1.Effect of 50-Hz Filters on Pattern Electroretinogram
Dong Hee HA ; Nam Ju MOON ; Ungsoo Samuel KIM
Korean Journal of Ophthalmology 2025;39(3):241-245
Purpose:
Pattern electroretinogram (PERG) is used to evaluate the function of retinal ganglion cells. However, the amplitude of PERG is quite small, making the examination challenging to perform. Waveform noise may be minimized by applying various filters. We aimed to investigate the effect of 50-Hz filters on PERG test results.
Methods:
This is the retrospective observational study. PERG tests were performed using the RETI-scan system according to the International Society for Clinical Electrophysiology of Vision guidelines. Three types of 50-Hz filters (soft, middle, and hard) were applied. The differences in parameters (N35 peak time, P50 peak time, N95 peak time, P50 amplitude, N95 amplitude, and N95 to P50 ratio) were analyzed. Based on the provided normal range, the changes from normal to abnormal range or vice versa were investigated.
Results:
A total of 24 waveforms were analyzed. After filtering, the P50 and N95 amplitudes showed a significant reduction of 8% to 15% (P50 amplitude: 5.1 ± 2.7 μV without filter, 4.6 ± 2.3 μV with 50-Hz soft filter, 4.3 ± 2.1 μV with 50-Hz middle filter, 4.3 ± 2.1 μV with 50-Hz hard filter; N95 amplitude: 7.2 ± 4.2 μV without filter, 6.6 ± 3.8 μV with 50-Hz soft filter, 6.3 ± 3.6 μV with 50-Hz middle filter, 6.1 ± 3.6 μV with 50-Hz hard filter). This pattern was more prominent in normal subjects. All latencies except the N35 peak time exhibited no differences between the tests. The N95 to P50 ratio decreased after 50-Hz middle and hard filtering. Considering the normative data, switching between normal and abnormal results was rare.
Conclusions
Although peak time was not significantly affected, amplitude was significantly reduced after using 50-Hz filters. Thus, 50-Hz filters can smoothen the waveform. Nevertheless, caution must be exercised while taking readings.
2.Effect of 50-Hz Filters on Pattern Electroretinogram
Dong Hee HA ; Nam Ju MOON ; Ungsoo Samuel KIM
Korean Journal of Ophthalmology 2025;39(3):241-245
Purpose:
Pattern electroretinogram (PERG) is used to evaluate the function of retinal ganglion cells. However, the amplitude of PERG is quite small, making the examination challenging to perform. Waveform noise may be minimized by applying various filters. We aimed to investigate the effect of 50-Hz filters on PERG test results.
Methods:
This is the retrospective observational study. PERG tests were performed using the RETI-scan system according to the International Society for Clinical Electrophysiology of Vision guidelines. Three types of 50-Hz filters (soft, middle, and hard) were applied. The differences in parameters (N35 peak time, P50 peak time, N95 peak time, P50 amplitude, N95 amplitude, and N95 to P50 ratio) were analyzed. Based on the provided normal range, the changes from normal to abnormal range or vice versa were investigated.
Results:
A total of 24 waveforms were analyzed. After filtering, the P50 and N95 amplitudes showed a significant reduction of 8% to 15% (P50 amplitude: 5.1 ± 2.7 μV without filter, 4.6 ± 2.3 μV with 50-Hz soft filter, 4.3 ± 2.1 μV with 50-Hz middle filter, 4.3 ± 2.1 μV with 50-Hz hard filter; N95 amplitude: 7.2 ± 4.2 μV without filter, 6.6 ± 3.8 μV with 50-Hz soft filter, 6.3 ± 3.6 μV with 50-Hz middle filter, 6.1 ± 3.6 μV with 50-Hz hard filter). This pattern was more prominent in normal subjects. All latencies except the N35 peak time exhibited no differences between the tests. The N95 to P50 ratio decreased after 50-Hz middle and hard filtering. Considering the normative data, switching between normal and abnormal results was rare.
Conclusions
Although peak time was not significantly affected, amplitude was significantly reduced after using 50-Hz filters. Thus, 50-Hz filters can smoothen the waveform. Nevertheless, caution must be exercised while taking readings.
3.Effect of 50-Hz Filters on Pattern Electroretinogram
Dong Hee HA ; Nam Ju MOON ; Ungsoo Samuel KIM
Korean Journal of Ophthalmology 2025;39(3):241-245
Purpose:
Pattern electroretinogram (PERG) is used to evaluate the function of retinal ganglion cells. However, the amplitude of PERG is quite small, making the examination challenging to perform. Waveform noise may be minimized by applying various filters. We aimed to investigate the effect of 50-Hz filters on PERG test results.
