medicina Case Report Case Study of a Complex Neurovascular Disorder: Choroidal Arteriovenous Malformation Corneliu Toader 1,2 , Razvan-Adrian Covache-Busuioc 1, *, Bogdan-Gabriel Bratu 1 , Luca Andrei Glavan 1 , Antonio Daniel Corlatescu 1 and Alexandru Vlad Ciurea 1,3 1 2 3 * Department of Neurosurgery, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; corneliu.toader@umfcd.ro (C.T.); bogdan.bratu@stud.umfcd.ro (B.-G.B.); luca-andrei.glavan0720@stud.umfcd.ro (L.A.G.); prof.avciurea@gmail.com (A.V.C.) Department of Vascular Neurosurgery, National Institute of Neurology and Neurovascular Diseases, 077160 Bucharest, Romania Neurosurgery Department, Sanador Clinical Hospital, 010991 Bucharest, Romania Correspondence: razvan-adrian.covache-busuioc0720@stud.umfcd.ro Abstract: This study conducts an in-depth analysis of the management of a complex arteriovenous malformation (AVM) in a 44-year-old individual, who initially manifested with acute left hemiparesis and progressively declined into a comatose state. Diagnostic neuroimaging identified a substantial right fronto-temporal intraparenchymal hematoma via a CT scan. Cerebral angiography further elucidated a choroidal AVM originating from the anterior choroidal artery, accompanied by intranidal aneurysms. The elected treatment strategy was the surgical excision of the AVM. The procedure achieved complete removal of the intracranial AVM, situated in a neurologically sensitive region, leading to notable neurological recovery. This study thoroughly explores and critically evaluates a wide spectrum of treatment approaches for intracranial arteriovenous malformations, including novel endovascular therapies. Despite extensive discourse on AVM in contemporary literature, this report is among the few documenting the treatment of a choroidal AVM via a microsurgical technique, and highlights various therapeutic options. Citation: Toader, C.; Covache-Busuioc, R.-A.; Bratu, B.-G.; Glavan, L.A.; Keywords: surgical treatment; 3D rotational DSA; 2D DSA; intraparenchymal hematoma; intranidal aneurysm; arteriovenous malformation; anterior choroidal artery Corlatescu, A.D.; Ciurea, A.V. Case Study of a Complex Neurovascular Disorder: Choroidal Arteriovenous Malformation. Medicina 2024, 60, 302. https://doi.org/10.3390/ medicina60020302 Academic Editor: Stefan Schob Received: 5 January 2024 Revised: 31 January 2024 Accepted: 5 February 2024 Published: 10 February 2024 Copyright: © 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). 1. Introduction Arteriovenous malformations (AVMs) are defined as aberrant connections between arteries and veins, bypassing the capillary system. They exhibit epidemiological incidences ranging from 1.12 to 1.42 per 100,000 person-years, with 38–68% of cases initially presenting as hemorrhages. The annual hemorrhage rate for untreated cerebral AVMs is estimated at 2.10–4.12%. Research has concentrated on identifying determinants that increase the likelihood of AVM rupture [1]. Meta-analytical studies have correlated heightened rupture risks with factors such as previous rupture events, deep cerebral location, and exclusive deep venous drainage. Gross and Du documented an overall annual hemorrhage risk of 3.0% in observed AVMs, delineating 2.2% for unruptured and 4.5% for previously ruptured AVMs. Furthermore, Stapf et al. identified an exceptionally high annual rupture rate of 35.5% in AVMs characterized by a triad of deep venous drainage, deep cerebral location, and a history of hemorrhage [2]. Peripheral arteriovenous malformations (AVMs) represent a prevalent clinical entity, which can be systematically categorized based on the anatomical classification proposed by Shen et al. in 2023. This classification delineates four primary regions: cephalic and cervical, truncal (comprising the thoracic, abdominal, and dorsal regions), upper extremities (including the shoulder, brachium, cubital area, antebrachium, and manus), and lower extremities (consisting of the gluteal area, femoral region, genicular area, popliteal fossa, Medicina 2024, 60, 302. https://doi.org/10.3390/medicina60020302 https://www.mdpi.com/journal/medicina Medicina 2024, 60, 302 2 of 9 crural region, and pedal region) [3]. Furthermore, arteriovenous shunts located intracranially and within the spinal axis that drain into spinal venous structures can precipitate hypertension in the spinal perimedullary venous plexus, subsequently