Development and Validation of a Disease-Specific Oromandibular Dystonia Rating Scale (OMDRS)

Abstract

Background: Oromandibular dystonia manifests with sustained or task-specific contractions of the masticatory, tongue, and/or other muscles in the stomatognathic system. Since its symptoms can vary, it has been difficult to objectively measure disease severity and post-treatment changes. Objective: To develop and validate a comprehensive measurement tool for oromandibular dystonia. Methods: An examiner-rated scale included three subscales for severity, disability, and pain, modified specifically for oromandibular dystonia from the Toronto Western Spasmodic Torticollis Rating Scale-2. To evaluate the severity of each subtype of oromandibular dystonia, four of the six items were selected according to the subtype (jaw closing dystonia, tongue dystonia, jaw opening dystonia, jaw deviation [protrusion] dystonia, and lip dystonia). A patient-administered questionnaire based on clinical features and other relevant aspects associated with oromandibular dystonia was developed, which included five subscales: general, eating, speech, cosmetic, and social/family life. The questionnaire, examiner-rated scale, and four subscales (sleep, annoyance, mood, and psychosocial functioning) of the Cervical Dystonia Impact Profile-58 were combined to construct the oromandibular dystonia rating scale (OMDRS). The reliability and validity of the scale were assessed using clinimetric testing. Results: Six hundred and eighteen patients with oromandibular dystonia (394 women and 224 men; mean age, 51.7 years) were evaluated by the OMDRS. The overall OMDRS showed high-level internal consistency measured by Cronbach's alpha (0.95) with a logical factor structure. Cronbach's alpha for the subscales was satisfactory to excellent, ranging from 0.72 to 0.94. All items revealed acceptable inter-rater reliability (kappa > 0.4, interclass correlation coefficient > 0.6). Repeated ratings of videotapes revealed acceptable intra-rater reliability for all items (kappa > 0.76, interclass correlation coefficient > 0.86). Test-retest reliability showed a significant (p < 0.001) correlation efficiency. The OMDRS showed significant (p < 0.001) convergent and discriminant validity and significant (p < 0.001) sensitivity to changes after botulinum toxin therapy. Conclusion: The OMDRS can be useful for the comprehensive evaluation of disease severity, disability, psychosocial functioning, and impact on the quality of life as well as therapeutic changes in patients with oromandibular dystonia.

Blepharospasm, Oromandibular Dystonia, and Meige Syndrome: Clinical and Genetic Update

“…The study compared the “movement-related cortical potentials” (MRCPs) between 6 OMD patients and 8 normal subjects and found that MRCP amplitudes over central and parietal areas for mouth opening and lateral movements were significantly reduced compared to normal subjects, which implies that impaired cortical preparatory process for jaw movements exist in OMD ( 61 ). Although scientists attempted to elucidate the pathophysiology of OMD using several neuroimaging techniques, its etiology remains unclear ( 61 , 62 ). Further research is needed to explore the pathophysiology of OMD to develop better treatments.…”

“…A case report found c.613T>A (p.F205I) mutation in OMD and this mutation produces frequent inclusions when expressed in cultured cells, a phenotype shared by the Δ E mutant TOR1A, but not wildtype protein ( 68 ). A case-control study found a significant association between rs1182 of TOR1A and BSP ( 62 ). While another study suggested that rs2296793, rs1182, and MtDEL of TOR1A were not associated with BSP ( 42 ).…”

Behandlungsstrategien bei oromandibulärer Dystonie

“…Drittens gibt es wenige Bewertungsskalen, um den Schweregrad der OMD und die Veränderungen nach der Behandlung zu beurteilen. Kürzlich wurde eine Bewertungsskala für OMD (oromandibular dystonia rating scale, OMDRS) entwickelt und validiert [101]. Daher ist es wichtig, mehr Patienten mit OMD richtig zu diagnostizieren, zu behandeln und klinische Studien mit einem hohen Evidenzniveau durchzuführen.…”

Effects of Botulinum Toxin Type A on Pain among Trigeminal Neuralgia, Myofascial Temporomandibular Disorders, and Oromandibular Dystonia

“…OMD is a focal type of dystonia involving the masticatory and/or lingual muscles. OMD includes jaw closing dystonia, jaw opening dystonia, lingual dystonia, jaw deviation dystonia, jaw protrusion dystonia, and lip dystonia [37,38]. A recent study postulated that OMD has an equal or higher prevalence of cervical dystonia or blepharospasm [62].…”

“…A recent study postulated that OMD has an equal or higher prevalence of cervical dystonia or blepharospasm [62]. The approaches to OMD treatment should be taken seriously not only by neurologists or neurosurgeons, but also by oral and maxillofacial surgeons or dentists [37][38][39]62]. Patients with OMD were successfully treated with BoNT/A.…”