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1.
Oper Neurosurg (Hagerstown) ; 24(3): e178-e186, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36701601

RESUMO

BACKGROUND: Surgery for lesions located in the medial frontal and parietal lobes can be quite challenging for neurosurgeons because of morbidities that may arise from damage to critical midline structures or intact neural tissue that need to be crossed to reach the lesion. In our anatomic studies, the cingulate sulcus was observed as an alternative access route for lesions located in medial frontal and parietal lobes. OBJECTIVE: To explain the microsurgical anatomy of the medial hemisphere and cingulate sulcus and to demonstrate the interhemispheric transcingulate sulcus approach (ITCSA) with 3 clinical cases. METHODS: Five formalin-fixed brain specimens, which were frozen at -18 °C for at least 2 weeks and then thawed under tap water, were gradually dissected from medial to lateral. Diffusion fiber tracking performed using DSI Studio software in data was provided by the Human Connectome Project. Clinical data of 3 patients who underwent ITCSA were reviewed. RESULTS: Cingulate sulcus is an effortlessly identifiable continuous sulcus on the medial surface of the brain. Our anatomic dissection study revealed that the lesions located in the deep medial frontal and parietal lobes can be reached through the cingulate sulcus with minor injury only to the cingulum and callosal fibers. Three patients were treated with ITCSA without any neurological morbidity. CONCLUSION: Deep-seated lesions in the medial frontal lobe and parietal lobe medial to the corona radiata can be approached by using microsurgical techniques based on anatomic information. ITCSA offers an alternative route to these lesions besides the known lateral transcortical/transsulcal and interhemispheric transcingulate gyrus approaches.


Assuntos
Córtex Cerebral , Substância Branca , Humanos , Lobo Parietal/cirurgia , Lobo Parietal/anatomia & histologia , Lobo Frontal/cirurgia , Lobo Frontal/anatomia & histologia , Encéfalo , Substância Branca/anatomia & histologia
2.
Sci Rep ; 12(1): 21402, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36496517

RESUMO

Despite being associated with high-order neurocognitive functions, the frontal lobe plays an important role in core neurological functions, such as motor and language functions. The aim of this study was to present a neurosurgical perspective of the cortical and subcortical anatomy of the frontal lobe in terms of surgical treatment of intraaxial frontal lobe lesions. We also discuss the results of direct brain mapping when awake craniotomy is performed. Ten adult cerebral hemispheres were prepared for white matter dissection according to the Klingler technique. Intraaxial frontal lobe lesions are approached with a superior or lateral trajectory during awake conditions. The highly eloquent cortex within the frontal lobe is identified within the inferior frontal gyrus (IFG) and precentral gyrus. The trajectory of the approach is mainly related to the position of the lesion in relation to the arcuate fascicle/superior longitudinal fascicle complex and ventricular system. Knowledge of the cortical and subcortical anatomy and its function within the frontal lobe is essential for preoperative planning and predicting the risk of immediate and long-term postoperative deficits. This allows surgeons to properly set the extent of the resection and type of approach during preoperative planning.


Assuntos
Neoplasias Encefálicas , Córtex Motor , Substância Branca , Adulto , Humanos , Substância Branca/diagnóstico por imagem , Substância Branca/cirurgia , Substância Branca/anatomia & histologia , Neoplasias Encefálicas/patologia , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/cirurgia , Lobo Frontal/anatomia & histologia , Mapeamento Encefálico/métodos , Idioma
3.
World Neurosurg ; 148: e674-e679, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33508488

RESUMO

OBJECTIVE: We analyzed cortical landmarks, trajectory of approach, and various fiber tracts in the vicinity of our earlier described approach through the orbital/basal surface of the frontal lobe to access tumors located in the region of the caudate nucleus. We also present a new lateral orbital trajectory to approach these tumors. METHODS: The orbital surfaces of 3 formalin fixed and frozen cadaveric brain specimens were dissected to decipher the white fibers in the region of the caudate nucleus. Safe trajectories to lesions of the head of the caudate nucleus were identified, and the anatomic landmarks of the approach were evaluated. Three patients with caudate head tumors were operated using this approach. RESULTS: The caudate head lies at an average distance of 34 mm from the tip of the frontal pole, 24 mm from the basal medial orbital surface of the frontal lobe, 35 mm from the basal lateral orbital surface, and 37 mm from the superior surface of the frontal lobe. Two avenues were identified to approach the caudate head: one by making a cortical incision in the lateral orbital gyrus (lateral orbital approach), and the second by making a corticectomy in the medial orbital gyrus (medial orbital approach) in line with the temporal pole. All 3 patients were operated successfully using this approach. CONCLUSIONS: Surgical approach to the caudate head through the orbital surface of the frontal lobe as described by us provides the shortest trajectory and safe surgical route to access tumors of the caudate nucleus.


