Chapter 51 SURGICAL ANATOMY OF THE SKULL BASE AND CRANIAL NERVES

2021 ◽

Author(s):

Ralf A. Kockro ◽

Eike Schwandt ◽

Florian Ringel ◽

Christian Valentin Eisenring ◽

Wieslaw Lucjan Nowinski

Keyword(s):

Skull Base ◽

Clinical Setting ◽

Cranial Nerves ◽

Three Dimensional ◽

Surgical Anatomy ◽

University Hospital ◽

Complex Anatomy ◽

Operative Strategies ◽

Interactive 3D ◽

3D Exploration

Abstract Objective We evaluated the usefulness of a three-dimensional (3D) interactive atlas to illustrate and teach surgical skull base anatomy in a clinical setting. Study Design A highly detailed atlas of the adult human skull base was created from multiple high-resolution magnetic resonance imaging (MRI) and computed tomography (CT) scans of a healthy Caucasian male. It includes the parcellated and labeled bony skull base, intra- and extracranial vasculature, cranial nerves, cerebrum, cerebellum, and brainstem. We are reporting retrospectively on our experiences with employing the atlas for the simulation and teaching of neurosurgical approaches and concepts in a clinical setting. Setting The study was conducted at the University Hospital Mainz, Germany, and Hirslanden Hospital, Zürich, Switzerland. Participants Medical students and neurosurgical residents participated in this study. Results Handling the layered graphical user interface of the atlas requires some training; however, navigating the detailed 3D content from intraoperative perspectives led to quick comprehension of anatomical relationships that are otherwise difficult to perceive. Students and residents appreciated the collaborative learning effect when working with the atlas on large projected screens and markedly improved their anatomical knowledge after interacting with the software. Conclusion The skull base atlas provides an effective way to study essential surgical anatomy and to teach operative strategies in this complex region. Interactive 3D computer graphical environments are highly suitable for conveying complex anatomy and to train and review surgical concepts. They remain underutilized in clinical practice.

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Anatomical Step-by-Step Dissection of Complex Skull Base Approaches for Trainees: Surgical Anatomy of the Posterior Petrosal Approach

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0038-1675174 ◽

2018 ◽

Vol 80 (04) ◽

pp. 338-351 ◽

Cited By ~ 2

Author(s):

Christopher S. Graffeo ◽

Maria Peris-Celda ◽

Avital Perry ◽

Lucas P. Carlstrom ◽

Colin L.W. Driscoll ◽

...

Keyword(s):

Skull Base ◽

Cranial Nerves ◽

Skin Incision ◽

Surgical Anatomy ◽

Muscle Flaps ◽

Anatomical Dissection ◽

Superior Petrosal Sinus ◽

Key Steps ◽

Retrolabyrinthine Approach ◽

Burr Holes

Introduction Although numerous anatomical and operative atlases have been published, those that have focused on the skull base either have provided views that are quite difficult to achieve in the operating room to better depict surgical anatomy or are written at the level of an audience with considerable knowledge and experience. Methods Five sides of three formalin-fixed latex-injected specimens were dissected under microscopic magnification. A posterior petrosectomy approach was performed by three neurosurgical residents at different training levels with limited previous experience in anatomical dissection mentored by the senior authors (C. L. W. D. and M. J. L.) and a clinical skull base fellow with additional anatomical dissection experience (M. P. C.). Anatomical dissections were performed until the expected level of dissection quality was achieved to demonstrate each important step of the surgical approach that would be understandable to all trainees of all levels. Following dissection education, representative case applications were reviewed. Results The posterior petrosectomy (also known as presigmoid retrolabyrinthine approach) affords excellent access to cranial nerves III to XI and a diverse array of pathologies. Key steps include positioning and skin incision, scalp and muscle flaps, burr holes, craniotomy flap elevation, superficial mastoidectomy, otic capsule exposure and presigmoid dura decompression, primary presigmoid durotomy, inferior temporal durotomy, superior petrosal sinus ligation, tentorium sectioning, and final exposure. Conclusion The posterior petrosectomy is a challenging approach; thorough operative-style laboratory dissection is essential to provide trainees with a suitable guide. We describe a comprehensive approach to learning this technique, intended to be understandable and usable by a resident audience.

