Analysis of clinical and ultrasonic manifestations of schwannomas in different anatomical locations

YANG Fan; LIU Jingyuan; CHEN Yuan; WU Huolin

Abstract：Objective To investigate the clinical and ultrasonic manifestations of schwannomas in different anatomical loca-tions.Methods Sixty-eight patients with 73 superficial schwannomas confirmed by surgery and pathology were retrospectively analyzed.They were divided into subcutaneous,intramuscular and intermuscular groups according to their anatomical locations,and the clinical and ultrasonic manifestations of each group,including Tinel's sign,rat tail sign,vessel accompanying sign,split fat sign,and ultrasound diagnostic rate,were compared.Results There were 10 cases of subcutaneous schwannomas,16 of intramuscular schwannomas,and 47 of intermuscular schwannomas.The positive rates of Tinel's sign(27/47,57.4%),rat tail sign(38/47,80.6%)and vessel accompanying sign(29/47,61.7%)of intermuscular schwannomas were higher than those of intramuscular schwannomas(3/16,18.8%),(2/16,12.5%),(2/16,12.5%)and subcutaneous schwannomas(1/10,10.0%),(2/10,20.0%),(1/10,10.0%),the positive rate of split fat sign of intramuscular schwannomas(13/16,81.3%)was higher than that of intermuscular schwannomas(9/47,19.1%),and the ultrasonographic diagnosis rate of subcutaneous schwannomas(3/10,30.0%)was lower than that of intermuscular schwannomas(39/47,83.0%)and intramuscular schwanno-mas(13/16,81.3%),all the differences were statistically significant(P<0.05).Conclusions Schwannomas located in differ-ent anatomic sites may have different clinical and ultrasonic manifestations due to the difference of the involved nerve size and adjacent tissue structure.