Essential Subcortical Tracts in Language and Reading. 3D-Tractography for Clinical Practice and Anatomic Correlation with Intraoperative Subcortical Electrostimulation.

Diffusion tensor imaging (DTI) and tractography provide the neurosurgeon with a valid 3D view of the white matter tracts of the brain for the presurgical planning of the treatment of lesions close to eloquent areas, this being one of the principal clinical applications of this technique. In this article, we describe through practical cases the anatomic relationships of white matter tracts that are essential for language and reading, based on DTI studies and the excellent anatomic correlation with the intraoperative subcortical map.

Mapa cortical y subcortical del lenguaje. Correlación de la resonancia magnética funcional y tractografía en 3 T con la estimulación intraoperatoria cortical y subcortical en tumores cerebrales localizados en áreas elocuentes / Cortical and subcortical mapping of language areas: correlation of functional MRI and tractography in a 3 T scanner with intraoperative cortical and subcortical stimulation in patients with brain tumors located in eloquent areas

Objetivo. Describir, con estudios funcionales de activación y tractografía en una RM de 3 Teslas (3 T), las áreas corticales y vías subcorticales implicadas en el lenguaje, y mostrar la buena correlación de estos estudios funcionales con la estimulación directa cortical y subcortical intraoperatoria. Material y métodos. Presentamos una serie de 14 pacientes con lesiones focales cerebrales junto a áreas elocuentes. Todos los pacientes se evaluaron neuropsicológicamente antes y después de la cirugía, se estudiaron con RM con secuencias estructurales, de perfusión, espectroscopia, resonancia magnética funcional y del lenguaje y tractografía 3D, y se sometieron a un mapeo cortical de estimulación cortical y subcortical y resección de la lesión. Se hizo un control posquirúrgico a las 24 h. Resultados. La correlación funcional motora y del haz corticoespinal con el mapeo intraoperatorio cortical y subcortical motor fue completa. Las áreas elocuentes del lenguaje expresivo y del lenguaje receptivo presentaron una alta correlación con el mapeo cortical intraoperatorio en todos los casos menos 2, un glioma infiltrativo de alto grado y un glioma de bajo grado frontal. La tractografía 3D identificó los fascículos arcuato, frontoparietal, subcalloso, frontooccipital inferior y las radiaciones ópticas, lo que permitió marcar los límites de la resección. La correlación con el mapeo subcortical en la disposición anatómica de los fascículos con respecto a las lesiones, fue completa. Conclusión. La máxima resección tumoral sin déficits asociados es el mejor tratamiento posible ante un tumor cerebral, lo que resalta la necesidad de estudios funcionales de alta calidad en la planificación prequirúrgica (AU)

Objective: To describe the detection of cortical areas and subcortical pathways involved in language observed in MRI activation studies and tractography in a 3 T MRI scanner and to corre- late the findings of these functional studies with direct intraoperative cortical and subcortical stimulation. Material and methods: We present a series of 14 patients with focal brain tumors adjacent to eloquent brain areas. All patients underwent neuropsychological evaluation before and after surgery. All patients underwent MRI examination including structural sequences, perfusion imaging, spectroscopy, functional imaging to determine activation of motor and language areas, and 3D tractography. All patients underwent cortical mapping through cortical and subcortical stimulation during the operation to resect the tumor. Postoperative follow-up studies were done 24 hours after surgery. Results: The correlation of motor function and of the corticospinal tract determined by functional MRI and tractography with intraoperative mapping of cortical and subcortical motor areas was complete. The eloquent brain areas of language expression and reception were strongly correlated with intraoperative cortical mapping in all but two cases (a high grade infiltrating glioma and a low grade glioma located in the frontal lobe). 3D tractography identified the arcuate fasciculus, the lateral part of the superior longitudinal fasciculus, the subcallosal fasciculus, the inferior fronto-occipital fasciculus, and the optic radiations, which made it possible to mark the limits of the resection. The correlation with the subcortical mapping of the anatomic arrangement of the fasciculi with respect to the lesions was complete. Conclusion: The best treatment for brain tumors is maximum resection without associated deficits, so high quality functional studies are necessary for preoperative planning (AU)

Cortical and subcortical mapping of language areas: correlation of functional MRI and tractography in a 3T scanner with intraoperative cortical and subcortical stimulation in patients with brain tumors located in eloquent areas.

