Hypoglossal Nerve Injury With C1 Lateral Mass Screw Placement: A Case Report and Review of the Literature

We report the case of a 62-year-old man who presented with a progressive myelopathy secondary to spinal cord compression from an odontoid process fracture and subaxial central canal stenosis. The patient underwent a C1-T2 posterior decompression and instrumented fusion (PCDF) and did well immediately postoperatively. However, on POD1, he developed a right hypoglossal nerve (HN) palsy attributed to direct mechanical compression or injury from the C1 lateral mass screw (LMS), which improved following a revision and screw replacement. While HN injury is a known complication of high anterior and anterolateral cervical spine approaches as well as transcondylar screw fixation, this case aims to expand on the limited reports available regarding hypoglossal nerve injury following placement of bicortical C1 LMS. Furthermore, the use of fluoroscopic guidance in addition to anatomic landmarks and triggered electromyography of the tongue are offered as potential solutions to prevent HN injury intraoperatively

Neuromodulation in the Age of Modern Neuroimaging Technologies

Most commonly used for the treatment of Parkinson’s disease (PD), the deep brain stimulation (DBS) is a new neurosurgical method whose other applications are still under development. Neuroimaging has a variety of main roles in DBS including evaluating the final electrode contact position, localizing the target nucleus, and detecting complications. Despite being a neurosurgical method, successful DBS intervention is highly dependent on an appropriate neuroimaging technique. For achieving satisfying clinical results, DBS needs the presence of neuroradiologists. In this chapter, we have reviewed the role of neuroimaging in all stages of deep brain stimulation as well as the underlying mechanism in this domain

Full Issue: Volume 13, Issue 1 - Winter 2018

Full Issue: Volume 13, Issue 1 - Winter 201

Injury induced neuroplasticity and cell specific targeting of the lumbar enlargement for gene therapy.

This dissertation is an examination of spinal cord injury induced neuroplasticity and tests whether noninvasive gene therapy can successfully target neurons in the lumbar spinal cord. It begins with an overview of neural control of locomotion and a brief summary of therapeutics that are used and/or in development for treating spinal anatomically characterize s subset of neurons in the spinal cord, long ascending propriospinal neurons, that are involved in interlimb coordination. Characterization of these neurons allows for subsequent evaluation of their potential involvement in injury induced neuroplasticity. This dissertation is divided into five chapters, covering spinal cord injury and therapeutics. Chapter One gives background on locomotor control, propriospinal neurons, spinal cord injury, and therapeutics. Chapter Two develops and characterizes viral tracing methods for spinal cord anatomy. Chapter Three then uses these methods to characterize long ascending propriospinal neurons and evaluate their involvement in injury induced plasticity. Chapter Four then focuses on the development of noninvasive delivery of gene transfer to the lumbar enlargement. This involves optimizing focused ultrasound and intravenous microbubble delivery to focally and transiently permeabilize the blood spinal cord barrier of the lumbar spinal cord. This optimization then allows for successful gene transfer in neurons in the lumbar spinal cord following intravenous delivery of viral vector. Lasty, Chapter Five discusses the implications for all of these findings and how these findings have contributed to our understanding spinal cord anatomy and injury, and how the proof-of-concept in Chapter 4 provides a promising new avenue for spinal cord injury therapeutics

Development of a patient-specific atrial phantom model for planning and training of inter-atrial interventions

Article is accepted for publicationBackgroundSeveral authors have presented cardiac phantoms to mimic the particularities of the heart, making it suitable for medical training and surgical planning. Although the initial models were mainly focused on the ventricles, personalized phantoms of the atria were recently presented. However, such models are typically rigid, the atrial wall is not realistic and they are not compatible with ultrasound (US), being sub-optimal for planning/training of several interventions. MethodsIn this work, we propose a strategy to construct a patient-specific atrial model. Specifically, the target anatomy is generated using a computed tomography (CT) dataset and then constructed using a mold-cast approach. An accurate representation of the inter-atrial wall (IAS) was ensured during the model generation, allowing its application for IAS interventions. Two phantoms were constructed using different flexible materials (silicone and polyvinyl alcohol cryogel, PVA-C), which were then compared to assess their appropriateness for US acquisition and for the generation of complex anatomies. ResultsTwo experiments were set up to validate the proposed methodology. First, the accuracy of the manufacturing approach was assessed through the comparison between a post-production CT and the virtual references. The results proved that the silicone-based model was more accurate than the PVA-C-based one, with an error of 1.680.79, 1.36 +/- 0.94, 1.45 +/- 0.77mm for the left (LA) and right atria (RA) and IAS, respectively. Second, an US acquisition of each model was performed and the obtained images quantitatively and qualitatively assessed. Both models showed a similar performance in terms of visual evaluation, with an easy detection of the LA, RA, and the IAS. Furthermore, a moderate accuracy was obtained between the atrial surfaces extracted from the US and the ideal reference, and again a superior performance of the silicone-based model against the PVA-C phantom was observed. ConclusionsThe proposed strategy proved to be accurate and feasible for the correct generation of complex personalized atrial models.The authors acknowledge "Fundacao para a Ciencia e a Tecnologia" (FCT), in Portugal, and the European Social Found, European Union, for funding support through the "Programa Operacional Capital Humano" (POCH) in the scope of the PhD grants SFRH/BD/95438/2013 (P. Morais) and SFRH/BD/93443/2013 (S. Queiros).Authors gratefully acknowledge the funding of Projects NORTE-01-0145-FEDER-000013 and NORTE-01-0145-FEDER-000022, cofinanced by "Programa Operacional Regional do Norte" (NORTE2020), through "Fundo Europeu de Desenvolvimento Regional" (FEDER).info:eu-repo/semantics/publishedVersio