Use of 3-dimensional sonography for prenatal evaluation and follow-up of fetal goitrous hypothyroidism.
OBJECTIVE
Fetal goitrous hypothyroidism is a rare and potentially lethal condition. Consequently, its early diagnosis and treatment improve prognosis. Thyroid hormone measurement in either fetal serum or amniotic fluid implies important risks. Here we present a fetal goiter and the follow-up procedure, both done by the traditional method and by using 3-dimensional power Doppler (3DPD) imaging and virtual organ computer-aided analysis (VOCAL).


METHODS
A single well-documented case of fetal goiter was followed weekly from 22 weeks until delivery. Amniocentesis for thyrotropin (TSH) and free thyroxine (T(4)) measurement as well as levothyroxine injections were performed at every control. In addition to amniocentesis, every control involved a sonographic evaluation, which included standard measurements of the gland and the capture of volume image sets in gray scale and 3DPD. Volume calculation of the gland was done using VOCAL software. Vascularization of the gland was evaluated by the vascularization index (VI) included in the software.


RESULTS
With treatment, TSH levels decreased progressively until normalization. Free T(4) levels increased toward the end of gestation. Sonographic measurements of the gland volume to estimated fetal weight ratio decreased across treatment as levels of TSH did. The VI clearly depicted the vascular regression of the goiter, decreasing throughout treatment in a consistent way until 24 hours before delivery.


CONCLUSIONS
Gray scale and 3DPD evaluations of the thyroid gland have been validated under similar circumstances and might be reliable complements to the invasive methods used in the management of this fetal condition.
Marín
Rodrigo Cuevas
RC
Fetal Medicine Unit, Vall d'Hebron University Hospital, Universidad Autónoma de Barcelona, Barcelona, Catalunya, Spain.
Bello-Muñoz
Juan Carlos
JC
Martínez
Gabriel Villagómez
GV
Martínez
Silvia Arévalo
SA
Moratonas
Elena Carreras
EC
Roura
Lluis Cabero
LC
D000328:Adult; D000649:Amniocentesis; D015415:Biomarkers / Q000032:analysis; D003937:Diagnosis, Differential; D005260:Female; D005315:Fetal Diseases / Q000000981:diagnostic imaging*; D006042:Goiter / Q000000981:diagnostic imaging*; D006801:Humans; D007037:Hypothyroidism / Q000000981:diagnostic imaging*; D021621:Imaging, Three-Dimensional; D011247:Pregnancy; D013960:Thyroid Function Tests; D016216:Ultrasonography, Prenatal / Q000379:methods*
D015415:Biomarkers