Objective To investigate the technique and application of nasolacrimal duct imaging using MR hydrography.Methods Eight healthy volunteers(16 lacrimal ducts)and 17 patients affected by primary epiphora(32 lacrimal ducts)underwent MRl with three.dimensional fast recovery fast spin echo (3D-FRFSE)MR dacryocystography(MRD)sequence after sterile saline solution had been instilled into the conjunctival sac.For all patients affected by primary epiphora,FRFSE T2-weighted oblique coronal and axial images were obtained after MRD.All patients(32 lacrimal ducts)underwem lacrimal endoscopy.which served as a standard of reference for confirming MR findings.Results Eight cases of 16 normal lacrimal passages were showed by MR hydrography with administering topical sterile saline solution,which demonstrated the lacrimal sac well and whole course of the nasolacrimal duct.Endoscopic findings confirmed nasolacrimal duct obstruction secondary to chronic non-specific inflammation:the color of the mucosa of the nasolaerimal ducts was grey-red,and the obstructive sinuses were filled with nonelastic grey-white membrane.The accuracy of 3D-FRFSE MRD sequence in diagnosing obstructive level was 78%(25/32). The lacrimal ducts above the obstructive level showed watery hypo-intensity on 3D-FRFSE MRD.and the lacrimal ducts below the obstructive level could not be showed.Abnormal findings were presented in all cases of obstructive nasolacrimal ducts with Axi-FRFSET2 WI and Cor-FRFSET,WI sequences:long T2 fluid signals were seen in the lumens of tlle lacrimal sac and(or)nasolacrimal duct above the obstructive level. equal or slightly long T2 soft-tissue signals were seen in the lumens of the nasolaerimal duct below the obstructive level.and the mucosa of the ducts thickened Conclusion MR imaging performed after the topical administration of sterile saline solution can reveal normal nasolacrimal duct and is feasible in evaluating obstructive nasolacrimal ducts.

Objective To investigate the change of diffusion tensor imaging (DTI) parameters on extracorticospinal tract and some domain in Parkinson disease (PD), and to explore the relationship between DTI parameters and PD. Methods Ten PD patients with unilateral symptoms and 20 with bilateral symptoms were enrolled in PD group 1 and PD group 2, respectively. Control group included 30 volunteers whose age and sex matched with those of PD group. PD patients and the subjects in control group underwent routine MR plain scan and DTI scan. FA and ADC maps were obtained after postprocessing. FA values and ADC values of ROI (region of interest) were measured. ROI included substantia nigra (SN), red nucleus (NR), globus pallidus (GP), putamen (PUT), caudate nucleus (CN), thalamus, genu of corpus callosum, splenium of corpus callosum, callosal gyrus, white matter of frontal lobe and anterior centra gyrus. All data were analyzed statistically. Results FA value of SN, CN, thalamus and splenium of corpus callosum of PD group degraded obviously compared with that of control group (P<0.05). FA value of PD group 1 was lower than control group and PD group 2 at anterior central gyrus and callosal gyrus (P<0.05). There was no significant difference of FA value among PD groups and control group at other ROI's. There was negative correlation between the changes of FA value at SN and PD grade. No significant difference was found in ADC value among PD group 1, PD group 2 and control group, but there was an increasing tendency of ADC value along with the progress of PD. Conclusion FA values of SN, CN, thalamus and splenium of corpus callosum can offer some important information for the early diagnosis of PD. DTI is useful for the study about PD's pathomechanism and clinical manifestation in vivo.