Animals ; Macaca mulatta ; Optic Disk ; Glaucoma ; Craniocerebral Trauma ; Intraocular Pressure ; Low Tension Glaucoma

BACKGROUND: Normal tension glaucoma (NTG) is a less pressure-dependent type of glaucoma with characteristic optic neuropathy. Recently, the biomechanical mechanism has been thought to account for glaucomatous optic neuropathy to some degree. We intended to compare dynamic corneal response parameters (DCRs) among patients with primary open-angle glaucoma with normal tension or hypertension and controls. The correlations between DCRs and known risk factors for glaucoma were also analyzed. METHODS: In this cross-sectional study, 49 NTG subjects, 45 hypertension glaucoma (HTG) subjects, and 50 control subjects were enrolled. We compared the differences in DCRs using corneal visualization Scheimpflug technology among the NTG, HTG, and control groups. We also analyzed the correlations between DCRs and known risk factors for glaucoma (eg, central corneal thickness [CCT], intraocular pressure [IOP], etc). RESULTS: The maximum inverse concave radius (NTG: 0.18 [0.17, 0.20] mm-1; control: 0.17 [0.16, 0.18] mm-1; P = 0.033), deformation amplitude ratio of 2 mm (DAR 2 mm, NTG: 4.87 [4.33, 5.39]; control: 4.37 [4.07, 4.88]; P < 0.001), and DAR 1 mm (NTG: 1.62 [1.58, 1.65]; control: 1.58 [1.54, 1.61]; P < 0.001) were significantly higher in NTG than in the controls. The integrated radius (IR, NTG: 8.40 ± 1.07 mm-1; HTG: 7.64 ± 1.31 mm-1; P = 0.026) and DAR 2 mm (NTG: 4.87 [4.33, 5.39]; HTG: 4.44 [4.12, 5.02]; P < 0.007) were significantly higher, whereas the stiffness parameter at the first applanation (SP-A1, NTG: 91.23 [77.45, 107.45]; HTG: 102.36 [85.77, 125.12]; P = 0.007) was lower in NTG than in HTG. There were no significant differences in the DCRs between HTG and control groups (P > 0.05). In the univariate and multivariate analyses, some of the DCRs, such as IR, were negatively correlated with CCT and IOP, whereas SP-A1 was positively correlated with CCT and IOP. CONCLUSIONS The cornea was more deformable in NTG than in HTG or controls. There were no significant differences in corneal deformability between HTG and controls. The cornea was more deformable with the thinner cornea and lower IOP.
Biomechanical Phenomena ; Cornea ; Cross-Sectional Studies ; Glaucoma, Open-Angle ; Humans ; Hypertension ; Intraocular Pressure ; Low Tension Glaucoma

PURPOSE: To investigate the effect of a visual field (VF) test on intraocular pressure (IOP) and relevant parameters in a normal group and an open-angle glaucoma group, and to determine the appropriate time of IOP measurements.METHODS: The IOP was measured by a rebound tonometer before and after a VF test for the normal, normal-tension glaucoma, and high-tension glaucoma groups, and IOP differences after the VF tests were compared among groups. Parameters including age, sex, axial length, central corneal thickness, IOP before the VF test, the VF index, mean deviation, VF test duration, and usage of IOP lowering medications were investigated, and the correlations of these parameters with IOP changes after VF tests were determined using linear regression analyses.RESULTS: A total of 232 participants (232 eyes) included 55 normal subjects, 131 normal-tension glaucoma patients, and 46 high-tension glaucoma patients. The IOP differences after VF tests were not statistically significant in the normal and high-tension glaucoma groups, and the difference was 0.31 mmHg in the normal-tension glaucoma group (p = 0.013). Multivariate regression analyses revealed that axial length (p = 0.005) and IOP before the VF test (p < 0.001) were relevant factors in the total number of patients, and the axial length (p = 0.017), IOP before the VF test (p = 0.001), and duration (p = 0.029) were found to be significantly associated with IOP differences in the normal-tension glaucoma group.CONCLUSIONS: The IOP changes after VF tests using the rebound tonometer were significant in the normal-tension glaucoma group, but were within an acceptable range. The IOP value measured after a VF test is clinically valid in clinical practice.
Glaucoma ; Glaucoma, Open-Angle ; Humans ; Intraocular Pressure ; Linear Models ; Low Tension Glaucoma ; Visual Field Tests ; Visual Fields

