Angiographic Features of Meningiomas Predicting Extent of Preoperative Embolization.

BACKGROUND AND OBJECTIVES: Preoperative embolization is used as an endovascular adjunct to surgical resection of meningiomas. However, there is no standardized system to assess the efficacy or extent of embolization during the embolization procedure. We sought to establish a purely angiographic grading system to facilitate consistent reporting of the outcome of meningioma embolization and to characterize the anatomic and other features of meningiomas that predict the degree of devascularization achieved through preoperative embolization. METHODS: We identified patients with meningiomas who underwent preoperative cerebral angiography and subsequent resection between 2015 and 2021. Demographic, clinical, and imaging data were collected in a research registry. We defined an angiographic devascularization grading scale as follows: grade 0 for no embolization, 1 for partial embolization, 2 for majority embolization, 3 for complete external carotid artery embolization, and 4 for complete embolization. RESULTS: Eighty consecutive patients were included, 60 of whom underwent preoperative tumor embolization (20 underwent angiography with an intention to treat but ultimately not embolization). Embolized tumors were larger (59.0 vs 35.9 cc; P = .03). Gross total resection, length of stay, and complication rates did not differ among groups. The distribution of arterial feeders differed significantly across tumors in a location-specific manner. Both the tumor location and the identity of arterial feeders were predictive of the extent of embolization. Anterior midline meningiomas were associated with internal carotid (ophthalmic, ethmoidal) supply and lower devascularization grades (P = .03). Tumors fed by meningeal feeders (convexity, falcine, lateral sphenoid wing) were associated with higher devascularization grades (P < .01). The procedural complication rate for tumor embolization was 2.5%. CONCLUSION: Angiographic outcomes can be graded to indicate the extent of tumor embolization. This system may facilitate consistency of reported angiographic results. In addition, arterial feeders vary in a manner predicted by tumor location, and these patterns correlate with typical degrees of devascularization achieved in those tumor locations.

Vein of Galen Malformations.

Significant efforts have been made over the last few decades to improve the diagnosis and management of patients with vein of Galen malformations (VOGMs). The mainstays of treatment remain focused on primary endovascular management by staged transarterial embolizations with adjunctive use of transvenous embolization, medical therapy, and neurosurgical intervention for symptom control in select patients. Innovation in endovascular technology and techniques as well as promising new genomic research elucidating potential therapeutic targets hold significant promise for the future of VOGM treatment.

Most Promising Approaches to Improve Brain AVM Management: ARISE I Consensus Recommendations.

Brain arteriovenous malformations (bAVMs) are complex, and rare arteriovenous shunts that present with a wide range of signs and symptoms, with intracerebral hemorrhage being the most severe. Despite prior societal position statements, there is no consensus on the management of these lesions. ARISE (Aneurysm/bAVM/cSDH Roundtable Discussion With Industry and Stroke Experts) was convened to discuss evidence-based approaches and enhance our understanding of these complex lesions. ARISE identified the need to develop scales to predict the risk of rupture of bAVMs, and the use of common data elements to perform prospective registries and clinical studies. Additionally, the group underscored the need for comprehensive patient management with specialized centers with expertise in cranial and spinal microsurgery, neurological endovascular surgery, and stereotactic radiosurgery. The collection of prospective multicenter data and gross specimens was deemed essential for improving bAVM characterization, genetic evaluation, and phenotyping. Finally, bAVMs should be managed within a multidisciplinary framework, with clinical studies and research conducted collaboratively across multiple centers, harnessing the collective expertise and centralization of resources.

Use of a mini balloon microcatheter to facilitate penetration of fine vascular networks and curative embolization in vein of Galen malformations.

