Imaging Characteristics Of CT,MRI Of Tumors In The Parapharyngeal Space Of Skull Base And The Choice Of Surgical Approach

Objective To discuss imaging characteristics of CT,MRI of tumors in the parapharyngeal space of skull base,provide important basis to the security to different approaches.Method63 patients with tumor of para-pharynx and cranial base by pathological diagnosis in the first affiliated hospital of Anhui Medical University otolaryngology Head and Neck Surgery were analyzed retrospectively from 2002.1 to 2014.12.Observing the different imaging characteristics of CT,MRI,including the shape,size and nature of the tumor type,presence of coated,the relationship with the surrounding tissue and presence of metastasis,for analysising and discussion the choice of surgical approach.There were 56 cases of benign tumor,7 cases were malignant tumor.31 cases(49.2%)of neurogenic tumors,21 cases(33.3%)of pleomorphic adenoma,3 cases(4.8%)of carotid body tumor,1 case(1.6%)of chromaffin tumor,4 cases(6.3%)of nasopharyngeal carcinoma(NPC)near the base of skull pharynx clearance transfer,2cases(3.2%)of tonsil carcinoma and 1 case(1.6%)of parotid gland deep mucous epidermoid carcinoma.In this group of cases,neurogenic tumor and pleomorphic adenoma were located near the pharynx,all characterized by round or circular boundary clear,coated complete lump,part of pleomorphic adenoma are slightly lobulated,which are the areas of necrosis capsule by CT imaging.Because both have no marked in CT imaging,by observing carotid sheath compressive displacement of the relationship between the lesions and parotid gland deep lobe for differential diagnosis in CT or MRI imaging before operation.The carotid body tumor expression soft tissue mass,clear margin and morphological rules in CT imaging,and can be obviously strengthen enhancement scanning.The separation of external characteristic change is internal carotid artery,presenting the tall shape change,and the ample empty vascular imaging in T2W1 imaging,that is pepper salt.The 7 cases of malignant tumor expression characterized by the mass low signal intensity in CT imaging,Sometimes can see the multiple swollen lymph nodes,which can be integration,strengthen the scanning visible part,may be accompanied by necrosis.This group of 63 cases were surgery under general anesthesia,the surgical approachs were as follows.6 of 31 cases of neurogenic tumour used pure endoscopic resection;10 of 31 cases of schwannoma and 2 cases of carotid body tumor used the neck into the road,of which the 6 cases with nasal endoscopic approach;1 case vagus body tumor,1 case internal carotid artery,1case of huge tonsil carcinoma and 2 cases of pleomorphic adenoma resection with mandibular outer screwing in road.Other 22 cases used different treatments of mandible,including pulling mandible to fomer direction,hemisection of mandibular,mandibular ramus fracture and reset and partial resection of mandibular ramus.6 cases with maxillary swing including 4 cases of neurogenic tumors and 2cases with postradiation recurrent nasopharyngeal carcinoma.4 cases of clearance schwannoma infring the front skull base near the base of skull pharynx with orbital zygomatic approach.All cases all successful got through surgeries,according to the defect size and presence of bone in the base of skull pharynx using pectoralis major myocutaneous flap,mucosal flap,autologous bonnet fascial flap and chin lobe flap to repair.Post-operative hoar seness occurred in 3 cases;Horner syndrome occurred in 4cases;2 cases with postradiation recurrent nasopharyngeal carcinoma were effective in improving theinterincisor distance.10 patients draw ED trachea cannula after six months and breathed smoothly.33 cases of different teatments of mandible and maxilla had no obvious influence in eating disorde.The malignant tumor cases accepted comprehensive treatment after operation.Postoperative follow-up of 2 to 14 years,no recurrence of benign tumors,3 cases died of malignant tumor,including 1 case of tonsil adenoid cystic carcinoma and 2 cases of recurrent nasopharyngeal carcinoma.Conclusions The CT and MRI imaging can show the characteristics of various tumors near the base of skull pharynx clearance.If the source of tumor form,density,the advantages of the relationship with the surrounding tissue,the strengthening of the tumors after enhancement scanning and the inside situation of tumour are acquainted andused,which is of great significance to improve the gap near the base of skull pharynx tumor early diagnosis and differential diagnosis.It can help to the choice of appropriate surgical approach and the improvement of the operation efficiency and safety,reduce the surgical complications by preoperative effective use and evaluation.