hemangiomas are categorized as racemose , capillary , cavernous , and venous , according to the size of their vascular spaces . cavernous and venous hemangiomas have low blood flow , because they lack arterial or capillary components . histopathologically , venous hemangiomas contain dilated vessels with thick , fibrous walls , whereas cavernous hemangiomas have capillary - sized vessels lined by flat endothelial cells . we report the first case of a venous hemangioma of the pps and discuss its typical radiographic findings . a 49-year - old female patient was referred for evaluation of swelling in the right submandibular region . she had swelling for the first time 3 weeks earlier , and it had not improved after medical treatment . clinical examination revealed a soft mass in the right submandibular region and a bulge at the right lateral pharyngeal wall . a contrast - enhanced computed tomography ( ct ) scan revealed a cystic lesion , 4.63.0 cm , with contrast non - enhancement in the parapharyngeal space ( pps ) . mri showed a well - circumscribed non - enhancing mass with high signal intensity on t2-weighted images ( fig . the cystic lesion of the pps was surgically removed using a transcervical approach . during surgery the lesion bled profusely , but the mass was bluntly dissected from the surrounding structures . the surgical specimen , measuring 4.34.52 cm , showed a pale - to - dark brown soft cut surface with a blood - filled spongy vascular lesion . microscopic examination revealed blood - filled sinusoidal spaces with large irregular lumens and thick walls lined by endothelial cells ( fig . postoperative recovery was uneventful , and there has been no evidence of cranial nerve palsy or tumor recurrence after one year . pps has a complex anatomy and close proximity to vital anatomical structures , with which it may become involved by various pathological processes . presenting symptoms of pps tumors may be attributed to the size of the mass and compression of neighboring structures ( 1 ) . we had difficulty with the preoperative diagnosis , due to the absence of typical symptoms or signs of a vascular lesion in the pps , such as pulsation or bruit . fine - needle aspiration cytology ( fnac ) was also not helpful in reaching a diagnosis . although an exact tissue characterization of hemangioma in the pps could not be made on fnac , contrast - enhanced ct and magnetic resonance imaging ( mri ) should be included in differentiating these lesions from other tumors of the pps . in general , mr imaging is superior to ct imaging in its ability to ascertain the soft tissue characteristics of pps tumors ( 2 ) . changes in the blood flow dynamics within a hemangioma result in thrombus formation and phleboliths ( 3 ) . phleboliths are calcified nodules that can be regarded as a characteristic property of venous or cavernous hemangiomas . ct with contrast is an excellent imaging technique for revealing phleboliths . although mri is not sensitive for the detection of small amounts of calcification , large amounts of calcification show discrete low signal intensity on all pulse sequences mri can produce high signal intensities , representing the blood , as well as focal heterogeneities , representing areas of thrombosis , fibrosis , or calcification ( 4 ) . although mri is very useful for the detection of vascular lesions , the detectability of phleboliths on ct images is superior to that by mri . some reports have shown that plain x - ray films may also reveal calcified lesions . when imaging shows calcification in the pps , the differential diagnosis may include pleomorphic adenoma of the deep lobe of the parotid gland and metastatic thyroid carcinoma of the pps . pleomorphic adenoma with foci of chondroid or osteoid stroma can demonstrate opacities on imaging , but usually shows minute , scattered flecks . additionally , in cases of metastatic thyroid carcinoma of the pps , large flocculent calcification is seen on ct images ( 5 ) . venous hemangioma can not be clinically or radiologically differentiated from cavernous hemangioma , because of their similar characteristics . however , perfusion and blood pool scintigraphy has been demonstrated to have high sensitivity for detecting head and neck hemangioma , and can also differentiate between cavernous and venous hemangiomas ( 6 ) . they tend to be larger and less well circumscribed , and show no tendency to regress ( 7 ) . attention needs to be given to the tumor location , extent , growth rate , and accessibility as well as the patient 's age and esthetic concerns . the excision of large tumors in the pps can be challenging , given the risk for severe hemorrhage and nerve injury . a surgical approach should be chosen according to the tumor size and location , its relationship to the great vessels , and any suspicion of malignancy . generally , hemangiomas in the pps , including venous hemangioma , can be resected by using a transcervical approach . profuse bleeding often occurs during surgery , but after all of the pathology has been removed , the bleeding will cease . when surgery is impossible , the use of corticosteroids , cryotherapy , feeding vessel ligation , embolization , and fibrosing agents can be considered as alternatives ( 8) . in summary , we present the first reported case of venous hemangioma occurring in the parapharyngeal space . considering that a presumptive diagnosis of most pps tumors can be made based on imaging studies , preoperative imaging findings are very important in approaching these lesions . it may be that multiple , spotty , calcific nodules , 13 mm in size , within a cystic lesion on ct images indicate the pathognomonic finding of hemangioma in the pps .
a hemangioma of the parapharyngeal space ( pps ) is an extremely rare tumor and is responsible for 0.5 - 1% of all tumors occurring in the pps . 
 we report a case of pps venous hemangioma in a 49-year - old woman presenting with diffuse swelling in the submandibular region . a preoperative computed tomography ( ct ) scan showed a cystic mass with multiple calcifications in the pps . 
 the calcific nodules were round and about 2 mm in diameter . 
 the hemangioma was completely resected via a transcervical approach . during surgery 
 , we found several calcific nodules , which represented phleoboliths or areas of thrombosis with dystrophic calcification . despite its rarity , 
 a venous hemangioma of the pps should be considered in a differential diagnosis when a cystic mass with calcification is found by ct scan . to our knowledge , this is the first reported case of a pps venous hemangioma ; we describe its pathognomonic findings on imaging .