Long-Term (>8 Years) Evaluation of Progression in Patients with Low-Pressure Glaucoma

Incidence of Glaucoma Progression and Rate of Visual Field Deterioration in a Cohort of Urban Ghanaians

PRCIS

The annual incidence of glaucoma progression (9.7%) and rates of visual field mean deviation (MD) change in progressors (-1.02±0.06 dB/y) are high in a small cohort of urban Ghanaians.

PURPOSE

To report the incidence of glaucoma progression and the rate of visual field deterioration in a small cohort of Ghanaians.

METHODS

One hundred ten subjects (204 eyes) diagnosed with glaucoma at a baseline population-based screening examination were re-examined a mean of 8.3±0.8 years later. Eyes were classified as having progressed if the optic disc alone, visual field alone or both showed significant glaucomatous changes on follow-up. Visual field MD was used to calculate the rate of visual field progression.

RESULTS

Progression was observed in 89 (80.9%, 9.7%/year) subjects (130 eyes). Progression occurred in 32 (31.7%, 3.8%/year) subjects by optic disc alone (46 eyes), 38 (44.7%, 5.4%/year) subjects by visual field alone (58 eyes), and 19 (25.0%, 3.0%/year) subjects by both modalities (26 eyes). The average rate of change in MD differed significantly between progressors (-1.02±1.06 dB/y) and nonprogressors (+0.089±0.49 dB/y), P =0.001. The rate of visual field worsening was greater among those who were classified as having progressed by both structure and function (-1.29±0.68 dB/y) and by function alone (-1.21±1.20 dB/y) than by structure alone (-0.55±0.76 dB/y). Progression was significantly associated with older age [odds ratio (OR), 1.42; P <0.001] and higher baseline intraocular pressure (OR, 1.18; P =0.002). Factors associated with rate of MD change were baseline older age (OR, 1.66; P =0.003), higher intraocular pressure (OR, 2.81; P =0.007), better visual field MD (OR, 1.41; P =0.004), and systemic hypertension (OR, 1.15; P =0.029).

CONCLUSION

The incidence and rate of visual field progression are high in this longitudinal study of Ghanaian subjects with glaucoma. The findings may have important clinical and public health policy ramifications.

Hydrogen sulfide supplement preserves mitochondrial function of retinal ganglion cell in a rat glaucoma model

Glaucoma is a neurodegenerative disease of visual system characterized by gradual loss of retinal ganglion cells (RGC). Since mitochondrial dysfunction of RGC is significantly involved in the pathological mechanisms of glaucoma, and hydrogen sulfide (H₂S) takes part in the pathogeny of glaucoma and shows promising potential in restoring mitochondrial function in other neurons, the authors aimed to investigate the impact of H₂S on mitochondrial function of RGC with a rat glaucoma model. An established chronic ocular hypertension (COH) rat model induced by injection of cross-linking hydrogel into anterior chamber was adopted, and a H₂S donor, sodium hydrosulfide (NaHS), was selected to treat rats through intraperitoneal injection. After a period of 4 weeks, RGCs were isolated from the subjected rats with an immunopanning method and went through evaluations of mitochondrial membrane potential (MMP), mitochondrial permeability transition pore (MPTP) opening, intracellular Ca2 + level, reactive oxygen species (ROS) level, and cytosolic Cytochrome C distribution. The results showed that the mitochondrial function of RGC in experimental glaucoma was markedly improved by H₂S supplement, being presented as stabilization of MMP, alleviation of MPTP opening, improvement of intracellular Ca²⁺ hemostasis, reduction of ROS accumulation, and inhibition of Cytochrome C release. Our study implicated that preservation of mitochondrial function by H₂S probably plays a key role in protecting RGC in the context of glaucomatous neuropathy, and it is worth further deepgoing research to benefit the development of glaucoma treatment.

