Posterior Transtemporal Approach to a Thalamic Cavernous Malformation: 2-Dimensional Operative Video.

Cavernous malformations (CMs) account for 10%-15% of all vascular malformations and represent the second most common type of cerebral vascular lesion.1 They typically occur in the cerebral subcortex or white matter.2 CMs located in the thalamus are rare.3 When we isolate the group of thalamic CMs, we find a bleeding risk of >5% per year, with a rebleeding rate exceeding 60%, often occurring within 1 year of the initial bleeding.1 The deep location and proximity to eloquent brain regions make thalamic CMs challenging for neurosurgeons.4,5 Surgeons can access the posterolateral thalamus through various surgical approaches, such as transcallosal transventricular, supracerebellar transtentorial, intraparietal sulcus, and transcortical methods. Selecting the best surgical approach requires considerable expertise, considering the patient's preoperative condition and the lesion's location.6-12 We discuss a complex case involving a 24-year-old patient with a right thalamic cavernoma and a history of 3 prior bleeding events. We present a step-by-step transcortical approach through the posterior portion of the superior temporal gyrus (Video 1). The patient consented to the procedure and publication of images. We demonstrate how the transtemporal posterior trajectory provides an optimal working corridor for safely removing this cavernous malformation without introducing new deficits.

Topographical Systematization of Human Placenta Model for Training in Microneurosurgery.

BACKGROUND: Neurosurgical training continuously seeks innovative methods to enhance the acquisition of essential technical skills for neurosurgeons worldwide. While various training models have been employed, few truly replicate real-life conditions optimally. Human placenta is a good model for neurosurgical microsurgery training due to its anatomic similarities to neurovascular structures. Placental vessels exhibit a branching pattern and caliber comparable with intracranial vessels, making them suitable for practicing microsurgical techniques. The study aims to delineate the anatomic zones of the placenta and propose a segmented training model, resulting in a reproducible, cost-effective, and realistic neurosurgical microsurgery training environment. METHODS: Twenty human placentas were meticulously prepared, injected with dyes, and categorized into zones on the basis of anatomic features. Measurements of placental vessels were recorded and compared with cerebral vessels. The placenta was divided into 4 quadrants to facilitate specific training techniques. RESULTS: Our results revealed varying vessel diameters across placental zones, closely resembling cerebral vessels. Different microsurgical techniques were applied to specific placental zones, thereby optimizing training scenarios. The applicability section described exercises such as membrane dissection, vessel skeletonization, aneurysm creation, vascular bypass, and tumor dissection within the placental model, providing detailed guidance on the zones suitable for each exercise. CONCLUSIONS: Human placenta serves as an effective microsurgical training model for neurosurgery, enhancing neurosurgeons' skills through anatomic segmentation. Integrating this model into training programs can significantly contribute to skill acquisition and improved surgical outcomes. Further research is warranted to refine and expand its utilization, complemented by clinical experiences and other simulation tools.

Microsurgical Treatment for Arteriovenous Malformation in Eloquent Area: A 2-Dimensional Surgical Video and Step-by-Step Practical Guide.

Cerebral arteriovenous malformations (AVMs) are dynamic neurovascular disorders that occur mainly in young adults, presenting an annual risk of rupture of 2% - 4% per year.1 They can be asymptomatic, representing an incidental radiologic finding, or present with neurologic deficits according to their brain location, size, and presence or absence of bleeding.2,3 AVMs located in eloquent areas4 represent a great challenge for neurosurgeons, sometimes directed to alternatives therapies (e.g., embolization, radiotherapy) due to the difficulty in planning and surgical technique. Despite the complexity, we consider that there is benefit to removing these lesions; this can be done safely, as with the adequate microsurgical strategy and neuroanatomic knowledge. In Video 1, we show the case of a 55-year-old male patient with an AVM positioned over the right central sulcus. He presented with intermittent left-hand paresthesia followed by an episode of involuntary movements in the left arm without loss of consciousness and with spontaneous resolution. Angiography showed an AVM feed by branches of the middle cerebral artery and multiple venous drainage for the Trolard complex and superficial middle cerebral vein, with a 4-cm nidus, making it grade III in the Spetzler-Martin classification.4 The patient underwent surgery with total resection of the lesion without any complication or new neurologic deficits.