affecting the spinal intramedullary veins [4]. In a unique case reported by Jiang et al. in 2023, a patient suffering from a supratentorial pial AVM manifested myelopathy, characterized by notable weakness predominantly in the upper extremities, with minimal lower limb involvement, emerging two months post initial symptom onset. Post-intervention, the patient exhibited significant amelioration in cervical rigidity, and regained the ability to elevate the upper limbs and to self-dress within a week. After a period of two months, there was a near-complete resolution of the upper limb weakness, although hyperreflexia persisted in both upper and lower extremities [5]. The lack of an intervening capillary network in AVMs results in direct exposure of venous structures to elevated arterial pressures, potentially leading to serious complications such as hemorrhage. This represents an important concern in the central nervous system (CNS), where intracranial hemorrhages due to AVM ruptures can result in significant morbidity or mortality. The diagnostic and therapeutic approaches for AVMs are complex, reflecting their varied clinical manifestations and impacts on patient health. AVMs are frequently identified during evaluations following acute cerebral hemorrhage or incidentally through imaging conducted for other neurological symptoms like seizures or headaches [6,7]. As outlined by Conger et al., the diagnosis necessitates an integrated strategy encompassing patient history, physical examination, and advanced imaging techniques, including computed tomography, magnetic resonance imaging, and catheter angiography. This comprehensive approach facilitates a thorough elucidation of the AVM’s anatomical and hemodynamic characteristics. Choroidal arteriovenous malformations, albeit infrequent, present distinct challenges due to their deep-seated location within the brain and proximity to crucial paraventricular structures [8,9]. These AVMs often exhibit recruitment of feeder vessels from both the anterior and posterior choroidal arteries [10,11]. The integration of microsurgical techniques into neurosurgical practices has facilitated the complete excision of these lesions, while preserving the integrity of adjacent critical structures. This surgical advancement has been highlighted through documented cases of successful removal of paraventricular or intraventricular AVMs [12]. In treating AVMs, the efficacy of individual therapeutic modalities is acknowledged, yet a multidisciplinary approach is frequently required to achieve optimal outcomes. Endovascular embolization, in particular, plays a versatile role as a preoperative or preradiosurgical step, and in certain cases, as a standalone curative procedure. Given that choroidal arteries traverse the lateral aspect of the ventricles, AVMs originating from these vessels pose greater challenges due to their deep location [13–15]. Surgical access to the anterior choroidal artery (AchA) and lateral posterior choroidal artery (LPchA) is intricate. Furthermore, AVMs situated superficially to the choroidal feeding arteries can impede surgical maneuvers. In such instances, the curative or preoperative embolization of the AchA may be advantageous, as elaborated in our research focused on endovascular AVM embolization through choroidal arteries, either as curative or adjunctive treatments [16]. We present a case involving a choroidal AVM, one of the most uncommon vascular anomalies, with limited literature available. Remarkably, our study achieved a complete resection of this AVM, leading to postoperative neurological improvement. 2. Case Presentation A 44-year-old patient was admitted to our clinic for sudden left hemiparesis MRC 1/5 occurring in the apparent health status 48 h prior to admission, followed by the deterioration of consciousness that become gradually worse, with the patient becoming comatose. She was admitted to our clinic with GCS = 7 points (eye response—2 points, verbal response—2 points, motor response—3 points), orotracheally intubated, and mechanically ventilated. Neurological examination on admission revealed a left hemiparesis, predomi- Medicina 2024, 60, x FOR PEER REVIEW Medicina 2024, 60, x FOR PEER REVIEW Medicina 2024, 60, 302 3 of 9 3 of 9 3 of 9 points, points, motor motor response—3 response—3 points), points), orotracheally orotracheally intubated, intubated, and and mechanically