Diagnostic Cerebral Angiogram Research Articles

Abstract Number ‐ 84: Importance of Early Detection and Treatment of Traumatic Intracranial Pseudoaneurysms Prior to Decompressive Hemicraniectomy

Introduction Intracranial pseudoaneurysms are rare lesions that represent less than 1% of all intracranial aneurysms.1They typically occur due to disruption of the arterial wall layers and subsequent extramural/extraluminal hematoma formation following traumatic brain injury, resulting in a higher risk of rebleeding than that of saccular cerebral aneurysms.2Pseudoaneurysms have higher incidence in children and young adults, and given their association with high morbidity and mortality, early detection and management is essential.2‐4The purpose of this study is to highlight the importance of early recognition and management of traumatic pseudoaneurysms prior to decompressive hemicraniectomy. Methods This is a case report of a six‐year‐old previously healthy male who presented as a level 1 trauma alert after sustaining a gunshot wound to the face while manipulating an unsecured weapon at his residence. Upon arrival, lack of airway protection requiring intubation, entry wound to the anterior forehead, and diffuse forehead and periorbital edema were observed. CT head demonstrated multicompartmental hemorrhage with 6mm right to left midline shift and diffuse cerebral edema. CTA head and neck noted possible thrombosed right anterior cerebral artery (ACA) pseudoaneurysm in the right frontoparietal region (Figure 1‐A). Prior to decompressive hemicraniectomy, neuro‐endovascular consultation was obtained, and emergent cerebral angiogram was recommended. This case highlights the findings demonstrated on cerebral angiography, the technique by which the pseudoaneurysm was detected and secured, and the importance of doing so prior to further neurosurgical interventions. Results The patient was taken for diagnostic cerebral angiogram via femoral artery access. Initial angiographic run of the right internal carotid artery demonstrated distal right pericallosal artery slowing without clear evidence of underlying vascular injuries. Given concern for underlying thrombosed pseudoaneurysm and its parent branch, selective catheterization of the proximal pericallosal artery off the distal ACA was performed. Gentle angiographic run was obtained via microcatheter that demonstrated superior parietal artery pseudoaneurysm without active extravasation (Figure 1‐B). The microcatheter was advanced and placed in the proximal portion of the pseudoaneurysm sac and five platinum coils were deployed to fully obliterate the pseudoaneurysm and its parent feeder while protecting the adjacent paracentral artery (Figure 1‐C, 1‐D). Following completion of the endovascular procedure, the patient was transferred to the operative room for right decompressive hemicraniectomy and clot evacuation, which were completed successfully. Conclusions Prompt detection and securement of traumatic intracranial pseudoaneurysms are essential prior to invasive neurosurgical interventions to reduce risk of recurrent bleeding. Selective angiographic evaluation of the parent injured vessel(s) is crucial for optimal assessment of the underlying lesion. Neuro‐endovascular interventions including coil embolization, stenting, flow‐diverter implantation, and parental artery occlusion have emerged as alternatives to conventional neurosurgical management.2 This case highlights the successful early detection and treatment of a traumatic intracranial pseudoaneurysm with coil embolization followed by uncomplicated decompressive hemicraniectomy.

Abstract Number ‐ 236: Pure Arterial Malformations: A Case Report

Introduction Pure arterial malformations are dilated, overlapping, and tortuous arteries forming a mass of arterial loops without a venous component. These malformations are rare, with limited cases reported in the literature. Affecting any of the intracranial arteries, they are usually found incidentally and often have a benign course. Methods We present a case of a pure arterial malformation in a young female with hyperprolactinemia. Furthermore, we review the literature and provide an updated summary of these malformations. Results A 28‐year‐old female with a history of infantile hemangiomas, polycystic ovary syndrome, and hyperprolactinemia presented with acne, mild hirsutism, and galactorrhea. Her neurological exam was normal. Magnetic Resonance Imaging (MRI) of the brain with and without contrast ruled out a prolactinoma but revealed a 3 cm vascular malformation at the margin of the left cavernous sinus extending posteriorly into the anterior left perimesencephalic cistern. Initial differentials included a pial arteriovenous malformation or less likely a dural arteriovenous fistula. She underwent a diagnostic cerebral angiogram which revealed a pure arterial malformation without arteriovenous shunting. This was composed of dysplasia of the left posterior communicating artery and anterior choroidal arteries. Stenosis of the left internal carotid artery distally with collateral support into the left anterior cerebral artery and middle cerebral artery was also noted. Lesser changes were noted in the right side with reconstitution of the right anterior cerebral artery from collaterals. Genetic testing for vascular malformation syndromes, including genes known to be associated with hereditary hemorrhagic telangiectasia, was negative. Repeat MRI/MRA done 8 months from the initial scan was stable with no abnormal large arterial venous shunting or definite saccular aneurysm formation noted. Conclusions Although rare, pure arterial malformations should be considered in the differential diagnosis for patients presenting with a cranial vascular malformation. Management of these lesions is usually conservative given their lack of arteriovenous shunting and low risk of rupture, with only a few cases undergoing surgery or endovascular treatment.