PURPOSE: The purpose of this study was to investigate the association between normal-tension glaucoma (NTG) and allergic rhinitis in a population-based setting using data from the Korea National Health and Nutrition Exam Survey (2010–2012). METHODS: The authors selected a total of 8,614 participants aged 40 years and older for this study. All participants completed an ophthalmic examination required for diagnosis of NTG based on the International Society for Geographical and Epidemiological Ophthalmology criteria. An interview regarding nasal symptoms was also performed. The included participants were classified into NTG (n = 604) and control (n = 8,010) groups. The authors compared the groups in terms of prevalence of allergic rhinitis and identified risk factors of NTG. RESULTS: In NTG patients, allergic rhinitis prevalence was 29.1% (176/604), which was significantly higher than that of the control group (25.0%, 2,000/8,010; p = 0.023). There were significant associations between NTG and allergic rhinitis (odds ratio [OR]= 1.34, 95% confidence interval [CI] = 1.12–1.62, p = 0.002), even after adjusting for potential confounders (age, sex, diabetes, hypertension, number, of family members, household income quartile, frequency of eating out, and smoking status). In particular, patients with NTG aged 60–69 years, those aged 70–79 years, and those who were male had significantly higher ORs for prior allergic rhinitis compared with control subjects (OR = 1.62, 95% CI = 1.16–2.26, p = 0.005; OR = 1.52, 95% CI = 1.06–2.18, p = 0.024; and OR = 1.42, 95% CI = 1.10–1.83, p = 0.007, respectively). CONCLUSIONS: This study showed a significant association between NTG incidence and allergic rhinitis, especially in males and elderly patients (>60 years of age). These results suggested that allergic rhinitis may have a potential role in the development of NTG. Therefore, ophthalmologists and allergic rhinitis patients should remain vigilant to this potential risk factor.
Aged ; Diagnosis ; Eating ; Family Characteristics ; Glaucoma ; Humans ; Hypertension ; Incidence ; Korea ; Low Tension Glaucoma ; Male ; Ophthalmology ; Prevalence ; Rhinitis, Allergic ; Risk Factors ; Smoke ; Smoking

PURPOSE: This study evaluated the efficacy and safety of a brinzolamide 1%-brimonidine 0.2% fixed combination (BBFC) for normal tension glaucoma (NTG) in a South Korean population. METHODS: This study included 45 patients who were newly diagnosed with NTG and treated with BBFC as the first therapy from January 2016 through December 2016. The unilateral eye of NTG eyes of all patients were enrolled. If both eyes were eligible, the eye with the more severe glaucomatous change was selected. If the glaucomatous change was similar in both eyes, the right eye was selected. The patients received the BBFC twice a day. Diurnal intraocular pressure (IOP) was measured every 2 and 1/2 hours between 09:00 am and 04:30 pm. The IOP change with respect to body position (positional IOP) was measured at baseline and at 6 months after eyedrop instillation. Throughout the study, all side effects were recorded and monitored by the investigators. RESULTS: Ten patients were excluded due to an allergic reaction or follow-up loss. A total of 35 patients were enrolled in this study. The mean IOP was 15.32 ± 4.00 mmHg at baseline and 13.38 ± 3.30 mmHg at 6 months after BBFC instillation (p < 0.001). The IOP fluctuation decreased from 3.33 ± 3.10 to 2.35 ± 1.40 mmHg after BBFC instillation; however, the difference was not statistically significant (p = 0.150). The mean change in positional IOP showed a statistically significant reduction from 16.94 ± 3.18 to 14.80 ± 3.27 mmHg (p = 0.025). There was no serious adverse drug reaction except in three cases of allergic reaction. CONCLUSIONS: BBFC is effective for the reduction of mean IOP and positional IOP in NTG patients.
Drug-Related Side Effects and Adverse Reactions ; Follow-Up Studies ; Humans ; Hypersensitivity ; Intraocular Pressure ; Low Tension Glaucoma ; Research Personnel ; Treatment Outcome

