Imaging description

Meningoceles develop from herniation of the leptomeninges through an intervertebral foramen. They can be congenital or can be secondary to trauma or surgery. The lesions usually are 2–3 cm in size but can be considerably larger [1]. The diagnosis is made on CT with intrathecal contrast or MRI by demonstrating fluid attenuation of the mass and continuity of cerebrospinal fluid (CSF) from the thecal sac with the paraspinal lesion [1] (Figures 33.1 and 33.2). If the lesion is not fluid attenuation, it is indistinguishable from other neurogenic tumors on CT without intrathecal contrast. The paraspinal component is sharply marginated and can cause pressure erosions of adjacent bones. Enlargement of the intervertebral foramen is common [2]. Associated findings may include kyphoscoliosis with vertebral and rib anomalies [3].

Importance

Approximately two-thirds of cases are associated with neurofibromatosis [2]. The appearance and association with neurofibromatosis is very similar to neurofibromas.