Methods:
This is the retrospective observational study. PERG tests were performed using the RETI-scan system according to the International Society for Clinical Electrophysiology of Vision guidelines. Three types of 50-Hz filters (soft, middle, and hard) were applied. The differences in parameters (N35 peak time, P50 peak time, N95 peak time, P50 amplitude, N95 amplitude, and N95 to P50 ratio) were analyzed. Based on the provided normal range, the changes from normal to abnormal range or vice versa were investigated.
Results:
A total of 24 waveforms were analyzed. After filtering, the P50 and N95 amplitudes showed a significant reduction of 8% to 15% (P50 amplitude: 5.1 ± 2.7 μV without filter, 4.6 ± 2.3 μV with 50-Hz soft filter, 4.3 ± 2.1 μV with 50-Hz middle filter, 4.3 ± 2.1 μV with 50-Hz hard filter; N95 amplitude: 7.2 ± 4.2 μV without filter, 6.6 ± 3.8 μV with 50-Hz soft filter, 6.3 ± 3.6 μV with 50-Hz middle filter, 6.1 ± 3.6 μV with 50-Hz hard filter). This pattern was more prominent in normal subjects. All latencies except the N35 peak time exhibited no differences between the tests. The N95 to P50 ratio decreased after 50-Hz middle and hard filtering. Considering the normative data, switching between normal and abnormal results was rare.
Conclusions
Although peak time was not significantly affected, amplitude was significantly reduced after using 50-Hz filters. Thus, 50-Hz filters can smoothen the waveform. Nevertheless, caution must be exercised while taking readings.
4.Effect of 50-Hz Filters on Pattern Electroretinogram
Dong Hee HA ; Nam Ju MOON ; Ungsoo Samuel KIM
Korean Journal of Ophthalmology 2025;39(3):241-245
Purpose:
Pattern electroretinogram (PERG) is used to evaluate the function of retinal ganglion cells. However, the amplitude of PERG is quite small, making the examination challenging to perform. Waveform noise may be minimized by applying various filters. We aimed to investigate the effect of 50-Hz filters on PERG test results.
Methods:
This is the retrospective observational study. PERG tests were performed using the RETI-scan system according to the International Society for Clinical Electrophysiology of Vision guidelines. Three types of 50-Hz filters (soft, middle, and hard) were applied. The differences in parameters (N35 peak time, P50 peak time, N95 peak time, P50 amplitude, N95 amplitude, and N95 to P50 ratio) were analyzed. Based on the provided normal range, the changes from normal to abnormal range or vice versa were investigated.
Results:
A total of 24 waveforms were analyzed. After filtering, the P50 and N95 amplitudes showed a significant reduction of 8% to 15% (P50 amplitude: 5.1 ± 2.7 μV without filter, 4.6 ± 2.3 μV with 50-Hz soft filter, 4.3 ± 2.1 μV with 50-Hz middle filter, 4.3 ± 2.1 μV with 50-Hz hard filter; N95 amplitude: 7.2 ± 4.2 μV without filter, 6.6 ± 3.8 μV with 50-Hz soft filter, 6.3 ± 3.6 μV with 50-Hz middle filter, 6.1 ± 3.6 μV with 50-Hz hard filter). This pattern was more prominent in normal subjects. All latencies except the N35 peak time exhibited no differences between the tests. The N95 to P50 ratio decreased after 50-Hz middle and hard filtering. Considering the normative data, switching between normal and abnormal results was rare.
Conclusions
Although peak time was not significantly affected, amplitude was significantly reduced after using 50-Hz filters. Thus, 50-Hz filters can smoothen the waveform. Nevertheless, caution must be exercised while taking readings.
5.Effect of 50-Hz Filters on Pattern Electroretinogram
Dong Hee HA ; Nam Ju MOON ; Ungsoo Samuel KIM
Korean Journal of Ophthalmology 2025;39(3):241-245
Purpose:
Pattern electroretinogram (PERG) is used to evaluate the function of retinal ganglion cells. However, the amplitude of PERG is quite small, making the examination challenging to perform. Waveform noise may be minimized by applying various filters. We aimed to investigate the effect of 50-Hz filters on PERG test results.
Methods:
This is the retrospective observational study. PERG tests were performed using the RETI-scan system according to the International Society for Clinical Electrophysiology of Vision guidelines. Three types of 50-Hz filters (soft, middle, and hard) were applied. The differences in parameters (N35 peak time, P50 peak time, N95 peak time, P50 amplitude, N95 amplitude, and N95 to P50 ratio) were analyzed. Based on the provided normal range, the changes from normal to abnormal range or vice versa were investigated.
