Intranidal Aneurysms Research Articles

Hypothesizing the interplay of thrombus formation, wall enhancement, and perifocal edema as predictive factors for rupture in brain AVMs

The presence of shear stress within intracranial AVMs (arteriovenous malformations) due to high flow, perinidal angiogenesis, intranidal aneurysms, and biological factors are presumed risk factors for rupture. However, emerging imaging and histological evidence suggests that risk factors for AVM rupture may extend beyond the classical understanding. The presence of perifocal edema at the time of rupture, luminal thrombosis, and vessel wall enhancement on vessel wall MRI elucidate the possibility of an underlying inflammatory process within AVMs, which may predispose them to instability and eventual rupture. We hypothesize that for some AVM ruptures, the occurrence of thrombosis within vascular outpouchings of the AVM initiates a cascade of events, including local hypoxia, inflammation, breakdown of the blood–brain barrier and wall matrix degradation, which is evident from the presence of perifocal edema and vessel wall enhancement observed on imaging. These changes might ultimately raise the risk of AVM rupture and subsequent hemorrhage. Understanding this inflammatory component offers promising insights into AVM pathogenesis and may facilitate the development of preventive strategies to mitigate rupture risk.

Arteriovenous malformation-associated aneurysms in the pediatric population: the University of Pittsburgh Medical Center experience.

Arteriovenous malformations (AVMs) are the most common cause of spontaneous intracranial hemorrhage (ICH) in children, often leading to devastating complications. The current literature from the adult AVM population suggests that both younger age and associated aneurysms carry an increased risk of hemorrhagic presentation. However, detailed analysis of pediatric AVM-associated aneurysms and their link to ICH is relatively unknown, with the literature largely consisting of case reports. This study aimed to determine whether AVM-associated aneurysms predispose pediatric patients to ICH. A retrospective cohort study of 238 pediatric patients with AVMs who presented to the Children's Hospital of Pittsburgh from 1988 to 2023 was performed. Hospital records, patient charts, and radiographic imaging studies were reviewed for patient demographic characteristics, presentation status, and AVM architecture. Of the 238 total patients, 44 (18.5%) children with AVM had associated aneurysms. There were 19 (38.8%) feeding artery aneurysms, 8 (16.3%) intranidal aneurysms, 21 (42.9%) postnidal aneurysms, and 1 (2.0%) unrelated aneurysm of 49 aneurysms. Five patients had venous varices. One hundred forty (58.8%) children presented with hemorrhage. Twenty-one of 44 (47.7%) patients with an AVM-associated aneurysm presented with hemorrhage, whereas 119 of 194 (61.3%) with a solitary AVM presented with hemorrhage (p = 0.10). On multivariate analysis, postnidal aneurysm (OR 0.36, p = 0.037) and an increased number of draining veins (OR 0.66, p = 0.049) were significantly associated with a decreased likelihood of hemorrhagic presentation. Deep venous drainage was associated with an increase in hemorrhagic presentation (OR 2.25, p = 0.0045) on multivariate analysis. Approximately one-fifth of children with AVMs in this study had accompanying aneurysms, and in this patient population, those with postnidal aneurysms and increased number of draining veins had a decreased incidence of hemorrhage on presentation. Feeding artery and intranidal aneurysms were not associated with an elevated risk of hemorrhagic presentation.

Embolization of midbrain arteriovenous malformation fed by the artery of Percheron in a child, the first case report and literature review.

Artery of Percheron (AOP) as main feeder artery of arteriovenous malformation (AVM) is extremely rare. Two cases of thalamic AVM fed by AOP have been reported to date and only one AVM been removed by microsurgery when attempt of intervention embolization failed. Midbrain AVM fed by AOP has not been reported yet. Here, we presented the first successful embolized case of midbrain AVM supplied by the AOP in a 10-year-old boy, who suffered dual oculomotor nerve palsy and secondary hemorrhage before embolization. During endovascular embolization, selective angiography by 1.2 Fr. Magic microcatheter showed an intranidal aneurysm located on the distal AOP. Two injections of a 1:4 ratio mixture of NBCA-MS completely occlude the nidus and intranidal aneurysm with no complications occurred. The child recovered well and the oculomotor deficits improved. This case highlighted that AOP is a clinically significant branch associated with AVM in midbrain and thalamus. Moreover, intervention embolization of midbrain AVM fed by AOP is a considerable therapeutic strategy.

