Olivary body exposure through far lateral and lower retrosigmoid approaches. Comparative analysis of the exposed surface and angle of attack.

Objectives: Throughout neurosurgical history, the treatment of intrinsic lesions located in the brainstem has been subject of much controversy. The brainstem is the anatomical structure of the central nervous system (CNS) that presents the highest concentration of nuclei and fibers, and its simple manipulation can lead to significant morbidity and mortality. Once one of the safe entry points at the medulla oblongata has been established, we wanted to evaluate the safest approach to the olivary body (the most used safe entry zone on the anterolateral surface of the medulla oblongata).

The temporary resection of the cranial vault by Wilhelm Wagner (1848-1900) instead of trepanation: the cornerstone of the modern craniotomy.

In this paper, the authors trace the history of cranial temporary resection, described by Wilhelm Wagner (1848-1900) in 1889, which changed the paradigm of the cranial opening from trephining to the craniotomy. The objective of the temporary resection was to obtain wide openings in the skull, keeping the cranial flap attached to the soft tissues to maintain bone vitality. The cranial temporary resection was reproduced by the authors in an anatomical study faithfully following the original technique, demonstrating the feasibility of the surgical procedure as described by Wagner.

The Smith-Robinson Approach to the Subaxial Cervical Spine: A Stepwise Microsurgical Technique Using Volumetric Models From Anatomic Dissections.

Background: The Smith-Robinson1 approach (SRA) is the most widely used route to access the anterior cervical spine. Although several authors have described this approach, there is a lack of the stepwise anatomic description of this operative technique. With the advent of new technologies in neuroanatomy education, such as volumetric models (VMs), the understanding of the spatial relation of the different neurovascular structures can be simplified.

Retrosigmoid Approach: A Simple and Safe Way to Resect Intrinsic Pontomedullary Lesions.

 The main objective of this article is to describe a simple and safe protocol for the microsurgical management of ventrally located intrinsic pontomedullary lesions based on the retrosigmoid approach, cortectomy performed utilizing safe entry zones of the pons and medulla, and a delicate microsurgical resection. The intraoperative protocol includes redundant procedures that provide security in decision-making during surgery.  A prospective series of 11 cases is presented.

Magnetic Resonance Imaging Surveillance for Vestibular Schwannoma After Microsurgical Resection Using a Retrosigmoid Transmeatal Approach.

Background: Vestibular schwannoma (VS) is a benign, usually slow-growing tumor. The drawback of radical microsurgical VS resection is the increased likelihood of neurologic injury, forcing surgeons to leave a tumor remnant in some cases. We evaluated the prognostic value of magnetic resonance imaging (MRI) enhancement patterns to determine the risk of tumor regrowth.

Side-to-End Hypoglossal-Facial Neurorrhaphy for Treatment of Complete and Irreversible Facial Paralysis after Vestibular Schwannoma Removal by Means of a Retrosigmoid Approach: A Clinical and Anatomic Study.

Background: Facial paralysis secondary to a complete and irreversible anatomic or functional lesion of the facial nerve (FN) causes severe functional and psychological disorders for the patient. A large number of surgical techniques have therefore been developed for FN repair. Our objective was to propose a surgical FN reanimation protocol for patients with irreversible anatomic or functional postsurgical injury of the FN in the cerebellopontine angle after vestibular schwannoma resection.

White Matter Relationships Examined by Transillumination Technique Using a Lateral Transcortical Parietal Approach to the Atrium: Three-Dimensional Images and Surgical Considerations.

Background: Numerous lesions are found in the ventricular atrium (VA). Access is gained through many white matter tracts with great relevance and specific neurologic functions. It is important to understand the configuration of the most relevant structures surrounding this zone and, thus, select the safest entry zone on the lateral cerebral surface.

Combined Extradural and Intradural Pterional Transzygomatic Approach to Large Sphenoid Wing Meningiomas. Operative Technique and Surgical Results.

 Describe a unique and safe surgical procedure for the microsurgical management of large sphenoid wing meningiomas (SWMs) aimed to a radical resection of these tumors.  A prospective series of 26 cases with SWMs larger than 3 cm in one of its main diameter is presented. All patients were studied following the same clinical and imaging procedures.

Microsurgical Anatomy of the Insular Region and Operculoinsular Association Fibers and its Neurosurgical Application.

Objective: To analyze the three-dimensional relationships of the operculoinsular compartments, using standard hemispheric and white matter fiber dissection and review the anatomy of association fibers related to the operculoinsular compartments of the Sylvian fissure and the main white matter tracts located deep into the insula. The secondary aim of this study was to improve the knowledge on this complex region to safely address tumor, vascular, and epilepsy lesions with an integrated perspective of the topographic and white matter fiber anatomy using 2D and 3D photographs.

Methods: Six cadaveric hemispheres were dissected.

Using NMR in saliva to identify possible biomarkers of glioblastoma and chronic periodontitis.

Nowadays there is increasing interest in identifying-and using-metabolites that can be employed as biomarkers for diagnosing, treating and monitoring diseases. Saliva and NMR have been widely used for this purpose as they are fast and inexpensive methods. This case-control study aimed to find biomarkers that could be related to glioblastoma (GBL) and periodontal disease (PD) and studied a possible association between GBL and periodontal status.

[Cranial trepanation in primitive cultures].

A review is presented on cranial trepanations performed by primitive cultures. The scientific interest in this topic began after the discovery in 1965 by Ephraim G. Squier of a pre-Columbian trepanated skull, and studied by Paul Broca in Paris.

[History of the craniotomy].

