Search

Objective Intra-procedural WEB device migration is a scarcely reported complication that necessitates prompt intervention. Case Presentation Endovascular treatment of two broad necked flow-related aneurysms was planned aided by WEB-SL (Woven EndoBridge-single layer) devices in a 71-year-old female with known left temporal arteriovenous malformation. Inadvertent distal migration occurred while performing a control angiogram with an automated iodine injector. Immediate retrieval was successfully performed using a Solitaire stent-retriever. Conclusion To our knowledge, we report for the first time the successful retrieval of a distally migrated WEB using a stent-retriever device.

Background Cerebello-pontine AVMs (CPAVMs) and petrous apex dural arteriovenous fistulae (DAVFs) are rare and sometimes difficult to distinguish. We report a fatal hemorrhagic complication after coil embolization of the petrosal vein draining a trigeminal AVM misdiagnosed as a DAVF. Case presentation A 73-year-old woman with a petrous apex arteriovenous shunt with dual dural and pial arterial supply presented with posterior fossa hemorrhage. The draining petrosal vein was catheterized and coiled via the superior petrosal sinus. Two episodes of contrast extravasation occurred during coiling, but the lesion was completely occluded at the end of the procedure. The patient developed a fatal posterior fossa hemorrhage in the recovery room. Microscopic pathology revealed numerous dilated vessels within the trigeminal nerve. Conclusion CPAVMs and DAVFs with pial drainage should be distinguished pre-operatively. Occlusion of a pial vein (as opposed to a sinus) in the treatment of an arteriovenous shunt carries hemorrhagic risk if a liquid embolic agent is not used to completely occlude all pathological vessels.

Objective: To assess the utility of intraoperative indocyanine green video angiography (ICG-VA) during microsurgical resection of arteriovenous malformations (AVMs). Methods: Data of the 24 patients, who were surgically treated for AVM using intraoperative ICG-VA, were reviewed retrospectively. Postoperative digital subtraction angiography (DSA) was performed in all patients before they regained consciousness and became fully awake, and the results were compared with those obtained with intraoperative ICG-VA. A scheduled DSA was performed in all patients in the third, sixth, and 12th postoperative months as well. Results: Authors retrospectively analyzed the records of intraoperative ICG-VA application of all 24 patients. Though the exposures were limited and the image qualities were poor at higher magnification on the surgical microscope within deep surgical fields, the AVM niduses, feeding arteries, draining veins, and their relations to normal vasculature were observed precisely with ICG-VA in all the procedures. Furthermore, the visualization was not qualified enough to identify these pathological vascular structures accurately before evacuating and irrigating the layer of blood clots that obscure the view in patients who presented with hemorrhage. In a patient in our series, a residual nidus in the tail of the caudate nucleus was detected with immediate postoperative DSA which was not revealed by terminal assessment with final intraoperative ICG-VA. Conclusions: Intraoperative ICG-VA is particularly effective in the identification of the feeder, nidus, and drainer and in the assessment of the flow dynamics of the nidus in cerebral AVM surgery. It may be a quick and safe technique for intraoperative imaging of the angioarchitecture of superficial AVMs, but it may be less helpful for deep-seated lesions. Furthermore, this method alone may not be useful in the identification of residual disease or improvement of the clinical outcomes. DSA has remained the gold standard for confirming AVM obliteration. Despite the technical limitations associated with ICG-VA, a combination of intraoperative ICG-VA and immediate postoperative DSA may advance the safety and efficacy of AVM surgery. © 2022 Elsevier Inc.

Transradial access is widely used in cardiological adult interventions and less in pediatrics. In recent years, this access has become more popular in the neuroradiological community in adult patients since it has fewer complications and is more comfortable for the patient after the procedure. We present a single-center case series of 52 transradial access neurointerventions (43 angiographies and 9 therapeutic procedures) in pediatric patients, with a failure of 4 cases (7.7%) in which we could not puncture the artery, crossing over to transfemoral access. Since in five cases we did angiography followed by therapeutic intervention, thus doing only one puncture access for both procedures, then our access failure rate was 10.6%. The 34 successful transradial access solely angiographies had a median radiation exposure of 887 mGy (interquartile range 628–1352), median fluoroscopy time of 9.5 min (interquartile range 7.5–15.3), and median procedure time of 28 min (interquartile range 24–33 min) Therapeutic procedure diagnosis were: one ruptured saccular aneurysm, two juvenile nasopharyngeal angiofibromas, and five arteriovenous malformations. The transradial access neurointerventions for pediatric population older than 11 years is safe and feasible, having previous experience in adults. Younger population should be considered on a case-to-case basis, depending on ultrasound measurement of the arterial diameter and the materials available.

Refereed/Peer-reviewed Arteriovenous malformations (AVM) of the brain are congenital, high pressure vascular malformations, which are at risk of haemorrhage. Stereotactic radiosurgery (SRS) can obliterate the nidus by delivering a precise high dose of ionising radiation in a single fraction. This paper updates long term AVM obliteration rates, time to obliteration and retreatment outcomes in LINAC delivered SRS treatment at the Royal Adelaide Hospital. A retrospective review of a prospectively maintained AVM SRS database supplemented by clinical case notes, patient correspondence and electronic medical records was performed. 89 AVMs received primary SRS treatment for which the crude obliteration rate was 61% (68% for 79 patients with adequate follow up). Higher marginal dose, smaller nidus size and lower Pollock-Flickinger (PF) score were significantly associated with AVM obliteration. The crude obliteration rates for patients with adequate follow-up and AVM diameter < 3 cm vs ≥ 3 cm were 76% vs 48%, respectively, and 93% with PF score < 1.0. Median time to obliteration was 36 months. Higher dose and lower PF score were associated with earlier obliteration. The crude obliteration rate after second SRS was 56% (9/16 patients) and no significant associations were found. These obliteration rates after primary and retreatment LINAC SRS are comparable to other studies. Marginal dose and PF score were the main predictors of obliteration overall as well as early (

OBJECTIVE Hereditary hemorrhagic telangiectasia is the only condition associated with multiple inherited brain arteriovenous malformations (AVMs). Therefore, a mouse model was developed with a genetics-based approach that conditionally deleted the causative activin receptor-like kinase 1 (Acvrl1 or Alk1) gene. Radiographic and histopathological findings were correlated, and AVM stability and hemorrhagic behavior over time were examined. METHODS Alk1-floxed mice were crossed with deleter mice to generate offspring in which both copies of the Alk1 gene were deleted by Tagln-Cre to form brain AVMs in the mice. AVMs were characterized using MRI, MRA, and DSA. Brain AVMs were characterized histopathologically with latex dye perfusion, immunofluorescence, and Prussian blue staining. RESULTS Brains of 55 Tagln-Cre+;Alk12f/2f mutant mice were categorized into three groups: no detectable vascular lesions (group 1; 23 of 55, 42%), arteriovenous fistulas (AVFs) with no nidus (group 2; 10 of 55, 18%), and nidal AVMs (group 3; 22 of 55, 40%). Microhemorrhage was observed on MRI or MRA in 11 AVMs (50%). AVMs had the angiographic hallmarks of early nidus opacification, a tangle of arteries and dilated draining veins, and rapid shunting of blood flow. Latex dye perfusion confirmed arteriovenous shunting in all AVMs and AVFs. Microhemorrhages were detected adjacent to AVFs and AVMs, visualized by iron deposition, Prussian blue staining, and macrophage infiltration using CD68 immunostaining. Brain AVMs were stable on serial MRI and MRA in group 3 mice (mean age at initial imaging 2.9 months; mean age at last imaging 9.5 months). CONCLUSIONS Approximately 40% of transgenic mice satisfied the requirements of a stable experimental AVM model by replicating nidal anatomy, arteriovenous hemodynamics, and microhemorrhagic behavior. Transgenic mice with AVFs had a recognizable phenotype of hereditary hemorrhagic telangiectasia but were less suitable for experimental modeling. AVM pathogenesis can be understood as the combination of conditional Alk1 gene deletion during embryogenesis and angiogenesis that is hyperactive in developing and newborn mice, which translates to a congenital origin in most patients but an acquired condition in patients with a confluence of genetic and angiogenic events later in life. This study offers a novel experimental brain AVM model for future studies of AVM pathophysiology, growth, rupture, and therapeutic regression.

