Shalini Narayana1, Roozbeh Rezaie2, Samuel S McAfee3, Asim F Choudhri4, Abbas Babajani-Feremi2, Stephen Fulton5, Frederick A Boop6, James W Wheless5, Andrew C Papanicolaou7. 1. Division of Clinical Neurosciences, Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee; Le Bonheur Neuroscience Institute, Le Bonheur Children's Hospital, Memphis, Tennessee; Department of Neurobiology and Anatomy, University of Tennessee Health Science Center, Memphis, Tennessee. Electronic address: snaraya2@uthsc.edu. 2. Division of Clinical Neurosciences, Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee; Le Bonheur Neuroscience Institute, Le Bonheur Children's Hospital, Memphis, Tennessee. 3. Le Bonheur Neuroscience Institute, Le Bonheur Children's Hospital, Memphis, Tennessee. 4. Le Bonheur Neuroscience Institute, Le Bonheur Children's Hospital, Memphis, Tennessee; Department of Radiology, University of Tennessee Health Science Center, Memphis, Tennessee; Department of Neurosurgery, University of Tennessee Health Science Center, Memphis, Tennessee. 5. Le Bonheur Neuroscience Institute, Le Bonheur Children's Hospital, Memphis, Tennessee; Division of Pediatric Neurology, University of Tennessee Health Science Center, Memphis, Tennessee. 6. Le Bonheur Neuroscience Institute, Le Bonheur Children's Hospital, Memphis, Tennessee; Department of Neurosurgery, University of Tennessee Health Science Center, Memphis, Tennessee. 7. Division of Clinical Neurosciences, Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee; Le Bonheur Neuroscience Institute, Le Bonheur Children's Hospital, Memphis, Tennessee; Department of Neurobiology and Anatomy, University of Tennessee Health Science Center, Memphis, Tennessee.
Abstract
OBJECTIVE: Accurate noninvasive assessment of motor function using functional MRI (fMRI) and magnetoencephalography (MEG) is a challenge in patients who are very young or who are developmentally delayed. In such cases, passive mapping of the sensorimotor cortex is performed under sedation. We examined the feasibility of using transcranial magnetic stimulation (TMS) as a motor mapping tool in awake children younger than 3 years of age. METHODS: Six children underwent motor mapping with TMS while awake as well as passive sensorimotor mapping under conscious sedation with MEG during tactile stimulation (n = 5) and fMRI during passive hand movements (n = 4). RESULTS: Stimulation of the motor cortex via TMS successfully elicited evoked responses in contralateral hand muscles in 5 patients. The location of primary motor cortex in the precentral gyrus identified by TMS corresponded with the postcentral location of the primary sensory cortex identified by MEG in 2 patients and to the sensorimotor cortex identified by fMRI in 3 children. In this cohort, we demonstrate that TMS can illuminate abnormalities in motor physiology including motor reorganization. We also demonstrate the feasibility of using TMS-derived contralateral silent periods to approximate the location of motor cortex in the absence of an evoked response. When compared to chronological age, performance functioning level appears to be better in predicting successful mapping outcome with TMS. CONCLUSIONS: Our findings indicate that awake TMS is a safe alternative to MEG and fMRI performed under sedation to localize the motor cortex and provides additional insight into the underlying pathophysiology and motor plasticity in toddlers.
OBJECTIVE: Accurate noninvasive assessment of motor function using functional MRI (fMRI) and magnetoencephalography (MEG) is a challenge in patients who are very young or who are developmentally delayed. In such cases, passive mapping of the sensorimotor cortex is performed under sedation. We examined the feasibility of using transcranial magnetic stimulation (TMS) as a motor mapping tool in awake children younger than 3 years of age. METHODS: Six children underwent motor mapping with TMS while awake as well as passive sensorimotor mapping under conscious sedation with MEG during tactile stimulation (n = 5) and fMRI during passive hand movements (n = 4). RESULTS: Stimulation of the motor cortex via TMS successfully elicited evoked responses in contralateral hand muscles in 5 patients. The location of primary motor cortex in the precentral gyrus identified by TMS corresponded with the postcentral location of the primary sensory cortex identified by MEG in 2 patients and to the sensorimotor cortex identified by fMRI in 3 children. In this cohort, we demonstrate that TMS can illuminate abnormalities in motor physiology including motor reorganization. We also demonstrate the feasibility of using TMS-derived contralateral silent periods to approximate the location of motor cortex in the absence of an evoked response. When compared to chronological age, performance functioning level appears to be better in predicting successful mapping outcome with TMS. CONCLUSIONS: Our findings indicate that awake TMS is a safe alternative to MEG and fMRI performed under sedation to localize the motor cortex and provides additional insight into the underlying pathophysiology and motor plasticity in toddlers.
Authors: Jesse L Kowalski; Samuel T Nemanich; Tanjila Nawshin; Mo Chen; Colleen Peyton; Elizabeth Zorn; Marie Hickey; Raghavendra Rao; Michael Georgieff; Kyle Rudser; Bernadette T Gillick Journal: J Clin Med Date: 2019-08-13 Impact factor: 4.241
Authors: Shalini Narayana; Savannah K Gibbs; Stephen P Fulton; Amy Lee McGregor; Basanagoud Mudigoudar; Sarah E Weatherspoon; Frederick A Boop; James W Wheless Journal: Front Neurol Date: 2021-05-19 Impact factor: 4.003
Authors: Bernadette T Gillick; Andrew M Gordon; Tim Feyma; Linda E Krach; Jason Carmel; Tonya L Rich; Yannick Bleyenheuft; Kathleen Friel Journal: Front Pediatr Date: 2018-03-16 Impact factor: 3.418