Factors Predicting Successful Selective Laser Trabeculoplasty to Prevent Glaucoma Progression to Surgery

Purpose@#To investigate the factors predicting successful selective laser trabeculoplasty (SLT) to prevent glaucoma progression to surgery in patients whose intraocular pressure (IOP) is not controlled with medications. @*Methods@#This retrospective chart review included 102 eyes of 92 glaucoma patients who underwent SLT between 2018 and 2020. Success was defined as the prevention of glaucoma surgery for at least 1 year with an IOP less than 21 mmHg or no progression of retinal nerve fiber layer thinning. Kaplan-Meier survival analysis and the Cox proportional hazard model were used for the analysis. @*Results@#A low pretreatment IOP, good visual acuity, and a smaller visual field defect were significantly correlated with success. When the other eye underwent glaucoma surgery or its SLT treatment failed, the success rate of SLT was lower. As the pretreatment IOP increased by 1 mmHg, the SLT failure rate increased by 1,376 times and when the SLT for the other eye failed, it increased by 19,577 times. When the mean deviation of the visual field increased by 1 decibel (dB), the SLT failure rate decreased by 0.928 times (p < 0.05). @*Conclusions@#SLT is more effective in early glaucoma patients with an IOP lower than 25 mmHg, smaller visual field defect, and good visual acuity to prevent glaucoma progression to surgery.

Risk Factors for Requiring Glaucoma Surgery in Steroid-induced Glaucoma

Purpose@#To study the risk factors for steroid-induced glaucoma patients requiring glaucoma surgery, despite being fully treated with medications and laser trabeculoplasty. @*Methods@#The charts of 50 eyes diagnosed with steroid-induced glaucoma from January 2012 to December 2015 were reviewed retrospectively. 28 eyes required surgery and 22 eyes were successfully treated with medications and laser trabeculoplasty. The demographic information as well as ocular parameters, presence of ocular/systemic comorbidities, and past history of steroid use were evaluated to determine the risk factors associated with the need for glaucoma surgery. @*Results@#For the 7 factors that were statistically significant by univariate regression analysis, multivariate regression analysis showed that the average retinal nerve fiber layer thickness and duration of steroid use were not statistically significant (p = 0.876 and p = 0.068, respectively), whereas age and initial intraocular pressure were only statistically significant in some of the analysis models (p = 0.040-0.278, p = 0.016-0.201, respectively). Myopia, vertical cup-to-disc ratio, and systemic comorbidities had statistically significant correlations (p = 0.019, p = 0.011-0.03, p = 0.022, respectively) with surgical decision by multivariate regression analysis. @*Conclusions@#The risk factors for requiring glaucoma surgery in steroid-induced glaucoma patients were young age, myopia, initial optic nerve damage, systemic disease (systemic lupus erythematosus, rheumatoid arthritis, and atopy), and duration of steroid use. These results may be helpful in predicting the prognosis of patients with steroid-induced glaucoma and in screening for patients who require a more aggressive treatment at the time of disease presentation.

Comparison of Retinal Ganglion Cell Damage in Glaucoma and Retinal Vein Occlusion by Visual Field

PURPOSE: We analyzed and compared retinal ganglion cell damage between patients with glaucoma and those with branched retinal vein occlusion (BRVO). We performed two types of visual field examinations. METHODS: We retrospectively reviewed the medical records of 40 glaucoma eyes and 40 BRVO eyes. We compared the median deviation (MD), the pattern standard deviation (PSD), and sensitivity of damaged visual hemifield from frequency-doubling technology (FDT) C24-2 and standard automated perimetry (SAP) C24-2 visual field tests evaluation. We sought correlations between the MDs and retinal nerve fiber layer thickness as revealed by optical coherence tomography. RESULTS: MDs did not differ between the groups. PSD value was higher in glaucoma patients with FDT C24-2 test (p = 0.022), but no difference between two groups with SAP C24-2 test (p = 0.144). In terms of the sensitivity of the damaged visual hemifield, glaucoma patients had larger areas of damage in the FDT C24-2 test (p < 0.01). In regression analyses, the log R2 values of both tests were higher in glaucoma patients. CONCLUSIONS: Glaucoma patients had a greater damaged visual field area in the FDT C24-2 test than the SAP C24-2 test. The BRVO patients exhibited similar extents of damage in both tests. Thus, the subtypes and distributions of damaged retinal ganglion cells may differ between the conditions, facilitating differential diagnosis.