196 Increased Hemorrhage Risk With Brain AVM-Associated Aneurysms in Children

INTRODUCTION: Brain arteriovenous malformations (AVMs) represent a major cause of intracranial hemorrhage with pediatric patients at greater lifetime risk of rupture compared to their adult counterparts. These AVMs can be associated with aneurysms that are either arterial or intranidal. The significance of AVM-associated aneurysms in the pediatric population remains poorly understood due to their rare nature and spare reporting. METHODS: We reviewed a prospectively maintained database of pediatric brain AVMs from 1998 to 2021 at the University of California, San Francisco. Inclusion criteria included patients with age ≤ 18 at time of presentation with angiographically-proven AVM. RESULTS: Of 231 patients with AVMs, 24 patients harbored 35 arterial aneurysms, and 35 patients harbored 38 intranidal aneurysms. Compared to AVMs without aneurysms with a mean nidus size of 3.02 ± 1.74 cm, AVMs with intranidal aneurysms had a significantly smaller mean nidus size at 2.13 ± 1.12 cm (p = 0.004). AVMs with intranidal aneurysms had a higher proportion of being ruptured on presentation compared to AVMs without aneurysms (94% vs. 59%, p < 0.001). AVMs with intranidal and arterial aneurysms also underwent higher proportions of surgical resection (92% and 80% vs. 59%, p = 0.001) and embolization (37% and 50% vs. 25%, p = 0.022) with higher rates of nidus obliteration (91% and 79% vs. 65%, p = 0.005). In those that were not obliterated, AVMs with intranidal and arterial aneurysms have higher annual hemorrhage risks (10.2% and 7.4% vs. 1.6%) after patient presentation. Patients who underwent a hemorrhage event after presentation had a higher proportion of worsened clinical status compared to presentation (38% vs. 5.6%, p < 0.001). CONCLUSIONS: A higher proportion of AVMs with associated aneurysms present with hemorrhage and are more likely to undergo additional hemorrhage events when incompletely treated compared to AVMs without aneurysms.

Abstract Number ‐ 210: Curative Embolization of Ruptured Pediatric Cerebral Arteriovenous Malformations

Introduction The incidence of ruptured cerebral arteriovenous malformations (AVMs) has increased as a consequence of the publication of the ARUBA trial. In the setting of ruptured AVMs, target embolization of high‐risk features can be considered to decrease the risk for recurrent hemorrhage. However, embolization with the intention to cure has not been well studied in ruptured AVMs. Furthermore, the role of primary curative embolization of pediatric AVMs is uncertain. Hence, we aimed to characterize the safety and efficacy of curative embolization for ruptured AVMs in pediatric patients. Methods Between 2010 and 2022, a retrospective analysis of all pediatric (≤18 years) patients who underwent curative embolization for ruptured AVMs was conducted in two institutions. Demographic data, clinical presentation, Spetzler‐Martin (SM) grade, associated high‐risk vascular structures, and procedural characteristics were retrieved. The safety (intraprocedural complications and mortality) and efficacy (complete angiographic obliteration after the last embolization session) were evaluated. Results Sixty‐eight patients (38 females; mean age 12.4 ± 3.4 years) underwent a total of 109 embolization sessions. The most frequent clinical presentation was headache (79%). There were 15 (22%) SM grade I lesions, 34 (51%) grade II, 14 (21%) grade III, and 4 (6%) grade IV. In 21 patients, twenty‐three high‐risk structures were observed (3 prenidal aneurysms, 12 intranidal aneurysms, 3 venous aneurysms, 2 varicose veins, 3 arteriovenous fistulae). Decompressive craniectomy with intracerebral hemorrhage evacuation was performed in 15 patients (22%). The mean number of sessions per patient was 1.6 (range 1 to 6) and n‐butyl cyanoacrylate was the most used embolic agent (30%). The transarterial approach was the most common (91%). The mean volume of embolic agents in each patient was 2.1 ml (range 0.1 to 6 ml). Seventeen intraprocedural complications (16% of procedures) were observed and no deaths were reported. In patients with high‐risk structures the rate of intraprocedural complications was 24%. The most common complication was microcatheter‐related vessel perforation (7%). Complete angiographic obliteration was achieved in 42 patients (62%). In 30 patients (44%) the AVM was occluded with a single embolization session. The rate of complete obliteration in patients with high‐risk structures was 62%. Conclusions Curative embolization of ruptured pediatric AVMs shows a high rate of intraprocedural complications, especially when high‐risk associated vascular structures are present. In addition, acceptable complete obliteration rates were found. Appropriate long‐term follow‐up in prospective studies tailored to the pediatric population are required to determine the best therapeutic approach.

Efficacy of Liquid Embolic Agent Treatment in Hemorrhagic Peripheral Intracranial Aneurysms: A Single-Center Experience.

