Dynamic Digital Subtraction Angiography Research Articles

Frameless Co-Registration of Biplane 2D Digital Subtraction Angiography Whole Frames and 3D Rotational Angiography-Based Cone-Beam Computed Tomography Angiogram on Dedicated Software for Stereotactic Radiosurgery of Cranial Vascular Malformations.

Purpose: Given its high spatial resolution and vasculature selectivity, the cone-beam computed tomography (CT) angiography (CBCTA) image acquired by selective 3D rotational angiography (3DRA) is the most suitable 3D image for the target definition of stereotactic radiosurgery (SRS) for intracranial arteriovenous malformations (AVMs) and dural arteriovenous fistulas (DAVFs). Furthermore, the relatively low temporal resolution of 3DRA-based CBCTA can be complemented by the stereotactic co-registration of orthogonally paired 2D dynamic digital subtraction angiography (2D-DSA). The integration of 2D-DSA, which is usually limited to one or a few frames for each projection, into CBCTA and/or planning CT can be achieved only by catheter-directed angiography on the day of SRS via a dedicated image localizer under rigid frame fixation to the skull, which imposes substantial burdens on patients. This study aimed to demonstrate a novel, convenient, and significantly less invasive method for the frameless co-registration of biplane 2D-DSA whole frames and CBCTA on commercially available dedicated software, namely, Brainlab® Elements (Brainlab AG, Munich, Germany), and present its prerequisite for successful image fusion.Technical Report: Elements have afforded the following functionality: A 3D vasculature image is automatically extracted as a floating image from any 3D image series containing vascular details and then subsequently co-registered manually and automatically to a selected frame pair of 2D-DSA with a six-degree-of-freedom rigid registration. As a preclinical feasibility study, two anonymous image datasets from patients harboring cerebral AVM and transverse-sigmoid (TS) DAVF were used to verify the accuracy and practicality of Elements for the frameless co-registration of 2D/3D vascular images, particularly on the assumption of clinical workflow for the target delineation of SRS planning. The use of ordinary unsubtracted CBCTA resulted in the insufficient extraction of abutting vessels or vessels that are in close proximity to bony structures, particularly in the case of TS-DAVF, where the fistulous pouch and the affected venous sinuses were adjacent to the cranial bone. By contrast, the amount and selectivity of vasculatures and the accuracy of subsequent image fusion were significantly improved from the subtracted CBCTA. The integration of CBCTA into dynamic 2D-DSA allowed the simultaneous review of both image information by sharing any concerning point and 2D or 3D structures under a common 3D coordinate.Conclusions: Elements enable the clinically useful frameless co-registration of biplane 2D-DSA whole frames into CBCTA, for which the routine acquisition of both subtracted and unsubtracted CBCTA axial images for ordinary diagnostic purposes is an indispensable prerequisite for successful image fusion and further widespread application. This frameless integration of the 2D/3D angiogram would dramatically enhance both the frame-based and frameless SRS workflow and circumstances by allowing users to forward SRS planning well in advance before SRS, along with the omission of invasive angiography on the day of SRS, and would broaden the implementation of frameless SRS. Furthermore, the comprehensive alternating interactive review of the 2D/3D integrated angiogram leads to a more in-depth quasi-4D understanding of the affected angioarchitectures compared with the separate viewing of each image.

Is malignant edema and hemorrhage after occlusion of high-flow arteriovenous malformation related to the size of feeding arteries and draining veins?

