Search

Endoglin (ENG) mutation causes type 1 hereditary hemorrhagic telangiectasia (HHT1). HHT1 patients have arteriovenous malformations (AVMs) in multiple organs, including the brain. In mice, Eng deletion induced by R26RCreER or SM22αCre leads to AVM development in the brain and other organs. We hypothesized that an increase in Eng- negative ECs will enhance AVM severity. To increase EC Eng deletion, we used a codon-improved cre (icre), which is more potent in recombination of the floxed alleles than the wild-type (WT) cre. R26RCreER;Engf/f mice that have a Rosa promoter driving and tamoxifen (TM)-inducible WT cre expression globally, and PdgfbiCreER;Engf/f mice that have a Pdgfb promoter driving and TM-inducible icre expression in ECs were treated with three intra-peritoneal injections of TM (2.5 mg/25 g of body weight) to delete Eng globally or in the ECs. AAV-VEGF was stereotactically injected into the brain to induce brain focal angiogenesis and brain AVM. We found that icre caused more Eng deletion in the brain, indicated by a lower level of Eng proteins (p < 0.001) and fewer Eng-positive ECs (p = 0.01) than mice with WT cre. Mice with icre-mediated Eng deletion have more abnormal vessels (p = 0.02), CD68+ macrophages (p = 0.002), and hemorrhage (p = 0.04) and less vascular pericyte and smooth muscle coverage than mice with WT cre. In addition, arteriovenous shunts were detected in the intestines of icre mice, a phenotype that has not been detected in WT cre mice before. RNA-seq analysis showed that 8 out of the 10 top upregulated pathways identified by gene ontology (GO) analysis are related to inflammation. Therefore, the increase in Eng deletion in ECs exacerbates AVM severity, which is associated with enhanced inflammation. Strategies that can reduce Eng-negative ECs could be used to develop new therapies to reduce AVM severity for HHT1 patients.

Background: The increase in the collagen I (COL I)/COL III ratio enhances vessel wall stiffness and renders vessels less resistant to blood flow and pressure changes. Activated microglia enhance inflammation-induced fibrosis. Hypotheses: The COL I/COL III ratio in human and mouse brain arteriovenous malformations (bAVMs) is associated with bAVM hemorrhage, and the depletion of microglia decreases the COL I/COL III ratio and hemorrhage. Method: COL I, COL III, and hemorrhages were analyzed in 12 human bAVMs and 6 control brains, and mouse bAVMs induced in three mouse lines with activin receptor-like kinase 1 (n = 7) or endoglin (n = 7) deleted in the endothelial cells or brain focally (n = 5). The controls for the mouse study were no-gene-deleted litter mates. Mouse bAVMs were used to test the relationships between the Col I/Col III ratio and hemorrhage and whether the transient depletion of microglia reduces the Col I/Col III ratio and hemorrhage. Results: The COL I/COL III ratio was higher in the human and mouse bAVMs than in controls. The microhemorrhage in mouse bAVMs was positively correlated with the Col I/Col III ratio. Transient depletion of microglia reduced the Col I/Col III ratio and microhemorrhage. Conclusions: The COL I/COL III ratio in the bAVMs was associated with bAVM hemorrhage. The depletion of microglia reduced the bAVM Col I/Col III ratio and hemorrhage.

Background: Brain arteriovenous malformations (AVMs) are challenging vascular lesions. Extensive follow-up studies are necessary to refine the therapeutic algorithm, and to improve long-term survival in these patients. The aim of the study was to assess surgical outcomes, and to evaluate overall long-term mortality in patients treated for brain AVMs. Methods: This retrospective single-center study included 191 patients with brain AVMs, admitted between 2012 and 2022. Clinical and angiographical particularities have been analyzed, to identify factors that might influence early outcome and overall long-term mortality. Results: Out of 79 patients undergoing surgery, 51 had ruptured AVMs with total resection achieved in 68 cases (86.1%). Deep venous drainage was associated with incomplete resection. Female sex, admission modified Rankin Scale (mRS) > 2, and eloquent location were independent predictors of poor outcomes. Multiple venous drainage was associated with a higher risk of worsened early outcome. Eloquent brain region involvement, conservative treatment, increasing age, admission mRS > 2, and comorbidities significantly decrease survival in brain AVM patients. Patients treated with interventional treatments had significantly better survival than the conservatively managed ones, when adjusting for age and admission mRS. Conclusion: The study identified female sex, poor neurologic status on admission and eloquence as independent prognostic factors for a negative outcome after surgery. Patients who received interventional treatment had significantly better survival than patients managed conservatively. We recommend employing tailored, proactive management strategies as they significantly enhance longterm survival in brain AVM patients. [ABSTRACT FROM AUTHOR]

Pediatric intracranial arteriovenous malformation (AVM) patients are commonly admitted to the emergency room (ER). Increasing patient utilization of the ER has been associated with healthcare disparities and a trend of decreased efficiency. The aim of this study was to evaluate the trends of pediatric AVM ER admissions over recent years and identify factors associated with health care resource utilization and outcomes. The 2016–2019 National Inpatient Sample was queried for patients under the age of 18 admitted with AVM. Cases of admission through the ER were identified. Demographic and severity factors associated with ER admission were explored using comparative and regression statistics. Of 3875 pediatric patients with AVM admitted between 2016 and 2019, 1280 (33.0%) were admitted via the ER. Patients admitted via the ER were more likely to be in the lowest median income category (P < 0.001), on Medicaid insurance (P = 0.008), or in the South (P < 0.001) than patients admitted otherwise. There was increased severity and increased rates of intracranial hemorrhage (ICH) in patients admitted via the ER (P < 0.001). Finally, there were increasing trends in ER admissions and ICH throughout the years. ER admission of pediatric AVM patients with ICH is increasing and is associated with a distinct socioeconomic profile and increased healthcare resource utilization. These findings may reflect decreased access to more advanced diagnostic modalities, primary care, and other important resources. Identifying populations with barriers to care is likely an important component of policy aimed at decreasing the risk of severe disease presentation. [ABSTRACT FROM AUTHOR]

Objective: Gamma Knife radiosurgery (GKRS) is an effective and noninvasive treatment for high-risk arteriovenous malformations (AVMs). Since differences in GKRS outcomes by nidus type are unknown, this study evaluated GKRS feasibility and safety in patients with brain AVMs. Methods: This single-center retrospective study included patients with AVM who underwent GKRS between 2008 and 2021. Patients were divided into compact- and diffuse-type groups according to nidus characteristics. We excluded patients who performed GKRS and did not follow-up evaluation with magnetic resonance imaging or digital subtraction angiography within 36 months from the study. We used univariate and multivariate analyses to characterize associations of nidus type with obliteration rate and GKRS-related complications. Results: We enrolled 154 patients (mean age, 32.14±17.17 years; mean post-GKRS follow-up, 52.10±33.67 months) of whom 131 (85.1%) had compact- and 23 (14.9%) diffuse-type nidus AVMs. Of all AVMs, 89 (57.8%) were unruptured, and 65 (42.2%) had ruptured. The mean Spetzler-Martin AVM grades were 2.03±0.95 and 3.39±1.23 for the compact- and diffuse-type groups, respectively (p<0.001). During the follow-up period, AVM-related hemorrhages occurred in four individuals (2.6%), three of whom had compact nidi. Substantial radiation-induced changes and cyst formation were observed in 21 (13.6%) and one patient (0.6%), respectively. The AVM complete obliteration rate was 46.1% across both groups. Post-GKRS complication and complete obliteration rates were not significantly different between nidus types. For diffuse-type nidus AVMs, larger AVM size and volume (p<0.001), lower radiation dose (p<0.001), eloquent area location (p=0.015), and higher Spetzler-Martin grade (p<0.001) were observed. Conclusion: GKRS is a safe and feasible treatment for brain AVMs characterized by both diffuse- and compact-type nidi. [ABSTRACT FROM AUTHOR]