Background Patients with vein of Galen malformations (VOGMs) can develop fine angiogenic networks with fistulous connections to the precursor of the vein of Galen. In these cases, transarterial embolization (TAE) with liquid embolic agents (LEAs) is challenging due to reflux in the pedicle leading to the network, causing poor penetration. Transvenous approaches carry a risk of hemorrhage from pathologic vasculature. Dual-lumen balloon microcatheters like the Scepter Mini (Microvention, Aliso Viejo, CA) improve distal pedicle access, preventing reflux.Objective Here, we report on the use of the Scepter Mini for TAE of angiogenic VOGM.Methods A single-institution retrospective chart review identified all VOGMs treated with Scepter Mini microcatheters. Clinical data, angioarchitecture, and technical parameters were reviewed.Results 17 Scepter Mini catheters were used in 12 embolization procedures of 7 patients with VOGM at a median age of 2.1 years. Patients presented with hydrocephalus (100%) and gross motor and speech delays (57.1%). Networks developed extra-axially into the subependymal zone fed by posterior choroidal, posterior cerebral, and thalamoperforator arteries. Posterior choroidal branches (n=7/17, 41.2%) were most frequently catheterized to achieve distal access to the network. Embolization with Onyx-18 and significant network penetration occurred in 17/17 uses. Near tip entrapment with LEA cast displacement occurred in 1/17 uses. Another patient experienced postprocedural intraventricular hemorrhage requiring a third ventriculostomy without permanent neurologic deficit.Conclusion The Scepter Mini provided excellent distal access with penetration to the fistula and extra-axial network reduction with few complications. The Scepter Mini provides a means for successful treatment of technically challenging angiogenic VOGM.

Transvenous balloon-assisted approach to anterior fossa dural arteriovenous fistula using retrograde pressure cooker technique.

Endovascular embolization is the first-line therapy for dural arteriovenous fistulas (dAVFs). Transarterial embolization (TAE) may be limited by poor anatomical access. Transvenous embolization avoids this, but carries a risk of hemorrhage, venous redirection, and neurologic deterioration. Dual-lumen balloon microcatheters like the Scepter Mini (Microvention, Aliso Viejo, CA, USA) provide flow arrest and prevent reflux during TAE with liquid embolic agents (LEAs), but use in the distensible veins may be challenging. In this video, we use a Scepter Mini in a transvenous approach to a Cognard type IV anterior ethmoidal dAVF as a safe alternative to surgery, transvenous pressure cooker, and trans-ophthalmic TAE (video 1). The Scepter Mini was navigated transvenously to the anterior superior sagittal sinus. LEA was injected with excellent penetration to the venous pouch and further penetration into the network of tortuous feeders. No neurologic complications were experienced, and follow-up angiogram 9 months later demonstrated cure of the dAVF. Video 2 describes procedural considerations in transvenous approaches, steps of the procedure, and includes references1-10 which are relevant to this topic.neurintsurg;jnis-2023-020530v1/V1F1V1Video 1 neurintsurg;jnis-2023-020530v1/V2F2V2Video 2 .

Genetic dysregulation of an endothelial Ras signaling network in vein of Galen malformations.

To elucidate the pathogenesis of vein of Galen malformations (VOGMs), the most common and severe congenital brain arteriovenous malformation, we performed an integrated analysis of 310 VOGM proband-family exomes and 336,326 human cerebrovasculature single-cell transcriptomes. We found the Ras suppressor p120 RasGAP ( RASA1 ) harbored a genome-wide significant burden of loss-of-function de novo variants (p=4.79×10 -7 ). Rare, damaging transmitted variants were enriched in Ephrin receptor-B4 ( EPHB4 ) (p=1.22×10 -5 ), which cooperates with p120 RasGAP to limit Ras activation. Other probands had pathogenic variants in ACVRL1 , NOTCH1 , ITGB1 , and PTPN11 . ACVRL1 variants were also identified in a multi-generational VOGM pedigree. Integrative genomics defined developing endothelial cells as a key spatio-temporal locus of VOGM pathophysiology. Mice expressing a VOGM-specific EPHB4 kinase-domain missense variant exhibited constitutive endothelial Ras/ERK/MAPK activation and impaired hierarchical development of angiogenesis-regulated arterial-capillary-venous networks, but only when carrying a "second-hit" allele. These results illuminate human arterio-venous development and VOGM pathobiology and have clinical implications.

New concept in neurovascular navigation: technical description and preclinical experience with the Bendit 17 and Bendit 21 microcatheters in a rabbit aneurysm model.

