Sorenson, Thomas J.

Abstract Herein, we demonstrate a case of a large, wide-necked, basilar apex aneurysm (BAA) that was treated with neck reconstruction-assisted coil embolization using the PulseRider device (PulsarVascular, Los Gatos, California), a novel neck-reconstruction device. A 68-yr-old man was found to have large BAA during work-up for sinusitis. Computed tomography angiogram revealed an 11 × 10-mm BAA. Patient has history of coronary artery disease, atrial fibrillation (currently taking Warfarin), recent left hip replacement and right femoral bypass. Treatment of the aneurysm was advised due to its location and size. Microsurgical clip reconstruction was high risk for general anesthesia due to his medical comorbidities and anticoagulation. Wide-necked bifurcation aneurysms are challenging to treat with traditional balloon- or stent-assisted techniques. To mitigate these challenges, novel neck-reconstruction devices have been developed. The Pulsar is one of these neck-reconstruction devices that removes the need to selectively catheterize branch arteries; it is available in a “Y” and “T” configuration. Under conscious sedation and through a radial artery approach, the patient underwent endovascular reconstruction of BAA with Pulsar device and coils. A 6-Fr guide catheter, a 0.021" microcatheter for the Pulsar device and a 0.017" microcatheter for coil delivering were used. A 3 × 8.6 mm Pulsar device was selected based on aneurysm neck and basilar artery measurements. Complete embolization (Raymond-Roy 1 obliteration) of the aneurysm was successfully achieved with no complications. The patient remained neurologically intact and was discharged on postoperative day 1. Parts of this video were published in Intracranial Aneurysms (1st Edition), Ringer (Ed), online companion to chapter 33B, Copyright Elsevier (2018).

OBJECTIVECavernous internal carotid artery (ICA) aneurysms are frequently diagnosed incidentally and the benign natural history of these lesions is well known, but there is limited information assessing the risk of growth in untreated patients. The authors sought to assess and analyze risk factors in patients with cavernous ICA aneurysms and compare them to those of patients with intracranial berry aneurysms in other locations.METHODSData from consecutive patients who were diagnosed with a cavernous ICA aneurysm were retrospectively reviewed. The authors evaluated patients for the incidence of cavernous ICA aneurysm growth and rupture. In addition, the authors analyzed risk factors for cavernous ICA aneurysm growth and compared them to risk factors in a population of patients diagnosed with intracranial berry aneurysms in locations other than the cavernous ICA during the same period.RESULTSIn 194 patients with 208 cavernous ICA aneurysms, the authors found a high risk of aneurysm growth (19.2% per patient-year) in patients with large/giant aneurysms. Size was significantly associated with higher risk of growth. Compared to patients with intracranial berry aneurysms in other locations, patients with cavernous ICA aneurysms were significantly more likely to be female and have a lower incidence of hypertension.CONCLUSIONSAneurysms of the cavernous ICA are benign lesions with a negligible risk of rupture but a definite risk of growth. Aneurysm size was found to be associated with aneurysm growth, which can be associated with new onset of symptoms. Serial follow-up imaging of a cavernous ICA aneurysm might be indicated to monitor for asymptomatic growth, especially in patients with larger lesions.

OBJECTIVEConcomitant unruptured intracranial aneurysms (UIAs) are present in patients with carotid artery stenosis not infrequently and result in unique management challenges. Thus, we investigated the risk of rupture of an aneurysm after revascularization of a carotid artery in a contemporary consecutive series of patients seen at our institution.METHODSData from patients who underwent a carotid revascularization in the presence of at least one concomitant UIA at our institution from 1991 to 2018 were retrospectively reviewed. Patients were evaluated for the incidence of aneurysm rupture within 30 days (early period) and after 30 days (late period) of carotid revascularization, as well as for the incidence of periprocedural complications from the treatment of carotid stenosis and/or UIA.RESULTSOur study included 53 patients with 63 concomitant UIAs. There was no rupture within 30 days of carotid revascularization. The overall risk of rupture was 0.87% per patient-year. Treatment (coiling or clipping) of a concomitant UIA, if pursued, could be performed successfully after carotid revascularization.CONCLUSIONSCarotid artery revascularization in the setting of a concomitant UIA can be performed safely without an increased 30-day or late-term risk of rupture. If indicated, treatment of the UIA can take place after the patient recovers from the carotid procedure.

Cerebral protection device utilization during carotid artery stenting (CAS) has been demonstrated to decrease the risk of perioperative stroke. The ProximAl Protection with the MO.MA Device During CaRotid Stenting (ARMOUR) Trial had the lowest event rates of any independently adjudicated study. In this video of two cases of severe carotid artery stenosis, the authors present the nuances of the CAS procedure utilizing a dual-balloon guide catheter device (MO.MA). This device has the benefit of being in place before the lesion is crossed with any device, being able to arrest flow while the atherosclerotic lesion is crossed, and aiding in protection from distal emboli and stroke. The video can be found here: https://youtu.be/0o8DlC1n6_M .

