Nicholas A Telischak

Arterial spin labeling MRI: clinical applications in the brain.

Visualization of cerebral blood flow (CBF) has become an important part of neuroimaging for a wide range of diseases. Arterial spin labeling (ASL) perfusion magnetic resonance imaging (MRI) sequences are increasingly being used to provide MR‐based CBF quantification without the need for contrast administration, and can be obtained in conjunction with a structural MRI study. ASL MRI is useful for evaluating cerebrovascular disease including arterio‐occlusive disease, vascular shunts, for assessing primary and secondary malignancy, and as a biomarker for neuronal metabolism in other disorders such as seizures and neurodegeneration. In this review we briefly outline the various ASL techniques including advantages and disadvantages of each, methodology for clinical interpretation, and clinical applications with specific examples. J. Magn. Reson. Imaging 2015;41:1165–1180.

Initial experience with SOFIA as an intermediate catheter in mechanical thrombectomy for acute ischemic stroke

Background The benefits of mechanical thrombectomy for emergent large vessel occlusion (ELVO) have been established. Combined mechanical/aspiration (Solumbra) and a direct aspiration as a first pass technique (ADAPT) are valid procedures requiring an intermediate catheter for clot suction. Recently, SOFIA (Soft torqueable catheter Optimized For Intracranial Access) was developed as a single lumen flexible catheter with coil and braid reinforcement, but its suitability for mechanical thrombectomy had not been evaluated. Objective To describe our initial experience with SOFIA in acute stroke intervention and evaluate its efficacy and safety. Methods All patients with ELVO undergoing endovascular stroke intervention with SOFIA were identified. Demographic, presentation, treatment, and complication data were recorded. Primary outcome was Thrombolysis in Cerebral Infarction (TICI) 2b/3 revascularization rate and the number of passes required. Secondary outcomes included complication rates and discharge National Institute of Health Stroke Scale (NIHSS) score. Results 33 patients with a mean age of 72 years were treated for ELVO with SOFIA and IV tissue plasminogen activator was administered in 67%. Vessel occlusion involved the internal carotid artery (15.2%), M1 (48.5%), and M2 (24.2%) segments, and posterior circulation (12.1%). Median presentation NIHSS score was 14 (IQR 11–19) and discharge NIHSS 4 (IQR 2–14). The Solumbra technique represented 94% of treatments and ADAPT 3%. The TICI 2b/3 revascularization rate was 94%, including 48.5% TICI 3 with an average of 1.6 passes. The symptomatic reperfusion hemorrhage rate was 6%. Procedural complications occurred in four patients, but were unrelated to SOFIA. Mortality was 21%, secondary to failed revascularization, hemorrhagic transformation, and baseline medical condition. Conclusions Mechanical and aspiration thrombectomy with SOFIA is safe and effective with high revascularization rates. Its trackability, stability, and luminal size make SOFIA suitable for stroke intervention.

Cerebral vascular findings in PAPA syndrome: cerebral arterial vasculopathy or vasculitis and a posterior cerebral artery dissecting aneurysm

A young patient with PAPA (pyogenic arthritis, pyoderma gangrenosum, and acne) syndrome developed an unusual cerebral arterial vasculopathy/vasculitis (CAV) that resulted in subarachnoid hemorrhage from a ruptured dissecting posterior cerebral artery (PCA) aneurysm. This aneurysm was successfully treated by endovascular coil sacrifice of the affected segment of the PCA. The patient made an excellent recovery with no significant residual neurologic deficit.

Headway Duo microcatheter for cerebral arteriovenous malformation embolization with n-BCA.

Background Cerebral arteriovenous malformations (AVMs) are uncommon vascular lesions, and hemorrhage secondary to AVM rupture results in significant morbidity and mortality. AVMs may be treated by endovascular embolization, and technical advances in microcatheter design are likely to improve the success and safety of endovascular embolization of cerebral AVMs. Objective To describe our early experience with the Headway Duo microcatheter for embolization of cerebral AVMs with n-butyl-cyanoacrylate (n-BCA). Methods Consecutive patients treated by endovascular embolization of a cerebral AVM with n-BCA delivered intra-arterially through the Headway Duo microcatheter (167 cm length) were identified. Patient demographic information, procedural details, and patient outcome were determined from electronic medical records. Results Ten consecutive patients undergoing cerebral AVM embolization using n-BCA injected through the Headway Duo microcatheter were identified. Presenting symptoms included headache, hemorrhage, seizures, and weakness. Spetzler Martin grades ranged from 1 to 5, and AVMs were located in the basal ganglia (2 patients), parietal lobe (4 patients), frontal lobe (1 patient), temporal lobe (1 patient), an entire hemisphere (1 patient), and posterior fossa (1 patient). 50 arterial pedicles were embolized, and all procedures were technically successful. There was one post-procedural hemorrhage that was well tolerated by the patient, and no other complications occurred. Additional AVM treatment was performed by surgery and radiation therapy. Conclusions The Headway Duo microcatheter is safe and effective for embolization of cerebral AVMs using n-BCA. The trackability and high burst pressure of the Headway Duo make it an important and useful tool for the neurointerventionalist during cerebral AVM embolization.

