Because the eye is filled with vitreous which is very black on ultrasound, looking for abnormalities like retinal detachment is very simple. 2 minute video here
The optic nerve sheath has been shown to correlate with intracranial pressure. Measuring it is pretty straightforward. 4 minute video here.
Using ultrasound for central line placement IS standard of care. 5minsono video here.
The primary question for renal POCUS is that of hydronephrosis. It’s presence strongly points towards renal colic as the diagnosis in the appropriate patient. 2 minute video here.