Fig 1 - uploaded by Ross Naylor
Content may be subject to copyright.
(a) Intra-arterial digital subtraction angiogram (common carotid artery injection), showing two aneurysms at the bifurcation of the middle cerebral artery (arrowed). (b) Transcranial colour flow image in the axial plane of the basal cerebral vessels in the same patient as Fig. la. The left border is anterior, and the right border is posterior. The middle cerebral artery (MCA) up to its bifurcation can be imaged, but no aneurysmal sacs at this point can be visualised.
Source publication
Transcranial colour-coded sonography (TCCS) is a new development in noninvasive cerebral vascular imaging. We studied 5 patients with known intracranial aneurysms and 12 patients with arteriovenous malformations (AVM). We were unable to image any of the aneurysms (all 5 mm or less in diameter) using colour flow ultrasound. Similarly, pulsed wave Do...
Similar publications
Introduction:
Arteriovenous malformations (AVMs) are a type of vascular malformation characterised by an abnormal connection between arteries and veins, bypassing the capillary system. This absence of capillaries generates an elevated pressure (hyperdebit), in both the AVM and the venous drainage, increasing the risk of rupture. Management modalit...
Although diagnostic ureterorenoscopy is a minimally invasive and effective diagnostic procedure, it has the potential for significant postoperative complications. We report the first case in the literature of intrarenal arteriovenous fistulas causing hemodynamic effective anemia 4 days after ureterorenoscopic biopsy.
A 63-year-old Caucasian woman p...
Purpose:
The purpose of this study was to evaluate the diagnostic performance of non-contrast-enhanced magnetic resonance angiography with time-spatial labeling inversion pulse (time-SLIP MRA) in the assessment of pulmonary arteriovenous malformation (PAVM).
Methods:
Eleven consecutive patients with 38 documented PAVMs underwent time-SLIP MRA wi...
Radiosurgery is a recognized safe form of treating and usually curing arteriovenous malformations (AVMs). Complications related to radiosurgery, especially late sequelae, are rare. Such sequelae may be secondary to incomplete treatment of the original lesion such as haemorrhage, or secondary to the radiation damage to the tissue, or both. Sometimes...
Purpose. Arteriovenous malformations (AVMs) in the basal ganglia and thalamus have a more aggressive natural history with a higher morbidity and mortality than AVMs in other locations. Optimal treatment-complete obliteration without new neurological deficits-is often challenging. We present a patient with a large bilateral basal ganglia and thalami...
Citations
... These include difficulty delineating the boundaries of an artery and vein due to arterialization of the venous signal [24]. Another factor perhaps influencing the omission of venous flow characteristics from previous studies may relate to the lower velocity spectrum, and the close proximity to the arteries that display a more prominent signal [27]. Regardless of such mitigating factors, it remains a worthwhile consideration to attempt to include whatever hemodynamic data can be gleaned from the venous aspect of bAVMs, particularly in the postoperative phase. ...
Background:
Dramatic hemodynamic changes occur upon removal of an arteriovenous malformation of the brain (bAVM) with a number of potentially serious perioperative complications, such as intracranial hemorrhage and venous occlusive hypertensive syndrome. As these complications largely occur in the postoperative inpatient period, a rapid, repeatable noninvasive investigation to serially monitor relevant intracranial hemodynamics may be of benefit. Though, transcranial Doppler (TCD) and transcranial color duplex (TCCD) are techniques used and available to provide hemodynamic measurements postoperatively, the time course of hemodynamic sequences following bAVM resection remains uncertain.
Objective:
This is a prospective, case control pilot study conducted in participants having elective bAVM resection surgery.
Methods:
Each participant will undergo a preoperative color duplex ultrasound (CDU) of the bilateral extracranial carotid arteries, a CDU of the circle of Willis including the bAVM vessels, and a central aortic pressure measurement, repeated daily, postoperatively, for a 2-week period.
Results:
Patient accrual has commenced with anticipation of first results in 2018.
Conclusions:
This protocol aims to strengthen the work of previous authors by providing documentation of the time course of hemodynamic changes following bAVM resection. The protocol is designed to determine whether noninvasive technology, including CDU imaging of the extracranial carotid and intracranial arteries in the form of TCCD along with central aortic pressure measurements, can determine whether there are any hemodynamically significant prognostic markers that may provide insight into the process of vessel remodeling, including insight into venous changes following bAVM resection.
... Table 3 summarizes velocity and PI in AVM. Of note, an increased velocity and decreased resistance may be detected in the contralateral anterior cerebral artery, consistent with contribution via the anterior communicating artery [3][4][5]7,9,13,15,16,21,25,26]. ...
