Sonography in pyogenic meningitis

In this prospective study to evaluate usefulness of ultrasonography for early diagnosis and monitoring of complications of acute pyomeningitis, we performed serial sonographic examinations of skull in 50 infants (with open fontanelle) with proven pyomeningitis. One or more abnormal sonographic findings were detected in 32 infants. These were echogenic sulci (26%), ventriculomegaly with some or other complication (26%), brain abscess (20%), ventriculitis (14%), subdural effusion (6%) and cerebral edema (10%), and were detected mostly after the first week of illness. Ultrasonographic findings were in complete agreement with CT scan diagnosis of ventriculomegaly, ventriculitis, solitary brain abscess and cerebral edema. However, sonography missed cases of subdural effusion (2 out of 5), multiple brain abscesses (1 out of 2), and cerebral infarction (all the four), which were detected on CT Scan. Serial sonographic findings were useful in documenting progressive increase in ventricular size in all the 13 infants with ventriculomegaly and monitoring response to anti-edema therapy in 5 infants with cerebral edema. Sonography is a useful tool for diagnosis of complications of pyomeningitis after the first week of illness, and for monitoring the progress of ventriculomegaly.