Assuntos
Neoplasias Encefálicas/cirurgia , Núcleo Caudado/anatomia & histologia , Núcleo Caudado/cirurgia , Procedimentos Neurocirúrgicos/métodos , Córtex Pré-Frontal/anatomia & histologia , Córtex Pré-Frontal/cirurgia , Adulto , Pontos de Referência Anatômicos , Cadáver , Feminino , Lobo Frontal/anatomia & histologia , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Fibras Nervosas , Rede Nervosa/anatomia & histologia , Rede Nervosa/cirurgia , Adulto Jovem
4.
Neuroimage Clin ; 25: 102192, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32014826

RESUMO

The presence of the superior fronto-occipital fascicle (SFOF) has been reported in the Rhesus monkey; however, it is a subject of controversy in humans. The aim of this study is to identify the SFOF using both in vitro and in vivo anatomo-functional analyses. This study consisted of two approaches. First, one acallosal brain and 12 normal postmortem hemispheres (five left and seven right sides) were dissected under a microscope using Klingler's fiber dissection technique. We focused on the medial subcallosal area superior to the Muratoff bundle, which has been indicated as a principal target area of the SFOF in previous studies. Second, 90 patients underwent awake craniotomy for gliomas with direct electrical stimulations. Functional examinations for visual, ataxic, and cognitive tasks were performed and 453 positive mapping sites were investigated by voxel-based morphometry analysis to establish the functions of the SFOF. The corticostriatal fibers, or the Muratoff bundle, and thalamic peduncle fibers joined in the area of the caudate nucleus, making thalamic peduncle/ corticostriatal bundles, which ran antero-posteriorly in the anterior subcallosal area and radiated from the caudate superior margin in the posterior subcallosal area. However, no SFOF fiber bundle crossed perpendicular to the thalamic peduncle/ corticostriatal bundles in the posterior subcallosal area. In the acallosal hemispheres, Probst bundles were confirmed and the subcallosal areas did not show a specific organization different from the normal brain. Hence, we could not detect a long and continuous association fascicle connecting the frontal lobe and occipital or parietal lobe in the target areas. Furthermore, in the in vivo functional mappings of awake surgery and voxel-based morphometry analysis, eight positive points on the SFOF were selected from the total 453 positive points, but their functions were not related with visual processing and spatial awareness, as has been reported in previous studies. In conclusion, in the present study we attempted to investigate the existence of the SFOF using an anatomical and functional approach. According to our results, the SFOF may not exist in the human brain.


Assuntos
Mapeamento Encefálico , Neoplasias Encefálicas/cirurgia , Craniotomia , Imagem de Tensor de Difusão , Glioma/cirurgia , Vias Neurais/anatomia & histologia , Vias Neurais/fisiologia , Substância Branca/anatomia & histologia , Substância Branca/fisiologia , Adolescente , Adulto , Idoso , Autopsia , Mapeamento Encefálico/métodos , Imagem de Tensor de Difusão/métodos , Feminino , Lobo Frontal/anatomia & histologia , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Vias Neurais/patologia , Lobo Occipital/anatomia & histologia , Lobo Occipital/diagnóstico por imagem , Lobo Occipital/fisiologia , Vigília/fisiologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Adulto Jovem
5.
World Neurosurg ; 132: e909-e921, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31351206

RESUMO

BACKGROUND: Magnetic resonance imaging-guided laser interstitial thermal therapy (LITT) is an emerging minimally invasive procedure for the treatment of deep intracranial lesions. Insular lesions are challenging to treat because of the risk of damaging important surrounding structures. The precise knowledge of the neural structures that are at risk along the trajectory and during the ablation is essential to reduce associated complications. This study aims to describe the relevant anatomy of the anterior frontal LITT trajectory to the insular region by using sectional anatomy and fiber dissection technique. METHODS: Three silicone-injected cadaveric heads were used to implant laser catheters bilaterally to the insular region by using a frameless stereotactic technique from a frontal approach. Sections were cut in both the oblique axial plane parallel to the trajectory and in the coronal plane. White matter fiber dissections were used to establish the tracts related to the laser trajectory from lateral to medial and medial to lateral. RESULTS: Supraorbital regions were selected as entry points. After crossing the frontal bone, the track intersected the inferior frontal lobe. The catheter was illustrated reaching the insular region medial to the inferior fronto-occipital fasciculus and insular cortex, and superior to the uncinate fasciculus. The uncinate fasciculus, extreme capsule, claustrum, external capsule, and putamen were traversed, preserving the major vascular structures. CONCLUSIONS: Independent of the insular area treated, an understanding of the neuroanatomy related to the anterior frontal laser trajectory is essential to improve the ability to perform LITT of this challenging region.


Assuntos
Córtex Cerebral/anatomia & histologia , Claustrum/anatomia & histologia , Cápsula Externa/anatomia & histologia , Lobo Frontal/anatomia & histologia , Putamen/anatomia & histologia , Substância Branca/anatomia & histologia , Cadáver , Córtex Cerebral/cirurgia , Humanos , Terapia a Laser , Imageamento por Ressonância Magnética , Microcirurgia , Técnicas Estereotáxicas , Cirurgia Assistida por Computador
6.
Surg Radiol Anat ; 41(8): 889-900, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31028450

