RESUMO
Objective To study the MRI findings of superficial siderosis of the central nervous system(SSCNS)and to improve the understanding of SSCNS imaging features.Methods MRI images of 21 cases were retrospectively reviewed.MRI plain scan (T1WI,T2WI)and diffusion weighted imaging(DWI)were performed in all patients;T2* weighted angiography(SWAN)scan was performed in 8 patients.Results On T1WI of 21 cases,only 4 cases showed infratentorial superficial siderosis which appeared as linear hypointense signal in sulci cerebelli and around brainstem.On T2WI of 21 cases,18 cases presented with linear hypointense signal on cerebral surface.On DWI of 21 cases,20 cases showed linear hypointense signal on cerebral surface,and the other one case showing negative signal on DWI presented hypointense signal on SWAN.On SWAN of 8 cases,more lesions were found in more regions.Conclusion SSCNS has characteristic findings on MRI.SWAN is sensitive to superficial siderosis.MRI is a reliable method for the assessment of SSCNS.
RESUMO
Objective To explore the value of enhanced T2 *-weighted angiography (ESWAN) sequence in displaying the intracranial deep vein distension in full-term neonates with hypoxic-ischemic encephalopathy (HIE).Methods Thirty-two confirmed cases of full-term neonates confirmed with HIE and 10 cases of normal full-term neonates received the brain magnetic resonance imaging(MRI) ESWAN sequence scanning.The display rate of intracranial deep vein in normal group and HIE group with mild,moderate and severe degree was evaluated.The differences in intracranial deep vein display rate between the normal group and the HIE group or within different degrees of HIE patients were compared respectively to observe the relationships between intracranial ischemic lesion and deep vein conditions.The role of ESWAN sequence in the diagnosis of HIE was evaluated.Results The display rate of intracranial deep vein in normal group was 26.2％ (21/80 cases) ;the display rate of intracranial deep vein in mild,moderate and severe HIE groups were 59.8％ (67/112 cases),92.3％ (96/104 cases) and 95.0％ (38/40 cases),respectively.The differences of intracranial deep vein display rate between normal group and mild HIE group were statistically significant (P ＜ 0.05) ; the differences of intracranial deep vein display rate between the slight HIE group and moderate HIE group were statistically significant (P ＜ 0.05) ;the differences of intracranial deep vein display rate between the moderate HIE group and severe HIE group were not statistically significant(P ＞ 0.05).The distribution of intracranial deep vein distension and ischemic lesion in HIE group was consistent.Conclusions ESWAN sequence can clearly show the relationship between intracranial venous distension and ischemic lesion,which has diagnostic value in judging the location and extent of HIE.It can indicate the severity of HIE by displaying secondary distension of intracranial vein.