BACKGROUND: Endovascular treatment of intracranial vascular diseases, such as aneurysms, is often challenged by unfavorable vascular anatomy. The Bendit Steerable Microcatheter (Bendit Technologies, Tel Aviv, Israel) has bending and torqueing capabilities designed to improve navigation and stability during device delivery, with or without a guidewire. We describe our preclinical experience with the Bendit 17 and Bendit 21 microcatheters in a rabbit aneurysm model. METHODS: Bifurcation and side wall aneurysms were created surgically in six New Zealand rabbits. We attempted to navigate Bendit devices through the vasculature and enter the aneurysms without a guidewire. Various positions within the aneurysm were selectively explored. Angiographic imaging was used to visualize catheterization, navigation, vascular manipulations, and placement of coils, stents, and intrasaccular devices. RESULTS: We successfully navigated the Bendit microcatheters to all aneurysms without a guidewire. We successfully recanalized a nearly occluded carotid artery and navigated the Bendit through a braided stent. In contrast, we were unable to navigate a comparator device with a guidewire as effectively as the Bendit. Coils were introduced at different locations within the aneurysm and could be pushed, pulled, and repositioned with the Bendit tip. Finally, we used the Bendit to deliver intrasaccular devices designed for terminal aneurysms to treat side wall aneurysms. CONCLUSIONS: Bendit's bending and torqueing abilities, combined with its stability in the bent position, enable quick navigation and optimal deployment of devices. Clinical studies are necessary to determine whether these navigation advantages lead to more efficient treatment of intracranial and peripheral aneurysms.

Percutaneous sclerotherapy of microcystic lymphatic malformations: the use of an innovative gravity-dependent technique.

BACKGROUND: In the last few decades there has been development of innovative therapies for the treatment of craniofacial lymphatic malformations. Percutaneous sclerotherapy has demonstrated efficacy in the management of macrocystic lymphatic lesions, but it is less suitable for microcystic lesions given their size. The gravity-dependent technique is a novel augmentation of standard percutaneous sclerotherapy: the technique enables a sclerosing agent to permeate the small microchannels seen in microcystic lesions that would otherwise be difficult to treat. METHODS: Between 2005 and 2021, 124 patients with microcystic or mixed lymphatic malformations were treated using a novel gravity-dependent sclerotherapy technique. Bleomycin at a maximum dose of 15 IU per session was used as the main sclerosing agent. Fluoroscopy and ultrasound were used to ensure proper positioning of the catheter prior to injecting the sclerosing agent. The response to treatment was assessed clinically and with cross-sectional imaging. RESULTS: Nearly all cases showed significant improvement after the gravity-dependent technique. There have been no permanent complications from sclerotherapy treatment. There was a mild transient adverse effect from bleomycin in one case of erythema and tenderness that lasted several weeks then ameliorated. CONCLUSIONS: The gravity-dependent sclerotherapy technique is a suitable treatment option for microcystic lymphatic malformations.

Infantile dural sinus malformation: curative embolization in two stages with the Scepter mini balloon microcatheter.

Endovascular embolization is the mainstay for treatment of infantile dural sinus malformations.1 2 Distal access and flow control are limiting factors in controlled embolization.3-6 The Scepter mini catheter (Microvention, Aliso Viejo, California, USA) is a low-profile, dual-lumen balloon microcatheter designed to provide navigability in small-caliber, tortuous intracranial vessels. In this technical video, we demonstrate the staged embolization of a dural sinus malformation with multiple arteriovenous fistulae using the Scepter mini catheter (video 1). In the newborn patient, embolizations were performed through the parietal branches of the left and right middle meningeal arteries. The catheter easily navigated into the small feeding arteries. No neurological complications occurred due to the procedures. Post-embolization injections demonstrated significant flow reduction into the malformation. Three-month follow-up angiography illustrated resolution of the previously dilated left transverse sinus. Complete obliteration of the dural sinus malformation was achieved in the newborn patient. neurintsurg;15/1/97/V1F1V1Video 1Curative embolization in two stages with the Scepter mini balloon microcatheter. ΑP, anteroposterior; CCA, common carotid artery.

Evolution of transvenous embolization in vein of Galen malformation: case series and review of the literature.

