Reproducibility and differentiation of cervical arteriopathies using in vivo high-resolution black-blood MRI at 3 T

Multimodality Imaging in Cranial Giant Cell Arteritis: First Experience with High-Resolution T1-Weighted 3D Black Blood without Contrast Enhancement Magnetic Resonance Imaging

In order to support or refute the clinical suspicion of cranial giant cell arteritis (GCA), a supplemental imaging modality is often required. High-resolution black blood Magnetic Resonance Imaging (BB MRI) techniques with contrast enhancement can visualize artery wall inflammation in GCA. We compared findings on BB MRI without contrast enhancement with findings on 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/low-dose computed tomography (2-[18F]FDG PET/CT) in ten patients suspected of having GCA and in five control subjects who had a 2-[18F]FDG PET/CT performed as a routine control for malignant melanoma. BB MRI was consistent with 2-[18F]FDG PET/CT in 10 out of 10 cases in the group with suspected GCA. In four out of five cases in the control group, the BB MRI was consistent with 2-[18F]FDG PET/CT. In this small population, BB MRI without contrast enhancement shows promising performance in the diagnosis of GCA, and might be an applicable imaging modality in patients.

Optoacoustic biomarkers of lipids, hemorrhage and inflammation in carotid atherosclerosis

Imaging plays a critical role in exploring the pathophysiology and enabling the diagnostics and therapy assessment in carotid artery disease. Ultrasonography, computed tomography, magnetic resonance imaging and nuclear medicine techniques have been used to extract of known characteristics of plaque vulnerability, such as inflammation, intraplaque hemorrhage and high lipid content. Despite the plethora of available techniques, there is still a need for new modalities to better characterize the plaque and provide novel biomarkers that might help to detect the vulnerable plaque early enough and before a stroke occurs. Optoacoustics, by providing a multiscale characterization of the morphology and pathophysiology of the plaque could offer such an option. By visualizing endogenous (e.g., hemoglobin, lipids) and exogenous (e.g., injected dyes) chromophores, optoacoustic technologies have shown great capability in imaging lipids, hemoglobin and inflammation in different applications and settings. Herein, we provide an overview of the main optoacoustic systems and scales of detail that enable imaging of carotid plaques in vitro, in small animals and humans. Finally, we discuss the limitations of this novel set of techniques while investigating their potential to enable a deeper understanding of carotid plaque pathophysiology and possibly improve the diagnostics in future patients with carotid artery disease.

Risk assessment of vascular complications following manual therapy and exercise for the cervical region: diagnostic accuracy of the International Federation of Orthopaedic Manipulative Physical Therapists framework (The Go4Safe project)

QUESTION

What is the diagnostic accuracy of the International Federation of Orthopaedic Manipulative Physical Therapists (IFOMPT) framework to assess the risk of vascular complications in patients seeking physiotherapy care for neck pain and/or headache?

DESIGN

Cross-sectional diagnostic accuracy study.

PARTICIPANTS

One hundred and fifty patients seeking physiotherapy for neck pain and/or headache in primary care.

METHODS

Nineteen physiotherapists performed the index test according to the IFOMPT framework. Patients were classified as having a high, intermediate or low risk of vascular complications, following manual therapy and/or exercise, derived from the estimated risk of the presence of vascular pathology. The reference test was a consensus medical decision reached by a vascular neurologist and an interventional neurologist, with input from a neuroradiologist. The neurologists had access to clinical data and magnetic resonance imaging of the cervical spine, including an angiogram of the cervical arteries.

OUTCOME MEASURES

Diagnostic accuracy measures were calculated for 'no contraindication' (ie, the low-risk category) and 'contraindication' (ie, the high-risk and intermediate-risk categories) for manual therapy and/or exercise. Sensitivity, specificity, predictive values, likelihood ratios and the area under the curve were calculated.

RESULTS

Manual therapy and/or exercise were contraindicated in 54.7% of the patients. The sensitivity of the IFOMPT framework was low (0.50, 95% CI 0.39 to 0.61) and its specificity was moderate (0.63, 95% CI 0.51 to 0.75). The positive and negative likelihood ratios were weak at 1.36 (95% CI 0.93 to 1.99) and 0.79 (95% CI 0.60 to 1.05), respectively. The area under the curve was poor (0.57, 95% CI 0.49 to 0.65).

