
==== Front
Sci Rep
Sci Rep
Scientific Reports
2045-2322
Nature Publishing Group UK London

39261655
72444
10.1038/s41598-024-72444-6
Article
Anatomic changes in asymptomatic pachychoroid spectrum diseases after cataract surgery
Moon Kun 1
Kwon Hyunggoo 2
Jeon Sohee soheeeee@gmail.com

2
1 Seoul Balgeunsesang Eye Clinic, Seoul, Korea
2 Keye Eye Center, 326 Teheran-Ro, Gangnam-Gu, Seoul, Korea
11 9 2024
11 9 2024
2024
14 2124716 3 2023
6 9 2024
© The Author(s) 2024
2024
https://creativecommons.org/licenses/by-nc-nd/4.0/ Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
Pachychoroid spectrum disease (PSD) involves various chorioretinal pathologies associated with increased choroidal blood flow. Theoretically, PSD could worsen after cataract surgery since the choroidal thickness tends to increase after surgery. Therefore, we evaluated the prevalence of asymptomatic PSD in patients who underwent cataract surgery and compared the clinical characteristics according to the presence of PSD. The subretinal fluid (SRF) development risk was evaluated using the Cox proportional hazard model. Of 924 eyes, 184 (19.9%) showed asymptomatic PSD. Patients with asymptomatic PSD were older, predominantly male, hyperopic, and showed thicker choroid (P < 0.001, 0.001, < 0.001, and < 0.001). Seven (3.8%) of 184 eyes with asymptomatic PSD developed SRF. The Cox proportional hazard model showed that the flat, irregular pigment epithelial detect (FI-PED; HR 37.337, 95% CI 3.880–359.9300, P = 0.002) was the sole indicator for the SRF development after adjustment of age, sex, and axial length. The SRF-developed PSD group experienced a profound and prolonged increase in the choroidal thickness (P = 0.001, 0.002, and 0.002 at 1, 3, and 12 months). Meticulous preoperative evaluation for FI-PED and postoperative monitoring for choroidal thickness would predict SRF development after cataract surgery in eyes with asymptomatic PSD.

Subject terms

Neuroscience
Medical research
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pmcIntroduction

Pachychoroid spectrum disease (PSD) involves various chorioretinal pathologies associated with pachychoroid features.1–3 Central serous chorioretinopathy (CSC) and polypoidal choroidal vasculopathy (PCV) are well-known types of PSD and have been the subjects of extensive research. On the other hand, asymptomatic PSDs, such as pachychoroid pigment epitheliopathy (PPE), quiescent pachychoroid neovasculopathy (PNV), and pachydrusen have recently been classified as PSDs and have only limited information.1–10 In addition, some commonly seen pigment epithelial defect (PED) in asymptomatic eyes, such as flat-irregular PED (FI-PED) and focal PED, more severe than the small PEDs of PPE, have not been appropriately classified; They only classified as PNV and CSC when the neovascularization or subretinal fluid (SRF) develops. While PPE is mostly asymptomatic, it has been speculated to be a forme fruste of CSC, suggesting that PPE might progress to CSC when the choroidal permeability increases.5,6 In a similar vein, quiescent PNV has been suspected to be the significant precursor lesion of PCV.11.

Cataract surgery is one of the most frequently performed surgical procedures worldwide, as cataract is the most common cause of visual loss.12 Although this is controversial, the choroidal thickness tends to increase after cataract surgery.13–19 Therefore, PPE and quiescent PNV could be aggravated or progress to develop SRF when the choroidal permeability increases after cataract surgery. However, the changes in PPE or quiescent PNV lesions after cataract surgery have not been thoroughly evaluated previously. In the present study, we assessed the long-term anatomic changes in PSD after cataract surgery regarding the development of SRF and changes in the choroidal thickness.