Stratification-Based Investigation of Adjunctive Brimonidine or Timolol to a Prostaglandin Analogue in Japanese Patients with Normal-Tension Glaucoma

Purpose

We previously investigated the efficacy and safety of adding 0.1% brimonidine (Brim) or 0.5% timolol (Tim) to prostaglandin analogue (PGA) monotherapy to treat patients with normal-tension glaucoma (NTG) with intraocular pressure (IOP) of ≤16 mmHg. Herein, we describe an additional post-hoc stratifying analysis of the possible differences in the effect of IOP-lowering and pulse rate (PR) after adjunctive Brim or Tim to PGA.

Patients and Methods

This study included 128 subjects. Patients with NTG treated with PGA were stratified based on their baseline IOP. The changes in IOP from baseline and the effect of patient factors on IOP changes were investigated. Patients were stratified by age for investigation of their PR and blood pressure (BP). The change and the effect of patient factors on PR and BP were investigated.

Results

After stratification analysis, in 52 eyes treated with Brim and 61 eyes with Tim with baseline IOP 12 ≤ IOP ≤ 16 mmHg, both eye drops lowered IOP significantly (P < 0.0001), and the IOP-lowering efficacy of Brim was non-inferior to that of Tim. However, in 9 Brim- and 6 Tim-treated eyes with baseline IOP of <12 mmHg, no statistically significant decrease in IOP was evident with either eye drop. In the Tim group, PR decreased significantly (P < 0.05) after stratification by age.

Conclusion

The IOP-lowering efficacy of Brim was non-inferior to that of Tim after stratification by baseline IOP (12 ≤ IOP ≤ 16 mmHg). The discrepancy in the IOP-lowering effects of Brim and Tim observed in the previous study was thought to be related to enrolled subjects with low baseline IOP. PR decreased significantly in the Tim group even after age stratification. PR should be considered when selecting β-blockers for glaucoma treatment.

Combined Ab interno viscocanaloplasty (ABiC) in open-angle glaucoma: 12-month outcomes

PURPOSE

The aim of this study was to analyse the safety profile and efficacy of ab interno viscocanaloplasty (ABiC) through to 12 months post-operatively.

METHODS

In this retrospective study, the medical records of all patients who underwent ABiC between September 2015 and December 2019 were analysed. Complete success was defined as a 12-month reduction in intraocular pressure (IOP) ≥ 20% from baseline with no concomitant medications. Qualified success criteria were identical, with no more medications than at baseline.

RESULTS

In all, 54 eyes of 41 patients were analysed. Mean IOP decreased from 23.6 ± 7.4 mmHg preoperatively to 14.2 ± 2.9 mmHg (-39.8%; p < 0.001) after 12 months. Concomitantly, the number of anti-glaucoma treatment dropped from 2.9 ± 1.0 to 0.6 ± 1.1 (-79.3%; p < 0.001). Amongst patients with a baseline MD < -12.0 dBs, mean IOP decreased from 22.8 ± 9.8 mmHg to 13.8 ± 4.4 mmHg (p = 0.049), with a concomitant reduction of medications from 2.8 ± 1.3 to 1.2 ± 1.3 (p < 0.001). Complete success at 12 months was achieved in 46% of eyes, and qualified success was achieved in 65% of eyes. Amongst eyes with a baseline MD < -12.0 dBs, 50% achieved complete success, and 83.3% achieved qualified success. A total of 19 eyes (35.2%) were considered surgical failure, all due to uncontrolled IOP. Of them, 7 eyes (13.0%) required further filtering surgery. Twelve post-operative adverse events were observed, with early post-operative IOP spikes being the most common (22.2%).

CONCLUSIONS

ABIC achieved a statistically significant reduction in IOP and anti-glaucoma medications through 12 months, while maintaining a favourable safety profile in mild-to-severe open-angle glaucoma.

Evidence-based understanding of disc hemorrhage in glaucoma

Disc hemorrhage is a characteristic finding that is highly associated with glaucoma development or progression. Consequently, the literature commonly designates disc hemorrhage as a "risk factor" for glaucoma progression; however, the exact cause-and-effect relationship or mechanism remains unclear. In this review, we discuss the emerging evidence that disc hemorrhage is a secondary development that follows glaucomatous damage. As our understanding of disc hemorrhage has progressed in recent decades, we suggest the terminology be changed from "risk factor" to "indicator" of ongoing glaucomatous development or progression for a more accurate description, better indication of the clinical implications and, ultimately, a better guide for future research.