Results:
A total of 24 waveforms were analyzed. After filtering, the P50 and N95 amplitudes showed a significant reduction of 8% to 15% (P50 amplitude: 5.1 ± 2.7 μV without filter, 4.6 ± 2.3 μV with 50-Hz soft filter, 4.3 ± 2.1 μV with 50-Hz middle filter, 4.3 ± 2.1 μV with 50-Hz hard filter; N95 amplitude: 7.2 ± 4.2 μV without filter, 6.6 ± 3.8 μV with 50-Hz soft filter, 6.3 ± 3.6 μV with 50-Hz middle filter, 6.1 ± 3.6 μV with 50-Hz hard filter). This pattern was more prominent in normal subjects. All latencies except the N35 peak time exhibited no differences between the tests. The N95 to P50 ratio decreased after 50-Hz middle and hard filtering. Considering the normative data, switching between normal and abnormal results was rare.
Conclusions
Although peak time was not significantly affected, amplitude was significantly reduced after using 50-Hz filters. Thus, 50-Hz filters can smoothen the waveform. Nevertheless, caution must be exercised while taking readings.
6.Central Anticholinergic Syndrome Induced by Atropine Eye Drops: A Case Report
Jung Sun HEO ; Je Jin LEE ; Sang Uk CHOI ; Nam Ju MOON ; Joon Hyung YEO
Journal of the Korean Ophthalmological Society 2024;65(11):745-748
Purpose:
We present a case of central anticholinergic syndrome following the administration of atropine eye drops.Case summary: A 60-year-old male presented with decreased visual acuity in his left eye and was diagnosed with intraocular lens dislocation. Preoperatively, Isopto atropine® eye drops (1 drop at 15-minutes intervals) were used for pupil dilation. Within an hour of the first instillation, the patient exhibited drowsiness, disorientation, agitation, and urinary retention. Laboratory tests and computed tomography of the brain were unremarkable. Considering the recent administration of atropine eye drops, a diagnosis of central anticholinergic syndrome was made. The surgery was postponed and the patient recovered fully after 3 hours of observation. He remained asymptomatic during an additional day of hospitalization.
Conclusions
A small dose of atropine eye drops even at a therapeutic dose can induce central anticholinergic syndrome. Therefore, ophthalmologists should be aware of this rare and severe complication.
7.Central Anticholinergic Syndrome Induced by Atropine Eye Drops: A Case Report
Jung Sun HEO ; Je Jin LEE ; Sang Uk CHOI ; Nam Ju MOON ; Joon Hyung YEO
Journal of the Korean Ophthalmological Society 2024;65(11):745-748
Purpose:
We present a case of central anticholinergic syndrome following the administration of atropine eye drops.Case summary: A 60-year-old male presented with decreased visual acuity in his left eye and was diagnosed with intraocular lens dislocation. Preoperatively, Isopto atropine® eye drops (1 drop at 15-minutes intervals) were used for pupil dilation. Within an hour of the first instillation, the patient exhibited drowsiness, disorientation, agitation, and urinary retention. Laboratory tests and computed tomography of the brain were unremarkable. Considering the recent administration of atropine eye drops, a diagnosis of central anticholinergic syndrome was made. The surgery was postponed and the patient recovered fully after 3 hours of observation. He remained asymptomatic during an additional day of hospitalization.
Conclusions
A small dose of atropine eye drops even at a therapeutic dose can induce central anticholinergic syndrome. Therefore, ophthalmologists should be aware of this rare and severe complication.
8.Effects of Resilience, Family Support, and Spiritual Well-Being on Posttraumatic Growth in Patients with Lung Cancer Undergoing Chemotherapy
Ha Young MOON ; Ki Sook NAM ; Hye Won OH ; Yeon Soo CHO ; Ju Yeon CHOI
Journal of Korean Clinical Nursing Research 2024;30(2):147-156
Purpose:
The purpose of this study is to confirm the effect of resilience, family support, and spiritual well-being on posttraumatic growth(PTG) in lung cancer patients undergoing chemotherapy.
Methods:
The study collected data from January 20 to July 6, 2023 on 124 lung cancer patients who were admitted to hospital of C university in Seoul and received chemotherapy treatment. Patients were asked to complete a questionnaire consisting of general characteristics, disease characteristics, resilience, family support, spiritual well-being and PTG. Data were analyzed using t-tests, One-way ANOVA, Pearson's correlation and multiple regression analysis.