Methods

A retrospective chart review was performed for eyes with a history of phacoemulsification and intraocular lens (IOL) implantation from January 2019 to June 2021 at the KEYE Eye Center. We included patients older than 45 years with postoperative monitoring for more than 12 months. Exclusion criteria included eyes with history of symptomatic retinal diseases, including CSC, PCV, diabetic retinopathy, retinal vascular occlusions, or any vitreoretinal surgery. Eyes with intraoperative capsular damage or any postoperative complication, such as cystoid macular edema or postoperative IOL exchange, were also excluded. Patients with malignant hypertension, pregnancy, or who reported any corticosteroid treatment during the follow-up were also excluded. Of the 2,773 eyes that underwent cataract surgery during the study period, 924 met the inclusion criteria. Those 924 eyes were included and divided into the ‘asymptomatic PSD group’ and ‘No PSD group’ according to the presence of asymptomatic PSD. Patients with asymptomatic PSD were divided into ‘Quiescent PSD group’ and ‘SRF-developed PSD group’ according to the postoperative SRF development. To evaluate postoperative changes in choroidal thickness, we randomly selected an “age, sex, and axial length-matched control group” by “individual matching” with asymptomatic PSD eyes among patients with a history of cataract surgery but no PSD.

The Institutional Review Board (IRB)/Ethics Committee of KEYE Eye Center (IRB number 2020-0724-001) approved the study and waived the requirement for informed consent because of the retrospective nature of the study. The study protocol adhered to the tenets of the Declaration of Helsinki.

Spectral-domain optical coherence tomography (SD-OCT; Spectralis, Heidelberg Engineering, Heidelberg, Germany) scans with enhanced depth imaging mode were routinely checked at baseline and postoperative months 1, 3, and 12. Obtained OCT images were carefully evaluated by two retinal specialists, blinded to the patient groups and identities using Heidelberg Eye Explorer software (version 1.10.2.0; Heidelberg Engineering). We measured the choroidal thickness between the outer part of the hyperreflective line corresponding to the retinal pigment epithelium (RPE) and the inner surface of the sclera using the calipers software tool (Fig. 1A). Pachychoroid features were defined when diffuse or focal increases in choroidal thickness, abnormally dilated Haller layer vessels, and attenuation of the Sattler’s layer vessels and choriocapillaris were detected. PPE was diagnosed when there were characteristic pachychoroid features and RPE changes, including mottling or elevation of RPE (Fig. 1B). Focal PED was diagnosed when there was a simple PED with typical pachychoroid features (Fig. 1C) but no presence or known history of SRF or soft drusen.1–4 An optical coherence tomography angiography (OCT-A) was performed when there was a FI-PED (Fig. 1D), and PNV was diagnosed when there was type 1 choroidal neovascularization, but no presence or known history of SRF or soft drusen (Fig. 1E).5,6 Pachydrusen was diagnosed when there were well-defined yellow-white deposits on the retinal photograph (Fig. 1F) that demonstrate a jagged margin around an elevated subretinal pigment epithelial accumulation above pachychoroid vessels (Fig. 1G).7,8 The axial length was measured with a partial coherence interferometry device (IOLMaster 700; Carl Zeiss Meditec AG, Jena, Germany).Fig. 1 Representative images for evaluating clinical characteristics of PSD (pachychoroid spectrum disease). (A) An optical coherence tomography (OCT) scan for choroidal thickness at the fovea (arrow). (B) An OCT scan for pachychoroid pigment epitheliopathy (arrows). (C) An OCT scan for focal pigment epithelial detachment (arrows). (D) An OCT scan for flat, irregular PED (arrow). (E) An OCT-angiography scan for pachychoroid neovasculopathy. (F) Fundus photography for pachydrusen. (G) An OCT scan of the pachydrusen.

Statistical analysis

The student’s t-test was used to compare continuous variables between groups, while the chi-squared test was used to compare categorical variables between groups. An analysis of variance (ANOVA) test was used to compare three or more data, and the Bonferroni test was used for posthoc analysis. The Shapiro–Wilk test was used to assess the normality of the continuous variables. Cox proportional hazard ratios for the development of SRF after cataract surgery in the presence of selected risk factors and demographic data were calculated. We used SPSS software version 15.0 for Windows (SPSS, Inc., Chicago, IL) for statistical analysis. Descriptive data were recorded as mean ± standard deviation unless otherwise specified. A P value of less than 0.05 was considered statistically significant.

