Tissue Segmentation And Quantitative Analysis Of Orbital Cube-flex MRI In Patients With Thyroid-associated Ophthalmopathy

Part ⅠQuantitative analysis of orbital soft tissue by using Cube flex imaging in patients with thyroid-associated ophthalmopathyPurpose: To explore the feasibility and application value for quantitative analysis of disease condition and post-treatment changes in patients with TAO based on cube flex imaging.Material and Methods: 20 healthy volunteers and 20 TAO patients were included.Healthy volunteers underwent Cube flex imaging twice within 1week,and Bland-Altman analysis was used to assess the consistency of extraocular muscle water fraction and volume.All TAO patients performed cube flex before and after methylprednisolone pulse therapy(MPPT)to obtain orbital soft tissue water fraction and volume values,and recorded clinical activity scores(CAS).Two independent sample t tests were used to compare the differences between Pre-TAO patients and the control group.Paired sample t tests were used to compare the differences in orbital soft tissue water fraction and volume before and after MPPT treatment.The therapeutic effect of MPPT is defined as:[CAS improvement rate =(CAS before treatment-CAS after treatment)/CAS before treatment].The Pearson correlation coefficient test was used to analyze the correlation between extraocular muscle and orbital fat measurements and CAS and CAS improvement rates in TAO patients before treatment.Results:(1)Extraocular muscle volume and water fraction obtained from two cube flex imagings of healthy volunteers have high consistency.(2)The extraocular muscle and orbital fat water fractions and volume of TAO patients before treatment were significantly higher than controls(P<0.05);After MPPT,the extraocular muscle and orbital fat water fractions and volume of TAO patients were decreased significantly(P<0.05).(3)The maximal water fraction of extraocular muscle in Pre-TAO patients was positively correlated with CAS and CAS improvement rates(CAS:left,r=0.822;right,r=0.833;CAS improvement rates:left,r=0.611;right,r=0.616);(5)the orbital fat water fraction of Pre-TAO patients was positively correlated with CAS before treatment(left,r=0.507,right,r=0.623).Conclusions:(1)The measured values using Cube Flex imaging is consistent with the pathophysiological changes of TAO.(2)The changes in volume and Wa F of orbital soft tissue are both consistent with the response of TAO patients to MPPT,which can provide an objective basis for evaluating the effects of MPPT.Part ⅡDifferentiation of orbital soft tissue in thyroid-associated ophthalmopathy based on the efficacy of methylprednisolone pulse therapyPurpose: To quantitatively analyze the changes of orbital soft tissue parameters between improvement and no-improvement TAO with MPPT by using cube flex technology,and to find imaging indicators that can predict the effect of MPPT treatment.Material and Methods: 17 improvement TAO patients and 20no-improvement TAO patients were included.Two independent sample t test was used to observe the difference in cube flex measurements between two groups.Results: 1.compared to the no-improvement TAO patients before MPPT,improvement TAO patients,the mean value of extraocular muscle and orbital fat water fraction in the improvement group was significantly higher(P<0.05),and there was no significant statistical difference in extraocular muscle and orbital fat volume(P>0.05).2.Comparison of improvement ratio(IR)between improvement and no-improvement TAO patients: the water fraction IR of extraocular muscles and orbital fat,WOIR,OFIR,and ETMIR in improvement group was significantly higher than in no-improvement group(P <0.05).Conclusions: TAO Patients with higher water fration of extraocular muscles based on cube flex imaging have more obvious effects on MPPT,which can be used as an auxiliary method to predict the effect of MPPT.Part Ⅲ A Cube flex imaging study of orbital soft tissue structure in patients with dysthyroid optic neuropathyPurpose: to observe the changes of orbital soft tissue in patients with thyroid-associated ophthalmopathy(TAO)without optic neuropathy and in patients with dysthyroid optic neuropathy(DON)by using cube flex imaging.Material and Methods: 20 DON patients,20 TAO patients without optic neuropathy were included,cube flex examinations were performed on all of the subjects.Two independent sample t test was used to observe the difference in cube flex measurements between two groups.Results: After MPPT,the average and maximum values of extraocular muscle and orbital fat water fraction,orbital fat volume in DON were significantly decreased(P<0.05);there was no statistical difference in extraocular muscle volume before and after treatment(P> 0.05).After MPPT,the average and maximum values of extraocular muscle and orbital fat water fraction,orbital fat volume in TAO without optic neuropathy were significantly decreased(P<0.01);there was no statistical difference in extraocular muscle volume before and after treatment(P>0.05).Compared to TAO without optic neuropathy before MPPT,DON showed increased in average values of extraocular muscle and orbital fat water fraction,extraocular muscle volume(P<0.01);there was no significant difference in orbital fat volume and optic nerve volume(P>0.05).Conclusions:(1)The orbital soft tissue inflammatory edema of TAO is an important risk factor for the occurrence of DON,so the orbital soft tissue water fraction is an important indicator for the monitoring of the occurrence of DON.(2)The extraocular muscle volume of DON is significantly higher than TAO without optic neuropathy,suggesting that mechanical compression is the main factor of optic nerve injur.