Changing indications and surgical techniques for keratoplasty during a 16-year period (2003–2018) at a tertiary referral hospital in Japan

Figures & data

Table 1 Total number of keratoplasty procedures from 2003 to 2018

Procedures	No. of cases	Percentage
DSAEK	371	46.3
PK	319	39.8
DALK	57	7.1
DMEK	45	5.6
ALK	9	1.1
Total	801

Abbreviations: ALK, anterior lamellar keratoplasty; DALK, deep anterior lamellar keratoplasty; DMEK, Descemet’s membrane endothelial keratoplasty; DSAEK, Descemet’s stripping automated endothelial keratoplasty; PK, penetrating keratoplasty.

Figure 1 Number of keratoplasty procedures by year. The total annual number of keratoplasty procedures increased from 20 in 2003 to 52 in 2018. PK and DSAEK have consistently remained as major keratoplasty types.

Abbreviations: DSAEK, Descemet’s stripping automated endothelial keratoplasty; DMEK, Descemet’s membrane endothelial keratoplasty; DALK, deep anterior lamellar keratoplasty; ALK, anterior lamellar keratoplasty; PK, penetrating keratoplasty.

Figure 2 Trends in keratoplasty procedures from 2003 to 2018. The incidence of PK procedures decreased, while the incidence of DSAEK significantly increased.

Abbreviations: DSAEK, Descemet’s stripping automated endothelial keratoplasty; DMEK, Descemet’s membrane endothelial keratoplasty; DALK, deep anterior lamellar keratoplasty; ALK, anterior lamellar keratoplasty; PK, penetrating keratoplasty.

Table 2 Underlying disease indications for PK from 2003 to 2018

Underlying disease	No. of cases	Percentage
Bullous keratopathy	120	37.6
Corneal opacity	80	25.1
Keratoconus	43	13.5
Perforation	28	8.7
Infection	20	6.3
Failed PK	19	6.0
Dystrophy	7	2.1
Failed DSAEK	2	0.6
Total	319

Abbreviations: DSAEK, Descemet’s stripping automated endothelial keratoplasty; PK, penetrating keratoplasty.

Figure 3 Trends in underlying diseases for PK from 2003 to 2018. The incidence of BK significantly decreased.

Abbreviations: BK, bullous kerstopathy; DSAEK, Descemet’s stripping automated endothelial keratoplasty; PK, penetrating keratoplasty.

Figure 4 Trends in underlying diseases for all keratoplasty procedures from 2003 to 2018. Corneal opacity and dermoid were decreasing linearly. Failed PK and failed DSAEK were increasing linearly in the beginning of the study period, but in the latter half, reached a plateau.

Abbreviations: DSAEK, Descemet’s stripping automated endothelial keratoplasty; DMEK, Descemet’s membrane endothelial keratoplasty; PK, penetrating keratoplasty.

Table 3 Underlying disease indications for all keratoplasty procedures from 2003 to 2018

Underlying disease	No. of cases	Percentage
Bullous keratopathy	440	54.9
Corneal opacity	110	13.7
Keratoconus	56	7.0
Failed DSAEK	55	6.9
Failed PK	53	6.6
Perforation	37	4.6
Infection	20	2.5
Dystrophy	14	1.7
Failed DMEK	9	1.1
Dermoid	7	0.9
Total	801

Abbreviations: DMEK, Descemet’s membrane endothelial keratoplasty; DSAEK, Descemet’s stripping automated endothelial keratoplasty; PK, penetrating keratoplasty.