RESUMO

PURPOSE: The arcuate fasciculus (AF) is a white matter fibers tract that links the lateral temporal with the frontal cortex. The AF can be divided into three components: two superficial indirect short tracts (anterior and posterior) and one deep direct long tract. Both DTI and white matter dissections studies find differences regarding the anatomy of the AF, especially its cortical connections. This paper aims at providing a comprehensive anatomical classification of the AF, using the terminologia anatomica. METHODS: Articles (n = 478) were obtained from a systematical PRISMA review. Studies which focused on primates, unhealthy subjects, as well as studies without cortical termination description and review articles were excluded from the analysis. One hundred and ten articles were retained for full-text examination, of which 19 finally fulfilled our criteria to be included in this review. RESULTS: We classified main descriptions and variations of each segment of the AF according to fiber orientation and cortical connections. Three types of connections were depicted for each segment of the AF. Concerning the anterior segment, most of the frontal fibers (59.35%) ran from the ventral portion of the precentral gyrus and the posterior part of the pars opercularis, to the supramarginal gyrus (85.0%). Main fibers of the posterior segment of the AF ran from the posterior portion of the middle temporal gyrus (100%) to the angular gyrus (92.0%). In main descriptions of the long segment of the AF, fibers ran from both the ventral portion of the precentral gyrus and posterior part of the pars opercularis (63.9%) to the middle and inferior temporal gyrus (60.3%). Minor subtypes were described in detail in the article. CONCLUSION: We provide a comprehensive classification of the anatomy of the AF, regarding the orientation and cortical connections of its fibers. Although fiber orientation is very consistent, cortical endings of the AF may be different from one study to another, or from one individual to another which is a key element to understand the anatomical basis of current models of language or to guide intraoperative stimulation during awake surgery.


Assuntos
Variação Anatômica , Lobo Frontal/anatomia & histologia , Vias Neurais/anatomia & histologia , Lobo Temporal/anatomia & histologia , Substância Branca/anatomia & histologia , Imagem de Tensor de Difusão , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/fisiologia , Humanos , Monitorização Neurofisiológica Intraoperatória/métodos , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologia , Procedimentos Neurocirúrgicos/métodos , Fala/fisiologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiologia , Vigília , Substância Branca/diagnóstico por imagem , Substância Branca/fisiologia
7.
Oper Neurosurg (Hagerstown) ; 17(2): 182-192, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30418653

RESUMO

BACKGROUND: The ventral part of the precentral gyrus is considered one of the most eloquent areas. However, little is known about the white matter organization underlying this functional hub. OBJECTIVE: To analyze the subcortical anatomy underlying the ventral part of the precentral gyrus, ie, the ventral precentral fiber intersection area (VPFIA). METHODS: Eight human hemispheres from cadavers were dissected, and 8 healthy hemispheres were studied with diffusion tensor imaging tractography. The tracts that terminate at the ventral part of the precentral gyrus were isolated. In addition, 6 surgical cases with left side gliomas close to the VPFIA were operated awake with intraoperative electrical stimulation mapping. RESULTS: The connections within the VPFIA are anatomically organized along an anteroposterior axis: the pyramidal pathway terminates at the anterior bank of the precentral gyrus, the intermediate part is occupied by the long segment of the arcuate fasciculus, and the posterior bank is occupied by the anterior segment of the arcuate fasciculus. Stimulation of the VPFIA elicited speech arrest in all cases. CONCLUSION: The present study shows strong arguments to sustain that the fiber organization of the VPFIA is different from the classical descriptions, bringing new light for understanding the functional role of this area in language. The VPFIA is a critical neural epicenter within the perisylvian network that may represent the final common network for speech production, as it is strategically located between the termination of the dorsal stream and the motor output cortex that directly control speech muscles.


Assuntos
Lobo Frontal/anatomia & histologia , Substância Branca/anatomia & histologia , Neoplasias Encefálicas/patologia , Imagem de Tensor de Difusão , Glioma/patologia , Humanos , Vias Neurais/anatomia & histologia
8.
World Neurosurg ; 106: 339-354, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28698090

RESUMO

OBJECTIVE: To explore the superior frontal sulcus (SFS) morphology, trajectory of the applied surgical corridor, and white matter bundles that are traversed during the superior frontal transsulcal transventricular approach. METHODS: Twenty normal, adult, formalin-fixed cerebral hemispheres and 2 cadaveric heads were included in the study. The topography, morphology, and dimensions of the SFS were recorded in all specimens. Fourteen hemispheres were investigated through the fiber dissection technique whereas the remaining 6 were explored using coronal cuts. The cadaveric heads were used to perform the superior frontal transsulcal transventricular approach. In addition, 2 healthy volunteers underwent diffusion tensor imaging and tractography reconstruction studies. RESULTS: The SFS was interrupted in 40% of the specimens studied and was always parallel to the interhemispheric fissure. The proximal 5 cm of the SFS (starting from the SFS precentral sulcus meeting point) were found to overlie the anterior ventricular system in all hemispheres. Five discrete white matter layers were identified en route to the anterior ventricular system (i.e., the arcuate fibers, the frontal aslant tract, the external capsule, internal capsule, and the callosal radiations). Diffusion tensor imaging studies confirmed the fiber tract architecture. CONCLUSIONS: When feasible, the superior frontal transsulcal transventricular approach offers a safe and effective corridor to the anterior part of the lateral ventricle because it minimizes brain retraction and transgression and offers a wide and straightforward working corridor. Meticulous preoperative planning coupled with a sound microneurosurgical technique are prerequisites to perform the approach successfully.


