REPEATABILITY OF MACULAR MICROVASCULATURE MEASUREMENTS USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY ACCORDING TO TEAR BREAKUP TIME IN DRY EYE DISEASE.

PURPOSE: It is hypothesized that an unstable tear film would affect the quality and repeatability of optical coherence tomography angiography (OCTA). Therefore, OCTA repeatability according to tear break-up time (TBUT) was compared. METHODS: The 3 × 3 OCTA was performed twice and, the eyes were divided into 3 groups according to the TBUT (Group 1: TBUT ≤ 5 seconds, 43 eyes; Group 2: 5 seconds < TBUT ≤ 10 seconds, 35 eyes; Group 3: TBUT > 10 seconds, 34 eyes). The intraclass correlation coefficient, coefficient of variation, and test-retest SD were calculated and compared. RESULTS: The signal strengths of OCTA were 9.1 ± 1.2, 9.5 ± 0.8, and 9.5 ± 0.8 in each group from Groups 1, 2, and 3, respectively, which showed significant difference (P = 0.049). The intraclass correlation coefficient of vessel density were 0.733, 0.840, and 0.974 in Groups 1 to 3, respectively, and the values increased in the order of Groups 1, 2, and 3. The coefficient of variation were 6.41 ± 6.09, 3.29 ± 2.22, and 1.30 ± 1.17, and the test-retest SD were 0.83 ± 0.70, 0.47 ± 0.31, and 0.19 ± 0.17 in Groups 1, 2, and 3, respectively. The coefficient of variation and test-retest SD values decreased in the order of Groups 1, 2, and 3, and showed a significant difference (all, P < 0.05). CONCLUSION: The repeatability of OCTA tended to decrease with a shorter TBUT. When the TBUT is <5 seconds, care must be taken to interpret the OCTA results correctly.

Clinical characteristics and prognosis of Total Rhegmatogenous retinal detachment: a matched case-control study.

BACKGROUND: Although many studies have reported clinical features, surgical outcomes of rhegmatogenous retinal detachment (RRD), studies focusing on total RRD are rare. In this study, we investigate the clinical characteristics, risk factors, and prognosis of total RRD. METHODS: A retrospective chart review was performed on cases of 44 total RRD and an age- and sex-matched 88 partial RRD. Two groups were compared for clinical characteristics, risk factors, and prognosis. RESULTS: The prevalence of total RRD in all cases of retinal detachment was 4.4%. Pseudophakic eye, ocular trauma, and proliferative vitreoretinopathy (PVR) were significantly associated with a risk of total RRD (P = .002, P = .003, and P < .001, respectively). In the total RRD group, retinal breaks were located in both superior and inferior parts of the retina, and macular holes and giant retinal tears were frequently found. The best-corrected visual acuity (log MAR) before surgery and final best-corrected visual acuity after surgery were 2.23 ± 0.45 and 1.88 ± 0.96, which was significantly poorer than in the partial RRD group (P < .001). The success rate after primary surgery was 75.0% in the total RRD group, which was significantly lower than partial RRD group (P < .001). Old age, pseudophakic eye, and macular hole as the type of retinal break were highly associated with low success rate. (P = .010, P = .0500, and P = .002). CONCLUSIONS: Patients with total RRD had higher recurrence rate and poorer visual outcome after surgery than patients with focal RRD. Old age, pseudophakic eye, and presence of macular hole were important risk factors for recurrence after total RRD repair. Additional surgical procedures should be considered to combine with vitrectomy to achieve better surgical outcomes in these patients.

THICKNESSES OF CENTRAL MACULAR, RETINAL NERVE FIBER, AND GANGLION CELL INNER PLEXIFORM LAYERS IN PATIENTS WITH HYPERTENSION.