Objective: To evaluate the efficacy of liquid embolization agents for treating various hemorrhagic peripheral intracranial aneurysms. Methods: We retrospectively analyzed 38 patients who suffered from hemorrhagic peripheral intracranial aneurysms and were treated with liquid embolization agents. We used the modified Rankin scale for follow-up at 6 months postoperatively, and digital subtraction angiography follow-up was performed 6 months postoperatively. Results: Of the 38 patients (ten of simple peripheral intracranial aneurysms, six of Moyamoya disease (MMD), and 22 of arteriovenous malformation (AVM)), posterior circulation accounted for the most significant proportion (57.9%), followed by anterior circulation (21.1%) and intranidal aneurysms (21.1%). Intraoperative hemorrhage occurred in four cases, postoperative cerebral infarction occurred in four cases, two patients encountered microcatheter retention, and intraoperative thrombosis took place in the basilar artery of a patient with an arteriovenous malformation. A postoperative hemorrhage occurred in only one patient. At 6-month follow-up, 84.2% of patients had good prognosis outcomes, and 13.5% had poor outcomes. Conclusion: Liquid embolization agents are effective for hemorrhagic peripheral intracranial aneurysms; however, safety depends on the subtypes. For peripheral hemorrhagic aneurysms in MMD, the vessel architecture must be carefully evaluated before embolization.

A Prospective Study Comparing the Three-Dimensional Rotational Angiography and Two-Dimensional Digital Subtraction Angiography in Evaluation of Brain Arteriovenous Malformations.

Complex angioarchitecture of brain arteriovenous malformations (BAVM) are often difficult to evaluate with standard imaging technique of digital subtraction angiography (DSA). These details are better provided by 3D rotational angiography (3D-RA). The aim of the study is to compare two-dimensional digital subtraction angiography (2D-DSA) and 3D rotational angiography in the evaluation of BAVM angiographic architecture. 2D-DSA and 3D-RA of 167 consecutive patients with BAVM were analyzed for arterial feeders, nidal patterns, and detection of flow-related aneurysms, arteriovenous fistulous components, venous drainage, and draining vein stenosis. 3D-RA detected a significantly higher number of aneurysms and draining venous stenoses (P < 0.001). The detected number of true intranidal aneurysms was significantly higher with 3D-RA (n = 94) vs 2D-DSA (n = 34) (P < 0.001). 2D-DSA has low sensitivity (43.1%) and specificity (73.4%) for detecting intranidal aneurysms. 3D-RA detected a significantly higher number (12.6%) of BAVM patients with feeding artery aneurysms as compared to 2D-DSA (8.4%), P value of 0.004. 3D-RA accurately depicted the distal course of dominant arterial feeders and fistulous sites in BAVMs. Direct arteriovenous communications were evident in 31.1% with 3D-RA, as compared to 2D-DSA (15%) with P value < 0.0001. A significantly higher number of draining vein stenosis was detected with 3D-RA (21.6%) as compared to 2D-DSA (13.2%), P value < 0.001. 3D-RA is better than 2D-DSA for detecting BAVM-associated flow-related aneurysms, distal course of the dominant arterial feeders, direct visualization of the fistulous components, deep venous drainage, and draining venous stenosis; findings imperative for making a prudent therapeutic decision.

Evaluation of theTherapeutic Effect of the Hybrid Operation on Patients with Aneurysms Associated with Cerebral Arteriovenous Malformations with different Redekop Classifications

BackgroundIntracranial aneurysms associated with cerebral arteriovenous malformations (AVMs) are a rare condition in the clinic, and treatment is very difficult due to their particular anatomical features. We present our experience in the treatment of intracranial aneurysms with AVMs and evaluate the effectiveness and safety of endovascular treatment combined with microsurgical resection (the hybrid operation). MethodsThis was a single-center retrospective study in our neurosurgical department from January 2015 to January 2021. We collected clinical data from 48 patients with intracranial aneurysms associated with AVMs and categorized them according to Redekop classifications according to the results of cerebral imaging examination to compare the therapeutic effects of endovascular embolization and the hybrid operation. ResultsCompared to nonaneurysmal AVMs, intracranial aneurysms with AVMs more often presented with intracranial hemorrhage (P<0.05). Massive hematoma and severe neurological impairment were more often found in patients with intracranial aneurysms with AVMs (P<0.05). For flow-related aneurysms, the hybrid surgery had a higher one-stage cure rate than endovascular embolization alone (P<0.05). Both treatment methods had similar effects on intranidal aneurysms (P>0.05). There were no significant differences in prognostic indicators between the two treatments. However, the recurrence rate of AVMs with proximal flow-related aneurysms was lower in patients who underwent the hybrid operation (P<0.05). ConclusionThe hybrid operation was safe and effective for patients with intracranial aneurysms associated with AVMs. For flow-related aneurysms, the one-stage cure rate was higher and the recurrence rate was lower with the hybrid operation than with endovascular embolization alone.

Stereotactic radiosurgery for ruptured versus unruptured intracranial arteriovenous malformations.

