Improved diagnosis of spinal cord disorders with contact heat evoked potentials

Abstract

Assessment of spinothalamic pathways with CHEPs is reliable and revealed the highest sensitivity in all SCDs. Specifically in incomplete lesions that spare dorsal pathways, CHEPs are sensitive to complement the clinical diagnosis.

Preserved Sensory-Motor Function Despite Large-Scale Morphological Alterations in a Series of Patients with Holocord Syringomyelia

“…This is in contrast to findings in traumatic incomplete SCI where lesions of the cervical cord (including central cord syndrome with circumscribed lesions of the central gray matter) show altered neurophysiological recordings and lead to obvious motor impairments of the upper limbs. 22,[29][30][31] However, sensory assessments (clinical and electrophysiological) provided a higher sensitivity to disclose the vulnerability of specific fiber tracts. 32 Segmental sensory function assessed by dSSEPs (to examine dorsal column-medial lemniscal pathway integrity) and by dCHEPs (to show lateral spinothalamic-tract function propagating information on pain and temperature) was significantly affected, 33,34 revealing considerable impairments in dCHEPs while dSSEPs were normal in half of the patients.…”

“…To exclude peripheral nerve damage, NCS, including F-wave recordings of the ulnar nerve (median nerve in Patient 35), were performed and compared with standard values. Sensory pathways (i.e., dorsal columns and spinothalamic tract) were assessed by testing light touch (LT) and pinprick (PP) sensation and by more detailed and sensitive recordings of dSSEPs and dCHEPs, 21,22 respectively, elicited in dermatomes C4, C6, and C8. All evoked potentials (EPs) were evaluated by means of amplitude and latency, compared with standard values, and rated as abolished (no EP response), impaired (reliable response but pathological findings of latency and/or amplitude), or normal response.…”

High sensitivity of contact-heat evoked potentials in “snake-eye” appearance myelopathy

“…Patients with concomitant neurological diseases, including radiculopathy, were excluded. 27 of the patients presented were included as part of a subgroup analysis in a previous study by the authors (Ulrich et al, 2013).…”

“…Although not yet established for routine clinical use, dermatomal contact-heat evoked potentials (dCHEPs) have emerged as a new technique to assess the functional integrity of pain pathways in spinal cord disorders (Wydenkeller et al, 2008;Haefeli and Curt, 2012;Kramer et al, 2012a,b,c;Ulrich et al, 2013). Noxious contact heat activates thinly myelinated A-delta fibres which project to dorsal horn interneurons before crossing the central grey and ascending in the contralateral spinothalamic tract (Chen et al, 2001(Chen et al, , 2006Valeriani et al, 2002;Granovsky et al, 2005Granovsky et al, , 2008Iannetti et al, 2006;Wall et al, 1999 Pain).…”

Journal Club: Improved diagnosis of spinal cord disorders with contact heat evoked potentials

“…4 Recent guidelines including the recommendations from the European Federation of Neurological Sciences, however, recommend LEP but could not identify studies that demonstrate the diagnostic value of CHEP. 6 HYPOTHESIS AND DESIGN The primary aim stated by Ulrich et al 7 was to assess the diagnostic value of CHEP in SCD. The authors investigated the sensitivity of CHEP compared with the current gold standard techniques (dSSEP, light touch [LT], and pinprick [PP]) to individuate specific ascending pathways involved in focal disorders of the spinal cord.…”