An audit of patient radiation doses in interventional radiology at a South African hospital.

Interventional radiology (IR) is becoming more relevant in patient care and is associated with increased patient radiation exposure and radiation-induced adverse effects. Diagnostic reference levels (DRLs) are crucial for radiation control. There is a paucity of published DRLs for IR in South Africa and sub-Saharan Africa. This study aimed to determine local DRLs for fluoroscopically-guided IR procedures and compare the achieved DRLs with published local and international DRLs. Retrospective, descriptive, single-centre study. Kerma air product (KAP), reference point air kerma (Ka,r) and fluoroscopy time (FT) were collected for patients (12 years and older) who underwent IR procedures at a university hospital from 01 January 2019 to 31 December 2019. The 75th percentile of the distribution of each dose parameter (KAP, Ka,r and FT) per procedure was calculated and taken as the local diagnostic reference levels (LDRL). The established LDRLs were compared to published DRLs. A total of 564 cases were evaluated. The 13 most frequent procedures (with 15 or more cases) represented 86.1% (487/564). Percutaneous transhepatic biliary drainage was the most common procedure (n = 146, 25.9%). Diagnostic cerebral angiogram DRLs exceeded the published DRL data ranges for all parameters (DRL 209.3), and interventional cerebral angiogram exceeded published ranges (DRL 275). Uterine artery embolisation (UAE) exceeded these ranges for KAP and Ka,r. (KAP-954.9 Gy/cm2, Ka,r-2640.8 mGy). The LDRLs for diagnostic cerebral angiogram, interventional cerebral angiogram and UAE exceeded published international DRL ranges. These procedures require radiation optimisation as recommended by the International Commission on Radiological Protection (ICRP). In addition to informing radiation protection practices at the level of the institution, the established LDRLs contribute towards Regional and National DRLs.

Headache as Initial Presentation of Human Chronic Necrotizing Granulomatous Meningoencephalitis

Objective Chronic necrotizing and granulomatous meningoencephalitis is an idiopathic inflammatory disease with possible autoimmune mediated delayed type hypersensitivity response. It commonly affects the central nervous system of dogs and cats. However, this inflammatory disease has rarely been described in humans. Background A 69-year-old right-handed woman presented with worsening subacute headaches that were intermittent, sharp and holocephalic in nature which worsened with coughing and/or laughing. Her initial neurological examination was unremarkable. MRI of the brain revealed multifocal enhancing lesions and edema as well as multifocal signal abnormality throughout the supratentorial and infratentorial parenchyma. Her cerebrospinal fluid showed elevated opening pressure, elevated nucleated cells, elevated protein and normal glucose. CSF cytology, gram stains and cultures were unremarkable. Possibility of sarcoidosis, mycobacterium and fungal etiologies were ruled out. Other work up included but not limited to MRA head, MRV head, diagnostic cerebral angiogram, extensive serum and CSF autoimmune labs were also unremarkable. She underwent a brain biopsy which showed necrotizing granulomatous inflammation with associated dystrophic calcification. Patient was started on high dose methylprednisolone followed by a 6-week prednisone taper. There was a complete resolution of her symptoms, as well as improvement in her follow up MRI brain over a six month period. Design/Methods N/A. Results N/A. Conclusions We describe what we believe would be the third reported case of necrotizing granulomatous meningitis of an unknown cause in humans. This case demonstrates the response of necrotizing granulomatous meningoencephalitis in humans to steroid therapy. Yet, further studies are necessary to determine symptomatology and pathogenesis, as well as the treatment in humans.

Rate of periprocedural stroke in diagnostic cerebral angiograms comparing transradial versus transfemoral access.

