Keraring Intrastromal Segment Depth Measured by Spectral-Domain Optical Coherence Tomography in Eyes with Keratoconus

Table 2

Keraring measured and intended distance from the anterior and the posterior corneal surfaces.

Case	Eye	Intended distance; (μm)		Distance apex/; anterior surface (μm)		Distance inner corner/; posterior surface (μm)		Distance outer corner/; posterior surface (μm)
		Anterior surface	Posterior surface	Measured	Absolute difference	Measured	Absolute difference	Measured	Absolute difference
1	RE	391	136	205	186	98	38	225	89
2	LE	333	176	287	46	120	56	207	31
		335	199	313	22	146	53	210	11
3	LE	350	162	258	92	152	10	267	105
4	LE	370	147	306	64	119	28	328	181
5	RE	399	122	201	198	154	32	260	138
6	LE	377	125	216	161	157	32	266	141
7	RE	405	180	250	155	169	11	285	105
8	RE	400	100	302	98	98	2	198	98
	LE	358	118	343	15	101	17	239	121
9	RE	366	142	171	195	181	39	318	176
10	RE	344	118	167	177	143	25	285	167
	LE	357	121	215	142	154	33	260	139
11	RE	399	145	328	71	130	15	217	72
12	RE	400	152	303	117	173	21	314	162
	LE	401	160	198	203	176	16	359	199
13	RE	323	164	270	53	119	45	197	33
14	LE	356	125	255	101	126	1	251	126
	LE	354	190	321	33	190	0	245	55
15	LE	362	90	296	66	87	3	166	76
16	LE	360	156	349	11	145	11	172	16
17	RE	392	159	188	204	175	16	329	170
18	LE	383	120	318	65	98	22	142	22
19	RE	358	90	273	85	79	11	158	68
20	RE	387	120	251	136	156	36	289	169
21	RE	400	125	264	136	164	39	272	147
MEAN		371.54	140.08	263.38	108.92	138.85	23.54	248.42	108.35
SD		24.42	28.93	54.16	62.72	31.78	15.90	57.32	56.99
RANGE		323–405	90–199	167–349	11–204	79–190	0–56	142–359	11–199

RE: right eye. LE: left eye. Eyes with intrastromal tunnel created using femtosecond laser. SD: Standard Deviation.