Transcranial Sonography Image Characteristics In Different Parkinson Disease Subtypes

Objective:Parkinson disease(PD)has been classified into three subtypes:postural instability gait difficulty(PIGD),tremor dominate(TD)and INDETERMINATE PD.Transcranial sonography(TCS)is considered to be an important tool to diagnose PD.However it is uncertain that whether there are differences in TCS image characteristics in different PD subtypes.Methods:From September 2013 to December 2016,373 inpatients or outpatients(188 PIGD,108 TD,77 INDETERMINATE PD)were registered.Sonographic alteration and clinical characteristic among the three groups were analyzed.Results:14 subjects(6 PIGD,7 TD,1 INDETERMINATE PD)were excluded due to poor temporal window,and 3 subjects were excluded for the different TCS results of two sonologists.Totally,356 subjects were included and were divided into three groups:180 PIGD,101 TD and 75 INDETERMINATE PD with matched age and sex.(1)PIGD patients had more serious disease than TD and INDETERMINATE PD group(P<0.001 for H-Y staging and P<0.001 for UPDRS ? score).(2)Comparing TD and INDETERMINATE PD group,PIGD group always had larger substantia nigra(SN)hyperechogenicity areas on TCS(the right side:P =0.029,the left side:P= 0.023 and the largest side:P= 0.008),the difference was statistically significantand(P<0.05).We also found that there was no correlation between SN hyperechogenicity with disease duration or severity(P>0.05).(3)SN hyperechogenicity(91.1%,164/180 VS 79.2%,80/101 VS 80.0%,60/75)and abnormal brainstem raphe signal(17.2%,31/180 VS 9.9%,10/101 VS 9.3%,5/75)were more often in PIGD group than in TD and INDETERMINATE PD group(P = 0.001,P = 0.041),the difference was statistically significantand(P<0.05).Also there was no significant difference in lenticular nucleus hyperechogenicity and the rate of abnormal third ventricle width in the three group(P>0.05).Conclusion:PIGD patients have more serious diseases than TD and INDETERMINATE PD group.They always have larger SN hyperechogenicity areas on TCS and we find that there is no correlation between SN hyperechogenicity with disease duration or severity.Similarly,abnormal brainstem raphe signal is also more often in PIGD group than in TD and INDETERMINATE PD group,which may imply that PIGD group is vulnerable to suffer from depression in the future.