mechanically ventilated. ventilated. Neurological examination on admission revealed a left hemiparesis, predominantly Neurological examination on admission revealed a left hemiparesis, predominantly in in the the nantly region in the brachial region and comatose A brain non-contrast CT scana revealed brachial and state. A non-contrast CT brachial region and comatose comatose state. A brain brainstate. non-contrast CT scan scan revealed revealed a voluminous voluminous a voluminous right fronto-temporal intraparenchymal hematoma with panventricular right right fronto-temporal fronto-temporal intraparenchymal intraparenchymal hematoma hematoma with with panventricular panventricular infiltration, infiltration, signifisignifiinfiltration, significant mass effect on the right lateral ventricle, and 1.5 cm displacement cant mass effect on the right lateral ventricle, and 1.5 cm displacement of the midline. Othcant mass effect on the right lateral ventricle, and 1.5 CT cmappearance displacement ofseen the (Figure midline. Othof the normal midline.cerebroventricular Otherwise, normal cerebroventricular was 1). was erwise, CT appearance was seen (Figure 1). Angiography erwise, normal cerebroventricular CT appearance was seen (Figure 1). Angiography Angiography was performed through the selective injection of the internal carotid artery was performed through the injection of internal carotid artery bilaterally, right performed the selective selective of the the right exexbilaterally,through right external carotidinjection artery, and left internal vertebralcarotid artery. artery Right bilaterally, temporal arteriternal carotid artery, and left vertebral artery. Right temporal arteriovenous malformation ternal carotid artery, and left vertebral artery. Right temporal arteriovenous malformation ovenous malformation with arterial afferents from the right anterior choroidal artery and with arterial from right anterior choroidal artery and right-sided middle right-sided middle cerebral artery observed, Spetzler Martin III (Figure 2). Acerewith arterial afferents afferents from the the rightwas anterior choroidal artery andgrade right-sided middle cerebral artery was grade III 2). nidus nidus of approximately 2/1 cm inMartin size with several intranidal was also ob- 2/1 bral artery was observed, observed, Spetzler Spetzler Martin grade III (Figure (Figure 2). A Aaneurysms nidus of of approximately approximately 2/1 cm in size with several intranidal aneurysms was also observed (Figure 3). A single vein was served (Figure 3). A single vein was draining into the right cavernous sinus, through an cm in size with several intranidal aneurysms was also observed (Figure 3). A single vein was draining into right cavernous intermediate venous draining into the the rightsource. cavernous sinus, sinus, through through an an intermediate intermediate venous venous source. source. Figure Preoperative intraparenchymal Figure1. PreoperativeCT CTscan. scan.Axial Axialsection section(A) (A)highlights highlightsthe the intraparenchymalhematoma hematoma(red Figure 1.1.Preoperative CT scan. Axial section (A) highlights the intraparenchymal hematoma (red arrow); moreover, frontal frontal (B) and sagittal (C) sections depict the massive hematoma with panventric(red arrow); moreover, and sagittal (C) sections depict the massive hematoma with arrow); moreover, frontal (B) and(B) sagittal (C) sections depict the massive hematoma with panventricular implication too (red arrows). ular implication too (red arrows). panventricular implication too (red arrows). Figure 2. Preoperative 2D digital subtraction angiography. Profile (A) and frontal (B) 2D DSA Figure Preoperative 2D subtraction angiography. Profile Profile (A) (A) and and frontal (B) (B) 2D DSA DSA Figure2.2.the Preoperative 2D digital digital subtraction angiography. highlights right temporal arteriovenous malformation (red arrows), foundfrontal as well in 2D 2D DSA highlights the right temporal arteriovenous malformation (red arrows), found as well in 2D DSA highlights the(C). right temporalprofile arteriovenous (red arrows), found as well in 2D DSA reconstruction Moreover, 2D DSAmalformation (A) shows a slight dilatation of the anterior choroidal reconstruction (C). (A)shows showsaaslight slightdilatation dilatation the anterior choroidal reconstruction (C).Moreover, Moreover,profile profile 2D 2D DSA DSA (A) ofof the anterior choroidal