Transradial access for neurointerventional procedures has increased in popularity over the past few years due to data from extrapolated interventional cardiology studies, patient preference, and early reports of feasibility using this approach. Our aim was to evaluate the incidence of periprocedural stroke in patients undergoing transradial versus transfemoral access for diagnostic cerebral angiograms. We retrospectively reviewed our neurointerventional database and identified all patients who underwent a diagnostic angiogram between May 2019 and July 2021. Patients were further divided into transradial versus transfemoral access. In patients with postprocedural stroke, symptoms and National Institute of Health Stroke Scale score were recorded. Pertinent laboratory values and procedural data was reviewed, including COVID status, platelet count, International normalized ratio (INR), Glomerular filtration rate (GFR), vessels catheterized, amount of contrast used, and fluoroscopy time. Imaging work-up for stroke symptoms was reviewed, if available. Thousand two-hundred thirty eight diagnostic cerebral angiograms with 656 patients (53%) undergoing transradial access. Stroke symptoms after angiogram were only observed in the transradial group (5 patients; 0.4% total and 0.8% among radial access cases, respectively). Symptoms included word finding difficulty, paresthesia, or weakness. Three patients underwent cross-sectional imaging, computed tomography was negative in all three patients. Magnetic resonance imaging showed small, scattered infarcts in two patients. All symptoms resolved without additional hospitalization. In our experience, using transradial access for diagnostic cerebral angiograms was associated with a low but not negligible incidence of periprocedural strokes. Patient anatomy should be evaluated prior to selection of vascular access. Patients should be made aware of a slightly higher periprocedural stroke risk with transradial access.

ODP324 Internal Carotid aneurysm inside a pituitary macroadenoma: case study and literature review

Abstract BACKGROUND: Coexisting pituitary adenoma (PA) and intracranial aneurysms (IA) is relatively frequent. However, the finding of an aneurysm inside a PA is extremely rare. We report a patient with pituitary macroadenoma with an embedded internal carotid artery (ICA) aneurysm, who presented with anterior hypopituitarism. CLINICAL CASE: 73 y. o. black female presented after a fall secondary to orthostastic hypotension. In the ER her BP was 78/50 mmHg, HR 76/min sinus rhythm. She reported fatigue, presyncope, and 20 lbs weight loss in the preceding 3 months. CT head without contrast showed a sellar mass. Pituitary MRI confirmed a 20×24×29 mm sellar mass consistent with a macroadenoma extending laterally to both cavernous sinuses with bilateral encasement of ICAs, superiorly elevating optic chiasm, and mild extension to the left Meckel's cave. The study also incidentally showed a > 5 mm ICA aneurysm embedded within the macroadenoma. Diagnostic cerebral angiogram demonstrates a medially directed left superior hypophyseal ICA aneurysm measuring 5.4×4. 0 mm with a 3.5 mm neck. The patient denied headaches, peripheral vision loss, or polyuria. On examination her weight was 154 lbs, height 5'6", normal visual field testing, and no neurologic deficits. Endocrine testing was consistent with anterior hypopituitarism: ACTH 17 pg/mL (10-48), Cortisol 4.7 mcg/dL (6-18.4), TSH 1.4 mIU/L (0.4- 4. 0), FT4 0.7 (0.7-1.9 ng/dL), IGF1 7 ng/mL (55-162), Prolactin 38.3 ng/mL (4.8- 23.3), and FSH 6.6 IU/mL (20-138). Clinical improvement followed hydrocortisone and levothyroxine replacement. Patient was discharged home with a plan for outpatient endocrine follow up and subsequent endovascular intervention. Unfortunately, she presented a few weeks later with pulmonary embolism, for which she was treated with Eliquis. Given high risk of bleeding, the plan for endovascular embolization was postponed. Patient was educated about sick day rules and is set for routine endocrine visit and periodic MRI surveillance of the macroadenoma. DISCUSSION: intracranial aneurysms appear to occur more frequently in association with PAs than among the general patient population. In 2 cohort of patients with PA, 5.4-7.3% had coexisting IAs, the majority of which are outside the pituitary region. However, the presence of an aneurysm embedded within a PA, as in our case, is very rare, and most are discovered by accident. In such cases, although spontaneous aneurysm rupture or pituitary apoplexy is extremely rare, misdiagnosis of the embedded aneurysm can potentially result in catastrophic outcomes if it is not appropriately recognized and addressed prior to pituitary surgery. Cerebral angiography with embolization or coiling of the aneurysm prior to hypophysectomy can decrease the risk of perioperative rupture or bleeding. In our case, given the risk of bleeding while on anticoagulation therapy, the plan for endovascular intervention was postponed. Presentation: No date and time listed

