This is a Phase II, single-center (Cleveland Clinic), two-arm, randomized, parallel-group superiority trial. The two arms will compare IOUS-guided margin selection against standard macroscopic margin selection in patients undergoing ileocolic resection for terminal ileal Crohn's disease. Patients and outcome assessors (pathologists, endoscopists) will be blinded to the intervention arm, while surgeons, by the nature of the intervention, cannot be blinded. Randomization will be computer-generated with concealed allocation using permuted blocks to ensure balanced group sizes.