Background/Aims: Colorectal polyp detection during colonoscopy is influenced by the lesion location, size, morphology, and histology. However, no studies have systematically assessed the difficulty of detection along the short axis of the intestinal lumen. This study aimed to evaluate the colorectal polyp detection rates on this axis during colonoscopy. Methods: This retrospective study analyzed 1,169 polyps in 513 patients who underwent colonoscopy at Showa University Hospital between November 2022 and February 2023. The short-axis lumen was divided into: upper right, lower right, lower left, and upper left. Each polyp detected was assigned to a quadrant. Detection rates were compared across quadrants and analyzed for associations with clinicopathological factors including lesion size, location, macroscopic type, and examiner experience. Results: The lesion detection rates varied significantly by quadrant. The upper left quadrant had the lowest detection rate (17.5%) compared with the expected 25.0% per quadrant. Subgroup analyses consistently confirmed the lower detection rates in this quadrant across most lesion types and patient groups, except for lesions in the cecum and rectum. Conclusions The lower detection rate in the upper left quadrant suggests that this orientation poses a challenge and may increase the number of missed lesions. Enhanced examination of this area may improve detection; however, further prospective studies are required.

No abstract available.
Dermatitis* ; Epinephrine* ; Eyelids*

Unroofed coronary sinus (URCS) is a rare cardiac anomaly, in which communication occurs between the coronary sinus (CS) and the left atrium (LA) because of partial or complete absence of the CS roof. A 30-year-old woman was scheduled for surgical closure of atrial septal defect, mitral valve repair and tricuspid annuloplasty. The intraoperative transesophageal echocardiography (TEE) revealed left-to-right shunt between the CS and the LA. The three-dimensional (3D) TEE confirmed the diagnosis of partially URCS. This defect was repaired with a pericardial patch. In this case, the 3D images of URCS, which were a helpful supplement to the 2D images, providing better visualization of the wall defect and more information regarding the size and location of the defect. The combined use of 2D and 3D images provides valuable information to aid in understanding the anatomy and morphology of this rare anomaly.
Adult ; Coronary Sinus* ; Diagnosis ; Echocardiography, Three-Dimensional ; Echocardiography, Transesophageal* ; Female ; Heart Atria ; Heart Defects, Congenital ; Heart Septal Defects, Atrial ; Humans ; Mitral Valve ; Vena Cava, Superior*