Background: A variety of emerging medical imaging technologies based on artificial intelligence have been widely applied in many diseases, but they are still limitedly used in the cerebrovascular field even though the diseases can lead to catastrophic consequences. Objective: This work aims to discuss the current challenges and future directions of artificial intelligence technology in cerebrovascular diseases through reviewing the existing literature related to applications in terms of computer-aided detection, prediction and treatment of cerebrovascular diseases. Methods: Based on artificial intelligence applications in four representative cerebrovascular diseases including intracranial aneurysm, arteriovenous malformation, arteriosclerosis and moyamoya disease, this paper systematically reviews studies published between 2006 and 2021 in five databases: National Center for Biotechnology Information, Elsevier Science Direct, IEEE Xplore Digital Library, Web of Science and Springer Link. And three refinement steps were further conducted after identifying relevant literature from these databases. Results: For the popular research topic, most of the included publications involved computer-aided detection and prediction of aneurysms, while studies about arteriovenous malformation, arteriosclerosis and moyamoya disease showed an upward trend in recent years. Both conventional machine learning and deep learning algorithms were utilized in these publications, but machine learning techniques accounted for a larger proportion. Conclusion: Algorithms related to artificial intelligence, especially deep learning, are promising tools for medical imaging analysis and will enhance the performance of computer-aided detection, prediction and treatment of cerebrovascular diseases.

Both acute and chronic subdural haematomas typically occur following trauma. Non-traumatic causes are less common, but aetiologies include arteriovenous malformation, intracranial aneurysm rupture, tumour-associated haemorrhage and coagulopathies. May-Hegglin anomaly is an example of a coagulopathy, which is caused by a mutation in the gene encoding non-muscle myosin heavy chain 9 (MYH9) and therefore falls into a group of diseases referred to as MYH9-related diseases (MYH9-RD). The symptomology of MYH9-RD is often mild, and patients tend to experience epistaxis, gingival bleeding and bruising. Life-threatening haemorrhage rarely occurs. In this short report, we describe a patient with known May-Hegglin anomaly who presented with a potentially life-threatening, spontaneous subdural haematoma requiring surgery on two occasions. This is only the second such report in the literature, and the first of spontaneous and recurrent haemorrhage in association with May-Hegglin anomaly.

OBJECTIVE Pediatric brain arteriovenous malformations (AVMs) are the leading cause of spontaneous intracranial hemorrhage (SICH) in children. Although the incidence of SICH is low in pediatric populations, such events cause substantial morbidity. The recently created Ruptured Arteriovenous Malformation Grading Scale (RAGS) is proposed as a reliable and novel grading system to specifically serve as a predictor of clinical outcomes in patients following AVM rupture, similar to the Hunt and Hess (HH) grade for ruptured aneurysms. While these data are promising, pediatric patients were notably absent from the original study validating the RAGS. Therefore, correlation of the RAGS score with clinical outcomes following AVM rupture in individuals younger than 18 years of age using the RAGS score is needed. The objective of this study was to validate the RAGS in a cohort of pediatric patients with AVMs who presented with hemorrhage, thereby demonstrating the score’s generalizability, and expanding its external validity. METHODS A cohort of children with ruptured AVMs were retrospectively reviewed. Using disability, measured by the modified Rankin Scale (mRS), as the response variable, the area under the receiver operating characteristic curve (AUROC) was calculated for patients based on their RAGS scores for three time periods. The AUROC values were then compared with those generated by two commonly used clinical grading systems, the HH classification and Glasgow Coma Scale. RESULTS A total of 81 children who presented with ruptured AVMs were included in the study, with a mean follow-up duration of 4 years. The RAGS score outperformed other clinical grading scales in predicting mRS scores, with AUROC values of 0.81, 0.82, and 0.81 at three distinct follow-up periods. CONCLUSIONS The RAGS score correlated well with the clinical outcome after AVM rupture in pediatric patients. Additional validation studies across multiple treatment centers are needed to further demonstrate the generalizability of the scoring system.

Background Cerebellar arteriovenous malformations (cAVMs) are rare and challenging lesions with an aggressive natural history. The mechanisms whereby a patient can worsen clinically after a supratentorial AVM resection include an acute alteration in cerebral hemodynamics, which is a known cause of postoperative hyperemia, edema and/or hemorrhage. These phenomena has not been described for cAVMS. Moreover, the underlying pathophysiology of edema and hemorrhage after AVM resection still remains controversial. Methods We report a patient that presented an abrupt neurological deterioration after cAVM surgical resection. Emergent external ventricular drainage to treat incipient hydrocephalus only partially reverted the patient's deterioration. Consecutive post-surgery CT images revealed fourth ventricle compression secondary to cerebellar swelling that concurred with a new neurological deterioration. Densitometric analysis was performed in these CT images to reveal the nature of these changes as well as their evolution over time. Results Importantly, we demonstrated a dynamic increase in the cerebellum mean density at the interval of Hounsfield values which correspond to hyperemia values. These changes were dynamic, and when hyperemia resolved and cerebellar density returned to basal levels, the fourth ventricle re-expanded and the patient neurologically recovered. Conclusions This study demonstrated the utility of quantitative CT image analysis in the context of hemodynamic alterations following cAVM resection. Densitometric CT analysis demonstrated that hyperemic changes, but not ischemic ones, were time-dependent and were responsible for swelling and hemorrhage that conditioned neurological status and patient's evolution.

Background: Language dysfunction is rarely seen in patients with unruptured brain arteriovenous malformation (AVM) albeit the AVM nidus involving language areas, which provides a unique disease model to study language reorganization. The objective of this study was to investigate the impairment and reorganization patterns and characteristics of language-related white matter in AVMs located at different brain areas. Methods: Thirty-three patients with AVMs involving language areas were prospectively enrolled. Patients were categorized into 3 groups according to the lesion locations: the frontal (14 patients), temporal (15 patients), and parietal groups (4 patients). Thirty age- and sex-matched healthy controls were enrolled as comparison. All participants underwent diffusion tensor imaging scans, and automated fiber quantification method was applied to quantitatively study the difference of segmented language-related white matter connectivity between 3 AVM groups and control group. Results: Language functions were normal in all subjects according to Western Aphasia Battery test. In the frontal group, fractional anisotropy (FA) value decreased in the left arcuate fascicle and increased in left superior longitudinal fasciculus and uncinate fascicle; in the temporal group, FA values decreased in left inferior fronto-occipital fascicle and inferior longitudinal fascicle and increased in right anterior thalamic radiation and uncinate fascicle; in the parietal group, FA values decreased in left arcuate fascicle and inferior longitudinal fascicle and increased in bilateral anterior thalamic radiations and uncinate fascicles and right inferior fronto-occipital fascicle. In fascicles with decreased FA values, the increase of radial diffusivity was common, and fascicles with increased FA values usually presented along with increased axial diffusivity values. Conclusions: Remodeling of language-related white matter occurs when traditional language areas are involved by AVM nidus, and its reorganization patterns vary with locations of AVM nidus. Fascicle impairment is mainly caused by the myelin deficits, and its plasticity may be dominated by the axon remodeling procedure.

