Meningitis
Case Detail
| Anatomy: Brain |
Joseph Junewick, MD FACR |
| Diagnostic Category: Infectious-Inflammatory |
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| Created: over 3 years ago |
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| Updated: over 2 years ago |
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| Tags:
PEDS
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| Modality/Study Types:
US
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Activities: PDF ImageJA |
History
1 month old former premature infant with history of sepsis.
Case Images
Findings
US – Thickened, echogenic and hyperemic sulci.
Discussion
Meningitis results from bacteremia seeding the CNS by way of the choroid plexus giving rise to ventriculitis and then meningitis. Vasculitis of small and medium veins traversing the arachnoid space leads to thrombophlebitis and cortical infarctions.
Sonographic abnormalities are present in approximately 65% of infants with meningitis. Pia-arachnoid should not exceed 1.3 mm; sulci (2 layers of pia-arachnoid) should not exceed 2 mm. Vasodilation of pial vessels can be seen on color Doppler. Concave extra-axial collections sometimes containing low-level echoes can also be seen. Echogenic ependyma with low-level echoes in the in ventricular fluid; resolution of intraventricular debris is predicts efficacy of antibiotic selection. Parenchymal abnormalities include edema, infarction, and neuronal loss. Hydrocephalus can occur in the acute or chronic phase because of obstruction of CSF flow at the aqueduct of sylvius, outlet foramina or arachnoid granulations.
Reference
Yikilmaz A and Taylor GA. Sonographic Findings in Bacterial Meningitis in Neonates and Young Infants. Pediatric Radiol 2008; 38(2):129-137.



