Perfusion network shift during seizures in medial temporal lobe epilepsy.

BACKGROUND: Medial temporal lobe epilepsy (MTLE) is associated with limbic atrophy involving the hippocampus, peri-hippocampal and extra-temporal structures. While MTLE is related to static structural limbic compromise, it is unknown whether the limbic system undergoes dynamic regional perfusion network alterations during seizures. In this study, we aimed to investigate state specific (i.e. ictal versus interictal) perfusional limbic networks in patients with MTLE. METHODS: We studied clinical information and single photon emission computed tomography (SPECT) images obtained with intravenous infusion of the radioactive tracer Technetium- Tc 99 m Hexamethylpropyleneamine Oxime (Tc-99 m HMPAO) during ictal and interictal state confirmed by video-electroencephalography (VEEG) in 20 patients with unilateral MTLE (12 left and 8 right MTLE). Pair-wise voxel-based analyses were used to define global changes in tracer between states. Regional tracer uptake was calculated and state specific adjacency matrices were constructed based on regional correlation of uptake across subjects. Graph theoretical measures were applied to investigate global and regional state specific network reconfigurations. RESULTS: A significant increase in tracer uptake was observed during the ictal state in the medial temporal region, cerebellum, thalamus, insula and putamen. From network analyses, we observed a relative decreased correlation between the epileptogenic temporal region and remaining cortex during the interictal state, followed by a surge of cross-correlated perfusion in epileptogenic temporal-limbic structures during a seizure, corresponding to local network integration. CONCLUSIONS: These results suggest that MTLE is associated with a state specific perfusion and possibly functional organization consisting of a surge of limbic cross-correlated tracer uptake during a seizure, with a relative disconnection of the epileptogenic temporal lobe in the interictal period. This pattern of state specific shift in metabolic networks in MTLE may improve the understanding of epileptogenesis and neuropsychological impairments associated with MTLE.

History and current state of neurosurgery at the Medical University of South Carolina.

We review the development of neurosurgery at the Medical University of South Carolina (MUSC) and the emergence of MUSC as a leading academic neurosurgical center in South Carolina. Historical records from the Waring Historical Library were studied, former and current faculty members were interviewed, and the personal records of Dr Phanor J Perot were examined. Dr Frederick E Kredel was the first to perform cerebral revascularization in stroke patients using omental flaps and the first to culture glioma cells in artificial media. The MUSC Neurosurgery residency program was established in 1964 by its first formally trained neurosurgeon, Julian Youmans, MD. The first graduate of the program, Dr Russell Travis, went on to become the President of the American Association of Neurological Surgeons. In 1968, the longest serving chairman, Dr Perot, joined the department and conducted significant research in spinal cord injury, receiving a continuous, 20-year award from the National Institute of Neurological Disorders and Stroke. A major change in the neurosurgery program occurred in 2004 when Dr Sunil Patel accepted the chairmanship. He integrated neurosurgery, neurology, and basic neuroscience departments into a comprehensive Department of Neurosciences to provide integrated clinical care. This department now ranks second in the country in National Institutes of Health research funding. Recently, the Center for Global Health and Global Neurosurgery was established with a vision of caring for patients beyond national borders. Neurosurgery at MUSC has been influenced by Drs Kredel and Perot and the current leadership is moving forward with a uniquely integrated department with novel areas such as global neurosurgery.

Dynamic spring-mediated cranioplasty in a rabbit model.

Since the beginning of craniofacial surgery, there has been an ongoing search for surgical techniques to enhance outcome while, at the same time, decreasing the invasiveness of the surgical treatment of craniofacial deformities. The purpose of this study was to test a recently reported minimally invasive treatment modality, the dynamic spring, in a rabbit calvarial model for efficacy and safety. Specifically, the results of spring cranioplasty on skull growth, the underlying brain, and adjacent bone were to be assessed. The study population consisted of 36 7-week-old New Zealand white rabbits. The rabbits were divided into four treatment groups (9 rabbits each): control, sham surgery, stainless steel springs, and memory metal springs. Postoperative analysis included weekly radiographs to evaluate movement of amalgam markers placed at standardized locations. Additionally, 16 rabbits (4 from each group) were killed at 14 days after surgery, and postmortem histological analysis was done. The remaining rabbits were followed until they were adults and were then killed and similarly analyzed. No morbidity or mortality occurred in the immediate perioperative period secondary to the surgery. Postmortem histological analysis of all study animals revealed no intracranial, subcutaneous, or skin infections and no technical complications related to the surgery. Statistical analysis using ANOVA and pair-wise comparisons between treatment groups revealed a statistically significant difference (P < 0.05) between the marker movement in the spring groups versus the sham and control groups. There were no significant differences between the sham and control groups or between the two spring groups. In conclusion, this study confirms the efficacy and safety of the dynamic spring in a rabbit model.