Color-coded Duplex Research Articles

Evaluation of cerebral autoregulation in dogs via transcranial color-coded duplex sonography and transient hyperemia testing.

To evaluate the changes in flow velocities of the middle cerebral artery before and after a carotid compression maneuver using transcranial color-coded duplex sonography (TCCD) in healthy anesthetized dogs under mechanical ventilation. Prospective study. University teaching hospital. Eleven healthy adult dogs. A 5-second carotid occlusion maneuver was performed to evaluate cerebral autoregulation (CA). After 10minutes of stable anesthesia, the middle cerebral artery was evaluated by TCCD. Dogs were positioned in sternal recumbency with the head raised to the level of the phlebostatic axis. The systolic peak velocity (Vp) was measured using pulsed Doppler mode. CA was evaluated through the transient hyperemia test (THT), which assesses changes in the Vp after a 5-second transient compression of the ipsilateral common carotid artery and is expressed as the ratio between the Vp flow before and after carotid compression. The Vp before and after carotid occlusion was compared using the Wilcoxon signed-rank test. The median Vp of the middle cerebral artery after the carotid compression maneuver was significantly higher than the median Vp before compression (median [interquartile range, IQR]: 47.7cm/s [34.3]vs64.1cm/s [24.4]; P=0.003). The median THT obtained was 1.20 (IQR: 0.37). The current study demonstrated a significant increase in the Vp of the middle cerebral artery after a 5-second temporary occlusion of the ipsilateral carotid artery in healthy anesthetized dogs under mechanical ventilation. These findings suggest that the noninvasive TCCD methodology could be valuable for assessing CA in dogs. Additional studies using this technique in neurocritical animals are required to confirm its usefulness.

Calcification is a risk factor for intracranial in-stent restenosis: an optical coherence tomography study

BackgroundThe frequent occurrence of calcification in intracranial artery stenosis increases the risk of ischemic stroke. In previous cases, we have observed a possible relationship between calcification and intracranial in-stent restenosis...

Point of Care Transcranial Color-Coded Duplex Ultrasound of the Middle Cerebral Artery.

In the assessment and management of many clinical problems, point-of-care (PoC) ultrasound is an emerging bedside tool. Transcranial color-coded duplex (TCCD) ultrasound can be valuable in multiple situations, including for patients who are unconscious or have an equivocal neurologic examination, as it helps rule in specific intracranial pathologies. Despite the known diagnostic value of transcranial ultrasound, its use in critical care medicine remains variable. This variability is partly due to inconsistent training across hospitals, stemming from a lack of standardized education and training. Additionally, the brain has often been overlooked in many critical care protocols, such as RUSH (Rapid Ultrasound for Shock and Hypotension) and FAST (Focused Assessment with Sonography in Trauma) exams. To address these gaps, this article proposes a protocol for PoC TCCD image acquisition in adults, detailing indications, limitations, transducer selection, placement, sequence acquisition, and image optimization. Furthermore, the use of PoC TCCD is discussed as a means of screening for three conditions: vasospasm, raised intracranial pressure, and progression of cerebral circulatory arrest.

High prevalence of intracranial arterial stenosis among acute ischemic stroke patients in a Brazilian center: a transcranial color-coded duplex sonography study.