PURPOSE: To compare retinal thickness between patients with chronic hypertension without retinopathy, hypertensive retinopathy, Keith-Wagener-Barker Grade IV status, and normal controls using spectral domain optical coherence tomography. METHODS: In this retrospective study, we analyzed patients who visited our retinal clinic from January 2013 to February 2016. Of those included, 58 eyes of 58 patients were in the healthy control group (Group A), 37 eyes of 37 patients were in the chronic hypertension without retinopathy group (disease duration of at least 10 years; Group B), and 31 eyes of 31 patients with relieved hypertensive retinopathy (Grade IV hypertensive retinopathy a year or more ago but no longer had hypertensive retinopathy at the time of the study; Group C). The thicknesses of the central macula, retinal nerve fiber layer (RNFL), and ganglion cell inner plexiform layer (GCIPL) were measured by spectral domain optical coherence tomography in each group. RESULTS: The average thicknesses of the central macula, RNFL, and GCIPL layers were lower in Group B than in Group A (P < 0.001, 0.001, and <0.001, respectively). The thicknesses of the three layers were lower in Group C than in Group B (P < 0.001, <0.001, and <0.001, respectively). Of the three groups, the average thicknesses of the central macula, RNFL, and GCIPL were lowest in the Group C (P < 0.001, <0.001, and <0.001, respectively). CONCLUSION: The central macula, RNFL, and GCIPL in Group B were significantly thinner than those of healthy eyes, and these retinal changes were more prominent in Group C. Thus, the effects of retinal changes associated with hypertension should be considered when analyzing the thicknesses of the central macular, RNFL, and GCIPL layers in patients with ocular disorders, including retinal, glaucoma, and neuro-ophthalmological diseases.

PRIMARY CORE VITRECTOMY TECHNIQUE BEFORE CATARACT SURGERY IN COMBINED PHACOVITRECTOMY FOR EYES WITH DENSE VITREOUS HEMORRHAGES.

PURPOSE: To investigate the efficacy and safety of a primary core vitrectomy technique for combined phacovitrectomy in eyes showing a poor red reflex because of dense vitreous hemorrhage before cataract surgery. METHODS: A total of 156 eyes from 156 patients, who underwent combined phacovitrectomy because of cataract and dense vitreous hemorrhage, and who were followed up for at least 6 months were included. The patients were divided into a primary phacoemulsification group (Group A, 80 eyes) who underwent phacoemulsification first followed by total vitrectomy and a primary vitrectomy group (Group B, 76 eyes) who underwent core vitrectomy first followed by cataract surgery and followed by total vitrectomy. A conventional 23-gauge combined phacovitrectomy was performed in all patients. The operation time, including the total continuous curvilinear capsulorhexis time and total cataract surgery time, and the incidence of surgery-related complications were evaluated in the two groups. RESULTS: Diabetic retinopathy was the most common cause for vitreous hemorrhage in both groups (Group A: 51 eyes; Group B: 39 eyes). The total continuous curvilinear capsulorhexis time (P = 0.001) and total cataract surgery time (P = 0.036) were significantly shorter in Group B than in Group A. Among the complications, radial tears occurred more frequently in Group A than Group B, but these differences were not statistically significant (P = 0.211). Pupil size reduction during cataract surgery was greater in Group B than in Group A (P = 0.034). There were no significant differences in posterior capsular ruptures or posterior capsular opacities between the two groups. Other postoperative complications were not observed in either group until 6 months after surgery. CONCLUSION: Primary core vitrectomy combined with phacovitrectomy of patients who had dense vitreous hemorrhage helped to obtain a good red reflex and enabled surgeons to perform successful cataract surgery. In addition, primary core vitrectomy was an easy and safe technique, which reduced the surgery time and surgery-related complications. This surgical technique would, therefore, be helpful to vitreoretinal surgeons.

LONGITUDINAL CHANGES IN THICKNESSES OF THE MACULA, GANGLION CELL-INNER PLEXIFORM LAYER, AND RETINAL NERVE FIBER LAYER AFTER VITRECTOMY: A 12-Month Observational Study.