... The ratios in AVM ranged from 1.4:1 to 3.4:1 (median 2.1:1), significantly different to normal remote arteries with ratios of l.l:l to 2.1:1 (median 1.5:1) [12,25]. Relative flow velocities (RFV) and pulsatility transmission indices (PTI) initiated by Lindegaard and colleagues (n = 77) [27] were further replicated by Martin and colleagues (n = 12) [16] to give a more sensitive indication of which vessels are contributing to AVM blood supply than absolute velocity or PI. Variations greater than 0.2 (20%) for the RFV and 0.1 (10%) for the PTI were considered abnormal [27]. ...
... Variations greater than 0.2 (20%) for the RFV and 0.1 (10%) for the PTI were considered abnormal [27]. Although Lindegaard et al. considered the PTI more sensitive than the absolute PI for the diagnosis of AVM [27], Martin et al. found blood velocity asymmetry to be greatest when the end diastolic RFV was considered rather than the peak or mean RFV (Table 2) [16]. ...
Dramatic hemodynamic changes occur following resection of brain arteriovenous malformations (AVM). Transcranial Doppler (TCD) records non-invasive velocity and pulsatility parameters. We undertook a systematic review to assess AVM hemodynamics including the time course of changes in velocity and pulsatility in patients undergoing AVM resection. The review employed the Embase and Medline databases. A search strategy was designed. An initial title search for clinical series on AVM and TCD was performed followed by a search for reports on AVM and TCD. A total of 283 publications were selected. Full text analysis produced 54 studies with extractable data regarding AVM, velocity and pulsatility. Two TCD techniques were utilized: conventional “blind” TCD (blind TCD); and transcranial color duplex Doppler (TCCD). Of these, 23 publications reported on blind TCD and seven on TCCD. The presence of high velocity and low pulsatility within AVM feeding arteries preoperatively followed by a postoperative decrease in velocity and subsequent increase in pulsatility of feeding arteries is established. The time sequence of hemodynamic changes following AVM resection using TCD remains uncertain, confounded by variations in methodology and timing of perioperative measurements. Of the two techniques, TCCD reported qualitative aspects including improved differentiation of feeding arteries from draining veins. However, there are a limited number of studies supporting this conclusion. Furthermore, none report reproducible changes with time from treatment. TCCD appears to be a useful technique to analyze the hemodynamic changes occurring following treatment of AVM, however little data is available. This is a field of research that is appropriate to pursue.
... TCCS may be more cost effective in the surveillance of coiled intracranial aneurysms. TCCS can identify large and medium-sized intracranial aneurysms located in the proximal segments of the circle of Willis (90)(91)(92). Typically, an aneurysm is imaged as a pulsatile colored structure adjacent to the large parent artery. ...
... 89 Large and medium-sized cerebral aneurysms located in the proximal segments of the circle of Willis can be sometimes detected as colored oval structures of a pulsatile nature adjacent to large parent arteries. 90,91 Aneurysms located beyond the field of scanning and those that are thrombosed cannot be detected. The diagnostic accuracy of the TCCS assessment of AVMs using predefined criteria has not yet been investigated. ...
Transcranial color-coded duplex sonography (TCCS), in contrast to "blind" conventional transcranial Doppler sonography (TCD), enables a sonographer to outline the intracranial bony and parenchymal structures, visualize the basal cerebral arteries in color, and measure angle-corrected blood flow velocities in a specific site of the artery in question. This makes measurements of flow velocity more valid than those obtained with conventional TCD. TCCS is becoming a reliable tool for detecting the occlusion and narrowing of major intracranial arterial trunks. TCCS can image the collateral flow through the anterior and posterior communicating arteries in patients with unilateral, high-grade stenosis or occlusion of the extracranial internal carotid artery, without using potentially dangerous compression tests. Large and medium-sized arteriovenous malformations can also be detected with TCCS. The rapid sonographic assessment of cerebral hemodynamics in a neurosurgical patient with increased intracranial pressure can guide further management. The use of sonographic contrast agents can increase the number of conclusive TCCS studies in patients with insufficient acoustic windows.
... Comparison of the cerebral blood flow velocities on both sides is valuable for discovering abnormal vascular flow. Blood flow in the feeding vessels of an aneurysm is usually faster, but the RI and PI may be either lower or higher than in the contralateral normal vessels [2,11,12]. Vasospasm and collateral blood flow may be responsible for the high-velocity flow. The size of the aneurysm and the presence of thrombosis influence the RI and PI [2]. ...
