Objective To analyze X-ray,CT and MRI characteristics of chondroblastoma.Methods Imaging(CT,X-ray and MRI)signs of chondroblastoma confirmed by pathology in 22 cases were analyzed.2 cases and 7 cases underwent contrast-enhanced CT and MRI examination respectivety.Results The lesions were located in tibia(n=11),femur(n=4),patella(n=2),humerus(n=1),temporal(n=1),mandibal(n=1),iliac bone with sacrum(n=1).X-ray manifestations were bone destruction(21),stripe or spotty calcification(5)and patchy sclerosis around the lesion(10).On CT,the lesions were lobular-and-oval(14),density of soft tissue(7)with stripe or spotty calcification(15),patchy sclerosis around(15)and soft tissue swelling(18).Mixed signal intensity on T2WI and FS T2WI,patchy long T1 and long T2 signal intensity around the lesions(20).Conclusion The imaging features of benign chondroblastoma are of certain characteristic and most signs on X-ray,CT and MR are corresponded with each other.

Objective To investigate the CT and MRI findings of granulomatosis with polyangiitis of the nasal cavity and paranasal sinus. Methods The CT and MRI features of eight patients of granulomatosis with polyangiitis in the nasal cavity and paranasal sinus confirmed by histo-pathology were analyzed retrospectively.CT scanning was performed in all eight patients.Routine MRI scanning was performed in seven patients.Dynamic contrast MRI was performed in three cases.SImax ,SIpeak ,Tpeak and MSI of the time-intensity Curves(TICs)were calculated.Results On CT scanning,bilateral middle turbinate,uncinate process and nasal septum were defected in 8 cases.Medial wall of bilateral maxillary sinus showed destruction and other walls of bilateral maxillary sinus showed sclerosis in 8 cases.The ethmoid labyrinth were involved in 6 cases in which the volume of maxillary sinus reduced.The collapse of nasal dorsum and flat nasal bone occured in 4 cases.Nasopharyngeal soft tissue was thicken in 2 cases.Theorbit was involved in 1 case.The mucosal thickness of all group of sinuses were showed in all 8 cases.On MRI scanning,peripheric mucosal of the lesions showed iso or long T1 and long T2 signal in 7 cases.Dynamic-enhanced MRI showed heterogeneous enhancement.TICs showed flat.But in one to four periods showed a slow rising gradient.SIpre was 1 030, SImax 2 500,SIpeak 2 353,Tpeak 100 s,and MSI 1.28%.Conclusion Granulomatosis with polyangiitis of the nasal cavity and paranasal sinus shows some typical CT and MRI features.To summarize the features is helpful to the diagnosis and therapy of the lesion.