OBJECTIVE There have been no accurate surveillance data regarding the incidence rate of spinal arteriovenous shunts (SAVSs). Here, the authors investigate the epidemiology and clinical characteristics of SAVSs. METHODS The authors conducted multicenter hospital-based surveillance as an inventory survey at 8 core hospitals in Okayama Prefecture between April 1, 2009, and March 31, 2019. Consecutive patients who lived in Okayama and were diagnosed with SAVSs on angiographic studies were enrolled. The clinical characteristics and the incidence rates of each form of SAVS and the differences between SAVSs at different spinal levels were analyzed. RESULTS The authors identified a total of 45 patients with SAVSs, including 2 cases of spinal arteriovenous malformation, 5 cases of perimedullary arteriovenous fistula (AVF), 31 cases of spinal dural AVF (SDAVF), and 7 cases of spinal epidural AVF (SEAVF). The crude incidence rate was 0.234 per 100,000 person-years for all SAVSs including those at the craniocervical junction (CCJ) level. The incidence rate of SDAVF and SEAVF combined increased with advancing age in men only. In a comparative analysis between upper and lower spinal SDAVF/SEAVF, hemorrhage occurred in 7/14 cases (50%) at the CCJ/cervical level and in 0/24 cases (0%) at the thoracolumbar level (p = 0.0003). Venous congestion appeared in 1/14 cases (7%) at the CCJ/cervical level and in 23/24 cases (96%) at the thoracolumbar level (p < 0.0001). CONCLUSIONS The authors reported detailed incidence rates of SAVSs in Japan. There were some differences in clinical characteristics of SAVSs in the upper spinal levels and those in the lower spinal levels.

Brain arteriovenous malformation (BAVM) is defined as abnormal communication between cerebral of arteries and veins, without capillaries. Clinically, it may involve intracranial hemorrhage or seizures. Complete spontaneous resolution, known as BAVM disappearance, has been reported in rare cases.We retrospectively collated all cases of BAVM in Lille University Hospital, from 2005 to 2018, and identified all cases of spontaneous BAVM disappearance on angiography (nidus and early venous drainage).There were 4 cases of spontaneous BAVM disappearance, in 3573 patients: i.e., prevalence of 0.1%. Sex ratio was 2:2; ages ranged from 14 to 46 years; nidus size was generally small (20mm); 3 of the 4 patients had superficial venous drainage. Revelation of BAVM was by hemorrhage in 3 cases and by seizure in 1. There were no cases of recanalization at 1 year's follow-up.Spontaneous BAVM disappearance is rare. Associated factors may include small nidus, superficial venous drainage and hemorrhage.

OBJECTIVE The optimal treatment paradigm for large arteriovenous malformations (AVMs) is controversial. One approach is volume-staged stereotactic radiosurgery (VS-SRS). The authors previously reported efficacy of VS-SRS for large AVMs in a multiinstitutional cohort; here they focus on risk of symptomatic adverse radiation effects (AREs). METHODS This is a multicentered retrospective review of patients treated with a planned prospective volume staging approach to stereotactically treat the entire nidus of an AVM, with volume stages separated by intervals of 3–6 months. A total of 9 radiosurgical centers treated 257 patients with VS-SRS between 1991 and 2016. The authors evaluated permanent, transient, and total ARE events that were symptomatic. RESULTS Patients received 2–4 total volume stages. The median age was 33 years at the time of the first SRS volume stage, and the median follow-up was 5.7 years after VS-SRS. The median total AVM nidus volume was 23.25 cm3 (range 7.7–94.4 cm3), with a median margin dose per stage of 17 Gy (range 12–20 Gy). A total of 64 patients (25%) experienced an ARE, of which 19 were permanent. Rather than volume, maximal linear dimension in the Z (craniocaudal) dimension was associated with toxicity; a threshold length of 3.28 cm was associated with an ARE, with a 72.5% sensitivity and a 58.3% specificity. In addition, parietal lobe involvement for superficial lesions and temporal lobe involvement for deep lesions were associated with an ARE. CONCLUSIONS Size remains the dominant predictor of toxicity following SRS, but overall rates of AREs were lower than anticipated based on baseline features, suggesting that dose and size were relatively dissociated through volume staging. Further techniques need to be assessed to optimize outcomes.

We report a case of gamma knife surgery (GKS)-induced chronic encapsulated expanding hematoma with extensive literature review. A 17-year-old young man underwent GKS after embolization for arteriovenous malformation (AVM) in the right frontal lobe and the AVM completely disappeared. He developed a generalized convulsion 15 years after GKS. MRI showed a small oedematous change at the AVM site. His epileptic seizure was controlled with anticonvulsant. His epilepsy recurred after three years, and MRI revealed an intracerebral hematoma with extensive surrounding edema at the same lesion. He underwent cerebral angiography and a recurrence of AVM was prevented. The hematoma was surgically removed, and intraoperative finding confirmed an old hematoma with a capsule and capillary hyperplasia, without developing cavernous angioma. The final diagnosis was a secondary chronic encapsulated expanding hematoma after GKS. This is the first report to show the early-stage imaging findings of this late effect after GKS.

To evaluate the utility of integrating a 3D vessel tree co-registration software platform into the stereotactic radiosurgery (SRS) workflow and its time saving for brain arteriovenous malformation (bAVM) treatment in adults compared to the conventional stereotactic head frame workflow. Eight consecutive adult bAVM cases were selected and retrospectively reviewed. Total number of angiograms and SRS procedures were 8. The electronic medical records were analyzed by time stamps to determine the length of time for each component of the set-up, transport, and frame removal. Times were averaged and the start of sedation by anesthesia used as a surrogate for the start of the frame application process. Reductions in workflow times were then modeled assuming cerebral angiography as a separate procedure. There were 8 adult bAVM cases included. Six were female. All patients had a single treatment session. Average age was 51.5 years (Range: 36-71). All patients were treated under monitored anesthesia care. In 6 patients, the AVM was deeply located (basal ganglia, midbrain, brainstem); in 2 cases, the lesion was frontal. Spetzler-Martin grades were 4 (50%) Grade 2 and 4 (50%) Grade 3. The average prescription isodose volume (PIV) and 12 Gy volumes (V12Gy) were 0.85 cc and 1.74 cc, respectively. The mean time from frame application to arrival in the angiography room was 111.5 minutes (range 40 to 171 min; median 107 min; SD 35.3 min); transport from angiography room to SRS was 47.5 minutes (range 15 to 107 min; median 36 min; SD 31.1 min), and frame removal after SRS was 20.5 minutes (range 10 to 47 min; median 16 min; SD 11.6 min). The average total additional time for the entire process of frame application, patient transportation, and frame removal was 132 minutes (range 87 to 181 min; median 127.5 min; SD 28.4 min). Therefore, assuming a non-frame based workflow and with angiography performed ahead of the actual radiosurgical treatment, the total time savings on the day of treatment was estimated at 132 minutes (range 87 to 181 min; median 127.5 min; SD 28.4 min). The ability to perform angiography, image fusion, and treatment planning for the actual day-of-delivery using 3-dimensional vessel tree co-registration could result in significant time savings over traditional workflow practices. Further experience with this system will evaluate its accuracy, reproducibility, and potential broader use in SRS workflow paradigms for the treatment of vascular pathologies. For bAVMs, the benefits of this time savings might allow for streamlined workflows on the day of SRS.

