Objective and importance: Four patients with craniovertebral junction anomalies (CVJ) and Klippel-Feil cervical fusion defects associated with dermoid and epidermoid cysts are described.
Clinical presentation: During the 10-year period from 1994 until May 2004, 435 patients with developmental CVJ anomalies presented to our institution. Four of these patients harbored a constellation of CVJ anomalies with dermoid and epidermoid cysts (hospital prevalence, 0.9%). All patients (ages 18, 23, and 25 yr) presented with features of spastic quadriparesis, restriction of neck movements, and raised intracranial pressure. Magnetic resonance imaging showed features of CVJ anomalies in all patients (occipitalization of C1, 3 patients; basilar invagination, 3 patients; atlantoaxial dislocation, 4 patients; and an abnormal posteriorly pointed dens, 1 patient), along with a Klippel-Feil anomaly (Patients 1-3, 2nd and 3rd cervical vertebrae). Patient 4 also had a Chiari malformation with syrinx. In addition, all four patients had coexisting dermoid or epidermoid cysts (Patients 1 and 3, midline posterior fossa epidermoid; Patient 2, midline posterior fossa dermoid; Patient 4, quadrigeminal cistern epidermoid).
Intervention: Patients 1 and 2 underwent a posterior midline approach, excision of the tumor, and an occipitocervical fusion (the atlantoaxial dislocation was reducible). Patient 3 underwent transoral excision of the odontoid, followed by tumor excision and occipitocervical fusion via the posterior route. These patients had uneventful recovery. Patient 4 did not undergo an operation.
Conclusion: Association of CVJ anomalies with Klippel-Feil and dermoid and epidermoid cysts is extremely rare, with only two previously reported cases. The patient who presented with a quadrigeminal cistern epidermoid with a craniovertebral junction anomaly and Chiari malformation with syrinx is the first such case ever reported in the literature. Apart from therapeutic implications, these patients may shed new light on the embryogenesis. Furthermore, the gathering of these manifestations may constitute components of a new syndrome that has gone unnoticed until now.