Clinical trial NCT06577649: Pain and Perceptual Distortion of Face
Official title: From Pain in the Face to Perceptual Distortion: Exploring Mechanisms and Novel Treatment Strategies
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Neuropathic Pain
Orofacial Pain
Keywords: Repetitive transcranial magnetic stimulation
N-of-1 trials
Perceptual distortion
Post-traumatic trigeminal neuropathic pain
Lead sponsor: University of Aarhus
Sponsor class: OTHER
First posted: 2024-08-29
Enrollment: 12
Sex: ALL
Minimum age (years): 18
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: "n-of-1" single-blinded randomized controlled cross-over design: (A) active-sham-active-sham or (B) sham-active-sham-active.
Primary purpose: TREATMENT

Brief summary: Post-traumatic trigeminal neuropathic pain (PTNP) is "a unilateral or bilateral facial or oral pain following and caused by trauma to the trigeminal nerve(s), with other symptoms and/or clinical signs of trigeminal nerve dysfunction, and persisting or recurring for more than 3 months". PTNP may result from a major craniofacial/oral trauma or may be subsequent to relatively minor dental treatments such as teeth extractions, surgeries, root canal treatment. Patients suffering from this condition have a significantly reduced quality of life. Unfortunately, the currently available management modalities are associated with limited success and side effects.

Repetitive transcranial magnetic stimulation (rTMS), which is a safe, non-invasive brain stimulation technique has emerged as a potential treatment for chronic pain. In this study, the purpose is to explore the potential of rTMS in treating the persistent neuropathic pain by providing individualized treatment for the sufferers.

Detailed description: In addition to pain, a curious observation in people with PTNP is that they report that the painful facial area is "swollen" or "feels differently". There are often no clinical signs or physical differences present, hence such self-reported "illusions" may represent a kind of disrupted body image or a "perceptual distortion" of the face and can be speculated to contribute to the maintenance of facial pain. rTMS paradigms are being widely applied in both therapeutic and investigative studies.In this project, the aim is to employ continuous theta-burst stimulation (cTBS), an inhibitory rTMS paradigm, to evaluate its effect on pain perception and PD in people with PTNP.

In this project, people with PTNP (N=9) received a rTMS (50 Hz, 600 pulses for 40s) session/week as intervention for four consecutive weeks at the primary somatosensory cortex (face area) in a "n-of-1" single-blinded randomized controlled cross-over design: (A) active-sham-active-sham or (B) sham-active-sham-active. That is the same participant received both active and sham either in the (A) order or (B). Pain intensity and perceptual distortion (PD) as perceived size changes of the affected face area were measured at baseline, immediately, 60 mins after rTMS in each session and end of the session (a week after rTMS), one and three months after rTMS. Questionnaires on quality of life, jaw function, sleep quality were also assessed. Changes in pain and PD after each intervention were evaluated.

Eligibility criteria: Inclusion Criteria:

* Persistent Post-traumatic trigeminal neuropathic pain patients for 6 months or longer
* Stable on analgesic medication

Exclusion Criteria:

* past history of TMS therapy or TMS-related contraindications (pacemaker, epilepsy etc.).
* Major stroke
* Pregnancy
* Severe organic brain damage

Primary outcomes:
measure: Changes in pain intensity
timeFrame: Prior to intervention at each session (baseline) to the end of that session (7 days after intervention).
measure: Changes in perceptual distortion
timeFrame: Prior to intervention at each session (baseline) to the end of that session (7 days after intervention).
Secondary outcomes:
measure: Changes in sleep quality
timeFrame: Prior to intervention at each session (baseline) to the end of that session (7 days after intervention), 1 and 3 months after intervention.
measure: Changes in perceived health or health related quality of life
timeFrame: Prior to intervention at each session (baseline) to the end of that session (7 days after intervention), 1 and 3 months after intervention.
measure: Changes in oral-health related quality of life
timeFrame: Prior to intervention at each session (baseline) to the end of that session (7 days after intervention), 1 and 3 months after intervention.
measure: Changes in functional limitation of the jaw.
timeFrame: Prior to intervention at each session (baseline) to the end of that session (7 days after intervention), 1 and 3 months after intervention.
measure: Changes in Psychological Distress
timeFrame: Prior to intervention at each session (baseline) to the end of that session (7 days after intervention), 1 and 3 months after intervention.
measure: Changes in Pain Catastrophizing
timeFrame: Prior to intervention at each session (baseline) to the end of that session (7 days after intervention), 1 and 3 months after intervention.
measure: Changes in patients health
timeFrame: Prior to intervention at each session (baseline) to the end of that session (7 days after intervention), 1 and 3 months after intervention.
measure: Changes in neuropathic pain characteristics
timeFrame: Prior to intervention at each session (baseline) to the end of that session (7 days after intervention), 1 and 3 months after intervention.
Other outcomes:
Locations:
city: Aarhus C
country: Denmark
facility: Department of Dentistry and Oral Health
Study officials:
affiliation: University of Aarhus
name: Simple F Kothari, BDS, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Kothari SF, Dagsdottir LK, Kothari M, Blicher JU, Kumar A, Buchholtz PE, Ashkanian M, Svensson P. Effect of repetitive transcranial magnetic stimulation on altered perception of One's own face. Brain Stimul. 2020 May-Jun;13(3):554-561. doi: 10.1016/j.brs.2020.01.001. Epub 2020 Jan 8.