General Spine

Shehanaz, Ellika, MD, DM
Shehanaz, K, Ellika, MD, Non ASSR Member
Horia, Marin, MD, Non ASSR Member
Mitchell, Pace, MD, Non ASSR Member
Suresh, Patel, MD, Non ASSR Member
Muwaffak, Abdulhak, MD, Non ASSR Member

Poster

Purpose

Pseudomeningocels are uncommon causes of myelopathy. Clinical presentation is usually insidious related to mass effect on the spinal cord or adjacent nerve roots, or can be related to associated hemosiderosis. Surgical treatment involves relief of the mass effect through fenestration or resection, and obliteration of the communication with the thecal sac. Given that the pseudomeningoceles usually extend over multiple levels, appropriate identification of the dural breach can be challenging. We would like to present our experience with five cases of thoracic pseudomeningocoeles diagnosed and treated at our institution.

Methods & Materials

In this exhibit we will review five cases of thoracic pseudomeningocoeles who underwent myelography, dynamic CT myelography and MRI. We will point out the diagnostic contributions made by dynamic CT myelogram and also discuss the association of thoracic pseudomeningocoeles with superficial siderosis of the CNS. We will describe the protocol at our institution for dynamic CT myelograms. The clinical presentation and treatment options are also reviewed.

Results

Dural defects with extra-arachnoid fluid collections are frequent, though unrecognized finding in superficial siderosis of the central nervous system.
In the presence of long segment extra-arachnoid intraspinal collection, a dynamic CT myelogram may be required to identify the exact defect site. Dynamic CT myelogram in each of our cases showed filling of the extra-arachnoid fluid collection with contrast, confirming communication with the subarachnoid space. The dynamic nature of the study helped in identifying progressive differential opacification of the ventral cyst leading to localization of the site of communication between the fluid collection and thecal sac.

Conclusion

Pseudomeningocoeles are well described and well know entities, but the association with superficial siderosis is not well recognized. Our exhibit illustrates the importance of looking for a communication of the extra-arachnoid fluid collection with the subarachnoid space with dynamic CT myelogram for identification of the precise site of the fistulous communication for surgical correction. However we do not advocate using this technique for all patients with a leak, as it is more invasive, has a higher radiation dose and is more time and resource intensive.