TABLE 2.

Scheimpflug Densitometry Measuring Corneal Backscatter Before and After Trabeculectomy and in Healthy Age-Matched Controls

Layer	Preoperative		Postoperative		Healthy controls
	Annulus (mm)	GSU Mean ± SD	GSU Mean ± SD	P*	GSU Mean ± SD	P† to Preoperative Glaucoma	P‡ to Postoperative Glaucoma
AL; 0–120 μm	0–2	30.5 ± 8.2	26.7 ± 7.4	< 0.001	25.0 ± 2.3	0.003	0.299
	2–6	28.8 ± 7.9	24.9 ± 6.8	< 0.001	23.4 ± 2.1	0.003	0.318
	6–10	37.5 ± 10.2	33.9 ± 9.9	< 0.001	33.4 ± 9.1	0.119	0.844
CL	0–2	18.6 ± 4.4	18.2 ± 5.4	0.523	15.8 ± 1.2	0,005	0.045
	2–6	17.8 ± 3.8	17.2 ± 4.2	0.279	15.2 ± 1.2	0.003	0.033
	6–10	26.3 ± 6.8	24.9 ± 7.0	0.080	24.5 ± 6.3	0.307	0.823
PL; posterior 60 μm	0–2	13.8 ± 3.9	13.3 ± 4.6	0.289	12.6 ± 1.8	0.177	0.496
	2–6	13.8 ± 3.6	13.1 ± 3.9	0.075	12.8 ± 1.6	0.221	0.731
	6–10	21.6 ± 6.7	20.2 ± 6.9	0.020	21.8 ± 4.1	0.899	0.323
TL	0–2	21.0 ± 5.0	19.4 ± 5.5	0.010	17.8 ± 1.2	0.005	0.184
	2–6	20.1 ± 4.7	18.4 ± 4.8	0.004	17.1 ± 1.1	0.005	0.216
	6–10	28.5 ± 7.6	26.4 ± 7.7	0.011	26.6 ± 6.2	0.317	0.917
Entire cornea		25.5 ± 5.7	23.1 ± 5.8	0.001	22.8 ± 3.4	0.046	0.824

Bold type signifies P < 0.004.

^*P value: comparison between densitometry pre- and postoperative tested by linear mixed models.

^†P value: comparison between healthy controls and preoperative glaucoma patients, tested by independent t test.

^‡P value: comparison between healthy controls and postoperative glaucoma patients, tested by independent t test. Due to multiple testing, the P-value was adjusted by Bonferroni correction.