This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Contrast Agents, Subject name: Radiology
[{'content': 'Which is Less nephrotoxic? \nSelect and explain. \nA. Iodixanol, B. Diatrizoate, C. Metrizoate, D. Ioxaglate', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Contrast Agents with High Iodine:paicle ratio tends to be less nephrotoxic Iodixanol is Isoosmolar contrast agent , Nonionic Dimer with Iodine :Paicle Ratio of 6:1 and tends to be less nephrotoxic than the other iodinated compounds given here Contrast-induced nephropathy (CIN) Classically defined as a serum creatinine increase of at least 25% or an absolute increase in serum creatinine of 0.5mg/dL after using iodine contrast agent without another clear cause for acute kidney injury within 48-72hrs of Intravenous contrast Markers of CIN Serum Cystatin C levels Neutrophil Gelatinase associated lipocalcin(NAGL) eGFR<60ml/min For prevention- Maintain Hydration', 'role': 'assistant'}]