Number Of Arterial Feeders Research Articles

Angiographic predictors of spontaneous obliteration of transarterial partially embolized brain arteriovenous malformations.

Spontaneous obliteration of cerebral arteriovenous malformations is uncommon but could occur after partial embolization. A retrospective study of 140 patients that underwent embolization for cerebral AVMs from 2005 to August 2019 using liquid embolic agents. The angiographic outcome of patients was classified as regard complete embolization, partial embolization, and complete obliteration after partial embolization. The parameters studied included size, location, number of arterial feeders, number of draining veins, rupture status, embolic agent, and patient factors as well. The study patients included 74 (53%) females and 66 (47%) males. Their age ranged from 7 to 43 years old. One hundred and eight patients (77%) presented with hemorrhage. The AVM grades were grade II in 57 (40.7%) patients and grade III in 56 (39.3%) patients. Sixty-one (43.57%) patients were treated by n-Butyl Cyanoacrylate and 71 (50.71%) patients were treated with Onyx, and both materials were used together in 8 cases. Follow-up angiography was done from 6 to 36 months after embolization. The rate of complete occlusion in all patients was 61.43% (86 patients). There were three groups of patients, the first group had complete occlusion of the nidus at the time of embolization and included 68 (48.57%) patients. The second group had partial embolization with partial occlusion of the nidus 54 patients (38.57%). The 3rd group included 18 patients (12.85%) with complete nidal occlusion on follow up after partial embolization. The delay in the venous drainage of the AVM to the late arterial phase or early venous phase with flow stasis was a significant predictor of future obliteration on follow up after partial embolization. Other significant parameters that were associated with the progressive disappearance of the AVM nidus on follow up after partial embolization are presentation with hemorrhage, AVMs size less than 3 cm, the presence of single draining or double draining veins, superficial venous drainage, and one or 2 arterial feeders. Spontaneous closure of intracranial arteriovenous malformations after partial embolization may be encountered in cases of stasis of flow during embolization procedure with a delay of the venous drainage. A long-term follow-up of more cases over many years is required to confirm the validity of this conclusion.

The efficacy of TACE; how can automated feeder software help?

BackgroundThis is a prospective study of 44 patients having 57 hepatocellular carcinoma (HCC) lesions indicated for transarterial chemoembolization (TACE) and a control group of 41 patients having 55 HCC lesions. TACE in the study group was performed on an angiography machine with an installed automated feeder detection (AFD) software (EmboGuide; Philips Healthcare, Best, The Netherlands) and in the control group was performed on a similar angiography machine (ALLURA XPER FD 20, Philips, Holland), but lacking the AFD software. The aim is to evaluate the clinical utilization of cone-beam CT (CBCT) and (AFD) software in accurate detection of (HCC) arterial feeders, the effect of (AFD) software utilization on the outcome of (TACE) and its utilization effect on fluoroscopy time and radiation dose to the patient during the (TACE) procedure.ResultsThe highest percentage of agreement was between the number of arterial feeders detected by EmboGuide and the actual number of feeders detect during embolization reaching 91.2% with p value < 0.001. The residual non-intended non-embolized areas among the study group at 1-month follow-up were found in 2 out of 57 lesions compared to 9 out of 55 lesions in the control group. The average dose-area product (DAP) among the study group was less than that of the control group.ConclusionCBCT using AFD software provides more information about tumor feeders with consequent more efficient targeted embolization, higher success rate of TACE and less patient exposure to radiation.

Radiation Dose and Fluoroscopy Time of Endovascular Treatment in Patients with Intracranial Lateral Dural Arteriovenous Fistulae

PurposeIntracranial lateral dural arteriovenous fistula (LDAVF) represents a specific subtype of cerebrovascular fistulae, harboring a potentially life-threatening risk of brain hemorrhage. Fluoroscopically guided endovascular embolization is the therapeutic gold standard. We provide detailed dosimetry data to suggest novel diagnostic reference levels (DRL).MethodsRetrospective single-center study of LDAVFs treated between January 2014 and December 2019. Regarding dosimetry, the dose area product (DAP) and fluoroscopy time were analyzed for the following variables: Cognard scale grade, endovascular technique, angiographic outcome, and digital subtraction angiography (DSA) protocol.ResultsA total of 70 patients (19 female, median age 65 years) were included. Total median values for DAP and fluoroscopy time were 325 Gy cm2 (25%/75% percentile: 245/414 Gy cm2) and 110 min (68/142min), respectively. Neither median DAP nor fluoroscopy time were significantly different when comparing low-grade with high-grade LDAVF (Cognard I + IIa versus IIb–V; p > 0.05, each). Transvenous coil embolization yielded the lowest dosimetry values, with significantly lower median values when compared to a combined transarterial/transvenous technique (DAP 290 Gy cm2 versus 388 Gy cm2, p = 0.031; fluoroscopy time 85 min versus 170 min, p = 0.016). A significant positive correlation was found between number of arterial feeders treated by liquid embolization and both DAP (rs = 0.367; p = 0.010) and fluoroscopy time (rs = 0.295; p = 0.040). Complete LDAVF occlusion was associated with transvenous coiling (p = 0.001). A low-dose DSA protocol yielded a 20% reduction of DAP (p = 0.021).ConclusionThis LDAVF study suggests several local DRLs which varied substantially dependent on the endovascular technique and DSA protocol.