Copyright of Turkiye Klinikleri Journal of Dental Sciences is the property of Turkiye Klinikleri and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Brain arteriovenous malformations (AVM) present complex treatment decisions, particularly for low-grade AVM where surgical resection is often considered the standard. This case report emphasizes the importance of patient preferences and cultural considerations in selecting endovascular embolization over traditional surgical approaches for Spetzler-Martin Grade I AVM management, highlighting the evolving practice of patient-centered care in neurointervention. A 30-year-old male presented with recurrent seizures, characterized by a sudden onset of headache followed by speech arrest, without any preceding medical history of neurological deficits. Initial physical examination revealed no focal neurological deficits. Non-contrast computed tomography, magnetic resonance imaging, and magnetic resonance angiography suggested an AVM involving the cortical-subcortical regions of the left frontal lobe, measuring approximately 1.7 × 2.6 × 1.5 cm, fed by the left middle cerebral artery M3 segment, and draining into the superior sagittal sinus. Spetzler-Martin Grade I classification was confirmed via digital subtraction angiography. Given the patient's strong preference against invasive procedures, driven by personal and cultural beliefs, endovascular embolization was selected as the treatment strategy. Post-embolization, the patient showed marked symptomatic improvement with no evidence of residual AVM on follow-up imaging, and no postprocedure complications were reported. This case highlights the importance of considering patient preferences in AVM treatment planning, illustrating that endovascular embolization can be an effective and less invasive alternative to surgery in selected patients, reinforcing the need for personalized, patient-centered approaches in neurointerventional care.

Background: Cerebral arteriovenous malformations (AVMs) are complex, heterogeneous, uncommon lesions that carry a high risk of intracranial hemorrhage with subsequent disability. Aim: To evaluate the outcome of patients with cerebral AVMs treated in our center, King Faisal Specialized Hospital and Research Center (KFSH&RC) Saudi Arabia with SRS using the CyberKnife. Methods: Medical records of patients treated in the above-mentioned way in the period between 2009-2021 were retrospectively evaluated. Results: A total of 51 patients were included in this study. The median age at diagnosis was 31 (3-77) years. Neurological alteration and intracranial hemorrhage were the most common presentations in 24 (47.1%) patients. The mean maximum AVM nidus diameter and volume were 2.9 cm and 5.9 cc respectively. All the patients received SRS using CyberKnife with a median marginal dose of 20 (14-21) Gy over a single fraction. Volume staged treatment was applied in 4 (7.8%) patients. After a median follow-up of 37 (2-170) months, all patients were alive with successful obliteration of the AVM nidus occurring in 31 (60.8%) patients after a median latency period of 27 (4-68.9) months in those who achieved complete obliteration. No patients developed post-SRS hemorrhage and 11 (21.6%) patients developed post-SRS radiological radiation-induced changes of which only 3 (27.3%) patients were symptomatic (in the form of uncontrolled seizures). only SRS dose > 19 Gy was significantly correlated with the obliteration rate, as 79.3% of patients who received SRS dose > 19 Gy achieved obliteration vs 36.4 % only in those who received dose Conclusion: SRS treatment using CyberKnife is effective management for patients with cerebral AVMs without an increase in the incidence of post-SRS hemorrhage, stroke, or death.

We present a case of successful embolization of an anterior chest wall arteriovenous malformation (AVM) in a 24-year-old male patient. This report aims to highlight the efficacy and safety of using the liquid embolic agent (onyx) as well as the combined approaches (trans-femoral and trans-radial) in managing rare complex chest wall AVMs.

Arteriovenous malformations (AVMs) are complex vascular lesions most commonly found in the brain and infrequently found in the head and neck. AVMs are characterized by a tangle of blood vessels called a nidus, which shunts blood from an artery directly to a draining vein. Various treatments are available, including surgical resection and endovascular embolization. Here, we report the case of a 32-year-old male patient who complained of painful pulsating left neck swelling with dysphagia for 1 year, which turned out to be an AVM alongside the left thyroid gland. The AVM was treated by embolization using Onyx in 2 sessions. The patient has been free of symptoms since the treatment.

Abstract Background Clinically, arteriovenous malformations in the buttocks (bAVMs) are extremely rare. Our study aimed to evaluate the efficacy and safety of ethanol embolotherapy in managing bAVMs. Results A total of 32 patients with bAVMs (14 females and 18 males) from 2012 to 2021 were included in this study. All patients underwent complete clinical and imaging examinations. Further, the AVMs lesions were analyzed according to Schöbinger staging and Yakes classification. Each patient had undergone a multistage ethanol embolization. The amelioration of clinical symptoms and devascularization on angiography were evaluated at regular follow-ups. In the present cohort, the 11–20 age group had the most patients (15/32; 46.88%). A total of 124 embolization procedures were performed (average 3.88 procedures per patient), and the average dose of absolute ethanol was 18.96 mL per procedure. Thirteen patients with dominant draining veins underwent additional coil deployment before ethanol embolization (13/32; 40.63%). During follow-ups, clinical improvement was found in 23 of 27 who presented with a pulsating mass (85.19%), 17 of 20 with abnormal local skin temperature (85%), 5 of 6 with bleeding (83.33%), and 5 of 5 patients treated for pain (100%). More than 75% angiographic devascularization was achieved in 18 patients (18/32; 56.25%). Finally, 12 out of 13 patients (92.31%) reduced from Schöbinger Stage III to a lower grade, and ten patients exhibited a complete response (10/32; 31.23%). There was a single serious complication of local necrosis, while neither paranesthesia nor infection was observed postoperatively. Conclusions Ethanol embolization assisted with coils can treat bAVMs effectively and safely. The Yakes classification contributed to the optimal ethanol embolotherapy of bAVMs.

Abstract Background Osler-Weber-Rendu syndrome (OWRS) is an autosomal dominant disease with recurrent epistaxis, mucocutaneous telangiectasias, and arteriovenous malformations. Its clinical presentation ranges from simple skin lesions to life-threatening complications. When the diagnosis of the disease is delayed, it can be mortal and have high morbidity. This case is presented because OWRS is rare, and although she has all the features of the disease, she was diagnosed in the geriatric age group. Case presentation A 72-year-old female patient who applied to the emergency department with the complaint of melena was diagnosed with upper gastrointestinal system bleeding. Gastroscopy revealed angiodysplasia in the bulb. Colonoscopy was normal. She had telangiectasias on her face, maxilla, nose, tongue and lips. She also had recurrent epistaxis and a family history. Thorax CT showed aneurysmatic vascular malformations in the lung. Abdominal MRI revealed vascular malformations in the liver. Brain MRI was normal. The patient was diagnosed with OWRS according to the Curaçao diagnostic criteria because of telangiectasia in the mouth, nose, and face, angiodysplasia in the gastric bulb, aneurysmatic vascular dilatation in the lung, vascular pathologies in the liver, and a history of epistaxis and telangiectasia in the patient’s family members. Conclusion This patient is presented because OWRS is rare, and although she has all the features of the disease, she was diagnosed in the geriatric age group. Clinicians should be aware of this rare disease. Especially in the elderly, when angiodysplasia causing gastrointestinal bleeding is detected, it should be considered in the differential diagnosis that this may be an OWSR case.