Associations between Retinal Nerve Fiber Layer Defect and Systemic Indices According to the KNHNES 2010–2012

PURPOSE: To investigate the associations between retinal nerve fiber layer (RNFL) defects and systemic factors in the Korean population. METHODS: Based on data from the 5th Korean National Health and Nutritional Examination Survey (2010–2012), 2,999 non-glaucomatous patients and 424 glaucoma patients were included. We compared body mass index (BMI), blood pressure, and blood test values according to the presence and location of RNFL defects in the groups and analyzed whether these defects were associated with various underlying diseases. RESULTS: In the non-glaucomatous group, RNFL defects were significantly and linearly related with BMI (p = 0.035), systolic blood pressure (p < 0.001), diastolic blood pressure (p = 0.018), fasting blood glucose (p < 0.001), HbA1c (p < 0.001), serum ferritin (p = 0.008), and RNFL defects were also significantly associated with diabetes mellitus (p = 0.001), hypertension (p < 0.001), dyslipidemia (p = 0.003), a history of myocardial infarction or angina (p = 0.037), and migraines (p = 0.004). In the glaucoma group, patients who had superior RNFL defects had a significantly lower systolic blood pressure (p = 0.034) than patients who had inferior RNFL defects. The other systemic indices did not differ significantly between these two subgroups. Superior RNFL defects were significantly associated with diabetes mellitus (p = 0.047) and a history of cerebrovascular accident (p = 0.031). CONCLUSIONS: RNFL defects in both the non-glaucomatous and glaucoma groups were associated with systemic factors. We could identify that the possibility of RNFL defects can be deduced from these systemic abnormalities and active treatment is needed in abnormal systemic condition.

Effects of Early Postoperative Intraocular Pressure after Ahmed Glaucoma Valve Implantation on Long-term Surgical Outcomes

PURPOSE: To evaluate the long-term effects of early postoperative intraocular pressure (IOP) after Ahmed glaucoma valve (AGV) implantation on long-term surgical outcomes. METHODS: This retrospective, non-randomized study included 100 eyes of 100 patients who underwent AGV surgery. We divided the enrolled patients into four groups according to the presence of transient hypotony within the first postoperative week or the presence of a hypertensive phase during the first three postoperative months. Postoperative IOP, the number of glaucoma medications, and cumulative success rate were compared among the groups. RESULTS: There was significantly better IOP control and a better success rate in the non-hypertensive phase group 2 years postoperatively. However, no significant difference was found in the IOP or success rate at 2 years postoperatively between the transient hypotony and non-hypotony groups. Further subgroup analysis showed that the non-hypotony, non-hypertensive phase group had a significantly higher success rate (100%) at 2 years postoperatively. CONCLUSIONS: We can predict the long-term prognosis after AGV implantation by considering the early postoperative IOP state and the presence of a hypertensive phase.

Features of the Lamina Cribrosa and the Autonomic Nervous System in Glaucoma Patients with Disc Hemorrhages

PURPOSE: To assess the effects of structural changes in the lamina cribrosa (LC) and the status of the autonomic nervous system on disc hemorrhages (DHs). METHODS: A retrospective study was performed on 68 eyes of 68 patients with primary open-angle glaucoma and optic DHs. We divided the patients into two groups using optical coherence tomography according to the presence of LC defects, and then compared both groups. We also analyzed autonomic nervous system function using the heart rate variability test, and compared the two groups. RESULTS: Eyes with LC defects had significantly longer axial lengths than those without defects (p = 0.029), and the DH was located more proximally (p < 0.001). A significantly larger proportion of eyes without LC defects had configurational optic disc changes such as optic disc rim notching, focal rim thinning, or generalized thinning (p = 0.001). On heart rate variability testing, the group without LC defects had a significantly higher “low frequency/high frequency ratio” than the group with defects (p = 0.008). CONCLUSIONS: There was a difference in the clinical features of DH between eyes with and without LC defects. Eyes with LC defects were more myopic and the proximal part of the DH tended to be on the disc cup or characterized by peripapillary atrophy. These results suggest that the DH developed due to a mechanical cause in eyes with LC defects. Patients without LC defects had a more dysregulated autonomic nervous system. The DH location was related to disc rim notching and neural rim losses, which implies ischemia as the pathogenic mechanism involved in the development of DH in eyes without LC defects. Therefore, more careful observations of the LC would facilitate a better understanding of the specific pathogenic mechanisms underlying DH.

