Background and Study Aims: Detecting esophageal achalasia remains a challenge. We describe the diagnostic utility of corona appearance, a novel endoscopic finding specific to esophageal achalasia. Patients and Methods: Corona appearance and seven conventional endoscopic findings were compared for sensitivity and consistency (-value) among 53 untreated esophageal achalasia patients who underwent endoscopy at our hospital. The following criteria had to be met during lower esophageal sphincter examination using the attached ST Hood short-type for positive corona appearance: A) congestion inside the hood, B) ischemic change around the hood, and C) palisade vessels outside the hood. Results: Corona appearance had the highest sensitivity (91%; -value, 0.71). Other findings in descending order of sensitivity included 1) functional stenosis of the esophagogastric junction (EGJ; 86%; -value, 0.58), 2) mucosal thickening and whitish change (71%; -value, 0.27), 3) abnormal contraction of the esophageal body (59%; -value, 0.32), 4) dilation of the esophageal lumen (58%; -value, 0.53), 5) liquid remnant (57%; -value, 0.51), 6) Wrapping around EGJ (49%; -value, 0.14), and 7) food remnant (30%; -value, 0.88). Even in 22 patients with poor (grade 1) intraluminal expansion, corona appearance had highest sensitivity (88%) compared to other endoscopic findings (-value, 0.63). Conclusions: Among endoscopic findings using a ST Hood short-type to diagnose esophageal achalasia, corona appearance had the highest sensitivity and its consistency (-value) among endoscopists was substantial compared to other endoscopic findings. Similar results were obtained for esophageal achalasia cases with poor expansion. Endoscopic diagnosis of esophageal achalasia with hood attached is useful.