PURPOSE: To analyze longitudinal changes in the thicknesses of the macula, ganglion cell-inner plexiform layer (GC-IPL), and peripapillary retinal nerve fiber layer (RNFL) after vitrectomy. METHODS: Thirty-eight patients diagnosed with intraocular lens (IOL) dislocation without evidence of other vitreoretinal diseases were included. They underwent conventional vitrectomy and IOL transscleral fixation, with a follow-up of 12 months. Using spectral domain optical coherence tomography, the thicknesses of the macula, GC-IPL, and peripapillary RNFL in the vitrectomized and fellow control eyes were measured. Various optic nerve head parameters were also determined. RESULTS: Optical coherence tomography showed that there were no significant differences in postoperative central macular thickness compared with baseline values. The average GC-IPL thickness increased 1 month after surgery from baseline (P = 0.038). The average RNFL thickness increased from baseline at 1 month (P = 0.001) and 3 months (P = 0.011) after vitrectomy. The mean foveal, GC-IPL, and RNFL thicknesses of the study eyes compared with the fellow control eyes increased at 1 month (P = 0.034), 1 month (P = 0.048), and 1 month (P = 0.013) to 3 months (P = 0.038), respectively, after surgery. However, no significant differences were found in intraocular pressure or optic nerve head parameters between the study and fellow control eyes at 12 months after surgery. CONCLUSION: Transient increases in the thickness of the macula and GC-IPL were observed at 1 month after vitrectomy, and the postoperative RNFL thickness increased until 3 months after surgery, after which it returned to preoperative levels. There was no significant change in intraocular pressure or optic nerve head parameters before and after surgery.

Interocular Asymmetry of the Ganglion Cell-inner Plexiform Layer in Diabetic Retinopathy.

SIGNIFICANCE: The interocular difference in the ganglion cell-inner plexiform layer thickness showed a significant correlation with the diabetic retinopathy (DR) severity. PURPOSE: The purpose of this study was to analyze the interocular differences in the foveal, retinal nerve fiber layer (RNFL), and ganglion cell-inner plexiform layer (GC-IPL) thickness of DR patients using spectral-domain optical coherence tomography. METHODS: A total of 508 eyes from 254 patients with different severities of DR and 184 eyes from 92 control subjects were included. The GC-IPL, foveal, and RNFL thicknesses were measured, and the interocular differences in these thicknesses were correlated in control subjects and DR patients. RESULTS: The interocular difference in the average GC-IPL thickness significantly increased with the severity of DR. The interocular differences in the average GC-IPL thicknesses of the severe nonproliferative DR (NPDR) and the proliferative DR patients were significantly higher than those of the control group. However, there was no significant difference in thickness between the control group and the group with mild to moderate NPDR. In the group with proliferative DR, the interocular difference in the average GC-IPL was greater than those in the central foveal and RNFL thicknesses. Multivariate regression analyses showed that the DR severity and the interocular difference in central foveal thickness were significantly correlated with the interocular difference in the average GC-IPL thickness. CONCLUSIONS: The interocular differences in the central foveal, RNFL, and GC-IPL thicknesses significantly increased with increased DR severity. However, there was no significant difference between the control group and the group with mild to moderate NPDR. The GC-IPL differences showed a significant correlation with DR severity. These findings may be an indicator of DR progression.

Retinal Nerve Fiber Layer Thickness in Various Retinal Diseases.

SIGNIFICANCE: Peripapillary retinal nerve fiber layer (RNFL) thickness measurements may be influenced by the range and severity of lesions that are observed distinctively in each retinal disease. PURPOSE: We investigated the effects of various macular (central serous chorioretinopathy, macular hole, epiretinal membrane, wet age-related macular degeneration) and retinal vascular (branch retinal vein occlusion, central retinal vein occlusion, diabetic macular edema) diseases on peripapillary RNFL thickness measurements using spectral-domain optical coherence tomography. METHODS: Six hundred thirty-one eyes from 464 patients with various retinal diseases and 167 controls of similar age were included in this retrospective study. Using spectral-domain optical coherence tomography, we measured the thickness of the macula and the RNFL in both various retinal disease eyes and normal control eyes. Four sectorial and average RNFL thicknesses were compared between each disease and age-matched control eyes. The macular thicknesses were also compared. RESULTS: In the macular disease group, superior (P = .033) and temporal (P = .024) quadrant RNFL thicknesses of central serous chorioretinopathy and temporal (P < .001) quadrant RNFL thicknesses of epiretinal membrane were greater than the age-matched control eyes. No RNFL measurements in macular hole or wet age-related macular degeneration differed significantly from the controls. In the retinal vascular disease group, all sectorial and average RNFL thicknesses of diabetic macular edema and central retinal vein occlusion were greater than those of the controls (all P < .05). In branch retinal vein occlusion, superior (P = .012) and temporal (P < .001) quadrant RNFL thicknesses were greater than those of the controls. CONCLUSIONS: Peripapillary RNFL thickness measurements may be influenced by the range and severity of lesions that are observed distinctively in each retinal disease. It also appeared that macular disease had a local effect on RNFL thickness, whereas retinal vascular disease had a diffuse effect on RNFL thickness.

