Thomas P. Madaelil

Percutaneous Image-Guided Cryoablation of Musculoskeletal Metastases: Pain Palliation and Local Tumor Control.

PURPOSE To evaluate the safety and effectiveness of cryoablation of musculoskeletal metastases in terms of achieving pain palliation and local tumor control. MATERIALS AND METHODS A retrospective review was performed of 92 musculoskeletal metastases in 56 patients treated with percutaneous image-guided cryoablation. Mean age of the cohort was 53.9 y ± 15.1, and cohort included 48% (27/56) men. Median tumor volume was 13.0 cm3 (range, 0.5-577.2 cm3). Indications for treatment included pain palliation (41%; 38/92), local tumor control (15%; 14/92), or both (43%; 40/92). Concurrent cementoplasty was performed after 28% (26/92) of treatments. RESULTS In 78 tumors treated for pain palliation, median pain score before treatment was 8.0. Decreased median pain scores were reported 1 day (6.0; P < .001, n = 62), 1 week (5.0; P < .001, n = 70), 1 month (5.0; P < .001, n = 63), and 3 months (4.5; P = .01, n = 28) after treatment. The median pain score at 6-month follow-up was 7.5 (P = .33, n = 11). Radiographic local tumor control rates were 90% (37/41) at 3 months, 86% (32/37) at 6 months, and 79% (26/33) at 12 months after treatment. The procedural complication rate was 4.3% (4/92). The 3 major complications included 2 cases of hemothorax and 1 transient foot drop. CONCLUSIONS Cryoablation is an effective treatment for palliating painful musculoskeletal metastases and achieving local tumor control.

Endovascular parent vessel sacrifice in ruptured dissecting vertebral and posterior inferior cerebellar artery aneurysms: clinical outcomes and review of the literature

Background Ruptured intracranial dissecting aneurysms must be secured quickly to prevent re-hemorrhage. Endovascular sacrifice of the diseased segment is a well-established treatment method, however postoperative outcomes of symptomatic stroke and re-hemorrhage rates are not well reported, particularly for the perforator-rich distal vertebral artery or proximal posterior inferior cerebellar artery (PICA). Methods We retrospectively reviewed cases of ruptured distal vertebral artery or PICA dissecting aneurysms that underwent endovascular treatment. Diagnosis was based on the presence of subarachnoid hemorrhage on initial CT imaging and of a dissecting aneurysm on catheter angiography. Patients with vertebral artery aneurysms were selected for coil embolization of the diseased arterial segment based on the adequacy of flow to the basilar artery from the contralateral vertebral artery. Patients with PICA aneurysms were generally treated only if they were poor surgical candidates. Outcomes included symptomatic and asymptomatic procedure-related cerebral infarction, recurrent aneurysm rupture, angiographic aneurysm recurrence, and estimated modified Rankin Scale (mRS). Results During the study period, 12 patients with dissecting aneurysms involving the distal vertebral artery (n=10) or PICA (n=2) were treated with endovascular sacrifice. Two patients suffered an ischemic infarction, one of whom was symptomatic (8.3%). One patient (8.3%) died prior to hospital discharge. No aneurysm recurrence was identified on follow-up imaging. Ten patients (83%) made a good recovery (mRS ≤2). Median clinical and imaging follow-up periods were 41.7 months (range 0–126.4 months) and 14.3 months (range 0.03–88.6 months), respectively. Conclusions In patients with good collateral circulation, endovascular sacrifice may be the preferred treatment for acutely ruptured dissecting aneurysms involving the distal vertebral artery.

Mechanical thrombectomy in pediatric acute ischemic stroke: Clinical outcomes and literature review

There are limited data on outcomes of mechanical thrombectomy for pediatric stroke using modern devices. In this study, we report two cases of pediatric acute ischemic stroke treated with mechanical thrombectomy, both with good angiographic result (TICI 3) and clinical outcome (no neurological deficits at 90 days). In addition, we conducted a literature review of all previously reported cases describing the use of modern thrombectomy devices. Including our two cases, the aggregate rate of partial or complete vessel recanalization was 100% (22/22), and the aggregate rate of favorable clinical outcome was 91% (20/22). This preliminary evidence suggests that mechanical thrombectomy with modern devices may be a safe and effective treatment option in pediatric patients with acute ischemic stroke.

