Citations

Background Although rare, spinal arteriovenous malformations (AVMs) are thought to be more prevalent in the hereditary Hereditary Hemorrhagic Telangiectasia (HHT) population. Methods We report a case of a spinal AVM in a 37-year-old female with HHT treated with endovascular embolization. In addition, we report findings from a systematic review of the literature on the clinical characteristics, angioarchitecture, and clinical outcomes of HHT patients with spinal AVMs. Results The patient is a 37 year-old female with definite HHT who presented with a one-year history of progressive gait difficulty. The spinal fistula was incidentally detected on chest computed tomography (CT). Spinal angiography demonstrated a large perimedullary arteriovenous fistula was supplied by a posterolateral spinal artery. The fistula was treated with detachable coils. The patient made a complete neurological recovery. Our systematic review yielded 25 additional cases of spinal AVMs in HHT patients. All fistulae were perimedullary (100.0%). Treatments were described in 24 of the 26 lesions. Endovascular-only treatment was performed in 16 cases (66.6%) and surgical-only treatment was performed in five cases (20.8%). Complete or near-complete occlusion rates were 86.7% (13/15) for endovascular treated cases, 100.0% (4/4) for surgery and 66.6% (2/3) for combined treatments. Overall, 80.0% of patients (16/20) reported improvement in function following treatment, 100.0% (5/5) in the surgery group and 84.6% (11/13) reported improvement in the endovascular group. Conclusions Spinal fistulae in HHT patients are usually type IV perimedullary fistulae. Both endovascular and surgical treatments appeared to be effective in treating these lesions. However, it is clear that endovascular therapy has become the preferred treatment modality.

Spinal epidural arteriovenous fistulas (SEDAVFs) are rare complex lesions often presenting with protean clinical manifestations secondary to compressive symptoms or congestive myelopathy. The imaging manifestations of SEDAVFs on MR angiography/MRI include high T2 signal in the spinal cord, vascular engorgement of the epidural space, and prominent intradural vascular flow voids. Given the complexity of these lesions, they are best characterized anatomically on catheter angiography where careful inspection of arterial feeders and venous drainage patterns can be performed. The imaging hallmark of an SEDAVF on angiography is the presence of a dilated epidural venous pouch through which spinal and paraspinal veins are secondarily opacified. In the lower thoracic and lumbar spine, SEDAVFs are usually located in the ventral epidural space and fed mainly by the anteriorly coursing epidural arteries. In the cervical and upper thoracic spine, SEDAVFs and their feeding arteries are more typically located laterally in the spinal canal. Current treatment options include transarterial or transvenous endovascular embolization with liquid embolic agents or coils, and surgical resection/disconnection of the fistula. Further research is needed to better characterize how and why these lesions form and to identify the best treatment modalities.

OBJECT Flow-diversion treatment has been shown to be associated with high rates of angiographic obliteration; however, the treatment is relatively contraindicated in the acute phase following subarachnoid hemorrhage (SAH) as these patients require periprocedural dual antiplatelet therapy. Acute coiling followed by flow diversion has emerged as an intriguing and feasible treatment option for ruptured complex and giant aneurysms. In this study the authors report outcomes and complications of patients with ruptured aneurysms undergoing coiling in the acute phase followed by planned delayed flow diversion. METHODS This case series includes patients from 2 institutions. All patients underwent standard endovascular coiling in the acute phase after SAH with the intention and plan to proceed with flow diversion at a later date. Outcomes studied included angiographic occlusion, procedure-related complications, and long-term clinical outcome as measured using the modified Rankin Scale. RESULTS A total of 31 patients underwent coiling in the acute phase with the intention to undergo flow diversion at a later date. The mean aneurysm size was 15.8 ± 7.9 mm. Of the 31 patients undergoing coiling, 4 patients could not undergo further flow-diverter therapy: 3 patients (9.7%) died of complications of subarachnoid hemorrhage and 1 patient had permanent morbidity as a result of perioperative ischemic stroke (3.1%). Twenty-seven patients underwent staged placement of flow diverters after adequate recovery. The median time to treatment was 16 weeks. There was one case of aneurysm rebleeding following coil treatment. There were no cases of permanent morbidity or mortality resulting from flow-diverter treatment. Twenty-four patients underwent imaging follow-up; 18 of these patients had aneurysms that were completely or nearly completely occluded (58.1% on an intent-to-treat basis). At last follow-up (mean 18.3 months), 25 patients had mRS scores ≤ 2 (80.6% on an intent-to-treat basis). CONCLUSIONS Staged treatment of ruptured complex and giant intracranial aneurysms with coiling in the acute phase and flow-diverter treatment following recovery from SAH is both safe and effective. In this series, no cases of rebleeding occurred during the interval between coiling and flow diversion. This strategy should be considered as a valid option in patients presenting with these challenging ruptured aneurysms.