Background: Cerebral arteriovenous malformations (AVMs) are complex, heterogeneous, uncommon lesions that carry a high risk of intracranial hemorrhage with subsequent disability. Aim: To evaluate the outcome of patients with cerebral AVMs treated in our center, King Faisal Specialized Hospital and Research Center (KFSH&RC) Saudi Arabia with SRS using the CyberKnife. Methods: Medical records of patients treated in the above-mentioned way in the period between 2009-2021 were retrospectively evaluated. Results: A total of 51 patients were included in this study. The median age at diagnosis was 31 (3-77) years. Neurological alteration and intracranial hemorrhage were the most common presentations in 24 (47.1%) patients. The mean maximum AVM nidus diameter and volume were 2.9 cm and 5.9 cc respectively. All the patients received SRS using CyberKnife with a median marginal dose of 20 (14-21) Gy over a single fraction. Volume staged treatment was applied in 4 (7.8%) patients. After a median follow-up of 37 (2-170) months, all patients were alive with successful obliteration of the AVM nidus occurring in 31 (60.8%) patients after a median latency period of 27 (4-68.9) months in those who achieved complete obliteration. No patients developed post-SRS hemorrhage and 11 (21.6%) patients developed post-SRS radiological radiation-induced changes of which only 3 (27.3%) patients were symptomatic (in the form of uncontrolled seizures). only SRS dose > 19 Gy was significantly correlated with the obliteration rate, as 79.3% of patients who received SRS dose > 19 Gy achieved obliteration vs 36.4 % only in those who received dose <19 Gy, p value 0.002. Conclusion: SRS treatment using CyberKnife is effective management for patients with cerebral AVMs without an increase in the incidence of post-SRS hemorrhage, stroke, or death. [ABSTRACT FROM AUTHOR]

Background: Clinically, arteriovenous malformations in the buttocks (bAVMs) are extremely rare. Our study aimed to evaluate the efficacy and safety of ethanol embolotherapy in managing bAVMs. Results: A total of 32 patients with bAVMs (14 females and 18 males) from 2012 to 2021 were included in this study. All patients underwent complete clinical and imaging examinations. Further, the AVMs lesions were analyzed according to Schöbinger staging and Yakes classification. Each patient had undergone a multistage ethanol embolization. The amelioration of clinical symptoms and devascularization on angiography were evaluated at regular follow-ups. In the present cohort, the 11–20 age group had the most patients (15/32; 46.88%). A total of 124 embolization procedures were performed (average 3.88 procedures per patient), and the average dose of absolute ethanol was 18.96 mL per procedure. Thirteen patients with dominant draining veins underwent additional coil deployment before ethanol embolization (13/32; 40.63%). During follow-ups, clinical improvement was found in 23 of 27 who presented with a pulsating mass (85.19%), 17 of 20 with abnormal local skin temperature (85%), 5 of 6 with bleeding (83.33%), and 5 of 5 patients treated for pain (100%). More than 75% angiographic devascularization was achieved in 18 patients (18/32; 56.25%). Finally, 12 out of 13 patients (92.31%) reduced from Schöbinger Stage III to a lower grade, and ten patients exhibited a complete response (10/32; 31.23%). There was a single serious complication of local necrosis, while neither paranesthesia nor infection was observed postoperatively. Conclusions: Ethanol embolization assisted with coils can treat bAVMs effectively and safely. The Yakes classification contributed to the optimal ethanol embolotherapy of bAVMs. [ABSTRACT FROM AUTHOR]

Intracranial vascular malformations typically encountered by pediatric neurosurgeons include arteriovenous malformations, vein of Galen malformations and cavernous malformations. While these remain amongst some of the most challenging lesions faced by patients and caregivers, the past decade has produced marked advances in the understanding of the pathophysiology of these conditions, with concomitant innovations in treatment. This article will highlight present and future perspectives relevant to these diseases, with a focus on an emerging approach utilizing disease-specific mutations to develop a novel taxonomy for these conditions. [ABSTRACT FROM AUTHOR]

Pediatric intracranial arteriovenous malformations (AVMs) are challenging lesions managed by pediatric neurosurgeons. The high risk of hemorrhage and neurologic injury is compounded by the unique anatomy of each malformation that requires individualizing treatment options. This article reviews the current status of pediatric AVM epidemiology, pathophysiology and clinical care, with a specific focus on the rationale and methodology of surgical resection. [ABSTRACT FROM AUTHOR]

Brain arteriovenous malformations (bAVMs) are aberrant arteriovenous shunts through a vascular nidus with no intervening capillary beds. They are one of the commonest causes of spontaneous intracranial haemorrhage in children and may be associated with significant morbidity and mortality in cases of rupture. Treatment strategies include microsurgical resection, endovascular embolisation, stereotactic radiosurgery, multimodality treatment with a combination thereof, and particularly in high-grade bAVMs, conservative management. Clinicians involved in treating bAVMs need to have familiarity with the natural history pertaining to bAVMs in terms of risk of rupture, risk factors elevating rupture risk as well as understanding the clinical manifestations of bAVMs. This invited review serves to provide a synthesis on natural history and clinical presentation of bAVMs with particular focus in children to inform decision-making pertaining to management. [ABSTRACT FROM AUTHOR]

Vascular anomalies are vascular lesions that are present from childhood. They are classified into tumours or malformations based on clinical and histological features. Benign infantile haemangiomas are the most common vascular tumour and have a predictable self-limiting course. Rarer vascular tumours exist, and some may cause platelet consumption. Management is usually conservative, with active treatment reserved for functional or cosmetic complications (ulceration, or obstruction and distortion of vital structures). Oral propranolol is useful for troublesome lesions. Vascular malformations are structural anomalies of vascular morphogenesis present at birth without cellular proliferation that, in general, grow with the patient. They are sub-classified by vessel type as 'low flow' (capillary, lymphatic and venous) and 'high flow' (arteriovenous) or lesions with a combination of vessel type. They become problematic under certain circumstances, usually puberty and also pregnancy. The most troublesome are extensive lesions, especially venous and arteriovenous. Their effects may be cosmetic, those of a space-occupying lesion, infection, bleeding, pain or coagulopathy. Venous lesions cause consumptive coagulopathy, sometimes with life-threatening risks. Treatment options include medication and symptom control with antibiotics, analgesia, control of menses, compression garments and intervention with laser (capillary type), sclerotherapy, embolization and/or surgical excision. Patients with complex lesions are best managed by a multidisciplinary team and all surgical sub-specialties may be involved. [ABSTRACT FROM AUTHOR]

Congenital vascular malformations (CVMs) are the result of an aberrant development during embryogenesis. Although these lesions are present at birth, they are not always visible yet. Once symptomatic, patients suffer from pain, bleeding, ulcers, infections or lymphatic leakage, depending on the subtype of vessels involved. Treatment includes conservative management, surgery, sclerotherapy, embolization and pharmacological therapy. The clinical presentation varies widely and treatment can be challenging due to the rarity of the disease and potential difficulties of treatment. This review gives an overview of the historical developments in diagnosis and classification and exposes the key elements of innovations in the past decades on the identification of genetic mutations and personalized treatment. These advances in the field and a multidisciplinary approach are highly valuable in the optimization of clinical care aimed at both curing or stabilizing the CVM and pursuing physical and psychosocial wellbeing. [ABSTRACT FROM AUTHOR]

Background: Osler-Weber-Rendu syndrome (OWRS) is an autosomal dominant disease with recurrent epistaxis, mucocutaneous telangiectasias, and arteriovenous malformations. Its clinical presentation ranges from simple skin lesions to life-threatening complications. When the diagnosis of the disease is delayed, it can be mortal and have high morbidity. This case is presented because OWRS is rare, and although she has all the features of the disease, she was diagnosed in the geriatric age group. Case presentation: A 72-year-old female patient who applied to the emergency department with the complaint of melena was diagnosed with upper gastrointestinal system bleeding. Gastroscopy revealed angiodysplasia in the bulb. Colonoscopy was normal. She had telangiectasias on her face, maxilla, nose, tongue and lips. She also had recurrent epistaxis and a family history. Thorax CT showed aneurysmatic vascular malformations in the lung. Abdominal MRI revealed vascular malformations in the liver. Brain MRI was normal. The patient was diagnosed with OWRS according to the Curaçao diagnostic criteria because of telangiectasia in the mouth, nose, and face, angiodysplasia in the gastric bulb, aneurysmatic vascular dilatation in the lung, vascular pathologies in the liver, and a history of epistaxis and telangiectasia in the patient's family members. Conclusion: This patient is presented because OWRS is rare, and although she has all the features of the disease, she was diagnosed in the geriatric age group. Clinicians should be aware of this rare disease. Especially in the elderly, when angiodysplasia causing gastrointestinal bleeding is detected, it should be considered in the differential diagnosis that this may be an OWSR case. [ABSTRACT FROM AUTHOR]