There is limited data available regarding the prevalence of intracranial arterial stenosis (ICAS) among acute ischemic stroke (AIS) patients in Brazil and Latin America. The present study sought to investigate the frequency and predictors of ICAS among patients with AIS or transient ischemic attack (TIA) in a Brazilian center, with transcranial color-coded duplex sonography (TCCS) technique. Consecutive AIS and TIA patients, admitted to an academic public comprehensive stroke center in Brazil from February to December 2014, evaluated by TCCS were prospectively selected. Vascular narrowings > 50% were considered as ICAS, based on ultrasound criteria previously defined in the literature. We assessed 170 consecutive patients with AIS or TIA, of whom 27 (15.9%) were excluded due to an inadequate transtemporal acoustic bone window. We confirmed ICAS in 55 patients (38.5%). The most common location was the proximal segment of the middle cerebral artery (28.2%), followed by the vertebral (15.4%), posterior cerebral (13.6%), terminal internal carotid (9.1%) and basilar (8.2%) arteries. On multivariate models adjusting for potential confounders, systolic blood pressure (OR: 1.03, 95%CI: 1.01-1.04; p = 0.008) was independently associated with ICAS. We found significant ICAS in approximately ⅓ of patients admitted with symptoms of AIS or TIA in a public tertiary academic stroke center in Brazil. The TCCS is an accessible and noninvasive technique that can be used to investigate the presence of moderate and severe ICAS, especially in patients who cannot be exposed to more invasive exams, such as the use of intravenous contrast agents.

Guideline for the management of symptomatic and asymptomatic internal carotid artery stenosis

Stenoses of the internal carotid artery (ICA) with a≥ 50% degree of stenosis are common in the German population with aprevalence of approx. 4.2%. Furthermore, about 15% of ischemic strokes are due to stenosis or occlusion of the ICA. There are currently three approaches to the treatment of ICA stenoses: conventional therapy, endovascular treatment and surgical treatment. Summary of the S3guideline on the diagnosis, treatment and follow-up of extracranial carotid stenosis from 3February2020. Color-coded duplex sonography, computed tomography (CT) angiography and magnetic resonance (MR) angiography and, in exceptional cases, diagnostic subtraction angiography can be used to diagnose ICA stenoses, including the stenosis grade. The classification is into symptomatic and asymptomatic ICA stenoses. ICA stenoses can be treated conservatively, endovascularly with stenting or surgically by carotid endarterectomy. Invasive treatment should be carried out under inpatient conditions, whereby the hospital stay should be kept as short as possible. Color-coded duplex sonography should be performed regularly before discharge and at regular intervals thereafter to detect recurrent stenosis at an early stage and, if necessary, to initiate further invasive therapy. When choosing the treatment modality, particular attention must be paid to whether the stenosis is symptomatic or asymptomatic and the degree of stenosis. The S3guideline on the diagnosis, treatment and follow-up of extracranial carotid stenosis from 3February2020 provides guidance here.

Increases in Central Arterial Stiffness and Reductions in Diastolic Velocity in the Large Cerebral Arteries are Associated with Age-Related Decline in Cerebral Blood Flow

Background: Advanced aging is characterized by a reduction in cerebral blood flow (CBF) and an increase in central arterial stiffness. Increased central arterial stiffness results in reduced Windkessel effects and augmented pulsatile arterial blood pressure and CBF. These changes are detrimental to small cerebral blood vessels because of increases in biomechanical stresses associated with the augmented pulsatile arterial blood pressure and CBF. Purpose: To examine the associations of central arterial stiffness with cerebral hemodynamics and age-related reductions in CBF. Methods: 171 healthy subjects (20-81 yrs, 63% F) underwent color-coded duplex ultrasonography of the left and right internal carotid (ICA) and vertebral artery (VA) to characterize individual artery blood flow (BF), velocity, pulsatility, and CBF. Structural Magnetic Resonance Imaging (MRI) was used to measure total brain tissue volume (TBV). Carotid β-stiffness and carotid-femoral pulse wave velocity (cfPWV) were measured via applanation tonometry to assess central artery stiffness. Data: Age was negatively associated with global CBF (r = -0.425, p < 0.001), and positively with cfPWV (r = 0.701, p < 0.001), and carotid β-stiffness (r = 0.660, p < 0.001). Arterial stiffness was negative associated with ICA diastolic velocity (r = -0.280, p < 0.001; r = -0.259, p < 0.001) and VA diastolic velocity (r = -0.280, p < 0.001; r = -0.248, p = 0.001) controlling for sex, body mass index (BMI), education, and TBV. Carotid β-stiffness moderated indirect effect between age and CBF through ICA diastolic velocity (index of moderated-mediation -0.47 ± 0.13, [-0.74,-0.23]. cfPWV did not moderate the indirect effect between age and CBF through ICA diastolic velocity (index of moderated-mediation -0.36 ± 0.18, [-0.69, 0.03]. The indirect effect of age on CBF through VA diastolic velocity was not moderated by cfPWV (0.03 ± 0.09, [-0.13, 0.23]) or carotid β-stiffness (-0.17 ± 0.09, [-0.33, 0.01]). Conclusions: Age-related decline in CBF is mediated by the decreases in ICA blood flow diastolic velocity, and this relationship was moderated by carotid β-stiffness. This data suggests that increases in central arterial stiffness and reductions in CBF diastolic velocity in the large cerebral arteries likely plays an important role in age-related decline in CBF. This study was supported by NIH R01HL102457-01 and NIH R01AG033106-01. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