ObjectiveOur study aimed to identify predictive factors for malignant post-treatment edema and hemorrhage in patients who underwent microsurgical treatment of arteriovenous malformation (AVM) in our institution. MethodsThe study included 72 patients treated by microsurgery for cerebral symptomatic and/or ruptured AVM between 2010 and 2020. Six patients developed postprocedural malignant edema and hemorrhage (group M); the other 66 patients had no malignant edema and hemorrhage (group NM). In each patient, flow was assessed indirectly by summing the diameters of all feeding arteries to obtain an overall diameter (ODA), and similarly for draining veins (ODV). High-flow was defined as a delay between feeding artery injection and draining vein injection (DAV)<1 second on dynamic digital subtraction angiography. Univariate analysis was performed. ResultsMean ODA and ODV were respectively 11mm (±8.2) and 11mm (±5.3) in group M and 2.9mm (±1.4) and 3.7mm (±1.3) in group NM (P=0.001). High-flow AVM was demonstrated in 4 out of 5 patients (85%) in group M and in 14 out of 55 (25%) in group NM (P=0.02). Associated aneurysm was seen in 5 patients in group M (83%) and in 11 in group NM (17%) (P=0.001). ConclusionHigh-flow AVM may be associated with higher risk of postoperative edema and hemorrhage. Multidisciplinary discussion is mandatory in these cases, to define a pre-therapeutic plan for progressive staged vascular malformation occlusion.

Bow Hunter’s syndrome: an unusual case of bilateral dynamic occlusion of vertebral arteries

A 54-year-old man came to our attention complaining of occasional tinnitus and blurred vision for 2 years, particularly when driving, the symptoms were linked to rightward head rotation. Neurological examination...

Abstract TP92: Dynamic Digital Subtraction Angiography With Rotation of Head and Neck May Serve as Critical Imaging Modality and Temporary Use of Cervical Collar in Addition to Anti-Platelet Therapy May Prevent Stroke in Cases of Acute Cervical Vertebral Artery Dissection (CVAD)

Introduction: The AHA/ASA have published a statement on the CVAD in 2014 in which a variety of imaging modalities that are performed with the head in neutral position are discussed and pharmacological and endovascular treatment of CVAD is reviewed. The authors have performed a prospective study of 12 patients with acute spontaneous CVAD from 2012 to 2019 who developed angiographic worsening stenosis or occlusion of the dissected VA associated with rotation of the head and cervical collar was added to the anti-platelet therapy. Methods: From 2012 to 2019, we performed a prospective study of 12 consecutive patients with spontaneous acute CVAD. We reviewed initial and follow-up clinical data and dynamic catheter cerebral angiogram with the patient’s head and neck in the straight neutral position and the head turned to the right and left beyond 60 degrees. Results: A total of 12 patients (Age 41.8 +/- 9.8; M=8, F=4) presented with acute stroke or TIA due to a total of 12 CVAD at the level of V1 (N=1), V2 (N=2), V3 (N=5), V4 (N= 2), V2-3 (N=2) segments diagnosed by cerebral angiogram. Initial mRS and NIHSS scores on admission were 3 +/-0.5 and 1.5 +/- 1.9, respectively. Dynamic cerebral angiogram performed with the patient’s head in neutral position showed average stenosis of 71.6 % +/- 18.9. Symptomatic occlusion or worsening stenosis of the dissected VA was observed on dynamic cerebral angiogram with rotation of the head to the contra-lateral side in 10 of 12 patients (83%). All patients were treated with daily Aspirin and Plavix for at least 3 months and placed on a cervical collar for 1 month. A follow-up dynamic cerebral angiogram at 1.8 +/- 1.4 months showed resolution of rotational occlusion or worsening stenosis of the VA. Clinical follow-up evaluation at 13.1+/- 10.9 months showed mRS score of 0.9+/- 1.0 and NIHSS score of 0.4 +/- 0.7 with no recurrent stroke. Conclusion: Dynamic cerebral angiogram may be critical in diagnosing rotational occlusion or stenosis of the dissected VA in patients with acute CVAD. Traditional imaging of the head and neck in neutral position may fail to diagnose adverse effect of rotation of the head and neck in these patients. Temporary use of cervical collar to prevent rotation of the head in the acute period of CVAD should be considered.

Magnetic Particle Imaging for High Temporal Resolution Assessment of Aneurysm Hemodynamics.