Arteriovenous malformations (AVMs) are vascular malformations of the central nervous system (CNS) with potential for significant consequences. The exact pathophysiologic mechanism of AVM formation is not fully understood. This study aims to evaluate bibliometric parameters and citations of the literature of AVMs to provide an overview of how the field has evolved. We performed an electronic search on Web of Science to identify the top 100 published and indexed articles with the highest number of citations discussing the pathogenesis of AVMs. This study yielded 1863 articles, of which the top 100 were selected based on the highest total citation count. These articles included 24% basic science, 46% clinical, and 30% review articles. The most-cited article was a clinical article from 2003, and the most recent was published in 2022. The median number of authors was 6, with the highest being 46 for a clinical article. The top 5 journals were identified, with the highest impact factor being 20.1. 13 countries were identified, with the US contributing the most articles (approximately 70%). Regarding genes of investigation, VEGF was one of the early genes investigated, while more interested in RAS/MAPK has been garnered since 2015. There is a growing interest in AVM genomics and pathogenesis research. While progress has been made in understanding clinical aspects and risk factors, the exact pathophysiological mechanisms and genetic basis of AVM formation remain incompletely understood. Further investigation of key genes in AVM pathogenesis can allow identification of potential therapeutic targets. [ABSTRACT FROM AUTHOR]

Objective: To analyze the outcomes of hypofractionated stereotactic radiotherapy (HFSRT) for Spetzler Martin grades 4 and 5 arteriovenous malformations (AVMs) in a pediatric population. Methods: Fourteen patients with Spetzler Martin (SM) grades IV and V large AVMs who underwent HFSRT between January 2013 and July 2019 were retrospectively reviewed. All patients received HFSRT at a dose of 30–36 Gy in 5 to 6 fractions. They were followed up annually with clinical and imaging assessments to evaluate obliteration rates. Results: The median age at presentation was 15 years (range 8–21 years). Ten (71%) were SM grade 4 AVMs and the rest were SM grade 5 AVMs. The majority presented with headache (8 [57%]), and 3 (21%) presented with bleeding. The median nidus volume was 39.4 cc (IQR, 31.4–52.4). Two (14%) patients had infratentorial AVMs. All of them had deep venous drainage. The median clinical follow-up duration was 75 months (range 31–107 months). There was complete obliteration of the nidus in 3 (21%) patients with a median time to obliteration of 39 months. HFSRT resulted in a reduction of the AVM volume to 12 cc or less in nearly 70% of patients. None of the patients experienced re-bleeding. 79% reported an improvement in their symptoms. Conclusion: HFSRT is a highly effective treatment for high-grade AVMs in children, which can result in either complete elimination or significant reduction of the nidus volume or make it suitable for additional treatment, such as single-session stereotactic radiosurgery (SRS). [ABSTRACT FROM AUTHOR]

Hereditary hemorrhagic telangiectasia (HHT), also known as Osler–Rendu–Weber syndrome, is a rare autosomal dominant disorder characterized by vascular malformations. This comprehensive review aimed to provide an overview and summarize various aspects of HHT, including the genetic abnormalities, complications associated with visceral arteriovenous malformations (AVMs), prognosis of HHT, quality of life (QOL), and treatment of epistaxis. In addition, this review highlights the challenges in diagnosing HHT and emphasizes the critical role of otolaryngologists in the early detection of HHT. Otolaryngologists can refer patients with refractory epistaxis for AVM screening to expedite intervention. Mutation of the genes involved in the transforming growth factor-β signaling pathway leads to the incidence of HHT, resulting in the formation of abnormal blood vessel formation. These vascular malformations commonly manifest as telangiectasia on the skin and mucous membranes; however, epistaxis remains the hallmark symptom of HHT. The impact of HHT goes beyond the visible symptoms and often includes the formation of life-threatening visceral AVMs in the lungs, liver, and brain. The prognosis of patients with HHT is closely related to the development of these complications, necessitating timely diagnosis and intervention. Refractory epistaxis diminishes the QOL of patients with HHT. The management of epistaxis ranges from conservative measures to advanced interventions such as prevention, conservative treatments, ablation, surgical procedures, and the administration of anti-angiogenic agents. However, effective management requires a multidisciplinary approach. The diagnosis of HHT remains challenging due to its variable presentation and lack of awareness among physicians. This review highlights the importance of reducing the duration between symptom onset and diagnosis. Otolaryngologists who are experienced in the management of refractory epistaxis can aid in identifying potential cases of HHT. They can facilitate the initiation of screening for visceral AVMs via prompt recognition of the signs and symptoms of HHT, contributing to improved patient outcomes. Early detection and intervention through screening can extend the life expectancy of patients with HHT to levels comparable with that of the general population. In conclusion, this review provides insight into various aspects of HHT and emphasizes the importance of timely diagnosis and intervention in the mitigation of the potentially life-threatening complications associated with this disorder. Otolaryngologists play a critical role in this process, serving as gatekeepers to the identification of cases of HHT and implementation of appropriate screening and management pathways, thereby improving the life expectancy and QOL of patients. [ABSTRACT FROM AUTHOR]

ObjectivesThe objective of this study is to evaluate the user-defined optimization settings in the Fast Inverse Planning (FIP) optimizer in Leksell GammaPlan® and determine the parameters that result in the best stereotactic radiosurgery (SRS) plan quality for brain metastases, benign tumors, and arteriovenous malformations (AVMs).MethodsThirty patients with metastases and 30 with benign lesions-vestibular schwannoma, AVMs, pituitary adenoma, and meningioma-treated with SRS were evaluated. Each target was planned by varying the low dose (LD) and beam-on-time (BOT) penalties in increments of 0.1, from 0 to 1. The following plan quality metrics were recorded for each plan: Paddick conformity index (PCI), gradient index (GI), BOT, and maximum organ-at-risk (OAR) doses. A novel objective score matrix was calculated for each target using a linearly weighted combination of the aforementioned metrics. A histogram of optimal solutions containing the five best scores was extracted.ResultsA total of 7260 plans were analyzed with 121 plans per patient for the range of LD/BOT penalties. The ranges of PCI, GI, and BOT across all metastatic lesions were 0.58-0.97, 2.1-3.8, and 8.8-238 min, respectively, and were 0.13-0.97, 2.1-3.8, and 8.8-238 min, respectively, for benign lesions. The objective score matrix showed unique optimal solutions for metastatic lesions and benign lesions. Additionally, the plan metrics of the optimal solutions were significantly improved compared to the clinical plans for metastatic lesions with equivalent metrics for all other cases.ConclusionIn this study, FIP optimizer was evaluated to determine the optimal solution space to maximize PCI and minimize GI, BOT and OAR doses simultaneously for single metastatic/benign/non-neoplastic targets. The optimal solution chart was determined using a novel objective score which provides novice and expert planners a roadmap to generate the most optimal plans efficiently using FIP.