Assuntos
Ventrículos Cerebrais/anatomia & histologia , Córtex Pré-Frontal/anatomia & histologia , Substância Branca/anatomia & histologia , Adulto , Cadáver , Ventrículos Cerebrais/diagnóstico por imagem , Corpo Caloso/anatomia & histologia , Corpo Caloso/diagnóstico por imagem , Imagem de Tensor de Difusão , Cápsula Externa/anatomia & histologia , Cápsula Externa/diagnóstico por imagem , Lobo Frontal/anatomia & histologia , Lobo Frontal/diagnóstico por imagem , Voluntários Saudáveis , Humanos , Cápsula Interna/anatomia & histologia , Cápsula Interna/diagnóstico por imagem , Imageamento por Ressonância Magnética , Córtex Pré-Frontal/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
9.
World Neurosurg ; 98: 347-364, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27989972

RESUMO

BACKGROUND: An extensive frontal resection is a frequently performed neurosurgical procedure, especially for treating brain tumor and refractory epilepsy. However, there is a paucity of reports available regarding its surgical anatomy and technique. OBJECTIVES: We sought to present the anatomic landmarks and surgical technique of the frontal lobe decortication (FLD) in epilepsy. The goals were to maximize the gray matter removal, spare primary and supplementary motor areas, and preserve the frontal horn. MATERIAL AND METHODS: The anatomic study was based on dissections performed in 15 formalin-fixed adult cadaveric heads. The clinical experience with 15 patients is summarized. RESULT: FLD consists of 5 steps: 1) coagulation and section of arterial branches of lateral surface; 2) paramedian subpial resection 3 cm ahead of the precentral sulcus to reach the genu of corpus callosum; 3) resection of gray matter of lateral surface, preserving the frontal horn; 4) removal of gray matter of basal surface preserving olfactory tract; 5) removal of gray matter of the medial surface under the rostrum of corpus callosum. The frontal horn was preserved in all 15 patients; 12 patients (80%) had no complications; 2 patients presented temporary hemiparesis; and 1 Rasmussen syndrome patient developed postoperative fever. The best seizure control was in cases with focal magnetic resonance imaging abnormalities limited to the frontal lobe. CONCLUSION: FLD is an anatomy-based surgical technique for extensive frontal lobe resection. It presents reliable anatomic landmarks, selective gray matter removal, preservation of frontal horn, and low complication rate in our series. It can be an alternative option to the classical frontal lobectomy.


Assuntos
Descorticação Cerebral/métodos , Ventrículos Cerebrais/anatomia & histologia , Epilepsia/cirurgia , Lobo Frontal/anatomia & histologia , Lobo Frontal/cirurgia , Psicocirurgia/métodos , Adolescente , Descorticação Cerebral/efeitos adversos , Ventrículos Cerebrais/diagnóstico por imagem , Criança , Pré-Escolar , Epilepsia/diagnóstico por imagem , Feminino , Seguimentos , Lobo Frontal/diagnóstico por imagem , Humanos , Lactente , Masculino , Posicionamento do Paciente/métodos , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Psicocirurgia/efeitos adversos , Adulto Jovem
11.
Paediatr Anaesth ; 26(5): 521-30, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26956994

RESUMO

BACKGROUND: Functional Magnetic Resonance Imaging (fMRI) is often used in preoperative assessment before epilepsy surgery, tumor or cavernous malformation resection, or cochlear implantation. As it requires complete immobility, sedation is needed for uncooperative patients. OBJECTIVE: The aim of this study was to compare the fMRI cortical activation pattern after auditory stimuli in propofol-sedated 5- to 8-year-old children with that of similarly aged nonsedated children. METHODS: When possible, children underwent MRI without sedation, otherwise it was induced with i.v. propofol 2 mg·kg(-1) and maintained with i.v. propofol 4-5 mg·kg(-1) ·h(-1) . Following diagnostic MRI, fMRi was carried out, randomly alternating two passive listening tasks (a fairy-tale and nonsense syllables). RESULTS: We studied 14 awake and 15 sedated children. During the fairy-tale task, the nonsedated children's blood-oxygen-level-dependent (BOLD) signal was bilaterally present in the posterior superior temporal gyrus (STG), Wernicke's area, and Broca's area. Sedated children showed similar activation, with lesser extension to Wernicke's area, and no activation in Broca's area. During the syllable task, the nonsedated children's BOLD signal was bilaterally observed in the STG and Wernicke's area, in Broca's area with leftward asymmetry, and in the premotor area. In sedated children, cortical activation was present in the STG, but not in the frontal lobes. BOLD signal change areas in sedated children were less extended than in nonsedated children during both the fairy-tale and syllable tasks. Modeling the temporal derivative during both the fairy-tale and syllable tasks, nonsedated children showed no response while sedated children did. CONCLUSIONS: After auditory stimuli, propofol-sedated 5- to 8-year-old children exhibit an fMRI cortical activation pattern which is different from that in similarly aged nonsedated children.


Assuntos
Sedação Consciente , Audição/fisiologia , Hipnóticos e Sedativos , Imageamento por Ressonância Magnética/métodos , Propofol , Estimulação Acústica , Criança , Pré-Escolar , Feminino , Lobo Frontal/anatomia & histologia , Lobo Frontal/fisiologia , Humanos , Masculino , Oxigênio/sangue , Lobo Temporal/anatomia & histologia , Lobo Temporal/fisiologia
12.
World Neurosurg ; 89: 309-19, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26875657

