gms | German Medical Science

Objective: Osteopetrosis (“marble bone disease”) is a heterogeneous group of rare, inherited disorders of the skeleton due to deficient osteoclastic resorption of the primary spongiosa. The major neurological effects result from the restriction of growth of foramina through which the cranial nerves, spinal cord and major blood vessels traverse the scull. Therefore patients develop cranial nerve palsies. The specific cranial and intracranial manifestations reflect the varying calvarial and skull base thickening. Neurosurgical management of increased intracranial pressure or cranial nerve compression is often required. We present a case of Chiari-I-malformation due to osteopetrosis associated with hydrocephalus and the respective surgical management.

Methods: 10-year old boy from Sudan with genetically not determined osteopetrosis and Chiari-I-malformation admitted for craniocervical decompression. He suffered from headaches 3-4 times a week especially after sleeping, balance problems and recurrent pathological bone fractures. The examination revealed macrocephaly, midfacial hypoplasia, poor visual acuity due to optical neuropathy, papilledema, VII palsy on the right side, hearing loss, gait disturbance. No sensory or motor deficits, deep tendon reflexes normal. MRI head and spine: Chiari-I-malformation with a 13 mm decent of cerebellar tonsils and syringohydromyely C2-Th8, brain atrophy, disturbed CSF circulation, thickened skull bone. Large enough posterior fossa decompression with C1 laminectomy and duraplasty under SSEP and MEP monitoring was performed uneventfully. The bone was grossly abnormal. Intraoperative ultrasonography showed a pulsation and motion of the tonsillar tips. After surgery the patient still had severe headache and nausea, MRI showed signs of perturbed CSF circulation, a persisting hydrocephalus and CSF collection over the craniectomy. 3^rd ventriculostomy was planed but could not be performed because of severe coagulopathy. Hematologic work up showed an altered aggregation of the platelets and factor XIII-deficiency, not visible in normal blood work. Consequently the patient got a VP-shunt with padi-9/24-valve, preoperatively he received 4µg desmopression and 500 IE factor XIII. Additionally 4x250 mg tranexam acid was given until the end of wound healing.

Results: The boy could be discharged in good clinical condition, without headache or nausea, gait improved during hospital stay.

Conclusion: Osteopetrosis is a rare disease, which can cause a symptomatic Chiari-I malformation and hydrocephalus that require neurosurgical treatment.