroxysms and subsequent paresis of the oculomotor nerve. A thorough clinical assessment, with neuroimaging (brain magnetic resonance imaging and magnetic resonance angiography of arteries and veins of the head) showed no morphological abnormalities that could cause clinical symptoms of oculomotor neuropathy. Her past history was remarkable for a similar episode of prolonged unilateral headache and oculomotor paresis about 10 years before, which were at that time considered as an acute cerebrovascular accident. Thus, two episodes of similar clinical signs of painful neuropathy, the absence of other possible causes of the disease, and the complete regression of symptoms after treatment (ibuprofen and gabapentin) confirmed the diagnosis of recurrent painful ophthalmoplegic neuropathy.

The Utility of Unenhanced Renal Artery Magnetic Resonance Angiography Using Inhance Sequence in Depiction of Renal Vasculature and Related Abnormalities in Patients with Suspected Renovascular Hypertension

The Utility of Unenhanced Renal Artery Magnetic Resonance Angiography Using Inhance Sequence in Depiction of Renal Vasculature and Related Abnormalities in Patients with Suspected Renovascular Hypertension

Added diagnostic yield of temporal artery magnetic resonance angiography in the evaluation of giant cell arteritis.

Temporal artery magnetic resonance angiography (TAMRA) is a useful tool to investigate possible diagnoses of GCA. As acquired images also reveal other local structures, they may assist in finding alternative diagnoses when assessing for possible GCA. We sought to assess the utility of TAMRA in identifying other significant abnormalities either associated with a diagnosis of GCA or potentially mimicking a clinical presentation of GCA. A retrospective cohort study was undertaken at St Joseph's Healthcare in Hamilton, Ontario, Canada between February 2007 and April 2020 and included patients who underwent TAMRA for a possible diagnosis of GCA. Patient demographics, diagnosis and imaging findings were extracted, and descriptive analysis of findings was performed. We included 340 individuals who underwent TAMRA for assessment of a potential diagnosis of GCA and had clinical information available; there were 126 (37.1%) diagnoses of GCA. Fourteen (4.1%) patients had findings on TAMRA that demonstrated an alternative diagnosis, findings were predominantly in the temporomandibular joint, orbit and meninges. Eighteen (14.3%) patients with GCA had intracranial vascular changes that were demonstrative of intracranial vasculitis; one stroke was attributed to intracranial GCA. TAMRA has proven utility in diagnosing GCA, and these data suggest that it also has utility in identifying alternative diagnoses to rule out the disease. Intracranial vasculitis was also seen in 14.3% of patients; the clinical impact of these findings is currently poorly understood and requires further study.

Changes of Short-Term Heart Rate Variability and Vertebral Artery Magnetic Resonance Angiography in Patients with Cervical Vertigo.

Cervical vertigo refers to a clinical syndrome with sudden vertigo as the main symptom caused by the hemodynamic disturbance of the extracranial segment of the vertebral artery (VA) affected by cervical vertebral lesions. Small differences in pulse intervals in a patient's continuous sinus rhythm are called heart rate variability (HRV). Heart rate variability refers to the small rise and fall of instantaneous heart rate between consecutive beats and is one of the most important physiological indicators of cardiac function. Small changes between successive beats reflect some information about the heart. So, it can be used to diagnose heart disease; its parameters can be used to identify emotions. Therefore, it is possible to use the characteristics of heart rate variability to find some patterns in the high-stress state and use the computer and ECG signals to describe the high-stress state. Since the ECG signal is a universal and objective model, it is practical and convenient to use it to describe stress states. Magnetic resonance angiography (MR angiography, MRA) is a noninvasive vascular imaging method that does not require intubation and contrast agents. At present, it has been widely used in clinical practice. In order to explore the changes of short-term heart rate variability and vertebral arterial magnetic resonance angiography (MRA) in patients with cervical vertigo and their clinical significance, this paper introduces two basic analysis methods of heart rate variability and commonly used MRA techniques, TOF technology. In the analysis of heart rate variability in patients with cervical vertigo, the statistical values of time and spectrum domain parameters were found to be lower in the experimental group than in the control group1. MRA showed that the abnormal rate of VA in the PCI group and the cervical vertigo group was similar. In the RMSSD index, the male experimental group reached 29, and the control group 1 reached 22.

