Lateral ventricular effacement as an isolated sonographic finding in premature infants: prevalence and significance

Optimal Timing of Spinal Ultrasound Evaluations for Sacral Dimples in Neonates: Earlier May Not Be Better

OBJECTIVES

A spinal ultrasound (US) evaluation during the immediate postnatal period may have limited ability in evaluating filum thickness because of the spinal cord pulsation caused by a crowded subarachnoid space and the cerebrospinal fluid deficiency during this period. This study aimed to determine the optimal timing of spinal US to evaluate sacral dimples in neonates.

METHODS

This study included 585 neonates who had a clinically suspicious sacral dimple and underwent spinal US examinations between January 2015 and August 2017. Patients were classified into 1 of 2 groups based on whether measurements of all parameters were possible (group A) or not (group B). Neonatal and maternal clinical factors, including the antenatal history and US parameters, were compared between groups.

RESULTS

Group A included 443 patients, and group B included 82. Patients in group B were significantly younger (6.2 versus 31.0 days), had a younger corrective age (38.9 versus 42.5 weeks), and had a smaller body weight (3.1 versus 4.6 kg) than those in group A (all P < .005). However, no statistically significant differences were found in other patient or maternal factors (P > .05 for all). The pulsation of the conus medullaris and nerve roots of the cauda equina (14.6% versus 100%), thickening and echogenicity of the filum terminale (2.4% versus 100%), and the presence of a normal subarachnoid space (18.3% versus 100%) were significantly more difficult to detect in group B than in group A (all P < .001).

CONCLUSIONS

For an accurate evaluation, which can reduce unnecessary confusion and costs, spinal US can be delayed until neonates grow beyond 31 days, with a corrected age of older than 42.5 weeks and body weight of greater than 4.6 kg.

Changes in the size of the lateral ventricles in the normal-term newborn following vaginal delivery

BACKGROUND

This is a study of the size of the lateral ventricles in a population of normal-term newborns following vaginal delivery.

OBJECTIVE

To assess the time course for the lateral ventricles to change from closed to open following vaginal delivery.

MATERIALS AND METHODS

A total of 143 normal-term newborns had a videotaped cranial ultrasound examination during the period from 1 to 156 h after birth. Many had from one to three additional examinations when returning for well-baby checks. Three methods [overlapping intervals (smoothed percentages), life table, and geometric distribution] were used to construct the approximate distributions of completely closed, partially open, and open ventricles.

RESULTS

Using smoothed percentages it was estimated that within 12 h of birth, 80% of newborns had closed lateral ventricles, 19% had partially open ventricles, and only 1% were completely open. The estimated median time from birth to partially open ventricles was in the period 36 to 60 h. The life table gave the estimated median time to partially open ventricles as 74 h. Fitting the data to a geometric distribution gave an estimated mean of 63 h.

CONCLUSION

The majority of normal newborns have closed lateral ventricles following vaginal delivery and these are partially opened by day 3 after birth.