Analysis Of Clinical Diagnosis And Surgical Treatment Of Tumors Involving The Pterygopalatine Fossa

Background:The position of pterygopalatine fossa is deep.Although small in size,its anatomical structure is complex;there are natural foramina and canals pertinent to the nasal cavity,nasopharynx,oral cavity,orbit,infratemporal fossa and middle cranial fossa,which makes it to be an important place of the rhino-orbital and rhino-cranial related surgery.Lesions involving the pterygopalatine fossa are common in tumors.Benign tumors are common in neurogenic tumors and juvenile nasopharyngeal angiofibromas;malignant ones include squamous-cell carcinoma,adenoid cystic carcinoma,lymphoma,sarcoma,malignant melanomaomma and myoepithelial carcinoma,et.The clinical manifestations varies with the main location and the invading structure of the tumor.The therapeutic regimen of benign tumors are radical surgery,which are similar to the malignant ones excepting the portions are sensitive to radiotherapy and chemotherapy.Because of its complex structures and its location close to the internal carotid artery and the bottom of the middle cranial fossa,we should accurate diagnosis and choose an effective surgical approach to remove the hole neoplasm as well as to reduce the complications,especially to avoid injury of large arteries and cranial nerves,which is the research path many experts search for.Objectives:To provide some practical experience for diagnosis and treatment of lesions in the pterygopalatine fossa by analysing the clinical manifestation,imaging data,surgical approach,surgical experience and prognosis.Methods:A retrospective study of 30 cases of tumors involving the pterygopalatine fossa.To analysis the clinical manifestations of all patients,the clinical symptoms of 12 patients were relatively simple,while the others were diverse.Consider with their imaging examination,11 cases were considered as benign tumors,while the others were malignant ones.All the 30 patients underwent CT scan,16 ones underwent MRI scan before operation(3 cases were examined with CTA and 6 cases with DSA).14 patients were treated with nasal endoscopic surgery,while the others were treated with extranasal approach surgery.The postoperative complications and prognosis were observed by nasal endoscopy or imaging scan and telephone follow-up.Results:The operation was successful in 30 patients with no serious complications occurred.The tumor were completely removed of 11 benign patients and 18 malignant patients,except 1 melanoma.There were 11 cases of benign tumor and 19 cases of malignant tumor confirmed by histopathological examination after operation.Including 5 schwannoma,6 angiofibroma,8 squamous cell carcinoma,3 adenoid cystic carcinoma,2 epithelial-myoepithelial carcinoma,1 myoepithelial carcinoma,1 leiomyosarcoma,1 chondroma sarcomatosum and 3 melanoma.11 benign cases,numbness in the maxillofacial region 2 cases-recovery 1 case half year after operation.As for 19 malignant cases,death 6 cases(2SCC,lACC,3MM),secondary operation 1 cases(SCC).Conclusions:1?Tumors involving several adjacent structures are commonly seen in pterygopalatine fossa.Early manifestation of benign tumors involving the pterygopalatine fossa lack of typical clinical features.The maxillary nerve dysfunction can remind us the PPF was probably invaded by malignant tumor.2?CT and MRI are the main methods for the diagnosis of the tumor involving the PPF.CTA can show the relationship between intracranial vessels and tumor.DSA and superselective arterial embolization can effectively diagnose fibroangioma and reduce the blood supply of the tumor.3?The operative approach with the shortest path to the tumor and less damage to the functional structure was chosen,according to the imaging examination before operation.The tansnasal approach can effectively remove the primary tumors mainly located near the midline of the skull base with the advantages of less injury,no facial scar formation and quick recovery.Maxillary resection approach can effectively remove tumors of maxillary sinus involving PPF and ITF.Lateral cervical approach,submandibular approach and split mandibular approach are mainly suitable for tumors close to the body surface,away from the midline of the skull base.The application of imaging navigator,multidisciplinary cooperation and precise operation can effectively remove giant benign tumors of PPF and prevent serious complications.For malignant tumors,the destruction of functional structures sometimes cannot be avoid,while it is necessary to removed to prevent tumor from recurrence.However,when it comes to the fatal complications,radical resection of tumor sometimes may not be completed,which need us combine the radical surgery with radiotherapy or chemotherapy.