Coronary Artery Magnetic Resonance Angiography Combined with Computed Tomography Angiography in Diagnosis of Coronary Heart Disease by Reconstruction Algorithm.

This research aimed at discussing the diagnosis effect of coronary artery magnetic resonance angiography (MRA) combined with computed tomography (CT) angiography (CTA) based on the back-projection filter reconstruction (BPFR) algorithm in coronary heart disease (CHD), and its role in the diagnosis of coronary artery disease (CAD). Sixty patients with CHD were selected and randomly rolled into group A (undergone MRA examination), group B (undergone CTA examination), and group C (undergone MRA + CTA), with 20 cases in each group. Taking the diagnostic results of coronary angiography as the gold standard, the MRA and CTA images were reconstructed using a BPFR algorithm, and a filter function was added to solve the problem of image sharpness. In addition, the iterative reconstruction algorithm and the Fourier transform analysis method were introduced. As a result, the image clarity and resolution obtained by the BPFR algorithm were better than those obtained by the Fourier transform analytical method and the iterative reconstruction algorithm. The accuracy of group C for the diagnosis of mild coronary stenosis, moderate stenosis, and severe stenosis was 94.02%, 96.13%, and 98.01%, respectively, which was significantly higher than that of group B (87.5%, 90.2%, and 88.4%) and group C (83.4%, 89.1%, and 91.5%) (P < 0.05). The sensitivity and specificity for the diagnosis of noncalcified plaque in group C were 87.9% and 89.2%, respectively, and the sensitivity and specificity for the diagnosis of calcified plaque were 84.5% and 78.4%, respectively, which were significantly higher than those in groups B and C (P < 0.05). In summary, the BPFR algorithm had good denoising and artifact removal effects on coronary MRA and CTA images. The combined detection of reconstructed MRA and CTA images had a high diagnostic value for CHD.

Wernicke encephalopathy with epileptic seizures during pregnancy

ABSTRACT A 22-year-old woman was admitted to the emergency department with headache, dizziness, and numbness on the left side of the body. Neurologic examination revealed gaze-evoked nystagmus. Cranial magnetic resonance imaging, venous and arterial magnetic resonance angiography were normal. Generalized epileptogenic activity was observed in the electroencephalography. The erythrocyte thiamine transketolase levels were found to be 13 u/L. She received intravenous thiamine. On discharge, she had no neurologic sequelae. The diagnosis of Wernicke encephalopathy in our patient is based on increased thiamine requirement due to pregnancy, nystagmus, low transketolase level, and reversal of symptoms after thiamine replacement. .

Paroxysmal hemicrania associated to carotid artery dissection: a case report

There are numerous case reports relating trigeminal autonomic cephalalgias to structural injuries. However there is no description of the association between paroxysmal hemicrania and carotid artery dissection. We describe a previously healthy 63-year-old male presented with the onset of severe, throbbing pain in the right frontal region, lasting between 10 and 30 minutes, with a frequency of approximately two to three attacks per day, which began two days before seeking medical care. Pain was associated with ipsilateral tearing, semiptosis and nasal congestion. A cervical arterial magnetic resonance angiography demonstrated left carotid artery dissection in the C1/C2 segment of the left internal carotid artery. The patient became asymptomatic after indomethacin use. We conclude that the possibility of investigating carotid dissection should be considered in patients with paroxysmal hemicrania.

High-resolution, non-contrast-enhanced magnetic resonance angiography of the wrist, hand and digital arteries using optimized implementation of Cartesian quiescent interval slice selective (QISS) at 1.5 T