Background: There are a limited data examining the effects of prior hemorrhage on outcomes after stereotactic radiosurgery (SRS). The goal of this study was to identify risk factors for arteriovenous malformation (AVM) rupture and compare outcomes, including post-SRS hemorrhage, between patients presenting with ruptured and unruptured AVMs.Methods: A retrospective review of consecutive patients undergoing SRS for intracranial AVMs between 2009 and 2019 at our institution was conducted. Chi-square and multivariable logistic regression analyses were utilized to identify patient and AVM factors associated with AVM rupture at presentation and outcomes after SRS including the development of recurrent hemorrhage in both ruptured and unruptured groups.Results: Of 210 consecutive patients with intracranial AVMs treated with SRS, 73 patients (34.8%) presented with AVM rupture. Factors associated with AVM rupture included smaller AVM diameter, deep venous drainage, cerebellar location, and the presence of intranidal aneurysms (P < 0.05). In 188 patients with adequate follow-up time (mean 42.7 months), the overall post-SRS hemorrhage rate was 8.5% and was not significantly different between ruptured and unruptured groups (10.3 vs. 7.5%, P = 0.51). There were no significant differences in obliteration rate, time to obliteration, or adverse effects requiring surgery or steroids between unruptured and ruptured groups.Conclusion: Smaller AVM size, deep venous drainage, and associated intranidal aneurysms were associated with rupture at presentation. AVM rupture at presentation was not associated with an increased risk of recurrent hemorrhage or other complication after SRS when compared to unruptured AVM presentation. Obliteration rates were similar between ruptured and unruptured groups.

Case Series for Gamma Knife Surgery for Arteriovenous Malformation Associated Intracranial Aneurysms

Abstract Objective The incidence of aneurysms coexisting with arteriovenous malformations (AVMs) ranges between 2.7% and 16.7%. The anatomical relationship between AVM and aneurysm is critical in deciding the best management. Methods Between October 1994 and August 2017, gamma knife surgery (GKS) was performed in six patients with AVMs and associated aneurysms. The patients consisted of four men and two women with a mean age of 37.8 years (range, 18−57 years). The mean follow-up was 34.2 months (range, 13−84 months). The mean maximal dose was 35.9 Gy and the mean margin dose to AVM was 18 Gy. Coil embolization was performed in one of the aneurysms prior to GKS. In our study, GKS was performed in six AVM-associated aneurysms. Of the six aneurysms, four were intranidal and two were pedicular. The mean volume of AVMs was 3.6 cm3 (range, 1.6−6.5 cm3). Results The locations of aneurysms are as follows: four on posterior cerebral artery (PCA), one on posterior inferior cerebellar artery (PICA), and one on middle cerebral artery (MCA). Sublocation sites were MCA M3 above, PCA P3 above, and PICA distal. There were no GKS-related complications. Complete obliteration of AVM and aneurysm was documented in all four patients with intranidal aneurysm-associated AVMs. Both the aneurysm and AVM were completely obliterated in the two patients with proximal pedicular aneurysms. Conclusion GKS is a possible treatment for AVM with associated intranidal or pedicular aneurysms located above P3 or M3, etc., in which there is less turbulent flow and jet flow.

Endovascular treatment of aneurysms associated with cerebral arteriovenous malformations

To evaluate treatment outcomes in 120 patients with AVM-associated aneurysms. We analyzed treatment outcomes in 639 patients with cerebral AVM who underwent 1992 endovascular procedures between 2010 and 2019. AVM-associated aneurysms were found in 120 (18.8%) cases: 81 (67.5%) patients with 69 proximal and 29 distal aneurysms, 33 (27.5%) AVMs with intranidal aneurysms and 6 (5%) aneurysms without hemodynamic connection with AVM. One hundred and one malformations (16.9%) out of 596 supratentorial AVMs and 19 (44.2%) out of 43 subtentorial AVMs were associated with aneurysms. Intracranial hemorrhage occurred in 349 (53.3%) out of 639 patients with AVM: 97 (80.8%) out of 120 patients with AVM-associated aneurysms and 252 (48.6%) out of 519 ones with AVM and no aneurysms. All 33 patients with intranidal aneurysms in the AVM structure and 18 (94.7%) out of 19 patients with AVM-associated aneurysms and AVM in posterior cranial fossa had intracranial hemorrhage. There were 98 aneurysms in 81 patients with AVM-associated aneurysms. Eighty-nine (90.8%) ones underwent endovascular treatment, 6 (6.1%) patients with proximal aneurysms required microsurgery. Three distal aneurysms were not repaired. Thirty-four aneurysms were embolized with spirals. Embolization with spirals and balloon assistance was performed for 41 aneurysms, spirals with stent-assistance - for 9 aneurysms (including 1 distal MCA aneurysm in hemorrhagic period). Implantation of a flow-diverting stent was performed for 5 aneurysms (1 distal and 4 proximal aneurysms). There were 8 (8.9%) complications after embolization of 89 AVM-associated aneurysms (5 thromboembolic and 3 hemorrhagic events). According to our data, intranidal aneurysms require exclusion of the parent AVM segment due to high risk of hemorrhage. Treatment of proximal AVM-associated aneurysms should be carried out prior to AVM embolization. Distal aneurysms do not regress after definitive AVM treatment and should be operated on after total AVM embolization.

