Sorenson, Thomas J.

Abstract MicroAVMs (microarteriovenous malformation) are arteriovenous shunts with a nidus smaller than 1 centimeter. 1 They are typically diagnosed after hemorrhage. When the nidus is very small, diagnosis can be challenging even on catheter angiography and careful examination of the arterial and capillary phases is required to identify the early shunt. Because of the very small size, identification and localization of the actual AV shunt can be problematic during surgical exploration. Advances in frameless stereotactic neuronavigation and the introduction of intraoperative indocyanine green (ICG) fluorescein provide useful adjuncts in the surgical treatment of these relatively uncommon lesions. In this video, we present 2 cases which document the value of intraoperative ICG fluorescein as well as some of the surgical pitfalls in the treatment of these lesions.

Abstract Intramedullary epidermoid cysts are extremely rare lesions. Preoperative diagnosis can be challenging due to non-specific imaging futures. We illustrate the case of a 32-year-old man who presented with a symptomatic intramedullary mass, which at surgery proved to be an epidermoid cyst. The spinal cord was decompressed by removing the pearl-white keratin material, although the capsule, which was tenaciously adherent to the surrounding spinal cord parenchyma, was only partially removed. In this video, we illustrate the salient surgical points for the resection of this very unusual intramedullary lesion.