Methods
This research complies with all relevant ethical regulations and was reviewed and approved by the Institutional Review Board (IRB protocol #: 2004P000198) at Beth Israel Deaconess Medical Center (BIDMC). Twenty-nine consecutively enrolled subjects, of which 15 were females and 14 were males, gave signed informed consent approved by the BIDMC IRB. The median age of subjects was 70 years (range 49–90 years). No compensation was provided for participating in the study.