Transanterior Limiting Sulcus of the Insula Approach: Novel Surgical Approach to the Ventral Striatum Region.

Background: Lesions in the ventral striatum region (above the anterior perforated substance) are a challenge for neurosurgeons due to their direct relationship with the lenticulostriate arteries, which difficult the surgical access. The standard approaches for this region include the following: 1) transfrontal approach, 2) transanterior perforating substance approach, 3) transcallosal transventricular approach, and 4) pterional transsylvian-transinsular route. In this study, we aimed to describe a novel anatomical approach through the anterior limiting sulcus of the insula in order to access the ventral striatum.

Diffuse large B-cell lymphoma of the central nervous system presenting as "lymphomatosis cerebri" and dementia in elderly man: Case report and review of the literature.

Rationale: Lymphomatosis cerebri is a rare form of PCNSL, characterized by diffuse infiltration of lymphoma cells in cerebral parenchyma, without mass-formation and mild or no contrast enhancement on magnetic resonance (MR) imaging. There are less than 50 cases described in the literature under the term Lymphomatosis cerebri.

Patient Concerns: A 74-year-old man presented to our service with progressive dementia for 12 months and accelerated cognitive decline within the last two months.

Microsurgical anatomy of the central core of the brain.

OBJECTIVE The purpose of this study was to describe in detail the cortical and subcortical anatomy of the central core of the brain, defining its limits, with particular attention to the topography and relationships of the thalamus, basal ganglia, and related white matter pathways and vessels. METHODS The authors studied 19 cerebral hemispheres. The vascular systems of all of the specimens were injected with colored silicone, and the specimens were then frozen for at least 1 month to facilitate identification of individual fiber tracts.

Microsurgical anatomy and internal architecture of the brainstem in 3D images: surgical considerations.

OBJECT Brainstem surgery remains a challenge for the neurosurgeon despite recent improvements in neuroimaging, microsurgical techniques, and electrophysiological monitoring. A detailed knowledge of the microsurgical anatomy of the brainstem surface and its internal architecture is mandatory to plan appropriate approaches to the brainstem, to choose the safest point of entry, and to avoid potential surgical complications. METHODS An extensive review of the literature was performed regarding the brainstem surgical approaches, and their correlations with the pertinent anatomy were studied and illustrated through dissection of human brainstems properly fixed with 10% formalin.

Three-dimensional digital projection in neurosurgical education: technical note.

Three-dimensional images have become an important tool in teaching surgical anatomy, and its didactic power is enhanced when combined with 3D surgical images and videos. This paper describes the method used by the last author (G.C.

Head positioning for anterior circulation aneurysms microsurgery.

Objective: To study the ideal patient's head positioning for the anterior circulation aneurysms microsurgery.

Method: We divided the study in two parts. Firstly, 10 fresh cadaveric heads were positioned and dissected in order to ideally expose the anterior circulation aneurysm sites.

Alternative cost-effective method to record 3D intra-operative images: a technical note.

The educational value of stereoscopic imaging in neurosurgical training has increasingly been appreciated and its use increased during the last decade. We describe a technique that we developed to acquire and reproduce intra-operative stereoscopic images.

Isolation, cultivation and characterization of CD133+ stem cells from human glioblastoma.

Objective: To establish the method of isolation and culture of human glioblastoma neurospheres, and the purification of their stem cells, followed by the process of obtaining tumor subspheres, immunophenotypically characterizing this clonogenic set.

Methods: Through the processing of glioblastoma samples (n=3), the following strategy of action was adopted: (i) establish primary culture of glioblastoma; (ii) isolation and culture of tumor neurospheres; (iii) purify cells that initiate tumors (CD133+) by magnetic separation system (MACS); (iv) obtain tumor subspheres; (v) study the expression of the markers nestin, CD133, and GFAP.

Results: The study successfully described the process of isolation and culture of glioblastoma subspheres, which consist of a number of clonogenic cells immunophenotypically characterized as neural, which are able to initiate tumor formation.

The pterional craniotomy: tips and tricks.

This review intended to describe in a didactic and practical manner the frontotemporosphenoidal craniotomy, which is usually known as pterional craniotomy and constitute the cranial approach mostly utilized in the modern neurosurgery. This is, then, basically a descriptive text, divided according to the main stages involved in this procedure, and describes with details how the authors currently perform this craniotomy.

Microsurgical anatomy of the optic radiation and related fibers in 3-dimensional images.

Background: The fiber dissection technique provides unique 3-dimensional anatomic knowledge of the white matter.

Objective: To examine the optic radiation anatomy and its important relationship with the temporal stem and to discuss its findings in relation to the approaches to temporal lobe lesions.

Methods: We studied 40 cerebral hemispheres of 20 brains that had been fixed in formalin solution for 40 days.

Supracerebellar transtentorial approach-resection of the tentorium instead of an opening-to provide broad exposure of the mediobasal temporal lobe: anatomical aspects and surgical applications: clinical article.