Abstract The progressive establishment of endovascular management in treating intracranial aneurysms had lead to continuous technique advancements and development of innovative technologies. Flow diverters are “stent-like” devices currently used for complex unruptured aneurysms allowing endoluminal reconstruction of the parent artery and occlusion of the aneurysm sac. In the present article, we review the development of flow diversion devices through in vitro and in vivo studies to clinical practice and summarize recent clinical data.

Nonhemorrhagic neurological deficits are underrecognized symptoms of intracranial dural arteriovenous fistulas (dAVFs) having cortical venous drainage. These symptoms are the consequence of cortical venous hypertension and portend a clinical course with increased risk of neurological morbidity and mortality. One rarely documented and easily misinterpreted type of nonhemorrhagic neurological deficit is progressive dementia, which can result from venous hypertension in the cortex or in bilateral thalami. The latter, which is due to dAVF drainage into the deep venous system, is the less common of these 2 dementia syndromes. Herein, the authors report 4 cases of dAVF with venous drainage into the vein of Galen causing bithalamic edema and rapidly progressive dementia. Two patients were treated successfully with endovascular embolization, and the other 2 patients were treated successfully with endovascular embolization followed by surgery. The radiographic abnormalities and presenting symptoms rapidly resolved after dAVF obliteration in all 4 cases. Detailed descriptions of these 4 cases are presented along with a critical review of 15 previously reported cases. In our analysis of these 19 published cases, the following were emphasized: 1) the clinical and radiographic differences between dAVF-induced thalamic versus cortical dementia syndromes; 2) the differential diagnosis and necessary radiographic workup for patients presenting with a rapidly progressive thalamic dementia syndrome; 3) the frequency at which delays in diagnosis occurred and potentially dangerous and avoidable diagnostic procedures were used; and 4) the rapidity and completeness of symptom resolution following dAVF treatment.

OBJECT The association between age and outcomes following aneurysm treatment with flow diverters such as the Pipeline Embolization Device (PED) have not been well established. Using the International Retrospective Study of the Pipeline Embolization Device (IntrePED) registry, the authors assessed the age-related clinical outcomes of patients undergoing aneurysm embolization with the PED. METHODS Patients with unruptured aneurysms in the IntrePED registry were divided into 4 age groups: ≤ 50, 51–60, 61–70, and > 70 years old. The rates of the following postoperative complications were compared between age groups using chi-square tests: spontaneous rupture, intracranial hemorrhage (ICH), ischemic stroke, parent artery stenosis, cranial neuropathy, neurological morbidity, neurological mortality, combined neurological morbidity and mortality, and all-cause mortality. The association between age and these complications was tested in a multivariate logistic regression analysis adjusted for sex, number of PEDs, and aneurysm size, location, and type. RESULTS Seven hundred eleven patients with 820 unruptured aneurysms were included in this study. Univariate analysis demonstrated no significant difference in ICH rates across age groups (lowest 1.0% for patients ≤ 50 years old and highest 5.0% for patients > 70 years old, p = 0.097). There was no difference in ischemic stroke rates (lowest 3.6% for patients ≤ 50 years old and highest 6.0% for patients 50–60 years old, p = 0.73). Age > 70 years old was associated with higher rates of neurological mortality; patients > 70 years old had neurological mortality rates of 7.4% compared with 3.3% for patients 61–70 years old, 2.7% for patients 51–60 years old, and 0.5% for patients ≤ 50 years old (p = 0.006). On multivariate logistic regression analysis, increasing age was associated with higher odds of combined neurological morbidity and mortality (odds ratio 1.02, 95% confidence interval 1.00–1.05; p = 0.03). CONCLUSIONS Increasing age is associated with higher neurological morbidity and mortality after Pipeline embolization of intracranial aneurysms. However, the overall complication rates of PED treatment in this group of highly selected elderly patients (> 70 years) were acceptably low, suggesting that age alone should not be considered an exclusion criterion when considering treatment of intracranial aneurysms with the PED.

