A One Year Longitudinal Comparative Analysis of Visual Outcomes Between Femtosecond Laser-Assisted Cataract Surgery and Standard Phacoemulsification Cataract Surgery

Figures & data

Table 1 Baseline Demographics

	PCS (%) N = 155	FLACS (%) N = 143	P value
Patient Demographics
Age at surgery (years)	66 ± 9[37–86]	68 ± 9 [41–89]	0.03
≤70 yrs old at surgery	100 (64.5)	79 (55.2)	0.12
Male	60 (38.7)	66 (46.2)	0.20
Female	95 (61.3)	77 (53.8)
Right eye	73 (47.1)	66 (46.2)	0.91
Left eye	82 (52.9)	77 (53.8)
Diabetes Mellitus	20 (12.9)	19 (13.3)	1.00
Hypertension	39 (25.2)	30 (21.0)	0.41
Preoperative characteristics
Axial Length (mm)	24.22 ± 1.40 [21.34–27.87]	24.30 ± 1.26 [21.34–28.82]	0.24
Aqueous Depth (mm)	2.73 ± 0.36 [1.94–3.59]	2.72 ± 0.40 [1.80–4.73]	0.94
Km (D)	44.08 ± 1.77 [38.81–47.9]	44.24 ± 1.50 [39.82–47.92]	0.44
Lens Thickness (mm)	4.47 ± 0.45 [3.23–5.33]	4.51 ± 0.39 [3.19–5.41]	0.60
White-to-White (mm)	12.03 ± 0.46 [10.81–13.54]	12.11 ± 0.40 [11.10–13.21]	0.06
Central Corneal Thickness (µm)	543 ± 37 [436–658]	5467 ± 37 [463–625]	0.58
IOP (mmHg)	14.1 ± 3.5 [6.0–24.0]	14.4 ± 3.4 [7.0–24.0]	0.98
Spherical Equivalent (D)	−2.10 ± 3.71 [−18.38–5.50]	−1.86 ± 3.60 [−17.88–5.13]	0.72
Myope (MRSE <0)	102 (65.8)	91 (63.6)	0.81
Hyperope (MRSE >0)	49 (31.6)	43 (30.1)	0.90
UNVA (logMAR)	0.42 ± 0.23 [0–0.70]	0.45 ± 0.24 [0–1.10]	0.41
BCVA (logMAR)	0.17 ± 0.16 [−0.12–0.70]	0.16 ± 0.18 [0–1.10]	0.16
UDVA (logMAR)	0.65 ± 0.40 [0–1.40]	0.70 ± 0.44 [0–1.48]	0.25
Refractive Cylinder	−1.16 ± 0.97 [−5.75–0.5]	−1.28 ± 1.05 [−6.25–0.1]	0.31
Preoperative astigmatism (D)	1.69 ± 1.06	1.79 ± 0.53	0.08
Postoperative Astigmatism & Cylinder
Postoperative astigmatism (D)	0.58 ± 0.55	0.56 ± 0.36	0.42
1 week postoperative Refractive Cylinder	−0.55 ± 0.97 [−5.75–0.5]	−0.59 ± 0.53 [−2.25–2.25]	0.72
3 months postoperative Refractive Cylinder	−0.55 ± 0.51 [−2.75–0.5]	−0.59 ± 0.78 [−5.25–1.25]	0.76
1 year postoperative Refractive Cylinder	−0.56 ± 0.38 [−1.5–0]	−0.59 ± 0.37 [−1.25–0.5]	0.80
Operative planning:
IOL power (D)	19.00 ± 4.07 [6.00–28.00]	18.59 ± 4.50 [5.00–29.00]	0.21
Toric IOL	60 (38.7)	70 (49.0)	0.08
Non-Toric IOL	91 (58.7)	73 (51.0)	0.20
Monofocal IOL	55 (35.5)	47 (32.9)	0.71
LAL	2 (1.3)	3 (2.1)	0.67
MX60	20 (12.9)	17 (11.9)	0.86
ZCB00	26 (16.8)	22 (15.4)	0.87
ZA	0 (0.0)	2 (1.4)	0.23
SA/SN60WF	5 (3.2)	3 (2.1)	0.72
Toric Monofocal IOL	21 (13.5)	29 (20.3)	0.12
ZCT/ZCU	21 (13.5)	26 (18.2)	0.27
MXUT	0 (0.0)	3 (2.1)	0.11
Multifocal IOL	36 (23.2)	26 (18.2)	0.32
TFAT00	28 (18.1)	24 (16.8)	0.88
ZXR00	5 (3.2)	2 (1.4)	0.45
ZMA00	1 (0.6)	0 (0.0)	1.00
Multifocal Toric IOL	39 (25.2)	41 (26.3)	0.43
ZXT	30 (19.4)	29 (20.3)	0.88
ZKU	0 (0.0)	3 (2.1)	0.11
TFAT#	8 (5.2)	9 (6.3)	0.80

Notes: Data presented as mean ± standard deviation [range] or number (%). Bold signifies statistically significant; P < 0.05.