Results

Of 924 eyes with inclusion criteria, 184 eyes (19.9%) that showed asymptomatic PSD at the time of cataract surgery were classified as ‘Asymptomatic PSD group,’ and the other 740 eyes were classified as ‘No PSD group’ (Fig. 2). Table 1 shows the clinical characteristics of enrolled eyes. Patients with asymptomatic PSD were older (59.99 ± 5.22 and 58.40 ± 6.08; P < 0.001) and predominantly male (38.0% and 24.7%; P = 0.001). A shorter axial length (23.45 ± 0.86 mm and 23.91 ± 1.36 mm; P < 0.001), and thicker choroidal thickness (355.46 ± 89.05 µm and 280.91 ± 102.24 µm; P < 0.001) were detected in the asymptomatic PSD group when compared with the no PSD group. There were no significant differences in central subfield thickness (P = 0.789). While no eye developed SRF in no PSD group within 15.69 months of follow-up, there were seven eyes (3.8%) that developed SRF in asymptomatic PSD eyes within 22.86 months of follow-up (P < 0.001).Fig. 2 Flowchart illustrating the distribution of the enrolled patients.

Table 1 Comparison of clinical characteristics of asymptomatic PSD and No PSD group (n = 924).

	Asymptomatic PSD group (n = 184)	No PSD group (n = 740)	P value	
Age, years	59.99 ± 5.22	58.40 ± 6.08	 < 0.001*	
Sex, male (%)	70 (38.0)	183 (24.7)	0.001†	
Axial length, mm	23.45 ± 0.86	23.91 ± 1.36	 < 0.001*	
Central subfield thickness, µm	264.31 ± 19.61	264.85 ± 22.40	0.789*	
Choroidal thickness, µm	355.46 ± 89.05	280.91 ± 102.24	 < 0.001*	
Follow-up, months	22.86 ± 8.17	15.69 ± 3.93	 < 0.001*	
Development of SRF (%)	7 (3.8)	0 (0.0)	 < 0.001†	
PSD pachychoroid spectrum disease, SRF subretinal fluid.

*Student’s t-test.

†Chi-squared test.

Of those 184 eyes with asymptomatic PSD, 36 eyes (19.6%) showed pachydrusen, 18 eyes (9.8%) showed Focal PED, nine eyes (4.9%) showed FI-PED, and six eyes (3.3%) showed PNV (Table 2). No eye showed both PNV and pachydrusen in the same eye. Eyes with PNV and other phenotypes, including PPE, focal PED, or FI-PED, were classified as the PNV group. Eyes with FI-PED and different phenotypes, including PPE or focal PED, were classified as the FI-PED group. There was no difference in the preoperative characteristics between groups. However, there was a significant difference in the development of SRF according to the group; five out of nine FI-PED eyes (55.6%), one of 115 PPE eyes (0.87%), and one of 18 focal PED eyes (5.6%) developed SRF. In contrast, no eyes with pachydrusen or PNV developed SRF during the follow-up. Table 2 Clinical characteristics of asymptomatic PSD eyes according to clinical characteristics (n = 184).

	PPE only (n = 115)	PD (n = 36)	Focal PED (n = 18)	FI-PED (n = 9)	PNV (n = 6)	P value*	
Age, years	59.95 ± 5.90	60.78 ± 3.75	57.83 ± 3.88	60.78 ± 3.49	61.50 ± 3.02	0.363	
Sex, male (%)	43 (37.4)	16 (13.9)	8 (44.4)	2 (22.2)	1 (16.7)	0.578	
Axial length, mm	23.39 ± 0.85	23.47 ± 0.67	23.78 ± 0.91	23.63 ± 1.28	23.09 ± 1.06	0.316	
Central subfield thickness, µm	263.94 ± 21.07	264.77 ± 17.98	263.69 ± 15.24	276.50 ± 7.45	241.33 ± 16.80	0.122	
Choroidal thickness, µm	346.19 ± 87.22	372.17 ± 88.17	374.56 ± 88.96	349.67 ± 103.74	384.33 ± 109.12	0.450	
Follow-up, months	22.56 ± 7.80	23.64 ± 8.85	20.33 ± 8.41	28.11 ± 7.70	23.67 ± 9.61	0.211	
Development of SRF (%)	1 (0.1)	0 (0.0)	1 (5.6)	5 (55.6)	0 (0.0)	 < 0.001	
FI-PED flat irregular pigment epithelial detachment, PD pachydrusen, PED pigment epithelial detachment, PNV pachychoroid neovasculopathy, PPE pachychoroid pigment epitheliopathy, PSD pachychoroid spectrum disease, SRF subretinal fluid.

*Analysis of variance (ANOVA) test.

