Seung Pil Bang

Prof. Seung Pil Bang

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Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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18 November 2019 in PLOS ONE
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Journal Article
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Seung Pil BangSeung Pil Bang
Seung Pil Bang
CYChang Yeor Yeon
Chang Yeor Yeon
NANirpesh Adhikari
Nirpesh Adhikari
SNSanjiv Neupane
Sanjiv Neupane
HKHarim Kim
Harim Kim
JJJong Hwa Jun
Jong Hwa Jun
We aimed to compare the physicochemical properties and in vivo efficacy of commercially available nanoemulsion cyclosporine A (CsA) eyedrops in benzalkonium chloride (BAC)-induced dry eye disease (DED). Particle size analysis was performed on conventional 0.05% CsA (Restasis, C-CsA) and two new types of 0.05% CsA eyedrops based on a self-nanoemulsifying drug delivery system (SNEDDS, SNEDDS-N and -T). Turbidometry, pH measurements and instability indices of each CsA solution were measured. DED was induced with BAC, and animals were treated with vehicle or CsA preparations. Tear volume and fluorescein staining scores were evaluated on days 7 and 14. Eyes were enucleated and subjected to IHC, TUNEL staining, periodic acid-Schiff (PAS) staining, real-time PCR and western blotting. Both SNEDDSs had lower and more uniform particle size distribution than C-CsA, and a similar optical density to phosphate-buffered saline and stable pH, in contrast to the high turbidity and unstable pH of C-CsA. Aqueous tear volume and fluorescein staining scores were improved in C-CsA- and SNEDDS-treated mice. Numbers of PAS-positive goblet cells and levels of inflammatory mediators were decreased by both C-CsA and SNEDDS, although SNEDDS resolved inflammation more effectively than C-CsA. Cyclosporine A eyedrops with SNEDDS have improved physicochemical properties and treatment efficacy in BAC-induced DED.

13 July 2021 in Annual Review of Biomedical Engineering
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Journal Article
Open access
SMSusana Marcos
Susana Marcos
EMEduardo Martinez-Enriquez
Eduardo Martinez-Enriquez
MVMaria Vinas
Maria Vinas
ACAlberto de Castro
Alberto de Castro
CDCarlos Dorronsoro
Carlos Dorronsoro
PAPablo Artal
Pablo Artal
As the human eye ages, the crystalline lens stiffens (presbyopia) and opacifies (cataract), requiring its replacement with an artificial lens [intraocular lens (IOL)]. Cataract surgery is the most frequently performed surgical procedure in the world. The increase in IOL designs has not been paralleled in practice by a sophistication in IOL selection methods, which rely on limited anatomical measurements of the eye and the surgeon's interpretation of the patient's needs and expectations. We propose that the future of IOL selection will be guided by 3D quantitative imaging of the crystalline lens to map lens opacities, anticipate IOL position, and develop fully customized eye models for ray-tracing-based IOL selection. Conversely, visual simulators (in which IOL designs are programmed in active elements) allow patients to experience prospective vision before surgery and to make more informed decisions about which IOL to choose. Quantitative imaging and optical and visual simulations of postsurgery outcomes will allow optimal treatments to be selected for a patient undergoing modern cataract surgery.

2 November 2017 in BMC Ophthalmology
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Seung Pil BangSeung Pil Bang
Seung Pil Bang
CLChong Eun Lee
Chong Eun Lee
YKYu Cheol Kim
Yu Cheol Kim
To compare the measurement of intraocular pressure (IOP) among the three different non-contact tonometers (NCT) and the Goldmann applanation tonometer (GAT) for non-glaucomatous subjects. In 52 eyes of 52 non-glaucomatous subjects, IOP was measured sequentially with the Canon TX-20P, the Nidek NT-530P, the Topcon CT-1P, and the GAT at the same time. We evaluated the IOP-measurement agreement among the tonometers as well as the factors affecting the measurements. A significant positive correlation was shown between the IOP values obtained with GAT and each NCT. The Canon TX-20P showed statistically the most significant agreement with the GAT (ICC 0.906, 95% CI 0.837–0.946). In an analysis of the Bland-Altman plots, the Canon TX-20P also showed the largest mean bias (1.38 mmHg) but the narrowest limits of agreement (LoA) (95% LoA; ± 3.43 mmHg). The Topcon CT-1P showed the smallest mean bias (0.48 mmHg) but the widest LoA (95% LoA; ± 4.16 mmHg). The Topcon CT-1P and Nidek NT-530P both showed a significantly positive correlation between increasing central corneal thickness (CCT) and increasing IOP. There was a statistically significant correlation between each of the three different NCT and the GAT measurements. IOP measured with the Canon TX-20P and Topcon CT-1P tended to be higher, and with the Nidek NT-530P lower, than with the GAT. Practitioners need to know the properties of their own NCTs and their respective measurement tendencies.