OBJECTIVE: To describe the detection of cortical areas and subcortical pathways involved in language observed in MRI activation studies and tractography in a 3T MRI scanner and to correlate the findings of these functional studies with direct intraoperative cortical and subcortical stimulation. MATERIAL AND METHODS: We present a series of 14 patients with focal brain tumors adjacent to eloquent brain areas. All patients underwent neuropsychological evaluation before and after surgery. All patients underwent MRI examination including structural sequences, perfusion imaging, spectroscopy, functional imaging to determine activation of motor and language areas, and 3D tractography. All patients underwent cortical mapping through cortical and subcortical stimulation during the operation to resect the tumor. Postoperative follow-up studies were done 24 hours after surgery. RESULTS: The correlation of motor function and of the corticospinal tract determined by functional MRI and tractography with intraoperative mapping of cortical and subcortical motor areas was complete. The eloquent brain areas of language expression and reception were strongly correlated with intraoperative cortical mapping in all but two cases (a high grade infiltrating glioma and a low grade glioma located in the frontal lobe). 3D tractography identified the arcuate fasciculus, the lateral part of the superior longitudinal fasciculus, the subcallosal fasciculus, the inferior fronto-occipital fasciculus, and the optic radiations, which made it possible to mark the limits of the resection. The correlation with the subcortical mapping of the anatomic arrangement of the fasciculi with respect to the lesions was complete. CONCLUSION: The best treatment for brain tumors is maximum resection without associated deficits, so high quality functional studies are necessary for preoperative planning.

[Anterior bulbar compresion with basilar impresion. Surgical management by 2-Piece Le Fort I Transmaxilar Osteotomy]. / Tratamiento quirúrgico de la impresión basilar mediante osteotomía tipo Le Fort I segmentada. A propósito de un caso.

The expansive lesions, whether tumoral or not, originated at the level of the anatomical region of the skull base (SB), show a great histologic variety and clinicaly they cause a variable chronic neurological disfunction. Surgical treatment appears to be the best therapeutic option. An exhaustive knowledge of the topographic anatomy of this area is the mandatory in order to design an appropriate surgical strategy. In many cases, a narrow cooperation with specialists is necesary. As in any other surgical activity, a complete excision of the lesion and an optimal functional and aesthetic rehabilitation, without complications, is the challenge of the surgical team. The approach to the anatomical area of the SB is not single, but is based on a number of procedures, although none of them could be considered the best, or without technical difficulty or any complications. Within the group of transoral approaches, the Le Fort I-Palatal split (LFPS) technique has been considered by different authors an excellent way to approach the clivus and the occipito-vertebral joint. We report the case of a patient, treated in cooperation with the Department of Neurosurgery of our hospital. He was clinical and radiologically diagnosed of basilar impresion with bulbar compression, and the MRI revealed the presence of a located extradural fibrous injury above the odontoid apophysis. Therefore we chose the use of a LFPS to approach this lesion. With an optimal surgical field, a complete excision of the lesion was obtained. The postoperatory result in the subsequent follow-up was highly satisfactory.

Tratamiento quirúrgico de la impresión basilar mediante osteotomía tipo Le Fort I segmentada. A propósito de un caso / Anterior bulbar compresion with basilar impresion. Surgical management by 2-Piece Le Fort I transmaxilar osteotomy

La patología de carácter expansivo, tumoral o no, originada a nivel de la región anatómica de la base del cráneo (BC), presenta una gran diversidad histológica; desde un punto de vista clínico provoca una disfunción neurológica crónica de mayor o menor gravedad. El tratamiento quirúrgico representa la opción terapéutica más empleada. Un conocimiento exhaustivo de la anatomía topográfica de esta área es prioritario para un correcto diseño de la estrategia operatoria. En muchos casos se requiere una estrecha colaboración multidisciplinar. Como en cualquier actividad quirúrgica, la exéresis lesional completa y una correcta rehabilitación funcional y estética, en ausencia de complicaciones, es el reto del equipo quirúrgico. El abordaje a la encrucijada anatómica que constituye la BC no es único, si no que se sustenta en un gran abanico de posibilidades; ninguna vía se puede considerar la mejor, ni ninguna está exenta de dificultad técnica, ni de posibles complicaciones. Dentro del grupo de las vías transorales, la osteotomía maxilar tipo Le Fort I (OMLF I) segmentado, es aceptada por distintos autores como una excelente posibilidad de abordaje a la región del clivus y de la charnela occipito-vertebral. Presentamos el caso de un paciente, tratado de forma conjunta con el Servicio de Neurocirugía de nuestro hospital. Fue diagnosticado clínica y radiológicamente de impresión basilar con compresión bulbar. El estudio de imagen mediante Resonancia Magnética (RM) ponía de manifiesto la presencia de un lesión fibrosa extradural localizada alrededor de la apófisis odontoides. En sesión clínica conjunta se decidió emplear un abordaje mediante OMLF I segmentado para abordar dicha lesión. La exposición del lecho quirúrgico fue óptima, obteniéndose una resección completa. Los resultados postoperatorios fueron altamente satisfactorios (AU)

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