Fusiform Cerebral Aneurysm and Atrial Myxoma

A 24-year-old woman presented with a seizure-like episode of left hemibody sensory loss. Magnetic resonance imaging and magnetic resonance angiography revealed multiple distal fusiform cerebral aneurysms requiring angiographic evaluation and possible endovascular treatment. On preoperative workup, transthoracic echocardiography revealed a large, 4.1× 2.1 cm, mobile left atrial mass prolapsing into the left ventricle during diastole. Multidisciplinary discussion among representatives from neurosurgery, cardiology, and cardiothoracic surgery determined the plan to proceed with diagnostic cerebral angiogram and aneurysm embolization before moving forward with heart surgery. Cerebral angiogram revealed several right distal middle cerebral artery fusiform aneurysms and a right distal posterior inferior cerebellar artery fusiform aneurysm. Subsequently, the patient underwent endovascular coil embolization of the largest distal M4 fusiform aneurysm, measuring 3.3× 3.2 mm in maximal diameter. The patient recovered to baseline in the surgical intensive care unit and was discharged home on postoperative day 7 with close neurosurgical and cardiology follow-up.

Transradial versus transfemoral arterial approach for cerebral angiography and the frequency of embolic events on diffusion weighted MRI

BackgroundThe radial artery approach has become popular as a ‘radial first’ strategy for arterial access in neuroangiography and neurointerventions. Recent studies have shown that transradial arterial access (TRA) for cerebral...

Reversible focal neurologic deficits as a complication of diagnostic cerebral angiogram (P14-10.007)

Reversible focal neurologic deficits as a complication of diagnostic cerebral angiogram (P14-10.007)

Angiographic Pulse Wave Coherence in the Human Brain.

A stroke volume of arterial blood that arrives to the brain housed in the rigid cranium must be matched over the cardiac cycle by an equivalent volume of ejected venous blood. We hypothesize that the brain maintains this equilibrium by organizing coherent arterial and venous pulse waves. To test this hypothesis, we applied wavelet computational methods to diagnostic cerebral angiograms in four human patients, permitting the capture and analysis of cardiac frequency phenomena from fluoroscopic images acquired at faster than cardiac rate. We found that the cardiac frequency reciprocal phase of a small region of interest (ROI) in a named artery predicts venous anatomy pixel-wise and that the predicted pixels reconstitute venous bolus passage timing. Likewise, a small ROI in a named vein predicts arterial anatomy and arterial bolus passage timing. The predicted arterial and venous pixel groups maintain phase complementarity across the bolus travel. We thus establish a novel computational method to analyze vascular pulse waves from minimally invasive cerebral angiograms and provide the first direct evidence of arteriovenous coupling in the intact human brain. This phenomenon of arteriovenous coupling may be a physiologic mechanism for how the brain precisely maintains mechanical equilibrium against volume displacement and kinetic energy transfer resulting from cyclical deformations with each heartbeat. The study also paves the way to study deranged arteriovenous coupling as an underappreciated pathophysiologic disturbance in a myriad of neurological pathologies linked by mechanical disequilibrium.

Transradial versus Transfemoral Approach for Neuroendovascular Procedures: A Survey of Patient Preferences and Perspectives

Studies about the transradial technique and experience with this approach abound in the neurointerventional literature, but studies focusing on patient perspectives and preferences with respect to transfemoral or transradial access are scarce. Patients from our center who underwent both transradial and transfemoral approaches for diagnostic and interventional cerebral angiograms on distinct occasions between January 2016 and January 2021 were identified and interviewed by phone regarding their experience with these access approaches. The first question was regarding the choice for an eventual next procedure (radial, femoral, or no preference). The second question addressed reasons (pain, bruising, complications, recovery time, mobility, failure of one approach, and comfort associated with puncture of the respective area). Forty-four patients were interviewed. Thirty-one (70.4%) preferred radial, 9 (20.5%) preferred femoral, and 4 (9.1%) had no preference. Most frequent reasons for radial preference were recovery time (67.7%), bruising (51.6%), and pain (48.4%). Most frequent reasons in femoral preference were pain (55.6%), mobility (33.3%), and failure of the other approach (33.3%). Recovery time (67.7% vs. 22.2%; P= 0.023) and comfort of puncturing the area (45.2% vs. 0%; P= 0.015) were significantly more frequent reasons for radial preference, whereas failure of the other approach (0% vs. 33.3%; P= 0.008) was a significantly more frequent reason for femoral preference. Most patients preferred the transradial approach. Evaluating the reasons behind their preference can help operators to better understand patient perspectives and improve quality of care.