High-resolution ultrasound of thyroglossal cysts with special emphasis on the detection of cystic portions above the hyoid within the tongue base

Background: Thyroglossal duct cysts (TGDCs) within the tongue base represent a challenge for the surgeon and are often the cause of recurrence. Purpose: This study aimed to evaluate diagnostic performance of high-resolution ultrasound in TGDCs within the tongue base, compared to intraoperative findings. Furthermore, accuracy with which the detection of thyroid tissue in parts of the thyroglossal duct cyst was possible was investigated. Methods: A total of 50 patients with TGDCs were examined by high-resolution ultrasound. Every thyroglossal cystic lesion was examined for the presence of solid thyroid tissue with colour-coded duplex sonography and evaluated according to American Thyroid Association (ATA) guidelines. Ultimately, 45 of the 50 patients underwent surgery (Sistrunk procedure). Results: In 38/50 patients (76%), TGDCs were seen in their typical distal location inferior to the hyoid. Four patients (8%) had the thyroglossal duct cyst superior and inferior to the hyoid. The TGDC remnants only in the tongue base were recognised in 16% of cases (8 patients). Histological specimens revealed thyroid tissue within the TGDCs in 23 of the 45 patients (49%). Thyroid tissue was diagnosed preoperatively in 15 patients (65%) X2(1, N = 23) = 2.13, p = 0.144. One patient exhibited suspicious features for thyroid cancer, which was confirmed histologically as papillary thyroid carcinoma. Conclusion: High-resolution ultrasound represents quick, safe and reliable imaging for TGDCs on both sides of the hyoid bone (inferior and superior) with an impact on surgical planning. Furthermore, thyroid tissue within TGDCs can be revealed preoperatively and assessed for suspicious features.

Contrast-enhanced ultrasound evaluation of renal perfusion before angioplasty and its predictive value for hypertension.

Atherosclerotic renal artery stenosis (ARAS) is a common disease in the elderly population. The aim was to develop a contrast-enhanced ultrasound (CEUS)-based model for predicting post-angioplasty improvement in hypertension in patients with severe ARAS. Thirty-five patients with severe ARAS (⩾ 70%) were included in this study, and 42 renal arteries received percutaneous transluminal renal arterial stenting. An optimal integral formula was developed from pre-interventional color-coded duplex sonography (CCDS) and CEUS parameters using least absolute shrinkage and selection operator (LASSO) regression and receiver operating characteristic (ROC) curve analysis. A model for predicting short-term hypertension improvement was established using the integral formula and clinical risk factors. Bootstrapping was used for internal validation. Two integral formulas, LASSO.CCDS and LASSO.CEUS, were established. ROC curves of the two integral formulas showed that LASSO.CEUS was the better formula for predicting hypertension improvement (AUC 0.816, specificity 78.6%). Univariate and multivariate regression analyses showed that duration of hypertension (OR 0.841, P= 0.027), diabetes (OR = 0.019, P= 0.010), and LASSO.CEUS (OR 7.641, P= 0.052) were predictors of short-term hypertension improvement after interventional therapy. Using LASSO.CEUS combined with clinical risk factors, the following prediction model was established: logit (short-term improvement in hypertension) = 1.879-0.173 × hypertension duration - 3.961 × diabetes + 2.034 × LASSO.CEUS (AUC 0.939). The model established using CEUS parameters and clinical risk factors could predict hypertension improvement after interventional therapy, but further research and verification are needed.

