Browsing by Author "Department of Neurological Surgery, IU School of Medicine"

Now showing 1 - 10 of 48
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    Assessment of white matter loss using bond-selective photoacoustic imaging in a rat model of contusive spinal cord injury
    (Mary Ann Liebert, 2014-12-15) Wu, Wei; Wang, Pu; Cheng, Ji-Xin; Xu, Xiao-Ming; Department of Neurological Surgery, IU School of Medicine
    White matter (WM) loss is a critical event after spinal cord injury (SCI). Conventionally, such loss has been measured with histological and histochemical approaches, although the procedures are complex and may cause artifact. Recently, coherent Raman microscopy has been proven to be an emerging technology to study de- and remyelination of the injured spinal cord; however, limited penetration depth and small imaging field prevent it from comprehensive assessments of large areas of damaged tissues. Here, we report the use of bond-selective photoacoustic (PA) imaging with 1730-nm excitation, where the first overtone vibration of CH2 bond is located, to assess WM loss after a contusive SCI in adult rats. By employing the first overtone vibration of CH2 bond as the contrast, the mapping of the WM in an intact spinal cord was achieved in a label-free three-dimensional manner, and the physiological change of the spinal cord before and after injury was observed. Moreover, the recovery of the spinal cord from contusive injury with the treatment of a neuroprotective nanomedicine ferulic-acid-conjugated glycol chitosan (FA-GC) was also observed. Our study suggests that bond-selective PA imaging is a valuable tool to assess the progression of WM pathology after SCI as well as neuroprotective therapeutics in a label-free manner.
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    Automated monitoring of early neurobehavioral changes in mice following traumatic brain injury
    (Medknow Publications, 2016-02) Qu, Wenrui; Liu, Nai-Kui; Xie, Xin-Min Simon; Li, Rui; Xu, Xiao-Ming; Department of Neurological Surgery, IU School of Medicine
    Traumatic brain injury often causes a variety of behavioral and emotional impairments that can develop into chronic disorders. Therefore, there is a need to shift towards identifying early symptoms that can aid in the prediction of traumatic brain injury outcomes and behavioral endpoints in patients with traumatic brain injury after early interventions. In this study, we used the SmartCage system, an automated quantitative approach to assess behavior alterations in mice during an early phase of traumatic brain injury in their home cages. Female C57BL/6 adult mice were subjected to moderate controlled cortical impact (CCI) injury. The mice then received a battery of behavioral assessments including neurological score, locomotor activity, sleep/wake states, and anxiety-like behaviors on days 1, 2, and 7 after CCI. Histological analysis was performed on day 7 after the last assessment. Spontaneous activities on days 1 and 2 after injury were significantly decreased in the CCI group. The average percentage of sleep time spent in both dark and light cycles were significantly higher in the CCI group than in the sham group. For anxiety-like behaviors, the time spent in a light compartment and the number of transitions between the dark/light compartments were all significantly reduced in the CCI group than in the sham group. In addition, the mice suffering from CCI exhibited a preference of staying in the dark compartment of a dark/light cage. The CCI mice showed reduced neurological score and histological abnormalities, which are well correlated to the automated behavioral assessments. Our findings demonstrate that the automated SmartCage system provides sensitive and objective measures for early behavior changes in mice following traumatic brain injury.
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    Bacterial Infections of the Central Nervous System
    (Lippincott, Williams, and Wilkins, 2015-12) Roos, Karen L.; Department of Neurological Surgery, IU School of Medicine
    Purpose of Review:: Bacterial infections of the central nervous system are neurologic emergencies. Prompt recognition and treatment are essential not only to prevent mortality, but also to decrease neurologic sequelae. This article focuses on the two most common central nervous system bacterial infections, bacterial meningitis and spinal epidural abscess. Recent Findings:: Two outbreaks of serogroup B meningococcal disease have occurred on US college campuses. The meningococcal vaccine given to young adults does not contain serogroup B. Summary:: In bacterial meningitis and in bacterial spinal epidural abscess, the identification of and eradication of the pathogen with antimicrobial therapy is the easy part. It is the recognition of the disorder, the understanding of which diagnostic studies to obtain and their limitations, and the management of the neurologic complications that require the expertise of a neurologist.