Mechanisms underlying arteriovenous malformations (AVMs) are poorly understood. Using mice with endothelial cell (EC) expression of constitutively active Notch4 (Notch4*EC), we show decreased arteriolar tone in vivo during brain AVM initiation. Reduced vascular tone is a primary effect of Notch4*EC, as isolated pial arteries from asymptomatic mice exhibited reduced pressure-induced arterial tone ex vivo. The nitric oxide (NO) synthase (NOS) inhibitor NG-nitro-l-arginine (L-NNA) corrected vascular tone defects in both assays. L-NNA treatment or endothelial NOS (eNOS) gene deletion, either globally or specifically in ECs, attenuated AVM initiation, assessed by decreased AVM diameter and delayed time to moribund. Administering nitroxide antioxidant 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl also attenuated AVM initiation. Increased NOS-dependent production of hydrogen peroxide, but not NO, superoxide, or peroxynitrite was detected in isolated Notch4*EC brain vessels during AVM initiation. Our data suggest that eNOS is involved in Notch4*EC-mediated AVM formation by up-regulating hydrogen peroxide and reducing vascular tone, thereby permitting AVM initiation and progression.

BackgroundBrain arteriovenous malformations (AVMs) are challenging vascular lesions. Extensive follow-up studies are necessary to refine the therapeutic algorithm, and to improve long-term survival in these patients. The aim of the study was to assess surgical outcomes, and to evaluate overall long-term mortality in patients treated for brain AVMs.MethodsThis retrospective single-center study included 191 patients with brain AVMs, admitted between 2012 and 2022. Clinical and angiographical particularities have been analyzed, to identify factors that might influence early outcome and overall long-term mortality.ResultsOut of 79 patients undergoing surgery, 51 had ruptured AVMs with total resection achieved in 68 cases (86.1%). Deep venous drainage was associated with incomplete resection. Female sex, admission modified Rankin Scale (mRS) > 2, and eloquent location were independent predictors of poor outcomes. Multiple venous drainage was associated with a higher risk of worsened early outcome. Eloquent brain region involvement, conservative treatment, increasing age, admission mRS > 2, and comorbidities significantly decrease survival in brain AVM patients. Patients treated with interventional treatments had significantly better survival than the conservatively managed ones, when adjusting for age and admission mRS.ConclusionThe study identified female sex, poor neurologic status on admission and eloquence as independent prognostic factors for a negative outcome after surgery. Patients who received interventional treatment had significantly better survival than patients managed conservatively. We recommend employing tailored, proactive management strategies as they significantly enhance long-term survival in brain AVM patients.

Arteriovenous malformations (AVMs) are uncommon inborn vascular anomaly, making for about 1.5% of all vascular aberrations. Remarkably, approximately half of AVM cases manifest in the mouth cavity and faciomaxillary region. A female patient, age 18 with an AVM on the right side of her face, is the subject of this case report. She had soft, compressible, nontender swelling on the right side of her face since birth; this swelling had gotten worse with age and she had surgery for it when she was 8 years old. The three-dimensional computed tomography scan of the face with angiography was done with findings of heterogeneous soft-tissue density lesion with increased volume, measuring 7.15 cm × 3.2 cm × 6.23 cm involving the right cheek. The surgery was planned through an intraoral approach over the right buccal mucosa with surgical excision and debulking with primary closure with the remaining buccal mucosa was done. Then, the patient kept on follow-up and the potential results were observed.

Upregulation of Notch signaling is associated with brain arteriovenous malformation (bAVM), a disease that lacks pharmacological treatments. Tetracycline (tet)-regulatable endothelial expression of constitutively active Notch4 (Notch4*tetEC) from birth induced bAVMs in 100% of mice by P16. To test whether targeting downstream signaling, while sustaining the causal Notch4*tetEC expression, induces AVM normalization, we deleted Rbpj, a mediator of Notch signaling, in endothelium from P16, by combining tet-repressible Notch4*tetEC with tamoxifen-inducible Rbpj deletion. Established pathologies, including AV connection diameter, AV shunting, vessel tortuosity, intracerebral hemorrhage, tissue hypoxia, life expectancy, and arterial marker expression were improved, compared with Notch4*tetEC mice without Rbpj deletion. Similarly, Rbpj deletion from P21 induced advanced bAVM regression. After complete AVM normalization induced by repression of Notch4*tetEC, virtually no bAVM relapsed, despite Notch4*tetEC re-expression in adults. Thus, inhibition of endothelial Rbpj halted Notch4*tetEC bAVM progression, normalized bAVM abnormalities, and restored microcirculation, providing proof of concept for targeting a downstream mediator to treat AVM pathologies despite a sustained causal molecular lesion.

Objective ‒ to evaluate the results of treatment of patients with extra-trunk (diffuse) venous malformations (VM) and microfistulous arteriovenous malformations (AVM) of superficial localization, to whom the technique of sclerotherapy was applied, by direct puncture of the «node» of the malformation and a combination of endovascular embolization with sclerotherapy. Determine the criteria for using the sclerosation method as monotherapy or in combination with embolization. Materials and methods. In the period from 2017 to 2023, 47 patients (22 (46.8 %) men and 25 (53.2 %) women) with VM (n=27) and AVM (n=20) located superficially were examined and treated were treated for the malformation using sclerosation. The age of the patients ranged from 5 to 67 years, the average age ‒ (28.9 ± 7.4) years. Pathology localization: head and neck – 31, upper extremity – 6, lower extremity – 7, trunk – 3. In 17 patients, sclerotherapy was used as monotherapy, 30 patients underwent a combination of sclerotherapy with embolization The observation period ranged from 6 months to 8 years, the average observation period was (5.2 ± 0.98) years. Results. Out of 27 patients with VM, 17 (62.9 %) patients were diagnosed with a VM based on the results of diagnostic venography and arteriography. From 17 patients were treated with sclerotherapy as monotherapy with a satisfactory clinical result in 14 (82.3 %) patients. In 10 (37.1 %) 27 patients with VM, signs of arteriovenous shunt (AVS) were found in the structure of VM. A combination of endovascular embolization and sclerosation was used in the treatment of VM with signs of arteriovenous shunting in 10 patients. A positive effect was obtained in 7 (70.0 %) cases. AVM treatment using a combination of sclerosation and embolization was carried out in 20 patients. A satisfactory clinical result was obtained in 17 (85.0 %) patients. Treatment of 47 patients with VM and AVM was technically successful in all cases (100 %). Overall clinical improvement was obtained in 38 (81.0 %). A complication in the form of tissue necrosis in the malformation area occurred in 3 (6.4 %) patients. 43 (91.4 %) patients received 2 to 4 AVM embolization and 2 to 5 sclerotherapy sessions during the treatment period. Conclusions. According to the obtained results, sclerotherapy by direct puncture of the venous structures of malformations with the introduction of a sclerosing drug into the «node» is a safe and effective method of treating VM. In every third patient (37.1 %) with VM, signs of AVS were found in the structure of VM, which requires prior embolization of existing AVS. Preliminary embolization of the afferent arteries of AVM leads to a slowing down of the blood flow rate and enables the use of sclerotherapy techniques, maintaining the effective concentration of the drug in the «node» of the AVM. Evaluation of the results of the treatment of 47 patients with extra-trunk (diffuse) venous and microfistulous AVM of superficial localization using the methods of endovascular embolization and sclerotherapy proves that the combined use of these methods allows to improve the results and increase the effectiveness of the treatment of this complex pathology.