Salvage Superficial Temporal Artery to Middle Cerebral Artery Direct Bypass Using an Interposition Graft for Failed Encephaloduroarteriosynangiosis in Moyamoya Disease

Moyamoya disease may present with either hemorrhagic or ischemic strokes. Surgical bypass has previously demonstrated superiority when compared to natural history and medical treatment alone. The best bypass option (direct vs. indirect), however, remains controversial in regard to adult ischemic symptomatic moyamoya disease. Multiple studies have demonstrated clinical as well as angiographic effectiveness of direct bypass in adult hemorrhagic moyamoya disease. In particular, there are limited data regarding strategies in the setting of failed indirect bypass with recurrent hemorrhagic strokes. Here, we describe a salvage procedure. We describe a case of a 52-year-old man who presented with hemorrhagic moyamoya disease and failed previous bilateral encephaloduroarteriosynangiosis (EDAS) procedures at an outside institution. On a 3-year follow-up diagnostic cerebral angiogram, no synangiosis was noted on the right side and only minimal synangiosis was present on the left. The left hemisphere was significant for a left parietal hypoperfusion state. We performed a salvage left proximal superficial temporal artery to distal parietal M4 middle cerebral artery bypass using the descending branch of the lateral circumflex artery as an interposition graft with preservation of the existing EDAS sites. The patient underwent the procedure successfully and recovered well with resolution of headaches and no further strokes or hemorrhages on the 1-year follow-up magnetic resonance imaging of the brain. This case presents the use of a salvage direct bypass technique for recurrent symptomatic hemorrhagic moyamoya disease after failed EDAS. The strategy, approach, and technical nuances of this unique case have implications for revascularization options.

The Effects of Diagnosis-Related Group Payment on Diagnostic Cerebral Angiograms through a Transradial and Transfemoral Approach: A Comparative Observational Study.

Background Cerebral angiography is an X-ray examination technique widely used in hospitals. At present, it is mainly divided into two kinds of angiography examination: transfemoral artery and transradial artery puncture. The diagnosis-related group (DRG) system is a new type of payment standard recognized internationally, but its impact on medical care and health outcomes is currently controversial. Aim In this study, we conducted a comparative study on two invasive approaches, transradial artery and transfemoral artery puncture and observed whether DRG had an impact on the quality of the medical process. Methods We compared and analyzed patients undergoing cerebral angiography via the femoral artery and radial artery puncture by recording the relevant parameters and comfort scale scores (GCQ) during the operation, as well as postoperative complications. At the same time, we observed the proportion of different puncture routes and the success rate of cerebral angiography before and after the implementation of a DRG payment simulation. Results The results of the comparative analysis of patients' transradial artery and transfemoral artery puncture angiography showed that the puncture success rate (99.1% vs. 97.2%, P > 0.05), angiography success rate (97.3% vs. 95.1%, P > 0.05), and X-ray radiation time (4.82 vs. 5.15 min, P > 0.05) demonstrated no significant difference. The ambulation time (1.52 vs. 12.06 h, P < 0.05), puncture time (22.42 vs. 31.02 min, P < 0.05), and complications (3.57% vs. 9.03%, P < 0.05) of the radial artery group were significantly lower than those of the femoral artery group. In contrast, the GCQ score of the radial artery group at each stage after angiography was significantly higher than that of the femoral artery group (P < 0.05). Compared with before the DRG simulation, the proportion of cerebral angiography with transradial artery puncture increased significantly after its implementation. Conclusion Compared with transfemoral cerebrovascular angiography, transradial cerebrovascular angiography has many advantages, such as less local damage, less pain, less postoperative bed-rest time, significantly lower incidence of total complications, and a lower cost. Following the implementation of the DRG payment method, the quality of the angiography medical process improved.

Comparison of radiation exposure and clinical outcomes between transradial and transfemoral diagnostic cerebral approaches: a retrospective study

ObjectiveTo identify and compare patient and procedural variables that are associated with a high radiation dose exposure and worse clinical outcomes between transradial arterial (TRA) and transfemoral arterial (TFA) approaches.DesignThis...

