PMID- 34072379
OWN - NLM
STAT- MEDLINE
DCOM- 20210705
LR  - 20210714
IS  - 2072-6651 (Electronic)
IS  - 2072-6651 (Linking)
VI  - 13
IP  - 6
DP  - 2021 May 29
TI  - Clinical and Neurophysiological Effects of Botulinum Neurotoxin Type A in Chronic 
      Migraine.
LID - 10.3390/toxins13060392 [doi]
LID - 392
AB  - Chronic pain syndromes present a subversion of both functional and structural 
      nociceptive networks. We used transcranial magnetic stimulation (TMS) to evaluate 
      changes in cortical excitability and plasticity in patients with chronic migraine 
      (CM) treated with botulinum neurotoxin type A (BoNT/A). We enrolled 11 patients 
      with episodic migraine (EM) and 11 affected by CM. Baseline characteristics for 
      both groups were recorded using single- and paired-pulse TMS protocols. The same 
      TMS protocol was repeated in CM patients after four cycles of BoNT/A completed in 
      one year. At baseline, compared with EM patients, patients with CM had a lower 
      threshold in both hemispheres (right hemisphere: 46% +/- 7.8 vs. 52% +/- 4.28, p = 
      0.03; left hemisphere: 52% +/- 4.28 vs. 53.54% +/- 6.58, p = 0.02). In EM, 
      paired-pulse stimulation elicited a physiologically shaped response, whereas in 
      CM, physiological intracortical inhibition (ICI) between 1 and 3 ms intervals was 
      absent at baseline. On the contrary, increasing intracortical facilitation (ICF) 
      was observed for all interstimulus intervals (ISIs). In CM, cortical excitability 
      was partially reduced after BoNT/A treatment, along with a significant decrease 
      observed in MIDAS score (from 20.7 to 9.8; p = 0.008). The lower motor threshold 
      in CM reflects a higher cortical hyperexcitability. The lack of physiological ICI 
      in CM could indicate sensitisation of the trigeminovascular system. Although 
      reduced, this type of response is still observable after treatment, despite a 
      marked clinical improvement. Our study suggests a long-term alteration of 
      cortical plasticity due to chronic pain.
FAU - Valente, Mariarosaria
AU  - Valente M
AD  - Clinical Neurology Unit, Santa Maria della Misericordia University Hospital, 
      33100 Udine, Italy.
AD  - Department of Medicine, University of Udine, 33100 Udine, Italy.
FAU - Lettieri, Christian
AU  - Lettieri C
AUID- ORCID: 0000-0002-8140-6277
AD  - Clinical Neurology Unit, Santa Maria della Misericordia University Hospital, 
      33100 Udine, Italy.
FAU - Russo, Valentina
AU  - Russo V
AD  - Clinical Neurology Unit, Santa Maria della Misericordia University Hospital, 
      33100 Udine, Italy.
AD  - Intensive Rehabilitation Unit, Santa Maria della Misericordia University 
      Hospital, 33100 Udine, Italy.
FAU - Janes, Francesco
AU  - Janes F
AUID- ORCID: 0000-0003-1534-1409
AD  - Clinical Neurology Unit, Santa Maria della Misericordia University Hospital, 
      33100 Udine, Italy.
FAU - Gigli, Gian Luigi
AU  - Gigli GL
AD  - Clinical Neurology Unit, Santa Maria della Misericordia University Hospital, 
      33100 Udine, Italy.
AD  - Department of Medicine, University of Udine, 33100 Udine, Italy.
LA  - eng
PT  - Journal Article
DEP - 20210529
PL  - Switzerland
TA  - Toxins (Basel)
JT  - Toxins
JID - 101530765
RN  - EC 3.4.24.69 (Botulinum Toxins, Type A)
SB  - IM
MH  - Adult
MH  - Botulinum Toxins, Type A/pharmacology/*therapeutic use
MH  - Chronic Disease
MH  - Female
MH  - Humans
MH  - Male
MH  - Migraine Disorders/physiopathology/*therapy
MH  - Motor Cortex/physiopathology
MH  - Transcranial Magnetic Stimulation/*methods
PMC - PMC8229748
OTO - NOTNLM
OT  - chronic headache
OT  - chronic pain
OT  - migraine
OT  - transcranial magnetic stimulation
COIS- The authors declare no conflict of interest.
EDAT- 2021/06/03 06:00
MHDA- 2021/07/06 06:00
PMCR- 2021/05/29
CRDT- 2021/06/02 01:35
PHST- 2021/04/30 00:00 [received]
PHST- 2021/05/20 00:00 [revised]
PHST- 2021/05/24 00:00 [accepted]
PHST- 2021/06/02 01:35 [entrez]
PHST- 2021/06/03 06:00 [pubmed]
PHST- 2021/07/06 06:00 [medline]
PHST- 2021/05/29 00:00 [pmc-release]
AID - toxins13060392 [pii]
AID - toxins-13-00392 [pii]
AID - 10.3390/toxins13060392 [doi]
PST - epublish
SO  - Toxins (Basel). 2021 May 29;13(6):392. doi: 10.3390/toxins13060392.