Unilateral Thalamic Lesions in Premature Infants: Risk Factors and Short-Term Prognosis

Abstract

The aim of the study was to assess incidence, risk factors, clinical symptomatology and short-term outcome of unilateral thalamic lesions in preterm infants, as detected by ultrasound. Sixteen preterm infants, born after a gestational age of less than 35 weeks, with a unilateral thalamic lesion, but without additional significant cerebral lesions, were included. Their follow-up data were compared to those of a selected control group consisting of healthy premature infants. In addition, the neonatal clinical data of the patients with a thalamic lesion were compared to data of the healthy control group and of a general control group, consisting of a non-selected year-cohort of preterm infants. During the study period, the incidence of unilateral thalamic lesions was 5.3% among preterm infants. Ultrasound was not able to distinguish between hemorrhagic and ischemic lesions. The infants with a unilateral thalamic lesion had a more complicated respiratory course and were ventilated significantly longer than infants without such a lesion. The infants with a thalamic lesion had disturbances in tone, persisting throughout infancy, while the healthy control group showed only transient disturbances in tone.

Cranial ultrasound findings in well newborn Ugandan infants

“…Unilateral thalamic densities have been described in apparently well term infants3 6 and in preterm infants,45 46 and have been seen in some infants associated with normal outcomes 4 6 45–47. In our current study all thalamic abnormalities were unilateral and focal; the mean 5 min Apgar score of these infants was 8, none appeared encephalopathic and they had a normal neurological examination 9.…”

Changes in echogenicity in the fetal brain: a prevalence study in fetuses at risk for preterm delivery

“…Localized BGTE were seen in 14.5% of the fetuses, being unilateral in half of them (6.5%). In high‐risk preterm neonates, unilateral BGTE were found in 5.3% of cases23, and were ascribed to hemorrhage or infarction in that region. We found not only unilateral, but in a substantial number of fetuses bilateral, localized BGTE.…”

Peri‐ and intraventricular cerebral sonography in second‐ and third‐trimester high‐risk fetuses: a comparison with neonatal ultrasound and relation to neurological development

“…Recently, unilateral thalamic echodensities were reported in 5.3% of preterm infants admitted to a tertiary neonatal unit21. The echodensities, which can be either ischemic or hemorrhagic in origin22–24, were related to disturbances in muscle tone during the first year of life21.…”