Comparison of the Safety, Efficacy, and Procedural Characteristics Associated with Proximal and Distal Radial Access for Diagnostic Cerebral Angiography

ObjectivesRadial access is an increasingly popular approach for performing cerebral angiography. There are two sites for radial artery puncture: proximal transradial access (pTRA) in the wrist and distal transradial access (dTRA) in the snuffbox. These approaches have not been directly compared. Materials and methodsConsecutive diagnostic cerebral angiograms performed at a single institution were retrospectively reviewed. Outcomes included fluoroscopy time, radiation dose, contrast volume, time to obtain access, procedure duration, and time to discharge home. Success rates as well as minor and major complication rates associated with each approach were also compared. Multivariate linear regression models were used to determine the relationship between access site and outcomes while adjusting for covariates. ResultsA total of 287 angiograms on 244 patients met the inclusion criteria. pTRA was associated with shorter fluoroscopy time (ß -2.54, 95% CI -4.18 - -0.9, p = 0.003) and lower radiation dose (ß -242.89, 95% CI -351.55 - -134.24, p < 0.001), but not contrast volume. Time to obtain access, procedure duration, and time to discharge home were similar between approaches. A total of 10 minor complications occurred with similar rates for each approach (8 for dTRA, 2 for pTRA, p = 0.168) and there were no major complications. The conversion rate to femoral access was low (1.05% overall) and did not differ with approach. ConclusiondTRA and pTRA are associated with similarly high rates of safety and efficacy. Procedure duration, time to obtain access, and time to discharge did not differ between approaches.

Abstract 1122‐000124: Dural Arteriovenous Fistula and Implications in Aneurysmal Genesis

Introduction : There is a reported association of cerebral arteriovenous malformations and aneurysms, however, data regarding patients presenting with dural arteriovenous fistulas (dAVF) and aneurysms is limited. Here, we present a patient who was incidentally diagnosed with 2 aneurysms in addition to a dAVF; and her treatment course. Previous to her diagnosis, she denied any and all symptomatology that would prompt further evaluation. Methods : Case description: 60‐year‐old female with history of hypertension, hypothyroidism and gastroesophageal reflux disease who initially presented to an outside hospital after a motor vehicle collision in 2016, at that time she reports being diagnosed with multiple aneurysms; but was lost to follow up. In 2020 she was referred to interventional neuroradiology and underwent diagnostic digital cerebral angiogram. Which reported a 13 × 12 × 13.3 mm left para‐ophthalmic internal carotid artery (ICA) aneurysm with a 7 mm neck. A 5.7 × 7.7 × 6.1 mm basilar tip artery aneurysm with a 5.6 mm neck and a right Cognard type four occipital dAVF, with feeding vessels from the right posterior cerebral artery and right occipital artery and anterograde drainage to the dural sinuses. From the time of diagnosis to the initiation of interventions, patient denied any concerning symptomatology. Treatment was initiated 4 months after diagnostic angiogram. She received 5 days of Dual Antiplatelet therapy (DAPT) with aspirin and Plavix previous to the deployment of a woven endobridge device (WEB™ 8‐3mm) into the basilar tip aneurysm; as this was felt to be the aneurysm with highest probability of rupture. Post‐operative course was unremarkable and DAPT was discontinued. Three months after WEB™ deployment, the patient underwent embolization of the right occipital dAVF with a liquid embolic agent (onyx™). Post operatively, she developed decreased peripheral vision in her left eye, though the rest of her hospitalization was unremarkable. 3 months after embolization, she underwent left para‐ophthalmic artery aneurysm flow diversion with a pipeline™ (4‐18mm) flow diverter, with an uncomplicated admission. She was subsequently evaluated by neuro‐ophthalmology who has reported a stable peripheral left eye left inferior quadrantic defect along with a supertemporal defect in her right eye. Results : Discussion: Interestingly, the patient presented 2 aneurysms, one in the anterior circulation and the most concerning, located in the posterior circulation. One could draw conclusions that the dAVF was associated with the basilar aneurysm. As dAVFs are acquired lesions, it is feasible to assume that there may be an association between both types of lesions, perhaps due to flow or pressure being exerted on weakened vessel walls, thus leading to aneurysmal formation. Conclusions : Conclusion: Because a potential for implication in the flow dynamics of the dAVF in aneurysmal formation. We have opted to use computational fluid dynamics to analyze said flow within the dAVF to better understand the causal relationship between aneurysms and dural fistulae. In the long run research into genesis of aneurysms secondary to coexisting vascular lesions could further elucidate the mechanisms by which aneurysms develop.