Single-center experience with endovascular treatment of cerebral arteriovenous malformations with intent to cure in pediatric patients.

This study aimed to report the incidence of technical complications and immediate complete angiographic occlusion, identify associated factors with failure of complete occlusion and identify predictors of technical complications in a single-center experience of pediatric arteriovenous malformations (AVM) treated with endovascular treatment with intent to cure. Patients between 1 and 18years of age undergoing endovascular embolization between 2011 and 2020 were included. A total of 120 embolizations were performed in 69 patients. The most frequent clinical presentation was intracerebral hemorrhage (76.8%). Immediate obliteration of the malformations was achieved in 40 (58%) cases. The technical complication rate was 15%. AVM nidus size between 3 and 6cm (OR: 3.91; 95% CI 1.1-13.85; p = 0.035) and the presence of multiple feeders (OR: 5.08; 95% CI 1.41-18.28; p = 0.074) were predictive of failure of immediate complete occlusion. The location of the temporal lobe (OR: 7.83; p = 0.048), deep venous drainage (OR: 4.67; p = 0.112), and the presence of an intranidal aneurysm (OR: 3.58; p = 0.134) were predictors of technical complications. Embolization of pediatric AVMs with intent to cure shows a high rate of technical complications and acceptable immediate occlusion rates. Nidus size and the presence of multiple feeders were predictive of failure of complete occlusion, while temporal lobe location, deep venous drainage, and the presence of an intranidal aneurysm were predictors of technical complications. Further studies are needed to determine the best therapeutic approach in the pediatric population.

Clinical and Angioarchitectural Features of Hemorrhagic Brain Arterio-Venous Malformations in Adults and Children: Contrasts and Implications on Outcome.

Hemorrhage from brain arteriovenous malformations (bAVMs) is estimated at 3% per annum. Features influencing risk of hemorrhage include perforator/posterior circulation supply, associated aneurysms, and deep drainage. Children are more likely to present with bAVM bleeds. To analyze differences in bAVM angioarchitecture between children and adults and describe predictors of poor outcome. Data were collected from adult and pediatric tertiary referral hospitals. Demographic data, bleed location, treatment, and follow-up modified Rankin Scale (mRS) were collected. Angioarchitectural assessment included aneurysm presence, nidus morphology, perinidal angiogenesis, intranidal shunting, steal phenomenon, venous ectasia, venous stenosis, venous reflux, and pseudophlebitic pattern. Regression analyses conducted to determine predictors of mRS>2. A total of 270 adult and 135 pediatric ruptured bAVMs were assessed. Median age was 42 (adults) and 10.9 (children) yr. Intranidal aneurysms were more frequent in children (P=.012), whereas prenidal aneurysms were more common in adults (P<.01). Children demonstrated more perinidal angiogenesis (P=.04), whereas steal phenomenon was commoner in adults (P<.01). Venous ectasia (P<.01), reflux (P<.01), and pseudophlebitic pattern (P=.012) were more frequent in adults. Children had better outcome (mRS score≤2) (P<.01). Older age (odds ratio [OR]=1.02), eloquent location (OR=2.5), multicompartmental hemorrhage (OR=1.98), venous reflux (OR=2.5), diffuse nidus (OR=1.83), pseudophlebitic pattern (OR=1.96), intranidal shunts (OR=2), and no treatment (OR=3.68) were significant predictors of mRS>2. Children are more likely to have intranidal aneurysms and perinidal angiogenesis, whereas adults have more prenidal aneurysms, venous ectasia, corticovenous reflux, and pseudophlebitic pattern. Eloquent location, diffuse nidus, intranidal shunts, venous reflux, and pseudophlebitic pattern predict poorer outcome.

Imaging characteristics and endovascular treatment strategy for cerebellar arteriovenous malformations.