PURPOSE: This study evaluated the effect of a fixed combination of 0.0015% tafluprost-0.5% timolol (Tapcom®, Santen, Osaka, Japan) in glaucoma patients. METHODS: This study included 23 patients who were diagnosed with normal tension glaucoma and treated with a fixed combination of 0.0015% tafluprost-0.5% timolol as the first therapy. Diurnal intraocular pressure (IOP) was measured every 2 and 0.5 hours between 9:00 am and 4:30 pm. The IOP change with respect to body position (positional IOP) was measured at baseline and at 6 months after eye-drop instillations. IOP fluctuation was defined as the standard deviation of IOP measurements. Throughout the study, all side effects were recorded and monitored by the investigators. RESULTS: The mean reduction in IOP in the 0.0015% tafluprost-0.5% timolol fixed combination-treated eyes was −3.37 ± 2.39 mmHg (−19.70 ± 13.97%) for the right eye and −3.22 ± 2.27 mmHg (-18.81 ± 13.28%) for the left eye (paired t-test, p < 0.001). The mean positional IOP measured at 4 pm at 6 months after 0.0015% tafluprost-0.5% timolol fixed combination instillation showed statistically significant reduction from the mean positional IOP at baseline. There was a significant difference in the number of patients with ≤3 mmHg IOP variation over four time points between baseline and at 6 months in the 0.0015% tafluprost-0.5% timolol fixed combination-treated eyes (McNemar test, p < 0.001). There was no serious adverse event causing ocular damage. CONCLUSIONS: Use of 0.0015% tafluprost-0.5% timolol fixed combination was effective and well tolerated in reducing IOP and in maintaining its effectiveness in glaucoma patients.
Glaucoma ; Humans ; Intraocular Pressure ; Low Tension Glaucoma ; Research Personnel ; Timolol

PURPOSE: To investigate the association between corneal biomechanical properties and initial visual field defect pattern in normal tension glaucoma using an Ocular Response Analyzer (ORA; Reichert Instruments, Depew, NY, USA). METHODS: Forty-one patients with normal tension glaucoma were divided into 2 subgroups, 21 patients with initial paracentral scotomas and 20 patients with initial peripheral scotomas. The corneal biomechanical properties of corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg), corneal-compensated IOP (IOPcc) measured by the ORA, central corneal thickness, and Goldmann applanation tonometry were comparatively analyzed between the 2 groups. RESULTS: The patients with initial peripheral scotomas were significantly younger than those with initial paracentral scotomas (49.45 ± 13.33 years vs. 58.14 ± 12.49 years, p = 0.035) and showed more myopia (− 2.42 ± 2.22 diopter vs. − 0.89 ± 2.22 diopter, p = 0.034). The mean CRF was significantly lower in the initial paracentral scotoma group than in the initial peripheral scotoma group. (9.45 ± 1.95 mmHg vs. 10.58 ± 2.05 mmHg; p = 0.041). No significant difference in CH, IOPg, or IOPcc was seen between the groups. CONCLUSIONS: CRF was significantly different between the initial paracentral scotoma group and initial peripheral scotoma group in normal tension glaucoma. Thus, CRF may be useful to predict initial central field loss in normal tension glaucoma.
Humans ; Intraocular Pressure ; Low Tension Glaucoma* ; Manometry ; Myopia ; Scotoma ; Visual Fields*

PURPOSE: To analyze the effect of stereopsis and contrast sensitivity on the quality of life and to evaluate the relationship between integrated binocular visual field (IVF) and binocular visual function in bilateral normal tension glaucoma (NTG) patients. METHODS: Stereopsis and contrast sensitivity tests were performed and compared among 44 NTG patients and 32 normal subjects. The IVF was integrated using the best location method. The correlation between visual function and subscales of the National Eye Institute Visual Function Questionnaire 25 (NEI VFQ-25) was evaluated using univariate linear regression. RESULTS: Stereopsis and contrast sensitivity for the bilateral NTG patients were decreased compared to the normal controls. Stereopsis and contrast sensitivity exhibited a significant correlation with social functions related to vision and color vision among subscales of NEI VFQ-25. IVF mean deviation (MD) and better eye MD showed a significant correlation with stereopsis and contrast sensitivity, while worse eye MD showed no association. CONCLUSIONS: Deterioration of stereopsis and contrast sensitivity in NTG patients affects their quality of life related to social functions and color vision. Both IVF and better eye MDs are correlated with stereopsis and contrast sensitivity in NTG patients.
Color Vision ; Contrast Sensitivity ; Depth Perception ; Humans ; Linear Models ; Low Tension Glaucoma* ; Methods ; National Eye Institute (U.S.) ; Quality of Life* ; Telescopes* ; Visual Fields

BACKGROUNDHigh intraocular pressure (IOP) and low central corneal thickness (CCT) are important validated risk factors for glaucoma, and some studies also have suggested that eyes with more deformable corneas may be in higher risk of the development and worsening of glaucoma. In the present study, we aimed to evaluate the association between corneal biomechanical parameters and asymmetric visual field (VF) damage using a Corvis-ST device in patients with untreated normal tension glaucoma (NTG).