OBJECTIVE Microsurgical resection of arteriovenous malformations (AVMs) can be aided by staged treatment consisting of stereotactic radiosurgery followed by resection in a delayed fashion. This approach is particularly useful for high Spetzler-Martin (SM) grade lesions because radiosurgery can reduce flow through the AVM, downgrade the SM rating, and induce histopathological changes that additively render the AVM more manageable for resection. The authors present their 28-year experience in managing AVMs with adjunctive radiosurgery followed by resection. METHODS The authors retrospectively reviewed records of patients treated for cerebral AVMs at their institution between January 1990 and August 2019. All patients who underwent stereotactic radiosurgery (with or without embolization), followed by resection, were included in the study. Of 1245 patients, 95 met the eligibility criteria. Univariate and multivariate regression analyses were performed to assess relationships between key variables and clinical outcomes. RESULTS The majority of lesions treated (53.9%) were high grade (SM grade IV–V), 31.5% were intermediate (SM grade III), and 16.6% were low grade (SM grade I–II). Hemorrhage was the initial presenting sign in half of all patients (49.5%). Complete resection was achieved among 84% of patients, whereas 16% had partial resection, the majority of whom received additional radiosurgery. Modified Rankin Scale (mRS) scores of 0–2 were achieved in 79.8% of patients, and 20.2% had poor (mRS scores 3–6) outcomes. Improved (44.8%) or stable (19%) mRS scores were observed among 63.8% of patients, whereas 36.2% had a decline in mRS scores. This includes 22 patients (23.4%) with AVM hemorrhage and 6 deaths (6.7%) outside the perioperative period but prior to AVM obliteration. CONCLUSIONS Stereotactic radiosurgery is a useful adjunct in the presurgical management of cerebral AVMs. Multimodal therapy allowed for high rates of AVM obliteration and acceptable morbidity rates, despite the predominance of high-grade lesions in this series of patients.

Arteriovenous malformation (AVM) combined with aneurysms is not uncommon, but AVM of the basilar artery, brainstem, and right middle cerebral artery combined with multiple intracranial aneurysms (IAs) is rare. Cases of aneurysm protrusion into the optic canal are also rare. We report a distinctive case of intracranial AVM combined with multiple IAs and partial protrusion of a cavernous segment aneurysm of the right internal carotid artery into the optic nerve canal.Teaching Point: Cases of partial protrusion of a cavernous segment aneurysm of the right internal carotid artery into the optic canal, resulting in widening of the optic canal compared to the contralateral side, compression, thickening and swelling of the subocular veins, and obstruction of venous drainage warrant the clinician’s attention.

Arteriovenous malformations (AVMs) are congenital high flow pathologic linkages between arteries and veins of different sizes that may occur in any part of the body. The clinical presentation is largely dependent on the size and location of AVMs and can range from an asymptomatic birthmark to congestive heart failure in extreme cases. In this report, we describe a 20-year-old male who presented with a large AVM of the right shoulder that resulted in significant cosmetic and physical impairment and treated with several sessions of endovascular embolization with good clinical outcomes. This case highlights the complexity of diagnosing and managing these AVMs. Most of these anomalies require a multi-disciplinary approach that integrates both trans-catheter and surgical interventions with trans-arterial lesion embolization being the cornerstone of the treatment.

OBJECTIVE The aim of this study was to 1) compare the safety and efficacy of acute targeted embolization of angiographic weak points in ruptured brain arteriovenous malformations (bAVMs) versus delayed treatment, and 2) explore the angioarchitectural changes that follow this intervention. METHODS The authors conducted a retrospective analysis of a prospectively acquired database of ruptured bAVMs. Three hundred sixteen patients with ruptured bAVMs who presented to the hospital within 48 hours of ictus were included in the analysis. The first analysis compared clinical and functional outcomes of acutely embolized patients to those with delayed management paradigms. The second analysis compared these outcomes of patients with acute embolization to those with angiographic targets who did not undergo acute embolization. Finally, a subset of 20 patients with immediate postembolization angiograms and follow-up angiograms within 6 weeks of treatment were studied to determine the angioarchitectural changes after acute targeted embolization. Kaplan-Meier curves for survival between the groups were devised. Multivariate logistical regression analysis was conducted. RESULTS There were three deaths (0.9%) and an overall rerupture rate of 4.8% per year. There was no statistical difference in demographic variables, mortality, and rerupture rate between patients with acute embolization and those with delayed management. Patients with acute embolization were more likely to present functionally worse (46.9% vs 69.8%, modified Rankin Scale score 0–2, p = 0.018) and to require an adjuvant therapy (71.9% vs 26.4%, p < 0.001). When comparing acutely embolized patients to those nonacutely embolized angiographic targets, there was a significant protective effect of acute targeted therapy on rerupture rate (annual risk 1.2% vs 4.3%, p = 0.025) and no difference in treatment complications. Differences in the survival curves for rerupture were statistically significant. Multivariate analyses significantly predicted lower rerupture in acute targeted treatment and higher rerupture in those with associated aneurysms, deep venous anatomy, and higher Spetzler-Martin grade. All patients with acute embolization experienced complete obliteration of the angiographic weak point with various degrees of resolution of the nidus; however, some had spontaneous recurrence of their bAVM, while others had spontaneous resolution over time. No patients developed new angiographic weak points. CONCLUSIONS This study demonstrates that acute targeted embolization of angiographic weak points, particularly aneurysms, is technically safe and protective in the early phase of recovery from ruptured bAVMs. Serial follow-up imaging is necessary to monitor the evolution of the nidus after targeted and definitive treatments. Larger prospective studies are needed to validate these findings.

Cobb Syndrome (Spinal Arteriovenous Metameric Syndrome 1-31 (SAMS 1-31)) is a rare, non-hereditary disorder. Approximately 100 cases of CS have been described to date. The actual incidence may be much higher since only symptomatic patients were documented. In particular, post mortem studies suggest a possibly higher incidence of this syndrome. The main clinical manifestations of this syndrome include skin stains of vascular nature on the torso, in combination with spinal vascular malformations localized in one and the same metameric or spinal segment. A rare diagnosis of this syndrome in patients over 18 is probably related to the fact that the disease may be asymptomatic throughout a long period of time, while patients may tend to disregard the skin lesions. As a result, most publications on this pathology are based on separate case reports. : Significant variability of clinical manifestations as well as prolonged progress of the disease often cause errors in diagnosis. What follows is a case report of a young patient with Cobb Syndrome, who was admitted to a regional vascular centre with a misdiagnosis of stroke. : 20 patients of young age (from 20 to 35 years old), with a diagnosis of stroke, who were admitted to a University Clinic (of the Russian National Research Medical University Named After Pirogov N.I., Moscow). Among this group of patients, a patient with Cobb syndrome was identified. Patient P., of 22 years, presented with acute, intensive cervical spinal pain, predominantly on the right, numbness and weakness in the arms and legs. About 3 weeks before admission to the hospital, the patient had ARVI with a fever of up to 37.5°C: two weeks before the onset of symptoms, he had undergone extirpation of 2 teeth, for which reason he spent over 2 hours in a forced position with his head thrown back (prolonged overextension in the cervical spine). Multiple skin angiomas on the chest spreading to the shoulder and scapula region. Tetraparesis up to 4 points: tetraparesis in hands with low muscle tone, low reflexes, tetraparesis in legs with high muscle tone, high reflexes, foot clonus when causing Achilles reflexes, tremor in the extremities and no plantar reflex pathology were detected, sensitivity disorders in the hands “the high gloves” and no pelvic disorders were detected. Given the presence and exacerbation of neurological symptoms and cutaneous angiomas, MRI with a contrast agent of the cervical spine was recommended. MR-image of an advanced arteriovenous malformation (AVM) of the cervical spinal cord with signs of gliosis and spinal cord oedema at the C2-C7 level. Endovascular embolization of the AVM in the cervical spinal cord was performed. The treatment led to the complete reversal of neurological symptoms. In the presence of skin lesions, the diagnosis of CS does not present particular difficulties, so in children and young patients with skin angiomatosis, it is advisable to conduct a comprehensive examination using selective spinal angiography or MR angiography to exclude arteriovenous malformations in the spinal cord.

Objective To analyze a case of heavy uterine bleeding in adolescence caused by an arteriovenous malformation (AVM) in Hanoi Obstetrics and Gynecology Hospital, Vietnam. Methods We observed a case of a 14-year-old girl, without vaginal sexual intercourse experience, having heavy uterine bleeding caused by AVM. She underwent a laparoscopic operation at the hospital for vascular lesions in the uterine anterior wall, which caused an internal hemorrhage of 1500 ml blood loss into the peritoneal cavity. Three years later, this patient was hospitalized twice for massive vaginal bleeding. Results Results of ultrasound and magnetic resonance imaging indicated a uterine intramural mass with enlarged vessels connecting to the endometrial cavity. A pelvic digital subtraction angiography was performed and showed profuse bleeding from a ruptured branch of the left uterine artery. This artery was embolized at Bach Mai hospital and the bleeding was stopped. The patient had stable health and normal menstrual periods after 4 months of follow up. Conclusion Abnormal mass with dilated vessels in the myometrium in a patient experiencing heavy uterine bleeding is an exclusive sign of uterine vascular malformation and can be treated by angioembolization.