Table S1 Trends in total keratoplasty procedures from 2003 to 2018 using logistic regression model analysis and Cochran-Armitage test

Keratoplasty procedures	Baseline Year	Parameter	Logisitic model parameter estimate			Hosmer-Lemeshow goodness-of-Fit test	Cochran–Armitage test for Monotonicity
	Model		Estimate	95% C.I.	P-value
PK	2003	Intercept at BL	1.917	(1.117, 2.717)	–	P=0.105	P<0.001**
	Cubic	Linear trend	−0.314	(−0.710, 0.082)	0.121
		Quadratic trend	−0.020	(−0.077, 0.037)	0.490
		Cubic trend	0.002	(0.000, 0.004)	0.116
DALK	2003	Intercept at BL	−2.218	(−3.403, −1.034)	–	P=0.068	P=0.001**
	Quartic	Linear trend	0.967	(−0.230, 2.164)	0.113
		Quadratic trend	−0.444	(−0.804, −0.083)	0.016 **
		Cubic trend	0.056	(0.017, 0.096)	0.005 **
		Quartic trend	−0.002	(−0.004, −0.001)	0.003 **
ALK	2003	Intercept at BL	−5.746	(−9.892, −1.601)	–	P=0.345	P=0.550
	Quartic	Linear trend	2.670	(−1.037, 6.378)	0.158
		Quadratic trend	−0.887	(−1.906, 0.132)	0.088
		Cubic trend	0.091	(−0.010, 0.191)	0.077
		Quartic trend	−0.003	(−0.006, 0.000)	0.080
DSAEK	2006	Intercept at BL	−1.450	(−2.038, −0.861)	–	P=0.153	P<0.001**
	Cubic	Linear trend	0.709	(0.297, 1.121)	<0.001**
		Quadratic trend	−0.086	(−0.164, −0.008)	0.030 **
		Cubic trend	0.003	(−0.001, 0.008)	0.112
DMEK	2010	Intercept at BL	−2.681	(−3.334, −2.028)	–	P=0.130	P=0.159
	Linear	Linear trend	0.088	(−0.035, 0.212)	0.161

Note: **Statistically significant.

Abbreviations: ALK, anterior lamellar keratoplasty; DALK, deep anterior lamellar keratoplasty; DMEK, Descemet’s membrane endothelial keratoplasty; DSAEK, Descemet’s stripping automated endothelial keratoplasty; PK, penetrating keratoplasty.

Table S2 Changes in the underlying diseases of PK over a 16-year period (2003 to 2018) using logistic regression model analysis and Cochran–Armitage test

Causal Disease	Baseline Year	Parameter	Logisitic model parameter estimate			Hosmer-Lemeshow Goodness-of-Fit test	Cochran–Armitage test for Monotonicity
	Model		Estimate	95% C.I.	P-value
Bullous keratopathy	2003	Intercept at BL	0.423	(−0.272, 1.118)	–	P=0.361	P<0.001**
	Cubic	Linear trend	0.035	(−0.420, 0.491)	0.879
		Quadratic trend	−0.058	(−0.139, 0.023)	0.159
		Cubic trend	0.003	(−0.001, 0.007)	0.094
Keratoconus	2003	Intercept at BL	−2.410	(−3.010, −1.810)	–	P=0.537	P=0.018**
	Linear	Linear trend	0.083	(0.013, 0.152)	0.020 **
Dystrophy	2003	Intercept at BL	−3.116	(−4.733, −1.499)	–	P=0.075	P=0.238
	Quadratic	Linear trend	−0.538	(−1.198, 0.122)	0.110
		Quadratic trend	0.040	(−0.002, 0.082)	0.061
Corneal opacity	2003	Intercept at BL	−0.894	(−1.656, −0.133)	–	P=0.593	P=0.551
	Cubic	Linear trend	−0.336	(−0.824, 0.151)	0.176
		Quadratic trend	0.083	(−0.001, 0.167)	0.053
		Cubic trend	−0.005	(−0.009, −0.001)	0.024 **
Perforation	2003	Intercept at BL	−6.009	(−9.247, −2.771)	–	P=0.646	P=0.001**
	Cubic	Linear trend	1.506	(0.086, 2.926)	0.038 **
		Quadratic trend	−0.180	(−0.368, 0.008)	0.060
		Cubic trend	0.007	(−0.001, 0.014)	0.073
Infection	2003	Intercept at BL	−3.347	(−4.223, −2.472)	–	P=0.358	P=0.053
	Linear	Linear trend	0.093	(−0.003, 0.190)	0.058
Failed PK	2003	Intercept at BL	−5.465	(−7.735, −3.195)	–	P=0.984	P=0.019**
	Quadratic	Linear trend	0.722	(0.139, 1.305)	0.015 **
		Quadratic trend	−0.036	(−0.070, −0.003)	0.033 **
Failed DSAEK	2006	Intercept at BL	−122.695	(−395.543, 150.153)	–	P=0.847	P=0.036**
	Quadratic	Linear trend	23.594	(−29.386, 76.573)	0.383
		Quadratic trend	−1.156	(−3.722, 1.410)	0.377