artery (blue arrow). artery (blue arrow). artery (blue arrow). The selected treatment approach involved the surgical removal of the arteriovenous malformation (AVM) at the right anterior choroidal artery and the evacuation of a significant deep frontotemporal intraparenchymal hematoma on the right side. Postoperatively, the patient has a favorable evolution with notable neurological recovery. The patient regained consciousness, allowing for successful extubation. Medicina 2024,2024, 60, x60, FOR Medicina 302PEER REVIEW 4 of 94 of 9 Figure 3. Preoperative 3D DSA rotational angiography. The 3D reconstruction of rotational DSA (A) depicts the tridimensional topography of the arteriovenous malformation. In high-resolution image (B), multiple intranidal sacullar and fusiform aneurysms were found (blue arrows). The selected treatment approach involved the surgical removal of the arteriovenous malformation (AVM) at the right anterior choroidal artery and the evacuation of a significant deep frontotemporal hematoma on side. Postoperatively, the Figure 3. Preoperative intraparenchymal 3D DSA rotational angiography. Thethe 3D right reconstruction of rotational DSA Figure 3. Preoperative 3D DSA rotational angiography. The 3D reconstruction of rotational DSA (A) depicts the tridimensional topography of the arteriovenous malformation. In high-resolution patient has a favorable evolution with notable neurological recovery. The patient regained (A) depicts the tridimensional topography of the arteriovenous malformation (red arrows). In highimage (B), multiple intranidal and extubation. fusiform aneurysms were found (blue arrows). consciousness, allowing forsacullar successful resolution image (B), multiple intranidal sacullar and fusiform aneurysms were found (blue arrows). A follow-up non-contrast CT scan displayed a region of deep right fronto-temporal The selected treatment the surgical removal the arteriovenous A follow-up non-contrast CT scaninvolved displayed a region of deep rightof fronto-temporal hypodensity, indicative of aapproach post-surgical sequelae (Figure 4). Additionally, the CT scan hypodensity, indicative of a post-surgical sequelae (Figure 4). Additionally, the CT scan malformation (AVM) at the right anterior choroidal artery and the evacuation of a significant identified areas of hemorrhage, which were deemed not to require further surgical intervenidentified areas of hemorrhage, which were deemed not to require further surgical intervendeep frontotemporal intraparenchymal hematoma on the right side. Postoperatively, tion (Figure 5). Subsequent control angiography of the right carotid artery confirmed the the tion (Figure 5). Subsequent control angiography of the right carotid artery confirmed the patient has a favorable evolution with notable neurological recovery. The patient regained complete excision of the AVM, with the preservation of the pathway of the right anterior complete excision of thefor AVM, with the preservation of the pathway of the right anterior consciousness, allowing successful extubation. choroidal artery (Figure 6). The patient was then managed with conservative treatment, rechoroidal artery (Figure 6). The patient was then managed with conservative treatment, A follow-up non-contrast CT scan displayed a region of deep right fronto-temporal sulting in a in favorable clinical progression andand substantial neurological improvement. After resulting a favorable clinical progression substantial neurological improvement. hypodensity, indicative of a post-surgical sequelae (Figure 4). Additionally, the CT scan 2 weeks of hospitalization, at the time of discharge, the patient’s left hemiparesis had After 2 weeks of hospitalization, at the time of discharge, the patient’s left hemiparesis imidentified areas hemorrhage, whichResearch were deemed not to require further surgical proved to 3/5 onof the Medical Research Council (MRC) scale and assigned GCS was 12 points had improved to 3/5 on the Medical Council (MRC) scale and assigned GCSintervenwas tion (Figure 5). Subsequent control angiography of the right carotid artery confirmed 12 response—3 points (eye response—3 points, verbal response—4 points,response—5 motor response—5 (eye points, verbal response—4 points, motor points).points). the complete excision of the AVM, with the preservation of the pathway of the right anterior choroidal artery (Figure 6). The patient was