Development of a prediction model for facilitating the clinical application of transcranial color-coded duplex ultrasonography

BackgroundTranscranial color-coded duplex ultrasonography (TCCD) is an important diagnostic tool in the investigation of cerebrovascular diseases. TCCD is often hampered by the temporal window that ultrasound cannot penetrate. Rapidly determine whether ultrasound can penetrate the temporal window in order to determine whether to use other acoustic windows to complete the examination process. In this study, Skull thickness can be measured simultaneously during TCCD examination, which makes it possible to use skull thickness to rapidly determine whether the temporal window is penetrated by ultrasound.MethodsThis retrospective study included 301 patients with clinical symptoms of cerebrovascular diseases. These 301 patients were divided into an impenetrable temporal window (ITW) group and a penetrable temporal window group according to the results of the TCCD examination.ResultsThe area under the receiver operating characteristic (ROC) curve (AUC) for skull thickness was 0.887 (cutoff value 1.045 cm). Following multivariate logistic regression, sex, age, and skull thickness were used to develop a nomogram. The AUC for the nomogram was 0.923 (cutoff value 0.407).ConclusionsThe skull thickness at the temporal window was measured by ultrasound, which was convenient and accurate. The probability of ITW in females was higher than that in males, and it increased with age. In this study, a prediction model incorporating sex, age and skull thickness could predict ITW probability well. If the patient’s temporal window was rapidly predicted as an ITW, other acoustic window examinations were used to complete the TCCD examination process to optimize the TCCD examination process of cerebrovascular diseases and facilitate the popularization of TCCD in clinical application.

First assessment of flow phenomena of acute and chronic thrombosis in the jugular veins using new ultrasound vector-flow imaging.

First assessment of flow changes in the jugular veins using high resolution ultrasound vector flow. 15 patients (8 males, 7 females) with an age range of 35 to 82 years (mean age 58.53±12.26 years) were examined by an experienced examiner using high power ultrasound equipment (Resona R9, Mindray) with probe technology (Mindray L9-3U Linear Array transducer, 2.5 to 9.0 MHz). This group was compared with five healthy subjects (mean age 35.4±13.79 years) as a reference. To assess flow changes, the color-coded duplex sonography and the novel vector flow technique were used. The evaluation was performed of vector morphology changes, turbulence, and wall resistance measurements. There were changes after acute and chronic thrombosis in 9 cases, and venous compression in 7 cases. Turbulence was measurable from 0.01 % to 64.44 %, the average turbulence was 19.73±22.06 %. Wall resistance measurement showed values from 0.01 Pa to 3.14 Pa, depending on the age of the thrombosis or compression. The reference veins showed turbulence of 0.94±1.5 % and a mean wall resistance of 0.05±0.05 Pa. There are statistically significant differences between normal and thrombotic or compressed veins in terms of maximum wall stress (p = 0.006) and mean degree of turbulence (p = 0.012), while the difference in mean wall stress is not statistically significant (p = 0.058). Despite still existing technical limitations, the combination of V-flow and wall stress measurements in jugular vein changes suggests a high diagnostic potential.

Initial description of the novel handheld wireless ultrasound device TE Air with Doppler and Color Duplex imaging.

