Faculty Bibliography

INTRODUCTION/BACKGROUND:Occult spinal cord injury should be suspected based not only on the mechanism of trauma but also on the age of the patient. The pediatric spine has unique biomechanical and anatomical properties that must be considered carefully when evaluating spinal cord trauma. For instance, the hypermobility and elasticity of the spinal column in children often lead to self-reducing injuries that can mask spinal cord injury. CASE ILLUSTRATION/METHODS:We present the case of a 22-month-old male patient who was found to have ligamentous injury detected by magnetic resonance imaging (MRI) in the upper cervical spine but missed by MRI in the lower thoracic spine. Furthermore, there was no spinal cord injury in the upper cervical spine, but indeed a serious insult in the thoracic region. Since the advent of MRI, spinal cord injury without radiographic abnormality (SCIWORA) has become increasingly rare but not altogether extinct. CONCLUSIONS:We present a noteworthy example of the inadequacy of MRI in revealing SCIWORA, a term that is antiquated as we combine the latest imaging techniques with a better understanding of the biomechanics of trauma and spine injury. Based on the literature and our case illustration, we believe that the biomechanics of the pediatric spine must be considered when children who may have sustained a SCIWORA are examined.

OBJECTIVES/OBJECTIVE:Bilateral carotid artery occlusion associated with lymphocytic hypophysitis is exceedingly rare. We describe this association and review the literature. METHODS:The authors describe a 38-year-old woman with a history of severe headaches. Magnetic resonance (MR) imaging showed an intrasellar mass with invasion of both cavernous sinuses. Lymphocytic hypophysitis was diagnosed by transphenoidal biopsy. In the course of the disease, she developed symptoms of cerebral ischemia attributable to bilateral occlusion of her internal carotid arteries in both cavernous sinuses. She underwent bilateral superficial temporal artery-middle cerebral artery bypass surgery. RESULTS:The patient experienced progressive neurological recovery after surgery. A literature search revealed no other cases describing this unique association. CONCLUSIONS:Bilateral carotid artery occlusion may develop in the course of lymphocytic hypophysitis with cavernous sinus involvement. If indicated, cerebral revascularization should be performed to reverse cerebral ischemia.

Because skeletal dysplasias are primary disorders of bone, they have not been commonly understood as neurosurgical diseases. Nevertheless, neurosurgical complications are commonly encountered in many cases of dysplasia syndromes. The authors present two cases of skeletal dysplasia that caused overt instability of the cervical spine. One patient with a diagnosis of Gorham disease of the cervical spine was treated with prolonged fixation in a halo brace after an initial attempt at instrumentation with a posterior occiput--C4 fusion. The other patient, who at birth was identified to have camptomelic dysplasia, has been treated conservatively from the outset. Although these two patients presented with different disorders--in one patient adequate mature bone never formed and in the other patient progressive bone loss became apparent after a seemingly normal initial development--these cases demonstrate unequivocally that surgical options for fusion are ultimately limited by the quality of the underlying bone. In patients in whom the bone itself is inadequate for use as a substrate for fusion, there are currently limited treatment options. Future improvements in our understanding of chondrogenesis and ossification may lead to the design of superior methods of encouraging fusion in these patients; however, at the present time, long-term maintenance in a halo brace may, in fact, be the only treatment.

BACKGROUND:The optimal method to protect the brain from hemodynamic ischemia during carotid endarterectomy (CEA) remains controversial. This study reports our experience with induced arterial hypertension and selective etomidate cerebral protection in a cohort of patients who underwent CEA without shunting and continuous electroencephalography (EEG) monitoring. METHODS:We reviewed retrospectively 102 consecutive CEAs performed in 102 patients with routine EEG monitoring and general anesthesia between March 1998 and October 2002. There were 65 (66%) symptomatic and 37 (34%) asymptomatic individuals. A protocol of induced arterial hypertension against EEG ischemic changes during carotid artery cross clamping was followed. Only patients with EEG changes refractory to induced hypertension went into etomidate-induced burst suppression. RESULTS:EEG changes were classified as mild, moderate and severe. Twenty patients (19.6%) developed asymmetric EEG changes, of which the great majority were mild and moderate (75%, p< 0.05). Seven patients with moderate (n=3) and severe (n=4) EEG changes needed etomidate cerebral protection. There were no mortalities and only one stroke (0.98%) is reported in the series. The morbidity rate was 6.8% and included transient cranial nerve palsies (n=5) and wound hematoma (n=1). CONCLUSIONS:Carotid endarterectomy can be safely performed with EEG monitoring and selective induced arterial hypertension and etomidate cerebral protection. Our results suggest that this method may be a good alternative for shunting and its inherent risks.