From Pain in the Face to Perceptual Distortion: Exploring Mechanisms and Novel Treatment Strategies
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- University of Aarhus
- Enrollment
- 12
- Locations
- 2
- Primary Endpoint
- Changes in pain intensity
Study Overview
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.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Crossover
- Primary Purpose
- Treatment
- Masking
- Single (Participant)
Masking Description
The order of interventions (A) active-sham-active-sham or (B) sham-active-sham-active were randomized using a computer-based random sequence generation program. The allocation was conducted by a nurse not involved in the project and consisted of 12 sealed, opaque and numbered envelopes consisting of information about the treatment order.
Eligibility Criteria
- Ages
- 18 Years to 75 Years (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
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
Outcomes
Primary Outcomes
Changes in pain intensity
Time Frame: Prior to intervention at each session (baseline) to the end of that session (7 days after intervention).
Changes in pain intensity from baseline to end of each session measured using self-reported pain dairy using a 0-10 visual analog scale (VAS; 0=no pain and 10=worst pain imaginable). The intervention (active and sham rTMS) were each given in 2 sessions. In total, the participant received 4 sessions of intervention.
Changes in perceptual distortion
Time Frame: Prior to intervention at each session (baseline) to the end of that session (7 days after intervention).
Perceptual distortion defined as perceived change in the size/shape of the affected face area will be measured using Numerical Rating Scale ranging from -100% through 0% to +100%, where 0% = no size change, -100% = half the size and +100% = double the size in comparison with non-affected side of face and drawings of the affected area. The changes will be measured from baseline to the end of each session as done for pain intensity.
Secondary Outcomes
- Changes in sleep quality(Prior to intervention at each session (baseline) to the end of that session (7 days after intervention), 1 and 3 months after intervention.)
- Changes in perceived health or health related quality of life(Prior to intervention at each session (baseline) to the end of that session (7 days after intervention), 1 and 3 months after intervention.)
- Changes in oral-health related quality of life(Prior to intervention at each session (baseline) to the end of that session (7 days after intervention), 1 and 3 months after intervention.)
- Changes in functional limitation of the jaw.(Prior to intervention at each session (baseline) to the end of that session (7 days after intervention), 1 and 3 months after intervention.)
- Changes in Psychological Distress(Prior to intervention at each session (baseline) to the end of that session (7 days after intervention), 1 and 3 months after intervention.)
- Changes in Pain Catastrophizing(Prior to intervention at each session (baseline) to the end of that session (7 days after intervention), 1 and 3 months after intervention.)
- Changes in patients health(Prior to intervention at each session (baseline) to the end of that session (7 days after intervention), 1 and 3 months after intervention.)
- Changes in neuropathic pain characteristics(Prior to intervention at each session (baseline) to the end of that session (7 days after intervention), 1 and 3 months after intervention.)