To test and initially describe a new handheld wireless ultrasound technique (TE Air) for clinical use. In this pilot study, the new ultrasound device TE Air from Mindray was used to examine the hepatic and renal vessels of healthy volunteers for first impressions. The probe has a sector transducer with a frequency range of 1.8-4.5 MHz. The B-mode and color-coded doppler sonography (CCDS) scanning methods were used. A high-end device from the same company (Resona 9, Mindray) was used as a reference. The results were evaluated using an image rating scale ranging from 0 to 5, with 0 indicating not assessable and 5 indicating without limitations. Altogether, 61 participants (n = 34 female [55.7%], n = 27 male [44.3%]), age range 18-83 years, mean age 37.9±16.5 years) could be adequately studied using TE AIR and the high-end device. With one exception, the image quality score for TE Air never fell below 3 and had a mean/median scored of 4.97/5.00 for the B-mode, 4.92/5.00 for the color flow (CF) mode, and 4.89/5.00 for the pulse wave (PW) mode of the hepatic vein, 4.90/5.00 for the portal vein, 4.11/4.00 for the hepatic artery, and 4.57/5.00 for the renal segmental artery. A significant difference in the assessment of flow measurement of the hepatic artery and renal segmental arteries was found between TE AIR and the high-end device. TE Air represents a new dimension in point-of-care ultrasound via wireless handheld devices. Especially, its flow measurement ability offers a relevant advantage over other available handheld models. TE Air provides a formally sufficient image quality in terms of diagnostic significance.

Dynamic changes in glymphatic function in reversible cerebral vasoconstriction syndrome.

The pathophysiology of the reversible cerebral vasoconstriction syndrome (RCVS) remains enigmatic and the role of glymphatics in RCVS pathophysiology has not been evaluated. We aimed to investigate RCVS glymphatic dynamics and its clinical correlates. We prospectively evaluated the glymphatic function in RCVS patients, with RCVS subjects and healthy controls (HCs) recruited between August 2020 and November 2023, by calculating diffusion-tensor imaging along the perivascular space (DTI-ALPS) index under a 3-T MRI. Clinical and vascular (transcranial color-coded duplex sonography) investigations were conducted in RCVS subjects. RCVS participants were separated into acute (≤ 30days) and remission (≥ 90days) groups by disease onset to MRI interval. The time-trend, acute stage and longitudinal analyses of the DTI-ALPS index were conducted. Correlations between DTI-ALPS index and vascular and clinical parameters were performed. Bonferroni correction was applied to vascular investigations (q = 0.05/11). A total of 138 RCVS patients (mean age, 46.8years ± 11.8; 128 women) and 42 HCs (mean age, 46.0years ± 4.5; 35 women) were evaluated. Acute RCVS demonstrated lower DTI-ALPS index than HCs (p < 0.001) and remission RCVS (p < 0.001). A continuously increasing DTI-ALPS trend after disease onset was demonstrated. The DTI-ALPS was lower when the internal carotid arteries resistance index and six-item Headache Impact test scores were higher. In contrast, during 50-100days after disease onset, the DTI-ALPS index was higher when the middle cerebral artery flow velocity was higher. Glymphatic function in patients with RCVS exhibited a unique dynamic evolution that was temporally coupled to different vascular indices and headache-related disabilities along the disease course. These findings may provide novel insights into the complex interactions between glymphatic transport, vasomotor control and pain modulation.

The Role of Transcranial-Color-Doppler in the Management of Basilar Artery Stenosis: Case Series and Systematic Review of Literature