Among those Seven eyes with SRF development (SRF-developed PSD group; 3.8% of eyes with asymptomatic PSD), two eyes (1.1%) showed SRF involving fovea (Fig. 3), while five eyes (2.7%) showed SRF elsewhere. The Cox proportional hazard model for prediction of SRF development showed that the presence of FI-PED (HR 37.337, 95% CI 3.880 – 359.9300, P = 0.002) was a sole indicator for the development of SRF in the eyes with asymptomatic PSD after adjustment of age, sex and axial length (Table 3). Other variables, such as choroidal thickness (P = 0.949), presence of pachydrusen (P = 0.410), focal PED (P = 0.090), PNV (P = 0.745) or EZ defect (P = 0.093) did not increase the risk or SRF development in asymptomatic PSD eyes.Fig. 3 Preoperative evaluation of a 55-year-old male showed a mottled appearance on fundus photography (FP; A) but no evidence of sub-retinal pigment epithelial (RPE) neovascularization on optical coherence tomography-angiography (OCT-A; B). An optical coherence tomography (OCT) showed flat irregular-pigment epithelial detachment (FI-PED) over the pachyvessels. At six months postoperatively, pinpoint leakage (D; arrow) on fluorescence angiography (FA) without definite evidence of sub-RPE neovascularization on OCT-A was detected. A substantial amount of subretinal fluid (SRF) was seen on the OCT scan (F). Since there was no improvement in the amount of SRF after two months of conservative care, We did three monthly aflibercept intravitreal injections for the suspicion of early sub-RPE neovascularization. A sustained pinpoint leakage on FA (G; arrow) without definite evidence of sub-RPE neovascularization on OCT-A (H) and SRF (I) on OCT scan was detected even after three consecutive injections.

Table 3 Cox proportional hazard model for prediction of SRF in asymptomatic PSD after cataract surgery.

	Univariate analysis	Multivariate analysis	
	HR	95% CI	P Value	HR	95% CI	P Value	
Age, years	0.990	0.858–1141	0.884				
Sex, male (%)	0.246	0.048–1.270	0.094				
Axial length, mm	2.210	0.937–5.210	0.070				
CST, µm	1.016	0.966–1.067	0.543				
Choroidal thickness, µm	1.000	0.991–1.008	0.949				
Pachydrusen, yes	0.035	0.000–100.12	0.410				
Focal PED, yes	4.141	0.803–21.349	0.090				
FI-PED, yes	14.714	3.290–65.810	 < 0.001	37.337	3.880 – 359.300	0.002	
PNV, yes	0.047	0.000–4464.724	0.745				
EZ defect, yes	3.605	0.807–16.108	0.093				
CI confidential interval, CST central subfield thickness, EZ ellipsoid zone, FI-PED flat irregular PED, HR hazard ratio, PED pigment epithelial detachment, PPE pachychoroid pigment epitheliopathy, PNV pachychoroid neovasculopathy, PSD pachychoroid spectrum disease, SRF subretinal fluid.

Table 4 shows the clinical characteristics of the quiescent PSD group (no SRF development after cataract surgery), SRF-developed PSD group, and age, sex, and axial length-matched control group. There was no difference in age (P = 0.988), sex (P = 0.173), or axial length (P = 0.223) between the three groups. The choroidal thickness significantly differed between the three groups at every time point (P < 0.001 for all comparisons; Fig. 4). At baseline, choroidal thickness was highest in the quiescent PSD group (355.58 ± 88.19 µm), followed by the SRF-developed PSD group (326.71 ± 135.88 µm) and control group (307.67 ± 114.51 µm, P < 0.001). At month 3, the choroidal thickness was highest in the SRF-developed PSD group (388.57 ± 147.65 µm), followed by the quiescent PSD group (375.03 ± 102.92 µm) and control group (327.22 ± 100.33 µm, P < 0.001). This trend was maintained for 12 months (392.57 ± 139.83 µm for the SRF-developed PSD group, 372.11 ± 96.79 µm for the asymptomatic PSD group, and 323.44 ± 100.15 µm for the control group, P < 0.001). The choroidal thickness of SRF-developed eyes increased 35.29 ± 47.35, 61.86 ± 54.50, and 65.86 ± 52.98 µm at 1, 3, and 12 months. At the same time, the quiescent PSD group showed 22.10 ± 52.69, 22.61 ± 61.72, and 16.53 ± 55.60 µm increases at corresponding time points (P > 0.999, P = 0.090, and P = 0.011 at 1, 3, and 12 months, Bonferroni test). The SRF-developed PSD group experienced a profound and prolonged increase in the choroidal thickness even 12 months after cataract surgery (Fig. 5). Table 4 Comparison of postoperative changes in the choroidal thickness of asymptomatic PSD eyes with age, sex, and AL-matched control.

