Subthalamic Beta Activity in Parkinson's Disease May Be Linked to Dorsal Striatum Gray Matter Volume and Prefrontal Cortical Thickness: A Pilot Study.

Background: Excessive oscillations at beta frequencies (13-35 Hz) in the subthalamic nucleus (STN) represent a pathophysiological hallmark of Parkinson's disease (PD), which correlates well with parkinsonian symptoms and is reduced in response to standard disease treatments. However, the association of disease-specific regional gray matter (GM) atrophy or cortical thickness (CT) with the presence of STN beta oscillatory activity has been poorly investigated but is of relevance given the potential of these variables for extracting information about PD pathophysiology. This exploratory study investigated the involvement of regional GM volume and CT in the basal ganglia-cortical network and its potential association with the presence of STN beta oscillatory activity in PD. Methods: We acquired preoperative GM densities on T1-weighted magnetic resonance imaging scans and we carried out regional estimation of GM volume and CT. LFP activities from the STN were recorded post-operatively in 7 cognitively preserved PD patients off dopaminergic medication undergoing deep-brain stimulation surgery. Oscillatory beta power was determined by power spectral density of 4-min resting state STN LFP activity. Spearman partial correlations and regression analysis were used to screen the presence of STN beta power for their relationship with GM volume and CT measurements. Results: After controlling for the effects of age, educational level, and disease duration, and after correcting for multiple testing, enhanced STN beta power showed significant and negative correlations between, first, volume of the right putamen and left caudate nucleus, and second, smaller CT in frontal regions involving the left rostral middle frontal gyrus (MFG) and left medial orbitofrontal gyrus. A lower volume in the right putamen and a lower CT in the left MFG demonstrated the strongest associations with increased STN beta power. Conclusions: These tentative results seem to suggest that STN LFP beta frequencies may be mainly linked to different but ongoing parallel neurodegenerative processes, on the one hand, to GM volume reduction in dorsal striatum, and on the other hand, to CT reduction of prefrontal-"associative" regions. These findings could further delineate the brain structural interactions underpinning the exaggerated STN beta activity commonly observed in PD patients.

Spinal dural closure without suture: Minimizing the risk of CSF leakage with a flat non-penetrating titanium U-clip / Cierre dural espinal sin sutura: minimizando el riesgo de fístula de LCR con U-Clip(R) de titanio no penetrante plano

Background: The classic surgical spinal dural closure technique in surgery on intradural lesions is performed with continuous suture or loose stitches using 4-0 to 6-0 polypropylene monofilament or nylon suture. Dural closure with suture causes irritant damage to the dural/arachnoid interface. The penetrating suture causes new dural holes. Even the needle of the suture can cause harm to the patient and the surgeon. For these reasons, other non-penetrating techniques for dural closure have been sought. Objective: The purpose of this review was to show the efficacy of using the titanium clip (U-clip) (Ligaclip-MCA of Ethicon Endo-Surgery, LLC, Medical GmbH, Norderstedt, Germany) with a flat internal surface in spinal neurosurgical procedures, and to evaluate the effects of its use on post-operative magnetic resonance imaging (MRI). Methods: We performed a retrospective analysis of a cohort of 50 consecutive patients who underwent intradural spinal surgeries for intradural spinal lesions in the neurosurgery department of our institution between 2013 and 2018. Results: The mean follow-up period was 27 months. No patient developed a post-operative cerebrospinal fluid (CSF) dural-cutaneous fistula. CSF leakage was not observed in the control MRIs at 6 weeks. Conclusions: We describe, for the first time, the use of this type of U-clip with a flat inner side. The non-penetrating titanium U-clip facilitates effective and rapid dural closure at all spinal levels due to its flat internal face when closed. The U-clips did not cause significant artefacts or distortions on the magnetic resonance imaging

Introducción: La técnica quirúrgica clásica de cierre de la duramadre espinal en cirugía en lesiones intradurales se realiza con sutura continua o puntos sueltos usando monofilamento de polipropileno 4-0 a 6-0 o sutura de nylon. El cierre dural con sutura causa daño irritante a la interfaz dural/aracnoidea. La sutura penetrante causa nuevos agujeros durales. Incluso la aguja de la sutura puede causar daño al paciente y al cirujano. Por estas razones, se han buscado otras técnicas no penetrantes para el cierre de la duramadre. Objetivo: El propósito de esta revisión fue mostrar la eficacia del uso del clip de titanio (U-Clip(R)) (Ligaclip MCA de Ethicon Endo-Surgery, LLC, Medical GmbH, Norderstedt, Alemania) con una superficie interna plana en procedimientos neuroquirúrgicos espinales, y para evaluar los efectos de su uso en los controles de resonancia magnética (RM) postoperatoria. Métodos: Se realizó un análisis retrospectivo de una cohorte de 50 pacientes consecutivos que se sometieron a cirugías intradurales espinales en el departamento de neurocirugía de nuestra institución entre 2013 y 2018. Resultados: El período medio de seguimiento fue de 27 meses. Ningún paciente desarrolló fístula dural-cutánea del líquido cefalorraquídeo (LCR) postoperatoria. No se observó fuga del LCR en las RM de control a las 6 semanas. Conclusiones: Describimos, por primera vez, el uso de este tipo U-Clip(R) con un lado interior plano. El U-Clip(R) de titanio no penetrante facilita el cierre dural efectivo y rápido en todos los niveles espinales debido a su cara interna plana cuando está cerrado. Los U-Clip(R) no causaron artefactos o distorsiones significativas en la RM

Meningioma intramedular tipo rabdoide. Reporte de un caso y revisión de la literatura / Rhabdoid type intramedullary meningioma. A case report and review of the literature

Los meningiomas son los tumores más frecuentes localizados a nivel espinal junto a neurinomas y metástasis. Estos tumores suelen ser intradurales y extramedular. Son pocos los casos descritos en la literatura con una localización puramente intramedular (menos de 10 casos) y frecuentemente se observan en la unión cráneo-cervical. Ante la presencia de un tumor intramedular, realizamos diagnósticos diferenciales con ependimomas, astrocitomas, etc. En este artículo presentamos el primer caso descrito en la literatura de un paciente con un meningioma tipo rabdoide exclusivamente intramedular a nivel del cono medular

Meningiomas are the most frequent tumors located at the spinal level together with neurinomas and metastases. These tumors tend to be intradural and extramedullar. There are few cases described in the literature with a purely intramedullary location (less than 10 cases) and they are frequently observed in the union craneal-cervical. In the presence of an intramedullary tumor we perform differential diagnoses with ependymomas, astrocytomas... In this article we present the first case described in the literature of a patient with a rabdoid-type meningioma exclusively intramedullary at the level of the medullary cone

Rhabdoid type intramedullary meningioma. A case report and review of the literature. / Meningioma intramedular tipo rabdoide. Reporte de un caso y revisión de la literatura.

Meningiomas are the most frequent tumors located at the spinal level together with neurinomas and metastases. These tumors tend to be intradural and extramedullar. There are few cases described in the literature with a purely intramedullary location (less than 10 cases) and they are frequently observed in the union craneal-cervical. In the presence of an intramedullary tumor we perform differential diagnoses with ependymomas, astrocytomas... In this article we present the first case described in the literature of a patient with a rabdoid-type meningioma exclusively intramedullary at the level of the medullary cone.