Results:
The mean score for PTG in lung cancer patients was 55.17, resilience was 72.46, family support was 49.00, and spiritual well-being was 53.50. Significant positive correlations were found for PTG with resilience (r=.62, p<.001), family support (r=.40, p<.001) and spiritual well-being (r=.47, p<.001). Factors contributing to PTG of lung cancer patients were resilience (β=.50, p<.001), spiritual well-being (β=.20, p=.008), and gender (β =.14, p=.043).
Conclusion
This study aims to provide basic data for the PTG intervention program by identifying factors affecting the PTG of lung cancer patients. It is necessary to develop new nursing intervention programs to improve PTG for patients with lung cancer based on strategies to enhance resilience and spiritual well-being.
9.Effect of Temporal Decentration of Orthokeratologic Lens on Corneal Aberrations in Swept-source Optical Coherence Tomography
Jung Sun HEO ; Nam Ju MOON ; Kyoung Woo KIM
Journal of the Korean Ophthalmological Society 2024;65(5):309-319
Purpose:
This study used anterior segment swept-source optical coherence tomography (AS SS-OCT) to explore the effect of temporal decentration within the orthokeratologic lens treatment zone on corneal aberrations.
Methods:
After lens placement, AS SS-OCT was used to evaluate anterior, posterior, and total corneal astigmatism and the magnitudes of the individual 1st- to 4th-order aberrations of the anterior and entire corneal fields. Also, the 4th-to 7th-order root mean square (RMS), and the low- and high-ordered RMSs of both the anterior and entire corneal areas were recorded. We compared subjects lacking (the no decentration [ND] group) to those exhibiting (the temporal decentration [TD] group) temporal decentration.
Results:
In all, 61 eyes of 32 patients (44 eyes in the ND group and 17 in the TD group) were included. In the TD group, the average temporal decentration was 0.74 ± 0.15 mm. The baseline axial length, spherical equivalent, anterior mean corneal power, and anterior corneal astigmatism did no difference between the two groups. However, the TD group exhibited more anterior and total corneal horizontal tilts, and horizontal coma, than the ND group. That group also had less with-the-rule (WTR)/against-therule (ATR) astigmatism, elevated anterior and total corneal 5th-order RMS values, and greater low- and high-ordered RMS levels. However, despite these differences, the extent of myopia correction did not significantly differ between the groups.
Conclusions
Although myopia reduction was not significantly compromised by temporal decentration of an orthokeratologic lens, the anterior and total corneal low- and high-ordered RMS values increased. In terms of individual aberrations, the low-ordered horizontal tilt and the high-ordered horizontal coma increased.
10.The role of PD-1/PD-L1 pathway in ulcerative colitis and changes following tonsil-derived mesenchymal stem cells treatment
Eun Mi SONG ; Yang Hee JOO ; Sung-Ae JUNG ; Ju-Ran BYEON ; A-Reum CHOE ; Yehyun PARK ; Chung Hyun TAE ; Chang Mo MOON ; Seong-Eun KIM ; Hye-Kyung JUNG ; Ki-Nam SHIM
The Korean Journal of Internal Medicine 2024;39(6):917-930
Background/Aims:
The programmed death 1 (PD-1)/programmed death-ligand 1 (PD-L1) pathway has not been fully evaluated in inflammatory bowel disease. We evaluated PD-1/PD-L1 levels in patients with ulcerative colitis (UC) and their significance in tonsil-derived mesenchymal stem cells (TMSCs) treatment.
Methods:
Using acute and chronic murine colitis model, we measured the PD-1 and PD-L1 levels in inflamed colonic tissues pre- and post-treatment with TMSCs. We also measured PD-1 and PD-L1 levels in colonic tissues from UC patients, compared to normal controls.
Results:
In the analysis using human colonic tissues, a significant increase in the levels of PD-1 and PD-L1 was observed in the colonic mucosa of patients with UC compared with normal controls (p < 0.001 and p = 0.005, respectively). When comparing the maximal disease extent, PD-L1 levels were highest in patients with proctitis (38.5 ± 46.7), followed by left-side colitis (17.5 ± 23.1) and extensive colitis (5.2 ± 8.2) (p < 0.001). In the chronic colitis model, the level of PD-L1 was decreased (p = 0.040) and the level of PD-1 increased more than in normal controls (p = 0.047). After treatment with TMSC, significant improvements were observed in body weight, disease activity index, and colon length recovery. Additionally, the levels of PD-1 and PD-L1 were recovered; PD-L1 significantly increased (p = 0.031), while the level of PD-1 decreased (p = 0.310).
Conclusions
The altered expression of PD-1 and PD-L1 in colonic mucosa may be a possible mechanism of UC, and T-MSC-derived PD-L1 could help suppress colitis.

Result Analysis
Print
Save
E-mail