Background Arteriovenous malformations (AVMs) in the head and neck pose a challenge in their management due to their local aggressiveness and high recurrence risk. This study aimed to analyze literature on head and neck AVM recurrence post-treatment and identify the most effective strategy with a lower recurrence rate. Objectives To analyse existing literature on the recurrence of head and neck AVMs following treatment. Our goal was to identify the most effective treatment option with a lower recurrence rate. Methods We conducted a thorough literature search using PubMed, ScienceDirect, and Scopus, from year 2000 to the present. Our analysis focused on key endpoints, specifically the recurrence rates of head and neck AVMs following various treatment approaches. Results Out of the initial pool of 108 screened articles, a total of 83 patients were deemed suitable for inclusion in the literature review. The reviewed articles demonstrated that appropriate diagnostic tests were documented in 95% of the included studies. Among the patients, 37.3% had previously undergone interventions and were currently dealing with regrowth masses. Notably, 56.6% of patients underwent a combined approach involving both endovascular and surgical methods, while 25.3% opted for a surgical-only approach, and only 18.1% pursued an endovascular-only approach. The studies showed a promising curing rate of AVMs, with a success rate of 94%, albeit with a complication rate of 32.5%. The average follow-up duration for all patients was 26 months, with a standard deviation of 20.5 months. Out of the 83 patients, 5 experienced recurrence, with single-modality approach. Interestingly, no patients who received a multi-modality of treatments experienced recurrence or regrowth of the AVM mass within the follow up period. Conclusion The multi-modality approach outperformed single-modality treatments in preventing AVM recurrence. These findings highlight the importance of a comprehensive and multidisciplinary approach in the management of these complex vascular anomalies. PROSPERO: CRD42023490871 registered on 17/12/2023

Objective: Rare disease Background: An arteriovenous malformation (AVM) is an abnormal connection between an artery and a vein, bypassing the capillary network. An AVM of the superficial temporal artery (STA) can occur after trauma, iatrogenic injury, infection, or spontaneously. Spontaneous, or iatrogenic, presentations of STA AVM are thought to be rare, with very few reported cases. Symptoms include local pain, headache, tinnitus, or paresthesia, in addition to a palpable mass associated with thrill on palpation. Options for diagnosis include intra-arterial angiography, doppler ultrasound, magnetic resonance angiography (MRA), and computed tomography angiography (CTA). Current management options include surgical excision, ligation, and embolization; however, it is unknown which treatment is superior in terms of recurrence and which carries a lower risk of complications. Case Report: We present a case of a spontaneous STA AVM in a 76-year-old woman with past medical history significant for seasonal allergies and hyperlipidemia, who presented with pulsatile tinnitus and a palpable, tender mass located to the left temporal area. The mass had been present for several years, with gradual increase in size two to three years prior to presentation. She denied any history of trauma or procedure prior to presentation of the pulsatile mass. She underwent open excision with complete resolution of symptoms and no recurrence at 11-month follow-up. Conclusions: AVM of the STA is a condition that can occur secondary to trauma, infection, iatrogenic injury, or spontaneously. Spontaneous, or iatrogenic, presentations of STA AVM are thought to be rare, with very few cases documented in the literature. Surgical treatment remains the standard of management, with options including surgical excision, ligation, or embolization. [ABSTRACT FROM AUTHOR]

BACKGROUND: Distinct endothelial cell cycle states (early G1 versus late G1) provide different “windows of opportunity” to enable the differential expression of genes that regulate venous versus arterial specification, respectively. Endothelial cell cycle control and arteriovenous identities are disrupted in vascular malformations including arteriovenous shunts, the hallmark of hereditary hemorrhagic telangiectasia (HHT). To date, the mechanistic link between endothelial cell cycle regulation and the development of arteriovenous malformations (AVMs) in HHT is not known. METHODS: We used BMP (bone morphogenetic protein) 9/10 blocking antibodies and endothelial-specific deletion of activin A receptor like type 1 (Alk1) to induce HHT in Fucci (fluorescent ubiquitination-based cell cycle indicator) 2 mice to assess endothelial cell cycle states in AVMs. We also assessed the therapeutic potential of inducing endothelial cell cycle G1 state in HHT to prevent AVMs by repurposing the Food and Drug Administration–approved CDK (cyclin-dependent kinase) 4/6 inhibitor (CDK4/6i) palbociclib. RESULTS: We found that endothelial cell cycle state and associated gene expressions are dysregulated during the pathogenesis of vascular malformations in HHT. We also showed that palbociclib treatment prevented AVM development induced by BMP9/10 inhibition and Alk1 genetic deletion. Mechanistically, endothelial cell late G1 state induced by palbociclib modulates the expression of genes regulating arteriovenous identity, endothelial cell migration, metabolism, and VEGF-A (vascular endothelial growth factor A) and BMP9 signaling that collectively contribute to the prevention of vascular malformations. CONCLUSIONS: This study provides new insights into molecular mechanisms leading to HHT by defining how endothelial cell cycle is dysregulated in AVMs because of BMP9/10 and Alk1 signaling deficiencies, and how restoration of endothelial cell cycle control may be used to treat AVMs in patients with HHT. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Cerebrofacial arteriovenous Metameric syndrome (CAMS) typically manifests as types I, II, or III, occasionally presenting as dual types. Our unique case underscores the coexistence of all three CAMS types in one patient. Furthermore, the concurrent acute cerebellar infarct underscores the need to consider CAMS in the differential diagnosis of adolescents experiencing neurological events. [ABSTRACT FROM AUTHOR]

Extracranial arteriovenous malformations (AVMs) are regarded as rare diseases and are prone to complications such as pain, bleeding, relentless growth, and high volume of shunted blood. Due to the high vascular pressure endothelial cells of AVMs are exposed to mechanical stress. To control symptoms and lesion growth pharmacological treatment strategies are urgently needed in addition to surgery and interventional radiology. AVM cells were isolated from three patients and exposed to cyclic mechanical stretching for 24 h. Thalidomide and bevacizumab, both VEGF inhibitors, were tested for their ability to prevent the formation of circular networks and proliferation of CD31+ endothelial AVM cells. Furthermore, the effect of thalidomide and bevacizumab on stretched endothelial AVM cells was evaluated. In response to mechanical stress, VEGF gene and protein expression increased in patient AVM endothelial cells. Thalidomide and bevacizumab reduced endothelial AVM cell proliferation. Bevacizumab inhibited circular network formation of endothelial AVM cells and lowered VEGF gene and protein expression, even though the cells were exposed to mechanical stress. With promising in vitro results, bevacizumab was used to treat three patients with unresectable AVMs or to prevent regrowth after incomplete resection. Bevacizumab controlled bleeding, pulsation, and pain over the follow up of eight months with no patient-reported side effects. Overall, mechanical stress increases VEGF expression in the microenvironment of AVM cells. The monoclonal VEGF antibody bevacizumab alleviates this effect, prevents circular network formation and proliferation of AVM endothelial cells in vitro. The clinical application of bevacizumab in AVM treatment demonstrates effective symptom control with no side effects. Mechanical stress increases VEGF expression in endothelial AVM cells, possibly causing the VEGF upregulation in the microenvironment of AVM cells. The resulting RAS/RAF/MEK/ERK signaling in leads to progression of fast-flow malformations. The monoclonal VEGF-A antibody bevacizumab alleviates this effect, prevents circular network formation and proliferation of AVM endothelial cells in vitro. Sporadically occurring slow-flow malformations (LMs, VMs) have mutations in TEK or PIK3CA. TEK encodes the endothelial receptor tyrosine kinase TIE2. Sporadic extracranial fast-flow malformations (AVMs) show mutations in KRAS, BRAF and MAP2K1, which encodes the dual specificity mitogen-activated protein kinase MEK1. Combined targeting of the molecular causes of the disease could be key to achieve symptom control and reduce lesion growth. Orange: gain-of-function; Blue, circled with orange: enhanced signaling. [ABSTRACT FROM AUTHOR]

Background: Currently, there is a lack of intuitive analysis regarding the development trend, main authors, and research hotspots in the field of cerebral arteriovenous malformation treatment, as well as a detailed elaboration of possible research hotspots. Methods: A bibliometric analysis was conducted on data retrieved from the Web of Science core collection database between 2000 and 2022. The analysis was performed using R, VOSviewer, CiteSpace software, and an online bibliometric platform. Results: A total of 1,356 articles were collected, and the number of publications has increased over time. The United States and the University of Pittsburgh are the most prolific countries and institutions in the field. The top three cited authors are Kondziolka D, Sheehan JP, and Lunsford LD. The Journal of Neurosurgery and Neurosurgery are two of the most influential journals in the field of brain arteriovenous malformation treatment research, with higher H-index, total citations, and number of publications. Furthermore, the analysis of keywords indicates that "aruba trial," "randomised trial," "microsurgery," "onyx embolization," and "Spetzler-Martin grade" may become research focal points. Additionally, this paper discusses the current research status, existing issues, and potential future research directions for the treatment of brain arteriovenous malformations. Conclusion: This bibliometric study comprehensively analyses the publication trend of cerebral arteriovenous malformation treatment in the past 20 years. It covers the trend of international cooperation, publications, and research hotspots. This information provides an important reference for scholars to further study cerebral arteriovenous malformation. [ABSTRACT FROM AUTHOR]

