C1-esterase Inhibitor (Cinryze) for Acute Treatment of Neuromyelitis Optica Exacerbation

The overall objective is to evaluate the tolerability/safety and preliminary efficacy of CINRYZE® (C1 esterase inhibitor \[human\]) as add-on therapy for treatment of acute optic neuritis and/or transverse myelitis in NMO and NMOSD. Primary Objective: To evaluate the safety and tolerability of 3-5 doses of 1000 - 2000 Units intravenous CINRYZE in NMO/NMOSD patients during an acute exacerbation. Secondary Objectives: * To determine the frequency of adverse events with CINRYZE in this patient population. * To determine the effect of CINRYZE on NMO clinical scores (Expanded Disability Status Scale and Low Contrast Visual Acuity). * To compare the change in MRI lesion size and extent following a course of CINRYZE.