Abstract 1122‐000216: Evacuation of Bilateral Intracerebral Hemorrhages Using a Novel Disposable Surgiscopic System: A Case Report

Introduction : Patients presenting with intracerebral hemorrhage (ICH) face higher rates of morbidity and mortality than other stroke patients. Currently, these patients are managed by surgical intervention and decompression or medical management, depending on categorization of the hemorrhage. Simultaneous, multifocal hemorrhages are a rare presentation of ICH that portend a worse prognosis. Here we report the treatment of bilateral simultaneous ICHs in a young patient with diagnostic cerebral angiography, biopsy, and bilateral minimally invasive surgiscopic ICH evacuation in a single procedure. Methods : The patient was a young female who presented to an outside hospital after two days of progressively worsening headaches and vomiting. Her medical history was significant for systemic lupus erythematosus (SLE), hypertension, chronic migraines, and opioid use disorder. In the emergency department, her mental status deteriorated, and she was intubated. Computed tomography (CT) scan was performed and showed a right parietal 43.3 cc ICH and a left parietal 38.7 cc ICH. MR angiogram and venogram showed no evidence of vascular malformations but were suggestive of potential cerebral venous sinus thrombosis. Upon arrival, the patient remained intubated but was able to open her eyes, follow commands, and respond to stimulation. The patient was brought to the angiosuite for diagnostic cerebral angiography which revealed diffuse intermittent arterial narrowing suggestive of vasculitis and patent venous sinuses. The patient was then positioned in the prone position and bilateral parietal 1.5 cm craniectomies were performed. Surgiscopic evacuation was performed sequentially using stereotactic navigation to access and evacuate each clot. A right parietal brain biopsy was performed at the minimally invasive cortical access point. Results : Active bleeding was encountered in both hematoma sites and was treated with a combination of irrigation and monopolar cautery transmitted through the Aurora Evacuator. After complete evacuation of the hematomas on both sides, an intraoperative conebeam CT was performed, demonstrating good right‐sided evacuation and resident left‐sided hematoma. Additional evacuation was performed on the left side and repeat conebeam CT demonstrated good bilateral evacuation. CT head on post operative day 1 showed 97.7% right‐sided evacuation and 81.5% left‐sided evacuation. The patient was treated with steroids for presumed vasculitis given the angiographic findings, which was later supported by the results of the brain biopsy. The patient made a good recovery and was discharged from the hospital alert and oriented, with CN II‐XII grossly intact, no focal deficits, and 5/5 strength in all extremities. Conclusions : Minimally invasive ICH evacuation can be performed in the angiosuite for ICH‐associated with vasculitis and even multifocal ICH when appropriate. Performing the procedure in the angiosuite permits completion of the diagnostic cerebral angiogram, brain biopsy, and hematoma evacuation at the same time, accelerating time to treatment for a patient with severe, symptomatic vasculitis.

Abstract 1122‐000117: Transcranial Arterial Embolization of an dAVF: A Case Report

Introduction : We detail the management of a woman with a posterior fossa dAVF (dural arteriovenous fistula) that was unable to be treated by standard transarterial or transvenous embolization or microsurgical ligation. She underwent craniotomy for surgical exposure and direct access of her left middle meningeal artery followed by microcatheter embolization with favorable results. Methods : This is a case report, which describes a case of a difficult to access dAVF. Results : A 72 year‐old woman presented with vertigo, nausea, and vomiting one week following a fall. CT head disclosed cerebellar vermis intraparenchymal hematoma and CT head angiography was suspicious for underlying vascular malformation. Diagnostic cerebral angiogram demonstrated extensive tentorial and suboccipital dural arteriovenous fistula (dAVF) fed by branches of both middle meningeal and occipital arteries with direct cortical venous drainage and venous aneurysmal ectasia directly adjacent to the vermian hemorrhage (ruptured Cognard grade 4). Left vertebral artery angiogram demonstrated excessive tortuosity of vertebral enlarged posterior meningeal artery, which was unable to be catheterized sufficiently beyond its origin despite different microwires and microcatheters due to tortuosity. Transfemoral venous approach was also attempted, however, this was also unsuccessful and decision was made to proceed with microsurgical treatment. The following day a suboccipital craniotomy was performed, but was ultimately aborted due to nearly uncontrollable bleeding from bony exposure and dural access secondary to severe venous hypertension. The next day percutaneous endovascular treatment was attempted a second time. A small right middle meningeal artery (MMA) contribution to the fistula was embolized with liquid embolic but, again because of excessive tortuosity and insufficient microcatheter access, right MMA occlusion occurred without embolic agent reaching the fistula. Similar access related difficulties due to tortuosity were encountered in accessing the left middle meningeal and occipital arteries contributing to the fistula. Repeat transvenous access was also attempted from the occipital and right transverse sinuses, but microcatheter access to the fistula was unable to be established beyond the venous outflow from the aneurysm, and, given the risks of hemorrhage related to embolization of the venous outflow without occluding arterial inflow into the ruptured aneurysm, transvenous embolization was not performed. A few days later, after the patient was given time to recover from the prior procedures, the patient underwent left temporal craniotomy in a hybrid operating room/interventional radiology suite for direct cannulation of the left MMA. Localization of the craniotomy site over the left MMA access point was planned by transfemoral cerebral angiogram and a transcarotid/peripheral access kit was used to catheterize the left MMA directly following surgical exposure. An .017 microcatheter was advanced close to the fistula point using standard biplanar roadmap fluoroscopy, and Onyx embolization of the fistula was performed to complete occlusion, without complication. Conclusions : For cerebrovascular disorders that are inaccessible by traditional endovascular and surgical means, a hybrid approach should be considered.