Drill-Assisted Biopsy of the Axial and Appendicular Skeleton: Safety, Technical Success, and Diagnostic Efficacy

The purpose of this study was to evaluate the safety, technical success rate, and diagnostic efficacy of drill-assisted axial and appendicular bone biopsies. During a 3-y period, 703 drill-assisted biopsies were performed. The cohort included 54.2% men, with a mean age of 57.6 y ± 17.1. Median lesion volume was 10.9 mL (interquartile range, 3.4-30.2 mL). Lesions were lytic (31.7%), sclerotic (21.2%), mixed lytic and sclerotic (27.7%), or normal radiographic bone quality (19.3%). No complications were reported. The technical biopsy success rate was 99.9%. Crush artifact was present in 5.8% of specimens submitted for surgical pathologic examination, and 2.1% of specimens were inadequate for histologic evaluation.

Intra-arterial versus intravenous abciximab therapy for thromboembolic complications of neuroendovascular procedures: case review and meta-analysis

Background Abciximab is used to treat thromboembolic complications of neuroendovascular procedures, but outcomes of treatment are not well defined. Objective To examine the angiographic and clinical outcomes based on route of abciximab administration and degree of vessel recanalization. Materials and methods A prospectively maintained database of neuroendovascular procedures performed between January 2004 and May 2015 was retrospectively reviewed to identify cases with thromboembolic complications treated with abciximab. In these cases, route of administration, degree of vessel recanalization, and presence or absence of infarction were determined. A meta-analysis of similar cases in the literature was also performed. Results Abciximab was administered in 0.24% (47 of 19 566) of procedures to treat thromboemboli in 59 vessels. Angiographic improvement was seen in 94% after IA therapy and 79% after IV therapy (p=0.133). In our meta-analysis of 391 treated patients, angiographic improvement was greater after IA (91.7%) than IV (77.4%) treatment (p<0.001). Postprocedural infarction occurred more frequently with distal lesions (42%) than local lesions (12%) (p=0.014), and occlusive lesions (36%) than non-occlusive lesions (4.8%) (p=0.010). Infarction was significantly less common with complete angiographic resolution (0%) than with partial or no improvement (54%) (p<0.001). Symptomatic intracranial hemorrhage occurred in 2.1%. Conclusions Abciximab produces a high rate of angiographic improvement and a low incidence of postprocedural infarct in neuroendovascular procedures complicated by thromboemboli. IA abciximab produces greater angiographic improvement than IV treatment. Postprocedural infarction is less common in patients with complete angiographic response than in those with partial or no response.

Treatment of osseous metastases using the Spinal Tumor Ablation with Radiofrequency (STAR) system

ABSTRACT Introduction: Percutaneous ablation is an emerging, minimally invasive therapy for patients with osseous metastases who have not responded or have contraindications to radiation therapy. Goals of therapy are pain relief, and in some cases, prevention of local tumor progression. Areas covered: The epidemiology, pathophysiology, natural history, and traditional management of metastatic bone disease are reviewed. Novel features of the Spinal Tumor Ablation with Radiofrequency (STAR) System (DFINE, San Jose, CA) that facilitate treatment of osseous metastases are described, including the bipolar electrode, extensible distal tip that can be curved up to 90°, and inclusion of thermocouples that enable real-time monitoring of the ablation zone volume. Lastly, research evaluating the safety and efficacy of using this device to treat musculoskeletal metastases is summarized. Expert commentary: Although evidence supporting the efficacy of RFA for the treatment of bone metastases is limited to case series, it is a reasonable therapy when other options have been exhausted, especially given the safety and minimal morbidity of the procedure. The STAR Tumor Ablation System has expanded the anatomic scope of bone metastases that can be safely and effectively treated with percutaneous ablation.

Posterior reversible encephalopathy syndrome with thalamic involvement during vasopressor treatment of vertebrobasilar vasospasm after subarachnoid hemorrhage

Hemodynamic augmentation is the primary medical intervention employed to reverse neurological deficits associated with vasospasm and delayed cerebral ischemia following aneurysmal subarachnoid hemorrhage. Failure to improve despite induced hypertension (IH) may raise concern for persistent hypoperfusion and prompt even more aggressive blood pressure augmentation. However, posterior reversible encephalopathy syndrome (PRES) is a hyperperfusion syndrome reported as a rare complication of IH that may confound this picture. We report a case of PRES with prominent thalamic involvement and impaired level of consciousness secondary to blood pressure augmentation for the treatment of symptomatic vertebrobasilar vasospasm. Recognition of this syndrome in distinction to worsening ischemia is particularly critical, as normalization of blood pressure should lead to rapid clinical improvement.

