Exploring the Combination of Computer Vision and Surgical Neuroanatomy: A Workflow Involving Artificial Intelligence for the Identification of Skull Base Foramina.

Background: The skull base is a complex region in neurosurgery, featuring numerous foramina. Accurate identification of these foramina is imperative to avoid intraoperative complications and to facilitate educational progress in neurosurgical trainees. The intricate landscape of the skull base often challenges both clinicians and learners, necessitating innovative identification solutions.

Transpeduncular Approach for Resection of Ruptured Fourth Ventricular Arteriovenous Malformation.

The lateral recess of the fourth ventricle can be challenging to access surgically. We present a case of a previously ruptured arteriovenous malformation (AVM) of the fourth ventricle that was surgically resected via a retrosigmoid craniotomy and transinferior cerebellar peduncular approach. The patient is a 54-year-old female who experienced an intraventricular hemorrhage several months before presentation to our institution.

Superior Laryngeal Nerve Palsy After Anterior Cervical Diskectomy and Fusion: A Case Report and Cadaveric Description.

Background And Importance: Superior laryngeal nerve (SLN) injury after high cervical dissection can result in changes in vocal pitch due to cricothyroid denervation and dysphagia with aspiration risk because of decreased sensation of the supraglottic larynx.

Clinical Presentation: We describe a 69-year-old singer with cervical spondylotic myelopathy who underwent elective C3/4 and C4/5 anterior cervical diskectomy and fusion. Postoperatively, the patient reported changes in his voice, most noticeable with higher registers.

Assessment of Arterial Configurations of the Suprachiasmatic Region from the Endoscopic Endonasal Perspective: A Cadaveric Anatomical Study.

Background: Endoscopic endonasal surgery has proved to offer a practical route to treat suprasellar lesions, including tumors and vascular pathologies. Understanding the different configurations of the anterior cerebral communicating artery (ACoA) complex (ACoA-C) is crucial to properly navigate the suprachiasmatic space and decrease any vascular injury while approaching this region through an endonasal approach.

Methods: An endoscopic endonasal transplanum-transtubercular approach was performed on 36 cadaveric heads (72 sides).

Far-Lateral Transcondylar Approach to a Right Cervicomedullary Dural Arteriovenous Fistula of the Posterior Fossa.

 Dural arteriovenous fistulas (DAVFs) at the cervicomedullary junction are uncommon and often accompanied by subarachnoid hemorrhage (SAH). We aim to illustrate in detail the microsurgical procedure for treating a DAVF located at the cervicomedullary junction.  We present a two-dimensional operative video that includes clinical history, preoperative imaging, surgical strategy, still images with labels, clinical course, and postoperative imaging.

Endovascular embolization versus surgical clipping in a single surgeon series of basilar artery aneurysms: a complementary approach in the endovascular era.

Background: Currently, most basilar artery aneurysms (BAAs) are treated endovascularly. Surgery remains an appropriate therapy for a subset of all intracranial aneurysms. Whether open microsurgery would be required or utilized, and to what extent, for BAAs treated by a surgeon who performs both endovascular and open procedures has not been reported.

Retrosigmoid Craniectomy with a Layered Soft Tissue Dissection and Hydroxyapatite Reconstruction: Technical Note, Surgical Video, Regional Anatomy, and Outcomes.

 There are many reported modifications to the retrosigmoid approach including variations in skin incisions, soft tissue dissection, bone removal/replacement, and closure.  The aim of this study was to report the technical nuances developed by two senior skull base surgeons for retrosigmoid craniectomy with reconstruction and provide anatomic dissections, surgical video, and outcomes.  The regional soft tissue and bony anatomy as well as the steps for our retrosigmoid craniectomy were recorded with photographs, anatomic dissections, and video.

Microsurgical Techniques for Exposing the Internal Maxillary Artery in Cerebral Revascularization Surgery: A Comparative Cadaver Study.

Background: The internal maxillary artery (IMAX) is currently considered one of the main donor vessels in extracranial-to-intracranial bypass surgeries. Four main techniques for harvesting the IMAX have been described: via the anterior medial infratemporal fossa (AMITF), the middle infratemporal fossa (MITF), the anterior lateral middle fossa (ALMF), and the lateral middle fossa (LMF). The advantages and limitations of these techniques have not yet been systematically evaluated and compared.