RESUMO

OBJECTIVE: The orbitofrontal (or frontobasal) arteries (OFAs) are the medial (MOFA) and lateral (LOFA) orbitofrontal artery, branches of the anterior and middle cerebral artery, respectively. They supply the orbitofrontal cortex. The purpose of this microscopic cadaveric study was the detailed and precise anatomic identification of the OFAs along their course. METHODS: Twenty formalin-fixed, colored latex-injected cadaveric heads were studied with the aid of an operating microscope and microsurgical instrumentation. The anatomy of the OFAs was examined after removing the cerebrum from the cranial vault. Anatomic features of the MOFA and LOFA were investigated and assessed in relation to demographic and anthropometric variables. RESULTS: The MOFA supplies approximately 15 branches and LOFA almost 16 branches. The MOFA provides 1 branch to the olfactory bulb and 4 branches to the olfactory tract, and there are approximately 2 MOFA-LOFA anastomoses per hemisphere (novel finding). The MOFA origin is located approximately 7.9 mm anterior to the anterior communicating artery and 4.7 cm posterior to the anterior limit of the gyrus rectus. The LOFA origin is located approximately 11.1 mm from the middle cerebral artery bifurcation. Younger, shorter, and lighter individuals have more MOFA-LOFA anastomoses. Finally, the number of MOFA branches for the olfactory bulb is positively correlated with the number of MOFA branches for the olfactory tract, as well as with the number of MOFA-LOFA anastomoses. CONCLUSIONS: The present study provides a detailed description of the OFAs' microsurgical anatomy and can help neurosurgeons to easily identify, manipulate, and preserve these vessels during surgery.


Assuntos
Artéria Cerebral Anterior/anatomia & histologia , Artéria Cerebral Média/anatomia & histologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Artéria Cerebral Anterior/cirurgia , Feminino , Formaldeído , Lobo Frontal/anatomia & histologia , Lobo Frontal/irrigação sanguínea , Lobo Frontal/cirurgia , Humanos , Masculino , Microcirurgia , Pessoa de Meia-Idade , Artéria Cerebral Média/cirurgia , Fixação de Tecidos
13.
J Neurol ; 263(1): 157-67, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26559819

RESUMO

The neural correlates of stuttering are to date incompletely understood. Although the possible involvement of the basal ganglia, the cerebellum and certain parts of the cerebral cortex in this speech disorder has previously been reported, there are still not many studies investigating the role of white matter fibers in stuttering. Axonal stimulation during awake surgery provides a unique opportunity to study the functional role of structural connectivity. Here, our goal was to investigate the white matter tracts implicated in stuttering, by combining direct electrostimulation mapping and postoperative tractography imaging, with a special focus on the left frontal aslant tract. Eight patients with no preoperative stuttering underwent awake surgery for a left frontal low-grade glioma. Intraoperative cortical and axonal electrical mapping was used to interfere in speech processing and subsequently provoke stuttering. We further assessed the relationship between the subcortical sites leading to stuttering and the spatial course of the frontal aslant tract. All patients experienced intraoperative stuttering during axonal electrostimulation. On postsurgical tractographies, the subcortical distribution of stimulated sites matched the topographical position of the left frontal aslant tract. This white matter pathway was preserved during surgery, and no patients had postoperative stuttering. For the first time to our knowledge, by using direct axonal stimulation combined with postoperative tractography, we provide original data supporting a pivotal role of the left frontal aslant tract in stuttering. We propose that this speech disorder could be the result of a disconnection within a large-scale cortico-subcortical circuit subserving speech motor control.


Assuntos
Lobo Frontal/anatomia & histologia , Lobo Frontal/fisiopatologia , Gagueira/fisiopatologia , Substância Branca/anatomia & histologia , Substância Branca/fisiopatologia , Adulto , Imagem de Tensor de Difusão , Estimulação Elétrica , Feminino , Seguimentos , Lobo Frontal/cirurgia , Humanos , Monitorização Neurofisiológica Intraoperatória , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Vias Neurais/anatomia & histologia , Vias Neurais/fisiopatologia , Adulto Jovem
14.
Arq. neuropsiquiatr ; 73(11): 934-938, Nov. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-762893

RESUMO

ABSTRACTThe central sulcus region is an eloquent area situated between the frontal and parietal lobes. During neurosurgical procedures, it is sometimes difficult to understand the cortical anatomy of this region.Objective Find alternative ways to anatomically navigate in this region during neurosurgical procedures.Method We analyzed eighty two human hemispheres using a surgical microscope and completed a review of the literature about central sulcus region.Results In 68/82 hemispheres, the central sulcus did not reach the posterior ramus of the lateral sulcus. A knob on the second curve of the precentral gyrus was reliably identified in only 64/82 hemispheres.Conclusion The morphometric data presented in this article can be useful as supplementary method to identify the central sulcus region landmarks.


RESUMOA região do sulco central é uma área eloquente posicionada entre os lobos frontal e parietal. Durante procedimentos neurocirúrgicos, em algumas ocasiões, torna-se difícil compreender a anatomia cortical desta região.Objetivo Encontrar métodos alternativos para uma navegaçāo anatômica desta regiāo durante procedimentos neurocirúrgicos.Método Analisamos oitenta e dois hemisférios humanos usando um microscópio cirúrgico, além de fazer uma revisão da literatura.Resultados Em 68/82 hemisférios, o sulco central não atingiu o ramo posterior do sulco lateral. Uma dilatação na segunda curva do giro precentral foi encontrada em apenas 64/82 hemisférios.Conclusão Os dados morfométricos apresentados neste artigo podem ser úteis como método suplementar para identificação dos reparos anatômicos na região do sulco central.


