OBJECTIVE: To evaluate the role of high frequency ultrasound of the spine in neonatal meningitis.
METHODS: Ultrasound of the neonatal spine was performed in 45 cases of meningitis in this study. Diagnosis of meningitis was confirmed by CSF examination. 57 controls and 41 subjects of proven sepsis were also enrolled. Ultrasound equipments used were Aloka prosound 3500 and Aloka α-10.(Aloka co.ltd.Japan) High frequency linear probes had a frequency range 6..67 to 13 MHz. Neonates were examined by a single observer who was blind to the laboratory reports. Longitudinal scans of the spine were obtained in prone and decubitus positions and appearances of the CSF and the subarachnoid trabeculae in the lumbar region were recorded. The posterior subarachnoid space was targeted for the study. Echogenic fluid and trabeculae were considered as a positive evidence of meningitis. RESULTS: The positive predictive value in meningitis was 79% whereas the negative predictive value was 82%. Specificity was 84%, while the sensitivity was 77%. 30 out of 41 sepsis subjects did not reveal any abnormal appearances on ultrasound while there were 11 false positives. CONCLUSION: The negative predictive value of ultrasound in meningitis was an encouraging finding of this study. This was the initial experience and with more exposure higher sensitivity and specificity can be expected.