PurposeThe purpose of this work was to demonstrate the capability of magnetic particle imaging (MPI) to assess the hemodynamics in a realistic 3D aneurysm model obtained by additive manufacturing. MPI was compared with magnetic resonance imaging (MRI) and dynamic digital subtraction angiography (DSA).Materials and MethodsThe aneurysm model was of saccular morphology (7 mm dome height, 5 mm cross-section, 3–4 mm neck, 3.5 mm parent artery diameter) and connected to a peristaltic pump delivering a physiological flow (250 mL/min) and pulsation rate (70/min). High-resolution (4 h long) 4D phase contrast flow quantification (4D pc-fq) MRI was used to directly assess the hemodynamics of the model. Dynamic MPI, MRI, and DSA were performed with contrast agent injections (3 mL volume in 3 s) through a proximally placed catheter.Results and Discussion4D pc-fq measurements showed distinct pulsatile flow velocities (20–80 cm/s) as well as lower flow velocities and a vortex inside the aneurysm. All three dynamic methods (MPI, MRI, and DSA) also showed a clear pulsation pattern as well as delayed contrast agent dynamics within the aneurysm, which is most likely caused by the vortex within the aneurysm. Due to the high temporal resolution of MPI and DSA, it was possible to track the contrast agent bolus through the model and to estimate the average flow velocity (about 60 cm/s), which is in accordance with the 4D pc-fq measurements.ConclusionsThe ionizing radiation free, 4D high resolution MPI method is a very promising tool for imaging and characterization of hemodynamics in human. It carries the possibility of overcoming certain disadvantages of other modalities like considerably lower temporal resolution of dynamic MRI and limited 2D characteristics of DSA. Furthermore, additive manufacturing is the key for translating powerful pre-clinical techniques into the clinic.

Bow hunter's syndrome: the use of dynamic magnetic resonance angiography and intraoperative fluorescent angiography

Bow hunter's syndrome is a diagnosis typically made using dynamic digital subtraction angiography. The authors present the case of a 68-year-old woman who presented with symptoms consistent with bow hunter's syndrome that was accurately diagnosed utilizing noninvasive dynamic MR angiography. The dynamic MR angiogram clearly illustrated unilateral vertebral artery compression upon turning of the head. A subsequent CT of the cervical spine showed a ventral C-1 osteophyte within the foramen. The patient underwent posterior surgical decompression of the left vertebral artery. Sufficient decompression was confirmed using intraoperative fluorescent angiography with the patient's head turned. This case report is the first to illustrate that dynamic MR angiography can be a reliable and less invasive diagnostic tool. It can also be used to confirm sufficient postoperative decompression and monitor for recurrence. Intraoperative fluorescent angiography has been previously used in the evaluation of intracranial and extracranial vascular patency. This report is the first to show that fluorescent angiography can offer rapid and reliable intraoperative evaluation of vertebral artery decompression in bow hunter's syndrome.

Abstract 2225: Vertebral Artery Stenting for the Treatment of Bow Hunter Syndrome: a report of four cases.

Background: Bow Hunter syndrome is a rare condition that results from vertebrobasilar insufficiency secondary to mechanical occlusion or stenosis of the vertebral artery due to head rotation. Traditionally, surgical intervention with C1-C2 fusion or decompression of the vertebral artery was the mainstay of therapy. Endovascular intervention was rarely described for the treatment of bow hunter syndrome. Methods: The neurointerventional database between July 2005 and October 2010 was reviewed for identification of all cases of bow hunter syndrome that were treated with vertebral artery stenting. We report clinical, technical and outcome data on four patients with bow hunter syndrome who were treated with vertebral artery stenting. Results: Vertebral artery stenting was performed in the V2 segment (C2-C6) of the vertebral arteries in all four patients without significant technical difficulties. All patients reported symptomatic relief with minor or no residual stenosis on dynamic digital subtraction angiography. Conclusion: Vertebral artery stenting for the treatment of Bow Hunter syndrome is feasible, safe, and clinically effective. Endovascular techniques might offer an alternative and a minimally invasive therapy for the treatment of bow hunter syndrome. Figure 1 . Case #1. (A) Selective left subclavian angiogram showing the left vertebral artery with head in neutral position. (B) Narrowing of the V2 segment with head turned to the left. (C) Post-stenting of the V1 (origin) and V2 segments with head turned to the left.