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The mandibular swing-transcervical approach to the skull base: anatomical study

Journal of Neurosurgery ◽

10.3171/jns.1993.78.4.0673 ◽

1993 ◽

Vol 78 (4) ◽

pp. 673-681 ◽

Cited By ~ 17

Author(s):

Mario Ammirati ◽

Jianya Ma ◽

Melvin L. Cheatham ◽

Zhong Tao Mei ◽

Joseph Bloch ◽

...

Keyword(s):

Carotid Artery ◽

Internal Carotid Artery ◽

Skull Base ◽

Internal Carotid ◽

Cranial Nerves ◽

Anatomical Study ◽

Surgical Anatomy ◽

Content Type ◽

Transcervical Approach ◽

Lower Cranial Nerves

✓ This report describes in a stepwise fashion the surgical anatomy of an approach to the midline and lateral compartments of the skull base (clivus, infralabyrinthine/infratemporal regions). The salient features of this procedure are represented by a mandibulotomy and by detachment of the pharynx from the skull base through a combined oral and cervical approach. There is full neurovascular control of the internal carotid artery and lower cranial nerves with the possibility of complete exposure of the intrapetrous and intracavernous segments of the internal carotid artery on the side of the exposure. This approach, which may be regarded as an expansion of the original work of Krespi, should be considered when dealing aggressively with extensive skull-base lesions invading the midline and lateral compartments of the skull base.

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Anatomical Step-by-Step Dissection of Complex Skull Base Approaches for Trainees: Surgical Anatomy of the Posterior Petrosal Approach

10.1055/s-0039-1679755 ◽

2019 ◽

Author(s):

Christopher Graffeo ◽

Maria Peris-Celda ◽

Avital Perry ◽

Lucas Carlstrom ◽

Colin Driscoll ◽

...

Keyword(s):

Skull Base ◽

Surgical Anatomy

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Full tractography for detecting the position of cranial nerves in preoperative planning for skull base surgery: technical note

Journal of Neurosurgery ◽

10.3171/2019.1.jns182638 ◽

2020 ◽

Vol 132 (5) ◽

pp. 1642-1652 ◽

Cited By ~ 2

Author(s):

Timothee Jacquesson ◽

Fang-Chang Yeh ◽

Sandip Panesar ◽

Jessica Barrios ◽

Arnaud Attyé ◽

...

Keyword(s):

Skull Base ◽

Preoperative Planning ◽

Skull Base Surgery ◽

Cranial Nerves ◽

Patient Specific ◽

Small Scale ◽

Skull Base Tumor ◽

Skull Base Tumors ◽

Brain White Matter ◽

Human Connectome Project

OBJECTIVEDiffusion imaging tractography has allowed the in vivo description of brain white matter. One of its applications is preoperative planning for brain tumor resection. Due to a limited spatial and angular resolution, it is difficult for fiber tracking to delineate fiber crossing areas and small-scale structures, in particular brainstem tracts and cranial nerves. New methods are being developed but these involve extensive multistep tractography pipelines including the patient-specific design of multiple regions of interest (ROIs). The authors propose a new practical full tractography method that could be implemented in routine presurgical planning for skull base surgery.METHODSA Philips MRI machine provided diffusion-weighted and anatomical sequences for 2 healthy volunteers and 2 skull base tumor patients. Tractography of the full brainstem, the cerebellum, and cranial nerves was performed using the software DSI Studio, generalized-q-sampling reconstruction, orientation distribution function (ODF) of fibers, and a quantitative anisotropy–based generalized deterministic algorithm. No ROI or extensive manual filtering of spurious fibers was used. Tractography rendering was displayed in a tridimensional space with directional color code. This approach was also tested on diffusion data from the Human Connectome Project (HCP) database.RESULTSThe brainstem, the cerebellum, and the cisternal segments of most cranial nerves were depicted in all participants. In cases of skull base tumors, the tridimensional rendering permitted the visualization of the whole anatomical environment and cranial nerve displacement, thus helping the surgical strategy.CONCLUSIONSAs opposed to classical ROI-based methods, this novel full tractography approach could enable routine enhanced surgical planning or brain imaging for skull base tumors.

