Fig 3 Quantification of papilloedema. Optic disc elevation: in ultrasound image, callipers measure from maximum disc height to lamina cribrosa; scatter plot shows means. Optic nerve diameter: in ultrasound image, callipers mark maximum pial diameter, short arrow indicates cross section through optic nerve, long arrow marks distended cerebrospinal fluid; scatter plot shows means. Retinal nerve fibre layer: in optical coherence tomogram image, arrow marks peripapillary distension; scatter plot shows means. P values are for changes from previous time point