Postmortem investigation of mylohyoid hiatus and hernia: aetiological factors of plunging ranula.
The mylohyoid hiatus and hernia were discovered in the nineteenth century and were considered to explain the origin of the plunging ranula from the sublingual gland. This formed the rationale for sublingual sialadenectomy for the treatment of plunging ranula. However, a more recent, extensive histological investigation reported that hernias contained submandibular gland, which supported an origin of the plunging ranula from the submandibular gland and submandibular sialadenectomy for the treatment of plunging ranula. We therefore decided to investigate the occurrence and location of the hiatus and the histological nature of the hernia. Twenty-three adult cadavers were dissected in the submandibular region. The locations and dimensions of mylohyoid hiatuses were measured before taking biopsies of hernias. Hiatuses with associated hernias were found in ten cadavers: unilateral in six; and bilateral in four, in one of which there were three hiatuses. Sublingual gland was identified in nine hernias and fat without gland in six. This investigation supports clinical and experimental evidence that the plunging ranula originates from the sublingual gland and may enter the neck through the mylohyoid muscle. It confirms the rationale of sublingual sialadenectomy for the treatment of plunging ranula.
Department of Oral Pathology, King's College London Dental Institute at Guy's, King's College and St Thomas' Hospitals, London, England. john.harrison@kcl.ac.uk
John D
JD
Harrison
Ann
A
Kim
Saad
S
Al-Ali
Randall P
RP
Morton
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001344:Autopsy; D001706:Biopsy; D002102:Cadaver; D005260:Female; D006547:Hernia / Q000150:complications* / Q000473:pathology; D006801:Humans; D008297:Male; D008334:Mandible / Q000473:pathology* / Q000601:surgery; D008875:Middle Aged; D009334:Neck Muscles / Q000473:pathology / Q000601:surgery; D011900:Ranula / Q000209:etiology* / Q000473:pathology / Q000601:surgery; D012466:Salivary Gland Diseases / Q000150:complications* / Q000473:pathology / Q000601:surgery; D013361:Sublingual Gland / Q000473:pathology* / Q000601:surgery; D013363:Submandibular Gland / Q000473:pathology / Q000601:surgery
mylohyoid muscle; ranula; salivary gland disease; sublingual gland; submandibular gland