Cerebellar arteriovenous malformations (CAVMs) have increased probabilities of rupture and bleeding compared with arteriovenous malformations (AVMs) in other locations of the brain. Endovascular treatment (EVT) for CAVMs is difficult; as the angioarchitecture of CAVMs is complex, EVT may be associated with complications, due to the involvement of crucial structures, such as the brainstem. The present study aimed to determine the efficacy of EVT for CAVMS. For this purpose, 33 cases of CAVMs treated with EVT from January, 2015 to January, 2020 were retrospectively analyzed. The 33 patients were aged 8 to 73 years (mean age, 40.4±17.8 years) and 21 were female (63%, 21/33). Rupture and bleeding occurred in 29 patients (87.9%, 29/33). Among the 33 CAVM cases, 15 (45.5%, 15/33) were fed by a single artery, and 18 (54.5%, 18/33) were fed by multiple arteries. In total, 27 patients (81.8%, 27/33) had superficial vein drainage alone. Among the 33 cases, 15 were complicated by 16 aneurysms, including 14 prenidal aneurysms and 2 intranidal aneurysms. Among the 33 cases, the nidus of the CAVM (87.9%, 29/33) was treated with Onyx™ casting in 29 patients: 8 cases (27.6%, 8/29) had an embolization volume of <1/3 of the nidus, 11 cases had a volume of 1/3-2/3 of the nidus (37.9%, 11/29) and 10 cases had a volume >2/3 of the nidus (34.5%, 10/29). Among the EVT complications, there were 3 cases (9.1%, 3/33) of intraoperative and post-operative bleeding, which resulted in two deaths (on the 1st and 7th days). The length of hospital stay was 10.7±5.4 days. In total, 27 patients (81.7%, 27/33) had a Glasgow Outcome Scale (GOS) score of 5 at discharge. On the whole, the present study demonstrates that overall, EVT is a feasible treatment for CAVM and may be used to obtain acceptable therapeutic effects.

Spontaneous cerebral SAH by intranidal aneurysm rupture of cervical intramedullary glomus arteriovenous malformation: case report and review of the literature

Spontaneous cerebral SAH by intranidal aneurysm rupture of cervical intramedullary glomus arteriovenous malformation: case report and review of the literature

Stagnant venous outflow in ruptured arteriovenous malformations revealed by delayed quantitative digital subtraction angiography

PurposeTo investigate the reproducibility of quantitative digital subtraction angiography (QDSA) measurements and their associations with brain arteriovenous malformation (BAVM) hemorrhage. MethodsFrom 2011–2019, 37 patients with BAVMs who had undergone both diagnostic and stereotactic DSA were divided into hemorrhagic and nonhemorrhagic groups. QDSA analysis was performed on the 2 DSA exams. The inter-exam reliabilities of QDSA measurements across the diagnostic and stereotactic DSA were tested using intraclass correlation coefficients (ICCs). Demographics, BAVM characteristics, and QDSA results for the hemorrhagic and nonhemorrhagic groups were compared. ResultsFifteen of 37 (40.5 %) patients presented with hemorrhage were associated with smaller BAVM volume and the presence of intranidal aneurysm and exclusive deep venous drainage. The median interval between the diagnostic and stereotactic DSA was 49 days and did not differ between the groups. In both groups, the inter-exam QDSA measurements were more reliable for drainage veins and transnidal time (ICCs ranged from 0.38–0.93) than for feeding arteries (ICCs ranged from 0.01–0.74). Among the venous parameters, the hemorrhagic group had lower peak density, area under the curve, inflow gradient, and outflow gradient on both DSA exams and larger full width at half maximum and stasis index on the stereotactic DSA exam than the nonhemorrhagic group. ConclusionsIn BAVMs, the QDSA measurements for veins are more reliable than those for arteries. QDSA analysis reflecting stagnant venous drainage is associated with BAVM hemorrhage, but may be confounded by the acute hemodynamic change after hemorrhage.