Sofia intermediate catheter and the SNAKE technique: safety and efficacy of the Sofia catheter without guidewire or microcatheter construct

Background Neurointerventional surgeries (NIS) benefit from supportive endovascular constructs. Sofia is a soft-tipped, flexible, braided single lumen intermediate catheter designed for NIS. Sofia advancement from the cervical to the intracranial circulation without a luminal guidewire or microcatheter construct has not been described. Objective To evaluate the efficacy and safety of the new Sofia Non-wire Advancement techniKE (SNAKE) for advancement of the Sofia into the cerebral circulation. Methods Consecutive patients who underwent NIS using Sofia were identified. Patient information, SNAKE use, and patient outcome were determined from electronic medical records. Sofia advancement to the cavernous internal carotid artery or the V2/V3 segment junction of the vertebral artery was the primary outcome measure. Secondary outcomes included arterial vasospasm and arterial dissection. Results 263 Patients (181 females, 69%) who underwent a total of 305 NIS using Sofia were identified. SNAKE (SNAKE+) was used in 187 procedures (61%). Two hundred and ninety-three procedures (96%) were technically successful, which included 184 SNAKE+ NIS and 109 SNAKE− NIS. Primary outcome was achieved in all SNAKE+ procedures, but not in five SNAKE− procedures (2%). No arterial dissections were identified among 305 interventions. In the intracranial circulation, a single SNAKE+ patient (0.5%) had non-flow limiting arterial vasospasm involving the petrous internal carotid. Three SNAKE+ patients (1.6%) and one SNAKE− patient (0.8%) demonstrated external carotid artery branch artery vasospasm during dural arteriovenous fistula or facial arteriovenous malformation treatment. Conclusion SNAKE is a safe and effective technique for Sofia advancement. Sofia is a highly effective and safe intermediate catheter for a variety of NIS.

Patient Outcomes and Cerebral Infarction after Ruptured Anterior Communicating Artery Aneurysm Treatment

BACKGROUND AND PURPOSE: Anterior communicating artery aneurysm rupture and treatment is associated with high rates of dependency, which are more severe after clipping compared with coiling. To determine whether ischemic injury might account for these differences, we characterized cerebral infarction burden, infarction patterns, and patient outcomes after surgical or endovascular treatment of ruptured anterior communicating artery aneurysms. MATERIALS AND METHODS: We performed a retrospective cohort study of consecutive patients with ruptured anterior communicating artery aneurysms. Patient data and neuroimaging studies were reviewed. A propensity score for outcome measures was calculated to account for the nonrandom assignment to treatment. Primary outcome was the frequency of frontal lobe and striatum ischemic injury. Secondary outcomes were patient mortality and clinical outcome at discharge and at 3 months. RESULTS: Coiled patients were older (median, 55 versus 50 years; P = .03), presented with a worse clinical status (60% with Hunt and Hess Score >2 versus 34% in clipped patients; P = .02), had a higher modified Fisher grade (P = .01), and were more likely to present with intraventricular hemorrhage (78% versus 56%; P = .03). Ischemic frontal lobe infarction (OR, 2.9; 95% CI, 1.1–8.4; P = .03) and recurrent artery of Heubner infarction (OR, 20.9; 95% CI, 3.5–403.7; P < .001) were more common in clipped patients. Clipped patients were more likely to be functionally dependent at discharge (OR, 3.2; P = .05) compared with coiled patients. Mortality and clinical outcome at 3 months were similar between coiled and clipped patients. CONCLUSIONS: Frontal lobe and recurrent artery of Heubner infarctions are more common after surgical clipping of ruptured anterior communicating artery aneurysms, and are associated with poorer clinical outcomes at discharge.

