Abstract
Objective: To compare the performance of transvaginal and transabdominal ultrasonography for diagnosis of uterine myoma using the results of transvaginal ultrasonography as the reference.
Methods: Our study subjects were 266 consecutive examinees who received both transvaginal and transabdominal ultrasonography at Aizawa Health Center during the period April 1 2014 to March 31 2015. The results of the two exams were compared, using the transvaginal method as the reference. The performance of the transabdominal approach in the diagnosis of uterine myoma was evaluated with particular regard to sensitivity, cause of non-diagnosis, localization and size of non-diagnosed lesions.
Results: Eight subjects with positive transabdominal but negative transvaginal ultrasonography findings were excluded, leaving 258 for the analysis. In 133 of the 258 subjects (52%), uterine myoma was detected by the transvaginal approach. The lesion was detected in 112 of them by the transabdominal method too. In other words, uterine myoma could be diagnosed by transvaginal ultrasonography alone in 21 subjects. The commonest cause of non-diagnosis by the transabdominal method was poor demarcation of the myoma (11/21, 52%). Intestinal gas accumulation was the next most common cause of non-diagnosis (9/21, 43%). Non-diagnosed lesions were frequently in the fundus. At 29.4 mm, the mean diameter of myomas detected by both the transvaginal and transabdominal approaches was significantly larger than that of myomas detected only by transvaginal method of 15.3 mm.
Conclusion: The sensitivity of transabdominal ultrasonography for diagnosis of uterine myoma was marginally lower than that of the transavaginal method. However, we consider that the transabdominal method can be used for first-line screening provided that its limitations are recognized.
