No abstract

Insular gliomas with an MR imaging-defined tumor volume located lateral to the LSAs on stereotactic angiography displace the LSAs medially by expanding the insula, have well-demarcated tumor boundaries on MR images, and can be completely resected with minimal neurological morbidity. In contrast, insular tumors that appear to surround the LSAs do not displace these vessels medially, are poorly demarcated from normal brain parenchyma on MR images, and are associated with higher rates of neurological morbidity if aggressive resection is pursued. Preoperative identification of these anatomical growth patterns can be of value in planning resection.

Spinal dural arteriovenous fistulas (SDAVF) are a rare pathologic entity with a diverse and often misleading clinical presentation. While digital subtraction spinal angiography remains the gold standard, recent advances in noninvasive vascular imaging have improved the diagnosis of SDAVF. As this condition can result in permanent spinal cord injury, all patients require treatment, which consists of surgical or endovascular occlusion of the fistula. Failure to recognize and treat SDAVF in a timely fashion can result in irreversible neurologic disability, including myelopathy, lower extremity weakness and bowel, bladder and sexual dysfunction. This article reviews the clinical features, pathogenesis, radiographic features and current treatment strategies for these complex lesions.

The existing literature on preoperative spine tumor embolization is limited in size of patient cohorts and diversity of tumor histologies. This report presents our experience with preoperative embolization of hypervascular thoracic, lumbar, and sacral spinal column tumors in the largest series to date. We conducted a retrospective review of 228 angiograms and 188 pre-operative embolizations for tumors involving thoracic, lumbar and sacral spinal column. Tumor vascularity was evaluated with conventional spinal angiography and was graded from 0 (same as normal adjacent vertebral body) to 3 (severe tumor blush with arteriovenous shunting). Embolic materials included poly vinyl alcohol (PVA) particles and detachable platinum coils and rarely, liquid embolics. The degree of embolization was graded as complete, near-complete, or partial. Anesthesia records were reviewed to document blood loss during surgery. Renal cell carcinoma (44.2%), thyroid carcinoma (9.2%), and leiomyosarcoma (6.6%) were the most common tumors out of a total of 40 tumor histologies. Hemangiopericytoma had the highest mean vascularity (2.6) of all tumor types with at least five representative cases followed by renal cell carcinoma (2.0) and thyroid carcinoma (2.0). PVA particles were used in 100% of cases. Detachable platinum coils were used in 51.6% of cases. Complete, near-complete, and partial embolizations were achieved in 86.1%, 12.7%, and 1.2% of all cases, respectively. There were no new post-procedure neurologic deficits or other complications with long-term morbidity. The mean intra-operative blood loss for the hypervascular tumors treated with pre-operative embolization was 1745 cc. Preoperative embolization of hypervascular thoracic, lumbar, and sacral spine tumors can be performed with high success rates and a high degree of safety at high volume centers.

MMA embolization could present a minimally invasive and low-risk initial treatment alternative to surgery for symptomatic chronic SDH when clinically appropriate.

Advances in diagnostic imaging modalities and improved access to specialty care have led directly to an increased diagnosis of both metastatic and primary brain tumors. As technology has improved, so has the ability to treat this larger patient population. Diffusion tensor imaging (DTI) has recently shown the potential to aid in histologic diagnosis as well as to identify local brain invasion outside of that readily identifiable by conventional MRI. Similar to DTI, functional MRI provides a noninvasive means of delineating tumor margin from eloquent cortex and aids in preoperative surgical planning. As the literature shows increasing support for the advantages of extensive resection in glioma patients, modalities that aid in this regard are displaying increased importance. Surgeons have recently demonstrated the utility of intraoperative MRI in increasing extent of resection in both low- and high-grade glioma patients. Intraoperative tumor fluorescence provided by the chemical compound 5-aminolevulinic acid assists surgeons in identifying the true tumor margin during resection of glial neoplasms consequently increasing extent of resection. Finally, laser interstitial thermal therapy is an emerging treatment modality allowing surgeons to treat small intracranial lesions with potentially decreased morbidity via this minimally invasive approach. The following review analyzes the recent literature in an effort to describe how these modalities can and should be used in the treatment of patients with intracranial pathology.

Objective The existing literature regarding preoperative cervical spinal tumor embolization is sparse, with few discussions on the indications, risks, and best techniques. We present our experience with the preoperative endovascular management of hypervascular cervical spinal tumors. Methods We performed a retrospective review of all patients who underwent preoperative spinal angiography (regardless of whether tumor embolization was performed) at our institution (from 2002 to 2012) for primary and metastatic cervical spinal tumors. Tumor vascularity was graded from 0 (tumor blush equal to the normal adjacent vertebral body) to 3 (intense tumor blush with arteriovenous shunting). Tumors were considered “hypervascular” if they had a tumor vascular grade from 1 to 3. Embolic materials included particles, liquid embolics, and detachable coils. The main embolization technique was superselective catheterization of an arterial tumor feeder followed by injection of embolic material. This technique could be used alone or supplemented with occlusion of dangerous anastomoses of the vertebral artery as needed to prevent inadvertent embolization of the vertebrobasilar system. In cases when superselective catheterization of the tumoral feeder was not feasible, embolization was performed from a proximal catheter position after occlusion of branches supplying areas other than the tumor (“flow diversion”). Results A total of 47 patients with 49 cervical spinal tumors were included in this study. Of the 49 total tumors, 41 demonstrated increased vascularity (vascularity score > 0). The most common tumor pathology in our series was renal cell carcinoma (RCC) ( N = 16; 32.7% of all tumors) followed by thyroid carcinoma ( N = 7; 14.3% of all tumors). Tumor embolization was undertaken in 25 hypervascular tumors resulting in complete, near-complete, and partial embolization in 36.0% ( N = 9), 44.0% ( N = 11), and 20.0% ( N = 5) of embolized tumors, respectively. We embolized 42 tumor feeders in 25 tumors. The most commonly embolized tumor feeders were branches of the vertebral artery (19.0%; N = 8), the deep cervical artery (19.0%; N = 8), and the ascending cervical artery (19.0%; N = 8). Sixteen hypervascular tumors were not embolized because of minimal hypervascularity (8/16), unacceptably high risk of spinal cord or vertebrobasilar ischemia (4/16), failed superselective catheterization of tumor feeder (3/16), and cancellation of surgery (1/16). Vertebral artery occlusion was performed in 20% of embolizations. There were no new post-procedure neurological deficits or any serious adverse events. Estimated blood loss data from this cohort show a significant decrease in operative blood loss for embolized tumors of moderate and significant hypervascularity. Conclusions Preoperative embolization of cervical spinal tumors can be performed safely and effectively in centers with significant experience and a standardized approach.

No abstract