IS Case 434: Post-traumatic orbital pseudomeningocele

Matthew Thrall, MD

University of Rochester


Imaging Sciences URMC 2010
Publication Date: 2010-08-27

History

Patient is a 43-year-old male with increasing right-sided proptosis two weeks after severe motorcycle crash which resulted in polytrauma to the head, face, orbit, and body.

Findings

Right proptosis and low attenuation retrobulbar fluid collection.

Diagnosis

Post-traumatic orbital pseudomeningocele

Discussion

A pseudomeningocele is an abnormal collection of CSF that is encapsulated by soft tissues or other structures, but not dura mater (otherwise it is a meningocele). The three main causes are spinal surgery, brain surgery, and brachial plexus avulsion injury (tearing out the nerve root). Although described in case reports and written up in some textbooks, it is much less common to result from the orbitomaxillary trauma as it was here.

Orbital roof fractures are uncommon, and in a case study of 44 orbital roof fractures, a total of 6 were found to result in a pseudomeningoceles/meningoceles. The most common cause was road traffic accidents. As in this case, proptosis, exophthalmos, and ecchymoses are often present.

Diagnosis can be suspected when the Hounsfield units match that of CSF. In this case, confirmation was done with an sample of fluid being taken by ophthalmology and laboratory analysis confirming it was indeed CSF. Depending on the clinical situation, conservative management or neurosurgery can be performed.

References

  1. Upadhyay PK, Sinha SK. Case Report: Traumatic orbitomaxillary encephalocele. Indian Journal of Neurotrauma (IJNT) 2007; 4(2):127-128. http://ijntonline.com/Dec07/abs10.htm
  2. Grossman RI, Yousem D. Neuroradiology: the requisites, 2nd ed. Elsevier Inc., 2003:267-268

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