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    Biphasic bisperoxovanadium administration and Schwann cell transplantation for repair after cervical contusive spinal cord injury
    (Elsevier, 2015-02) Walker, Chandler L.; Wang, Xiaofei; Bullis, Carli; Liu, Nai-Kui; Lu, Qingbo; Fry, Colin; Deng, Lingxiao; Xu, Xiao-Ming; Department of Neurological Surgery, IU School of Medicine
    Schwann cells (SCs) hold promise for spinal cord injury (SCI) repair; however, there are limitations for its use as a lone treatment. We showed that acute inhibition of the phosphatase and tensin homolog deleted on chromosome ten (PTEN) by bisperoxovanadium (bpV) was neuroprotective and enhanced function following cervical hemicontusion SCI. We hypothesized that combining acute bpV therapy and delayed SC engraftment would further improve neuroprotection and recovery after cervical SCI. Adult female Sprague-Dawley (SD) rats were randomly sorted into 5 groups: sham, vehicle, bpV, SC transplantation, and bpV+SC transplantation. SCs were isolated from adult green fluorescent protein (GFP)-expressing SD rats (GFP-SCs). 200 μg/kg bpV(pic) was administered intraperitoneally (IP) twice daily for 7 days post-SCI in bpV-treated groups. GFP-SCs (1×10(6) in 5 μl medium) were transplanted into the lesion epicenter at the 8th day post-SCI. Forelimb function was tested for 10 weeks and histology was assessed. bpV alone significantly reduced lesion (by 40%, p<0.05) and cavitation (by 65%, p<0.05) and improved functional recovery (p<0.05) compared to injury alone. The combination promoted similar neuroprotection (p<0.01 vs. injury); however, GFP-SCs alone did not. Both SC-transplanted groups exhibited remarkable long-term SC survival, SMI-31(+) axon ingrowth and RECA-1(+) vasculature presence in the SC graft; however, bpV+SCs promoted an 89% greater axon-to-lesion ratio than SCs only. We concluded that bpV likely contributed largely to the neuroprotective and functional benefits while SCs facilitated considerable host-tissue interaction and modification. The combination of the two shows promise as an attractive strategy to enhance recovery after SCI.
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    Blood Supply to the Human Spinal Cord. I. Anatomy and Hemodynamics
    (Wiley, 2015-01) Bosmia, Anand N.; Hogan, Elizabeth; Loukas, Marios; Tubbs, R. Shane; Cohen-Gadol, Aaron A.; Department of Neurological Surgery, IU School of Medicine
    The arterial network that supplies the human spinal cord, which was once thought to be similar to that of the brain, is in fact much different and more extensive. In this article, the authors attempt to provide a comprehensive review of the literature regarding the anatomy and known hemodynamics of the blood supply to the human spinal cord. Additionally, as the medical literature often fails to provide accurate terminology for the arteries that supply the cord, the authors attempt to categorize and clarify this nomenclature. A complete understanding of the morphology of the arterial blood supply to the human spinal cord is important to anatomists and clinicians alike.
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    Blood Supply to the Human Spinal Cord. II. Imaging and Pathology
    (Wiley, 2015-01) Bosmia, Anand N.; Tubbs, R. Shane; Hogan, Elizabeth; Bohnstedt, Bradley N.; DeNardo, Andrew J.; Loukas, Marios; Cohen-Gadol, Aaron A.; Department of Neurological Surgery, IU School of Medicine
    The blood supply of the spinal cord is a complex system based on multilevel sources and anastomoses. Diseases often affect this vascular supply and imaging has been developed that better investigates these structures. The authors review the literature regarding pathology and imaging modalities for the blood supply of the spinal cord. Knowledge of the disease processes and imaging modalities used to investigate these arterial lesions of the spinal cord will assist the clinician when treating patients with spinal cord lesions.
