Imaging Of Parapharyngeal Space Tumors And Selection Of Treatment

Objective:To analyze the clinical data of 75 cases of parapharyngeal space tumors,including CT and MRI,predict the pathological nature of the tumor,evaluate the relationship of the tumor to carotid sheath,parotid gland,skull base,and hard palate,and guide the treatment based on the imaging characteristics of the tumor.Methods:A retrospective analysis of 75 cases' clinical data,including CT and MRI,of parapharyngeal space tumor admitted to Department of Otorhinolaryngology,First Affiliated Hospital of Chongqing Medical University from June 2012 to September 2019 was carried out,and tumors which closely related to blood vessels and vascular tumors were examined by CTA or MRA,and for those closely related to peripheral nerves,MRN examination was performed.The pathological nature of the tumor was predicted,the relationship of the tumor to carotid sheath,parotid gland,skull base and hard palate was evaluated,and the treatment was selected according to the imaging characteristics of the tumor.Intraoperative blood loss,operation time,postoperative complications,postoperative recovery time,etc.were counted,and the survival of patients was followed up.Results:Imaging revealed 69 benign tumors and 6 malignant tumors,among them,8 benign tumors chose to follow up,61 benign tumors and 6malignant tumors underwent surgery.17 cases of tumors which were located in the medial of carotid sheath,with the main body protruding toward the oropharynx,below the level of the hard palate,and more than5 mm away from the skull base,were operated by the transoral approach assisted by endoscope.31 cases with the tumor protruded toward the neck(15 cases were lateral of the carotid sheath,and 16 cases were medial)were resected by the transcervical approach.16 cases with the tumor harbored a broad interconnecting margin with the parotid gland were resected by the transparotid approach.There were 3 cases of other approaches(1 case of transnasal approach,1 case of combined transnasal and transcervical approach,and 1 case of combined transauricular-cervical approach).Postoperative complications occurred in 25 patients,including 9 cases of facial paralysis(6 cases of grade II,2 cases of grade III,1 case of grade IV),and 1 case of complete recovery;5 cases of Hornor's syndrome,1case recovered;tongue extension deflection in 3 cases and recovery in 2cases;tracheotomy was performed in 1 case because of postoperative oropharyngeal swelling;acute cerebral infarction was caused by thrombusdetachment in 1 case.Conclusion :1?Imaging results are important basis for the treatment of parapharyngeal space tumors.The choice of surgical approach should be based on imaging,including the relationship of tumors to great vessels of the neck,parotid gland,hard palate,and distance from skull base,combined with the pathological nature of the tumor.2?As regard to the imaging diagnosis difficulties of benign and malignant tumors,when the tumor subject is convex to the neck or nasopharynx,except for vascular or blood-rich tumors,puncture cytology or transnasopharyngeal biopsy can help further treatment.3?The indications for the transoral approach are: 1)tumor protruding toward oropharynx;2)the main body(> 1/2)is below the hard palate plane;3)medial of the carotid sheath;4)distance from skull base ?5mm;5)independent or with narrow pedicle attachment of parotid gland.4?As regard to tumors protruding toward the neck,or with difficulty in transoral resection,transcervical approach should be performed.The transcervical approach should also be selected with the preoperative consideration of vascular tumors and paragangliomas.5?For tumors harbored a broad interconnecting margin of parotid gland,transparotid approach should be selected.