A subdural effusion is a collection of cerebrospinal fluid (CSF) trapped between the surface of the brain and the outer lining of the brain (the dura matter). If this fluid becomes infected, the condition is called a subdural empyema.
A subdural effusion is a rare complication of meningitis caused by bacteria. Subdural effusion is more common in infants.
Subdural effusion may also occur after head trauma.
Symptoms may include:
- Outward curving of a baby's soft spot (bulging fontanelle)
- Increased head circumference
- No energy (lethargy)
- Persistent fever
- Abnormally wide spaces in the bony joints of a baby's skull (separated sutures)
- Weakness or loss of movement on both sides of the body
Exams and Tests
The health care provider will perform a physical exam and ask about the symptoms.
To detect the subdural effusion, tests that may be done include:
- CT scan of the head
- Head size (circumference) measurements
- MRI scan of the head
- Ultrasound of the head
Surgery to drain the effusion is often necessary. Rarely, a permanent drainage device (shunt) is needed to drain fluid. Antibiotics may need to be given through a vein.
Treatment may include:
- Surgery to drain the effusion
- Drainage device, called a shunt, left in place for a short time or longer time
- Antibiotics given through a vein to treat the infection
Full recovery from a subdural effusion is expected. If nervous system problems continue, they are generally due to the meningitis, not the effusion. Long-term antibiotics is usually not needed.
Complications of surgery may include:
- Brain damage
When to Contact a Medical Professional
Call the provider if:
- Your child has recently been treated for meningitis and symptoms continue
- New symptoms develop
Heegaard WG, Biros MH. Head injury. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 8th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 41.
Kim KS. Bacterial meningitis beyond the neonatal period. In: Cherry JD, Harrison GJ, Kaplan SL, Steinbach WJ, Hotez PJ, eds. Feigin and Cherry's Textbook of Pediatric Infectious Diseases. 7th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 31.
Nath A. Meningitis. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 412.
Reviewed By: Amit M. Shelat, DO, FACP, Attending Neurologist and Assistant Professor of Clinical Neurology, SUNY Stony Brook, School of Medicine, Stony Brook, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.