Carotid artery stenosis is a well-established risk factor of ischemic stroke, contributing to up to 10%-20% of strokes or transient ischemic attacks. Many clinical trials over the last 20 years have used measurements of carotid artery stenosis as a means to risk stratify patients. However, with improvements in vascular imaging techniques such as CT angiography and MR angiography, ultrasonography, and PET/CT, it is now possible to risk stratify patients, not just on the degree of carotid artery stenosis but also on how vulnerable the plaque is to rupture, resulting in ischemic stroke. These imaging techniques are ushering in an emerging paradigm shift that allows for risk stratifications based on the presence of imaging features such as intraplaque hemorrhage (IPH), plaque ulceration, plaque neovascularity, fibrous cap thickness, and presence of a lipid-rich necrotic core (LRNC). It is important for the neurosurgeon to be aware of these new imaging techniques that allow for improved patient risk stratification and outcomes. For example, a patient with a low-grade stenosis but an ulcerated plaque may benefit more from a revascularization procedure than a patient with a stable 70% asymptomatic stenosis with a thick fibrous cap. This review summarizes the current state-of-the-art advances in carotid plaque imaging. Currently, MRI is the gold standard in carotid plaque imaging, with its high resolution and high sensitivity for identifying IPH, ulceration, LRNC, and inflammation. However, MRI is limited due to time constraints. CT also allows for high-resolution imaging and can accurately detect ulceration and calcification, but cannot reliably differentiate LRNC from IPH. PET/CT is an effective technique to identify active inflammation within the plaque, but it does not allow for assessment of anatomy, ulceration, IPH, or LRNC. Ultrasonography, with the aid of contrast enhancement, is a cost-effective technique to assess plaque morphology and characteristics, but it is limited in sensitivity and specificity for detecting LRNC, plaque hemorrhage, and ulceration compared with MRI. Also summarized is how these advanced imaging techniques are being used in clinical practice to risk stratify patients with low- and high-grade carotid artery stenosis. For example, identification of IPH on MRI in patients with low-grade carotid artery stenosis is a risk factor for failure of medical therapy, and studies have shown that such patients may fair better with carotid endarterectomy (CEA). MR plaque imaging has also been found to be useful in identifying revascularization candidates who would be better candidates for CEA than carotid artery stenting (CAS), as high intraplaque signal on time of flight imaging is associated with vulnerable plaque and increased rates of adverse events in patients undergoing CAS but not CEA.

OBJECT Vasopressor-induced hypertension (VIH) is an established treatment for patients with aneurysmal subarachnoid hemorrhage (SAH) who develop vasospasm and delayed cerebral ischemia (DCI). However, the safety of VIH in patients with coincident, unruptured, unprotected intracranial aneurysms is uncertain. METHODS This retrospective multiinstitutional study identified 1) patients with aneurysmal SAH and 1 or more unruptured, unprotected aneurysms who required VIH therapy (VIH group), and 2) patients with aneurysmal SAH and 1 or more unruptured, unprotected aneurysms who did not require VIH therapy (non-VIH group). All patients had previously undergone surgical or endovascular treatment for the presumed ruptured aneurysm. Comparisons between the VIH and non-VIH patients were made in terms of the patient characteristics, clinical and radiographic severity of SAH, total number of aneurysms, number of ruptured/unruptured aneurysms, aneurysm location/size, number of unruptured and unprotected aneurysms during VIH, severity of vasospasm, degree of hypervolemia, and degree and duration of VIH therapy. RESULTS For the VIH group (n = 176), 484 aneurysms were diagnosed, 231 aneurysms were treated, and 253 unruptured aneurysms were left unprotected during 1293 total days of VIH therapy (5.12 total years of VIH therapy for unruptured, unprotected aneurysms). For the non-VIH group (n = 73), 207 aneurysms were diagnosed, 93 aneurysms were treated, and 114 unruptured aneurysms were left unprotected. For the VIH and non-VIH groups, the mean sizes of the ruptured (7.2 ± 0.3 vs 7.8 ± 0.6 mm, respectively; p = 0.27) and unruptured (3.4 ± 0.2 vs 3.2 ± 0.2 mm, respectively; p = 0.40) aneurysms did not differ. The authors observed 1 new SAH from a previously unruptured, unprotected aneurysm in each group (1 of 176 vs 1 of 73 patients; p = 0.50). Baseline patient characteristics and comorbidities were similar between groups. While the degree of hypervolemia was similar between the VIH and non-VIH patients (fluid balance over the first 10 days of therapy: 3146.2 ± 296.4 vs 2910.5 ± 450.7 ml, respectively; p = 0.67), VIH resulted in a significant increase in mean arterial pressure (mean increase over the first 10 days of therapy relative to baseline: 125.1% ± 1.0% vs 98.2% ± 1.2%, respectively; p < 0.01) and systolic blood pressure (125.6% ± 1.1% vs. 104.1% ± 5.2%, respectively; p < 0.01). CONCLUSIONS For small, unruptured, unprotected intracranial aneurysms in SAH patients, the frequency of aneurysm rupture during VIH therapy is rare. The authors do not recommend withholding VIH therapy from these patients.