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RARE-32. PEDIATRIC METASTATIC SKULL BASE CHORDOMA WITH TP53 MUTATION – A CASE REPORT AND REVIEW OF THE LITERATURE

Neuro-Oncology ◽

10.1093/neuonc/noaa222.742 ◽

2020 ◽

Vol 22 (Supplement_3) ◽

pp. iii449-iii449

Author(s):

Akira Shimada ◽

Kazuhiko Kurozumi ◽

Kiichiro Kanamitsu ◽

Hisashi Ishida Ishida ◽

Kaori Fujiwara ◽

...

Keyword(s):

Skull Base ◽

Tp53 Mutation ◽

Cranial Nerves ◽

Gamma Knife Radiosurgery ◽

Biological Behavior ◽

Maximum Diameter ◽

Cervical Lymph Nodes ◽

First Choice ◽

Systemic Metastasis ◽

Skull Base Chordoma

Abstract Chordoma is an uncommon bone tumor arising from notochordal remnant, which accounts for 1–4% of all bone malignancies. It commonly occurs along the cranial-spinal axis, and skull base is one of most frequent sites, representing 35–49% of all chordoma cases. Surgical resection is widely accepted as the first choice of treatment. There are only limited number of reports about pediatric chordoma cases, and its biological behavior including genetic backgrounds were largely unknown. Here, we present a 5 year-old girl with a large aggressive skull base chordoma of 6 cm in maximum diameter, which eventually had multiple systemic metastasis. We initially tried chemotherapy based on the protocol for the osteosarcoma, but in vain. Because the tumor was highly vascularized on angiography, after embolization of the feeding arteries and bilateral internal maxillary arteries, endoscopic endonasal surgery was performed. The tumor was sufficiently removed, achieving effective mass reduction, and the residual tumors involving the lower cranial nerves and craniocervial junction were additionally treated with Gamma Knife radiosurgery. However, one month later, it showed systemic metastasis to bilateral cervical lymph nodes and lung. We tried chemotherapy with nivolmab and imatinib for this patient, whereas they showed the partial effect. The genetic analysis revealed somatic TP53 c.569C>T, (p.P190L) mutation in chordoma specimen. In the past literature, we found only one study of the adult chordoma cases, in which majority of the patients had somatic TP53 mutation (p.P72R). Further investigation with large number of the cases is essential to clarify the molecular biology of pediatric chordomas.

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Image-Guided Multisession Radiosurgery of Skull Base Meningiomas

Cancers ◽

10.3390/cancers12123569 ◽

2020 ◽

Vol 12 (12) ◽

pp. 3569

Author(s):

Alfredo Conti ◽

Antonio Pontoriero ◽

Giuseppe Iatì ◽

Salvatore M. Cardali ◽

Anna Brogna ◽

...

Keyword(s):

Skull Base ◽

Stereotactic Radiosurgery ◽

Cranial Nerves ◽

Progression Free Survival ◽

Motor Deficits ◽

Intracranial Meningioma ◽

Treatment Schedule ◽

Fractionated Radiotherapy ◽

Patient Reported ◽

Skull Base Meningiomas

Background: The efficacy of single-session stereotactic radiosurgery (sSRS) for the treatment of intracranial meningioma is widely recognized. However, sSRS is not always feasible in cases of large tumors and those lying close to critically radiation-sensitive structures. When surgery is not recommended, multi-session stereotactic radiosurgery (mSRS) can be applied. Even so, the efficacy and best treatment schedule of mSRS are not yet established. The aim of this study is to validate the role of mSRS in the treatment of skull base meningiomas. Methods: A retrospective analysis of patients with skull base meningiomas treated with mSRS (two to five fractions) at the University of Messina, Italy, from 2008 to 2018, was conducted. Results: 156 patients met the inclusion criteria. The median follow-up period was 36.2 ± 29.3 months. Progression-free survival at 2-, 5-, and 10- years was 95%, 90%, and 80.8%, respectively. There were no new visual or motor deficits, nor cranial nerves impairments, excluding trigeminal neuralgia, which was reported by 5.7% of patients. One patient reported carotid occlusion and one developed brain edema. Conclusion: Multisession radiosurgery is an effective approach for skull base meningiomas. The long-term control is comparable to that obtained with conventionally-fractionated radiotherapy, while the toxicity rate is very limited.

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