Objective:

To explore the characteristic of conventional ultrasound and contrast-enhanced ultrasound (CEUS) of mummified thyroid nodule (MTN)

in order to avoid to misdiagnosis as malignant nodules.

Methods:

A total of 38 cases of MTN patients and 42 cases of papillary carcinoma of the thyroid (PTC) patients were enrolled. The size

echogenicity

margin

aspect ratio

blood flow signal

calcification morphology

calcification

location

double ring sign

and the enhancement patterns for each nodule were obtained to be compared between groups

and the efficiency of the specific sonographic signs of MTN for diagnosis of MTN were observed.

Results:

During the follow-up

the size of MTN were significantly decreased (

P

＜0.05)

and the reduction rate is (714)%. There were statistically significant differences of aspect ratio

calcification morphology

calcification location

blood flow signal

double ring sign

and the enhancement patterns between groups (all

P

＜0.05)

but not of echogenicity and margin of the nodules between groups (both

P

＞0.05). The specificity and positive predictive value of no enhancement pattern of CEUS for diagnosing MTN were all 100.00%.

Conclusion:

The contrast of previous ultrasound images and peripheral massive calcification (arc

annulus

eggshell)

double ring sign and no enhancement pattern of CEUS are helpful for the diagnosis of MTN and the efficiency of CEUS for diagnosing MTN was significantly higher.