Assuntos
Humanos , Pontos de Referência Anatômicos/anatomia & histologia , Lobo Frontal/anatomia & histologia , Procedimentos Neurocirúrgicos/métodos , Lobo Parietal/anatomia & histologia , Craniotomia , Imageamento por Ressonância Magnética , Neuroanatomia/métodos , Padrões de Referência
15.
J Anat ; 227(4): 460-73, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26250048

RESUMO

Recent research on the visual system has focused on investigating the relationship among eye (ocular), orbital, and visual cortical anatomy in humans. This issue is relevant in evolutionary and medical fields. In terms of evolution, only in modern humans and Neandertals are the orbits positioned beneath the frontal lobes, with consequent structural constraints. In terms of medicine, such constraints can be associated with minor deformation of the eye, vision defects, and patterns of integration among these features, and in association with the frontal lobes, are important to consider in reconstructive surgery. Further study is therefore necessary to establish how these variables are related, and to what extent ocular size is associated with orbital and cerebral cortical volumes. Relationships among these anatomical components were investigated using magnetic resonance images from a large sample of 83 individuals, which also included each subject's body height, age, sex, and uncorrected visual acuity score. Occipital and frontal gyri volumes were calculated using two different cortical parcellation tools in order to provide a better understanding of how the eye and orbit vary in relation to visual cortical gyri, and frontal cortical gyri which are not directly related to visual processing. Results indicated that ocular and orbital volumes were weakly correlated, and that eye volume explains only a small proportion of the variance in orbital volume. Ocular and orbital volumes were also found to be equally and, in most cases, more highly correlated with five frontal lobe gyri than with occipital lobe gyri associated with V1, V2, and V3 of the visual cortex. Additionally, after accounting for age and sex variation, the relationship between ocular and total visual cortical volume was no longer statistically significant, but remained significantly related to total frontal lobe volume. The relationship between orbital and visual cortical volumes remained significant for a number of occipital lobe gyri even after accounting for these cofactors, but was again found to be more highly correlated with the frontal cortex than with the occipital cortex. These results indicate that eye volume explains only a small amount of variation in orbital and visual cortical volume, and that the eye and orbit are generally more structurally associated with the frontal lobes than they are functionally associated with the visual cortex of the occipital lobes. Results also demonstrate that these components of the visual system are highly complex and influenced by a multitude of factors in humans.


Assuntos
Olho/anatomia & histologia , Lobo Frontal/anatomia & histologia , Lobo Occipital/anatomia & histologia , Órbita/anatomia & histologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Adulto Jovem
16.
Rev. latinoam. enferm ; 23(2): 208-215, Feb-Apr/2015. tab, graf
Artigo em Inglês | LILACS, BDENF - Enfermagem | ID: lil-747165

RESUMO

OBJECTIVE: this study investigated the association of somatic and cognitive-affective symptoms with sex and age, among patients hospitalized with heart disease. METHOD: this study was a secondary analysis of two previous observational studies totaling 531 patients with heart disease, hospitalized from 2005 to 2011 in two public hospitals in Ribeirão Preto, state of São Paulo, Brazil. Somatic and cognitive-affective symptoms were assessed using the subscales of the Beck Depression Inventory - I (BDI-I). RESULTS: of 531 participants, 62.7% were male, with a mean age 57.3 years (SD= 13.0) for males and 56.2 years (SD= 12.1) for females. Analyses of variance showed an effect of sex (p<0.001 for somatic and p=0.005 for cognitive-affective symptoms), but no effect of age. Women presented with higher mean values than men in both BDI-I subscales: 7.1 (4.5) vs. 5.4 (4.3) for somatic, and 8.3 (7.9) vs. 6.7 (7.2) for cognitive-affective symptoms. There were no differences by age for somatic (p=0.84) or cognitive-affective symptoms (p=0.84). CONCLUSION: women hospitalized with heart disease had more somatic and cognitive-affective symptoms than men. We found no association of somatic and cognitive-affective symptoms with age. Future research for these patients could reveal whether these differences according to sex continue throughout the rehabilitation process. .


OBJETIVO: investigar a associação de sintomas somáticos e cognitivo-afetivos ao sexo e à idade de pacientes hospitalizados com doença cardíaca. MÉTODO: este estudo é resultado de uma análise secundária de dois estudos observacionais anteriores, totalizando 531 pacientes com doença cardíaca, internados de 2005 a 2011, em dois hospitais públicos em Ribeirão Preto, estado de São Paulo, Brasil. Os sintomas somáticos e cognitivo-afetivos foram avaliados utilizando-se as subescalas do Inventário de Depressão de Beck - I (IDB-I). RESULTADOS: dos 531 participantes, 62,7% são do sexo masculino, com média de idade de 57,3 anos (DP= 13,0) para os homens e 56,2 anos (DP = 12,1) para as mulheres. A análise da variância mostrou um efeito relacionado ao sexo do paciente (p<0,001 para sintomas somáticos e p=0,005 para os sintomas cognitivo-afetivos), mas nenhum efeito relacionado à idade. As mulheres apresentaram maiores escores do que os homens em ambas subescalas IDB-I: 7,1 (4,5) e 5,4 (4,3) para os sintomas somáticos, e 8,3 (7,9) e 6,7 (7,2) para os sintomas cognitivo-afetivos, respectivamente. Não houve diferenças referentes à idade para sintomas somáticos (p=0,84) ou sintomas cognitivo-afetivos (p=0,84). CONCLUSÃO: as mulheres internadas com doença cardíaca apresentaram mais sintomas somáticos e cognitivo-afetivos do que os homens. Não houve associação dos sintomas somáticos e cognitivo-afetivos com a idade. Pesquisas futuras desses pacientes poderiam revelar se essas diferenças de acordo com o sexo permanecem durante todo o processo de reabilitação. .


