Clinical Impact of Conventional Endosonography and Endoscopic Ultrasound-guided Fine-needle Aspiration in the Assessment of Patients with Barrett’s Esophagus and High-grade Dysplasia or Intramucosal Carcinoma who have been Referred for Endoscopic Ablation Therapy - Shami, V M; Villaverde, A; Stearns, L; Chi, K D; Kinney, T P; Rogers, G B; Dye, C E; Waxman, I (Endoscopy, 2006)