BACKGROUND: Treatment of vein of Galen malformations (VOGMs) has improved greatly since the inception of endovascular treatment. Transvenous embolization (TVE) is an attractive option to achieve complete obliteration. OBJECTIVE: To review the literature on TVE of VOGM and then analyze our practice's unique experience and evolving treatment strategies over 30 years. METHODS: A retrospective review of our clinical database for patients with the diagnosis of VOGM treated between January 2004 and August 2021 was performed. A literature review of 49 relevant articles was also carried out. RESULTS: TVE in VOGM has evolved with initial introduction as a transtorcular (TT) approach, which then lost favor to transarterial embolization (TAE). TAE has been considered the more favorable approach in most high-volume centers. In more recent times, the transvenous embolization (TVE) approach has been revisited as a last treatment to achieve a cure after a series of TAE treatments. We presently favor beginning treatment with staged TAE to reduce flow to the lesion and, importantly, shrink the draining vein. This then allows for the performance of TVE with the Chapot pressure cooker technique (CPCT) with coils and liquid embolic embolization. CONCLUSIONS: TT TVE itself carries a high degree of risk and is most highly associated with long-term morbidities and mortality. Traditional transfemoral/transjugular TVE approaches are safe and effective in simple fistulas with a small venous pouch; however, we believe that the CPCT is the safest technique as a last-stage treatment for its security in avoiding reflux and obtaining occlusion of the small perforators.

Clinical experience with the Bendit steerable microcatheter: a new paradigm for endovascular treatment.

BACKGROUND: Vessel tortuosity poses a challenge during endovascular treatment of neurovascular lesions. Bendit Technologies (Petah Tikva, Israel) has developed flexible, steerable microcatheters designed with unique bending and torquing capabilities. OBJECTIVE: To describe our first-in-human trial of Bendit21. METHODS: Bendit21 was used in our exploratory, prospective, multicenter, open-label, single-arm clinical study, and in two compassionate use cases. Procedures were conducted at four centers in Austria, Germany, Israel, and the United States between May 2021 and March 2022, in patients with neurovascular conditions. The primary endpoints were device-related safety events, successful navigation through the neurovasculature, and, when intended, successful delivery of contrast or therapy. RESULTS: Two patients with giant aneurysms were treated successfully under compassionate use approval. The clinical study included 25 patients (mean age: 63.4±11.8 years; 32.0% female). Fourteen patients (56.0%) had aneurysms, two had arteriovenous malformations/fistulas (8.0%), one had a stroke (4.0%), four (16.0%) had intracranial stenosis, and four (16.0%) had other conditions. Bendit21 was used without a guidewire in 12/25 (48.0%) procedures. Bendit21 was successfully navigated through the vasculature without delays or spasms in all cases (100%). Contrast was delivered as intended in 7/7 (100%) cases. Therapeutic devices were delivered successfully with Bendit as intended in 14/18 (77.8%) cases; four deficiencies occurred in three patients with aneurysms, in whom delivery of coils, an intrasaccular device, or a flow diverter was attempted. There were no device-related safety events or mortalities. CONCLUSIONS: Our initial clinical experience with the Bendit21 microcatheter demonstrates its usefulness in achieving technical success in patients with challenging neurovascular conditions.

Transvenous embolization of vein of galen aneurysmal malformations with coils as a final procedure for cure: A single-institution experience of 18 years.

INTRODUCTION: Staged, transarterial embolization (TAE) is currently considered the gold standard for the treatment of vein of Galen aneurysmal malformation (VGAM); however, as transarterial access becomes restricted, further staged TAE may become ineffective or carry an increased risk of hemorrhagic or ischemic stroke when attempting complete obliteration. OBJECTIVE: To describe the first consecutive, retrospective series of VGAM treated with transvenous embolization (TVE) with coils alone, as the final treatment in staged endovascular therapy, at a single institution between January 2004 and September 2021. RESULTS: A total of 10 patients with a median age of 5.5 (IQR: 9.25) years were treated with coiling TVE. Patients were treated with a median number of 5 (IQR: 2.75) TAEs prior to the final TVE treatment. Complete or near-complete immediate angiographic obliteration was achieved in eight patients. Immediate post-procedural (within 48 h) hemorrhagic complications were noted in two patients (20%), one of whom passed away while the second suffered from hemiparesis. Stereotactic radiosurgery was performed in two patients with incomplete obliteration after TVE. The median follow-up time after TVE was 17 (IQR: 9) months. At long-term follow up (17 months) for the remaining nine patients, all VGAMs were completely obliterated. Long-term clinical deterioration compared to pre-TVE was noticed in one case. CONCLUSION: Transvenous coil embolization is a technically feasible but risky option, as a final-stage treatment for cure of VGAMs with restricted trans-arterial access. Although TVE with coils remains an effective therapeutic modality, we recommend continuing investigation of safer TVE techniques to achieve cure.