PurposeNon-contrast-enhanced (CE) magnetic resonance angiography (MRA) techniques are of considerable interest for diagnosing vascular diseases in the upper extremities owing to the possibility of repeated examinations, sufficient coverage of the measurement volume, and because possible side effects of administering iodine- or gadolinium-based contrast agents and radiation exposure can be avoided. The aim of this study was to investigate the feasibility of an optimized electrocardiogram (ECG) triggered Cartesian quiescent interval slice selective (QISS) technique for MRA of hand arteries. Material and methodsBoth hands of 20 healthy volunteers (HVs) were examined using an optimized QISS-MRA pulse sequence at 1.5 Tesla. The wrist and hand arterial trees were divided into 36 segments. Cross-sectional areas (CSA) of all arterial segments were measured. For the technical evaluation of the pulse sequence, the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were computed and six imaging artifacts were graded. Two experienced observers used an ordinal scoring system to assess the image quality of each arterial segment. Interobserver agreement was determined. ResultsThe median CSA was 7.3 mm2 in the ulnar and radial artery, 3.2 mm2 in the four common digital arteries, and 1.5 mm2 in five proper digital arteries. The median SNR and CNR of the third common proper arteries were 45.9 and 20.3, respectively. None of the arterial segments were contaminated by venous enhancement. The image quality of arterial segments for both hands was considered as diagnostic in 87.2% of all 1440 segments. An interobserver agreement of 0.67 for both hands was determined for image quality of arterial segments using a five-grade scoring system. Optimized QISS-MRA allows as the first MRA technique the classification of superficial palmar arch (SPA) and deep palmar arch (DPA) variants. 5 new SPA and 6 new DPA variants could be classified using QISS-MRA in comparison with previous studies using CE computed tomography angiography and using fixed cadaver hands. ConclusionsBy using this optimized 2D Cartesian QISS-MRA protocol, contrast agent-free angiography of the wrist and hand arteries provided a high in-plane spatial resolution and an excellent visualization of small digital arteries.

Contextualizing temporal arterial magnetic resonance angiography in the diagnosis of giant cell arteritis: a retrospective cohort study.

Imaging modalities have become common in evaluating patients for a possible diagnosis of GCA. This study seeks to contextualize how temporal arterial magnetic resonance angiography (TA-MRA) can be used in facilitating the diagnosis of GCA. A retrospective cohort study was performed on patients who had been previously referred to a rheumatologist for evaluation of possible GCA in Hamilton, Ontario, Canada. Data including clinical features, inflammatory markers, imaging, and biopsy results were extracted. Multivariable logistic regression model to predict the diagnosis of GCA. Using these models, the utility of TA-MRA in series with or in parallel to clinical evaluation was demonstrated across the cohort as well as in subgroups defined by biopsy and imaging status. In total 268 patients had complete data. Those diagnosed with biopsy- and/or imaging-positive GCA were more likely to demonstrate classic features including jaw claudication and vision loss. Clinical multivariable modelling allowed for fair discriminability [receiver operating characteristic (ROC) 0.759, 95% CI: 0.703, 0.815] for diagnosing GCA; there was excellent discriminability in facilitating the diagnosis of biopsy-positive GCA (ROC 0.949, 0.898-1.000). When used in those with a pre-test probability of 50% or higher, TA-MRA had a positive predictive value of 93.0%; in those with a pre-test probability of 25% or less TA-MRA had a negative predictive value of 89.5%. In those with high disease probability, TA-MRA can effectively rule in disease (and replace temporal artery biopsy). In those with low to medium probability, TA-MRA can help rule out the disease, but this continues to be a challenging diagnostic population.

Multimodal evaluation of the cerebrovascular reserve in Neurofibromatosis type 1 patients with Moyamoya syndrome

PurposeMoyamoya syndrome (MMS) is a rare intracranial arterial vasculopathy which can occur in neurofibromatosis type 1 (NF1) disease, representing a cause of cerebrovascular reserve (CVR) impairment, possibly leading to ischemic stroke. Here, we evaluated noninvasive imaging techniques used to assess CVR in MMS patients, describing clinical and imaging findings in patients affected by MMS-NF1.MethodsFollowing strict inclusion and exclusion criteria, in this retrospective observational study, we evaluated imaging data of nine consecutive MMS-NF1 patients (M/F = 5/4, mean age: 12.6 ± 4.0). Subjects underwent a multimodal evaluation of cerebral vascular status, including intracranial arterial MR Angiography (MRA), MRI perfusion with dynamic susceptibility contrast (DSC) technique, and 99mTc-hexamethylpropyleneamine oxime (HMPAO) SPECT.ResultsIn 8 out 9 patients (88.8%, 6/8 symptomatic), time-to-peak maps were correlated with the involved cerebral hemisphere, while in 6 out 9 patients (66.6%, 5/6 symptomatic), mean transit time (MTT) maps showed correspondence with the affected cerebrovascular territories. Cerebral blood flow (CBF) calculated using DSC perfusion failed to detect the hypoperfused regions instead identified by SPECT-CBF in all patients, while MTT maps overlapped with SPECT-CBF data in all cases and time-to-peak maps in 60.0%.ConclusionsAlthough SPECT imaging still represents the gold standard for CBF assessment, our results suggest that data obtained using DSC perfusion technique, and in particular MTT maps, might be a very useful and noninvasive tool for evaluating hemodynamic status in MMS-NF1 patients.

