Measure optic nerve 3mm posterior to the globe/papilla, from inner wall to inner wall
Normal is <5mm
>6mm indicates elevated ICP
If grey zone range of 5-6mm may use presence of ultrasonographic papilledema to differentiate between normal or elevated ICP
U/S has a sensitivity of 95.6% and specificity of 92.3% for increased ICP
>6mm indicates elevated ICP
If grey zone range of 5-6mm may use presence of ultrasonographic papilledema to differentiate between normal or elevated ICP
Only perform if you can ensure that you do not put pressure on the globe
Findings
Decrease in size of globe
Anterior chamber collapse
Vitreous hemorrhage
Buckling of the sclera
Decrease in size of globe
Anterior chamber collapse
Vitreous hemorrhage
Buckling of the sclera
Bright, echogenic acoustic profile with associated shadowing or reverberation
Echogenic undulating membrane in the posterior globe, protruding into the vitreous
Evaluate with patient moving eye left/right
SN 97-100% and SP 83-100%
Retinal vs Vitreous Detachment Video (4 mins)
May be difficult to distinguish from a retinal detachment
May have a V-shaped appearance
Vitreous filled with multiple large echoes
Increasing the gain is helpful for detecting acute hemorrhages
Biconvex or round hyperechoic structure (lens) is displaced from its normal position.
With eye movement it may appear to move independently of surrounding structures.
Ocular ultrasound
Fundoscopic exam
Eye exam
Brain MRI
Eye antibiotics
Lumbar puncture
Canthotomy
Hydrocortisone topical