Table 2.

Optic nerve sheath diameter values for patients in groups 1–4

			ONSD
Group	Number	Clinical features	Range	Mean	SD
1	102	Normal	2.1–4.3 mm	3.1 mm	0.36
2	6	Hydrocephalus, normotensive	2.1–3.6 mm	2.9 mm	0.5
3	5	Hydrocephalus, symptoms of suggestive of raised ICP, not requiring intervention	2.6–3.8 mm	3.1 mm	0.4
4	12	Hydrocephalus, symptoms suggestive of raised ICP, requiring intervention	4.5–7.0 mm	5.9 mm	0.6