Comparative Analysis of Pterional, Supraorbital, Extended Supraorbital, and Transtubercular-Transplanum Approaches for Exposing the Anterior Communicating Artery Complex: A Cadaveric Study.

Objective: We aimed to quantify and compare surgical exposure and freedom at the anterior communicating artery (ACoA) complex using pterional (PT), supraorbital (SO), extended supraorbital withorbital osteotomy (SOO), and endonasal endoscopic transtubercular-transplanum (EEATT) approaches.

Methods: Right-sided PT, SO, SOO, and EEATT approaches were performed using 10 cadaveric heads. Surgical exposure and freedom (horizontal and vertical attack angle) at the ACoA complex were measured.

Principles of Supplemental Motor Area and Cingulate Tumor Resection With Asleep Trimodal Motor Mapping: 2-Dimensional Operative Video.

Resection of intra-axial tumors adjacent to the motor pathways can lead to devastating deficits; however, with an appropriate mapping technique, it can be performed safely. We present the case of a 63-yr-old woman with a diffuse glioma centered in the left supplemental motor area (SMA) and extending throughout the cingulate gyrus. In the video, we demonstrate the principles developed by the senior author for trimodal motor mapping under general anesthesia.

Supracerebellar Approach for Resection of a Falcotentorial Dural Arteriovenous Fistula with Pial Tectal Arteriovenous Malformation Component Associated with a Left Parafalcine Meningioma.

A 66-year-old woman presented with a 4.5- × 4-cm left posterior parafalcine meningioma and visual loss in her left eye (Video 1). Prior to meningioma embolization, angiography confirmed an incidental high-risk falcotentorial dural arteriovenous fistula (DAVF) with pial tectal arteriovenous malformation (AVM) and flow-related aneurysms of the superior cerebellar artery (SCA) and posterior cerebral artery (PCA).

Replicating Skull Base Anatomy With 3D Technologies: A Comparative Study Using 3D-scanned and 3D-printed Models of the Temporal Bone.

Hypothesis: 3D technologies, including structured light scanning (SLS), microcomputed tomography (micro-CT), and 3D printing, are valuable tools for reconstructing temporal bone (TB) models with high anatomical fidelity and cost-efficiency.

Background: Operations involving TB require intimate knowledge of neuroanatomical structures-a demand that is currently met through dissection of limited cadaveric resources. We aimed to document the volumetric reconstruction of TB models using 3D technologies and quantitatively assess their anatomical fidelity.

Combined Pterional Transsylvian and Bifrontal Interhemispheric Approach to Ruptured Subcallosal and Pericallosal Brain Arteriovenous Malformation with Skeletonization of the Entire A2 ACA Segment.

A 39-year-old man presented with a large left paramedian frontal lobe intracerebral hemorrhage. Computed tomography angiography and magnetic resonance imaging revealed a tangle of vessels arising from the anterior cerebral arteries (ACAs) and dilated draining veins entering the superior sagittal sinus. Angiography confirmed a Spetzler-Martin grade 3, supplemented 2 arteriovenous malformation (AVM) with predominant supply from branches of the left ACA with superficial and deep drainage (Video 1).

An Anatomic Feasibility Study for Revascularization of the Ophthalmic Artery, Part I: Intracanalicular Segment.

Background: The anatomico-functional complexity of the ophthalmic segment aneurysms is attributable to the presence of critical neurovascular structures in the surgical field. Surgical clipping of the ophthalmic artery (OpA) aneurysms can result in postoperative visual deficit due to the complexity of the aneurysm, vasospasm, or optic nerve manipulation. In this study, we aimed to characterize the feasibility of an intracanalicular OpA (iOpA) revascularization with 2 donor vessels: an intracranial-intracranial (IC-IC) bypass using the anterior temporal artery (ATA) and an extracranial-intracranial (EC-IC) bypass using the superficial temporal artery (STA).

An Anatomical Feasibility Study for Revascularization of the Ophthalmic Artery. Part II: Intraorbital Segment.

Introduction: Distal ophthalmic artery (OpA) aneurysms are a rare subset of vascular lesions with lack of optimal treatment. The management of these aneurysms may require complete occlusion of the parent vessel, carrying a risk of permanent visual impairment due to individual variations of extracranial collateral flow to the intraorbital ophthalmic artery (iOpA).

Objective: To test the feasibility of a superficial temporal artery (STA) to iOpA bypass to prevent acute ischemic retinal injury.