CONCLUSION

The IFOMPT framework has poor diagnostic accuracy when compared with a reference standard consisting of a consensus medical decision.

Patterns of ischemic posterior circulation strokes: A clinical, anatomical, and radiological review

Background

Posterior circulation and anterior circulation strokes share many clinical, pathogenetic and radiological features, although some clinical signs are highly specific to posterior circulation strokes. Arterial stenosis and occlusions occur in significant numbers in both acute posterior circulation and anterior circulation strokes, making them good candidates for endovascular treatment. Among posterior circulation strokes, basilar artery occlusions stand out because of the diagnostic and acute treatment challenges.

Methods

We reviewed the literature on clinical stroke syndromes and neuroimaging findings and systematically describe for each anatomical site of stroke the detailed clinical and radiological information (anatomical representation, diffusion weighted imaging and angiographic sequences). The principles of neuroimaging of posterior circulation strokes and the prognosis for each stroke localization are also discussed.

Review summary

Stroke syndromes in the territories of the vertebral, basilar, cerebellar, and posterior cerebral arteries are presented. Features typical of posterior circulation strokes are highlighted, including patterns of basilar artery occlusions. Clinical severity and prognosis of posterior circulation strokes are highly variable, and given that they are more difficult to detect on CT-based neuroimaging, magnetic resonance imaging is the technique of choice in suspected posterior circulation strokes. Rapid identification of arterial occlusion patterns may provide prognostic information and support acute revascularization decisions.

Conclusions

Posterior circulation stroke syndromes tightly reflect lesion localization and arterial occlusion patterns. Although many clinical and pathogenetic features are similar to anterior circulation strokes, notable differences exist in terms of clinical presentation, stroke mechanism, prognosis, and response to acute recanalization.

A Review on the Value of Imaging in Differentiating between Large Vessel Vasculitis and Atherosclerosis

Imaging is becoming increasingly important for the diagnosis of large vessel vasculitis (LVV). Atherosclerosis may be difficult to distinguish from LVV on imaging as both are inflammatory conditions of the arterial wall. Differentiating atherosclerosis from LVV is important to enable optimal diagnosis, risk assessment, and tailored treatment at a patient level. This paper reviews the current evidence of ultrasound (US), 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography (FDG-PET), computed tomography (CT), and magnetic resonance imaging (MRI) to distinguish LVV from atherosclerosis. In this review, we identified a total of eight studies comparing LVV patients to atherosclerosis patients using imaging—four US studies, two FDG-PET studies, and two CT studies. The included studies mostly applied different methodologies and outcome parameters to investigate vessel wall inflammation. This review reports the currently available evidence and provides recommendations on further methodological standardization methods and future directions for research.

Imaging strategies for safety surveillance after renal artery denervation

Renal denervation has emerged as a safe and effective therapy to lower blood pressure in hypertensive patients. In addition to the main renal arteries, branch vessels are also denervated in more contemporary studies. Accurate and reliable imaging in renal denervation patients is critical for long-term safety surveillance due to the small risk of renal artery stenosis that may occur after the procedure. This review summarizes three common non-invasive imaging modalities: Doppler ultrasound (DUS), computed tomography angiography (CTA), and magnetic resonance angiography (MRA). DUS is the most widely used owing to cost considerations, ease of use, and the fact that it is less invasive, avoids ionizing radiation exposure, and requires no contrast media use. Renal angiography is used to determine if renal artery stenosis is present when non-invasive imaging suggests renal artery stenosis. We compiled data from prior renal denervation studies as well as the more recent SPYRAL-HTN OFF MED Study and show that DUS demonstrates both high sensitivity and specificity for detecting renal stenosis de novo and in longitudinal assessment of renal artery patency after interventions. In the context of clinical trials DUS has been shown, together with the use of the baseline angiogram, to be effective in identifying stenosis in branch and accessory arteries and merits consideration as the main screening imaging modality to detect clinically significant renal artery stenosis after renal denervation and this is consistent with guidelines from the recent European Consensus Statement on Renal Denervation.