	Age, sex and AL-matched control group (Control; n = 184)	Quiescent PSD group (qPSD; n = 177)	SRF-developed PSD group (SRF; n = 7)	P value*	
Age, years	59.97 ± 5.18	60.01 ± 5.29	59.71 ± 3.30	0.988	
	P > 0.999 for all comparisons†	
Sex, male (%)	70 (38.0)	65 (36.7)	5 (71.4)	0.173	
	P > 0.999 for control vs qPSD, P = 0.108 for control vs SRF group, and P = 0.107 for qPSD vs SRF group.†	
AL, mm	23.42 ± 0.94	23.42 ± 0.83	24.02 ± 1.36	0.223	
	P > 0.999 for control vs qPSD, P = 0.263 for control vs SRF group, and P = 0.256 for qPSD vs SRF group.†	
CT at baseline, µm	307.67 ± 114.51	355.58 ± 88.19	326.71 ± 135.88	 < 0.001*	
	P < 0.001 for control vs qPSD, P > 0.999 for control vs SRF group and qPSD vs SRF group.†	
CT at 1 month, µm	325.81 ± 100.42	377.00 ± 97.63	366.57 ± 143.21	 < 0.001*	
	P < 0.001 for control vs qPSD, P = 0.874 for control vs SRF group, and P > 0.999 for qPSD vs SRF group.†	
CT at 3 month, µm	327.22 ± 100.33	375.03 ± 102.92	388.57 ± 147.65	 < 0.001*	
	P < 0.001 for control vs qPSD, P = 0.367 for control vs SRF group, and P > 0.999 for qPSD vs SRF group.†	
CT at 12 month, µm	323.44 ± 100.15	372.11 ± 96.79	392.57 ± 139.83	 < 0.001*	
	P < 0.001 for control vs qPSD, P = 0.217 for control vs SRF group, and P > 0.999 for qPSD vs SRF group.†	
ΔCT at 1 month, µm	4.48 ± 36.53	22.10 ± 52.69	35.29 ± 47.35	0.001*	
	P = 0.001 for control vs qPSD, P = 0.241 for control vs SRF group, and P > 0.999 for qPSD vs SRF group.†	
ΔCT at 3 month, µm	9.77 ± 22.75	22.61 ± 61.72	61.86 ± 54.50	0.002	
	P = 0.039 for control vs qPSD, P = 0.012 for control vs SRF group, and P = 0.090 for qPSD vs SRF group.†	
ΔCT at 12 month, µm	9.44 ± 23.24	16.53 ± 55.60	65.86 ± 52.98	0.002	
	P = 0.409 for control vs qPSD, P = 0.003 for control vs SRF group, and P = 0.011 for qPSD vs SRF group.†	
ΔCT difference in the choroidal thickness between baseline and each follow-up.

AL axial length, CT choroidal thickness, qPSD quiescent pachychoroid spectrum disease, PSD pachychoroid spectrum disease, SRF subretinal fluid.

*Analysis of variance (ANOVA) test.

†Bonferroni test.

Fig. 4 Bar graphs show changes in choroidal thickness from eyes with age, sex, axial length-matched control, quiescent pachychoroid spectrum disease (PSD) eyes, and subretinal fluid (SRF) developed PSD eyes. *P < 0.05.

Fig. 5 Preoperative evaluation of a 60-year-old female showed perifoveal pachydrusen on fundus photography (FP; A) without evidence of sub-retinal pigment epithelial (RPE) neovascularization on optical coherence tomography-angiography (OCT-A; B). An optical coherence tomography (OCT) showed sub-RPE deposits over the pachyvessels (C). Three years later, the pachydrusen was diminished on FP without evidence of sub-RPE neovascularization on OCT-A (D). The OCT scan showed flat irregular-pigment epithelial detachment (FI-PED)-like lesions. There was no development of subretinal fluid during the follow-up period.