Objective : The aim of this study to investigate the benefits of patient-based 3-dimensional (3D) cerebral arteriovenous malformation (AVM) models for preoperative surgical planning and education.Methods : Fifteen patients were operated on for AVMs between 2015 and 2019 with patient-based 3D models. Ten patients’ preoperative cranial angiogram screenings were evaluated preoperatively or perioperatively via patient-based 3D models. Two patients needed emergent surgical intervention; their models were solely designed based on their AVMs and used during the operation. However, the other patients who underwent elective surgery had the modeling starting from the skull base. These models were used both preoperatively and perioperatively. The benefits of patients arising from treatment with these models were evaluated via patient files and radiological data.Results : Fifteen patients (10 males and five females) between 16 and 66 years underwent surgery. The mean age of the patients was 40.0±14.72. The most frequent symptom patients observed were headaches. Four patients had intracranial bleeding; the symptom of admission was a loss of consciousness. Two patients (13.3%) belonged to Spetzler-Martin (SM) grade I, four (26.7%) belonged to SM grade II, eight (53.3%) belonged to SM grade III, and one (6.7%) belonged to SM grade IV. The mean operation duration was 3.44±0.47 hours. Three patients (20%) developed transient neurologic deficits postoperatively, whereas three other patients died (20%).Conclusion : Several technological innovations have emerged in recent years to reduce undesired outcomes and support the surgical team. For example, 3D models have been employed in various surgical procedures in the last decade. The routine usage of patient-based 3D models will not only support better surgical planning and practice, but it will also be useful in educating assistants and explaining the situation to the patient as well.

Cerebrovascular disease is a broad topic. This document focuses on the imaging recommendations for the varied clinical scenarios involving intracranial aneurysms, vascular malformations, and vasculitis, which all carry high risk of morbidity and mortality. Additional imaging recommendations regarding complications of these conditions, including subarachnoid hemorrhage and vasospasm, are also covered. While each variant presentation has unique imaging recommendations, the major focus of this document is neurovascular imaging techniques. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Arteriovenous malformation of the uterus (AVMU) is a very rare and uncommon condition, because it has been documented that less than 100 cases of AVMU have been reported in the literature. AVMU is potentially a life-threatening condition with regard to the fact that some cases of AVMU could manifest with profuse bleeding from the uterus via the vagina. AVMU could either be congenital AVMU which is less common or acquired AVMU with pregnancy noted to have a role to play in the pathogenesis of AVMUs. The true incidence of AVMU is stated to be difficult to ascertain in view of the fact that some cases of bleeding that have been caused by AVMU do tend to conservative, medical management and many of these AVMUs could remain undiagnosed. The most common manifestations of AVMUs tend to be abnormal uterine bleeding that could be episodic, intermittent, continuous, mild or torrential which could lead to severe anaemia or shock. Some AVMUs could be found incidentally based upon radiology imaging for a different condition. Other symptoms of AVMUs do include: Metrorrhagia; Menorrhagia; Bleeding following a miscarriage; Bleeding following dilatation and curettage; Bleeding subsequently after hysterectomy; Bleeding associated with trophoblastic disease; Bleeding following caesarean section; Post-partum haemorrhage; Intermittent vaginal bleeding; Continuous vaginal bleeding; Post-menopausal bleeding; Acute abdominal pain with hemoperitoneum; Pallor; Dizziness; Weakness; Drowsiness; Being unwell following delivery of a baby; Bleeding following therapeutic abortion; Tachycardia; Supra-pubic pain at times; hypotension. Diagnosis of AVMU tends to be made based upon radiology imaging with utilization of ultrasound scan / Doppler scan of the uterus and pelvis, Contrast Computed Tomography scan, and Contrast Magnetic Resonance Imaging Scan, as well as by selective angiography which tends to be ensued by treatment with embolization of the feeding vessels to the AVMU. The treatment of AVMUs these days has ranged between conservative and medical management that includes hormones for small AVMUs, Hysterectomy, which tends to be a definitive treatment that removes the AVMU but does leave the individual not being able to maintain her future fertility, as well as selective angiography and super-selective embolization of the uterine arterial branches feeding the AVMU, which does tend to maintain the future fertility of the patients and which has the advantage of being undertaken under local anaesthesia. Questions that should be on the minds of clinicians include should doppler ultrasound scan of the uterus be undertaken with regard to all women who develop persistent vaginal bleeding pursuant to or during management of miscarriage, considering that there are very few interventional radiologists in many hospitals. This means that selective angiography plus super-selective embolization cannot be undertaken in district hospitals should all women who have suspected AVMU that have severe bleeding that may require surgical operation be referred to a tertiary hospital so that they could possibly benefit from the undertaking of selective angiography and embolization of their AVMUs instead of hysterectomy to enable them to maintain their future fertility? It is also important for clinicians to be made aware of the existence of AVMUs so that they could appreciate the risk factors as well as the clinical manifestations who should be suspected of possibly having AVMUs. Clinicians also need to learn about various conservative and expectant methods of treating AVMUs including hormonal treatment. Clinicians also need to appreciate the future implications for future fertility of women who have AVMUs. Possible treatment options that have not been utilized for the treatment of AVMUs include: (a) Radiology image-guided cryotherapy of AVMU, (b) Radiology image-guided radiofrequency ablation of AVMU, and (c) Radiology Image-guided Irreversible electroporation of AVMU. There is a global need for the training of more interventional radiologists all over the world including in the developing countries as well as some of the developed countries to that they can undertake embolization of AVMUs as well as they can provide various interventional radiology treatment options for various other conditions.

Rationale: Brain arteriovenous malformations (bAVMs) are abnormal entanglement of blood vessels in brain, with direct connections from arteries to veins, lacking functional capillary bed. Although several somatic mutations were reported, the molecular mechanism and genetic disposition of bAVM remain poorly understood. Objective: We aim to identify transcriptional anomalies and critical functional pathways in bAVM lesions and explore their association with key de novo germline and somatic variants in bAVM patients. Methods and Results: We established a comprehensive bAVM dataset from 269 patients, by performing single-cell sequencing of 17 bAVM lesions, whole-exome sequencing of germline DNA from 60 case-unaffected-parental trios, and genomic/transcriptomic sequencing of 231 bAVM lesions. We found abnormal expression of endothelial and mesenchymal markers in bAVM at both bulk and single-cell level, which was validated by flow cytometric analysis and immunofluorescence staining, suggesting an involvement of endothelial-to-mesenchymal transition (EndMT) process in AVM (arteriovenous-malformation). Using data from the 60 trios, we identified nonsynonymous de novo germline mutations affecting 46 genes, including EXPH5 (detected in 2 independent cases), and vessel-related genes, such as EPAS1 and ENG . Interestingly, knockdown of epas1 in zebrafish embryo showed AVM-like phenotype exclusively in brain. Subsequent computational and experimental analyses demonstrated that expression of genes affected by de novo germline mutations was enriched in vascular cell types and was involved in EndMT-relevant behaviors including cell migration, angiogenesis, and cell marker transition. Moreover, we detected somatic KRAS mutations in 129 of 179 (72%) cases and showed that KRAS mutations were associated with bleeding as the first symptom ( P =0.0072). Following experimental studies demonstrated that KRAS mutations independently regulated EndMT features, consolidating the involvement of EndMT in this disease. Lastly, we showed that lovastatin reversed EndMT features in vitro and ex vivo. Conclusions: Our results suggest the convergent role of de novo germline mutations and somatic mutations in regulating EndMT in bAVM and provided a potential therapeutic option.

