start-ver=1.4 cd-journal=joma no-vol=47 cd-vols= no-issue=2 article-no= start-page=147 end-page=152 dt-received= dt-revised= dt-accepted= dt-pub-year=2011 dt-pub=201102 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Diagnostic value of dynamic contrast-enhanced MRI for unilocular cystic-type ameloblastomas with homogeneously bright high signal intensity on T2-weighted or STIR MR images en-subtitle= kn-subtitle= en-abstract= kn-abstract=Typical MR images of ameloblastomas on T2-weighted image (WI) or short inversion time inversion-recovery (STIR) show multiple bright high-signal-intensity loci on a high-signal-intensity background. Unilocular cystic-type ameloblastomas show homogeneously bright high signal intensity on T2WI or STIR as a water-like signal intensity. Therefore, it is difficult to distinguish unilocular cystic-type ameloblastoma from other cystic lesions such as keratocystic odontogenic tumors, radicular cysts (residual cysts) and dentigerous cysts only on the basis of MRI signal intensity. In the present study, we evaluated whether contrast-enhanced (CE)-T1WI and dynamic CE-MRI (DCE-MRI) could provide additional information for differential diagnosis in unilocular cystic-type ameloblastoma. Images from 12 cases of suspected unilocular cystic-type ameloblastoma were evaluated in the present study. Of them, 5 had areas suspected of indicating a solid component on T1WI and T2WI (or STIR). Ten had undergone additional CE-T1WI and DCE-MRI. On 5 of 10 cases of CE-T1WI, a tiny enhancement area was detected. On 6 of 10 DCE-images, a time-course enhanced area which was suspected to be a solid component was detected. CE-T1WI was helpful in the diagnosis of ameloblastoma because the tiny enhanced areas were taken to indicate possible solid components. Moreover, the rim-enhancement area on CE-T1WI could be divided into small regions of interest, and some of these showed slightly increased enhancement on DCE-MRI, which was taken to indicate a solid component and/or intramural nodule with focal invasion of ameloblastoma tissue. DCE-MRIs of the four remaining cases, which provided no clues to the diagnosis of ameloblastoma in the manner of the above descriptions, showed thicker rim enhancement than odontogenic cysts. Thus, CE-T1WI and DCE-MRI were helpful in the differential diagnosis of unilocular cystic-type ameloblastomas with homogeneously bright high signal intensity on T2WI or STIR. en-copyright= kn-copyright= en-aut-name=HisatomiMiki en-aut-sei=Hisatomi en-aut-mei=Miki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=YanagiYoshinobu en-aut-sei=Yanagi en-aut-mei=Yoshinobu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=KonouchiHironobu en-aut-sei=Konouchi en-aut-mei=Hironobu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=MatsuzakiHidenobu en-aut-sei=Matsuzaki en-aut-mei=Hidenobu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=TakenobuToshihiko en-aut-sei=Takenobu en-aut-mei=Toshihiko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=UnetsuboTeruhisa en-aut-sei=Unetsubo en-aut-mei=Teruhisa kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=AsaumiJun-ichi en-aut-sei=Asaumi en-aut-mei=Jun-ichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= affil-num=1 en-affil= kn-affil=Okayama Univ, Grad Sch Med Dent & Pharmaceut Sci, Field Tumor Biol, Dept Oral & Maxillofacial Radiol affil-num=2 en-affil= kn-affil=Okayama Univ Hosp, Dept Oral Diag & Dentomaxillofacial Radiol affil-num=3 en-affil= kn-affil=Okayama Univ Hosp, Dept Oral Diag & Dentomaxillofacial Radiol affil-num=4 en-affil= kn-affil=Okayama Univ Hosp, Dept Oral Diag & Dentomaxillofacial Radiol affil-num=5 en-affil= kn-affil=Okayama Univ, Grad Sch Med Dent & Pharmaceut Sci, Field Tumor Biol, Dept Oral & Maxillofacial Radiol affil-num=6 en-affil= kn-affil=Okayama Univ, Grad Sch Med Dent & Pharmaceut Sci, Field Tumor Biol, Dept Oral & Maxillofacial Radiol affil-num=7 en-affil= kn-affil=Okayama Univ, Grad Sch Med Dent & Pharmaceut Sci, Field Tumor Biol, Dept Oral & Maxillofacial Radiol en-keyword=Ameloblastoma kn-keyword=Ameloblastoma en-keyword=Unicystic kn-keyword=Unicystic en-keyword=Sold/multicystic kn-keyword=Sold/multicystic en-keyword=MRI kn-keyword=MRI en-keyword=DCE-MRI kn-keyword=DCE-MRI en-keyword=Odontogenic tumor kn-keyword=Odontogenic tumor en-keyword=Odontogenic cyst kn-keyword=Odontogenic cyst END