then managed with conservative treatment, resulting in a favorable clinical progression and substantial neurological improvement. After 2 weeks of hospitalization, at the time of discharge, the patient’s left hemiparesis had improved to 3/5 on the Medical Research Council (MRC) scale and assigned GCS was 12 points (eye response—3 points, verbal response—4 points, motor response—5 points). Figure 4. Postoperative CT scan, malformation resection shown. All three sections of the CT scan Figure 4. Postoperative CT scan, malformation resection shown. All three sections of the CT scan (A—axial section, B—frontal section, C—sagittal section) indicate a total resection of the arteriove(A—axial section, B—frontal section, C—sagittal section) indicate a total resection of the arteriovenous nous malformation (red arrows), and the axial section of CT scan (A) depicts a small portion of an malformation (red arrows), and the axial section of CT scan (A) depicts a small portion of an intraparenchymal hematoma (blue arrow). intraparenchymal hematoma (blue arrow). Figure 4. Postoperative CT scan, malformation resection shown. All three sections of the CT scan (A—axial section, B—frontal section, C—sagittal section) indicate a total resection of the arteriovenous malformation (red arrows), and the axial section of CT scan (A) depicts a small portion of an intraparenchymal hematoma (blue arrow). Medicina 2024,2024, 60, x60, FOR Medicina 302PEER REVIEW 5 of 95 of 9 Medicina 2024, 60, x FOR PEER REVIEW 5 of 9 Figure 5. Postoperative CT scan, hematoma. Those images (A—axial section, B—frontal section, Figure Postoperative CT scan, scan,hematoma. hematoma.Those Thoseimages images (A—axial section, B—frontal section, Figure5. 5. section) Postoperative (A—axial section, B—frontal section, C—sagittal show CT a persistent pan ventricular and intraparenchymal hematoma (red arrow), C—sagittal section) and intraparenchymal intraparenchymal hematoma hematoma(red (red arrow), C—sagittal section) show show aintraventricular a persistent persistent pan pan ventricular ventricular as well as the contralateral infiltrationand of the hematoma (blue arrows). arrow), as infiltrationof ofthe thehematoma hematoma(blue (bluearrows). arrows). aswell wellas as the the contralateral contralateral intraventricular intraventricular infiltration Figure 6. Postoperative 2D DSA. The image represents a normal diameter of the anterior choroidal Figure6. 6. Postoperative Postoperative 2D represents a normal diameter of the choroidal Figure 2DDSA. DSA.The Theimage image represents a normal diameter of anterior the anterior choroidal artery (red (red arrow), arrow), with with the total ablation ofofthe right temporal arteriovenous malformation being artery the total ablation the right temporal arteriovenous malformation artery (red arrow), with the total ablation of the right temporal arteriovenous malformationbeing being achieved (blue arrow). achieved (blue arrow). achieved (blue arrow). Discussion 3.3.Discussion Theprimary primaryaim aimof oftreating treatingbrain brainarteriovenous arteriovenousmalformations malformations isispredominantly predominantly to to The The primary aim of treating brain arteriovenous malformations is predominantly preventhemorrhagic hemorrhagicevents, events,though thoughititmay mayalso alsoextend extendto tocontrolling controllingseizures seizuresor orhalting haltingthe the to prevent prevent hemorrhagic events, though it may also extend to controlling seizures or halting progression of ofneurological neurological deficits deficits [17]. [17]. Microsurgery, Microsurgery,which whichinvolves involvesaacraniotomy craniotomyand and the progression progression neurological for deficits [17]. Microsurgery, which involves a craniotomy resection, is isofacknowledged acknowledged its complication risk treating small malformations lo- and resection, for itslow low complication riskinin treating small malformations located non-eloquent brain regions, often resulting in immediate resolution. However, cated inin non-eloquent brain regions, resulting inrisk immediate resolution. However, this loresection, is acknowledged for its lowoften complication in treating small malformations this approach is invasive. Stereotactic radiosurgery (SRS), a precise irradiation method, is this approach is invasive. Stereotactic radiosurgery (SRS), a precise irradiation method, is effeccated in non-eloquent