Angiographic factors associated with haemorrhagic presentation of brain arteriovenous malformation in a Chinese paediatric population.

To identify specific angiographic factors associated with haemorrhagic presentation of brain arteriovenous malformation in Chinese paediatric patients. Retrospective cross-sectional observational study. Four locoregional tertiary neurosurgical centres in Hong Kong: Queen Elizabeth Hospital, Tuen Mun Hospital, Kwong Wah Hospital, and Pamela Youde Nethersole Eastern Hospital. Patients aged 18 years or younger who underwent pretreatment digital subtraction angiography for brain arteriovenous malformation between 1 January 2005 and 31 July 2013 were included. Patients were divided into haemorrhagic and non-haemorrhagic groups based on the initial presentation. Pretreatment digital subtraction angiographies were independently reviewed by two experienced neuroradiologists. The following parameters were evaluated for their association with haemorrhagic presentation by univariate and multivariate analyses: nidus location, nidus size, nidus morphology (diffuse or compact); origin and number of arterial feeders; venous drainage; number of draining veins; presence of aneurysms, venous varices, and venous stenosis. A total of 67 children and adolescents (28 male, 39 female) with a mean age of 12 years were included. Of them, 52 (78%) presented with haemorrhage. Arteriovenous malformation size (P=0.004) and morphology (P=0.05) were found to be associated with haemorrhagic presentation by univariate analysis. Small arteriovenous malformation nidus size and diffuse nidal morphology were identified as independent risk factors for haemorrhage by multivariate analysis. Smaller arteriovenous malformation size and diffuse nidal morphology are angiographic factors independently associated with haemorrhagic presentation. Bleeding risk is important in determining the therapeutic approach (aggressive vs conservative) and timeframe, particularly in paediatric patients.

Cerebral arteriovenous malformations: influence of angioarchitecture on bleeding risk

To evaluate the angioarchitecture of cerebral arteriovenous malformations (cAVMs) with special regard to its influence on the risk of intracranial haemorrhage. Clinical and neuroradiological data of 171 patients with cAVMs, who were treated at our department, were analysed retrospectively. The angioarchitectonic data were obtained from angiographic series, cranial CT scans and MR images. A chi(2) test was conducted to correlate the parameters and determine the P values. The following parameters correlate to an increased risk of haemorrhage: diameter of the nidus < or =2 cm (P<0.001), number of arterial feeders < or =2 (P<0.001), diameter of the main feeder < or =1 mm (P<0.0001), number of veins draining the nidus < or =2 (P<0.001), exclusive deep drainage (P<0.05), and low or middle flow-velocity (P<0.01). Specific angioarchitectonic features such as venous stenoses, varicose dilatation of the draining vein, arterial aneurysms of the feeding artery, arteriovenous fistula within the nidus, contralateral drainage and sinushypo/-aplasia did not alter the bleeding rate. Various angiographic features were correlated with the occurrence of intracranial haemorrhage in patients with cerebral AVMs. In addition to the well-known factors influencing the bleeding risk of cAVMs like size, pattern of venous drainage and location within the brain our data demonstrate the importance to look at the diameter of the main feeder and the number of draining veins showing a better correlation.

Spontaneous regression of cerebral arteriovenous malformations: clinical and angiographic analysis with review of the literature.

Spontaneous regression of cerebral arteriovenous malformation (AVM) is rare and poorly understood. We reviewed the clinical and angiographic findings in patients who had spontaneous regression of cerebral AVMs to determine whether common features were present. The clinical and angiographic findings of four cases from our series and 29 cases from the literature were retrospectively reviewed. The clinical and angiographic features analyzed were: age at diagnosis, initial presentation, venous drainage pattern, number of draining veins, location of the AVM, number of arterial feeders, clinical events during the interval period to thrombosis, and interval period to spontaneous thrombosis. Common clinical and angiographic features of spontaneous regression of cerebral AVMs are: intracranial hemorrhage as an initial presentation, small AVMs, and a single draining vein. Spontaneous regression of cerebral AVMs can not be predicted by clinical or angiographic features, therefore it should not be considered as an option in cerebral AVM management, despite its proven occurrence.