OBJETIVO: este estudio investigó la asociación de síntomas somáticos y cognitivo-afectivos con el sexo y la edad en pacientes hospitalizados con enfermedad cardíaca. MÉTODO: este estudio fue un análisis secundario de dos estudios observacionales anteriores, totalizando 531 pacientes con enfermedad cardíaca, internados de 2005 a 2011, en dos hospitales públicos en Ribeirão Preto, estado de São Paulo, Brasil. Los síntomas somáticos y cognitivo-afectivos fueron evaluados utilizándose las subescalas del Inventario Beck de Depresión - I (IBD-I). RESULTADOS: de los 531 participantes, 62,7% era del sexo masculino, con promedio de edad de 57,3 años (DE= 13,0) para los hombres y 56,2 años (DE = 12,1) para el sexo femenino. El análisis de variancia mostró un efecto del sexo (p<0,001 para síntomas somáticos y p=0,005 para los síntomas cognitivo-afectivos), pero ningún efecto de la edad. Las mujeres presentaron valores medios más altos que los hombres en ambas subescalas IBD-I: 7,1 (4,5) vs. 5.4 (4.3) para los síntomas somáticos, y 8,3 (7,9) vs. 6,7 (7,2) para los síntomas cognitivo-afectivos. No fueron encontradas diferencias por edad para síntomas somáticos (p=0,84) o síntomas cognitivo-afectivos (p=0,84). CONCLUSIÓN: las mujeres internadas con enfermedad cardíaca tenían más síntomas somáticos y cognitivo-afectivos que los hombres. No fue encontrada asociación de los síntomas somáticos y cognitivo-afectivos con la edad. Investigaciones futuras de esos pacientes podrían revelar si esas diferencias por sexo continúan durante todo el proceso de rehabilitación. .


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Comportamento do Adolescente/fisiologia , Desenvolvimento do Adolescente/fisiologia , Sistema Límbico/anatomia & histologia , Vias Neurais/anatomia & histologia , Assunção de Riscos , Análise de Variância , Desenvolvimento do Adolescente/efeitos dos fármacos , Mapeamento Encefálico/métodos , Imagem de Tensor de Difusão/métodos , Função Executiva/fisiologia , Seguimentos , Lobo Frontal/anatomia & histologia , Lobo Frontal/fisiologia , Modelos Lineares , Sistema Límbico/fisiologia , Fatores de Risco , Autorrelato , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
17.
Brain Struct Funct ; 220(6): 3399-412, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25086832

RESUMO

Despite a better understanding of their anatomy, the functional role of frontal pathways, i.e., the fronto-striatal tract (FST) and frontal aslant tract (FAT), remains obscure. We studied 19 patients who underwent awake surgery for a frontal glioma (14 left, 5 right) by performing intraoperative electrical mapping of both fascicles during motor and language tasks. Furthermore, we evaluated the relationship between these tracts and the eventual onset of transient postoperative disorders. We also performed post-surgical tract-specific measurements on probabilistic tractography. All patients but one experienced intraoperative inhibition of movement and/or speech during subcortical electrostimulation. On postoperative tractography, the subcortical distribution of stimulated sites corresponded to the spatial course of the FST and/or FAT. Furthermore, we found a significant correlation between postoperative worsening and distances between these tracts and resection cavity. A resection close to the (right or left) FST was correlated with transitory motor initiation disorders (p = 0.026), while a resection close to the left FAT was associated with transient speech initiation disorders (p = 0.003). Moreover, the measurements of average distances between resection cavity and left FAT showed a positive correlation with verbal fluency in both semantic (p = 0.019) and phonemic scores (p = 0.017), while average distances between surgical cavity and left FST showed a positive correlation with verbal fluency scores in both semantic (p = 0.0003) and phonemic modalities (p = 0.037). We suggest that FST and FAT would cooperatively play a role in self-initiated movement and speech, as a part of "negative motor network" involving the pre-supplementary motor area, left inferior frontal gyrus and caudate nucleus.


Assuntos
Corpo Estriado/fisiologia , Movimento/fisiologia , Fala/fisiologia , Adulto , Mapeamento Encefálico/métodos , Neoplasias Encefálicas/fisiopatologia , Neoplasias Encefálicas/cirurgia , Corpo Estriado/cirurgia , Imagem de Tensor de Difusão , Estimulação Elétrica , Feminino , Lobo Frontal/anatomia & histologia , Lobo Frontal/cirurgia , Glioma/fisiopatologia , Glioma/cirurgia , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Neostriado/fisiologia , Vias Neurais/fisiologia , Resultado do Tratamento , Vigília
18.
Neuroimage ; 101: 114-23, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24999039

RESUMO

Prenatal cocaine exposure (PCE) is related to subtle deficits in cognitive and behavioral function in infancy, childhood and adolescence. Very little is known about the effects of in utero PCE on early brain development that may contribute to these impairments. The purpose of this study was to examine brain structural differences in infants with and without PCE. We conducted MRI scans of newborns (mean age = 5 weeks) to determine cocaine's impact on early brain structural development. Subjects were three groups of infants: 33 with PCE co-morbid with other drugs, 46 drug-free controls and 40 with prenatal exposure to other drugs (nicotine, alcohol, marijuana, opiates, SSRIs) but without cocaine. Infants with PCE exhibited lesser total gray matter (GM) volume and greater total cerebral spinal fluid (CSF) volume compared with controls and infants with non-cocaine drug exposure. Analysis of regional volumes revealed that whole brain GM differences were driven primarily by lesser GM in prefrontal and frontal brain regions in infants with PCE, while more posterior regions (parietal, occipital) did not differ across groups. Greater CSF volumes in PCE infants were present in prefrontal, frontal and parietal but not occipital regions. Greatest differences (GM reduction, CSF enlargement) in PCE infants were observed in dorsal prefrontal cortex. Results suggest that PCE is associated with structural deficits in neonatal cortical gray matter, specifically in prefrontal and frontal regions involved in executive function and inhibitory control. Longitudinal study is required to determine whether these early differences persist and contribute to deficits in cognitive functions and enhanced risk for drug abuse seen at school age and in later life.