A 4-month-old boy had a cerebral aneurysm detected on color Doppler sonography as a colorful cystic lesion at the junction of the right frontal and parietal lobes. Three-dimensional color Doppler sonography after the first operation revealed residual anomalous vessels related to the right middle cerebral artery. Blood flow in the feeding vessel was faster, but the resistance index and pulsatility index were lower than in the contralateral vessel. This case demonstrates that Doppler sonography is a valuable diagnostic technique for detecting intracranial aneurysms and for following any associated anomalies.
Brain arteriovenous malformation (bAVM) resection imposes several post-operative clinical challenges including intracranial haemorrhage (ICH). Daily non-invasive monitoring of haemodynamic measurements may be useful in predicting post-operative ICH.
This prospective study used transcranial colour duplex (TCCD) and central aortic pressure (CAP) measurements to evaluate 15 bAVM patients pre-operatively and daily ≤ 14 days post-operatively.
TCCD measurements of middle cerebral artery and veins included peak systolic (PSV), end diastolic (EDV), and pulsatility indices (PI). Parameters were compared with 7 craniotomy patients (non-bAVM craniotomy/surgical group). Normal reference values included 20 healthy volunteers.
Significant MCV changes in bAVM patients occurred;
Maximal PSV was significantly higher (median 47 cm/s) compared to non-bAVM craniotomy/surgical controls (median 17 cm/s, p = 0.0123); maximal PI was significantly higher (median 0.99, p = 0.005) compared to the non-bAVM craniotomy/surgical controls (median 0.49).
In 8 of 15 patients, increased MCV velocity and pulsatility “stabilised” within 14 days post-operatively. Mean number of days for the 8 patients to reach stable state was 5.9 days, (range 0–9 days).
To our knowledge, this is the first imaging study demonstrating significant venous changes post bAVM resection. Significant increased venous flow occurs in pial veins bilaterally. Increased pressure of venous flow is evidenced by a significant increase in diameter and pulsatility. Subsequently, haemorrhagic complications may be due distal constriction of the pial veins causing venous hypertension. The cause of the dilated vascular bed is unknown.
The ultrasound findings in a subject with cerebral venous thrombosis can be different according to the course of the disease over time, and therefore, also the role of neurosonological technique changes in the various stages. For both aspects, the acute phase and the follow-up can be distinguished.
Transcranial colour Doppler ultrasonography (TCCD), being a non-invasive method is an invaluable source of information on cerebral haemodynamics. It is the blood flow disturbances that often lead to irreversible ischemic lesions, which can then be detected a posteriori with various imaging techniques. From a therapy point of view, diagnosis after infarction has obvious limitations. Hence, the importance of transcranial colour Doppler ultrasonography, which can be used at the bedside and even in restless patients. The imaging of intracranial structures, however, is inferior to that of computed tomography and magnetic resonance. Nonetheless, TCCD ultrasonography is becoming a widely accepted tool in the diagnosis of acute and chronic ischemic stroke and cerebral vasospasm following subarachnoid haemorrhage. Rapid detection of critical impairment of cerebral blood flow in a neurosurgical patient could guide further management. Large and medium size arteriovenous malformations can also be evaluated with this method. Future developments of TCCD ultrasonography would make the method less operator-dependent and more reliable in obtaining information on cerebral circulation.
Innerhalb eines Zeitraumes von 15 Monaten wurden 88 Patienten mit 102 angiographisch nachgewiesenen intrakraniellen Aneurysmen unter Verwendung einer 2-MHz-Sonde mit der transkraniellen farbkodierten Duplexsonographie (TCCD) untersucht. Es wurden die Größe und der genaue Aneurysmasitz bestimmmt. Insgesamt konnten 70 (77%) Aneurysmen mit einem Durchmesser von 16±8 mm (6–55 mm) dargestellt werden. Eine sehr gute Darstellung der Aneurysmen gelang bei 36 (42%), eine mäßige bei 34 (40%) Aneurysmen, 16 (16%) Aneurysmen konnten trotz ausreichender Bildqualität nicht dargestellt werden. Bei weiteren 16 (16%) Aneurysmen war kein ausreichendes Knochenfenster vorhanden. Thrombosierte Anteile innerhalb der Aneurysmen konnten bei 16 (75%) von 20, der mit Coils behandelte Anteil bei 12 (48%) von 25 Aneurysmen erfolgreich dokumentiert werden. Die Methode ist zum Nachweis von teilthrombosierten Anteilen, von Behandlungserfolgen nach Coilembolisation und zur Verlaufskontrolle nicht behandelbarer Aneurysmen geeignet. Die Darstellbarkeit kleiner Aneurysmen ist begrenzt durch das Auflösungsvermögen und die teilweise ungünstigen Beschallungswinkel, somit eignet sich die TCCD nicht als Screeningmethode zum Nachweis von Aneurysmen.
