This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Diseases of orbit, Lids and lacrimal apparatus, Subject name: Ophthalmology
A child with unilateral white reflex and raised intraocular pressure. the required investigation are all except 
Select and explain. 
A. Usg, B. Tonometer, C. Observation under anaesthesia, D. CT scan
D: CT scan
Answer: D: CT scan 
Explanation: In a child, a detailed retinal examination, tonometry, corneal diameter, gonioscopy, etc can only be done under anaesthesia Refer khurana 6/e