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    Breaking news in spinal cord injury research: FDA approved phase I clinical trial of human, autologous schwann cell transplantation in patients with spinal cord injuries
    (Wanfang Med Online, 2012-08-05) Xu, Xiao-Ming; Department of Neurological Surgery, IU School of Medicine
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    Choroid Plexus of the Fourth Ventricle: Review and Anatomic Study Highlighting Anatomical Variations
    (Elsevier, 2016-04) Tubbs, R. Shane; Shoja, Mohammadali M.; Aggarwal, Anjali; Gupta, Tulika; Loukas, Marios; Sahni, Daisy; Ansari, Shaheryar F.; Cohen-Gadol, Aaron A.; Department of Neurological Surgery, IU School of Medicine
    Relatively few studies have been performed that analyze the morphology of the choroid plexus of the fourth ventricle. Due to the importance of this tissue as a landmark on imaging and during surgical intervention of the fourth ventricle, the authors performed a cadaveric study to better characterize this important structure. The choroid plexus of the fourth ventricle of 60 formalin fixed adult human brains was examined and measured. The horizontal distance from the midline to the lateral most point of the protruding tip of the horizontal limbs was measured. In the majority of the 60 brain specimens, right and left horizontal limbs of the choroid plexus were seen extending from the midline and protruding out of their respective lateral apertures of the fourth ventricle and into the subarachnoid space. However, on 3.3% of sides, there was absence of an extension into the foramen of Luschka and in one specimen, this lack of extension into the foramen of Luschka was bilateral. On two sides, there was discontinuity between the midline choroid plexus and the tuft of choroid just outside the foramen of Luschka. For specimens in which the choroid plexus did protrude through the foramen of Luschka (96.7%), these tufts were located anterior to the flocculus and inferolateral to the facial/vestibulocochlear nerve complex and posterosuperior to the glossopharyngeal/vagal/accessory complex. A thorough understanding of the normal and variant anatomy of the fourth ventricular choroid plexus is necessary for those who operate in, or interpret imaging of, this region.
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    Clip ligation of contralateral P1 aneurysm: extending the working depth of microsurgery along the skull base
    (2015-01) Rupani, Karishma Vijay; Cohen-Gadol, Aaron A.; Department of Neurological Surgery, IU School of Medicine
    Clip ligation of posterior circulation aneurysms can be challenging because of limited operative working space and angles. Certain proximal posterior cerebral (P1) aneurysms are especially challenging because of their locations within the lateral anterior interpeduncular fossa. We present a 52-year-old woman who had previously undergone coil embolization of a ruptured right-sided posterior communicating artery aneurysm. She also had two other small aneurysms (left posterior communicating artery and right P1 aneurysms). She underwent clip ligation of the latter two unruptured aneurysms through a left-sided pterional craniotomy. The microsurgical techniques to clip ligate a contralateral P1 aneurysm are discussed in the video. The video can be found here: http://youtu.be/YBE7FcFGlpQ.
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    Cognitive Impairment Precedes and Predicts Functional Impairment in Mild Alzheimer’s Disease
    (IOS, 2015-07) Liu-Seifert, Hong; Siemers, Eric; Price, Karen; Han, Baoguang; Selzler, Katherine J.; Henley, David; Sundell, Karen; Aisen, Paul; Cummings, Jeffrey; Raskin, Joel; Mohs, Richard; Department of Neurological Surgery, IU School of Medicine
    Abstract Background: The temporal relationship of cognitive deficit and functional impairment in Alzheimer’s disease (AD) is not well characterized. Recent analyses suggest cognitive decline predicts subsequent functional decline throughout AD progression. Objective: To better understand the relationship between cognitive and functional decline in mild AD using autoregressive cross-lagged (ARCL) panel analyses in several clinical trials. Methods: Data included placebo patients with mild AD pooled from two multicenter, double-blind, Phase 3 solanezumab (EXPEDITION/2) or semagacestat (IDENTITY/2) studies, and from AD patients participating in the Alzheimer’s Disease Neuroimaging Initiative (ADNI). Cognitive and functional outcomes were assessed using AD Assessment Scale-Cognitive subscale (ADAS-Cog), AD Cooperative Study-Activities of Daily Living instrumental subscale (ADCS-iADL), or Functional Activities Questionnaire (FAQ), respectively. ARCL panel analyses evaluated relationships between cognitive and functional impairment over time. Results: In EXPEDITION, ARCL panel analyses demonstrated cognitive scores significantly predicted future functional impairment at 5 of 6 time points, while functional scores predicted subsequent cognitive scores in only 1 of 6 time points. Data from IDENTITY and ADNI programs yielded consistent results whereby cognition predicted subsequent function, but not vice-versa. Conclusions: Analyses from three databases indicated cognitive decline precedes and predicts subsequent functional decline in mild AD dementia, consistent with previously proposed hypotheses, and corroborate recent publications using similar methodologies. Cognitive impairment may be used as a predictor of future functional impairment in mild AD dementia and can be considered a critical target for prevention strategies to limit future functional decline in the dementia process.