Abstract Cavernous malformations (CM) of the anterior midbrain are best reached through an orbitozygomatic (OZ) approach with removal of the orbital rim and wide Sylvian fissure dissection. Our surgical video demonstrates this approach to resect a ruptured CM in a 36-yr-old woman who presented with headaches, left face and left arm paresthesias/weakness, and right-sided partial oculomotor nerve (CN III) palsy. Initial magnetic resonance imaging (MRI) showed a midbrain CM, and the patient was managed conservatively. However, 1 wk later, she presented again with worsened left arm and leg weakness and complete CN III palsy. Seven Tesla MRI demonstrated a larger hematoma, and the CM with new mass effect and upper pons extension. The patient underwent a right modified OZ craniotomy and Sylvian fissure split under guidance of intraoperative neuronavigation and with neuromonitoring. The carotid-oculomotor triangle and the Liliequist membrane were dissected to access the midbrain, and CN III was identified and followed posteriorly to the midbrain. Confirmed with neuronavigation, a longitudinal incision of the midbrain was performed, and the CM was encountered. The hematoma and CM were debulked and removed in a piece-meal fashion, leaving hemosiderin-stained brain intact to prevent unnecessary additional damage to the midbrain. Postoperative MRI confirmed gross-total resection, and the patient's weakness recovered substantially. In this video, we demonstrate that the brainstem is no longer forbidden surgical territory, and show how the use of neuronavigation for surgical planning, positioning, and approach, in addition to the understanding of safe entry zones and meticulous microsurgical technique have made safe and effective surgery on the brainstem possible.

Abstract Perimedullary fistulae of the spinal cord are rare vascular lesions that can present with different clinical patterns: hemorrhage, progressive myelopathy due to arterial steal and/or venous congestion, or symptoms due to compression of neural structures by engorged vessels. Treatment consists of surgical excision, endovascular embolization, or a combination of the two. If complete obliteration of the nidus exposes the patient to undue risk of permanent neurological deficits, incomplete obliteration with reduction of the vascular supply is a reasonable compromise to improve clinical symptomatology. Partial devascularization may also alter the natural history by decreasing the risk of further growth and bleeding. In this video we illustrate the case of a patient with a perimedullary fistula of the conus treated with surgical disconnection of the main fistulous component. Partial devascularization resulted in resolution of MRI signal changes and symptoms with documented good clinical and radiological outcome and progressive regression of the residual nidus over six years of follow-up.

Abstract While revascularization of the acutely or chronically occluded internal carotid artery has become commonplace with modern endovascular techniques, revascularization of an acutely occluded common carotid artery (CCA) is a controversial procedure with unique challenges. These challenges can be related to the lack of observable markers for identifying vessels during navigation or for identifying the exact location and extent of occlusion within the CCA, in addition to wide-ranging treatment risks. In this video, we illustrate the controversial revascularization of a 68-yr-old woman with an acute CCA occlusion who presented with fluctuating neurological symptoms. We believed treatment to be indicated by the lack of adequate collaterals on the intracranial CTA, and fluctuating symptoms in the absence of an intracranial major vessel occlusion, suggesting that the CCA occlusion was exerting important hemodynamic effects and at risk of causing a major stroke without revascularization, despite a low initial NIH stroke score. Though acute recanalization of patients with low NIH stroke score with stent-angioplasty is a controversial procedure, we believed it to be necessary in the case of our patient and believe it will likely be the focus of the next wave of large clinical trials dedicated to acute stroke.

Incidental vascular lesions are being discovered at an increasing frequency due to widespread noninvasive brain imaging studies. One of these lesions has recently been termed a “pure arterial malformation” (PAM), which is defined as dilated, overlapping, and tortuous arteries forming a mass of arterial loops with a coil-like appearance in the absence of arteriovenous shunting. The pathogenesis of these lesions is not known, but a congenital etiology is suspected. The authors report the case of a 17-year-old female who was found to have a PAM of the posterior inferior cerebellar artery with adipose tissue interspersed within the arterial loops. The authors believe that this abnormal intracranial association between blood vessel and adipose tissue lends further support to the theory that PAMs are the result of a congenital malformation and are therefore safe to manage conservatively given their presumed benign natural history. Far from offering conclusive evidence, this unique case report adds to the growing body of PAM literature and strengthens an increasingly supported congenital theory of genesis.

Abstract Cavernous malformations of the third ventricle are uncommon vascular lesions. Evidence suggests that cavernous malformations in this location might have a more aggressive natural history due to their risk of intraventricular hemorrhage and hydrocephalus. 1 The gold standard of treatment is considered to be microsurgical gross total resection of the lesion. However, with progressive improvement in endoscopic capabilities, several authors have recently advocated for the role of minimally-invasive neuroendoscopy for resecting intraventricular cavernous malformations. 2-4 In this timely intraoperative video, we demonstrate the gross total resection of a third ventricle cavernous malformation that presented with hemorrhage via a right-sided trans-frontal neuroendoscopic approach.

Abstract Middle cerebral artery (MCA) aneurysms often have an irregular morphology that might require creative clipping techniques even in the case of small aneurysms. In this video, we illustrate the case of a patient with an incidental but very irregular MCA aneurysm. The presence of 2 separate, asymmetric lobes was dealt with by utilizing the “interlocking” clip technique in which a regular clip is used to obliterate 1 portion of the aneurysm and a fenestrated clip, with the ring of the fenestration circling the body of the first clip, is used to obtain obliteration of the other lobe. This patient also had a contralateral internal carotid artery occlusion, and we discuss the pitfalls of temporary clipping in such a situation.