The influence of central corneal thickness on progression of normotensive glaucoma

OBJECTIVES

To verify whether there is a relation between central corneal thickness (CCT) and progression of normotensive glaucoma (NTG), to assess the impact of early changes in the visual field on their progression in time.

METHODS AND PATIENTS

The sample consisted of two groups of patients with NTG. In the first group there were 50 eyes of 25 persons (15 females and 10 males) average age 63 years who had been treated with prostaglandins. The second group consisted of 50 eyes of 25 persons (16 females and 9 males) average age of 62 years who had had no local therapy. All patients were cardiologically compensated and had no other internal or neurological disease. Visual acuity was 1.0 with a possible correction (less than ±3 dioptres) in all patients. The IOP ranged between 10-15 mmHg in all patients. If hypotensive ophthalmological therapy was initiated, it had been stable for the last five years. In all patients, we monitored CCT, excavation in the papilla (c/d), pattern defect (PD) and overall defect (OD) of the visual field. In 2013, changes in the visual fields were approximately the same in all patients. We compared the results of the visual fields after five years, i.e. the results were obtained in 2018. CCT was measured, using the ultrasound pachymeter Tomey SP-100. PD and OD of the visual field using the glaucoma fast threshold program with the MEDMONT M 700 device. For statistical comparison, we used the paired t test and correlation analysis.

RESULTS

In both groups, we found progression of PD in time (P=0.0000, P=0.0001, respectively). In the patients treated with prostaglandins, OD had not statistically significantly changed (P=0.49) in contrast to the untreated patients (P=0.001). There was no statistically significant relation between CCT and PD in any of the groups. It was similar between the CCT and OD. In the treated NTG patients, we found a weak correlation between the changes in PD in time (r=0.2846, P=0.0438) and moderately strong relation for OD (r=-0.63). The finding was similar in untreated patients PD (r=-0.2, P=0.162) and OD (r=-0.443, P=0.001).

CONCLUSION

We found no relationship between progression of changes in the visual fields in CCT. Progression of changes in the visual fields was higher in patients who had more advanced changes at the beginning of observation. The untreated patients had progression of changes in the visual fields both in PD and OD in contrast to those who were taking prostaglandins and presented changes only in PD.

The impact of disc hemorrhage studies on our understanding of glaucoma: a systematic review 50 years after the rediscovery of disc hemorrhage

PURPOSE OF REVIEW

To trace the influence of disc hemorrhage studies on our understanding of glaucoma.

SOURCES

Major articles published during the last 50 years since the rediscovery of disc hemorrhage were identified. A total of 196 articles were selected from 435 articles retrieved using the keywords glaucoma and disc hemorrhage as of August 9 2018 from PubMed.

RECENT FINDINGS

The main characteristics of disc hemorrhage, including its morphology, recurrence rate, duration, increased incidence in glaucoma, and role in the progression of normal tension glaucoma was well understood by the year 2000. Since then, studies have focused on more sophisticated and accurate methods of elucidating both structural and functional progression, with special attention to the role of the lamina cribrosa. Nevertheless, both the mechanism of disc hemorrhage development and its fuller relationship with glaucoma remain unclear. Disc hemorrhage research requires careful study of glaucomatous optic neuropathy. This has been facilitated by recent advances in optical coherence tomography (OCT) angiography and other OCT technologies. Furthermore, animal studies of disc hemorrhage promise new insights into glaucomatous optic neuropathy.

Effect of quantitative intraocular pressure reduction on visual field defect progression in normal tension glaucoma under medical therapy applying Markov model

Purpose

To quantitatively evaluate the association of intraocular pressure (IOP) reduction with visual field defect (VFD) progression in normal tension glaucoma (NTG) under medical therapy.