Effects of Measurement Center Shift on Ganglion Cell-inner Plexiform Layer Thickness Measurements.

SIGNIFICANCE: Our authors studied the effects of measurement center shift on ganglion cell-inner plexiform layer (GCIPL) thickness measurements in Cirrus spectral-domain optical coherence tomography (SD-OCT). The measurement center shift affects the GCIPL thickness measurement depending on the distance of shift. PURPOSE: The purpose of this study was to explore changes in macular GCIPL thicknesses measurements after manual shifting of the measurement center using SD-OCT. METHODS: A prospective study was conducted. A total of 30 normal eyes of 30 subjects were included in the study. An experienced examiner obtained two consecutive measurements of GCIPL thickness using SD-OCT. Coefficients of repeatability were calculated for the average, minimum, and sectoral (superotemporal, superior, superonasal, inferonasal, inferior, and inferotemporal) thicknesses. Next, the measurement center was manually shifted from the foveal center. Three measurement centers were horizontally placed at 59-µm intervals from the foveal center, and two further centers were placed 176 µm apart. Also, three measurement centers were vertically placed at 47-µm intervals from the foveal center, and two further centers were placed 142 µm apart. The thickness of GCIPL was measured again at each shift point, and the changes of thickness before and after movement were analyzed. RESULTS: When the measurement centers were shifted to positions 59 µm horizontally or 47 µm vertically from the fovea, no significant changes in GCIPL thicknesses were evident. However, upon more pronounced shifting, the average GCIPL thickness of the direction of the shift region was significantly lower than baseline, whereas the GCIPL of the diametrically opposite sector was thicker than baseline. CONCLUSIONS: The impact of changes associated with shifting of the measurement center should be taken into consideration when measuring GCIPL thickness in patients with retinal diseases, glaucoma, or neuro-ophthalmological conditions.

The effect of center point shift on the measurement of macular thickness: a spectral domain-optical coherence tomography study.

PURPOSE: To evaluate the effect of spectral domain-optical coherence tomography (SD-OCT) measurement center shift on the measurement of macular thickness. METHODS: This was a prospective observational case series. A total of 60 normal eyes of 60 subjects included in the study. SD-OCT macular scanning (macular cube 512 × 128 scan) was performed twice by an experienced examiner. The average retinal thicknesses of the nine macular sectors as defined by the Early Treatment Diabetic Retinopathy Study (ETDRS) were recorded. Each coefficient of repeatability was calculated for the macular thickness measurements of the ETDRS subfields. Thereafter, the measurement center was manually decentered to a seven scan point, each from the central fovea in steps of 58.7 µm horizontally and 47.2 µm vertically. At each shift point, the change in the macular thickness was compared. RESULTS: When the displacement distance between the measurement center point and the foveal center was within 117.4 µm horizontally and 141.6 µm vertically, the macular thickness measurements did not show any significant differences. However, if the offset of the EDTRS grid center from the anatomic fovea exceeded, we noted that the thickness at the fovea increased and the opposite-direction region at the inner circle was significantly thinner than the displaced point. CONCLUSIONS: The effect of measurement center shift needs to be considered when analyzing the macular thickness measurements in various ophthalmologic diseases.

