A 75 year old lady with Alzheimer’s disease is brought in by her concerned daughter to see you. She says her mother is complaining of a headache and feeling sickly since yesterday evening. She has vomited twice and it is difficult to get any other history other than her nodding that her right eye hurts. She is known to have chronic lower back pain and Hypothyroidism. Drug history includes Codeine, Ibuprofen and Levothyroxine. She is eating as normal and maintaining her oral intake.
The patient does not cooperate with your initial attempt to examine her eyes, but you note from initial glance that her right cornea is hazy.
What is the most likely diagnosis?