Patients and methods

Clinical data for 622 eyes of 311 primary open-angle glaucoma and NTG patients were collected from April 2006 to March 2016. Of these patients, those with normal IOP, glaucomatous VFD by Anderson’s criteria, corrected visual acuity ≥0.7, >5 years of medical therapy, ≥5 visual field tests at least five times at 12-month intervals, visual field testing reliability coefficients of ≤33%, and mean deviation (MD) exceeding below −20 dB in the initial visual field test were included in this retrospective data analysis. MD and IOP data were collected at baseline and after 5 years. Following MD categorization into stages I to IV, stage transition matrices were generated using a Markov model to evaluate VFD changes. Eyes were divided based on IOP reduction (0%, 10%, 15%, 20%, 25%, 30%) from baseline. VFD aggravations were compared using the Markov model and MD slopes with IOP reduction rates as cutoff values.

Results

Overall, 132 eyes of 132 NTG patients fulfilled the eligibility criteria. MD decreased significantly (P<0.0001) at 5 years vs baseline. During follow-up, visual field stage using the Markov model was constant in ~60%, with transitions in ~40%. IOP decreased significantly (P>0.001) at 5 years vs baseline. Though MD slopes did not differ significantly between each of the groups that achieved the various IOP reduction cut-off values and the corresponding group that did not achieve the cut-off values, a significant difference (P=0.0432) in VFD was found between the group that achieved the 25% cut-off value and the group that did not when evaluated using the Markov model.

Conclusion

In NTG patients, VFD aggravation was significantly suppressed in groups with IOP reductions of ≥25% from baseline.

Visual Subfield Progression in Glaucoma Subtypes

Purpose

To investigate visual field progression pattern and factors associated with progression in patients with primary open-angle glaucoma (POAG), normal-tension glaucoma (NTG), and chronic angle-closure glaucoma (CACG).

Methods

The raw data of the 30-2 Humphrey Field Analyzer from glaucoma patients with definite visual field progression were processed with pointwise linear regression (PLR) analysis. The rate of change of retinal threshold sensitivity in the ten glaucoma hemifield test (GHT) zones, the upper and the lower hemifields, and the whole field was evaluated and was correlated with patients' basic demographic data.

Results

An average follow-up of 6.94 ± 2.69 years that showed the rate of change of visual field threshold sensitivity was correlated with the peak posttreatment intraocular pressure (IOP) and the long-term IOP fluctuations in all GHT zones except in the inferior arcuate area. The baseline IOP, the trough posttreatment IOP, the refractive status, and the CCT were not correlated with VF progression.

Conclusion

The rate of visual field progression was correlated with the peak posttreatment IOP and the long-term IOP fluctuation but with subfield differences.

Low nocturnal diastolic ocular perfusion pressure as a risk factor for NTG progression: a 5-year prospective study

OBJECTIVE

To assess the relationship between baseline intraocular pressure (IOP), blood pressure (BP) and ocular perfusion pressure (OPP), and the 5-year visual field progression in normal-tension glaucoma (NTG) patients.

DESIGN

Prospective, longitudinal study.

METHODS

Sixty-five NTG patients who were followed up for 5 years are included in this study. All the enrolled patients underwent baseline 24-h IOP and BP monitoring via 2-hourly measurements in their habitual position and were followed up for over 5 years with reliable VF tests. Modified Anderson criteria were used to assess VF progression. Univariable and multivariable analyses using Cox's proportional hazards model were used to identify the systemic and clinical risk factors that predict progression. Kaplan-Meier survival analyses were used to compare the time elapsed to confirmed VF progression in the presence or absence of each potential risk factor.

RESULTS

At 5-year follow-up, 35.4% of the enrolled patients demonstrated visual field progression. There were statistically significant differences in the mean diastolic blood pressure (p < 0.05) and diastolic OPP (p < 0.05) between the progressing and the non-progressing group. There was no association between IOP parameters and NTG progression. Multivariable analysis identified low nocturnal DOPP at baseline as a significant predictive risk factor for glaucomatous visual field progression at 5 years. An mmHg decrease in nocturnal DOPP increases the hazard of progression by 1.4 times. Patients with DOPP < 35 mmHg have 2.3-fold higher probability of progressing compared to the patients with DOPP > 43.7 mmHg (log rank = 0.018).