PREVENTING PUPILLARY CAPTURE AFTER VITRECTOMY AND TRANSSCLERAL FIXATION OF AN INTRAOCULAR LENS: Iridotomy Using a Vitrectomy Probe.

PURPOSE: To investigate the effects of concurrent iridotomy using a vitreous cutter probe on the prevention of pupillary capture in patients undergoing transscleral fixation of intraocular lens implantation. METHODS: A total of 79 eyes from 79 patients, who underwent transscleral fixation of intraocular lens without preexisting vitreoretinal disorders and who were followed up for 6 months were included. Subjects were divided into a noniridotomy group (51 eyes) and an iridotomy group (28 eyes). After conventional 23-gauge vitrectomy and transscleral fixation of intraocular lens implantation in all patients, 28 patients underwent concurrent iridotomy intraoperatively. The patients were followed up to evaluate the incidence of surgery-related complications, including pupillary capture. RESULTS: There were no statistically significant differences in the preoperative demographic findings between the two groups (all P > 0.05). There was a significant difference in pupillary capture in 15 eyes (29.4%) of the noniridotomy group, compared with 1 eye (3.6%) of the iridotomy group (P = 0.007). There were no differences in postoperative best-corrected visual acuity between the two groups, and no iridotomy-related complications were observed. CONCLUSION: Concurrent iridotomy using a vitreous cutter probe is an easy, rapid, and effective procedure to prevent possible pupillary capture after combined vitrectomy and transscleral fixation of intraocular lens implantation.

Short-Term Visual Acuity and Intraocular Pressure Changes and Their Correlation after Anti-Vascular Endothelial Growth Factor Injection.

PURPOSE: To assess the effect of intravitreal anti-vascular endothelial growth factor injection on short-term changes in intraocular pressure (IOP) and visual acuity (VA) and the correlation between the two values. METHODS: This study included 25 eyes of 25 patients undergoing intravitreal injection of bevacizumab (IVB) with preinjection uncorrected VA (UCVA) >20/40. IOP and UCVA were measured before injection and 1, 5, 10, 15, 20, 25, and 30 min after injection, using a Tono-Pen (Reichert, Chicago, Ill., USA). The IOP and VA values before and after injection were compared. The correlation between IOP and VA at each time point was analyzed. RESULTS: The preinjection IOP value (17.7 mm Hg) increased sharply to 43.1 mm Hg 1 min after injection, followed by a decrease to 30.4, 24.6, 20.7, 18.7, 18.2, and 17.7 mm Hg at 5, 10, 15, 20, 25, and 30 min, respectively. The preinjection UCVA value (0.21; logMAR) increased to 0.96 one minute after injection, followed by a decrease to 0.61, 0.44, 0.33, 0.27, 0.23, and 0.22 at 5, 10, 15, 20, 25, and 30 min, respectively. Significant differences were evident between the preinjection IOP and VA values and those observed over the 5- to 25-min period after injection (p < 0.05). The correlation between IOP and VA was significant 1, 5, and 10 min after injection [p < 0.001 (1 min), p = 0.033 (5 min), and p = 0.002 (10 min)]. CONCLUSIONS: Differences in all IOP and VA values were significant up to 25 min after IVB, compared with preinjection values; however, no significant difference was found 30 min after injection. Such fluctuations in VA and IOP were positively correlated. The patients' own knowledge of VA fluctuations after injection may provide ophthalmologists with sufficient evidence to make an indirect clinical judgment regarding short-term complications of intravitreal injection.

Effects of Retinal Angiography on Optical Coherence Tomography Measurements.

PURPOSE: To evaluate the effects of retinal angiography, using fluorescein and indocyanine green dyes, on optical coherence tomography (OCT) measurements. METHODS: In total, 76 eyes from 76 consecutive patients were included. Macular cube 512 × 128 combination scanning and optic disc 200 × 200 scanning using spectral-domain (SD)-OCT were performed twice, before and after retinal angiography, with fluorescein or indocyanine green. Signal strength, regional retinal thickness of the 9 Early Treatment Diabetic Retinopathy Study subfields, total macular volume, and retinal nerve fiber layer thickness obtained before and after angiography were compared. Repeatability was also investigated. RESULTS: Comparing the results of OCT measured before and after retinal angiography, there was no statistically significant difference in any parameter assessed. The interclass correlation values for each measurement were all >0.808 (range 0.808-0.999). CONCLUSION: Retinal angiography using fluorescein and indocyanine green dyes has no significant effect on OCT measurements.

