The assessment of a swelling or mass of the wrist or the hand is commonly performed by radiologists. Because cysts on the wrist are, by far, the most frequent pathology. Diagnosis is usually based on standard radiography and ultrasound alone. Additional imaging techniques, and in particular MR imaging, are necessary to assess tumors, although malignant tumors of the hand are rare. Some benign cysts have pathognomonic characteristics visible on imaging. By understanding them, treatment planning may be improved.