Middle Meningeal Artery Embolization for Chronic Subdural Hematoma Using N-Butyl Cyanoacrylate With D5W Push Technique.

BACKGROUND: Middle meningeal artery (MMA) embolization has been recognized as a promising treatment for patients with subdural hematoma (SDH). OBJECTIVE: To present the technical feasibility and efficacy of n-butyl cyanoacrylate (n-BCA) embolization in the largest consecutive cohort to date. METHODS: We retrospectively reviewed our consecutive cases of recurrent SDH treated with MMA embolization using diluted n-BCA with the "sugar rush" technique. In brief, a 2.1-Fr microcatheter was used to selectively catheterize the frontal and posterior branches of the MMA. 5% dextrose in water (D5W) was injected through an intermediate catheter while injecting n-BCA through the microcatheter. Complete obliteration of MMA and lack of SDH recurrence in a 3-6 months follow-up computed tomography scan were defined as efficacy outcomes. Cranial nerve palsy, vision loss, transient neurological deficit, and stroke were defined as safety outcomes. RESULTS: A total of 61 patients were identified with a mean (±standard deviation) age of 62.5 ± 9 years. In 6 patients (10%), coil embolization of the origin of the frontal or posterior branch was performed because super-selective catheterization of the branch was unsuccessful because of tortuous anatomy. Complete obliteration of frontal and posterior branches was achieved in 100% of the cases. Recurrent SDH was seen in 3 patients (5%). No incidence of cranial nerve palsy, vision loss, or stroke occurred. One patient suffered a transient neurological deficit. CONCLUSION: MMA embolization using diluted n-BCA with concomitant D5W injection is associated with a high degree of distal penetration and complete branch occlusion and minimal risk of cranial nerve palsy or other thromboembolic complications.

De novo brain AVM following radiotherapy for cerebral cavernous malformation in a child: A 15-year clinical course.

Multiple de novo brain arteriovenous malformations (bAVM) have been reported in the literature, raising questions about the contended purely congenital nature of these lesions. We present the 15-year course of a pediatric patient, who initially presented at age 5 with a thalamic cavernous malformation and was treated with radiosurgery, and then subsequently developed a thalamic de novo bAVM immediately adjacent to the initial lesion location, discovered 2 years later. Treatment of the bAVM entailed two transarterial embolizations and one radiosurgery session which ultimately led to complete angiographic resolution. Finally, this patient's course was complicated by intraparenchymal hemorrhage and acute obstructive hydrocephalus, and further imaging revealed two newly formed cavernous malformations, also associated with the initial lesion's location, that have remained stable since their formation. This case likely represents the second-hit model for the formation of vascular malformations, as sparsely supported by the current literature. According to this, genetically aberrant, yet quiescent, brain areas might promote the de novo formation of vascular malformations after brain injury, including radiation.

Combined Treatment of High-Flow Scalp Arteriovenous Malformations.

INTRODUCTION: Appropriate treatment of scalp arteriovenous malformations (SAVMs) remains largely unclear given the rarity of reported cases. This single-institution case series presents consecutive patients with extracranial SAVMs and long-term follow up.The primary aim of this study was to review treatment decisions, evaluate clinical outcomes, and compare our experience to available literature in order to better understand SAVMs and improve future outcomes. MATERIALS AND METHODS: A retrospective review of consecutive patients with extracranial SAVMs between January 2015 and December 2019 was performed. Treatment factors of interest included embolization method, embolic agents, and decision to proceed with surgical resection. Relevant clinical outcomes included recurrence rates, cure rates, and complications. RESULTS: Seven patients were included in the present series. Satisfactory outcomes were ultimately achieved for all 7 patients using embolization with or without combined surgical resection. Embolizations performed in combination with resection were curative in 4 of 4 cases (100%). Embolizations performed without resection were curative in 0 of 4 cases (0%), satisfactory in 2 of 4 cases (50%), and unsatisfactory in 2 of 4 cases (50%). DISCUSSION: All SAVM patients in this series were treated satisfactorily using embolization with or without operative resection. This study strongly suggests that embolization combined with surgical resection during the same admission yields the best treatment outcomes for SAVMs, specifically demonstrating lower rates of recurrence and embolization-related complications. Decisions on whether or not to proceed with resection should be made by the interventional radiologist, the plastic surgeon, and the patient together.

