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In recent years, cerebral artery stenting has become an effective method for the treatment of cerebral artery stenosis. However, methods for assessing efficacy and techniques for follow-up imaging still need to be developed. This study was designed to evaluate the application of transcranial color-coded sonography (TCCS) in assessing stenting of mi...
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... TCCS has some advantages in diagnosing intra-axial intracranial hematomas (intraparenchymal hematomas), extra-axial intracranial hematomas (epidural and subdural hematomas), brain midline shift, hydrocephaly, brain tumors, cerebral aneurysms, and arteriovenous malformations [21]. Although real-time dynamic morphological information is achieved via color or power Doppler ow imaging of TCCS [23], it has been reported that only 55-80% of basal cerebral arteries can be determined via unenhanced TCCS [24]. ...
Background: Stroke is the most common neurological disorder with a high incidence in Middle-eastern
... TCCS has some advantages in diagnosing intra-axial intracranial hematomas (intraparenchymal hematomas), extra-axial intracranial hematomas (epidural and subdural hematomas), brain midline shift, hydrocephaly, brain tumors, cerebral aneurysms, and arteriovenous malformations [21]. Although real-time dynamic morphological information is achieved via color or power Doppler ow imaging of TCCS [23], it has been reported that only 55-80% of basal cerebral arteries can be determined via unenhanced TCCS [24]. ...
Background: Stroke is the most common neurological disorder with a high incidence in Middle-eastern regions. We aimed to assess the diagnostic accuracy of transcranial color-coded duplex sonography (TCCS) for detection of cerebral artery stenosis compared to digital subtraction angiography (DSA) as a gold standard method.
Methods: Eighty patients presenting with symptoms of cerebral ischemia were enrolled in the study. They were examined by color-coded Doppler and TCCS to determine stenosis of extracranial and intracranial arteries, respectively. DSA was performed 24-48 hours after the initial examination. The sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and accuracy of TCCS in comparison to DSA was calculated. The agreement between the two methods was determined by kappa statistics.
Results: Eighty patients (60% male, 40% female) with a mean age of 61.32±12.6 years were included. In 65% of cases, pathology in carotid artery was responsible for ischemia. We did not observe any abnormalities in the anterior cerebral artery (ACA), posterior cerebral artery (PCA) as well as basilar artery (BA). The agreement between TCCS and DSA in various arterial vessels were 0.9 for common carotid artery (CCA), 0.86 for internal carotid artery (ICA), 0.78 for middle cerebral artery (MCA), and 0.86 for vertebral artery (VA). The sensitivity, specificity, PPV, NPV, accuracy, and kappa value of TCCS for detection of stenosis regarding the arterial segments were 84.8%, 81%, 92.6%, 65.4%, 83.8, and 0.71, respectively.
Conclusion: TCCS is a valuable, non-invasive, and repeatable method to investigate cerebral artery stenosis with high diagnostic accuracy.
... Digital subtraction angiography (DSA) is the gold standard for diagnosing intracranial arterial stenosis; however, it is expensive, invasive and unable to detect haemodynamic changes. Therefore, DSA cannot be executed within a short time frame and cannot be used for follow-up testing following stent placement (10). Due to developments in medical imaging technology, various methods exist to study the haemodynamics of these patients, comprising computed tomographic perfusion (11), positron emission tomography (PET) and single photon emission computed tomography (SPECT) (12). ...
... However, as with other endovascular procedures, an effective and convenient method of assessing treatment efficacy and follow-up has not yet been developed. Furthermore, there is insufficient research available to detect the haemodynamic changes that occur following stent placement (10). ...
