Clinical features

Look for 

• papilloedema ^d
• absence of retinal vein pulsation ^c

 Why?

Retinal vein pulsation makes raised intracranial pressure unlikely

Patient	Target Disorder and Reference Standard	Diagnostic Test	LR+ (95% CI)	Post-test Probability	LR- (95% CI)	Post-test Probability
suspected raised intracranial pressure c (pre-test probability: 23%)	raised intracranial pressure (lumbar puncture or follow-up)	absence of retinal vein pulsation	8.1 (5.3 to 13)	70%	0.0 (0.0 to 0.077)	0%