Initial experience with the Scepter Mini catheter for the embolization of vascular malformations in the pediatric population.

BACKGROUND: Achieving distal access and flow control are of significant importance for the treatment of intracerebral arteriovenous shunting lesions. The Scepter Mini catheter is a low-profile, dual-lumen balloon catheter, designed to provide navigability in small-caliber, tortuous intracranial vessels. OBJECTIVE: To describe the initial experience of the Scepter Mini catheter in the treatment of pediatric arteriovenous malformations and fistulas. METHODS: A single-institution, retrospective chart review identified all consecutive uses of the Scepter Mini catheter for endovascular embolization of vascular malformations in the pediatric population. RESULTS: Three different arterial pedicles were embolized with the Scepter Mini catheter in two different patients. One patient was diagnosed with a vein of Galen malformation that had undergone multiple treatments and the other with a torcular dural arteriovenous fistula. All cases encompassed quite challenging tortuosity of small-caliber feeders which prevented the use of another microcatheter. The Scepter Mini catheter navigated into feeding arteries of diameters 0.65, 1.9, and 1.25 mm, and its balloon was inflated to achieve excellent blood flow control. Total obliteration (100%) of the shunting lesion was achieved in both cases. No reflux, pedicle rupture or other untoward effects were observed. Both patients had an uneventful recovery. CONCLUSION: The Scepter Mini catheter afforded fast and safe distal access, flow control, and treatment of arteriovenous malformations in this initial pediatric cohort. The catheter's low profile and easy navigability should support its use in tortuous and small arterial feeders, especially in the pediatric population.

Transvenous embolization of vein of galen aneurysmal malformations using the "Chapot pressure cooker" technique.

METHODS: Two patients, one 5-year-old and one 7-year-old, both presented with congestive heart failure in the newborn period and were subsequently treated in the newborn period with multiple, staged TAEs with n-BCA for choroidal VGAMs. RESULTS: We achieved progressive reduction in shunting and flow but were unable to accomplish complete closure of the malformation: in both patients, a small residual with numerous perforators persisted. The decision was made to perform TVE using the CHPC. In this technique, a guiding catheter is placed transjugular into the straight sinus (SS). One or two detachable tip microcatheters are advanced to the origin of the SS. Another microcatheter is advanced and the tip placed between the distal marker and the detachment zone of the former. Coils and n-BCA are used to prevent reflux of Onyx. CONCLUSIONS: In this study, we recognized two important factors of traditional VGAM treatment that may cause interventionalists to consider the ChPC to treat VGAM: (1) without liquid embolic, deployed coils may not occlude the fistula entirely. (2) There is the concern of causing delayed bleeding should the arterial component of the fistula rupture. ChPC ameliorates these issues by offering complete closure of the fistula with liquid embolic material in TVE.

Middle Meningeal Artery Embolization of a Pediatric Patient With Progressive Chronic Subdural Hematoma.

BACKGROUND AND IMPORTANCE: Evidence suggests middle meningeal artery (MMA) embolization benefits adult patients with chronic subdural hematoma (CSDH) at high risk for recurrence or hemorrhagic complications. Yet, there has not been any report discussing MMA embolization in the pediatric population. Thus, we present a case of an infant with CSDH successfully managed with MMA embolization without surgical management. CLINICAL PRESENTATION: A 5-mo-old girl with idiopathic dilated cardiomyopathy underwent surgical implantation of a left ventricular assist device for a bridge to heart transplantation. This was complicated by left ventricular thrombus causing stroke. She was placed on dual antiplatelet antithrombotic therapy on top of bivalirudin infusion. She sustained a left middle cerebral artery infarction, but did not have neurological deficits. Subsequent computed tomography scans of the head showed a progressively enlarging asymptomatic CSDH, and the heart transplant was repeatedly postponed. The decision was made to proceed with MMA embolization at the age of 7 mo. Bilateral modified MMA embolization, using warmed, low-concentration n-butyl-cyanoacrylate (n-BCA) from distal microcatheter positioning, allowed the embolic material to close the distal MMA and subdural membranous vasculature. The patient underwent successful heart transplant and the CSDH improved significantly. She remained neurologically asymptomatic and had normal neurological development after the MMA embolization. CONCLUSION: MMA embolization may represent a safe and effective minimally invasive option for pediatric CSDH, especially for patients at high risk for surgery or hematoma recurrence.