Study on the risk prediction for cerebral infarction after transient ischemic attack: A STROBE compliant study.

Transient ischemic attack (TIA) is often recurrent, and about one-third of patients will progress to cerebral infarction. Rapidly identifying high-risk patients is pivotal to prevent the development of cerebral infarction. Therefore, this study aimed to evaluate the value of ABCD2 score, ABCD2 score combined with magnetic resonance diffusion weighted imaging (DWI) and intracranial arterial magnetic resonance angiography (MRA) in predicting cerebral infarction after 2 to 30 days of transient ischemic attack (TIA).182 patients with TIA from August 2011 to August 2014 were enrolled as study subjects, and their clinical data, test results of DWI and MRA were collected. The incidence of cerebral infarction was observed at 2 days, 7 days and 30 days after TIA in patients with TIA, through scoring according to the 7-point ABCD2 score method proposed by Johnston. The relationship between ABCD2 score, performances of DWI and MRA and the early incidence of cerebral infarction after TIA was analyzed. The accuracy rating of ABCD2 score and ABCD2 + DWI + MRA score used for predicting the early incidence of cerebral infarction after TIA were compared with each other.The incidence of cerebral infarction after TIA was 19 cases (10.4%) in 2 days, 42 cases (23.1%) in 7 days, 56 cases (30.8%) in 30 days respectively. For the ABCD2 score of incidence of cerebral infarction 2 to 30 days after TIA, that of those with high risk was higher than that with medium risk, and that with the medium risk was higher than that with low risk (P < .05). The area under the curve of ABCD2 + DWI + MRA score and ABCD2 score predicting the incidence of cerebral infarction was: in 2 days: 0.782 and 0.748, in 7 days: 0.839 and 0.801, in 30 days: 0.780 and 0.757, P < .05.Compared with ABCD2 score, ABCD2 score combined with DWI and MRA can further improve the accuracy of prediction for cerebral infarction after TIA.

Feasibility of contrast-enhanced coronary artery magnetic resonance angiography using compressed sensing

BackgroundCoronary magnetic resonance angiography (CMRA) is a promising technique for assessing the coronary arteries. However, a disadvantage of CMRA is the comparatively long acquisition time. Compressed sensing (CS) can considerably reduce the scan time. The aim of this study was to verify the feasibility of CS CMRA scanning during the waiting time between contrast injection and late gadolinium enhancement (LGE) scan in a clinical protocol.MethodsFifty clinical patients underwent contrast-enhanced CS CMRA and conventional CMRA on a 3 T CMR scanner. After contrast injection, CS CMRA was scanned during the waiting time for LGE CMR. A conventional CMRA scan was performed after LGE CMR. We assessed acquisition times and coronary artery image quality for each segment on a 4-point scale. Visible vessel length, sharpness and diameter of right (RCA), left anterior descending (LAD), and left circumflex (LCX) coronary arteries were also quantitatively compared among the scans.ResultsAll CS CMRA scans were successfully performed within the LGE waiting time. The median total scan time was 207 s (163, 259 s) for CS and 785 s (698, 975 s) for conventional CMRA (p < 0.001). No significant differences were observed in image quality scores, vessel length measurements, sharpness, and diameter between CS and conventional CMRA.ConclusionsWe could achieve all CS CMRA scans within the LGE waiting time. Contrast-enhanced CS CMRA could considerably shorten the scan time while maintaining image quality compared with conventional CMRA.

Multi-contrast imaging information of coronary artery wall based on magnetic resonance angiography

In order to explore the most suitable image acquisition method for coronary artery wall, the display ability and image quality of segmentation breath-holding target volume acquisition method (the breath-holding method) and real-time navigation whole-hearted acquisition method (the navigation method) of coronary artery magnetic resonance angiography (CMRA) were compared. 26 healthy volunteers were selected to accept the CMRA in 1.5 tunnels magneto-resistance (TMR) equipment by the 2 acquisition methods respectively. The arteries were divided into 9 segments according to the standards of the American Heart Association (AHA). The images were evaluated by 2 magnetic resonance physicians. Satisfaction rate and success rate of each segment of the coronary artery were counted. The results showed that the signal to noise ratio (SNR) and the carrier to noise ratio (CNR) of the images obtained by the breath-holding method were higher than those obtained by the navigation method (P<0.05). Therefore, the segmentation breath-holding target volume acquisition method is proved to have a higher image quality and the simpler and more convenient operations, which is more suitable for the acquisition of positioning images of CMRA.

