Rotational Stability, Tilt and Decentration of a New IOL with a 7.0 mm Optic

Figures & data

Figure 1. Design of the Aspira-aXA intracoular lens

Figure 2. (a) Example of rotational stability evaluation performed with Photoshop. The reference axis is drawn by joining two critical details (e.g. Axenfeld-loops, limbal vessels) and the comparison axis is drawn by joining the IOL toric markings. (b) Example of tilt and decentration evaluation with customized Matlab code demonstrated with a raw image of Pentacam. For study data, a geometric distortion correction of the image was applied before data analysis

Table 1. Preoperative patient demographics; values are expressed as mean ± SD and median (range)

Parameter	Mean ± SD	Median (range)
Age (y)	70.17 ± 7.47	71.5 (55.0 to 87.0)
Gender, n (%) f/m	19 (45%)/23 (55%)
AL (mm)	23.63 ± 1.06	23.42 (21.78 to 26.59)
ACD (mm)	3.15 ± 0.37	3.17 (2.36 to 4.17)
CDVA (logMAR)	0.18 ± 0.21	0.10 (−0.10 to +1.00)
SE (D)	−0.30 ± 2.21	0.25 (−7.38 to +3.88)
IOL power (D)	21.66 ± 2.28	22.00 (16.50 to 25.00)
IOP (mmHg)	17.10 ± 2.90	17.00 (11.00 to 24.00)

AL: Axial length; ACD: Anterior chamber depth; SE: Spherical Equivalent; CDVA: corrected distance visual acuity; IOP: Intraocular pressure.

Table 2. IOL rotation at different follow-up stages to the entire study population

	EoS-1 D	1 D-1 W	1 W-1 M	1 M-4 M	EoS-4 M
N	52	59	57	52	47
Mean±SD	2.18 ± 2.23	0.91 ± 0.98	1.11 ± 1.27	0.80 ± 1.09	2.34 ± 2.39
Median	1.42	0.56	0.67	0.37	1.54
Min	0.00	0.00	0.00	0.03	0.00
Max	10.00	4.83	7.33	5.77	11.13
Direction	20/29/3	31/25/3	36/18/3	20/32/0	19/27/1

EoS = End of surgery; D = day; W = weeks; M = months.

Direction = clockwise/counterclockwise/none.

Figure 3. IOL rotational stability boxplot for all eyes from end of surgery (EoS) to each follow-up and in between follow-ups

Table 3. Mean (± SD) absolute tilt and decentration values for the right eyes (n = 24) and left eyes (n = 21)

IOL position	Side	1 week	1 month	4 months	p-value
Tilt (degree) Horizontal	Right eyes	1.19 ± 1.03	1.45 ± 1.42	1.36 ± 1.37	.45
	Left eyes	1.12 ± 0.75	1.02 ± 0.73	1.17 ± 0.81	.80
Vertical	Right eyes	1.50 ± 1.04	1.26 ± 0.68	1.57 ± 0.94	.33
	Left eyes	1.83 ± 1.26	1.23 ± 1.09	1.48 ± 0.89	.11
Decentration (mm) Horizontal	Right eyes	0.13 ± 0.10	0.13 ± 0.07	0.10 ± 0.07	.30
	Left eyes	0.09 ± 0.06	0.08 ± 0.08	0.09 ± 0.06	.94
Vertical	Right eyes	0.09 ± 0.06	0.10 ± 0.09	0.09 ± 0.07	.92
	Left eyes	0.14 ± 0.09	0.13 ± 0.11	0.14 ± 0.09	.83

Figure 4. (a) Decentration (mm) of all IOLs within the right (OD) and left (OS) eyes. (b) Tilt (degrees) of all IOLs within the right (OD) and left (OS) eyes

Data availability

The data used to support the findings of this study are available from the corresponding author upon request.