Endoscopic clip systems for hemostasis and defect closure in gastrointestinal endoscopy

Endoscopic clips are widely used for tissue approximation and hemostasis in gastrointestinal endoscopy. Since their introduction, significant technological advancements have expanded their functionality and versatility. Modern through-the-scope clips are now available in a range of designs with differences in open width, stem length, rotatability, opening/closing capabilities, and tensile strength - allowing tailored application depending on lesion size, location, and indication. Over-the-scope clips represent a more recent innovation, enabling robust, full-thickness closure of larger defects, ulcers, leaks, and fistulas. Mounted externally on the distal tip of the endoscope, Over-the-scope clips accommodate a fundamentally different and larger clip design compared to through-the-scope systems, allowing for deeper tissue capture and stronger compression. This review summarizes recent advances in endoscopic clipping, discusses device selection based on lesion characteristics and anatomical location, and provides practical technical tips. Emphasis is placed on the "anatomy" of clips, decision-making in clip choice, and optimal positioning techniques to maximize procedural success and safety in gastrointestinal defect closure and hemostasis.