brain regions, often resulting in immediate resolution. However, effective for malformations under 3.5 cm, but complete eradication may take 1 to 3 years, tive for is malformations under 3.5 radiosurgery cm, but complete eradication take 1 tomethod, 3 years, is and approach invasive. Stereotactic (SRS), a precisemay irradiation effecand success is not assured. Potential delayed complications include hemorrhage and success is not assured. Potential delayed complications include hemorrhage and radiationtive for malformations under 3.5 cm, but complete eradication may take 1 to 3 years, and radiation-induced edema orEmbolization necrosis. Embolization utilized to manage small AVMs, induced edema or necrosis. is utilized toismanage small AVMs, prepare larger success is not assured. Potential delayed complications include hemorrhage and radiationprepare ones for (radio)surgery, or sources treat potential sources of hemorrhage, such as ones forlarger (radio)surgery, or treat potential of hemorrhage, such as associated aneuinduced edema or necrosis. Embolization is utilized to manage small AVMs, prepare larger associated aneurysms. Duringmicrocatheters embolization, microcatheters are usedembolic to introduce embolic rysms. During embolization, are used to introduce materials into ones for (radio)surgery, or treat potential sources of hemorrhage, such as associated aneumaterials into the feeding the AVMs nidus. categorized Brain AVMsascategorized as either Spetzler– the feeding arteries or thearteries nidus. or Brain either Spetzler–Martin grade rysms. During embolization, microcatheters are used to introduce embolic materials Martin or V oftena necessitate multimodal treatment approach [18]. The selection into IV or Vgrade oftenIV necessitate multimodala treatment approach [18]. The selection of treatment theof feeding arteries or the Brain as either grade treatment strategies is nidus. influenced by factorscategorized such as referral patterns, availability of strategies is influenced by factors such asAVMs referral patterns, availability ofSpetzler–Martin technical resources IVtechnical or V often necessitate a multimodal treatment approach [18]. The selection of treatment resources and expertise, personal preference, health insurance policies, and a and expertise, personal preference, health insurance policies, and a shortage of randomized shortage randomized trials different treatment modalities [19–21]. strategies isofinfluenced bycontrolled factors such ascomparing referral patterns, availability of technical resources controlled trials comparing different treatment modalities [19–21]. AVMs, situated within the cerebral ventricles, are characterized as non-eloquent and expertise, personal preference, health insurance policies, and a shortage of randomized AVMs, situated within the cerebral ventricles, are characterized as non-eloquent in in terms positioning. However, their controlled trials comparing different treatment modalities terms of oftheir theirimmediate immediateanatomical anatomical positioning. However,[19–21]. their treatment treatment isisassociated associated with aa high-risk high-risk profile, predominantly due to the frequent presence of venous with profile, predominantly due to the frequent presence of deep venous drain- in AVMs, situated within the cerebral ventricles, are characterized as deep non-eloquent drainage systems. Furthermore, the surgical resection of these AVMs necessitates traversal age systems. Furthermore, the surgical resection of these AVMs necessitates traversal 3. Discussion terms of their immediate anatomical positioning. However, their treatment is associated through eloquent cortical areas, therebydue elevating complexity and potential risk of the with a high-risk profile, predominantly to thethe frequent presence of deep venous drainprocedure [22]. Moreover, the safe excision of ventricular AVMs presents a significant age systems. Furthermore, the surgical resection of these AVMs necessitates traversal through eloquent cortical areas, thereby elevating the complexity and potential risk of the procedure [22]. Moreover, the safe excision of ventricular AVMs presents a significant Medicina 2024, 60, 302 6 of 9 through eloquent cortical areas, thereby elevating the complexity and potential risk of the procedure [22]. Moreover, the safe excision of ventricular AVMs presents a significant surgical challenge. This