Microsurgical Resection for Cavernous Malformation of the Uncus: 3D-Operative Video.

Cavernous malformations (CMs) are rare and often oligosymptomatic vascular lesions. The main symptoms include seizure and focal neurologic deficits.1-3 Depending on the symptomatology, location, size, and risk factors for bleeding, like the presence of a developmental venous anomaly, CMs can be highly morbid. Thus surgical resection may be considered. Deep-seated and eloquent CMs, like those in the uncus, can be challenging.4,5 In Video 1, we present a 23-year-old male adult who developed focal seizures (i.e., oral automatisms) after an episode of sudden intense headache 1 year ago. His neurologic examination was unremarkable. The patient consented to the procedure and publication of his image. Nevertheless, his magnetic resonance images showed an uncal 2-cm Zabramski type I CM. We exposed the insula and its limen through a right pterional craniotomy and transsylvian corridor. During the video, we discuss the surgical nuances to access and resect this CM lesion en bloc while preserving important vascular structures and white matter tracts. Postoperative neuroimaging demonstrated total resection. In postoperative day 1, the patient had 1 episode of generalized seizure and evolved with contralateral hemiparesis. The patient had a good recovery and was discharged on postoperative day 21. At the 6-month follow-up, the patient had no new epileptic events and presented complete weakness improvement. Through this minimally invasive and well-known surgical corridor, we preserve the mesial and lateral portion of the temporal lobe, reducing the risk of lesions to the Meyer loop and limbic association area.

The Technique for Transorbital Ventricular Puncture: An Anatomic Approach.

BACKGROUND AND OBJECTIVES: Transorbital ventricular puncture is a minimally invasive described procedure with poor landmarks and anatomic references. This approach can be easily performed to save patients with intracranial hypertension, especially when it is secondary to an acute decompensated hydrocephalus. This study aims to describe anatomic structures and landmarks to facilitate the execution of transorbital puncture in emergency cases. METHODS: We analyzed 120 head computed tomographies to show the best area to perform the procedure in the orbital roof. Two adult cadavers (4 sides) were punctured in the predetermined area. Angles, distances, landmarks, and anatomic structures were registered. This approach to the ventricular system may be performed at bedside to relieve intracranial hypertension only in specific cases. RESULTS: The perforation point is 2.5 cm (female) or 3.0 cm (male) lateral to the midline and immediately inferior to the superciliary arch. A vertical line, parallel to midline, was drawn on the outer edge of the patient's forehead, the needle was 45° inferiorly and 20° medially and then progressed 2.0 cm backwards to reach the bone perforation point. After that, it was advanced another 4.5cm approximately until it reached the anterior horn of the lateral ventricle. CONCLUSION: Based on statistical and experimental evidences, we were able to establish reliable anatomic reference points to access the anterior horn of the lateral ventricle through transorbital puncture.

Posterior-Transcallosal Approach to a Choroidal Fissure Arteriovenous Malformation: Video of Adapting a "Bridging Vein Free" Corridor to This Complex Region.

Choroidal fissure arteriovenous malformations (ChFis-AVMs) are uncommon and challenging to treat due to their deep location and pattern of supply.1 The choroidal fissure lies between the thalamus and fornix, from the foramen of Monroe to the inferior choroidal point.2 AVMs in this location receive their supply from the anterior, lateral posterior choroidal artery and medial posterior choroidal arteries and drain to the deep venous system.3 The anterior-transcallosal corridor to the ChFis is favored due to the ease in opening the taenia fornicis from the foramen Monroe, and it increases in length for lesions located more posteriorly.4-7 We present a case of a posterior ChFis-AVM. The patient, a previously healthy woman in her 20s, presented with a sudden severe headache. She was diagnosed with intraventricular hemorrhage. This was managed conservatively with subsequent magnetic resonance imaging and digital subtraction angiography revealing a ChFis-AVM at the body of the left lateral ventricle, between the fornix and superior layer of the tela choroidae. It received its supply from the left lateral posterior choroidal artery and medial posterior choroidal artery and drained directly into the internal cerebral vein, classified as Spetzler-Martin grade II.8 A posterior-transcallosal approach to the ChFis was chosen to reduce the working distance and afford a wider corridor by avoiding cortical bridging veins (Video 1). Complete resection of the AVM was achieved with no additional morbidity. Microsurgery in experienced hands offers the best chance of cure for AVMs.9 In this case we demonstrate how to adapt the transcallosal corridor to the choroidal fissures for safe AVM surgery in this complex location.

The art of combining neuroanatomy and microsurgical skills in modern neurosurgery.

Neurosurgical training outside the operating room has become a priority for all neurosurgeons around the world. The exponential increase in the number of publications on training in neurosurgery reflects changes in the environment that future neurosurgeons are expected to work in. In modern practice, patients and medicolegal experts demand objective measures of competence and proficiency in the growing list of techniques available to treat complex neurosurgical conditions. It is important to ensure the myriad of training models available lead to tangible improvements in the operating room. While neuroanatomy textbooks and atlases are continually revised to teach the aspiring surgeon anatomy with a three-dimensional perspective, developing technical skills are integral to the pursuit of excellence in neurosurgery. Parapharsing William Osler, one of the fathers of neurosurgical training, without anatomical knowledge we are lost, but without the experience and skills from practice our journey is yet to begin. It is important to constantly aspire beyond competence to mastery, as we aim to deliver good outcomes for patients in an era of declining case volumes. In this article, we discuss, based on the literature, the most commonly used training models and how they are integrated into the treatment of some surgical brain conditions.