Hyperechoic foci in the thalamic region imaged via the posterior fontanelle: a potential mimic of thalamic pathology

Background. We have incidentally noted foci of increased thalamic echogenic ity (FITE) on cranial sonographic images obtained via the posterior fontane lle (PF) that were not confirmed on images obtained while scanning through the anterior fontanelle (AF), Therefore, we postulated that this is a norma l variant of PF imaging rather than true thalamic pathology. Objective. The purpose of this study was to determine the incidence of FITE detected on posterior and anterior fontanelle images. Materials ann methods. Parasagittal images were obtained bilaterally throug h the trigone of the lateral ventricles (including the thalami) via both th e anterior and posterior fontanelles in 15 consecutive neonates (30 thalami ) and evaluated in-dependently by two pediatric radiologists for the presen ce or absence of FITE, Thalami were graded as grade 0 (no FITE), grade 1 (p ossible FITE), or grade 2 (definite FITE), Follow-up CT (n = 3) and MR (II = 1)were reviewed. Results, FITE were absent in 87 % of thalami imaged via the AE and possible FITE were present in 13 % of these cases. No cases of definite FITE were i dentified via the AE However, possible FITE were identified in 33-40 % of t halami and definite FITE were seen in 33 % of thalami imaged via the PE Conclusions. FITE seen only on images obtained through the PF on cranial so nography are a normal finding and should not be attributed to thalamic hemo rrhage or ischemia.