Diurnal Variation in Choroidal and Retinal Thickness of the Early Treatment of Diabetic Retinopathy Study Macular Subfields Determined Using Swept-Source Optical Coherence Tomography.

PURPOSE: To describe diurnal variation in choroidal thickness (CT) and retinal thickness (RT) of the nine Early Treatment of Diabetic Retinopathy Study (ETDRS) macular subfields determined using swept-source optical coherence tomography. METHODS: A prospective study was conducted on 24 healthy Korean volunteers who underwent two sequential measurements of a randomly selected eye at 9 a.m., 1 p.m., and 6 p.m. The radial scan mode was used. To determine the repeatability and reliability, we applied intragrader agreement using the intraclass correlation coefficient (ICC). RESULTS: Significant diurnal variation in CT was observed. The highest mean CT was found at 9 a.m. The lowest mean CT occurred at 1 p.m. There was excellent intragrader agreement, with the ICC ranging from 0.961 to 0.997. There was no significant diurnal variation in RT. CONCLUSION: There was significant diurnal variation in CT. The choroid was thinner at 1 p.m. than at 9 a.m. and 6 p.m.

Effects of Topical Anti-Glaucoma Medications on Outcomes of Endoscopic Dacryocystorhinostomy: Comparison with Age- and Sex-Matched Controls.

BACKGROUND: This study analyzed the effects of topical anti-glaucoma medications on the surgical outcomes of endoscopic dacryocystorhinostomy (EDCR) in nasolacrimal duct obstruction (NLDO). METHODS: This retrospective study included patients who underwent EDCR for NLDO between September 2012 and April 2021. Thirty patients with topical anti-glaucoma medications and 90 age- and sex-matched controls were included. RESULTS: The success rate of EDCR was higher in the control group than in the anti-glaucoma group (97.8% vs. 86.7%, p = 0.034). Univariate and multivariate logistic regression analyses identified prostaglandin analogs as the most influential risk factor for EDCR success among anti-glaucoma medication ingredients (p = 0.005). The success rate of the group containing all four anti-glaucoma medication ingredients was statistically significant (p = 0.010). The success rate was significantly different in the group of patients who used anti-glaucoma medication for >24 months (p = 0.019). When multiplying the number of drug ingredients by the duration in months, the group > 69 showed a significantly decreased success rate (p = 0.022). Multivariate logistic regression analysis identified the number of anti-glaucoma medications as the most significant risk factor for EDCR success (odds ratio, 0.437; 95% confidence interval, 0.247 to 0.772; p = 0.004). CONCLUSIONS: The authors suggest that the anti-glaucoma medications might cause NLDO and increase the failure rate after EDCR. Therefore, when performing EDCR in patients using topical anti-glaucoma medications, surgeons should consider the possibility of increased recurrence after EDCR in clinical outcomes.

Vertical asymmetry analysis of the macular microvasculature in epiretinal membrane patients with open-angle glaucoma.