Treatment of pediatric intracranial aneurysms: case series and meta-analysis

Background There are limited outcome data to guide the choice of treatment in pediatric patients with cerebral aneurysms. Objective To describe our institutional experience treating pediatric patients with cerebral aneurysms and to conduct a meta-analysis of available studies to provide the best current evidence on treatment related outcomes. Methods We identified pediatric patients with cerebral aneurysms evaluated or treated at our institution using a comprehensive case log. We also identified studies to include in a meta-analysis through a systematic search of Pubmed, SCOPUS, EMBASE, and the Cochrane Database of Systematic Reviews. As part of both the local analysis and meta-analysis, we recorded patient characteristics, aneurysm characteristics, management, and outcomes. Statistical analysis was performed using Fisher’s exact test and the two tailed Student’s t test, as appropriate. Results 42 pediatric patients with 57 aneurysms were evaluated at our institution, and treatment specific outcome data were available in 560 patients as part of our meta-analysis. Endovascular and surgical treatments yielded comparable rates of favorable outcome in all children (88.3% vs 82.7%, respectively, P=0.097), in children with ruptured aneurysms (75% vs 83%, respectively, P=0.357), and in children with unruptured aneurysms (96% vs 97%, respectively, P=1.000). Conclusion Endovascular and surgical treatment yield comparable long term clinical outcomes in pediatric patients with cerebral aneurysms.

Preoperative Fiducial Marker Placement in the Thoracic Spine: A Technical Report

Study Design. A retrospective review. Objective. The aim of this study was to demonstrate proof-of-concept of preoperative percutaneous intraosseous fiducial marker placement before thoracic spine surgery. Summary of Background Data. Wrong-level spine surgery is defined as a never event by Center for Medicare Services, yet the strength of data supporting the implementation of Universal Protocol to limit wrong level surgery is weak. The thoracic spine is especially prone to intraoperative mislocalization, particularly in cases of morbid obesity and anatomic variations. Methods. We retrospectively reviewed all cases of preoperative percutaneous image-guided intraosseous placement of a metallic marker in the thoracic spine. Indications for surgery included degenerative disc disease (16/19), osteochondroma resection, spinal metastasis, and ligation of dural arteriovenous malformation. All metallic markers were placed from a percutaneous transpedicular approach under imaging guidance [fluoroscopy and computed tomography (CT) or CT alone]. Patient body mass index (BMI) was recorded. Overweight and obese BMI was defined greater than 25 and 30 kg/m2, respectively. Results. All 19 patients underwent fiducial marker placement and intraoperative localization successfully without complication. Twenty-two thoracic spine levels were localized. The T7, T9, T10, and T11 levels were the most often localized at rate of 18.1% for each level (4/22). The most cranial and caudal levels localized were T4 and T11. About 84.2% (16/19) of the cohort was overweight (57.9%; 11/19) or obese (26.3%; 5/19). The median BMI was 30.2 kg/m2 (range, 23.9–54.3 kg/m2). Conclusion. Preoperative percutaneous thoracic fiducial marker placement under imaging guidance is a safe method for facilitating intraoperative localization of the target spinal level, especially in obese patients. Further studies are needed to quantify changes in operative time and radiation exposure. Level of Evidence: 4

E-029 Mechanical Thrombectomy in Pediatric Acute Ischemic Stroke: Clinical Outcomes and Literature Review

There is limited data on outcomes of mechanical thrombectomy for pediatric stroke using modern devices. In this study, we report two cases of pediatric acute ischemic stroke treated with mechanical thrombectomy, both with good angiographic result (TICI 3) and clinical outcome (no neurological deficits at 90 days). In addition, we conducted a literature review of all previously reported cases describing the use of modern thrombectomy devices. Including our two cases, the aggregate rate of partial or complete vessel recanalization was 100% (22/22), and the aggregate rate of favorable clinical outcome was 91% (20/22). This preliminary evidence suggests that mechanical thrombectomy with modern devices may be a safe and effective treatment option in pediatric patients with acute ischemic stroke.Abstract E-029 Figure 1 Teenage boy status post gunshot wound to left face. (A) Gas in the carotid space (solid arrow) and non-opacification of the right internal carotid artery on neck CTA. (B) Pre-treatment angiogram demonstrates occlusion of the inferior division of the right MCA (dashed arrow). (C, D) Post-thrombectomy angiogram demonstrates TICI 3 flow. Disclosures T. Madaelil: None. A. Kansagra: None. C. Derdeyn: None. D. Cross: None. C. Moran: 2; C; Medtronic Neurovascular.