Table 3

Details of orthoptic findings

Patient		Prism cover test with scleral lens			Prism fusion range with scleral lens		4 Dioptre base-out prism		Previous ophthalmic history
Patient		6 metres (prism dioptres)			1/3 metre (prism dioptres)		4 Dioptre base-out prism		Previous ophthalmic history	6 metres (prism dioptres)	1/3 metre (prism dioptres)
1	1XT	1R/L	4XT	1R/L	10 PBO–4 PBI	40 PBO–4 PBI	Not overcome	Patched
2	4XT		16XT		4 PBO–6 PBI	16 PBO–14 PBI	Not overcome	None
3	12XT		8XT		NIL	NIL	Not overcome	None
4	2XT		8XT		12 PBO–2 PBI	25 PBO–8 PBI	Not overcome	None
5	16XT	2L/R	16XT	2L/R	6 PBO–2 PBI	6 PBO–2 PBI	Not overcome	None
6	1XT	1L/R	4XT	1L/R	NIL	18 PBO–8 PBI	Not overcome	PK
7	4XT	2R/L	10XT		6 PBO–1 PBI	6 PBO–1 PBI	Not overcome	None
8	4XT	2R/L	6XT		16 PBO–6 PBI	35 PBO–10 PBI	Not overcome	None
9	2XT	2L/R	8XT	2L/R	10 PBO–8 PBI	20 PBO–16 PBI	Not overcome	PK
10	1XT		4XT		16 PBO–8 PBI	35 PBO–10 PBI	Not overcome	None
11	2ET	1R/L	4XT	1R/L	20 PBO–2 PBI	45 PBO–16 PBI	Not overcome	None
12	6XT		16XT		NIL	NIL	Not binocular	None
13	1ET	2L/R	2XT	3L/R	16 PBO–4 PBI	30 PBO–14 PBI	Not overcome	None
14	1XT		1XT		20 PBO–8 PBI	40 PBO–16 PBI	Not overcome	None
15	0	4R/L	6XT	2R/L	16 PBO–6 PBI	30 PBO–14 PBI	Not overcome	None
16	6XT		4XT		NIL	NIL	Not binocular	None
17	2XT	1R/L	8XT	2R/L	6 PBO–6 PBI	25 PBO–14 PBI	Not overcome	None
18	20XT	6R/L	4XT	2R/L	20 PBO–10 PBI	20 PBO–12 PBI	Not overcome	None
19	0	1L/R	6XT	2L/R	12 PBO–4 PBI	30 PBO–10 PBI	Not overcome	None
20	1XT		10XT		2 PBO–4 PBI	4 PBO–4 PBI	Not overcome	None

XT = exodeviation; ET = esodeviation; PBO = prism base out; PBI = prism base in; PK = penetrating keratoplasty to fellow eye; R/L = right over left; L/R = left over right.