The most effective strategy to assess changes in the brain haemodynamics of stent angioplasty in patients with symptomatic ischemia of the M1 segment of the middle cerebral artery (MCA) remains unknown. The purpose of the present study was to use perfusion-weighted magnetic resonance imaging (PWI) to evaluate the effect of stent angioplasty in treating patients with symptomatic MCA plaque stenosis. Stent angioplasty was performed on 23 patients with reduplicative transient ischaemic attack who were refractory to medical therapy. All patients had MCA plaque stenosis at the M1 segment. Brain PWI was obtained from four major regions of interest (ROIs) at the frontal parietal, temporal, lateral ventricle and basal ganglia lobes prior to and following stent implantation. In addition, cerebral blood flow (CBF), cerebral blood volume, mean transit time (MTT) and time to peak (TTP) parameters derived from PWI were calculated. All patients underwent digital subtraction angiography following surgery to confirm the patency. Computed tomography angiography or PWI was performed 1 week and 3 months post-surgery. According to pre-operative PWI, there was significant hypoperfusion in the symptomatic frontal parietal, temporal, lateral ventricle and basal ganglia lobes. By contrast, the regional CBF and CBF increased in the ROIs of the affected cerebral hemisphere 3 months after stent implantation (P<0.05 vs. pre-operative data). Additionally, post-operative MTT and TTP in the ROIs on the operative side were significantly shorter than pre-operative MTT and TTP (P<0.05). During the follow-up period, the frequency of transient ischaemic attack was reduced or disappeared in all patients during the follow-up. In conclusion, PWI enables an effective and objective assessment of haemodynamics prior to and following stent angioplasty in patients with plaque stenosis of MCA at the M1 segment.
... As a result, repeated DSA tests within a short time span are not preferred, and therefore, TCCS was used in our study. In a report of Wang et al., where 43 patients were examined with middle cerebral artery stent by TCCS and confirmed through DSA, a high sensitivity, specificity, and accuracy in diagnosing intracranial artery stenosis was found [13]. Unlike the first generation of nitinol self-expanding microstents (Wingspan and Neuroform, both Stryker) sharing the same open-cell stent design and a duplicated radial force for Wingspan, Acclino is a closed-cell design stent with a reduced radial force comparable with Enterprise stent (Codman & Shurtleff, Raynham, MA, USA). ...
Introduction
We present a novel endovascular technique to treat intracranial atherosclerotic stenosis (ICS) with the specific potential to reduce the procedure-related complications which so far limited safety and efficacy of endovascular ICS intervention.
Methods
Six consecutive patients were included in this study with the following criteria of inclusion: (1) failure of dual antiplatelet therapy defined as recurrent TIA or ischemic stroke, (2) presence of ICS of ≥70 %, and (3) endovascular accessibility of the target lesion as judged by CTA or MRA. Technical feasibility, safety, and efficacy were observed for the first-ballon-then-stent (FBTS) technique using the percutaneous transluminal angioplasty (PTA) balloon microcatheter over which a self-expandable microstent can be directly delivered obviating the need to exchange microcatheters.
Results
FBTS was performed in six patients (four female, median age 69, median stenosis 82.5 %) all refractory to best medical treatment: three V4, two M1, and one supraclinoid ICA stenosis. PTA and stent deployment were technically feasible in all patients and immediately effective with a median postprocedural stenosis grade of 10 %. Angiographic and clinical safety measures were met with no occult or clinically evident hemorrhage or ischemic complications (four patients discharged without alteration in mRS, two patients with significant clinical improvement). No occurrence of TIA, stroke, or death was observed during follow-up.
Conclusion
The FBTS method in this series appeared to be safe and effective for the endovascular treatment of ICS. It bears the specific potential to reduce wire perforations, which so far have been linked to major procedure-related adverse events of endovascular ICS treatment.
Background: The feasibility of transcranial color flow imaging (TC-CFI) for evaluation of in-stent flow after flow diverter stenting has not been clarified.
