Intracerebral pneumocephalus and hemiparesis as a complication of a halo vest in a patient with multiple myeloma. Case report.

A halo orthosis is often used to immobilize the cervical spine after severe injury in patients who cannot tolerate surgery. Although complications such as pin loosening or brain abscess have been reported, there are no reported cases of hemiparesis following pneumocephalus associated with halo use. The authors report the case of a 77-year-old man with multiple myeloma who, after undergoing halo vest therapy and chemotherapy, suddenly developed hemiparesis and speech disturbance. Diagnostic neuroimaging demonstrated penetration of the inner table at the right posterior pin site and intracerebral pneumocephalus at the parietal lobe. Intraoperative inspection revealed only air and no purulent materials or cerebrospinal fluid in the cystic lesion. When a halo device is used, attention to detail in pin application, maintenance, and proper pin-site care must be undertaken to minimize complications. The tightening of the pin in cases in which late-onset loosening has occurred should not be performed. Additionally, because late loosening of the pin and pin-site infection increase the risks of complications, a halo vest should be used only as a short-term treatment, and the clinician should be aware of the possible increased risk of serious complications such as pneumocephalus or subdural abscess formation.