To identify the usefulness of vertical asymmetry analysis of the retinal microvasculature in epiretinal membrane (ERM) patients accompanied by open-angle glaucoma (OAG). Subjects were divided into three groups: normal controls (group 1), patients with ERM (group 2), and patients with both ERM and OAG (group 3). Retinal nerve fiber layer (pRNFL) and ganglion cell-inner plexiform layer (GC-IPL) thicknesses, vessel density (VD), and the absolute vertical difference of pRNFL (vdRNFL), GC-IPL (vdGC-IPL), and VD (vdVD) were compared among groups. Logistic regression analysis was performed to determine the factors associated with OAG. Diagnostic accuracy based on the area under the curve (AUC) was conducted. The VD of the full area was 20.9 ± 1.2, 20.0 ± 1.9, and 18.8 ± 2.2 mm-1 (P < 0.001) for groups 1, 2, and 3, respectively. The vdVD differed significantly between group 2 and group 3 (P < 0.001), whereas vdRNFL (P = 0.531) and vdGC-IPL (P = 0.818) did not show a significant difference. Multivariate logistic analyses showed that average pRNFL thickness (OR 0.924, P = 0.001) and vdVD (OR 5.673, P < 0.001) were significant factors associated with OAG in ERM patients. The AUC of the vdVD was 0.81 (95% CI 0.72-0.89), and the combination of average pRNFL thickness and vdVD had the highest AUC (0.87; 95% CI 0.78-0.95; P < 0.001). ERM patients with OAG had a significantly thinner pRNFL thickness, lower macular VD, and higher vdVD than those without OAG. Average pRNFL thickness and vdVD were significant factors associated with OAG in patients with ERM. Additionally, the combination of average pRNFL thickness and vdVD showed good diagnostic performance for OAG in patients with ERM.

Analyses of the ratio of ganglion cell-inner plexiform layer thickness to vessel density according to age in healthy eyes.

PURPOSE: To identify how the inner retinal layer and microvasculature change with age by analyzing the relationships of ganglion cell-inner plexiform layer (GC-IPL) thickness, vessel density (VD), and the ratio of these measurements with age in healthy eyes. METHODS: Participants were divided into five groups according to age. The GC-IPL thickness, VD, and GC-IPL/VD ratio were compared among the groups. Linear regression analyses were performed to identify relationships of GC-IPL/VD ratio with age. RESULTS: The average GC-IPL thicknesses were 84.84 ± 5.28, 84.22 ± 5.30, 85.20 ± 6.29, 83.29 ± 7.06, and 82.26 ± 5.62 µm in the 20s, 30s, 40s, 50s, and 60s age groups, respectively. The VDs were 20.94 ± 1.50, 21.06 ± 1.50, 20.99 ± 1.03, 20.71 ± 0.93, and 19.74 ± 1.73 mm-1 in the 20s, 30s, 40s, 50s, and 60s age groups, respectively. The GC-IPL/VD ratio was 4.05, 4.00, 4.06, 4.02, and 4.17 in each group, respectively, and the ratio of the 60s age group was significantly higher than that of other groups. In linear regression analyses, the GC-IPL/VD ratio was significantly associated with age in the participants aged ≥ 50 years (B = 0.014, P = 0.013), whereas it was not in the participants aged < 50 years (B = 0.003, P = 0.434). CONCLUSIONS: GC-IPL thickness and macular VD showed a tendency to decrease beginning in the 50s age group and the GC-IPL/VD ratio was significantly increased in the 60s age group. Additionally, the GC-IPL/VD ratio was positively associated with age in subjects aged ≥ 50 years, which implies a more pronounced decline over time in VD rather than GC-IPL thickness.

The Ganglion Cell-Inner Plexiform Layer Thickness/Vessel Density of Superficial Vascular Plexus Ratio According to the Progression of Diabetic Retinopathy.

Purpose: The purpose of this study was to identify the relationship between the gangion cell-inner plexiform layer (GC-IPL) and retinal vasculature in the context of the progression of diabetic retinopathy (DR). Methods: The subjects were divided into four groups according to DR stage: normal controls (group 1), patients with diabetes mellitus (DM) without DR (group 2), patients with mild or moderate nonprogressive DR (NPDR; group 3), and patients with severe NPDR (group 4). GC-IPL thickness, vessel density of superficial vascular plexus (SVD), and the GC-IPL/SVD ratio were compared among the groups. Results: A total of 556 eyes were enrolled; 288 in group 1, 140 in group 2, 76 in group 3, and 52 in group 4. The mean GC-IPL thicknesses were 83.57 ± 7.35, 82.74 ± 7.22, 81.33 ± 6.74, and 79.89 ± 9.16 µm in each group, respectively (P = 0.006). The mean SVDs were 20.40 ± 1.26, 19.70 ± 1.56, 18.86 ± 2.04, and 17.82 ± 2.04 mm-1 in each group, respectively (P < 0.001). The GC-IPL/SVD ratios were 4.11 ± 0.38, 4.22 ± 0.40, 4.36 ± 0.54, and 4.54 ± 0.55 in each group, respectively (P < 0.001). In Pearson's correlation analysis, DR stage was significantly correlated with the GC-IPL/SVD ratio (coefficient = 0.301; P < 0.001). Conclusions: As the DR stage progressed, the GC-IPL thickness tended to decrease, with the macular SVD showing a significant reduction. Additionally, the impairment of retinal vasculature was more prominent than GC-IPL thinning as DR progressed, which suggests that retinal vasculature changes may precede diabetic retinal neurodegeneration.

