Diagnostic value ofmulti-slice CT in the spasmodic torticollis before operation

Abstract

：Objective To explore themethod and its clinical value of Multi-slice CT (MSCT) in spasmodic torticollis (ST).Methods Thirty-three cases of spasmodic torticollis, including rotational type (18 cases,55%), laterocollis(10 cases, 30%), bilateral retrocollis(5 cases, 15%), and the other 42cases of normal persons as controls were studied using MSCT. The thickness of each pairedcervical muscles in images were measured and compared. If hypertrophied muscles were foundin different types of ST, the incrassated values on CT images and amplitude with EMGexamination were measured and analyzed using Pearson's correlation test. Results (1) CTfeatures of all 33 cases of ST correlated with its clinical types. The hypertrophiedmuscles in rotational type were distributed in the 1/4 postero-lateral region ofrotational side and the 1/4 antero-lateral region of opposite side. The hypertrophiedmuscles in laterocollis were mainly distributed in the postero-lateral and antero-lateralregion of same side. And the hypertrophied musles in laterocollis were distributed in the1/4 postero-lateral region of both sides. (2) The thickness of cervical muscles could bemeasured correctly on axial CT images. The means of thickness of each paired cervicalmuscles in rotanional type and laterocollis showed significant differences(t = 2. 482～6.540, P < 0. 05)The means of thickness of obliquns inferior, splenius capitis andsemispinalis capitis in bilateral retrocollis showed significant differences with that ofthe normal group(F =4. 947～15.713, P <0.01)Theincreasing values of thickness of hypertrophied muscles on CT images and its amplitudewith EMG examination showed positive correlation (r=0.713～0.963, P<0.01) (3) The results of MSCT and EMGexamination could provide a basis of strategy for surgical treatment and improve thecurative effect. Conclusions MSCT can clearly and definitely show the morphological changeof cervical muscles in ST, and show the hypertrophied muscles distributing orderly, whichmay be helpful for doing next EMG examination and knowing the muscles correlated nearlywith convulsion. MSCT is the first important noninvasive examination for diagnosis andevaluation of ST. Key words: Spasmodic torticollis; Tomography, X-ray computed; Electromyography