Arteriovenous malformations in the mediastinum are rare and extremely unusual in middle mediastinum. The present report describes a 26-year male with spontaneous massive hemoptysis due to arteriovenous malformation in middle mediastinum and successful management by endovascular embolization. Spontaneous massive hemoptysis can be a presenting feature of arteriovenous malformation in middle mediastinum and endovascular embolization can be curative.

Objective To quantify the efficacy of medical management of uterine arteriovenous malformation (AVM) and compare efficacy between different classes of medication. In addition, we evaluated for factors associated with treatment success and pregnancy outcomes after medical management. Design Systematic review and meta-analysis. Setting Not applicable. Patient(s) Thirty-two studies representing 121 premenopausal women with medically-treated uterine AVM were identified via database searches of MEDLINE, Embase, Web of Science, and cited references. Intervention(s) Medical treatment with progestins, gonadotropin-releasing hormone agonists (GnRH-a), methotrexate, combined hormonal contraception , uterotonics, danazol, or combination of the above. Main Outcome Measure(s) Primary outcome of treatment success was defined as AVM resolution without subsequent procedural interventions. Secondary outcome was treatment complication (readmission or transfusion). Result(s) The overall success rate of medical management was 88% (106/121). After adjusting for clustering effects, success rates for progestin (82.5%; 95% confidence interval [CI], 70.1%–90.4%), GnRH-a (89.3%; 99% CI, 71.4%–96.5%) and methotrexate (90.0%; 99% CI, 55.8%–98.8%) were significantly different from the null hypothesis of 50% success. The agents with the lowest adjusted proportion of complications were progestins (10.0%; 99% CI, 3.3%–26.8%) and GnRH-a (10.7%; 99% CI, 3.5%–28.4%). No clinical factors were found to predict treatment success. Twenty-six subsequent pregnancies are described, with no reported recurrences of AVM. Conclusion(s) Medical management for uterine AVM is a reasonable approach in a well selected patient. These data should be interpreted in the context of significant publication bias.

Background Cerebral arteriovenous malformation (AVM) can rarely occur in conjunction with moyamoya disease (MMD). There is still no consensus on how to treat AVM when accompanied by MMD. In this study, we assessed the clinical features and suggested appropriate management when AVM was combined with MMD. Methods From August 1994 to December 2020, 7 out of 4004 patients with MMD were found to have AVM. The Karnofsky Performance Scale (KPS) was used to evaluate the clinical outcomes of AVM and MMD. KPS greater than 80 was classified as a good outcome. In addition, the radiologic outcomes of the patients were evaluated. Results The incidence of AVM with MMD was 1.7 per 1000 persons. Five patients underwent bypass surgery for MMD, and 5 patients underwent Gamma Knife surgery (GKS) for concurrent AVM. Postoperative perfusion magnetic resonance imaging and brain single photon emission computerized tomography showed improved cerebral hemodynamics in 4 out of 7 territories. Postoperative cerebral angiography showed good revascularization in 4 out of 8 territories. After GKS, 4 patients showed complete obliteration, and 1 patient showed a significantly decreased AVM size. Six patients showed favorable clinical outcomes (KPS 80–100), and 1 patient with delayed GKS for AVM had a poor outcome (KPS 20) due to AVM rupture. Conclusions In this study, AVM tended to occur where the angiographic stage of MMD was higher. When AVM is combined with MMD, MMD bypass surgery is recommended based on symptoms and cerebral perfusion status. For AVM, less invasive but effective treatments, such as GKS, should be implemented as soon as possible.

Intracranial mixed vascular malformations (MVMs) are defined as any combination of a developmental venous anomaly (DVA), cerebral cavernous malformation (CCM), capillary telangiectasia (CTG), or arteriovenous malformation (AVM) within a single, contiguous lesion. However, most MVMs described in the literature contain only 2 pathologically discrete malformations; juxtaposition of 3 or more abnormalities in a single lesion remains exceedingly rare. We present the case of a 19-month-old female with new onset focal seizures and a 4-cm right basal ganglia lesion initially believed to be an embryonal neoplasm. She subsequently underwent gross total resection (GTR) of the lesion via a transsylvian-transinsular approach. Intraoperatively, the lesion appeared to be heterogenous and highly vascular, with areas of purplish-gray friable tissue. Pathology confirmed the lesion to be a MVM containing a CCM, CTG, and a DVA. This appears to be the first reported case of such a lesion confirmed on pathology in the literature.

The presence of airway and lung disease in children with congenital heart disease is commonly observed with both cardiac CT angiography and routine chest CT. In this review we discuss abnormalities encountered on CT imaging of the chest beyond the heart and central vasculature, focusing on the airways, lung parenchyma and peripheral vasculature. Preoperative and postoperative findings are reviewed as well.

We are describing a case of a 14-year-old girl who developed acute cerebral infarction which was documented on diffusion-weighted magnetic resonance imaging (DWI). On detailed evaluation, diagnosis of cerebral proliferative angiopathy (CPA) was made. Incidentally, she had capillary malformation on the forehead contralateral to cerebral vascular malformation. To our knowledge, this is the first case of CPA in the literature where DWI abnormality was due to acute cerebral infarction.

Uterine vascular abnormalities though are not very common but are potentially life threatening as can lead to torrential vaginal bleeding. Although they are considered relatively rare, with fewer than 150 cases reported in the literature, a true incidence of the uterine AVM may be much higher. We are reporting a case which was diagnosed as molar pregnancy and suction curettage was done, at the time of the evacuation there was excessive bleeding which was immediately dealt with the tamponade by the Foleys catheter and the vaginal packs till the arrangements for the uterine artery embolization were done. At the time of embolization right uterine artery arteriovenous malformation was detected incidentally and embolized along with the uterine arteries. The post op recovery of the patient was uneventful. Retrospectively when the Doppler ultrasound was reassessed hypoechoic lesions and dilated veins were seen in the myometrium which were misdiagnosed as molar. In any patient if the myometrium shows dilated veins and on Doppler if abnormal active vessel flow with a coloured mosaic pattern is detected uterine AVM should be suspected and should be investigated further with the computed tomography (CT) for proper treatment of the patient and prevention of the life-threatening haemorrhage. Key words: Uterine artery embolization, haemorrhage, dilatation and curettage. Uterine AVM.

Background Pulmonary arterial venous malformation (PAVM) is an abnormal vascular malformation between pulmonary arteries and veins characterized by varying degrees of right-to-left shunts (RLS). Cryptogenic stroke (CS) due to paradoxical embolism (PE) caused by PAVM is relatively rare in the clinic. Case Presentation We report the case of a 54-year-old right-handed woman who presented with sudden-onset left-sided limb weakness for 2 h. A physical examination revealed normal vital signs but weakness in her left upper and lower limbs, graded as 1/5 using the Medical Research Council scale. Her National Institutes of Health Stroke Scale (NIHSS) score was 8, and her modified Rankin scale (mRS) was 4. Brain diffusion-weighted imaging showed acute infarction in the right basal ganglia and the radiation crown but brain magnetic resonance angiography found no obvious abnormality. A transcranial Doppler ultrasound with bubble study (TCD-b) found the rain curtain sign of microbubbles in the left middle cerebral artery, reflecting significant RLS. Transesophageal echocardiography (TEE) and transthoracic echocardiography (TTE) were conducted to distinguish between intra- and extracardiac shunts. A pulmonary computerized tomography angiogram (CTA) demonstrated a PAVM. We considered the patient had CS due to PE caused by PAVM. Thrombolytic therapy within the time window was performed. Then, transcatheter device occlusion of the arteriovenous fistula was successfully undertaken, and the patient carried on with rehabilitation training. At a 15-month follow-up, there were no catheter-related complications or recurrent stroke, and her NIHSS and mRS scores were both 0. Conclusions PAVM is an important risk factor for PE and CS and should not be ignored as a possible etiology in stroke patients without any other risk factors. CTA of the pulmonary artery is the recommended gold standard for diagnosing and locating a PAVM. Thrombolytic therapy within the time window combined with transcatheter device occlusion of arteriovenous malformation and rehabilitation training may benefit the recovery of patients with CS caused by PE resulting from PAVM. Supplementary Information The online version contains supplementary material available at 10.1007/s40120-021-00275-y.