Multi-phase coronary magnetic resonance angiography improves delineation of coronary arteries.

AbstractBackgroundCoronary artery magnetic resonance angiography (CMRA) is a robust tool for delineation of the coronary artery anatomy. In order to overcome the issue of visual delineation of the ...

Fast carotid artery MR angiography with compressed sensing based three-dimensional time-of-flight sequence

ObjectiveIn this study, we sought to investigate the feasibility of fast carotid artery MR angiography (MRA) by combining three-dimensional time-of-flight (3D TOF) with compressed sensing method (CS-3D TOF). Materials and methodsA pseudo-sequential phase encoding order was developed for CS-3D TOF to generate hyper-intense vessel and suppress background tissues in under-sampled 3D k-space. Seven healthy volunteers and one patient with carotid artery stenosis were recruited for this study. Five sequential CS-3D TOF scans were implemented at 1, 2, 3, 4 and 5-fold acceleration factors for carotid artery MRA. Blood signal-to-tissue ratio (BTR) values for fully-sampled and under-sampled acquisitions were calculated and compared in seven subjects. Blood area (BA) was measured and compared between fully sampled acquisition and each under-sampled one. ResultsThere were no significant differences between the fully-sampled dataset and each under-sampled in BTR comparisons (P>0.05 for all comparisons). The carotid vessel BAs measured from the images of CS-3D TOF sequences with 2, 3, 4 and 5-fold acceleration scans were all highly correlated with that of the fully-sampled acquisition. The contrast between blood vessels and background tissues of the images at 2 to 5-fold acceleration is comparable to that of fully sampled images. The images at 2× to 5× exhibit the comparable lumen definition to the corresponding images at 1×. ConclusionBy combining the pseudo-sequential phase encoding order, CS reconstruction, and 3D TOF sequence, this technique provides excellent visualizations for carotid vessel and calcifications in a short scan time. It has the potential to be integrated into current multiple blood contrast imaging protocol.

Geometric modeling of hepatic arteries in 3D ultrasound with unsupervised MRA fusion during liver interventions.

Modulating the chemotherapy injection rate with regard to blood flow velocities in the tumor-feeding arteries during intra-arterial therapies may help improve liver tumor targeting while decreasing systemic exposure. These velocities can be obtained noninvasively using Doppler ultrasound (US). However, small vessels situated in the liver are difficult to identify and follow in US. We propose a multimodal fusion approach that non-rigidly registers a 3D geometric mesh model of the hepatic arteries obtained from preoperative MR angiography (MRA) acquisitions with intra-operative 3D US imaging. The proposed fusion tool integrates 3 imaging modalities: an arterial MRA, a portal phase MRA and an intra-operative 3D US. Preoperatively, the arterial phase MRA is used to generate a 3D model of the hepatic arteries, which is then non-rigidly co-registered with the portal phase MRA. Once the intra-operative 3D US is acquired, we register it with the portal MRA using a vessel-based rigid initialization followed by a non-rigid registration using an image-based metric based on linear correlation of linear combination. Using the combined non-rigid transformation matrices, the 3D mesh model is fused with the 3D US. 3D US and multi-phase MRA images acquired from 10 porcine models were used to test the performance of the proposed fusion tool. Unimodal registration of the MRA phases yielded a target registration error (TRE) of [Formula: see text]mm. Initial rigid alignment of the portal MRA and 3D US yielded a mean TRE of [Formula: see text]mm, which was significantly reduced to [Formula: see text]mm ([Formula: see text]) after affine image-based registration. The following deformable registration step allowed for further decrease of the mean TRE to [Formula: see text]mm. The proposed tool could facilitate visualization and localization of these vessels when using 3D US intra-operatively for either intravascular or percutaneous interventions to avoid vessel perforation.

Diagnostic accuracy of Dixon water fat suppression coronary artery magnetic resonance angiography at 3.0 Tesla

Diagnostic accuracy of Dixon water fat suppression coronary artery magnetic resonance angiography at 3.0 Tesla