Objective To analyse MRI findings of AIDS dementia complex to improve the understanding of this disease.Methods Clinical and MRI data of 35 cases of AIDS dementia complex were analyzed retrospectively.Results The total of brain tissue of 31 cases was reduced and cerebral cortex and basal ganglia showed diffuse atrophy;the sulci broadened and ventricle expanded.Lateral ventricle white matter of 25 cases showed signal abnormalities.3 cases of simple brain atrophy.Conclusion AIDS dementia complex has characteristic MRI findings,most patients had signs of brain atrophy,the sulci broadened and ventricle expanded;lateral ventricle white matter and centrum semiovale showed signal abnormalitiesCombined with the clinical history,MRI examination had important significance for the early diagnosis of this disease.

We analyszed 108 examination papers that were taken when the students of 8 groups had finished theexercitation. The attainment was 73.6?4.4 points. Among the 400 selective questions, the difficult questions whichwere concentrated only on a few diseases accounted for 35.3%. There was mush difference between the proportion of theselective questions and that of the demands of the teaching program in different system of diseases. There was few or noselective question in the important diseases of the teaching program. It is suggested that the proposition of difficultquestions must include the important diseases in the teaching program. The diseases that are not commonly encountereddiseases may be deleted from the teaching program, but the commonly encountered must be put in the teaching program.It is necessary to reinforce the ability of students to analyse and resolve problems[

Objective To illustrate the CT,MRI and PET-CT features of spinal osteoblastoma,and provide an important reference for the preoperative diagnosis and assessment.Methods The imaging and clinical data in 16 cases of spinal osteoblastoma confirmed by surgery and pathology were analyzed retrospectively.Results Age of onset in 11 cases ranged from 10 to 29 years old,5 cases from 30 to 51 years old.Tumors were originated from the spine appendage in 13 cases,and from the vertebral bodies in 3 cases.Tumors presented as expansive bone destruction in 6 cases,and as osteolytic bone destruction in 10 cases.13 cases were diagnosed as benign diseases and 3 cases as invasive ones.Calcification or ossification was seen in all cases,with sclerotic margin of variable thickness and peripheral patchy high density of bone sclerosis.The soft tissue mass was found in 15 cases and intraspinal involvement was showed in 13 cases.The tumors showed isointensity or hypointensity on T 1WI,isointensity or hyper-intensity on T2WI in 13 cases,and showed heterogenous enhancement after contrast administration in 13 cases.PET-CT depicted the nodular or lobulated distribution of radioactive tracer with high radioactive concentration,with increment in standardized uptake value in 5 cases.Conclusion The typical imaging signs of spinal osteoblastoma were expansile,osteolytic bone destruction of the spine appendage,accompanying the soft tissue mass,with a speckled or nodular pattern of calcification or ossification within the lesions.Inhomogeneous signal intensity and inhomogeneous enhancement on MRI and nodular or lobulated high radioactive concentration for the tumors on PET-CT are found.