BACKGROUND:Because the artery leading to the glossopharyngeal nerve is small and complex,insufficient blood supply can occur due to atherosclerosis,occlusion,or injury.This sometimes results in corresponding newe degeneration,demyelination,and/or arachnoid adhesion.OBJECTIVE:To observe the nutrient artery origin of the glossopharyngeal nerve root in the medulla oblongata region,as well as the relationship between the artery and glossopharyngeal nerve root,to verify dependence of primary glossopharyngeal neuralgia,which is related to contact and compression of the nutrient artery of the glossopharyngeal nerve root.DESIGN,TIME AND SETTING:Repetitive measurement.The experiment was performed at Harbin Medical University and Daqing Oilfields General Hospital between November 2006 and April 2007.MATERIALS:Ten cadaver heads(seven male and three female)were supplied bv the Department of Anatomy,Harbin Medical University.A total of 15 patients(nine male and six female),aged 38-56,that suffered from glossopharyngeal neuralgia were treated at Daqing Oilfields General Hospital and were between 38-56 years old.All cadaver heads were strictly handled according to the Guideline for Medical Ethics Committee.The patients agreed to the criteria set for the study objects.METHODS:(1)The bilateral veins of the nutrient artery were dissected under a surgery microscope.A sliding caliper was used to measure the length of the glossopharyngeal nerve from the oblongata to the iugular foramen.The origin of the nutrient artery was noted.as well as the courser and diameter to explore the relationship between the glossopharyngeal nerve root and the vertebral artery.posterior inferior cerebellar artery,anterior inferior cerebellar artery,as well as the branching veins.(2)A total of 15 patients received glossopharyngeal neuralgia surgery.Contact or oppression of the glossopharyngeal nerve with the posterior inferior cerebellar artery,the anterior inferior cerebellar artery,vertebral artery,and its branches,were evaluated.MAIN OUTCOME MEASURES:The relationship and compression of the glossopharyngeal nerve with the posterior inferior cerebellar artery,anterior inferior cerebellar artery,vertebral armry,and its branches in cadaver sections and the living human body.RESULTS:(1)Cadaver dissection:the nutrient arteries of the glossopharyngeal nerve root originated from three or two branches of the posterior iriferior cerebellar artery,anterior inferior cerebellar artery,and dorsolateral medullary artery.During the procedure.four sides of the glossopharyngeal nerve root received contact or compression from the posterior inferior cerebellar artery trunk or thick loop branch.The four sides represented 20% of the area,and the two sides that received glossopharyngeal nerve root contact or compression from the anterior inferior cerebellar artery represented up to 10%.(2)Human living body:during surgery,obvious contact or compression of the glossopharyngeal nerve with three or more branches of the nutrient arteries accounted for 53.3% of the area.CONCLUSION:The cause of a number of primary glossopharyngeal neuralgia is related to contact and pressure of the nutrient artery of the glossopharyngeal nerve root.