Craniotomy can be defined as the neurosurgical procedure aimed at achieving a wide cranial opening with the final purpose of performing a surgical therapeutic manoeuvre within the intracranial space. The current surgical technique for craniotomy is the final result of the development of the procedure since its introduction at the end of the 19th century. The very first wide cranial approach was introduced in 1889 by Wagner, and described as a 'temporary cranial resection'.

[Prognostic variability in atypical meningioma with complete resection. Proposed treatment algorithm].

Objective: The authors attempt to show how the current prognostic factors that try to assess the risk of recurrence of atypical meningiomas are insufficient to predict the future of this disease.

Materials And Method: Using data obtained from hospital databases, a sample of 27 patients was obtained with pathological diagnosis of atypical meningioma, and who had a minimum follow-up time of 6months after diagnosis. Later prognostic factors (age <50years, male gender, bone involvement, peri-lesional swelling, tumour volume, location, Ki67/MIB-1) were evaluated after the stratification of patients undergoing complete resection in recurrencies and non-recurrencies.

[Spinal cord stimulation and failed back surgery syndrome. Clinical results with laminectomy electrodes].

Introduction: Spinal cord stimulation is a widely-accepted technique in the treatment of back pain resulting from failed back surgery. Classically, stimulation has been carried out with percutaneous electrodes implanted under local anaesthesia and sedation. However, the ease of migration and the difficulty of reproducing electrical paresthesias in large areas with such electrodes has led to increasing use of surgical plate leads, which have the disadvantage of the need for general anaesthesia and a laminectomy for implantation.

Microsurgical Relations between Internal Carotid Artery-Posterior Communicating Artery (ICA-PComA) Segment Aneurysms and Skull Base: An Anatomoclinical Study.

Purpose The study of the clinical, anatomic, imaging, and microsurgical characteristics of the aneurysms of the internal carotid-posterior communicating artery (ICA-PComA) segment and their relationships with the skull base structures. Methods The anatomic relationships of PComA with neurovascular elements and skull base structures were studied in cadavers. The clinical, imaging, and microsurgical findings of 84 microsurgically treated ICA-PComA aneurysms compiled in a prospective database were reviewed.

[Transzygomatic pterional approach. Part 2: Surgical experience in the management of skull base pathology].

Objectives: To present our experience with the transzygomatic pterional approach in the treatment of neurosurgical pathology of the base of the skull located in the middle cranial fossa and surrounding areas.

Method: A retrospective study of pathological findings, surgical outcomes and complications in a series of 31 cases operated on between 2009 and 2011 using a transzygomatic pterional approach.

Results: The lesions involved the sphenoid wing (25.

[Transzygomatic pterional approach. Part 1: anatomical study].

Objective: Cadaveric study of the anatomical structures of the temporal region, as well as the technical aspects of the transzygomatic pterional approach.

Material And Methods: Six human formalin-fixed heads, whose arterial circulatory system was injected with red-dyed silicone, were studied (12 temporal regions). Dissections were performed using standard microsurgical techniques and instruments.

Magnetic resonance microscopy at 14 Tesla and correlative histopathology of human brain tumor tissue.

Magnetic Resonance Microscopy (MRM) can provide high microstructural detail in excised human lesions. Previous MRM images on some experimental models and a few human samples suggest the large potential of the technique. The aim of this study was the characterization of specific morphological features of human brain tumor samples by MRM and correlative histopathology.

Tumoral presentation of primary central nervous system lymphomatoid granulomatosis.

Purpose: Lymphomatoid granulomatosis (LYG) is an angiocentric Epstein-Barr virus (EBV) related B-cell proliferation associated with a reactive T-cell component with an uncertain malignant potential. LYG present at diagnosis as a mass lesion in the central nervous system (CNS) is rare, and only a few cases have been reported. In this article we present four cases of tumoral CNS-LYG and propose some guidelines for its management.

Metabolic aggressiveness in benign meningiomas with chromosomal instabilities.

Meningiomas are often considered benign tumors curable by surgery, but most recurrent meningiomas correspond to histologic benign tumors. Because alterations in chromosome 14 among others have suggested clinical aggressiveness and recurrence, determining both the molecular phenotype and the genetic profile may help distinguish tumors with aggressive metabolism. The aim of this study was to achieve higher specificity in the detection of meningioma subgroups by measuring chromosomal instabilities by fluorescence in situ hybridization and cytogenetics and metabolic phenotypes by high-resolution magic angle spinning spectroscopy.

Multimodal navigation in the functional microsurgical resection of intrinsic brain tumors located in eloquent motor areas: role of tractography.

Object: Nowadays the role of microsurgical management of intrinsic brain tumors is to maximize the volumetric resection of the tumoral tissue, minimizing the postoperative morbidity. The purpose of this paper was to study the benefits of an original protocol developed for the microsurgical treatment of tumors located in eloquent motor areas where the navigation and electrical stimulation of motor subcortical pathways have been implemented.

Methods: A total of 17 patients who underwent resection of cortical or subcortical tumors in motor areas have been included in the series.

Klippel-Feil syndrome associated with posterior fossa dermoid cyst. Case report.

A patient with association of Klippel-Feil syndrome and posterior fossa dermoid cyst is presented. The patient, a 36-year-old man, presented with an acute obstructive hydrocephalus due to the cyst and exhibited the typical triad of the Klippel-Feil abnormality with short neck, low hairline implantation and limited neck motion along with a complex cervical vertebrae fusion. The anatomical and clinical features as well as the pathophysiology of this rare association are discussed after a review of the literature.