Evolution rules and clinical value of apparent diffusion coefficient in cerebral infarction / 中南大学学报(医学版)

OBJECTIVE@#To determine the rules that apparent diffusion coefficient (ADC) changes with time and space in cerebral infarction, and to provide the evidence in defining the stage, guiding treatment or judging the prognosis in infarction.@*METHODS@#Eighty-eight work-ups in 69 patients with cerebral infarction (8 hyperacute, 35 acute, 20 subacute, and 25 chronic infarctions) were imaged with both conventional MRI and diffusion weighted imaging. The average ADC, the average relative ADC (rADC), and the ADC or rADC from the center to the periphery of the lesion were calculated.@*RESULTS@#The average ADC and the average rADC of hyperacute and acute infarction lesion depressed obviously. The average ADC and the average rADC of subacute infarction lesion were significantly higher than those of hyperacute and acute infarction lesion (P < 0.05), and some approached the values of uninjured side which appeared "pseudonormal values" at 10 to 14 days. The average ADC and the average rADC in chronic infarction lesion were the highest (P < 0.05). The longer the prognosis, the higher the average ADC and the average rADC of infarction lesion. The ADC and the rADC in 7 hyperacute and 26 acute lesions had gradient signs that these lesions increased from the center to the periphery. The ADC and the rADC in 15 subacute lesions had adverse gradient signs that these lesions decreased from the center to the periphery.@*CONCLUSION@#The ADC and the rADC of infarction lesions have evolution rules with time and space corresponding to the pathophysiological foundation. The evolution rules with time and those in space can be helpful to decide the clinical stage and pathophysiological phase of infarction, and to provide the evidence in guiding the treatment or judging the prognosis in infarction.

MRI diagnosis of cerebral sparganosis / 中华放射学杂志

Objective To analyze and evaluate the characteristics of cerebral sparganosis on MRI. Methods MRI appearances of 15 cases of cerebral sparganosis proven by pathology or serological test were retrospectively studied.Results A total of 21 lesions were found,some of them were single and some were multiple but asymmetrical.8 lesions were found in parietal lobe,6 in frontal lobe,2 in temporal lobe,2 in oceipital lobe,1 in basal ganglia,1 in cerebellar hemisphere and 1 in pons.The lesions carried slightly hypointense on T_1-weighted images and moderate hyperintense on T_2-weighted images.Most lesions showed pefilesional brain parenchyma edema.Enhanced MRI was performed in 10 cases,and all of them demonstrated abnormal enhancement such as peripheral ring-type,tortuous beaded shape or serpiginons tubular shape enhancement.Follow-up MR images in 6 eases were analyzed,and the location and shape of the lesions changed in 2 of them.Conclusion There are some specific MRI findings on cerebral sparganosis.Enhanced MRI and follow-up examination are important for the diagnosis of cerebral sparganosis.