Prospective Ocular Imaging for Intracranial Pressure Evaluation

Healthy controls: Inclusion Criteria: 1. Aged ≥18 years 2. Presumed normal ICP undergoing routine mydriatic ophthalmology OCT scans. Exclusion Criteria: 1. Significant media opacity restricting acquisition of retinal vein imaging and video capture in both eyes. 2. Current or previous evidence of glaucoma, glaucoma suspect, family history of glaucoma in a 1st degree relative, or non-glaucoma related optic neuropathy in both eyes. 3. Retinal vein or artery occlusions in both eyes (branch or central). 4. Active or history of proliferative diabetic retinopathy, or diabetic papillitis in both eyes. 5. Symptoms and/or signs that, in the opinion of the investigator, indicate possible raised intracranial pressure. 6. Current or previous history of disorders affecting intracranial pressure including, but not limited to, idiopathic intracranial hypertension, hydrocephalus, epilepsy, intracranial bleeds, space occupying lesions or tumours, traumatic brain injury, central nervous system inflammatory or infectious disorders, congenital neuro-cranial disorders, neurosurgical or interventional procedures. Radiologically-confirmed ischaemic stroke is permissible, provided the patient did not develop a subsequent haemorrhagic stroke or require neurosurgical intervention. 7. Current or recent (6 months) history of medication use affecting intracranial pressure including steroids, vitamin A analogues, tetracyclines, recombinant growth hormone, lithium, nitrofurantoin, nalidixic acid, sulfenazone, cyclosporine, amiodarone. 8. Bed-bound patients. 9. Patients who, in the opinion of the investigator, would be unwilling or unable to provide written informed consent, or undergo the testing procedures as described in the protocol. Patients due to undergo lumbar puncture or intracranial pressure bolt monitoring: Inclusion: 1. Aged ≥18 years. 2. Patients due to undergo lumbar puncture with measurement of Opening and Closing CSF pressures 3. Patients due to undergo continuous ICP monitoring Exclusion: 2\. Current or previous evidence of glaucoma or glaucoma suspect in both eyes. 3\. Retinal vein or artery occlusions in both eyes (branch or central). 4\. Bed-bound patients. 5\. Patients who, in the opinion of the investigator, would be unwilling or unable to provide written informed consent, or undergo the testing procedures as described in the protocol.