Patients presenting with multiple cranial neuropathies are not uncommon in neurologic clinical practice. The evaluation of these patients can often be overwhelming due to the vast and complicated etiologies as well as the potential for devastating neurologic outcomes. Dysfunction of the cranial nerves can occur anywhere in their course from intrinsic brainstem dysfunction to their peripheral courses. The focus of this review will be on the extramedullary causes of multiple cranial neuropathies as discussion of the brainstem syndromes is more relevant when considering intrinsic disorders of the brainstem. The goals are to provide the reader with an overview of those extramedullary conditions that have a predilection for causing multiple cranial nerve palsies. In turn, this will serve to provide a practical and systematic approach to allow for a more targeted diagnostic evaluation of this, often cumbersome, presentation.

A 23‐year‐old, previously healthy, deployed U.S. soldier presented with bilateral temporal lobe seizures recalcitrant to multiple antiepileptic drugs and anti‐seizure anaesthetic agents. He received methylprednisolone, intravenous immunoglobulins, plasma exchange, and rituximab for presumed autoimmune encephalitis before achieving seizure freedom. Six weeks after presentation, the aetiology of his refractory seizures was found to be due to autoantibodies targeting the anti‐GABA(B)‐receptor. This case is noteworthy for being the first reported case of anti‐GABA(B)‐receptor limbic encephalitis presenting with new‐onset refractory status epilepticus (NORSE), a clinical syndrome that often carries a grave prognosis and in which a treatable aetiology is often never discovered. Our case also supports testing for GABA‐receptor autoantibodies and the upfront use of multi‐modal immunotherapy in patients presenting with limbic encephalitis and new refractory seizures.

High resolution peripheral nerve US is a useful modality in assessment of combat-related PNI. Muscle Nerve, 2016 Muscle Nerve 54: 1139-1144, 2016.