complexity is largely due to their vascular supply, which commonly includes the anterior choroidal artery (AChoA) and the posterior choroidal artery (PChoA). Additionally, the deep-seated location of these AVMs within the confines of a restricted surgical field further complicates their resection [23,24]. In the context of Gamma Knife Surgery (GKS) for ventricular arteriovenous malformations (AVMs), there have been reports of favorable obliteration outcomes, with a rate of approximately 77% achieved at a five-year follow-up period. However, it is noteworthy that the incidence of rebleeding during latency periods post-GKS for ventricular AVMs is comparatively higher than that observed in AVMs located at other anatomical sites [25]. The microsurgical excision of cerebral AVMs entails meticulous dissection to access the feeding arteries, the segmentation of the nidus and draining veins, and the minimal coagulation of the nidus. An analysis of excised AVM specimens reveals a complex vascular network with large-caliber, winding vessels, some linked to draining veins, underscoring their role in the venous aspect of the AVM. The nidus typically exhibits numerous looping formations on its surface [26]. The outcomes and postoperative complications of brain arteriovenous malformations differ markedly between patients treated with stereotactic radiosurgery and those undergoing microsurgery. Factors predictive of successful AVM obliteration post-radiosurgery include a smaller AVM size, presence of a single draining vein, lower Spetzler–Martin grade, higher margin or maximum dose, male gender, and prior history of hemorrhage [27,28]. Obliteration rates following SRS vary from 54% to 92%, with catheter angiography serving as the gold standard for diagnostic assessment. However, there is ongoing debate regarding the degree of hemorrhage protection provided by radiosurgery during the latency period, typically spanning 1–3 years. While reported hemorrhage rates during this period range from 1.6% to 9%, it is broadly acknowledged that the risk does not significantly differ from the pre-treatment period. The effectiveness of preradiosurgical embolization in enhancing SRS outcomes has shown mixed results; some studies, primarily from the pre-Onyx era, demonstrate obliteration rates of 60%-81% using this combined approach, whereas others report reduced obliteration rates associated with preradiosurgical embolization [29–31]. Volume-staged stereotactic radiosurgery is a potential treatment for large AVMs, known for its efficacy in controlling and obliterating these lesions. However, its application should be considered only after a meticulous, collaborative decision-making process by experienced neurosurgeons, endovascular specialists, and radio-oncologists [32]. The positioning of AVMs appears to have a negligible impact on the likelihood of eliciting radiographic alterations. However, it significantly influences the correlation between these imaging changes and the manifestation of clinical symptoms. Following radiosurgery, approximately 30% of patients exhibit new areas of high T2 signal intensity in the brain tissue surrounding the irradiated AVM nidus. These imaging changes typically emerge within a timeframe of 1 to 24 months post-radiosurgery [33]. The anterior choroidal artery (AChA) is known to supply blood to various intracranial tumors, particularly those located in the lateral ventricle, such as meningiomas, choroid papillomas [34], and gliomas [35]. Cerebral angiography often reveals these tumors to be profusely vascularized, primarily by the AChA, though additional arterial sources like the thalamoperforating or posterior choroidal arteries may also contribute [36]. Given their highly vascular nature, targeting feeders from the AChA before surgery can diminish the risk of hemorrhage and simplify surgical interventions. Consequently, preoperative embolization is advocated for to potentially reduce operative duration and is therefore recommended [37]. Arteriovenous malformations supplied by the anterior choroidal artery pose significant challenges in treatment, notably due to the elevated risk of neurological deficits postsurgery. In 1984, Fujita et al. documented the successful excision of AChA-fed AVMs, noting that factors such as the AVM’s origin from the cisternal segment of the AChA and a Medicina 2024, 60, 302 7 of 9 reduced distance between the