Case: A 59-year-old man was admitted due to headache and was diagnosed as having a dissecting aneurysm of the right vertebral artery (RVA) by magnetic resonance angiography (MRA) and cerebral angiography. Although he was discharged after conservative therapy, he was readmitted due to worsening of his headache 2 months later. Since brain MRA showed enlargement of the dissecting aneurysm, he was treated with flow diverter stenting on day 14 after admission. A 4.5 × 18 mm Pipeline Flex embolization device with Shield technology was placed in the RVA across the dissecting aneurysm. Mild stenosis at the distal part of the Pipeline remained even after percutaneous transluminal angiography. MRA on postoperative day 1 showed decreased signals in the RVA inside the Pipeline. For evaluation of in-stent stenosis, TC-CFI by the foramen magnum approach was performed. The Pipeline was slightly visible on two-dimensional images. TC-CFI at the RVA inside the Pipeline was performed uneventfully and demonstrated normal flow findings, suggesting the absence of in-stent stenosis.
Conclusions: TC-CFI can be used to evaluate in-stent flow after flow diverter stenting.
Neurosonology is non-invasive, portable, and has excellent temporal resolution, making it a valuable and increasingly popular tool for the diagnosis and monitoring of neurological conditions when compared to other imaging techniques. This guide looks beyond the use of neurovascular ultrasound in stroke to encompass a wide range of other neurological diseases and emergencies. It offers a practical approach to the examination of patients, interpretation of ultrasound studies, and the application of neurosonology to the development of management and treatment strategies. Each chapter incorporates a thorough and clear procedural methodology alongside scanning tips for trainees; this step-by-step approach is further enhanced by example images and focused diagnostic questions. Authored and edited by international experts, this practical manual of neurosonology is an invaluable resource for neurologists, neurosurgeons, intensivists, radiologists and ultrasonographers.
Background and Purpose: Cerebral artery stenting is an effective treatment of cerebral artery stenosis. However, methods for assessing efficacy and techniques for follow-up imaging still need to be developed. We report the case of a patient with intracranial stenting in the right middle cerebral artery (MCA), and we evaluated the application of transcranial color flow imaging (TC-CFI).
Case: A 43-year-old man was admitted to our hospital for left hemiparesis that corresponded to a National Institutes of Health Stroke Scale score of 6. Diffusion magnetic resonance imaging revealed an acute symptomatic brain infarct in the right hemicerebrum. Magnetic resonance angiography (MRA) revealed an occlusion at the right horizontal segment (M1), which caused the infarction. Thrombectomy was performed for the M1 occlusion. Recanalization was achieved, although stenosis of the M1 segment accompanying cerebral artery dissection remained. Balloon percutaneous transluminal angioplasty was performed in the stenosed segment, and a 3.0mm × 21mm NeuroForm Atlas stent was then deployed there. The angiogram indicated complete coverage of the stenotic segment by the stent. The stent appeared as hyperechoic images on two-dimensional images. TC-CFI demonstrated blood flow through the hyperechoic stent.
Conclusions: TC-CFI can be considered a quick and effective clinical detection method to evaluate intracranial arterial stenting.
The role of vascular imaging in the assessment of acute stroke has been debated for decades since the demonstration of intravenous tissue-type plasminogen activator (tPA) efficacy.1–3 It would seem logical that a disease involving the vasculature of the brain should require evaluation of that vasculature to best plan appropriate treatment. The major limitation to routine vessel imaging had been access to a modality that can provide this information noninvasively, accurately, and efficiently. Currently, there are 4 imaging modalities capable of providing vascular information in acute stroke. Given the high resource intensity and invasive nature of cerebral angiography, there is little place for this modality as a pure diagnostic tool in the acute stroke setting. The 3 noninvasive tests that could be used in acute stroke include computed tomographic (CT) angiography (CTA), magnetic resonance (MR) angiography (MRA), and transcranial Doppler (TCD)/transcranial color-coded sonography (TCCS)+carotid duplex sonography. This review will consider characteristics (Table 1) important for evaluating and comparing the 3 modalities as the diagnostic tool of choice for acute stroke assessment and treatment decision making. In the past, vascular imaging information did not significantly alter the evidence-based acute treatment plan, but this has now changed with new evidence for endovascular treatment renewing the debate on which should the standard imaging approach be if a patient presents acutely (<6 hours from onset) with acute disabling stroke symptoms?
