title: Types of sublingual gland herniation observed during sonography of plunging ranulas.
abstract: OBJECTIVE
  Plunging ranulas have been shown to have a common trio of mylohyoid defects, sublingual gland herniation, and submandibular space fluid collections. The herniated sublingual gland may be susceptible to subclinical trauma. The purpose of this study was to investigate the frequency of occurrence of various types of active sublingual gland herniation observed during diagnostic sonographic studies.
  
  
  METHODS
  Sonographic findings of sublingual gland herniation from 76 patients with a total of 80 plunging ranulas are presented. All sublingual gland herniations, including those on the contralateral side, were documented at the time of the examinations and reviewed later. The sonographic appearances of active sublingual gland herniation were given the names "slide," "wobble," "mushroom," and "retrusion" to reflect the observed movement.
  
  
  RESULTS
  Mylohyoid defects were found in 98% of plunging ranulas. The different types of sublingual gland herniation observed were as follows: slide in 77.8%, wobble in 11.1%, mushroom in 9.7%, and retrusion in 1.4%. The unaffected contralateral side showed a wobble in 44.8% of cases and slide in 8.9%.
  
  
  CONCLUSIONS
  Sublingual gland herniation through mylohyoid defects is easily missed if one is unaware. Prior knowledge of the various types of sublingual gland herniation and their frequencies of occurrence are very helpful during diagnostic sonographic examinations.
authors: Department of Radiology, Middlemore Hospital, Manukau, New Zealand (P.J.); and Department of Surgery, University of Auckland, Auckland, New Zealand (R.J.). pjain@middlemore.co.nz.
authors: Prabha
authors: P
authors: Jain
authors: Department of Radiology, Middlemore Hospital, Manukau, New Zealand (P.J.); and Department of Surgery, University of Auckland, Auckland, New Zealand (R.J.).
authors: Ravi
authors: R
authors: Jain
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D003937:Diagnosis, Differential; D005260:Female; D006547:Hernia / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011900:Ranula / Q000000981:diagnostic imaging*; D013361:Sublingual Gland / Q000000981:diagnostic imaging*; D014463:Ultrasonography; D055815:Young Adult
keywords: head and neck ultrasound; mylohyoid defects; plunging ranulas; salivary glands; sublingual gland; submandibular space