title: Lateral pterygoid muscle volume and migraine in patients with temporomandibular disorders.
abstract: OBJECTIVE
  Lateral pterygoid muscle (LPM) plays an important role in jaw movement and has been implicated in Temporomandibular disorders (TMDs). Migraine has been described as a common symptom in patients with TMDs and may be related to muscle hyperactivity. This study aimed to compare LPM volume in individuals with and without migraine, using segmentation of the LPM in magnetic resonance (MR) imaging of the TMJ.
  
  
  METHODS
  Twenty patients with migraine and 20 volunteers without migraine underwent a clinical examination of the TMJ, according to the Research Diagnostic Criteria for TMDs. MR imaging was performed and the LPM was segmented using the ITK-SNAP 1.4.1 software, which calculates the volume of each segmented structure in voxels per cubic millimeter. The chi-squared test and the Fisher's exact test were used to relate the TMD variables obtained from the MR images and clinical examinations to the presence of migraine. Logistic binary regression was used to determine the importance of each factor for predicting the presence of a migraine headache.
  
  
  RESULTS
  Patients with TMDs and migraine tended to have hypertrophy of the LPM (58.7%). In addition, abnormal mandibular movements (61.2%) and disc displacement (70.0%) were found to be the most common signs in patients with TMDs and migraine.
  
  
  CONCLUSIONS
  In patients with TMDs and simultaneous migraine, the LPM tends to be hypertrophic. LPM segmentation on MR imaging may be an alternative method to study this muscle in such patients because the hypertrophic LPM is not always palpable.
authors: Department of Diagnosis and Surgery, São José dos Campos Dental School, UNESP, São Paulo, Brazil.
authors: Sérgio Lúcio Pereira de Castro
authors: SL
authors: Lopes
authors: Department of Pediatric Dentistry and Orthodontics, University of São Paulo City, UNICID, São Paulo, Brazil.
authors: André Luiz Ferreira
authors: AL
authors: Costa
authors: Department of Oral Diagnosis, School of Dentistry, UNICAMP, Piracicaba, São Paulo, Brazil.
authors: Thiago de Oliveira
authors: Tde O
authors: Gamba
authors: Department of Oral Diagnosis, School of Dentistry, UNICAMP, Piracicaba, São Paulo, Brazil.
authors: Isadora Luana
authors: IL
authors: Flores
authors: Department of Specific Formation, Area of Radiology, Nova Friburgo Dental School, Fluminense Federal University, Nova Friburgo, Rio de Janeiro, Brazil.
authors: Adriana Dibo
authors: AD
authors: Cruz
authors: Laboratory of Neuroimaging, Department of Neurology, Faculty of Medical Sciences, UNICAMP, Campinas, São Paulo, Brazil.
authors: Li Li
authors: LL
authors: Min
keywords: Magnetic Resonance Imaging; Migraine Disorders; Pterygoid Muscles; Temporomandibular Joint Disorders