Abstract 1122‐000097: Recurrent Carotid Cavernous Fistula Requiring Complex Repair of Ruptured Cavernous Carotid Aneurysm: A Case Report

Introduction : There are no studies investigating the safety and efficacy of covered stent grafts, particularly the newly developed stents such as the PK Papyrus stent, for endovascular treatment of direct carotid cavernous fistulas (CCFs). Methods : We present a case of a 75‐year‐old female who presented to the hospital with a three‐week history of worsening left eye vision, chemosis, proptosis, and partial third nerve palsy. Patient was found to have left direct Type A CCF secondary to ruptured cavernous segment carotid aneurysm. Results : The CCF was treated with coil embolization and pipeline Shield stent embolization devices with immediate stagnation and improvement of symptoms. Patient had history of an aortic mechanical valve and thus was started on warfarin and ASA. After achieving INR level of 2.5‐3.5, patient started to have recurrent swelling of the left eye associated and decreased visual acuity. Repeated diagnostic cerebral angiogram revealed residual CCF. Onyx liquid embolization and a Surpass Evolve Flow Diverter were attempted to slow the fistulization with no success. Multiple attempts for direct percutaneous superior ophthalmic vein cannulation were also unsuccessful. At this point, two coronary graft‐covered PK Papyrus stents were implanted across the fistula pouch, which resulted in immediate resolution of the CCF with evidence of persistent normal flow within left ophthalmic artery. Patient’s visual acuity and left eye movement improved. Conclusions : This case report highlights the effectiveness and safety of covered stent grafts, particularly more flexible stents such as the PK Papyrus stent, in navigating the carotid vasculature and closing direct CCFs and may be used as a first‐line technique. More large‐scale studies are warranted to investigate the safety and efficacy of using such stent grafts to treat direct CCFs in the setting of antithrombotic agents and anticoagulation.

Initial experience of subcutaneous nitroglycerin for distal transradial access in neurointerventions.

Background: Transradial access (TRA) for diagnostic and interventional neuroendovascular procedures has gained significant popularity in recent years due to its improved safety profile and appeal to patients compared with transfemoral access. However, risks of TRA include hand ischemia in cases of poor ulnar collateral circulation and inability to cannulate the radial artery due to its relatively small diameter. By accessing the radial artery distal to the superficial palmar arch where ulnar collateral blood flow arises, in the anatomic snuffbox, the risk of hand ischemia is theoretically eliminated. The use of subcutaneous nitroglycerin and lidocaine to improve rates of success in radial artery access has been reported in the cardiac literature, however, has yet to be described for neurointerventional procedures. We discuss our technique and report our initial experience using subcutaneous nitroglycerin and lidocaine cocktail for access to the distal transradial artery in a variety of neuroendovascular procedures.Methods: A retrospective review of our institution’s database of neurointerventional and diagnostic procedures performed using dTRA was conducted, and 64 patients were identified between February and December 2020. Patient demographics, clinical data, procedural details, and radiographic information were collected and analyzed.Results: A total of 64 patients underwent neurointerventional procedures using the subcutaneous injection for dTRA access. The procedures performed included diagnostic cerebral angiograms (n = 47), stent and balloon assisted aneurysm coiling (n = 5), flow diversion (n = 2), intra-saccular device placement (n = 1), mechanical thrombectomy (n = 1), tumor embolization (n = 1), middle meningeal artery embolization (n = 2), extracranial carotid stent placement (n = 2), and arteriovenous malformation embolization (n = 3). While no complications of hand ischemia were appreciated, the access site conversion rate was 3.1%; 2 cases required a switch to femoral artery access due to proximal vessel tortuosity and aortic anatomical variations, and not due to access site complication. Furthermore, on repeat angiograms by the same proceduralist, distal TRA (dTRA) was successful in 100% of the cases.Conclusion: dTRA using subcutaneous nitroglycerin and lidocaine is a safe and effective method for neurointerventional and diagnostic procedures.