Discussion

Asymptomatic PSD was detected in 19.9% of our cohort. The prevalence of PSD has not been evaluated thoroughly, as it is usually asymptomatic and cannot be detected by standard screening tools such as fundus photography. Our study suggests that asymptomatic PSD is common among patients who are planning cataract surgery, especially in the eyes of older males with short axial length and thick choroids. We found that only 3.8% of eyes with asymptomatic PSD developed SRF within one year after uneventful cataract surgery, and the macular involvement was seen in 1.1%. Previously, Karacorlu et al. reported that 17.4% of eyes with PPE in fellow eyes of patients with unilateral CSC developed CSC within three years.16 The risk of SRF development in patients with asymptomatic PSD lesions should be evaluated in a comprehensive risk analysis encompassing age, past history, type of lesion, and choroidal vulnerability. Our cohort at the age of cataract surgery has passed the peak age of CSC without developing SRF. Furthermore, the choroidal thickness was lower than the cohort from the study by Karacorlu et al., which would all contribute to the lower incidence of SRF in the present study.

Of interest, we detected no SRF development from six eyes with evident PNV during the 23.67 months of follow-up (Fig. 6). Furthermore, they did not know the presence of macular disease until the preoperative evaluation, suggesting some PNV lesions slowly progress and spontaneously turn into an inactive state. These inactive PNV lesions were not aggravated by uneventful cataract surgery in the present cohort. On the contrary, the presence of FI-PED increased the risk of the development of SRF with a hazard ratio of 37.337. We speculated that the FI-PED lesions that developed SRF were a latent period of the disease, which could be aggravated by cataract surgery and other risk factors that increase choroidal blood flow. Further study to identify the latent period FI-PED, using angiography would help minimize SRF development after uneventful cataract surgery.Fig. 6 Preoperative evaluation of a 63-year-old female showed a mottled appearance on fundus photography (FP; A) with sub-retinal pigment epithelial (RPE) neovascularization on optical coherence tomography angiography (OCT-A; B). An optical coherence tomography (OCT) showed flat irregular-pigment epithelial detachment (FI-PED) over the pachyvessels. During three years of postoperative follow-up, there was no change in the FP (D), OCT-A (E), or OCT scan (F). There was no development of subretinal fluid during the follow-up period.

It has been speculated that an FI-PED is a presumptive sign of sub-RPE neovascularization in eyes with pachychoroid.17–21 In these cases, OCT-A has a significant role in confirming sub-RPE neovascularization that cannot be detected by conventional fluorescence angiography. In the present cohort, sub-RPE neovascularization was seen in 40% of eyes with FI-PED by OCT-A. In addition, we have found that the pachydrusen evolved into FI-PED-like lesions, which showed no sub-RPE neovascularization in long-term observation (Fig. 5). We speculate that FI-PED represents the various clinical status of PSD regarding not only subclinical neovascularization but also pachydrusen or fibrotic change from advanced stage of chronic CSC.This finding indicates that the specific phenotype of PSD may not be a good indicator for SRF development after cataract surgery, instead raising the necessity of discovering new parameters representing choroidal vulnerability.

We found that the choroidal thickness of the SRF-developed PSD group was lower than that of quiescent PSD eyes preoperatively. However, the choroidal thickness of the SRF-developed PSD group increased immediately and continued the increase throughout the postoperative 12 months, while the quiescent PSD group increased in the early postoperative period and decreased after that. We speculate that the profound and prolonged increase in choroidal thickness would be a good marker for the choroidal vulnerability, the hidden contributing factor for the SRF development in eyes with asymptomatic PSD.21.

The incidence of SRF development after cataract surgery in eyes with asymptomatic PSD was low. Only 1.1% of eyes developed SRF on macular lesions after cataract surgery. However, half of the eyes with FI-PED experienced SRF development within a year of the postoperative follow-up. Meticulous preoperative evaluation for FI-PED and angiographic evaluation for an occult SRF would lower the risk of SRF development after cataract surgery in eyes with asymptomatic PSD.

Author contributions

KM and SJ wrote the main manuscript text, and HK prepared figures. All authors reviewed the manuscript.

Data availability

The datasets used and/or analysed during the current study available from the corresponding author on reasonable request.

Competing interests

The authors declare no competing interests.

Ethics approval

The research was conducted in accordance with the tenets of the Declaration of Helsinki and approved by the Institutional Review Board (IRB)/Ethics Committee of KEYE EYE Center (IRB number 2020-0724-001).

Publisher's note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
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