Managing vertebrobasilar (VB) stroke, particularly basilar artery occlusion (BAO), presents challenges due to diverse clinical presentations and intricate diagnostics, risking delays in acute-phase reperfusion therapies. The diagnostic complexities of VB stroke prompt questions about whether presentation tempo influences outcomes. For non-urgent cases of basilar artery stenosis (BAS) lacking guidelines, clinical management becomes case-dependent. Current options include aggressive medical therapy (AMT) and percutaneous transluminal angioplasty and/or stenting (PTAS). However, the choice of PTAS remains debated, with recent trials observing higher-than-expected recurrence rates, particularly in intracranial stenosis. Understanding hemodynamic status is crucial in predicting stroke risk, especially in atherosclerotic VB disease. Recent studies highlighted the role of distal flow status in predicting stroke risk, emphasizing the importance of hemodynamic assessment beyond anatomic measures. Neurosonology, especially transcranial color-coded duplex sonography (TCCS), emerges as a valuable tool for assessing hemodynamics. Despite TCCS being operator-dependent and technically challenging for BAS evaluation, it effectively detects significant hemodynamic changes, providing real-time information on collateral flow. This review explores the potential role of TCCS in managing BA hemodynamic failure in VB stroke, with particular regard to the selection of BAS patients who may benefit from PTAS.

Diagnosis and treatment of Dunbar syndrome

The rare Dunbar syndrome or medial arcuate ligament syndrome (MALS) is defined as compression of the celiac trunk and/or ganglion by the medial arcuate ligament. It is often diagnosed after patients have suffered for along time and is characterized by intermittent food-related pain, nausea, and unexplained weight loss. After exclusion of other causes of the above symptoms by gastroscopy, colonoscopy, CT, or MRI, the gold standard for diagnosis is dynamic color-coded duplex sonography, which may be supplemented by CT or MR angiography. The treatment of choice is alaparoscopic division of the arcuate ligament at the celiac trunk, although percutaneous transluminal angioplasty (PTA) with stent implantation may be performed in cases of postoperative persistence of symptoms or recurrent stenosis. Since symptoms persist postoperatively in up to 50% of cases, strict indication and complete diagnosis in designated centers are of great importance for successful treatment.

Equivalence in Color-coded Duplex Sonography Parameters before Complex Microsurgery.

Color-coded duplex sonography (CCDS) is a widely proposed noninvasive diagnostic tool in microsurgery. CCDS has been applied to lower extremity salvage cases to define appropriate blood flow velocity criteria for achieving arterial success in diabetic foot and complex microsurgery cases. This study aimed to compare the success ratio of free flaps when using CCDS versus cases where CCDS was not used. We included complex microsurgery cases from 2019 to 2021. These cases were subsequently categorized into two groups: group A consisted of cases where CCDS parameters were applied, whereas group B comprised cases where CCDS was not performed at all. The study encompassed 14 cases (11 men and three women). The age range varied from 23 to 62 years, with an average age of 42. Using CCDS analysis and planning demonstrated improved outcomes in comparison with cases where CCDS was not performed, albeit without statistical significance (P = 0.064). The application of CCDS proves to be beneficial in the realm of microsurgery. Although not achieving statistical significance, our data imply that CCDS utilization holds promise for enhancing microsurgical procedures.

The Diagnostic Performance of Multiparametric Ultrasound in the Qualitative Assessment of Inconclusive Cervical Lymph Nodes.

Enlarged cervical lymph nodes (CLNs) can result from infection or malignancies, and a definitive diagnosis requires histological examination. Ultrasound (US) remains the first-line imaging modality for detection, and new US techniques may improve characterization. The aim of our study was to investigate whether the qualitative assessment of multiparametric US (mpUS) can improve diagnostic performance in the differentiation of benign and malignant CLNs. 107 CLNs in 105 patients were examined by preoperative mpUS consisting of B-mode US, color-coded duplex sonography (CCDS), shear wave elastography (SWE) and contrast-enhanced US (CEUS). US images were evaluated in consensus by two experienced US operators. Histopathological examination was used as reference standard. SWE and CEUS combined showed the highest overall diagnostic performance (91% sensitivity, 77% specificity, 87% positive predictive value (PPV), 83% negative predictive value (NPV), 90% accuracy, χ2 (1) = 51.485, p < 0.001) compared to B-mode US and CCDS (87% sensitivity, 44% specificity, 73% PPV, 65% NPV, 73% accuracy χ2 (1) = 12.415, p < 0.001). In terms of individual techniques, SWE had higher specificity than B-mode and CCDS (71% sensitivity, 90% specificity, 92% PPV, 64% NPV, 78% accuracy, χ2 (1) = 36.115, p < 0.001), while qualitative CEUS showed the best diagnostic performance of all investigated US techniques (93% sensitivity, 85% specificity, 91% PPV, 87% NPV, 90% accuracy, χ2 (1) = 13.219, p < 0.001). Perfusion patterns, homogeneity, presence of necrosis, and malignancy differed significantly between malignant and benign CLNs (p < 0.001). SWE and CEUS can facilitate the differentiation of inconclusive CLNs when performed to supplement B-mode US and CCDS. MpUS may thus aid the decision between surgery and a watch-and-scan strategy in enlarged CLNs.

