Posts Tagged ‘tumor’
Background: Recent findings associated with resting state cortical networks have provided insight into the brain’s organizational structure. In addition to their neuroscientific implications, the networks identified by resting state functional MRI (rs-fMRI) may prove useful for clinical brain mapping.
Objective: To demonstrate that a data-driven approach to analyze resting state networks is useful in identifying regions classically understood to be eloquent cortex as well as other functional networks.
Methods: Study included six subjects undergoing surgical treatment for intractable epilepsy and seven subjects undergoing tumor resection. rs-fMRI data were obtained prior to surgery and seven canonical resting state networks (RSNs) were identified by an artificial neural network algorithm. Of these seven, the motor and language networks were then compared to electrocortical stimulation as the gold standard in the epilepsy patients. The sensitivity and specificity for identifying these eloquent sites was calculated at varying thresholds, which yielded receiver operating characteristic (ROC) curves and their associated area under the curve (AUC). RSN networks were plotted in the tumor subjects to observe RSN distortions in altered anatomy.
Background: Awake craniotomy (AC) for removal of intra-axial brain tumors is a well-established procedure. However, the occurrence and consequences of intraoperative seizures during AC have not been well characterized.
Objective: To analyze the incidence, risk factors, and consequences of seizures during AC.
Methods: The database of AC at Tel Aviv Medical Center between 2003 to 2011 was reviewed. Occurrences of intraoperative seizures were analyzed with respect to medical history, medications, tumor characteristics, and postoperative outcome.
Background: Navigated transcranial magnetic stimulation (nTMS) is increasingly used in presurgical brain mapping. Preoperative nTMS results correlate well with direct cortical stimulation (DCS) data in the identification of the primary motor cortex. Repetitive nTMS can also be used for mapping of speech-sensitive cortical areas.
Objective: The current cohort study compares the safety and effectiveness of preoperative nTMS with DCS mapping during awake surgery for the identification of language areas in patients with left-sided cerebral lesions.
Methods: Twenty patients with tumors in or close to left-sided language eloquent regions were examined by repetitive nTMS before surgery. During awake surgery, language-eloquent cortex was identified by DCS. nTMS results were compared for accuracy and reliability with regard to DCS by projecting both results into the cortical parcellation system.
Background: Jugular foramen tumors are rare and challenging lesions for skull base surgeons due to their difficult operative accessibility. Various surgical approaches to the jugular foramen have been described to overcome the morbidity of standard petrosectomy.
Objective: To describe the surgical anatomy of a novel route to the jugular foramen without opening the fallopian canal: the navigated tailored presigmoidal suprabulbar infralabyrinthine approach.
Methods: Ten cadaver heads were dissected under navigational guidance on both sides to examine the advantages and limitations of the presigmoidal suprabulbar infralabyrinthine approach without opening the fallopian canal. Mastoidectomy was performed using a high-speed drill. Under navigation guidance, the sigmoid sinus, jugular bulb, posterior semicircular canal, and fallopian canal were located and preserved. The jugular foramen with the extradural part of the IXth, Xth, and XIth nerve were identified.