Sciatic nerve symptomatology may arise from both intra- and extra-neural pathology, at any point along descent from the sacral plexus to its bifurcation. The potential aetiology is broad, ranging from degenerative spinal disease to muscle, bony and vascular pathology. We present an extremely unusual case of position and exercise-induced nerve compression secondary to arteriovenous malformation and review the potential extraspinal causes, many of which may be ameliorated by surgical excision or decompression. We further discuss the usefulness of diagnostic imaging, specific clinical tests and histopathological tools that may aid in management.

OBJECTIVE Investigations of the combined effects of neoadjuvant Onyx embolization and stereotactic radiosurgery (SRS) on brain arteriovenous malformations (AVMs) have not accounted for initial angioarchitectural features prior to neuroendovascular intervention. The aim of this retrospective, multicenter matched cohort study is to compare the outcomes of SRS with versus without upfront Onyx embolization for AVMs using de novo characteristics of the preembolized nidus. METHODS The International Radiosurgery Research Foundation AVM databases from 1987 to 2018 were retrospectively reviewed. Patients were categorized based on AVM treatment approach into Onyx embolization (OE) and SRS (OE+SRS) or SRS alone (SRS-only) cohorts and then propensity score matched in a 1:1 ratio. The primary outcome was AVM obliteration. Secondary outcomes were post-SRS hemorrhage, all-cause mortality, radiological and symptomatic radiation-induced changes (RICs), and cyst formation. Comparisons were analyzed using crude rates and cumulative probabilities adjusted for competing risk of death. RESULTS The matched OE+SRS and SRS-only cohorts each comprised 53 patients. Crude rates (37.7% vs 47.2% for the OE+SRS vs SRS-only cohorts, respectively; OR 0.679, p = 0.327) and cumulative probabilities at 3, 4, 5, and 6 years (33.7%, 44.1%, 57.5%, and 65.7% for the OE+SRS cohort vs 34.8%, 45.5%, 59.0%, and 67.1% for the SRS-only cohort, respectively; subhazard ratio 0.961, p = 0.896) of AVM obliteration were similar between the matched cohorts. The secondary outcomes of the matched cohorts were also similar. Asymptomatic and symptomatic embolization-related complication rates in the matched OE+SRS cohort were 18.9% and 9.4%, respectively. CONCLUSIONS Pre-SRS AVM embolization with Onyx does not appear to negatively influence outcomes after SRS. These analyses, based on de novo nidal characteristics, thereby refute previous studies that found detrimental effects of Onyx embolization on SRS-induced AVM obliteration. However, given the risks incurred by nidal embolization using Onyx, this neoadjuvant intervention should be used judiciously in multimodal treatment strategies involving SRS for appropriately selected large-volume or angioarchitecturally high-risk AVMs.

Arteriovenous malformation (AVM) is a congenital pathology of the development of brain vessels in which the arterial and venous blood beds are directly connected by tangled degenerate vessels. This dangerous disease affects the brain functioning and increasing the risk of intracranial hemorrhage. A method of treating the AVM is embolization, which is the surgery of endovascular filling of AVM vessels by a special embolic agent to block blood flow through them. This method is widely used; however, it sometimes is accompanied by intraoperative rupture of AVM vessels. A combined model of the embolization process is proposed that, in addition to the flow of blood and embolic agent in the AVM, takes into account the overflow of blood into surrounding healthy vessels. For modeling the joint flow of blood and embolic composition within the AVM, a one-dimensional model of two-phase filtering is used. This model is built on the basis of clinical data of real patients obtained during neurosurgeries in the Meshalkin National Medical Research Center. Mathematically, this leads to a special initial boundary value problem for an integro-differential equation with a nonconvex flow. For numerical computations, a monotone modification of the CABARET scheme is constructed that highly accurately localizes the strong and weak discontinuities in the solution to the problem. The main purpose of this paper is to find the optimal scenario of the AVM embolization with respect to safety and efficiency. The objective functional and the constraints occurring in the resulting optimal control problem are chosen according to medical grounds. In the future, it is planned to use the optimal solutions obtained in this paper to improve the surgery technique and increase the safety of neurosurgical operations.

Background: Arteriovenous Malformations (AVMs) are abnormalities in intracranial vessels between the arterial and venous systems. This study aimed to identify the predictors of mortality in patients that presented to our hospital with AVMs, ruptured or unruptured, and correlate them to those available in the literature. Methods: An analytical, observational, retrospective study was performed to review data of patients with cerebral AVMs in the University Hospital “Dr José Eleuterio González” from January 2016 to December 2020. Clinical files were reviewed based on AVMs diagnosis according to the International Classification of Diseases 10th Revision, ICD-10. Variables were subjected to a univariate analysis and those found significant (p-value < 0.05) were subjected to a logistic regression. Results: A total of 80 patients were included in our study. Most of the participants were females (56.3%) and three were pregnant. The most common presenting symptom was holocranial headache (34 cases) occurring between the hours of 22:00 to 7:00. The most significant predictors of mortality were a total bleeding volume greater than 9.18 cm3 (p = 0.010), the presence of more than one symptom (p = 0.041), and a history of previous cerebral intraparenchymal hemorrhage (p = 0.014). Conclusion: Results demonstrated an important association between intracranial bleeding and mortality. Ultimately, more prospective studies are needed to determine predictor factors for mortality in AVMs patients.

Vein of Galen malformations (VOGMs) represent a rare pathologic entity with often catastrophic natural history. The advances in endovascular treatment in recent years have allowed for a paradigm shift in the treatment and outcome of these high-flow shunts, even though their pathogenetic mechanisms and evolution remain in part obscure.The overall management of VOGMs requires a tailored case-to-case approach, starting with in utero detection and reserving endovascular treatment for indicated cases. Lately, the advances in translational research with whole-genome sequencing and the coupling with cellular-level hemodynamics attempt to shed more light in the pathogenesis and evolution of these lesions. At the same time the advances in endovascular techniques allow for more safety and tailored technical strategy planning. Furthermore, the advances in MRI techniques allow a better understanding of their vascular anatomy. In view of these recent advances and by performing a PUBMED literature review of the last 15 years, we attempt a review of the evolutions in the imaging, management, endovascular treatment and understanding of underlying mechanisms for VOGMs.The progress in the fields detailed in this review appears very promising in better understanding VOGMs and expanding the available therapeutic arsenal.

Introduction : Intracranial ateriovenous malformation (AVM) is a non-neoplastic congenital vascular abnormality which appears as a mass lesion composed of tangled blood vessels connecting arteries and veins in the brain. Case Report : Twenty seven years old male was present in our emergency department (ED) with decreased of conciousness and reccurent generalized seizure. The physical examination reveal the patient Glasgow coma scale (GCS) of 12 points (E4M5V3). Head CT scan with contrast shows contrast enhancing lesion on the frontoparietal region with extension to right lateral ventricle which suggest vascular lesion. We performed surgical resection of the AVM using the temporary clip on M2 branch which supply the nidus to reduce the risk of bleeding on operation. Discussion : Patients with grade I or II AVM tolerate resection with acceptable morbidity, whereas those with a grade IV or V AVM may be considered for conservative management because of the high anticipated risk of surgical morbidity Conclusion : AVMs are abnormalities of the intracranial vessels that constitute a connection between the arterial and venous systems and lack an intervening capillary bed. Microsurgical excision of the AVM involves a craniotomy, careful dural opening with circumferential nidus dissection until complete AVM resection is achieved.

