Conception and design: Roth. Acquisition of data: Roth. Analysis and interpretation of data: Roth. Drafting the article: Roth. Critically revising the article: both authors. Reviewed submitted version of manuscript: both authors. Approved the final version of the manuscript on behalf of both authors: Roth. Statistical analysis: Roth. Administrative/technical/material support: Roth. Study supervision: Roth.
Portions of this study were presented orally at the International Federation of NeuroEndoscopy meeting, in Mumbai, December 8–11, 2013.