Table 1.

Comparison between Patients with and without Sheath Incision

	All Patients (n = 55)*		Preoperative Vision > PL−ve (n = 42)*
	Group A (Sheath Incised) (n = 33)	Group B (Sheath not Incised) (n = 22)	Group A (Sheath Incised) (n = 24)	Group B (Sheath not Incised) (n = 18)
PL−ve, no perception of light; PL+ve, perception of light.
Age (y): mean (range)	27.3 (6–52)	25 (6–45)	26.5 (6–52)	25.6 (6–45)
Preoperative visual acuity
• PL−ve	9	4	−	−
• PL+ve	4	2	4	2
• Hand movements	6	7	6	7
• 1/60	6	3	6	3
• 2/60	2	1	2	1
• 3/60	1	3	1	3
• 6/60	5	2	5	2
Fracture (optic canal/postorbit)
• Fracture present	12	10	6	6
• No Fracture	21	12	18	12
Grade of Injury†
• Grade 2 (no fracture, vision > PL−ve & ≤ 6/60)	14	8	14	8
• Grade 3 (fracture or PL−ve)	11	7	8	7
• Grade 4 (fracture & PL−ve)	8	7	2	3
Injury-operation interval (d)
Median	63	61	67	66.5

^*Two cases excluded from initial data set of 57 because of inadequate length of follow up.

^†Grade of injury is based on fractures of the optic canal or posterior orbit and the worst recorded vision.