Endovascular embolization of arteriovenous malformations (AVMs) in the brain usually requires injecting liquid embolic agents (LEAs) to reduce blood flow through the malformation. In clinical procedures, the feeding artery into which the LEAs are injected, and the amount of LEAs needs to be carefully planned preoperatively. Computational fluid dynamics can simulate the injecting process of LEAs in nidus and evaluate the therapeutic effects of different procedures preoperatively. Applying a porous media model avoided the difficulties of geometric modeling of AVMs, and the complex vascular network structure within the nidus was reproduced. The multi-phase flow was applied to simulate the interaction between LEAs and blood. The viscosity of LEAs is determined by the concentration of its solute ethylene-vinyl alcohol copolymer (EVOH). The diffusion process of the solvent dimethyl sulfoxide (DMSO) was calculated by solving the species transport equation. The coagulation of LEAs was simulated by constructing the relationship between the concentration of EVOH and viscosity. The numerical simulation method of LEAs for injection and coagulation was tested on two patient-specific AVMs. The calculations predicted the flow direction of the LEAs in the nidus. The morphology of the injected LEAs could be well visualized by 3D rendering. Quantitative analysis was conducted, including flow rate changes at the feeding arteries and draining veins. The embolization process of AVMs with LEAs can be simulated by computational fluid dynamics (CFD) methods to show the therapeutic effects of different embolization procedure planning, the optimal treatment plan can be determined. [ABSTRACT FROM AUTHOR]

Purpose: Treatment of brain arteriovenous malformation (bAVM) includes microsurgical excision, stereotactic radiosurgery, endovascular embolization, or combination. With bAVM embolization, complete angiographic obliteration ranges from 12.5 to 51%, and higher total occlusion rate is seen in SM grades I to III, ranging from 96 to 100%. Methods: In this paper, we illustrate the use of 3D rotational angiography and dynamic (live) 3D roadmap functions in endovascular treatment of bAVM. A single dynamic 3D roadmap or two dynamic 3D roadmaps obtained help tremendously in navigation of microcatheters and wires along the parent artery and bAVM feeders. Results: This method eliminates the need for repeated 2D angiograms and roadmaps for new working projections every time the C-arm position is changed for cannulation of different feeders, thereby reducing radiation dose. No instances of misalignment error, vascular perforation, or thromboembolic phenomena were observed in the 21 embolization cases performed within the previous 2 years while utilizing this feature. Conclusion: The dynamic 3D roadmap is an extremely useful tool for multiple-feeder cannulation, by reducing the use of multiple 2D angiograms, providing intraprocedural live and adjustable 3D roadmap for better mental orientation to angioarchitecture of the bAVM, which further aids in the overall complete angiographic obliteration rate of bAVM in a single session especially in multiplug embolization technique. [ABSTRACT FROM AUTHOR]

Objectives: Angioarchitectural analysis of brain arteriovenous malformations (BAVMs) is qualitative and subject to interpretation. This study quantified the morphology of and signal changes in the nidal and perinidal areas by using MR radiomics and compared the performance of MR radiomics and angioarchitectural analysis in detecting epileptic BAVMs. Materials and methods: From 2010 to 2020, a total of 111 patients with supratentorial BAVMs were retrospectively included and grouped in accordance with the initial presentation of seizure. Patients' angiograms and MR imaging results were analyzed to determine the corresponding angioarchitecture. The BAVM nidus was contoured on time-of-flight MR angiography images. The perinidal brain parenchyma was contoured on T2-weighted images, followed by radiomic analysis. Logistic regression analysis was performed to determine the independent risk factors for seizure. ROC curve analysis, decision curve analysis (DCA), and calibration curve were performed to compare the performance of angioarchitecture-based and radiomics-based models in diagnosing epileptic BAVMs. Results: In multivariate analyses, low sphericity (OR: 2012.07, p =.04) and angiogenesis (OR: 5.30, p =.01) were independently associated with a high risk of seizure after adjustment for age, sex, temporal location, and nidal volume. The AUC for the angioarchitecture-based, MR radiomics-based, and combined models was 0.672, 0.817, and 0.794, respectively. DCA confirmed the clinical utility of the MR radiomics-based and combined models. Conclusions: Low nidal sphericity and angiogenesis were associated with high seizure risk in patients with BAVMs. MR radiomics-derived tools may be used for noninvasive and objective measurement for evaluating the risk of seizure due to BAVM. Clinical relevance statement: Low nidal sphericity was associated with high seizure risk in patients with brain arteriovenous malformation and MR radiomics may be used as a noninvasive and objective measurement method for evaluating seizure risk in patients with brain arteriovenous malformation. Key Points: • Low nidal sphericity was associated with high seizure risk in patients with brain arteriovenous malformation. • The performance of MR radiomics in detecting epileptic brain arteriovenous malformations was more satisfactory than that of angioarchitectural analysis. • MR radiomics may be used as a noninvasive and objective measurement method for evaluating seizure risk in patients with brain arteriovenous malformation. [ABSTRACT FROM AUTHOR]

Copyright of China Journal of Oral & Maxillofacial Surgery is the property of Shanghai Jiao Tong University, College of Stomatology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arquivos de Ciências da Saúde da UNIPAR is the property of Associacao Paranaense de Ensino e Cultura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pulmonary arteriovenous malformations (PAVMs) are abnormal vascular connections between pulmonary arteries and veins, often associated with hereditary hemorrhagic telangiectasia (HHT). Most PAVMs are asymptomatic, but life-threatening complications like pulmonary hemorrhage, brain abscesses, and paradoxical emboli can emerge, so prompt diagnosis and treatment are crucial. We report a case of sudden pediatric death in a two-year-old female with no past medical history. Initial vomiting and fast deterioration resulted in a sudden cardiac arrest. The postmortem examination found histological evidence of consistent, extensive lung damage. The absence of the characteristic symptoms made for some challenges when it came to diagnosis, showing precisely that in early life, you could well have many difficulties in catching PAVMs. This case highlights the need to take PAVMs into account as a potential cause of sudden death, particularly when there are no conspicuous symptoms. Awareness among forensic pathologists and consideration of genetic analysis for HHT in such cases is crucial for accurate diagnosis and management.

Background: Brain Arteriovenous Malformations (AVMs) located in proximity to eloquent brain regions are associated with poor surgical outcomes, which may be due to higher rates of postoperative neurological deterioration. Current treatment protocols include stereotactic radiosurgery, transarterial embolization, and surgical resection under general anesthesia. Awake Craniotomy (AC) allows intraoperative mapping of eloquent areas to improve post-operative neurologic outcomes. Objectives: We reviewed the current literature reporting surgical outcomes and assessed the feasibility of AC for AVM resection. Methods: The PRISMA guidelines were utilized as a template for the review. Three databases including PubMed, Scopus, and Cochrane Library were searched using a predefined search strategy. After removing duplicates and screening, full texts were analyzed. Outcomes including the extent of resection, intra-operative and post-operative complications, and long-term neurologic outcomes were assessed. Results: 12 studies were included with a total of 122 AVM cases. Spetzler–Martin grading was used for the classification of the AVMs. The asleep–awake–asleep protocol was most commonly used for AC. Complete resection was achieved in all cases except 5. Intraoperative complications included seizures (n = 2) and bleeding (n = 4). Short-term post-operative complications included hemorrhage (n = 3), neurologic dysfunctions including paresis (n = 3), hemiplegia (n = 10), dysphasia/aphasia (n = 6), cranial nerve dysfunction (n = 3), and pulmonary embolism (n = 1). Almost all neurological deficits after surgery gradually improved on subsequent follow-ups. Conclusion: AVMs may shift the anatomical location of eloquent brain areas which may be mapped during AC. All studies recommended AC for the resection of AVMs in close proximity to eloquent areas as mapping during AC identifies the eloquent cortex thus promoting careful tissue handling which may preserve neurologic function and/or predict the postoperative functional status of the patients We, therefore, conclude that AC is a viable modality for AVMs resection near eloquent language and motor areas.