Retrospective study of spontaneous subarachnoid haemorrhage: vasospasm and other complications (Part III)

Background. Acute subarachnoid haemorrhage (SAH) is a dangerous condition: roughly 50% of patients die within 30 days, nearly 25% develop significant neuropsychological and cognitive deficits, about 10% suffer from other complications, and only around 15% recover fully. One of the main causes of mortality is cerebral vasospasm (CVS), a cause of delayed cerebral ischaemia (DCI), which can lead to secondary cerebral infarction. Thus, early detection of CVS is crucial for improving patient outcomes.The aim of this study was to analyse the demographic and clinical (including complications) data of patients diagnosed with SAH, to evaluate the diagnostic methods, and to investigate the prevalence and treatment of complications.Materials and methods. This retrospective study included 102 patients diagnosed with spontaneous SAH, aged at least 18 years, who were treated in the Vilnius University Hospital Santaros Klinikos (VUL SK) in 2014-2017. The obtained VUL SK data were selected by the I60 ICD-10-CM code and depersonalized. Head computerized tomography (CT), CT angiography (CTA), digital subtraction angiography (DSA), transcranial color-coded duplex sonography (TCCS), and magnetic resonance angiography (MRA) were used to evaluate the cerebral arteries.Results. In 102 patients (mean age 58±16 years; 55% female), the most common cause of spontaneous SAH was ruptured aneurysm, the most common arterial sites were the middle cerebral artery (36%), anterior cerebral artery and/or communicating artery (together 33%), and internal carotid artery (20%). In-hospital mortality was as high as 21%. All patients underwent head CT, 78% CTA, 33% DSA, 8% TCCS, and 1% MRA. 71% patients experienced SAH complications: 66% acute, 27% chronic. The most common acute complications were cerebral oedema (34%), rebleeding (29%), and acute ischaemia (23%), the most common chronic complications hydrocephalus (11%), DCI (9%), and CVS (8%).Conclusions. CVS was diagnosed considerably less frequently in this study compared to other studies. While the diagnosis rates of ischaemia and hyponatremia were likewise significantly lower in this study compared to those in others, they are in line with the CVS diagnosis rate. Aside from the CVS and CVS-related complications, all the other SAH complications were roughly within the range of the other studies.

Ultrasound assessment of brain supplying arteries (transcranial).

Ultrasonography of intracranial arteries is a non-invasive and highly efficient method for the diagnosis and follow-up of patients with cerebrovascular diseases, also in the bedside setting of the critically ill. For reliable assessment and interpretation of sonographic findings, the technique requires - apart from dedicated anatomic and pathophysiological knowledge of cerebral arteries and their hemodynamics - the comprehension of alternative imaging modalities such as CT or MR angiography. This article reviews the transcranial color-coded duplex sonographic (TCCS) examination technique including the transcranial Doppler sonography (TCD) for a standardized ultrasound assessment of the intracranial arteries and typical pathological cases. As a complementary tool, transorbital ultrasound for the assessment of the optic nerve sheath diameter and adjacent structures is also described in this article.