Abbreviations: BDVA, best distance visual acuity; FLACS, femtosecond laser-assisted cataract surgery; IOL, intraocular lens; IOP, intraocular pressure; LAL, RxSight, light adjustable lens; logMAR, logarithm of the minimum angle of resolution; mmHg, millimeters of mercury; MRSE, manifest refraction spherical equivalence; MX60, B&L enVista Monofocal IOL; MXUT, B&L enVista Toric Monofocal IOL; PCS, phacoemulsification cataract surgery; SA/SN60WF, Alcon AcrySof IQ IOL; TFAT00, Alcon PanOptix Multifocal IOL; TFAT#, Alcon PanOptix Multifocal IOL; UDVA, uncorrected distance visual acuity; UNVA, uncorrected near visual acuity; ZCB00, Johnson&Johnson TECNIS Monofocal 1-Piece IOL; ZA, Johnson&Johnson TECNIS Monofocal 3-piece IOL; ZCT/ZCU, Johnson&Johnson TECNIS Toric II IOL; ZKU, Johnson&Johnson TECNIS Multifocal Toric II IOL; ZMA, Johnson&Johnson TECNIS Multifocal IOL; ZXR00, Johnson&Johnson TECNIS Symfony IOL; ZXT, AMO Symfony Toric IOL.

Table 2 Postoperative Mean UDVA (logMAR)

		Sample Size (PCS/FLACS)	PCS	FLACS	P value
Mean UDVA	1 week	120/119	0.15 ± 0.16	0.14 ± 0.18	0.34
	3 months	53/60	0.15 ± 0.17	0.15 ± 0.18	0.94
	1 year	22/28	0.19 ± 0.14	0.12 ± 0.12	0.09
Mean BDVA	1 week	66/56	0.03 ± 0.07	0.03 ± 0.07	0.58
	3 months	52/56	0.02 ± 0.06	0.007 ± 0.05	0.78
	1 year	24/30	0.02 ± 0.06	0.005 ± 0.05	0.48
Mean UNVA	1 week	55/62	0.25 ± 0.18	0.26 ± 0.18	0.72
	3 months	32/39	0.22 ± 0.19	0.21 ± 0.18	1.00
	1 year	20/24	0.27 ± 0.24	0.31 ± 0.25	0.54

Notes: Data presented as mean ± standard deviation, PCS/FLACS, or number. P-value < 0.05 is considered statistically significant.

Abbreviations: BDVA, best distance visual acuity; FLACS, femtosecond laser-assisted cataract surgery; logMAR, logarithm of the minimum angle of resolution; PCS, phacoemulsification cataract surgery; UDVA, uncorrected distance visual acuity; UNVA, uncorrected near visual acuity.

Figure 1 Patients 20/20 or better and 20/40 or better at 1 week, 3 months, and 1 year postoperatively. (A and B) Uncorrected distance visual acuity (UDVA) of 20/20 or better and 20/40 or better for PCS (A) and FLACS (B) patients preoperatively, 1 week, 3 months, and 1 year. Patients with target refractions not set to 0 D were removed. C-D: Best distance visual acuity (BDVA) of 20/20 or better and 20/40 or better for PCS (C) and FLACS (D) patients preoperatively, 1 week, 3 months, and 1 year. E-F: Uncorrected near visual acuity (UNVA) of 20/20 or better and 20/40 or better for PCS (E) and FLACS (F) patients preoperatively, 1 week, 3 months, and 1 year. All patients receiving monovision were excluded.

Table 3 Odds Ratio of UDVA

		PCS:FLACS OR (95% CI) 20/20 or Better	P value	PCS:FLACS OR (95% CI) 20/40 or Better	P value
UDVA	1 week	0.99 (0.55–1.76)	1.00	0.76 (0.29–1.95)	0.63
	3 months	1.53 (0.85–2.75)	0.23	0.35 (0.12–1.01)	0.08
	1 year	0.21 (0.10–0.42)	0.0001	0.37 (0.11–1.31)	0.37
BDVA	1 week	1.27 (0.67–2.44)	0.50	*	1.00
	3 months	1.23 (0.56–2.69)	0.69	*	1.00
	1 year	0.58 (0.28–1.24)	0.19	*	1.00
UNVA	1 week	0.22 (0.07–0.72)	0.02	0.63 (0.32–1.25)	0.30
	3 months	0.63 (0.33–1.19)	0.26	1.23 (0.64–2.36)	0.74
	1 year	1.29 (0.69–2.40)	0.53	1.40 (0.78–2.52)	0.37

Notes: Data presented as number (lower 95% confidence interval–upper 95% confidence interval). *All patients were 20/40 or better, no odds ratio available. Bold p-value signifies statistically significant; P < 0.05.