SCMR Position Paper (2020) on clinical indications for cardiovascular magnetic resonance

The Society for Cardiovascular Magnetic Resonance (SCMR) last published its comprehensive expert panel report of clinical indications for CMR in 2004. This new Consensus Panel report brings those indications up to date for 2020 and includes the very substantial increase in scanning techniques, clinical applicability and adoption of CMR worldwide. We have used a nearly identical grading system for indications as in 2004 to ensure comparability with the previous report but have added the presence of randomized controlled trials as evidence for level 1 indications. In addition to the text, tables of the consensus indication levels are included for rapid assimilation and illustrative figures of some key techniques are provided.

Quantitative assessment of carotid artery atherosclerosis by three-dimensional magnetic resonance and two-dimensional ultrasound imaging: a comparison study

Background

It has been proven that magnetic resonance (MR) and ultrasound imaging are useful tools in the quantification of carotid atherosclerotic plaques. However, there are only a few pieces of evidence to illustrate the links of quantitative measurements of carotid plaques between MR and ultrasound imaging. This study looked to compare the quantitative measurements of carotid plaques and investigate their relationship between three-dimensional (3D) MR vessel wall imaging and two-dimensional (2D) ultrasound imaging.

Methods

Seventy-five asymptomatic elderly subjects (mean age: 73.3±5.7 years; 45 males) with carotid atherosclerotic plaques diagnosed by both ultrasound and MR imaging were included in this study. The plaque size, including the maximum wall thickness (Max WT), plaque length, and plaque area, was measured by 3D MR and ultrasound imaging on longitudinal and cross-sectional views. The quantitative assessments of carotid plaque size were compared and correlated between 3D MR and 2D ultrasound imaging.

Results

In total, the quantitative measurements of 101 plaques on longitudinal views or 44 plaques on cross-sectional views of both MR and ultrasound imaging were compared. The Max WT of the plaques (longitudinal: 2.9±0.8 vs. 2.4±0.9 mm; cross-sectional: 3.2±1.1 vs. 2.6±0.7 mm) and plaque areas (longitudinal: 24.3±13.4 vs. 17.0±12.7 mm²; cross-sectional: 24.9±24.6 vs. 16.8±13.3 mm²) measured by MR imaging were found to be significantly higher than those measured by ultrasound imaging (all P<0.001). Moderate to strong correlations were found in Max WT, plaque area, plaque length between 3D MR and ultrasound imaging.

Conclusions

The quantitative measurements of carotid plaques using 3D MR and 2D ultrasound are significantly correlated. The plaque area and Max WT measured by 3D MR imaging are more significant than these parameters measured by 2D ultrasound imaging, which might be explained by the resolution of MR imaging and the workflow of measurements.

High-Resolution Magnetic Resonance Imaging of Cervicocranial Artery Dissection: Imaging Features Associated With Stroke

Background and Purpose- We aimed to systematically investigate the characteristics of cervicocranial artery dissection (CCAD) on high-resolution magnetic resonance imaging that are associated with acute ischemic stroke. Methods- Patients with CCAD were recruited and divided into stroke and nonstroke groups. The lesion location, the presence of a double lumen, intimal flap, intramural hematoma, pseudoaneurysm, irregular surface, intraluminal thrombus, and other quantitative parameters of each dissected segment were reviewed. Multiple logistic regression was used to examine the association between imaging features of CCAD and ischemic stroke. Results- A total of 145 affected vessels from 118 patients with CCAD were analyzed. Anterior circulation, intramural hematoma, irregular surface, intraluminal thrombus, and severe stenosis (>70%) on high-resolution magnetic resonance imaging were more prevalent in CCAD patient with stroke (54.4% versus 36.4%; P=0.030, 96.2% versus 84.8%; P=0.017, 74.7% versus 37.9%; P<0.001, 44.3% versus 4.5%; P<0.001, and 54.4% versus 31.8%; P=0.008, respectively). In multivariable logistic regression analysis, the presence of irregular surface and intraluminal thrombus on imaging were independently associated with acute ischemic stroke in CCAD with odds ratios of 4.29 (95% CI, 1.61-11.46, P=0.004) and 7.48 (95% CI, 1.64-34.07, P=0.009). Conclusions- The current findings supported that the presence of irregular surface and intraluminal thrombus were related to stroke occurrence in patients with CCAD. High-resolution magnetic resonance imaging might give insights into pathogenesis of ischemic stroke in CCAD. It may be useful for individual prediction of ischemic stroke early in CCAD.