AN UNUSUAL SUSPECT: A CASE OF DELAYED CEREBRAL INFARCTS FROM VASOSPASM AFTER A RUPTURED ATERIOVENOUS MALFORMATION

SESSION TITLE: Fellows Critical Care Posters SESSION TYPE: Fellow Case Report Posters PRESENTED ON: October 18-21, 2020 INTRODUCTION: Subarachnoid hemorrhages (SAH) affect roughly 1 in 10,000 adults annually, with roughly 50% resulting in death soon after development. The majority of the cases are the result of an aneurysm rupture but rarely, can be caused by arteriovenous malformations (AVM’s). The leading cause of morbidity after surviving an SAH is the neurologic deterioration that occurs from delayed cerebral ischemia (DCI) and infarction as a result of vasospasm. AVM’s have only recently been gaining recognition as a cause of clinical deterioration from DCI’s. CASE PRESENTATION: Patient is a 41 yo female with no past medical history who initially presented with complaints of the worst headache of her life. Imaging revealed intraventricular hemorrhage (IVH) with subarachnoid hemorrhage, attributed to a ruptured AVM. CT angiogram showed a left parietal occipital AVM with associated intra-nidal aneurysms. Patient underwent embolization of the AVM and nidal aneurysms. Due to the morphology of the AVM, patient underwent a debulking and resection of the AVM with evacuation of the left IVH. Post-operative course was complicated by acute neurological change (unresponsive, minimal extremity motor exam). Imaging showed new changes consistent with an acute infarct and bilateral narrowing of the anterior and middle cerebral arteries, secondary to vasospasm. She subsequently required multiple intra-arterial treatments with verapamil. Her neurological exam slightly improved with treatments and was subsequently discharged to a long-term acute care facility for therapy. DISCUSSION: Unlike aneurysm rupture, cerebral vasospasm after a ruptured AVM is rarely reported and often not recognized as a cause of delayed cerebral ischemia. This could lead to clinical decline and should be considered in the differentials of neurological deterioration following the hemorrhage of an AVM. A recent retrospective analysis revealed that the SAH component and infratentorial location of a rupture AVM may have a higher risk for cerebral vasospasms and recommended follow-up angiographic imaging in patients with neurological deterioration. However, there currently is no recommendation for empiric delayed angiography to assess for vasospasms after a ruptured AVM. CONCLUSIONS: Despite the robust evidence-based guidelines on the comprehensive management of SAH from aneurysm ruptures, including the management of cerebral vasospasm and DCI, there is no such guideline for ruptured AVM’s. In the setting of acute neurological deterioration after treatment of an AVM (via resection or embolization), assessment for cerebral vasospasm and DCI should be considered. Reference #1: Goss BA, Du R. Vasospasm after arteriovenous malformation rupture. World Neurosurg. ;Sep-Oct;78(3-4):300-5. doi: 10.1016/j.wneu.2011.12.090. Epub 2011 Dec 28. Reference #2: Dinc N, Won Sy, Eibach M. et al. Cerebral vasospasm due to arteriovenous malformation-associated hemorrhage: Impact of bleeding source and pattern. Cerebrovasc Dis. 2019; 47(3-4):165-170. doi: 10.1159/000500596. Reference #3: Pluta RM, Hansen-Schwartz J, Dreier J, et al. Cerebral vasospasm following subarachnoid hemorrhage: time for a new world of thought. Neurol Res. 2009;31(2):151–158. doi:10.1179/174313209X393564 DISCLOSURES: No relevant relationships by Hammad Arshad, source=Web Response Scientific Medical Advisor relationship with ischemaview Please note: $1-$1000 Added 05/01/2020 by Russell cerejo, source=Web Response, value=Travel No relevant relationships by Nathan Esplin, source=Web Response No relevant relationships by Chen Xu, source=Web Response No relevant relationships by Meilin Young, source=Web Response No relevant relationships by Alexander Yu, source=Web Response

Usefulness of CT angiography for characterizing cerebral arteriovenous malformations presenting as hemorrhage: Comparison with digital subtraction angiography

ObjectiveTo compare the usefulness of CT angiography against the gold standard, digital subtraction angiography (DSA), in the characterisation of cerebral arteriovenous malformations (AVM) that present with bleeding. Material and methodsWe retrospectively analysed patients with intracranial bleeding due to an AVM who were included in a prospective database in the period comprising January 2007 through December 2012. We reviewed radiologic variables such as the characteristics of the AVM (size, location, presence of deep venous drainage), involvement of eloquent areas, and the presence of associated aneurysms. Two neuroradiologists blinded to clinical and radiological information analysed the CT and DSA in consensus. ResultsA total of 22 patients were included in the study. CT angiography correctly classified 15 of the 16 cases of AVM measuring less than 3cm (93.75% sensitivity). All cases of deep venous drainage and all those located in eloquent areas were correctly detected (100% sensitivity). The presence of any type of aneurysm related with the AVM was detected in 13 of 15 cases (86.6% sensitivity); 7 of 9 of the intranidal aneurysms were detected (77.78% sensitivity), as were 6 of the 9 flow aneurysms (66.67% sensitivity). ConclusionCT angiography is highly sensitive in the characterisation of cerebral AVMs measuring less than 3cm, of those located in eloquent areas, and of those with deep venous drainage; it is also highly sensitive in detecting aneurysms related with AVMs. However, CT angiography is less sensitive in detecting intranidal and flow aneurysms related with AVMs.

Utilidad de la angio-TC para la caracterización de malformaciones arteriovenosas cerebrales con presentación hemorrágica comparada con la angiografía por sustracción digital