Abbreviations: BDVA, best distance visual acuity; CI, confidence interval; FLACS, femtosecond laser-assisted cataract surgery; PCS, phacoemulsification cataract surgery; UDVA, uncorrected distance visual acuity; UNVA, uncorrected near visual acuity.

Figure 2 Percentage of patients with BDVA and UDVA of specific visual acuity at 3 months postoperative. (A) Comparison of PCS patients with preoperative BDVA and postoperative UDVA showing the percentage of patients presenting with 20/x visual acuity. All patients with target refractions not set to 0 D were removed from UDVA. (B) Comparison of FLACS patients with preoperative BDVA and postoperative UDVA showing the percentage of patients presenting with 20/x visual acuity. All patients' target refractions not set to 0 D were removed from UDVA.

Figure 3 Comparison of Visual Outcomes including Safety, Stability, and Predictability. Comparison of visual acuity in 3 months postoperative UDVA with preoperative BDVA (A). All patients with target refractions not set to 0 D were removed from UDVA. Comparison of postoperative BDVA change in PCS versus FLACS patients (B). Comparison of spherical equivalent refraction accuracy in PCS versus FLACS patients at 3 months postoperative organized by accuracy to the intended target (C). Comparison of stability of spherical refraction in PCS versus FLACS patients at 3 months postoperative (D).

Figure 4 Astigmatic comparison. (A and B) Comparison of pre- and postoperative (3 months) refractive astigmatism in PCS patients (A) and FLACS patients (B). (C) Plot of target versus actual astigmatism in PCS versus FLACS patients at 3 months postoperatively. (D) Comparison of the astigmatic angle of error in PCS versus FLACS patients at 3 months postoperative.

Figure 5 Postoperative Refractive Astigmatism. Pre- and postoperative comparison of refractive astigmatism with the percentage of eyes in PCS (A) and FLACS (B).

Figure 6 Vector Analysis and Prediction Error of Postoperative Refractive Astigmatism. Comparison of mean pre- and postoperative astigmatism in patients undergoing PCS (A) and FLACS (B) showing 95% confidence ellipse of dataset and centroid with an N value of 31. Comparison of postoperative refractive astigmatism prediction error in PCS and FLACS patients (C).

Table 4 Postoperative Patient Complaints and Complications

	PCS	FLACS	P value	PCS:FLACS OR (95% CI)
Preoperative	N = 155	N = 143
Glare	77 (49.7)	76 (53.1)	0.56	0.87 (0.55–1.37)
Halo	20 (12.9)	22 (15.4)	0.62	0.81 (0.42–1.57)
Photophobia	17 (11.0)	6 (4.2)	0.03	2.81 (1.08–7.35)
Dry eyes	22 (14.2)	22 (15.4)	0.87	0.91 (0.48–1.73)
Night vision issues	71 (45.8)	66 (46.2)	1.00	0.99 (0.63–1.56)
3 months postoperative	N = 65	N=68		0.35
Glare	0	1 (1.5)	0.48	–
Halo	3 (4.6)	8 (11.8)	0.13	0.33 (0.09–1.28)
Photophobia	2 (3.1)	0	0.50
Dry eyes	6 (9.2)	13 (19.1)	0.09	0.40 (0.15–1.09)
Night vision issues	6 (9.2)	3 (4.4)	0.50	1.88 (0.46–7.66)
1 year postoperative	N = 27	N = 33		0.25
Glare	0	0	1.00	–
Halo	0	0	1.00	–
Photophobia	0	0	1.00	–
Dry eyes	5 (18.5)	11 (33.3)	0.12	0.40 (0.14–1.18)
Night vision issues	0	0	1.00	–
Postoperative procedures
YAG laser capsulotomy (≤ 3 months post-op)	1 (1.5)	1 (1.5)	1.00	0.92 (0.05–14.88)
YAG laser capsulotomy (≤ 1-year post-op)	5 (18.5)	8 (24.2)	0.40	0.56 (0.18–1.76)
Limbal relaxing incisions	0	6 (4.2)	0.01	–

Notes: Data presented as no. of patients (%). –Unable to calculate. Bold p-value signifies statistically significant; P <0.05.

Abbreviations: CI, confidence interval; FLACS, femtosecond laser-assisted cataract surgery; OR, odds ratio; PCS, phacoemulsification cataract surgery; YAG, yttrium-aluminum garnet.