lesion and the corticospinal tract were favorable for surgical removal [38]. The embolization of the AChA has become a recognized approach either as a precursor to surgery and radiation therapy or as an independent curative method. The goals of preoperative embolization include the obliteration of deep feeding arteries and the stabilization of AVM-associated aneurysms [39]. For instance, in 2017, Lv et al. successfully performed curative embolization in three out of four AVM cases via the AChA, with the fourth case aiding in pre-surgical preparation [16]. Nevertheless, embolization via the AChA is intricate and entails considerable risk, given that the AChA nourishes essential brain structures and lacks collateral circulation. The utilization of advanced microcatheter techniques is critical to mitigate ischemic complications. Elkordy et al., in 2017, reported enduring hemiparesis in two out of eight patients following AChA embolization for ruptured AVMs, underscoring the substantial ischemia risk [40]. To reduce these risks, some practitioners advocate for superselective provocative testing using propofol and monitoring with motor-evoked potentials. Moreover, advancements in microcatheter technology, such as the creation of smaller, flow-directed catheters, have lessened the complications associated with catheterization, thereby enabling deeper catheterization in dilated AChAs that supply AVMs [41]. Mochizuki et al. in 2023 achieved the successful embolization of AVMs supplied by the AChoA and PChoA. This was accomplished by meticulously navigating the microcatheter to a more distal and appropriate feeder vessel, a technique that remarkably resulted in the procedure being completed without any complications [13]. It is imperative to account for anatomical variations, as they can predispose to unforeseen complications during medical procedures. Moreover, as exemplified in the two cases reported in this context, particular attention should be paid to the anastomotic connections between the AChoA and PChoA, as well as between the PChoA and the anterior cerebral artery. These vascular interconnections can lead to inadvertent occlusions resulting from excessive embolization, a phenomenon that occurs due to the interconnected nature of these blood vessels [41,42]. 4. Conclusions In summarizing our study, arteriovenous malformations are acknowledged as intricate neurovascular entities, often accompanied by multiple complications. Concerning their overall management, endovascular therapy is extensively discussed in current literature as a comparatively safer approach for such cases. Our article features a rare instance of a choroidal AVM that was treated using microsurgical techniques, considering the eloquent localization. Additionally, our research delves into the decision-making process between endovascular and microsurgical methods, while also highlighting innovative techniques in managing this unique clinical situation. Our case presentation sheds light on the established knowledge surrounding this pathology, including the current treatment methodologies. We also delve into the risks associated with treating this condition. The necessity for the development of novel treatment and diagnostic methods is evident, with the aim of enhancing disease control and enabling a greater proportion of patients to experience improved recovery outcomes. Author Contributions: Conceptualization, C.T.; methodology, C.T. and R.-A.C.-B.; investigation, R.-A.C.-B. and B.-G.B.; resources, L.A.G.; writing—original draft preparation, B.-G.B. and A.V.C.; writing—review and editing, A.D.C.; visualization, C.T.; supervision, A.V.C.; funding acquisition, A.V.C. All authors have read and agreed to the published version of the manuscript. Funding: This research received no external funding. Institutional Review Board Statement: The study was conducted in accordance with the Declaration of Helsinki, and approved by the Ethics Committee (approval code: 2/2024, date: 8 February 2024) of National Institute of Neurology and Neurovascular Diseases, Bucharest, Romania. Informed Consent Statement: Written informed consent has been obtained from the patient(s) to publish this paper. Medicina 2024, 60, 302 8 of 9 Data Availability Statement: No new data were created or analyzed in this study. Data sharing is not applicable to this article. 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