Okay, the user wants me to translate "visual field defect" into Thai. Let me check if the term is already in Thai. No, it's in English. So I need to translate it.
First, "visual field" in medical terms is usually "สนามมองเห็น" in Thai. Then "defect" would be "ความบกพร่อง" or "ความผิดปกติ". Putting it together, "ความบกพร่องของสนามมองเห็น" seems accurate. Let me confirm if that's the standard term. Maybe check a medical dictionary or reliable source. Yes, that's correct. So the translation should be "ความบกพร่องของสนามมองเห็น".