Supracerebellar Approach to Radiation-Induced Giant Capillary Telangiectasia Within Juvenile Pilocytic Astrocytoma of Upper Brainstem.

Radiation-induced telangiectasia of the central nervous system has been described predominantly in children, with up to 20% of patients affected after 3-41 years of radiotherapy. We present the case of a 45-year-old male with a pontine pilocytic astrocytoma treated with standard-dose radiation for 6 weeks in 1993. He developed a 3-cm multicystic, hemorrhagic brainstem lesion but was asymptomatic.

Characterization of Anatomical Landmarks for Exposing the Internal Carotid Artery in the Infratemporal Fossa Through an Endoscopic Transmasticator Approach: A Morphometric Cadaveric Study.

Background: The Eustachian tube and sphenoid spine have been previously described as landmarks for endonasal surgical identification of the most distal segment of the parapharyngeal internal carotid artery (PhICA). However, the intervening space between the sphenoid spine and PhICA allows for error during exposure of the artery. In the present study, we have characterized endoscopic endonasal transmasticator exposure of the PhICA using the sphenoid spine, vaginal process of the tympanic bone, and the "tympanic crest" as useful anatomical landmarks.

Stereoscopy in Surgical Neuroanatomy: Past, Present, and Future.

Since the dawn of antiquity, scientists, philosophers, and artists have pondered the nature of optical stereopsis-the perception of depth that arises from binocular vision. The early 19th century saw the advent of stereoscopes, devices that could replicate stereopsis by producing a 3D illusion from the super-imposition of 2D photographs. This phenomenon opened up a plethora of possibilities through its usefulness as an educational tool-particularly in medicine.

Acquisition of Volumetric Models of Skull Base Anatomy Using Endoscopic Endonasal Approaches: 3D Scanning of Deep Corridors Via Photogrammetry.

Objective: In this study we aim to evaluate the feasibility of creating volumetric models of highly intricate skull-base anatomy-previously not amenable to volumetric reconstruction-using endoscopic endonasal approaches.

Methods: Ten human cadaveric heads were dissected through the nasal corridor to expose anterior, middle, and posterior cranial fossi structures and the pterygopalatine and infratemporal fossi. A rigid endoscope with a 30° lens was used to capture the images.

Comparative Analysis of the Subtonsillar, Far-Lateral, Extreme-Lateral, and Endoscopic Far-Medial Approaches to the Lower Clivus: An Anatomical Cadaver Study.

Background: The lower clivus (LC) is one of the most difficult areas to access in neurosurgery. Several microsurgical approaches to the LC have been reported, including the subtonsillar, far-lateral (FL), extreme-lateral (EL), and endoscopic far-medial (Endo-FM). However, no consensus has been reached regarding the optimal approach.

Revascularization of the Anterior Inferior Cerebellar Artery Using Extracranial and Intracranial Donors: A Morphometric Cadaveric Study.

Introduction: Anterior inferior cerebellar artery (AICA) aneurysms are rare, accounting for 0.2%-1.3% of all intracranial aneurysms.

Clipping of High-Risk Dural Arteriovenous Fistula of the Posterior Fossa: 3-Dimensional Operative Video.

Dural arteriovenous fistulas (DAVFs) represent 10%-15% of all intracranial arteriovenous malformations. DAVFs located in the posterior cranial fossa are rare and often present with intracranial hemorrhage and myelopathy. Arterial supply could be provided by the meningeal branches of the vertebral artery and external and internal carotid arteries.

Construction of Neuroanatomical Volumetric Models Using 3-Dimensional Scanning Techniques: Technical Note and Applications.

Background: Visuospatial features of neuroanatomy are likely the most difficult concepts to learn in anatomy. Three-dimensional (3D) modalities have gradually begun to supplement traditional 2-dimensionanl representations of dissections and illustrations. We have introduced and described the workflow of 2 innovative methods-photogrammetry (PGM) and structured light scanning (SLS)-which have typically been used for reverse-engineering applications.

Local in situ fibrinolysis for recanalization of an occluded extracranial-intracranial bypass: Technical note.

Extracranial-intracranial (EC-IC) bypass is a versatile technique to augment or preserve blood flow when treating cerebrovascular pathologies to prevent ischemic complications. Technical success and good patient outcomes rely on the successful establishment and maintenance of a patent bypass graft. Multiple modalities have been developed to confirm intraoperative graft patency.