METHODSIn this observational, cross-sectional study, 44 newly diagnosed NTG patients were enrolled. Of these, 31 had asymmetric VF damage, which was defined as a 5-point difference between the eyes according to the Advanced Glaucoma Intervention Study scoring system. Corneal biomechanical parameters were obtained using a Corvis-ST device, such as time from start until the first and second applanation is reached (time A1 and time A2, respectively), cord length of the first and second applanation (length A1 and length A2, respectively), corneal speed during the first and second applanation (velocity A1 and velocity A2, respectively), time from start until highest concavity is reached (time HC), maximum amplitude at the apex of highest concavity (def ampl HC), distance between the two peaks at highest concavity (peak dist HC), and central concave curvature at its highest concavity (radius HC).

RESULTSTime A1 (7.19 ± 0.28 vs. 7.37 ± 0.41 ms, P = 0.010), length A1 (1.73 [1.70-1.76] vs. 1.78 [1.76-1.79] mm, P = 0.007), length A2 (1.58 [1.46-1.70] vs. 1.84 [1.76-1.92] mm, P< 0.001), peak dist HC (3.53 [3.08-4.00] vs. 4.33 [3.92-4.74] mm, P = 0.010), and radius HC (6.20 ± 0.69 vs. 6.59 ± 1.18 mm, P = 0.032) were significantly lower in the worse eyes than in the better eyes, whereas velocity A1 and def ampl HC were significantly higher (0.156 [0.149-0.163] vs. 0.145 [0.138-0.152] m/s, P = 0.002 and 1.19 ± 0.13 vs. 1.15 ± 0.13 mm, P = 0.005, respectively). There was no significant difference in time A2, velocity A2, and time HC between the two groups. In addition, no difference was observed in IOP, CCT, and axial length. In the univariate and multivariate analyses, some of the Corvis-ST parameters, including time A1 and def ampl HC, were correlated with known risk factors for glaucoma, and there was also a significant positive correlation between def ampl HC and age.

CONCLUSIONSThere were differences in dynamic corneal response parameters but not IOP or CCT between the paired eyes of NTG patients with asymmetric VF damage. We suggest that the shape of the cornea is more easily altered in the worse eyes of asymmetric NTG patients.

Aged ; Biomechanical Phenomena ; physiology ; Cornea ; metabolism ; physiology ; Cross-Sectional Studies ; Female ; Glaucoma ; metabolism ; physiopathology ; Humans ; Intraocular Pressure ; physiology ; Low Tension Glaucoma ; metabolism ; physiopathology ; Male ; Middle Aged ; Multivariate Analysis ; Prospective Studies ; Visual Fields ; physiology

PURPOSE: To evaluate the association between body mass index (BMI) and visual field (VF) progression in normal tension glaucoma (NTG) patients. METHODS: We reviewed the medical records of 78 eyes of 78 NTG patients who were treated with eye drops for more than 18 months. Age, sex, existence of hypertension (HTN), diabetes mellitus (DM), refractive error, baseline intraocular pressure (IOP), IOP reduction ratio, baseline VF indices including mean deviation (MD) and pattern standard deviation, VF progression rate (MD slope, dB/year), number of eye drops, and BMI were analyzed. The progression of VF was determined by glaucoma change probability analyses (STATPAC 2) using a Humphrey field analyzer. RESULTS: The mean follow-up in consecutive eyes was 4.4 ± 2.7 years. A total of 18 eyes showed progression and 60 eyes did not. The VF progression rate (p < 0.001) and number of eye drops (p = 0.024) showed statistical differences, but age, sex, existence of HTN and DM, refractive error, baseline IOP, IOP reduction ratio, baseline VF index, and BMI did not show a statistical difference between the two groups (all, p > 0.05). However, multiple linear regression analyses showed that a lower BMI was significantly associated with faster VF progression in the progression group (β = 0.078; standard error = 0.030; p = 0.027). CONCLUSIONS: In the group in which VF loss progressed despite treatment with eye drops, a lower BMI was associated with progression of VF loss in NTG patients.
Body Mass Index* ; Diabetes Mellitus ; Follow-Up Studies ; Glaucoma ; Humans ; Hypertension ; Intraocular Pressure ; Linear Models ; Low Tension Glaucoma* ; Medical Records ; Obesity ; Ophthalmic Solutions ; Refractive Errors ; Visual Fields*