Note: **Statistically significant.

Abbreviations: DSAEK, Descemet’s stripping automated endothelial keratoplasty; PK, penetrating keratoplasty.

Table S3 Changes in the underlying diseases for total keratoplasty from 2003 to 2018 using logistic regression model analysis and Cochran–Armitage test

Causal Disease	Baseline Year	Parameter	Logisitic model parameter estimate			Hosmer-Lemeshow Goodness-of-Fit test	Cochran–Armitage test for Monotonicity
	Model		Estimate	95% C.I.	P-value
Bullous keratopathy	2003	Intercept at BL	0.145	(−0.149, 0.439)	–	P=0.246	P=0.688
	Linear	Linear trend	0.006	(−0.025, 0.038)	0.688
Keratoconus	2003	Intercept at BL	−2.418	(−2.972, −1.864)	–	P=0.438	P=0.499
	Linear	Linear trend	−0.021	(−0.083, 0.040)	0.500
Dystrophy	2003	Intercept at BL	−4.441	(−6.657, −2.224)	–	P=0.658	P=0.028**
	Cubic	Linear trend	1.435	(−0.014, 2.884)	0.052
		Quadratic trend	−0.343	(−0.611, −0.076)	0.012 **
		Cubic trend	0.017	(0.005, 0.029)	0.007 **
Corneal opacity	2003	Intercept at BL	−0.732	(−1.103, −0.362)	–	P=0.292	P<0.001**
	Linear	Linear trend	−0.155	(−0.205, −0.105)	<0.001 **
Perforation	2003	Intercept at BL	−5.547	(−8.340, −2.754)	–	P=0.628	P=0.261
	Cubic	Linear trend	1.078	(−0.117, 2.273)	0.077
		Quadratic trend	−0.130	(−0.284, 0.024)	0.098
		Cubic trend	0.005	(−0.001, 0.011)	0.120
Infection	2003	Intercept at BL	−3.535	(−4.446, −2.625)	–	P=0.515	P=0.754
	Linear	Linear trend	−0.016	(−0.117, 0.084)	0.754
Failed PK	2003	Intercept at BL	−4.807	(−6.378, −3.236)	–	P=0.812	P=0.024*
	Quadratic	Linear trend	0.510	(0.136, 0.884)	0.008 **
		Quadratic trend	−0.025	(−0.046, −0.004)	0.017 **
Failed DSAEK	2006	Intercept at BL	−7.621	(−10.497, −4.744)	–	P=0.639	P<0.001 **
	Quadratic	Linear trend	1.235	(0.510, 1.959)	<0.001 **
		Quadratic trend	−0.064	(−0.108, −0.020)	0.004 **
Failed DMEK	2010	Intercept at BL	−4.143	(−5.479, −2.807)	–	P=0.793	P=0.773
	Linear	Linear trend	0.038	(−0.223, 0.300)	0.773
Dermoid	2003	Intercept at BL	−3.462	(−4.662, −2.263)	–	P=0.061	P=0.035**
	Linear	Linear trend	−0.199	(−0.397, −0.001)	0.049 **

Note: **Statistically significant.

Abbreviations: DMEK, Descemet’s membrane endothelial keratoplasty; DSAEK, Descemet’s stripping automated endothelial keratoplasty; PK, penetrating keratoplasty.