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Reynolds BB, By S, Weinberg QR, Witt AA, Newton AT, Feiler HR, Ramkorun B, Clayton DB, Couture P, Martus JE, Adams M, Wellons JC, Smith SA, Bhatia A. Quantification of DTI in the Pediatric Spinal Cord: Application to Clinical Evaluation in a Healthy Patient Population. AJNR Am J Neuroradiol 2019; 40:1236-1241. [PMID: 31196859 PMCID: PMC7048550 DOI: 10.3174/ajnr.a6104] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 05/16/2019] [Indexed: 12/18/2022]
Abstract
BACKGROUND AND PURPOSE The purpose of the study is to characterize diffusion tensor imaging indices in the developing spinal cord, evaluating differences based on age and cord region. Describing the progression of DTI indices in the pediatric cord increases our understanding of spinal cord development. MATERIALS AND METHODS A retrospective analysis was performed on DTI acquired in 121 pediatric patients (mean, 8.6 years; range, 0.3-18.0 years) at Monroe Carell Jr. Children's Hospital at Vanderbilt from 2017 to 2018. Diffusion-weighted images (15 directions; b = 750 s/mm2; slice thickness, 5 mm; in-plane resolution, 1.0 × 1.0 mm2) were acquired on a 3T scanner in the cervicothoracic and/or thoracolumbar cord. Manual whole-cord segmentation was performed. Images were masked and further segmented into cervical, upper thoracic, thoracolumbar, and conus regions. Analyses of covariance were performed for each DTI-derived index to investigate how age affects diffusion across cord regions, and 95% confidence intervals were calculated across age for each derived index and region. Post hoc testing was performed to analyze regional differences. RESULTS Analyses of covariance revealed significant correlations of age with axial diffusivity, mean diffusivity, and fractional anisotropy (all, P < .001). There were also significant differences among cord regions for axial diffusivity, radial diffusivity, mean diffusivity, and fractional anisotropy (all, P < .001). CONCLUSIONS This research demonstrates that diffusion evolves in the pediatric spinal cord during development, dependent on both cord region and the diffusion index of interest. Future research could investigate how diffusion may be affected by common pediatric spinal pathologies.
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Affiliation(s)
- B B Reynolds
- Institute of Imaging Science (B.B.R., S.B., Q.R.W., A.A.W., A.T.N., H.R.F., B.R., S.A.S., A.B.), Vanderbilt University, Nashville, Tennessee
| | - S By
- Institute of Imaging Science (B.B.R., S.B., Q.R.W., A.A.W., A.T.N., H.R.F., B.R., S.A.S., A.B.), Vanderbilt University, Nashville, Tennessee
| | - Q R Weinberg
- Institute of Imaging Science (B.B.R., S.B., Q.R.W., A.A.W., A.T.N., H.R.F., B.R., S.A.S., A.B.), Vanderbilt University, Nashville, Tennessee
| | - A A Witt
- Institute of Imaging Science (B.B.R., S.B., Q.R.W., A.A.W., A.T.N., H.R.F., B.R., S.A.S., A.B.), Vanderbilt University, Nashville, Tennessee
| | - A T Newton
- From the Department of Radiology and Radiological Sciences (A.T.N., P.C., S.A.S., A.B.).,Pediatrics (A.T.N.).,Institute of Imaging Science (B.B.R., S.B., Q.R.W., A.A.W., A.T.N., H.R.F., B.R., S.A.S., A.B.), Vanderbilt University, Nashville, Tennessee
| | - H R Feiler
- Institute of Imaging Science (B.B.R., S.B., Q.R.W., A.A.W., A.T.N., H.R.F., B.R., S.A.S., A.B.), Vanderbilt University, Nashville, Tennessee
| | - B Ramkorun
- Institute of Imaging Science (B.B.R., S.B., Q.R.W., A.A.W., A.T.N., H.R.F., B.R., S.A.S., A.B.), Vanderbilt University, Nashville, Tennessee
| | | | - P Couture
- From the Department of Radiology and Radiological Sciences (A.T.N., P.C., S.A.S., A.B.)