Abstract It is not common to encounter arteriovenous malformations (AVMs) during total hip arthroplasty (THA). We report the present case to draw attention to the possibility of an AVM during the direct anterior approach (DAA) for THA, which, if not borne in mind, may lead to the myriad of complications related to excessive bleeding. An 81-year-old female presented to the emergency department with a left femoral neck fracture. She elected to undergo a THA via the DAA. Abnormal appearing blood vessels were present near the ascending circumflex branches, which provided difficulty in achieving hemostasis. Excessive blood loss was noted, and the patient received one unit of packed red blood cells during the operation. Hemoglobin and hematocrit dropped in the days following surgery, requiring several additional transfusions of blood products. When the patient complained of progressive left leg swelling on postoperative day 3, a computed tomography revealed large hematomas within the left adductors and the left iliopsoas muscle. Active extravasation was identified arising from a branch of the left profunda femoral artery, as well as an arteriovenous fistula (AVF) in this area. Bleeding was controlled by selective endovascular coil embolization. As of current knowledge, this is the first reported intraoperative discovery of congenital arteriovenous malformation (AVM) with subsequent development of postoperative arteriovenous fistula and associated symptomatic hematomas in the setting of THA using the DAA. Early recognition and intervention of vascular malformations is essential in preventing potential limb- or life-threatening surgical complication.

Abstract Background Episodic growth due to microvascular proliferations (MVP) has been reported in congenital arteriovenous malformations (AVM), which are normally quiescent lesions composed of mature malformed vessels. Since AVM also may worsen under conditions of hormonal dysregulation, we hypothesized that hormonal influences may stimulate this process of vasoproliferative growth through potential interactions with hormone receptors (HR). Methods 13 Cases of AVM tissue with histologically documented vasoproliferative growth were analyzed quantitatively for the presence and tissue localization of estrogen receptor (ER), progesterone receptor (PGR), growth hormone receptor (GHR) and follicle-stimulating hormone receptor (FSHR) in relation to resident cells of interest (endothelial cells (EC), smooth muscle cells (SMC) and mast cells (MC)) by applying multiplex immunohistochemistry (IHC) staining. Expression patterns in lesions with MVP and mature vessels were quantified and compared. Available fresh frozen tissues of 3 AVM samples were used to confirm the presence of HR using Reverse-Transcriptase quantitative Polymerase Chain Reaction (RT-qPCR). Results All four HR studied were expressed in all cases within EC and SMC in areas of MVP and mature vessels, but not in normal skin tissue. ER, GHR, and FSHR showed more expression in EC of MVP and in SMC of mature vessels. RT-qPCR confirmed presence of all 4 HR in both areas. Conclusion Expression of ER, PGR, GHR, and FSHR in vasoproliferative areas of congenital AVM could explain onset of sudden symptomatic growth, as has observed in a subpopulation of patients. These findings may have implications for eventual anti-hormonal targeted therapy in the lesions involved.

Endoglin (ENG) mutation causes type 1 hereditary hemorrhagic telangiectasia (HHT1). HHT1 patients have arteriovenous malformations (AVMs) in multiple organs, including the brain. In mice, Eng deletion induced by R26RCreER or SM22αCre leads to AVM development in the brain and other organs. We hypothesized that an increase in Eng- negative ECs will enhance AVM severity. To increase EC Eng deletion, we used a codon-improved cre (icre), which is more potent in recombination of the floxed alleles than the wild-type (WT) cre. R26RCreER;Engf/f mice that have a Rosa promoter driving and tamoxifen (TM)-inducible WT cre expression globally, and PdgfbiCreER;Engf/f mice that have a Pdgfb promoter driving and TM-inducible icre expression in ECs were treated with three intra-peritoneal injections of TM (2.5 mg/25 g of body weight) to delete Eng globally or in the ECs. AAV-VEGF was stereotactically injected into the brain to induce brain focal angiogenesis and brain AVM. We found that icre caused more Eng deletion in the brain, indicated by a lower level of Eng proteins (p < 0.001) and fewer Eng-positive ECs (p = 0.01) than mice with WT cre. Mice with icre-mediated Eng deletion have more abnormal vessels (p = 0.02), CD68+ macrophages (p = 0.002), and hemorrhage (p = 0.04) and less vascular pericyte and smooth muscle coverage than mice with WT cre. In addition, arteriovenous shunts were detected in the intestines of icre mice, a phenotype that has not been detected in WT cre mice before. RNA-seq analysis showed that 8 out of the 10 top upregulated pathways identified by gene ontology (GO) analysis are related to inflammation. Therefore, the increase in Eng deletion in ECs exacerbates AVM severity, which is associated with enhanced inflammation. Strategies that can reduce Eng-negative ECs could be used to develop new therapies to reduce AVM severity for HHT1 patients.

The formation of vascular networks consisting of arteries, capillaries, and veins is vital in embryogenesis. It is also crucial in adulthood for the formation of a functional vasculature. Cerebral arteriovenous malformations (CAVMs) are linked with a remarkable risk of intracerebral hemorrhage because arterial blood is directly shunted into the veins before the arterial blood pressure is dissipated. The underlying mechanisms responsible for arteriovenous malformation (AVM) growth, progression, and rupture are not fully known, yet the critical role of inflammation in AVM pathogenesis has been noted. The proinflammatory cytokines are upregulated in CAVM, which stimulates overexpression of cell adhesion molecules in endothelial cells (ECs), leading to improved leukocyte recruitment. It is well‐known that metalloproteinase‐9 secretion by leukocytes disrupts CAVM walls resulting in rupture. Moreover, inflammation alters the angioarchitecture of CAVMs by upregulating angiogenic factors impacting the apoptosis, migration, and proliferation of ECs. A better understanding of the molecular signature of CAVM might allow us to identify biomarkers predicting this complication, acting as a goal for further investigations that may be potentially targeted in gene therapy. The present review is focused on the numerous studies conducted on the molecular signature of CAVM and the associated hemorrhage. The association of numerous molecular signatures with a higher risk of CAVM rupture is shown through inducing proinflammatory mediators, as well as growth factors signaling, Ras‐mitogen‐activated protein kinase‐extracellular signal‐regulated kinase, and NOTCH pathways, which are accompanied by cellular level inflammation and endothelial alterations resulting in vascular wall instability. According to the studies, it is assumed that matrix metalloproteinase, interleukin‐6, and vascular endothelial growth factor are the biomarkers most associated with CAVM and the rate of hemorrhage, as well as diagnostic methods, with respect to enhancing the patient‐specific risk estimation and improving treatment choices. [ABSTRACT FROM AUTHOR]

Arterial spin labeling (ASL) is a magnetic resonance perfusion technique that allows for quantification of cerebral blood flow (CBF) without the use of contrast or radiation. Several applications of ASL have been described in diagnosis of strokes and stroke mimics, intracranial tumors, and other conditions. Various vascular anomalies exhibit specific CBF patterns that correlate with different signal intensities on ASL. In this case-based review, we demonstrate the utility of ASL in diagnosis and surveillance of vascular anomalies in the intracranial compartment. [ABSTRACT FROM AUTHOR]