Vertebral Artery Stenting for the Treatment of Bow Hunter’s Syndrome: Report of 4 Cases

Bow hunter's syndrome (BHS) is a rare condition resulting from vertebrobasilar insufficiency secondary to mechanical occlusion or stenosis of the vertebral artery (VA) due to head rotation. Traditionally, surgical intervention with C1-C2 fusion or VA decompression was the mainstay of therapy. Endovascular intervention was rarely performed to treat BHS. We reviewed the neurointerventional database from July 2005 to October 2010 to identify all cases of BHS treated with VA stenting. Here we report clinical, technical, and outcome data for 4 patients with BHS who were treated with VA stenting. In all 4 of these patients, stenting was performed in the V2 segment (C2-C6) of the VA without significant technical difficulties. All patients reported symptomatic relief, and only minor or no residual stenosis was detected by dynamic digital subtraction angiography. Our findings indicate that VA stenting for the treatment of BHS is feasible, safe, and clinically effective. Endovascular techniques might offer an alternative, minimally invasive therapy for the treatment of BHS.

Hemodynamic evaluation with dynamic DSA during the treatment of cerebral vasospasm: A retrospective study

Percutaneous transluminal angioplasty (PTA) and super-selective intra-arterial infusion of papaverine have recently been performed for the treatment of cerebral arterial vasospasm, with generally favorable results in patients with delayed symptomatic cerebral vasospasm. We used dynamic digital subtraction angiography (dynamic DSA) to measure local transit time before and after endovascular treatment (EVT) for the treatment of ruptured intracranial aneurysm and delayed symptomatic cerebral vasospasm. Mean transit time (MTT) was measured by dynamic DSA in 19 patients with ruptured intracranial aneurysm and delayed symptomatic cerebral vasospasm and 6 patients without symptomatic cerebral vasospasm (group III) just after surgery, immediately prior to EVT, just after EVT, and in the chronic stage of disease more than 1 month after onset of subarachnoid hemorrhage. EVT included PTA using a silicone nondetachable balloon and/or superselective infusion of 0.2% papaverine. Symptomatic vasospasm occurred between days 7 and 11 after onset of subarachnoid hemorrhage. The MTT just after the onset of neurologic deterioration in these 10 patients with complete neurologic recovery during the chronic stage of disease (group I) and the other 9 patients without complete recovery (group II) were respectively 6.92 +/- 0.42 seconds and 7.66 +/- 0.78 seconds. The latter value was significantly larger than the former (p < 0.02). MTT just after EVT in group II were also significantly greater than the corresponding MTT in group I (p < 0.002). In addition, immediately prior to EVT the MTT in group I and group II was significantly longer than that in group III (p < 0.0001). Functional analysis with dynamic DSA can be used to detect hemodynamic disturbances, and can be used for hemodynamic evaluation during the treatment of symptomatic cerebral vasospasm.

脳血管攣縮に対する診断と治療

In the present study, we report on the hemodynamic mechanism of appearance of hemiparesis after aneurysmal subarachnoid hemorrhage (SAH), usefulness of intracisternally located echography to detect narrowing of the first segment (M1 segment) of the middle cerebral artery, clinical introduction of dynamic digital subtraction angiography (dynamic DSA) to measure local transit time in the territory of spastic intracranial vessels, and finally the clinical results of endovascular treatment using percutaneous transluminal angioplasty and/or papaverine hydrochloride. Appearance of hemiparesis due to delayed vasospasm was thought to be caused by decrease in blood flow in the corona radiata fed by lenticulostriate arteries and medullary arteries of the middle cerebral artery. Intracisternally located echography detected a decrease in inner diameter of M1 segment. When the mean transit time lasted over 5.52 sec just after endovascular treatment for delayed vasospasm, cerebral infarction occurred, resulting in motor and/or cortical deficits. Thirteen (56.5%) of 23 patients endovascularlly treated for delayed vasospasm, resulted in good recovery more than three months after onset of SAH.