Assuntos
Encéfalo/efeitos dos fármacos , Líquido Cefalorraquidiano , Cocaína/efeitos adversos , Inibidores da Captação de Dopamina/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Consumo de Bebidas Alcoólicas/efeitos adversos , Encéfalo/anatomia & histologia , Encéfalo/crescimento & desenvolvimento , Cannabis/efeitos adversos , Feminino , Lobo Frontal/anatomia & histologia , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/crescimento & desenvolvimento , Substância Cinzenta/anatomia & histologia , Substância Cinzenta/efeitos dos fármacos , Substância Cinzenta/crescimento & desenvolvimento , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Entorpecentes/efeitos adversos , Gravidez , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Fumar/efeitos adversos
19.
Brain ; 137(Pt 10): 2773-82, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24970097

RESUMO

The organization of basic functions of the human brain, particularly in the right hemisphere, remains poorly understood. Recent advances in functional neuroimaging have improved our understanding of cortical organization but do not allow for direct interrogation or determination of essential (versus participatory) cortical regions. Direct cortical stimulation represents a unique opportunity to provide novel insights into the functional distribution of critical epicentres. Direct cortical stimulation (bipolar, 60 Hz, 1-ms pulse) was performed in 165 consecutive patients undergoing awake mapping for resection of low-grade gliomas. Tasks included motor, sensory, counting, and picture naming. Stimulation sites eliciting positive (sensory/motor) or negative (speech arrest, dysarthria, anomia, phonological and semantic paraphasias) findings were recorded and mapped onto a standard Montreal Neurological Institute brain atlas. Montreal Neurological Institute-space functional data were subjected to cluster analysis algorithms (K-means, partition around medioids, hierarchical Ward) to elucidate crucial network epicentres. Sensorimotor function was observed in the pre/post-central gyri as expected. Articulation epicentres were also found within the pre/post-central gyri. However, speech arrest localized to ventral premotor cortex, not the classical Broca's area. Anomia/paraphasia data demonstrated foci not only within classical Wernicke's area but also within the middle and inferior frontal gyri. We report the first bilateral probabilistic map for crucial cortical epicentres of human brain functions in the right and left hemispheres, including sensory, motor, and language (speech, articulation, phonology and semantics). These data challenge classical theories of brain organization (e.g. Broca's area as speech output region) and provide a distributed framework for future studies of neural networks.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/fisiologia , Lobo Frontal/fisiologia , Adulto , Algoritmos , Anomia/fisiopatologia , Encéfalo/cirurgia , Neoplasias Encefálicas/cirurgia , Córtex Cerebral/anatomia & histologia , Análise por Conglomerados , Craniotomia , Estimulação Elétrica , Feminino , Lobo Frontal/anatomia & histologia , Lateralidade Funcional/fisiologia , Glioma/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Rede Nervosa/fisiologia , Desempenho Psicomotor/fisiologia , Semântica , Fala/fisiologia , Inteligibilidade da Fala/fisiologia
20.
Epilepsy Res ; 108(5): 872-82, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24725809

RESUMO

PURPOSE: The purpose of the current study was to use diffusion tensor imaging (DTI) to conduct tractography of the optic radiations (OR) and its component bundles and to assess both the degree of hemispheric asymmetry and the inter-subject variability of Meyer's Loop (ML). We hypothesized that there are significant left versus right differences in the anterior extent of ML to the temporal pole (TP) in healthy subjects. MATERIALS AND METHODS: DTI data were acquired on a 3T Siemens MRI system using a single-shot Spin Echo EPI sequence. The dorsal, central and ML bundles of the OR were tracked and visualized in forty hemispheres of twenty healthy volunteers. The uncinate fasciculus (UF) was also tracked in these subjects so that it could be used as a distinct anatomical reference. Measurements were derived for the distance between ML-TP, ML and the temporal horn (ML-TH) and ML and the uncinate fasciculus (ML-UF). Paired difference t-tests were carried out with SPSS 14.0. RESULTS: ML and the UF were successfully tracked and visualized in all 20 volunteers. Significant hemispheric asymmetries were found for all measurements with left distances shorter than the right (P<0.005). In 50% of the subjects the left ML-UF distance was ≤1.9 mm. CONCLUSION: The results support our hypothesis and demonstrate that left ML-TP distances are significantly shorter than right ML-TP distances. These asymmetries are also reflected in shorter left distances between ML-TH and ML-UF. Moreover, these results are of interest to left-sided temporal lobe epilepsy surgery because it is not only more likely to disturb the anterior extent of ML but also renders the often closely located posterior aspect of the left UF more vulnerable to potential surgical impact.


Assuntos
Corpos Geniculados/anatomia & histologia , Lobo Temporal/anatomia & histologia , Córtex Visual/anatomia & histologia , Adulto , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Feminino , Lobo Frontal/anatomia & histologia , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador , Sistema Límbico/anatomia & histologia , Masculino , Vias Neurais/anatomia & histologia , Substância Branca/anatomia & histologia , Adulto Jovem
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