Purpose or Case Report: Contrast-enhanced ultrasound (CEUS) and shear wave elastography (SWE) have been widely studied in adult thyroid disease. However, evaluation of thyroid nodules using these tools in pediatric patients has yet to be published.
We aim to evaluate the feasibility and safety of CEUS and SWE for thyroid nodules in children at the time of cytologic biopsy.
Methods & Materials: An IRB approved prospective pilot study of children who underwent US-guided thyroid nodule biopsy was performed. SWE protocol; 9 mHz GE EPIQ E9 linear probe, regions of interest placed on nodules and normal thyroid gland (as a control) to obtain an SWE value. CEUS protocol; 9 mHz linear probe, 0.03 ml/kg Lumason, mechanical index 0.12, dynamic imaging of thyroid nodule and normal thyroid for 2 minutes. Average contrast intensity over 2 minutes was used to generate a time-to-peak (TTP) enhancement curve. Inclusion criteria was any patient who underwent thyroid biopsy under sedation/anesthesia due to the presence of a pre-existing IV which could be used for CEUS. Exclusion criteria included simple thyroid cysts or diffuse thyroid abnormality.
Results: At initiation of protocol, 5 consecutive patients (4F, 1M) were included (5 SWE, 4 CEUS). Mean patient age was 16.6 years (9-20). 9 nodules was included. Mean maximal diameter of nodule was 21 mm (5-26). There were 5 solid and 4 solid/cystic nodules.
There were 6 Bethesda grade 2 (hyperplastic) nodules, 2 Bethesda grade 3 (follicular lesion of undetermined significance) nodules and one organizing hematoma. SWE values were higher in the nodule compared to normal thyroid gland in 2/5 patients (p <0.05), follicular lesion of undetermined significance and organizing hematoma. SWE values were trending toward significance in 3/5 patients, (p 0.05-0.069), all hyperplastic nodules.
For CEUS, mean TTP of normal thyroid was 6.9 secs (5.8-8), for Bethesda grade 2 nodules was 7.0 secs (6-7.9) and for Bethesda grade 3 nodules was 6.9 secs (5.8-8). There was no statistically significant difference between TTP of normal thyroid compared to thyroid nodules (p = 0.27).
Conclusions: This is the first evaluation of CEUS and SWE characterization of thyroid nodules in children. This pilot study demonstrates that SWE and CEUS is safe and technically feasible for evaluation of thyroid nodules in children. A larger cohort is needed for imaging validation and is ongoing.