CONCLUSION

Diastolic parameters of BP and OPP were significantly lower in the NTG patients who progressed after 5 years. Low nocturnal DOPP is an independent predictor of glaucomatous visual field progression in NTG patients.

Long-term progression of visual field defects and related factors in medically treated normal tension glaucoma

Purpose

To analyze factors related to long-term progression of visual field defects (VFD) in patients with normal tension glaucoma (NTG) under medical therapy.

Patients and methods

Clinical data from 622 eyes of 311 primary open-angle glaucoma and NTG patients were collected from April 2006 to March 2016. Of these patients, those with normal intraocular pressure (IOP); glaucomatous VFD judged by Anderson’s criteria; corrected visual acuity ≥0.7; receiving more than 6 years medical therapy; having undergone ≥10 visual field tests performed at 6-month intervals using a Humphrey field analyzer (Swedish Interactive Threshold Algorithms standard, C 24-2 program); and having reliability coefficients of visual field testing <33% and mean deviation (MD) more than −20 decibels in the initial visual field test were included in data analysis. The relationship between MD slope deterioration at final observation and consecutive decreases in MD value during the observation period, as well as clinical characteristics and IOP-related factors, were analyzed.

Results

Of 134 eyes in 134 NTG patients meeting all eligibility criteria, significant MD slope deterioration was observed in 80 eyes (59.7%). MD slope deterioration was significantly associated with consecutive decreases in MD values (Cochran–Armitage trend test: P=0.0000; univariate logistic regression analysis: P<0.0001). While no significant relationship was observed between central corneal thickness, refractive error, or prevalence of disc hemorrhage, consecutive decreases in MD value was significantly related to MD slope deterioration (univariate logistic regression analysis: P<0.0001). A reduction of IOP during the follow-up period was significantly related to nondeterioration of the MD slope (multivariate logistic regression analysis: P=0.0020).

Conclusion

In this 6-year observation of NTG patients treated with medical therapy, the occurrence of three or more consecutive decreases in MD value was significantly associated with visual field deterioration. Reduction in IOP was postulated to be contributing in the prevention of VFD progression.

Hydrogen sulfide supplement attenuates the apoptosis of retinal ganglion cells in experimental glaucoma

Glaucoma is a group of neurodegenerative eye diseases characterized by progressive impairment of visual function due to loss of retinal ganglion cells (RGC). As hydrogen sulfide (H₂S) was reported to play a role in the process of glaucomatous neuropathy and improve RGC survival in experimental glaucoma, the authors aimed to investigate the anti-apoptosis effect of H₂S supplement in a rat glaucoma model, and further tried to explore the involved factors in the neuroprotection. A chronic ocular hypertension (COH) rat model induced by intracameral injection of cross-linking hydrogel was employed to simulate glaucoma and 288 rats were subjected to experimental procedures in the present study. After 4 weeks of sodium hydrosulfide (NaHS) administration following COH induction, the apoptosis of RGC isolated from experimented rats as well as apoptosis of neurons in ganglion cell layer (GCL), intrinsic apoptotic pathway activity, mitochondrial function, glial activation, NF-κB pathway activity, NADPH oxidase activity, autophagy activity and TNF-α level in retina were evaluated. The results showed that H₂S supplement effectively attenuated the apoptosis of RGC in experimental glaucoma, and the neuroprotection by H₂S might correlate with preservation of mitochondrial function, attenuation of oxidative stress, suppression of glial activation, inhibition of inflammatory pathways and downregulation of autophagy. Our study indicated that H₂S supplement resulted in significant neuroprotection through attenuation of RGC apoptosis which might be linked with multiple factors in experimental glaucoma. The new therapeutic strategy might potentially contribute to benefit glaucoma treatment, which is worth further concerns.