Clinical relevance of cranial nerve injury following carotid endarterectomy

OBJECTIVES

The benefit of carotid endarterectomy (CEA) may be diminished by cranial nerve injury (CNI). Using a quality improvement registry, we aimed to identify the nerves affected, duration of symptoms (transient vs. persistent), and clinical predictors of CNI.

METHODS

We identified all patients undergoing CEA in the Vascular Study Group of New England (VSGNE) between 2003 and 2011. Surgeon-observed CNI rate was determined at discharge (postoperative CNI) and at follow-up to determine persistent CNI (CNIs that persisted at routine follow-up visit). Hierarchical multivariable model controlling for surgeon and hospital was used to assess independent predictors for postoperative CNI.

RESULTS

A total of 6,878 patients (33.8% symptomatic) were included for analyses. CNI rate at discharge was 5.6% (n = 382). Sixty patients (0.7%) had more than one nerve affected. The hypoglossal nerve was most frequently involved (n = 185, 2.7%), followed by the facial (n = 128, 1.9%), the vagus (n = 49, 0.7%), and the glossopharyngeal (n = 33, 0.5%) nerve. The vast majority of these CNIs were transient; only 47 patients (0.7%) had a persistent CNI at their follow-up visit (median 10.0 months, range 0.3-15.6 months). Patients with perioperative stroke (0.9%, n = 64) had significantly higher risk of CNI (n = 15, CNI risk 23.4%, p < .01). Predictors for CNI were urgent procedures (OR 1.6, 95% CI 1.2-2.1, p < .01), immediate re-exploration after closure under the same anesthetic (OR 2.0, 95% CI 1.3-3.0, p < .01), and return to the operating room for a neurologic event or bleeding (OR 2.3, 95% CI 1.4-3.8, p < .01), but not redo CEA (OR 1.0, 95% CI 0.5-1.9, p = .90) or prior cervical radiation (OR 0.9, 95% CI 0.3-2.5, p = .80).

CONCLUSIONS

As patients are currently selected in the VSGNE, persistent CNI after CEA is rare. While conditions of urgency and (sub)acute reintervention carried increased risk for postoperative CNI, a history of prior ipsilateral CEA or cervical radiation was not associated with increased CNI rate.

Recovery and rehabilitation after stroke

The incidence of stroke is about 1.5 to 2.5 per 1000 population per year. Stroke is among the commonest diagnoses on the list of yearly bed-days in Canadian hospitals. Recovery after stroke is often a lengthy and complex process in which doctors, nurses, therapists and family members are closely involved, yet little information is available about the use of therapy in stroke rehabilitation. This article discusses the mechanisms of recovery, the natural history of recovery of physical and social function, and the role of rehabilitation in treating acute stroke patients.

Identification of type C viruses by electron microscopy

The cores of a small proportion of the particles in purified preparations of type C viruses are characterized by two concentric shells that have a "double-ring" appearance in specimens prepared for electron microscopy by negative staining or thin sectioning techniques. This distinctive feature allows such particles to be recognized as viral in impure preparations. Detectability of double-ring particles is considerably enhanced by treating the specimens with a non-ionic detergent before fixation and negative staining. The limit of detectablity of type C virus (identified by the double-ring feature) in the presence of a large excess of nonviral particulates of similar size and density was assessed.