| Background The clinical course of thyroid associated ophthalmopathy(TAO),the autoimmune disease of retro-ocular tissues,is well known.During the active state, TAO is characterized by oedematous swelling and dysfunction of the extraocular muscles,and expansion of orbital connective tissue.Unfortunately,muscles remain thick during the subsequent inactive phase,causing persistent proptosis,making it impossible to assess disease activity by imaging techniques which provide only size information. To make a distinction between active and inactive disease is essential for treatment decisions,since patients in active stage will benefit from immunosuppressive treatment,i.e.corticosteroids and/or irradiation of the retrobulbar spaces,while those with inactive disease will not.In the latter case eye surgery,or orbital connective tissue removal should be considered.Therefore,diagnostic techniques which can assess disease activity have an essential role in the estimation of the phase and severity of the retrobulbar autoimmune process.For the usual ophthalmological clinical examination,as far as imaging is concerned,up to now two approaches of nuclear medicine have been utilized:111In or 99Tcm Octreo-Scan.Because these methods for the estimation of disease activity in the orbits of patients with TAO have the disadvantages of being either expensive or time consuming,so they can not be popular in the clinnical examination.Through a comparative study of 99Tcm-DTPA and 99Tcm-OCT SPECT orbital imaging,evaluated the clinic significance of two imaging in estimating activity of TAO.The aim of this study was to develop a new method:simple,rapid and costefficient method for staging patients with TAO.Objective Through a comparative study of 99Tcm-DTPA and 99Tcm-OCT SPECT orbital imaging,evaluated the clinic significance of two imaging in estimating activity of TAO.Methods Acording to the clinnic activity score(CAS),26 TAO patients were divided into 2 groups:active group(CAS≥3) and inactive group(CAS＜3),14 volunteers (Control group)participates this study.Orbit scan were completed after intravenously injection with 99Tcm-DTPA740MBq and 99Tcm-OCT 740MBq(every other day). Obtaining the uptake ratio of two kinds of orbit scans.The statistical analyses included Paired-samples T Test analysis of variance and Spearman regression analysis.Results There is no statistically significance between the two methods in UR(t=0.075 p＞0.05).There is a statistically significant correlation was found between CAS and the uptake ratios(99Tcm-DTPA:r=0.835 p＜0.001;99Tcm-OCT.r=0.912, p＜0.001).But there is no significant difference between two tracers in the same group of UR(p＞0.05).Conclusions1 There is a good uniformity between 99Tcm-DTPA and 99Tcm-OCT orbital scan.2 There is a good uniformity between CAS and both imagings which can become the clinnical assesment of disease activity3 99Tcm-DTPA is a feasible and maybe a new promising estimation method of activity in the patients with TAO. |
PDF Full Text Request