ObjectiveTo compare the usefulness of CT angiography against the gold standard, digital subtraction angiography (DSA), in the characterization of cerebral arteriovenous malformations (AVM) that present with bleeding. Material and methodsWe retrospectively analyzed patients with intracranial bleeding due to an AVM who were included in a prospective database in the period comprising January 2007 through December 2012. We reviewed radiologic variables such as the characteristics of the AVM (size, location, presence of deep venous drainage), involvement of eloquent areas, and the presence of associated aneurysms. Two neuroradiologists blinded to clinical and radiological information analyzed the CT and DSA in consensus. ResultsA total of 22 patients were included in the study. CT angiography correctly classified 15 of the 16 cases of AVM measuring less than 3cm (93.75% sensitivity). All cases of deep venous drainage and all those located in eloquent areas were correctly detected (100% sensitivity). The presence of any type of aneurysm related with the AVM was detected in 13 of 15 cases (86.6% sensitivity); 7 of 9 of the intranidal aneurysms were detected (77.78% sensitivity), as were 6 of the 9 flow aneurysms (66.67% sensitivity). ConclusionCT angiography is highly sensitive in the characterization of cerebral AVMs measuring less than 3cm, of those located in eloquent areas, and of those with deep venous drainage; it is also highly sensitive in detecting aneurysms related with AVMs. However, CT angiography is less sensitive in detecting intranidal and flow aneurysms related with AVMs.

Combined surgical treatment of the cerebral arteriovenous malformations in patients with the torpid course of the disease

Objective – to optimize the results of surgical treatment of the cerebral arteriovenous malformations (AVM) with a torpid clinical course of the disease.Materials and methods. The results of combined surgical treatment of cerebral AVMs of 36 patients without a history of AVM rupture were analyzed (this variant of clinical course was defined as «torpid»). Patients were treated in the departments of vascular neurosurgery at the Romodanov Neurosurgery Institute NAMS of Ukraine during the period from 2010 till September 2019. Among the patients there were 18 (50 %) men and 18 (50 %) women. The average age of patients was 28.1 years (10–47 years). Clinical, neurological, laboratory, instrumental, functional and morphological methods of examination were used as well as neuroimaging evaluation and follow-up investigation.Results. The «torpid» course of disease in patients with AVM was presented as heterogeneous epileptiform manifestations in 24 (66.7 %) cases. One (2.8 %) patient had seizure that were combined with internal hydrocephalus, 9 (25 %) patients had different severity cephalalgic syndrome (according to the International classification of headache – 3β). Progressive neurological deficit was detected in 2 (5.55 %) patients. The distribution of AVMs according Spetzler–Martin scale (1986) was as follows: grade I – in 2 (5.55 %) patients, grade II – in 10 (27.8 %), grade III – in 13 (36.1 %), grade IV – in 9 (25.0 %), grade V – in 2 (5.55 %). In most cases (94.44 %), AVMs were supratentorial, and in 2 (5.55 %) cases they were subtentorial. The average AVM size in the largest dimension was 3.7 cm (2.8–6.7 cm). Intranidal aneurysms in the AVM structure were diagnosed in 8 (22.2 %) patients, fistulas – in 7 (19.4 %) cases. In all cases, at the first stage, endovascular embolization (EE) of AVM was performed. All 36 patients underwent 64 endovascular procedures. Curative treatment after 1 stage was performed in 16 (44.4 %) patients, after 2 stages – in 13 (36.1%), after 3 stage – in 6 (16.66 %), and after 4 stage in 1 (2.77 %) patient. In 36 (56.25 %) cases, embolization was performed with Onyx composition (eV3), in 24 (37.5 %) – with n-butylcyanoacrylate, and in 3 (4.7 %) – with their combination. In 1 (1.56 %) patient, the fistula was excluded from the blood flow using detached balloon-catheter. Embolization was supplemented with radiosurgical treatment (RST) in 30 (83.3 %) cases, microsurgical removal – in 2 (5.55 %), radiotherapy – in 2 (5.55 %) patients. In 1 (2.77 %) case EE was combined with shunting procedure and RST. One (2.77 %) patient after EE with RST suffered hemorrhagic stroke with intracerebral hematoma formation. An operation was performed for hematoma removal and partially functioning AVM resection. In 7 (10.9 %) cases after EE of AVM, patients developed motor deficits. At the time of discharge, they regressed completely in 6 patients, and partially in 1 patient. In (1.5 %) case homonymous hemianopsia had occurred. After RST, total obliteration of AVM was achieved in 17 (58.6 %) patients, in 5 (17.2 %) – subtotal (repeated RST was recommended). In 7 (24.1 %) cases, positive signs of AVM obliteration was noted, and the timing of radiation exposure did not reach the recommended ones. In 2 (3.1 %) patients after microsurgical resection, the AVM was removed completely, which was confirmed by cerebral angiography. After radiotherapy, decreasing of the AVM size and a positive neurological dynamics were noted. There were no fatal outcomes. According to the modified Rankine scale, patients were distribution to group 0 (33 (91.7 %)) and group I (3 (8.3 %)).Conclusions. The obtained data indicate the promising result of combined surgical treatment of cerebral AVM with a torpid type of clinical manifestations. The leading technique in the applied staged combined surgical treatment of AVM was EE. Its successful use is due to the effectiveness of its impact on all components of the «complex» AVM.