The CT findings of ossification in sinonasal inverted papilloma and its comparison with the originating site determined during surgery / 中华放射学杂志

ABSTRACT

Objective:To evaluate the CT characteristics of ossifying foci in sinonasal inverted papilloma (IP) and to compare with the tumor root shown intraoperatively.Methods:The clinical and CT imaging data of 127 patients with IP, which were proved by histopathology, were reviewed retrospectively from Beijing Tongren Hospital, Capital Medical University, during the period from January 2012 to December 2018. The number, location, shape, density of ossifying foci in sinonasal IP and the relationship with the wall of sinus were observed. The sites of ossification on CT scans were compared with the root of the tumors described in the corresponding patient′s operative records.Results:In 127 IP patients, 51 (40.2%) patients showed the ossification in the tumor on CT. Single ossifying foci were found in 35 cases and multiple in 16 cases. The ossification affected single site of the sinonasal tract ( n=16) or distributed diffusely ( n=35). In the 50 cases, the ossifying foci extended along the long axis of the affected sinus appearing as branched ( n=19), striped ( n=16), linear ( n=7), lumpy ( n=2) or mixed type ( n=6), and 1 case was located at the edge of the maxillary sinus. Totally 66.7% (34/51) of the ossifying focis contained peripherally hyperdense bone tissue and centrally hypodense adipose tissue, which corresponded to bone cortices and fatty marrow of the trabecular bone. And 96.1% (49/51) of the ossifying focis were attached to the adjacent bone of the sinus, and the sites of attachment were concordant with the actual origin of tumor confirmed in operation . Conclusions:Ossification can be seen in some sinonasal IPs. Tracing along ossifying focus to the site of attachment with sinus might facilitate preoperative prediction of the originating site of tumor.