| | - J E Martus
- Division of Pediatric Orthopaedics (J.E.M.), Monroe Carell Jr. Children's Hospital at Vanderbilt, Nashville, Tennessee
| | | | - J C Wellons
- From the Department of Radiology and Radiological Sciences (A.T.N., P.C., S.A.S., A.B.).,Department of Ophthalmology (S.A.S., J.C.W. III), Vanderbilt University Medical Center, Nashville, Tennessee
| | - S A Smith
- From the Department of Radiology and Radiological Sciences (A.T.N., P.C., S.A.S., A.B.).,Department of Biomedical Engineering (S.A.S.).,Institute of Imaging Science (B.B.R., S.B., Q.R.W., A.A.W., A.T.N., H.R.F., B.R., S.A.S., A.B.), Vanderbilt University, Nashville, Tennessee.,Department of Ophthalmology (S.A.S., J.C.W. III), Vanderbilt University Medical Center, Nashville, Tennessee
| | - A Bhatia
- From the Department of Radiology and Radiological Sciences (A.T.N., P.C., S.A.S., A.B.) .,Institute of Imaging Science (B.B.R., S.B., Q.R.W., A.A.W., A.T.N., H.R.F., B.R., S.A.S., A.B.), Vanderbilt University, Nashville, Tennessee
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Rozzelle CJ, Reed GT, Kirkman JL, Shannon CN, Chern JJ, Wellons JC, Tubbs RS. Sonographic determination of normal Conus Medullaris level and ascent in early infancy. Childs Nerv Syst 2014; 30:655-8. [PMID: 24178234 DOI: 10.1007/s00381-013-2310-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Accepted: 10/15/2013] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Controversial reports exist in the literature regarding both the spinal level of the conus medullaris (CM) in normal infants and the age at which the CM achieves its adult level. Autopsy studies have demonstrated ascent continuing into early infancy while more recent imaging study series' suggest the adult conus level is attained by the 40th postmenstrual week. METHODS The authors conducted a retrospective review of 1,273 screening lumbar ultrasound studies performed over 5 years at a pediatric tertiary referral center. All patients were infants referred for initial imaging to rule out the presence of a tethered spinal cord. Referral sources included urban academic, urban private practice, and rural private practice pediatricians. After excluding studies lacking sufficient documentation (n = 90) and those reported as abnormal (n = 106), 1,077 remained for review. The CM level and patient age in days were recorded from each study. Statistical analysis was performed using unpaired t testing and ANOVA for continuous variables; chi-square for categorical data. RESULTS The mean CM level for infants in group I (ages 0-30 days) was compared to those in groups II (31-60 days) and group III (61-100 days). Group I had a mean CM level of 0.125 and 0.2 vertebral segments lower than groups II and III (p = 0.0005 and <0.0001, respectively). ANOVA comparison of all three groups confirmed a rostral migratory trend (p < 0.001). The prevalence of CM level caudal to L2 in group I was 13 %, group II 11.4 %, and group III 4.7 %; also indicating a significant rostral trend (p = 0.004). CONCLUSIONS Rostral migration of CM level continues through the first few months of post-natal life, albeit of limited extent. Documentation of continued ascent in a neonate may obviate the need for magnetic resonance imaging.