Early Cerebral Vein After Endovascular Ischemic Stroke Treatment Predicts Symptomatic Reperfusion Hemorrhage

Background and Purpose— Parenchymal hemorrhage (PH) after endovascular mechanical thrombectomy in acute ischemic stroke leads to worse outcomes. Better clinical and imaging biomarkers of symptomatic reperfusion PH are needed to identify patients at risk. We identified clinical and imaging predictors of reperfusion PH after endovascular mechanical thrombectomy with attention to early cerebral veins (ECVs) on postreperfusion digital subtraction angiography. Methods— We performed a retrospective cohort study of consecutive acute ischemic stroke patients undergoing endovascular mechanical thrombectomy at our neurovascular referral center. Clinical and imaging characteristics were collected from patient health records, and random forest variable importance measures were used to identify predictors of symptomatic PH. Predictors of secondary outcomes, including 90-day mortality, functional dependence (modified Rankin Scale score, >2), and National Institutes of Health Stroke Scale shift, were also determined. Diagnostic test characteristics of ECV for symptomatic PH were determined using a receiver operating characteristic analysis. Differences between patients with and without symptomatic PH were assessed with Fisher exact test and the Wilcoxon rank sum (Mann–Whitney U test) test at the 0.05 significance level. Results— Of 64 patients with anterior circulation large-vessel occlusion identified, 6 (9.4%) developed symptomatic PH. ECV was the strongest predictor of symptomatic PH with more than twice the importance of the next best predictor, male sex. Although ECV was also predictive of 90-day mortality and functional dependence, other characteristics were more important than ECV for these outcomes. The sensitivity and specificity of ECV alone for subsequent hemorrhage were both 0.83, with an area under the curve of 0.83 and 95% confidence interval of 0.66 to 1.00. Conclusions— ECV on postendovascular mechanical thrombectomy digital subtraction angiography is highly diagnostic of subsequent symptomatic reperfusion hemorrhage in this data set. This finding has important implications for post-treatment management of blood pressure and anticoagulation.

Fluoroscopic C-Arm and CT-Guided Selective Radiofrequency Ablation for Trigeminal and Glossopharyngeal Facial Pain Syndromes

Objectives Percutaneous radiofrequency ablation (RFA) of the gasserian ganglion through the foramen ovale and the glossopharyngeal nerve at the jugular foramen is a classical approach to treating trigeminal neuralgia (TN) and glossopharyngeal neuralgia (GPN), respectively. However, it can be technically challenging with serious complications. We have thus developed a novel technique utilizing C-arm and computerized tomography (CT) guidance to block TN and GPN. Our goals were to describe a three-dimensional image-based technique to improve patient comfort and to decrease procedural time associated with needle guidance. Study design Consecutive procedures were reviewed. Setting Academic hospital. Methods Three patients with classical TN and GPN and 15 patients with atypical facial pain (AFP) were treated. Numeric rating scale (NRS) scores for pain at pretreatment and at one, three, and 12 months post-treatment were recorded. The primary clinical outcome (50% or more reduction in NRS) and secondary adverse clinical outcome (hematoma, facial numbness, etc.) were monitored. Results We had a 100% technical success with respect to appropriate needle positioning. All three classical TN/GPN patients had both immediate and sustained pain relief. Complications were minimal. The 15 AFP patients, however, showed more variable results, with only five (33%) having sustained pain relief, while in the other 10 (67%) patients, we observed suboptimal response. Conclusions We present a novel method and single-center experience with C-arm and CT-guided RFA of facial pain. Quick and accurate needle placement will help future advancements in the RFA algorithm so that more durable and consistent effects can be attained, reducing uncertainty with respect to needle placement as a confounder. The RFA procedure in our study had a satisfying effect for classical TN/GPN patients but was less successful for AFP patients, though it did mirror the results from previous studies. Limitations This study is limited by its small sample size and nonrandomized design.

Clinical and Arterial Spin Labeling Brain MRI Features of Transitional Venous Anomalies: Clinical and ASL-MRI Features of Transitional Venous Anomalies

Transitional venous anomalies (TVAs) are rare cerebrovascular lesions that resemble developmental venous anomalies (DVAs), but demonstrate early arteriovenous shunting on digital subtraction angiography (DSA) without the parenchymal nidus of arteriovenous malformations (AVMs). We investigate whether arterial spin labeling (ASL) magnetic resonance imaging (MRI) can distinguish brain TVAs from DVAs and guide their clinical management.

Pipeline embolization device retraction and foreshortening after internal carotid artery blister aneurysm treatment

Background Subarachnoid hemorrhage (SAH) secondary to rupture of a blister aneurysm (BA) results in high morbidity and mortality. Endovascular treatment with the pipeline embolization device (PED) has been described as a new treatment strategy for these lesions. We present the first reported case of PED retraction and foreshortening after treatment of a ruptured internal carotid artery (ICA) BA. Case description A middle-aged patient presented with SAH secondary to ICA BA rupture. The patient was treated with telescoping PED placement across the BA. After 5 days from treatment, the patient developed a new SAH due to re-rupture of the BA. Digital subtraction angiography revealed an increase in caliber of the supraclinoid ICA with associated retraction and foreshortening of the PED that resulted in aneurysm uncovering and growth. Conclusions PED should be oversized during ruptured BA treatment to prevent device retraction and aneurysm regrowth. Frequent imaging follow up after BA treatment with PED is warranted to ensure aneurysm occlusion.