18 October 2021 in PLOS ONE
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YLYou Hyun Lee
You Hyun Lee
Seung Pil BangSeung Pil Bang
Seung Pil Bang
KSKyu-Young Shim
Kyu-Young Shim
MSMyung-Jin Son
Myung-Jin Son
HKHarim Kim
Harim Kim
JJJong Hwa Jun
Jong Hwa Jun
Purpose: This study aimed to analyze the association of tear matrix metalloproteinase 9 (MMP-9) immunoassay with the severity of dry eye (DE) signs and symptoms through qualitative, semiquantitative, and quantitative evaluations of immunoassay band. Materials and methods: This cross-sectional study enrolled 320 eyes of 320 patients. The clinical signs of DE were assessed using the Ocular Surface Disorder Index (OSDI) score, visual analogue scale (VAS), tear breakup time (tBUT), tear volume evaluation by tear meniscometry, and staining scores of the cornea and conjunctiva by the Oxford grading scheme. The tear MMP-9 immunoassay results were interpreted using qualitative (positive or negative), semi-quantitative (reagent band density on a four-point scale: 0 = negative; 1 = weakly positive; 2 = moderately positive; 3 = strongly positive), and quantitative (ratio of reagent band density to control band density) indicators. Results: Positive MMP-9 immunoassay results were significantly related to shorter tBUT, tBUT ≤3 seconds, higher corneal staining score, corneal staining score ≥2, and conjunctival staining score ≥2. The semi-quantitative results of the MMP-9 immunoassay were positively correlated with higher corneal staining score (r = 0.122, p = 0.029) and negatively correlated with tBUT (r = -0.125, p = 0.025). However, in the quantitative analysis, none of the DE signs or symptoms were correlated to the band density of the MMP-9 immunoassay. Conclusions: The positive MMP-9 immunoassay results were related to the severity of ocular signs of DE. However, using quantitative measures of the MMP-9 immunoassay to assess the clinical severity of DE requires further investigation.

29 March 2017 in BMC Ophthalmology
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Seung Pil BangSeung Pil Bang
Seung Pil Bang
CJChoun-Ki Joo
Choun-Ki Joo
JJJong Hwa Jun
Jong Hwa Jun
To report the clinical features of patients with reverse pupillary block (RPB) after scleral-sutured posterior chamber intraocular lens (PC IOL) implantation and biometric changes after laser peripheral iridotomy (LPI). Eight patients attending our hospital’s ophthalmology outpatient clinic, who developed RPB after implantation of a scleral-sutured PC IOL due to subluxation of the crystalline lens or IOL, were investigated in this retrospective, observational study. Preoperative evaluations showed angle pigmentation in all cases and iridodonesis in 2 cases. Two subjects had used an α1A-adrenoceptor antagonist for benign prostatic hyperplasia. Pars plana or anterior partial vitrectomy was performed in all cases. All eyes showed an extremely deep anterior chamber, a concave iris configuration, and contact between the IOL optic and the iris at the pupillary margin. Pupil capture was detected in 2 cases. The mean (± SD) anterior chamber angle (ACA) was 89.91 ± 10.06°, and the anterior chamber depth (ACD) was 4.42 ± 0.16 mm before LPI. After LPI, the iris immediately became flat with a decreased ACA (51.70 ± 2.59°; P = 0.018) and ACD (4.14 ± 0.15 mm; P = 0.012). After LPI, the intraocular pressure decreased from 19.75 ± 3.77 mmHg to 15.63 ± 4.30 mmHg (P = 0.011), and the spherical equivalent decreased from -0.643 ± 0.385 D to − 0.875 ± 0.505 D (P = 0.016). Concomitant vitrectomy, angle pigmentation, and iridodonesis may be risk factors for RPB after scleral-sutured PC IOL implantation. LPI is effective for relieving the RPB.

15 September 2020 in Scientific Reports
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Seung Pil BangSeung Pil Bang
Seung Pil Bang
MSMyeong Jin Son
Myeong Jin Son
HKHarim Kim
Harim Kim
YLYou Hyun Lee
You Hyun Lee
JJJong Hwa Jun
Jong Hwa Jun
We aimed to validate a tear MMP-9 in-situ immunoassay (InflammaDry) and to identify factors that could affect results or interpretation. Three factors were examined: sample concentration, volume, and time. Recombinant human (rh) MMP-9 (10 or 20 μl; 0, 12.5, 25, 50, 100, 200, 500, and 1,000 ng/ml) was applied to the kit and the detection limit and assay reproducibility were examined. At a rhMMP-9 volume of 10 μl (≥ 50 ng/ml), all positive results were identified by densitometry at 10 and 20 min; however, after 20 min, more than half of the nine ophthalmologists interpreted a positive result. At a rhMMP-9 volume of 20 μl (≥ 25 ng/ml), ophthalmologists and densitometry identified almost all test lines at 10 and 20 min. At 10 μl, densitometry showed a linear dose–response pattern. At 20 μl, densitometry showed a linear dose–response pattern at concentrations up to 500 ng/ml; however, full saturation was achieved at concentrations ≥ 500 ng/ml. When the same amount of rhMMP-9 was applied, the density result increased significantly upon doubling of the solvent volume (i.e., by adding the same volume of PBS to a sample). InflammaDry showed a high inter- and intra-assay coefficient of variation at 10 min (28.4% and 24.7%, respectively). The results of the MMP-9 in-situ immunoassay varied significantly depending on sample volume. Therefore, when interpreting the results, careful attention must be paid to tear volume.