Objective To investigate the imaging findings of oblique vaginal septum syndrome and its diagnostic value.Methods Clinical and radiographic data of 13 patients with oblique vaginal septum syndrome were analyzed retrospectively and relevant literatures were reviewed.All 13 patients underwent ultrasonography examination preoperatively,and 8 of them underwent MRI examination,and 3 patients underwent CT examination as well.The position of the oblique septum,the size of the cavity in the rear of oblique septum, the positional relationship between the cavity in the rear of oblique septum and the cervix,and the concomitant changes of the uterine appendages and urinary system were analyzed.Results The ultrasonography and MRI examinations all manifested as uterus didelphys,cervix duplex,double vagina and obstructed hemivagina,and oblique septum originated from the middle of cervix duplex and attached to one side of the vaginal wall,shielding the ipsilateral cervix;oblique vaginal septum was on the right side in 4 cases and on the left side in 9 cases;the average volume of the cavity in the rear of oblique septum in 6 cases of type Ⅰ was 255 mL,and the average volume in 6 cases of type Ⅱ was 74 mL,and the volume in 1 case of type Ⅲ was 56 mL;2 cases were combined with ipsilateral hematosalpinx and 1 case was combined with a chocolate cyst of ipsilateral ovary;12 cases were accompanied with ipsilateral renal agenesis and 1 case was accompanied with ipsilateral renal hypoplasia.CT examinations of 3 cases all presented as uterus didelphys,a cystic hypodensity lesion under unilateral cervix and ipsilateral renal agenesis.Conclusion Imaging findings of oblique vaginal septum syndrome are quite characteristic. Ultrasonography,CT and MRI examinations have certain value for accurate diagnosis of the disease.

Objective To investigate the imaging findings and clinicopathological features of osteofibrous dysplasia(OFD)in tibia.Methods The imaging findings of 1 0 cases with OFD in tibia,which were confirmed by pathology and had complete clinical data were analyzed retrospectively.Results The disease occurred in children and the main clinical manifestations were anterior mass and arch deformity of calf.X-ray and CT examinations showed that the lesion distributed along the long axis of tibia and the anterior cortex was involved in 9 cases and the posterior cortex was involved in another one;the midpiece of tibia was involved in 7 cases and the lesion located at the junction area between upper third and middle third of tibia in another 3 cases;9 cases showed multilocular osteolytic lesions within the expanded cortex,manifesting as the high-density bony intervals of different thickness among a number of low-density lesions and another one presented as unilocular osteolytic lesion with sclerosis rim.Lesions manifested as multiple bubble-like intermediate or high signal intensity foci and low-signal interval bands on T2WI in 3 cases of MRI examinations.Microscopic examinations revealed that the lesion was composed of fibrous tissue and trabecular bone,fibrous tissue varied from sparse to dense and trabecular bone was surrounded by a great many osteoblasts and osteoclasts of vary number.The lesion presented as band-shaped distribution with more fibrous tissue and less trabecular bone in the central zones (corresponding to osteolytic destruction areas in radiography)and with trabecular bone gradually increasing in the peripheral zones to form abundant merged lamellar bone (corresponding to bony intervals in radiography).Conclusion OFD in tibia is characterized by the high-density bony intervals(low-signal interval bands on T2WI)of different thickness among a number of low-density lesions(multiple bubble-like intermediate or high signal intensity foci on T2WI)within anterior cortex, which reflects the pathological changes.Typical cases can be diagnosed with a variety of imaging findings and clinical features.

Objective: To investigate the imaging features of adult bones Langerhans cell histiocytosis (LCH). Methods: The DR, CT, and MRI findings of 25 adults patients with LCH from January 2008 to June 2019 in Yueqing Sixth People′s Hospital of Zhejiang Province (3 cases), Yueqing Third People′s Hospital of Zhejiang Province (7 cases) and Wenzhou People′s Hospital of Zhejiang Province (15 cases) were retrospectively analyzed. Results: Among the 25 patients, the lesions located in the skull in 5 cases, in the spine in 5 cases, in the long bones in 10 cases, in the other flat bones in 3 cases, and in multiple bones in 2 cases. DR features (17 cases) showed: cystic destruction in 11 cases (6 cases with dilated changes), osteolytic damage in 6 cases; peripheral bone cortex thickening in 5 cases, bone lesions with less smooth inner edge in 4 cases, soft tissue mass around the lesion in 12 cases; 'hole set cave sign' in 2 cases, 'flat vertebra' in 2 cases, and 'button-like dead bone' in 1 case. CT features (15 cases) showed: cystic destruction in 9 cases (5 cases with dilated changes), osteolytic damage in 6 cases; 'hole set cave sign' in 2 cases, 'flat vertebra' in 2 cases, and 'button-like dead bone' in 1 case. MRI features (14 cases) showed: cystic destruction in 9 cases (5 cases with dilated changes), osteolytic damage in 5 cases; in the bone destruction area, 8 cases had low T₁WI signal and high T₂WI signal, 4 cases had equal T₁WI signal and higher mixed T₂WI signal, 2 cases had slightly higher T₁WI signal and higher mixed T₂WI signal; STIR lipoprotein sequence showed high signal in 11 cases, and isointense signal in 3 cases; DWI showed high signal. Conclusions The imaging performance of adults LCH has certain characteristics, and the diagnostic accuracy can be improved according to the imaging performance and the clinic.