Detection of moderate to severe middle cerebral artery atherosclerotic stenosis in stroke patients: Transcranial color-coded duplex sonography versus computed tomography angiography.

Intracranial atherosclerotic stenosis is a common cause of ischemic cerebrovascular events and is associated with a high risk of stroke recurrence. This study aimed to assess the diagnostic accuracy of transcranial color-coded duplex sonography for moderate-to-severe middle cerebral artery stenosis in stroke patients. A retrospective analysis was carried out, including 31 patients aged ⩾18 years hospitalized for ischemic cerebrovascular event in whom middle cerebral artery stenosis ⩾30% was identified on computed tomography angiography. Transcranial color-coded duplex sonography findings were compared to the degree of stenosis blindly identified on the computed tomography angiography used as the reference method. Overall, 27 patients had M1 stenosis and the other 4 had M2 stenosis. To detect M2 stenosis ⩾ 50% and ⩾ 70%, stenotic to pre-stenotic ratio ⩾ 2 and ⩾ 3 had a sensitivity of 100%, respectively. To detect M1 stenosis ⩾ 70%, peak systolic velocity ⩾ 300 cm/s had a sensitivity of 53.8% and specificity of 85.7% with area under the receiver-operating characteristic curve of 0.753 (95% confidence interval: 0.568-0.938; p = 0.026), and stenotic to pre-stenotic ratio ⩾ 3 had a sensitivity of 84.6% and a specificity of 78.6% (area under the curve = 0.854; 95% confidence interval: 0.707-1; p = 0.002). Middle cerebral artery/anterior cerebral artery velocity ratio < 0.7 had a sensitivity of 57.1% and specificity of 90% to detect dampened pre-stenotic flow in middle cerebral artery secondary to downstream M1 stenosis ⩾ 70% (area under the curve = 0.800; 95% confidence interval: 0.584-1; p = 0.040). This study showed that stenotic to pre-stenotic ratio ⩾ 3 was more sensitive than peak systolic velocity ⩾ 300 cm/s to screen M1 stenosis ⩾ 70%. Middle cerebral artery/anterior cerebral artery ratio < 0.7 was a good indirect sign to detect dampened pre-stenotic flow due to M1 stenosis ⩾ 70%.

Impact of cerebral collateral flow on stroke outcomes after carotid stenting.

Internal carotid artery stenosis is a main contributor to recurrent ischemic stroke. This study aimed to evaluate associations between recurrent stroke and changes in prestenting flow direction in the primary collaterals or both primary and secondary collaterals, and the potential interaction between extra- and intracranial arteries. This longitudinal study recruited stroke patients without intracranial stenosis who underwent right-side carotid stenting between 2011 and 2019. The main study outcome was recurrent stroke. Predictive factors were anterior circulation flow direction change (ACFDC), posterior circulation flow direction change, and reversal of ophthalmic artery/leptomeningeal anastomosis (ROALA) detected by transcranial color-coded duplex (TCCD) before carotid stenting. Patient follow-up was 9 years. Risk factors for recurrent stroke were identified by Kaplan-Meier plot and Cox regression analyses. A total of 234 patients (mean age 70.88 ± 10.3 years, 86.32% male) were included, and 115 had recurrent stroke. Kaplan-Meier plot showed that patients with left ACFDC and ROALA had worse outcomes than those with ACFDC only, while patients with left ACFDC had worse outcome than those with right ACFDC (both p < 0.001). Cox regression analysis showed that recurrent stoke was associated with ACFDC at right (hazard ratio [95% CI]: 20.988 [2.549-172.790], p < 0.01), left (151.441 [20.100-1140.993], p < 0.001), and both sides (144.889 [19.089-1099.710], p < 0.001). Anterior circulation flow direction change is significantly associated with recurrent stroke in patients with unilateral carotid stenosis. Patients with ACFDC and ROALA together have worse outcomes compared to those with ACFDC only. Prestenting TCCD images help provide definitive information to predict outcomes after carotid stenting.