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Affiliation(s)
- C J Rozzelle
- Division of Pediatric Neurosurgery, Children's Hospital of Alabama, 1600 7th Avenue South, JFL 400, Birmingham, AL, 35233, USA,
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Pineda JA, Aono M, Sheng H, Lynch J, Wellons JC, Laskowitz DT, Pearlstein RD, Bowler R, Crapo J, Warner DS. Extracellular superoxide dismutase overexpression improves behavioral outcome from closed head injury in the mouse. J Neurotrauma 2001; 18:625-34. [PMID: 11437085 DOI: 10.1089/089771501750291864] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Oxidative stress is known to play an important role in the response of brain to traumatic insults. We tested the hypothesis that increased extracellular superoxide dismutase (EC-SOD) expression can reduce injury in a mouse model of closed head injury. Neurologic, cognitive, and histologic outcomes were compared between transgenic mice exhibiting a fivefold increase in EC-SOD activity and wild-type littermate controls. Severe or moderate transcranial impact was induced in anesthetized and physiologically controlled animals. After severe impact, transgenic mice had better neurological outcome at 24 hr postinjury (p = 0.038). Brain water content was increased, but there was no difference between groups. Moderate impact resulted in predominantly mild neurologic deficits in both groups at both 24 hr and 14 days postinjury. Morris water maze performance, testing cognitive function at 14-17 days after trauma, was better in EC-SOD overexpressors (p = 0.018). No differences were observed between groups for histologic damage in hippocampal CA1 and CA3. We conclude that EC-SOD has a beneficial effect on behavioral outcome after both severe and moderate closed head injury in mice. Because EC-SOD is believed to be predominantly located in the extracellular space, these data implicate an adverse effect of extracellular superoxide anion on outcome from closed head injury.
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Affiliation(s)
- J A Pineda
- Division of Pediatric Critical Care, Duke University Medical Center, Durham, North Carolina, 27710, USA
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Nellgård B, Mackensen GB, Pineda J, Wellons JC, Pearlstein RD, Warner DS. Anesthetic effects on cerebral metabolic rate predict histologic outcome from near-complete forebrain ischemia in the rat. Anesthesiology 2000; 93:431-6. [PMID: 10910493 DOI: 10.1097/00000542-200008000-00022] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Although reduction of cerebral metabolic rate is thought to contribute to anesthetic neuroprotection, histologic evidence to support this concept has not been provided. In this study, histologic outcome was evaluated in rats subjected to different durations of severe forebrain ischemia while anesthetized with volatile anesthetics that have substantially different effects on cerebral metabolic rate. METHODS Normothermic rats that underwent fasting were anesthetized with 0.75 minimum alveolar concentration (MAC) isoflurane-60% nitrous oxide (N2O) or 0.75 MAC halothane-60% N2O. Ischemia was induced with use of a combination of bilateral carotid occlusion and controlled hypotension. Rats in the isoflurane group were subjected to 6.5 min or 8.0 min ischemia, whereas the halothane group received 6.5 min ischemia. Histologic damage was assessed 4 days later. RESULTS With 6.5 min ischemia, mean +/- SD, hippocampal CA1 percent of dead (% dead) neurons was reduced with isoflurane-N2O (45 +/- 18) versus halothane-N2O (60 +/- 23, P = 0. 023). Eight minutes of ischemia increased % dead neurons in the isoflurane-N2O group (60 +/- 17, P = 0.017). There was no difference between the isoflurane 8.0-min and halothane 6.5-min groups (P = 0. 935). A similar pattern was observed in hippocampal CA4 and the neocortex. Striatal damage was not affected by anesthetic or ischemic duration. CONCLUSIONS At 6.5 min ischemia, isoflurane provided improved outcome versus halothane. Previous research has shown that 0.75 MAC isoflurane-N2O increases the time to onset of ischemic depolarization by 1.5 min and reduces cerebral metabolic rate by 42% versus 0.75 MAC halothane-N2O. In the current study, when the duration of ischemia was increased by 1.5 min in the isoflurane-N2O group, histologic outcome became similar to that in halothane-N2O-anesthetized rats. These results provide evidence that cerebral metabolic rate reduction has an advantageous effect on outcome from severe brain ischemia, but also suggest that such benefit is likely to be small.
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Affiliation(s)
- B Nellgård
- Departments of Anesthesiology, Pediatrics, and Surgery, Duke University Medical Center, Durham, NC 27710, USA
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