View this table:
Table 1.
Comparison of Vascular Imaging Techniques
Each of the 3 modalities have different methods of acquisition but are all capable of imaging both the extracranial and intracranial arterial circulation. CTA is a CT technique that requires an injection of intravenous x-ray contrast in the arm with rapid movement of the CT gantry where x-ray information is gathered by a spiral or helical acquisition in 3-dimensional (3D) that starts usually at the aortic arch …
Objective To investigate color Doppler flow imaging (CDFI) and transcranial color-coded sonography (TCCS) for detection and evaluation of severe stenosis of intracranial vertebral artery (IVA) before and after stenting, as well as the hemodynamic changes of restenosis and their clinical value. Methods A total of 102 patients with severe stenosis of IVA confirmed by CDFI plus TCCS and DSA from November 2011 to November 2013 were analyzed retrospectively. Extra- and intracranial segments peak systolic velocity (PSV), end-diastolic velocity (EDV), IVA pulsatility index (PI), extracranial resistance index (RI), tube diameter, spectrum morphology, and hemodynamic parameters before stenting and 1 week, 3, 6 and 12 months after stenting were compared. According to the results of TCCS, they were further divided into either a restnosis group (n = 16) or a non-restnosis group (n = 86). Results (1) The results of TCCS detection showed: PSV, EDV, and PI of the stenotic segments were improved significantly at 1 week after stenting, they were 109 ±40 cm/s vs. 258 ±63 cm/s, 47 ± 18 cm/s vs. 132 ±45cm/s, 0.91 ±0.15 vs. 0.75 ±0.18, respectively. There were significant differences (all P <0.01). PSV and EDV of the restenosis group were increased gradually from 3 to 12 months after procedure. There were significant differences between 12 months after procedure and one week after procedure (all P < 0.01). There were no significant differences in PSV, EDV, and PI of the non-restenosis group between the 12-month observation period after procedure and one week after procedure (P >0.05). (2) The results of CDFI showed: PSV and EDV of the ipsilateral extracranial segment were improved significantly after procedure compare with those before procedure, they were 64 + 15 cm/s vs. 51 ±15 cm/s and 24 ± 6 cra/s vs. 19 ± 7 cm/s (all P < 0.05). The RI value and vertebral artery diameter of the extracranial segment were improved gradually, and they reached the peak at 12 months after procedure (0.61 ±0.07 is. 0.63 ±0.12, P =0.038; 3.6 ±0.4 mm vs. 3.4 ± 0.5 mm, P = 0.009). Conclusion CDFI in combination with TCCS can objectively evaluate the extra- and intracranial hemodynamic changes before and after IVA stenting, and provide reference information for the effectiveness of stenting and the imaging evaluation of restenosis.
The aim of this study was to evaluate the efficacy of stenting for patients with intra-cranial vertebral artery stenosis by trans-cranial color-coded sonography and to analyze the risk factors of in-stent restenosis (ISR). In total, 121 patients with intra-cranial vertebral artery stenosis stents were included. The follow-up time was 3-12 mo (mean: 9.9 mo). The success rate was 92.6%. Peak systolic velocity and end-diastolic velocity decreased from 261 ± 63 to 109 ± 41 cm/s and from 133 ± 44 to 47 ± 18 cm/s, respectively (both p < 0.001). Peak systolic velocity (245 ± 47 cm/s) and end-diastolic velocity (121 ± 31 cm/s) of patients with ISR (18.9%, 20/106) were higher than those of patients without ISR (101 ± 38 and 44 ± 17 cm/s, respectively) at 12 mo post-procedure (p < 0.05). The length of the stent and residual stenosis were related to ISR. In conclusion, stenting is a feasible treatment method for intra-cranial vertebral artery stenosis. Trans-cranial color-coded sonography can be used for monitoring patients to identify ISR.