Object: The aim of this study was to describe the surgical anatomy of the mediobasal aspect of the temporal lobe and the supracerebellar transtentorial (SCTT) approach performed not with an opening, but with the resection of the tentorium, as an alternative route for the neurosurgical management of vascular and tumoral lesions arising from this region.

Methods: Cadaveric specimens were used to illustrate the surgical anatomy of the mediobasal region of the temporal lobe. Demographic aspects, characteristics of lesions, clinical presentation, surgical results, follow-up findings, and outcomes were retrospectively reviewed for patients referred to receive the SCTT approach with tentorial resection.

Microsurgical anatomy of the posterior cerebral artery in three-dimensional images.

Objective: To describe the microsurgical anatomy, branches, and anatomic relationships of the posterior cerebral artery (PCA) represented in three-dimensional images.

Methods: Seventy hemispheres of 35 brain specimens were studied. They were previously injected with red silicone and fixed in 10% formalin for at least 40 days.

The cerebral sulci and gyri.

The aim of this study was to describe in detail the microanatomy of the cerebral sulci and gyri, clarifying the nomenclature for microneurosurgical purposes. An extensive review of the literature regarding the historical, evolutionary, embryological, and anatomical aspects pertinent to human cerebral sulci and gyri was conducted, with a special focus on microneuroanatomy issues in the field of neurosurgery. An intimate knowledge of the cerebral sulci and gyri is needed to understand neuroimaging studies, as well as to plan and execute current microneurosurgical procedures.

[Neuroanatomical basis of behavior: history and recent contributions].

Considering the most recent contributions, the limbic cortical areas, originally known as the greater limbic lobe, besides the cingulated and the parahippocampal gyri also includes the insula and the posterior orbital cortex. In contrast to the nonlimbic cortical areas that project to the basal ganglia (particularly over the dorsal aspects of the striatum, constituted by the caudate nucleus and by the putamen), the limbic cortical areas are characterized by projecting to the hypothalamus and also to the ventral striatum (particularly to the nucleus accumbens). Once all the striatum projects to the globus pallidus which projects to the thalamus and then to the cortex, generating cortical-subcortical reentrant circuits, while the dorsal striatum and pallidum related cortico-subcortical loops are involved with motor activities, the ventral cortical-striatal-pallidal system is particularly related with behavior functions.

[The pterional craniotomy: step by step].

This article intends to describe in a didactical and practical manner the frontotemporosphenoidal craniotomy, that is usually known as pterional craniotomy and that constitute the cranial approach mostly utilized in the modern neurosurgery. This is then basically a descriptive text, divided according to the main stages involved in this procedure, and that describes with details how the authors currently perform this craniotomy.

[The insula and the central core concept].

The characterization of well defined and circumscribed brain regions is particularly useful for the neurosurgical practice once it enhances the tridimensional understanding of its structures and related lesions, and because it induces the development and the utilization of more standard microneurosurgical approaches. In this direction, it is noteworthy that each cerebral hemisphere harbors an evident central core constituted externally by the insula, internally by the basal ganglia and the thalamus, and with the internal capsule within. With a biconvex configuration when seen from above, and located between the sylvian cistern and the supratentorial ventricular cavities, morphologically this central core resembles a head of each brainstem half top, covered by the neocortical mantle of its hemisphere.

The suprapetrosal craniotomy.

Objective: The primary aim of this study was to establish standard sites for bur holes that maintain constant anatomical relationships with the skull base and neural structures and can serve as the basal aspect of supratentorial temporooccipital craniotomies.

Methods: To determine cranial-cerebral relationships, the authors created bur holes in 16 adult cadaveric skulls. Three bur holes were made on each side of the skulls (32 cerebral hemispheres).

[Considerations about the nervous system phylogenetic evolution, behavior, and the emergence of consciousness].

This text reviews the generic aspects of the central nervous system evolutionary development, emphasizing the developmental features of the brain structures related with behavior and with the cognitive functions that finally characterized the human being. Over the limbic structures that with the advent of mammals were developed on the top of the primitive nervous system of their ancestrals, the ultimate cortical development with neurons arranged in layers constituted the structural base for an enhanced sensory discrimination, for more complex motor activities, and for the development of cognitive and intellectual functions that finally characterized the human being. The knowledge of the central nervous system phylogeny allow us particularly to infer possible correlations between the brain structures that were developed along phylogeny and the behavior of their related beings.

Surgical management of intracranial complications of otogenic infection.

We conducted a prospective study of 24 patients to evaluate the evolution of intracranial complications resulting from otogenic infection and to correlate the course of the disease with surgical treatment. Almost half of the patients were younger than 18 years, and most were male. The most common intracranial complication was brain abscess, followed by meningitis, lateral sinus thrombosis, and extradural abscess.

Transient evoked otoacoustic emissions after vestibular nerve section in chinchillas.

Transient evoked otoacoustic emissions are believed to be sensitive to the effects of the cochlear efferent system. The most well-known function of this system is inhibitory on cochlear response. It has been demonstrated that crossed medial efferent system section produces inhibitory control of the outer hair cells mechanisms responsible for non-linear transient evoked otoacoustic emissions generation.