The Correlations between Recurrent Disc Hemorrhage and Sympathetic Variability, and the Disc Morphology

PURPOSE: To evaluate the correlations of sympathetic variability and recurrent disc hemorrhage, and the morphology of the optic disc. METHODS: This study included 41 eyes of 41 patients who had at least one disc hemorrhage (DH), who were diagnosed with open-angle glaucoma or suspected glaucoma. All eyes had a DH at presentation and were followed-up for at least 3 years. Eyes were classified by the morphology of the optic disc into the focal rim thinning, concentric cupping, or myopic disc groups. The variability of the sympathetic nervous system was defined by the Standard deviation of all node to node intervals (SDNN) as very low frequency, low frequency (LF), or high frequency, which was the standard parameter of heart rate variabilities. RESULTS: There were 14 (34.14%) eyes with a single DH, and the remaining eyes with a recurrent DH. Single DH patients tended to have a myopic disc (p < 0.001) and, especially in the lower 50% of the SDNN group, the recurrent DH group had a lower SDNN (p = 0.046), and a higher LF (p = 0.002). CONCLUSIONS: DH recurred when patients had morphological glaucomatous changes, especially focal rim thinning. Differences of the sympathetic variability had a strong correlation with the recurrent DH.

Comparison of the Variability of Standard Automated Perimetry between Preperimetric Glaucoma Patients and Normal Controls

PURPOSE: To compare the variability of standard automated perimetry (SAP) between patients with preperimetric glaucoma (PPG) and normal controls. METHODS: This study included 67 eyes, classified into the following groups: 30 eyes, normal controls; and 37 eyes, PPG. All subjects were examined with 24-2 Humphrey static perimetry. The visual field was divided into superonasal, superotemporal, inferonasal, and inferotemporal sectors. The variability of SAP was obtained using the standard deviation of sensitivity points at each location. We compared the variability of SAP between the normal controls and PPG patients. RESULTS: The variability of SAP was higher in the PPG group compared with the normal control group (p < 0.001). There was also a significant correlation between the variability of SAP and intraocular pressure fluctuations and retinal nerve fiber layer thickness (both p < 0.05). The variability of SAP in the PPG group was higher (p < 0.05) in all areas except the inferotemporal sector compared with the normal control group. CONCLUSIONS: The variability of the SAP increased in PPG patients compared with normal controls, even when the visual field test results were normal.

The Effectiveness of Visual Field C10-2 in the Early Detection of Glaucoma with Parafoveal Scotoma

PURPOSE: To identify the correspondence between the central sensitivity of several visual field (VF) tests and ganglion cell inner plexiform layer (GC-IPL) thickness in early glaucoma patients with parafoveal scotoma. METHODS: Fifty-seven eyes from 57 patients with glaucomatous optic neuropathy and parafoveal scotoma were analyzed using the standard automated perimetry (SAP) C10-2 test, the SAP C24-2 test, and the frequency doubling technology perimetry (FDT) C24-2 test. The correlation between the VF central sensitivity and the GC-IPL thickness from macular scans via optical coherence tomography was analyzed. RESULTS: The central sensitivity was 27.51 ± 5.43 dB, 27.39 ± 5.05 dB, and 22.09 ± 5.08 dB for SAP C24-2, SAP C10-2, and FDT C24-2, respectively. Mean GC-IPL thickness was 70.2 ± 8.5 µm. Using regression analysis, the value of log R² between the logarithmic central sensitivity and GC-IPL thickness was 0.498, and the linear R2 between the antilogarithmic central sensitivity and GC-IPL thickness in SAP C10-2 was 0.486, and both were statistically significant (p < 0.05). This relationship was stronger in early glaucoma patients compared to late glaucoma patients using SAP C10-2. CONCLUSIONS: The structure-function relationship between GC-IPL thickness and central sensitivity was better with SAP C10-2, especially in early glaucoma patients, compared to other VF modalities.

Cases of Pseudophakic Pseudoexfoliation in Glaucoma Patients

We present cases of primary open angle glaucoma patients without previous history of pseudoexfoliation who developed pseudoexfoliative materials on the anterior surface of the intraocular lens after cataract surgery. Among 5 unilateral pseudophakic pseudoexfoliation cases, 3 showed a more advanced state of glaucoma in the affected eye. The other 2 cases showed progression of glaucoma in the affected eye after the development of pseudophakic pseudoexfoliation, while the unaffected eyes remained stable. In the latter 2 cases, control of intraocular pressure was difficult, and more glaucoma medication was needed in the affected eye. Pseudophakic pseudoexfoliation in glaucoma patients with no history of pseudoexfoliation syndrome or pseudoexfoliative glaucoma has not been reported. In our cases, the eyes which developed pseudophakic pseudoexfoliation showed a more advanced state of glaucoma, more difficulty controlling intraocular pressure, and faster progression of glaucoma. More observation is needed, but we cautiously postulate that pseudophakic pseudoexfoliation may have a role as a clinical risk factor in the prediction of glaucoma progression.