A 33-year-old pregnant woman presented with six months of right-sided proptosis. Neuroimaging revealed a right orbital arteriovenous malformation arising from the second segment of the ophthalmic artery. As she was 9 weeks pregnant, the decision was made to monitor her closely. Over the following six months, her proptosis progressed, accompanied by decreased visual acuity, afferent pupillary defect, and red desaturation concerning for compressive optic neuropathy. After planned c-section, she underwent embolization with n-butyl cyanoacrylate. Upon awakening after embolization, she had no light perception vision from her right eye and was found to have ophthalmic artery obstruction. She ultimately developed a blind painful right eye and underwent enucleation with histopathology demonstrating glue in the central retinal artery, posterior ciliary arteries, and choroid. This case highlights ophthalmic artery occlusion as a rare complication of orbital arteriovenous malformation embolization and demonstrates correlating histopathological findings, which have not previously been reported.

Objective Combined surgical and endovascular treatment for vascular disorders has become prevalent in recent years. However, reports on one-session hybrid surgery for arteriovenous malformations (AVMs) are relatively rare. The safety and efficiency of combined treatment for brain AVMs were analyzed in biplanar hybrid operating room (OR) at one stage. Methods We retrospectively analyzed 20 patients with AVMs undergoing combined surgical and endovascular treatment from October 2015 to June 2018. The data for resection rate, microcatheter adhesion, surgical position and postoperative outcomes were analyzed. Total resection or near-total resection was achieved in all cases. Results A total of 13 patients were under combined endovascular and surgical procedures, and 7 experienced surgery with intraoperative digital subtraction angiography. Sitting position was applied in 3 of them; 2 niduses in cerebellum, and 1 in parietal lobe. Compared with admission modified Rankin Scale (mRS) in all patients, postoperative 12-month mRS showed a significant decline. Besides, 3 patients experienced microcatheter adhesion after endovascular embolization, thereafter underwent surgical adhesion removal while nidus resection was done. Conclusion Combined endovascular and surgical modality in a hybrid OR at one stage provides a safe strategy for the treatment of AVMs. The biplanar hybrid neurointerventional suite is endowed with unconstrained operating angle which enables combined endovascular and surgical treatment in sitting position. It also reduces the risk of microcatheter adhesion, which enables interventional radiologists to perform aggressively.

Acute hemorrhage caused by cerebral arteriovenous malformation (cAVM) during pregnancy is uncommon but life-threatening for both mother and fetus and presents a great challenge to clinical management. However, there is still no consensus on the treatment strategy and the treatment timing of acute hemorrhage from cAVM during pregnancy. The aim of this study was to amalgamate reported case series and our cases regarding the clinical management of pregnant patients under this special condition.We report a case series of 3 pregnant patients with acute hemorrhage caused by cAVM in our hospital. A systematic PubMed search of the English-language literature published between 1970 and 2020 was carried out. Clinical information including patients' age, gestational age, imaging studies, treatment strategy, treatment timing, delivery mode, and outcomes were collected and analyzed.The rebleed rate is about 7.1% and the mortality from rebleeding is up to 25%. Treatment modalities included radical surgery, endovascular embolization, radiosurgery/stereotactic radiosurgery, palliative surgery, and conservative treatment. There were no maternal deaths in either the intrapartum intervention group and the postpartum intervention subgroup of gestational age34 weeks.A high rebleed rate and high mortality from rebleeding indicate that the intervention of ruptured cAVM should not be delayed. Intervention of ruptured cAVM within 2 weeks after initial hemorrhage is advisable in patients at gestational age34 weeks, whereas termination of pregnancy as soon as possible followed by timely intervention of ruptured cAVM is practicable in patients at gestational age ≥34 weeks.

BACKGROUND Pediatric brain arteriovenous malformations (AVMs) are a significant cause of morbidity but the role of multimodal therapy in the treatment of these lesions is not well understood. OBJECTIVE To compare the outcomes of stereotactic radiosurgery (SRS) with and without prior embolization for pediatric AVMs. METHODS We retrospectively evaluated the International Radiosurgery Research Foundation pediatric AVM database. AVMs were categorized, based on use of pre-embolization (E + SRS) or lack thereof (SRS-only). Outcomes were compared in unadjusted and inverse probability weight (IPW)-adjusted models. Favorable outcome was defined as obliteration without post-SRS hemorrhage or permanent radiation-induced changes (RIC). RESULTS The E + SRS and SRS-only cohorts comprised 91 and 448 patients, respectively. In unadjusted models, the SRS-only cohort had higher rates of obliteration (68.5% vs 43.3%

The most common causes of hematomyelia are vascular anomalies, arteriovenous malformations, vasculitis, traumas, and conditions leading to hypocoagulation. In the presented clinical observations, hematomyelia developed against the background of anticoagulant administration and disruption of arteriovenous malformation. The disease manifests itself acutely, and the clinical picture depends on the level of spinal cord injury. Diagnosis of hematomyelia is straightforward and is based on neuroimaging by means of magnetic resonance imaging (MRI). There is no eff ective pathogenetic pharmacological therapy for hematomyelia; treatment is aimed at complications prevention. Taking in consideration the presence of a disabling neurologic impairment, this category of patients experiences an increased risk of venous thromboembolic disorders development, including fatal pulmonary embolism. In this regard, early measures are needed to prevent the development of venous thrombosis. The straightforward procedure of treatment is neurosurgical intervention in order to eliminate the source of bleeding and prevent repeated intramedullary hemorrhages. Timely diagnosis of hematomyelia followed by neurosurgical intervention leads to a favorable outcome of the disease, a decrease in mortality and disability.

Vascular malformations are present in a great variety of congenital syndromes, either as the predominant or additional feature. They pose a major challenge to the clinician: due to significant phenotype overlap, a precise diagnosis is often difficult to obtain, some of the malformations carry a risk of life threatening complications and, for many entities, treatment is not well established. To facilitate their recognition and aid in differentiation, we present a selection of notable congenital disorders of vascular system development, distinguishing between the heritable germinal and sporadic somatic mutations as their causes. Clinical features, genetic background and comprehensible description of molecular mechanisms is provided for each entity.

A 39-year-old woman presented with bleeding 4 months after a surgical termination of pregnancy. Persistent beta-human chorionic gonadotropin levels were suggestive of retained products of conception (RPOC). However, multimodal imaging revealed a concurrent uterine arteriovenous malformation (AVM). Although most stable AVMs can be managed conservatively, the need for surgical management of chronic RPOC and consequential hemorrhage risk complicates this approach. Patient-determined management prioritized blood conservation while minimizing risks to fertility. This case is discussed with respect to the rare concurrent existence of RPOC and AVM. Little is known regarding the optimal tandem therapeutic approach. As depicted, successful treatment requires careful diagnostic workup and a multidisciplinary approach.

Cerebrovascular malformations occur in both sporadic and inherited patterns. This paper reviews imaging and clinical features of cerebrovascular malformations with a genetic basis. Genetic diseases such as familial cerebral cavernous malformations and hereditary hemorrhagic telangiectasia often have manifestations in bone, skin, eyes, and visceral organs, which should be recognized. Genetic and molecular mechanisms underlying the inherited disorders are becoming better understood, and treatments are likely to follow. An interaction between the intestinal microbiome and formation of cerebral cavernous malformations has emerged, with possible treatment implications. Two-hit mechanisms are involved in these disorders, and additional triggering mechanisms are part of the development of malformations. Hereditary hemorrhagic telangiectasia encompasses a variety of vascular malformations, with widely varying risks, and a more recently recognized association with cortical malformations. Somatic mutations are implicated in the genesis of some sporadic malformations, which means that discoveries related to inherited disorders may aid treatment of sporadic cases. This paper summarizes the current state of knowledge of these conditions, salient features regarding mechanisms of development, and treatment prospects.