Whole-Brain Network Connectivity Underlying the Human Speech Articulation as Emerged Integrating Direct Electric Stimulation, Resting State fMRI and Tractography.

Production of fluent speech in humans is based on a precise and coordinated articulation of sounds. A speech articulation network (SAN) has been observed in multiple brain studies typically using either neuroimaging or direct electrical stimulation (DES), thus giving limited knowledge about the whole brain structural and functional organization of this network. In this study, seven right-handed patients underwent awake surgery resection of low-grade gliomas (4) and cavernous angiomas. We combined pre-surgical resting state fMRI (rs-fMRI) and diffusion MRI together with speech arrest sites obtained intra-operatively with DES to address the following goals: (i) determine the cortical areas contributing to the intrinsic functional SAN using the speech arrest sites as functional seeds for rs-fMRI; (ii) evaluate the relative contribution of gray matter terminations from the two major language dorsal stream bundles, the superior longitudinal fasciculus (SLF III) and the arcuate fasciculus (AF); and (iii) evaluate the possible pre-surgical prediction of SAN with rs-fMRI. In all these right-handed patients the intrinsic functional SAN included frontal, inferior parietal, temporal, and insular regions symmetrically and bilaterally distributed across the two hemispheres regardless of the side (four right) of speech arrest evocation. The SLF III provided a much higher density of terminations in the cortical regions of SAN in respect to AF. Pre-surgical rs-fMRI data demonstrated moderate ability to predict the SAN. The set of functional and structural data provided in this multimodal study characterized, at a whole-brain level, a distributed and bi-hemispherical network subserving speech articulation.

Contralateral approach for far lateral lumbar disc herniations: a modified technique and outcome analysis of nine patients.

STUDY DESIGN: A retrospective analysis of 9 patients who underwent a modified surgical procedure for the treatment of far lateral lumbar disc herniations. OBJECTIVES: To illustrate a modified technique for approaching the neural foramen from the contralateral side, minimizing muscle retraction and bone/ligament resection, and to analyze clinical results. SUMMARY OF BACKGROUND DATA: The most commonly used surgical techniques for the removal of far lateral lumbar disc herniations are ipsilateral approaches, that require partial or complete facet resection and/or intertransverse ligament resection, which may result in vertebral instability and/or chronic back pain. METHODS: Nine patients with intraforaminal or intra/extraforaminal lumbar disc herniation underwent surgery using a modified contralateral approach. There was unilateral muscle retraction and no medial facetectomy nor intertransverse/interspinous ligament resection. Preoperative and postoperative Oswestry functional status evaluation and complications were reviewed and Macnab's postoperative categories were assigned to evaluate the efficacy and safety of the surgery. RESULTS: No serious complications were noted. The mean preoperative and postoperative Oswestry scores were 44 and 14 respectively (P < 0.01). Overall excellent-to-good results were 100%. CONCLUSION: This modified contralateral approach offered a wide exposure of intervertebral foramen region and allowed to remove the herniated disc material with minimal resection of osseous and ligamentous structures. Successful results were achieved in all patients treated by this technique.