Patients , following a three-day low-fibre diet , received one of the two reduced preparations : @-L polyethylene glycol and four tablets of bisacodyl in association with @ mL of Iopamidol for faecal tagging administered on the same day as CTC examination ( group @ ) ; or a standard `` iodine-only '' preparation , consisting in @ ml of Iopamidol the day before the examination ( group @ ) .