Effect of Weiss ring on peripapillary retinal nerve fiber layer thickness measurements using SD-OCT.

Spectral-domain optical coherence tomography (SD-OCT) must accurately identify and measure the peripapillary retinal nerve fiber layer (pRNFL) thickness to improve the repeatability and reproducibility, and reduce measurement errors. Because Weiss ring can be located in front of the optic disc, we hypothesized that it may affect pRNFL thickness measurements obtained using SD-OCT. We retrospectively reviewed the medical records of patients with (group W) and without (group N) Weiss ring, observed on OCT fundus image and an RNFL map devised using SD-OCT. Optic disc cube scans (200 × 200) were obtained to measure pRNFL thicknesses (superior, temporal, inferior, nasal, and average) at two consecutive visits. Pearson's correlation coefficient (r), intraclass correlation coefficient (ICC), and coefficient of variation (CV) were calculated. The r and ICC values for the pRNFL thickness measurements at the two visits were lower for group W compared to group N, but statistical significance was reached only for inferior pRNFL thickness. In addition, CV values were greater for group W compared to group N, but the differences were significant only for inferior and average pRNFL thickness measurements (p < 0.001 and p = 0.004, respectively). Weiss ring located near the optic disc can affect pRNFL thickness measurements and repeatability thereof, especially the inferior quadrant and average values. Therefore, it is important to identify the presence of Weiss ring when analyzing pRNFL thickness values.

Retinal nerve fibre layer/ganglion cell-inner plexiform layer thickness ratio in patients with systemic hypertension.

PURPOSE: Acute and chronic hypertension may have different pathophysiological mechanisms in the retina. Here, we compared the retinal nerve fibre layer (RNFL)/ganglion cell-inner plexiform layer (GC-IPL) thickness ratios of patients with 'relieved' severe hypertensive retinopathy (relieved HTNR) and chronic hypertension without retinopathy (chronic HTN) to those of normal controls. METHODS: We performed cross-sectional study. The eyes were divided into the following groups: normal controls (Group A, age ≥50 years; Group D, age <50 years); chronic HTN (Group B, <10 years of HTN; TNHT; Group C, ≥10 years of HTN); and relieved HTNR (previously diagnosed with grade IV HTNR and relieved retinopathy for >1 year; Group E), and the RNFL/GC-IPL thickness ratio was compared among Groups A-C and between Groups D and E. RESULTS: A total of 379 eyes were included in this study. Groups A-E consisted of 145, 59, 63, 60 and 52 eyes, respectively. The RNFL/GC-IPL thickness ratios were 1.161 ± 0.093, 1.158 ± 0.082 and 1.162 ± 0.089 in groups A-C, respectively, and did not showed a statistically difference (p = 0.966). The RNFL/GC-IPL thickness ratio of groups D and E were 1.169 ± 0.080 and 1.221 ± 0.080, respectively, and showed a statistically difference (p = 0.001). CONCLUSIONS: The RNFL/GC-IPL thickness ratios of the chronic HTN group did not show a difference compared with the normal controls. However, relieved HTNR patients showed a higher ratio than the normal controls. Physicians should be aware that acute hypertensive injury could affect the RNFL/GC-IPL thickness ratio.