Optic disc drusen in patients diagnosed with normal tension glaucoma.

PURPOSE: To investigate the prevalence of optic disc drusen (ODD) and optic nerve head (ONH) morphology in patients diagnosed with normal tension glaucoma (NTG). METHODS: In this prospective cross-sectional study, we included patients diagnosed with NTG from two glaucoma units. In both eyes, dense enhanced depth imaging optical coherence tomography volume scans of the ONH by means of standardized scanning guidelines were performed to examine for presence of ODD, and radial ONH scans were used for investigating parameters such as scleral canal diameter, cup/disc ratio and cup depth. RESULTS: We found ODD in 7 (3.6%) of 195 eyes, in 6 (6.1%) out of 98 patients diagnosed with NTG. The ODD were not ophthalmoscopically visible in five out of six patients. Eyes with ODD had lower cup/disc ratio, 0.44 ± 0.4 (p = 0.040), and less-prominent cup depth, 236.6 ± 204.4 µm (p = 0.041) compared to eyes without ODD, 0.81 ± 0.2 and 437.8 ± 139.1 µm, respectively. We found no significant difference in scleral canal diameter between the eyes without (1602.8 ± 193 µm) and those with ODD (1492 ± 123.4 µm, p = 0.057). CONCLUSION: The prevalence of ODD in patients diagnosed with NTG is substantially higher than in the background population. A low cup/disc ratio correlates with ODD presence. Therefore, due to the challenges associated with NTG diagnosis, we recommend examining the deep layers of the ONH in NTG patients with a cup/disc ratio lower than 0.5 to avoid misdiagnosing ODD as NTG.

Prospective evaluation of the comorbidity of obstructive sleep apnea in patients with glaucoma.

STUDY OBJECTIVES: This study aimed to identify prospectively the correlation between obstructive sleep apnea (OSA) severity, ocular microcirculation changes, and visual function changes in patients with glaucoma. METHODS: We prospectively enrolled patients with glaucoma who were willing to undergo overnight polysomnography. The enrolled patients were further divided into normal tension glaucoma, high-tension glaucoma, and control. Visual field progression was analyzed using sequential standard automated perimetry. Peripapillary and macular vessel density were assessed through optical coherence tomography angiography (OCT-angiography). The associations between polysomnography parameters, OCT-angiography parameters, and visual field progression were analyzed. RESULTS: A total of 22 patients with normal tension glaucoma, 30 patients with high-tension glaucoma, and 24 control patients were enrolled. Through regression analysis, glaucoma was found to be an independent predictor of moderate-to-severe OSA (P = .035); furthermore, moderate-to-severe OSA was significantly associated with visual field progression (P = .008 in the high-tension glaucoma subgroup and P = .008 in the overall glaucoma). Additionally, OSA severity was negatively correlated with the ganglion cell complex thinning rate in the normal tension glaucoma subgroup. CONCLUSIONS: Presence of glaucoma increased the risk of moderate-to-severe OSA compared with the control group. OSA severity was related to visual field deterioration in patients with glaucoma and further associated with structural progression in the normal tension glaucoma subgroup. Careful monitoring of the comorbid OSA status of patients with glaucoma is essential to prevent disease progression. CITATION: Chan Y-H, Chuang L-H, Yu C-C, et al. Prospective evaluation of the comorbidity of obstructive sleep apnea in patients with glaucoma. J Clin Sleep Med. 2022;18(1):47-56.

Clinical Profiles of Glaucomatous Patients With High-tension and Low-tension Optic Disc Hemorrhages: A Comparative Study.

PRCIS: Patients with low-tension optic disc hemorrhages (DHs) are more frequently women, have a diagnosis of normal-tension glaucoma (NTG) diagnosis and greater visual field (VF) loss. Symptoms of vascular dysregulation and Asian race also seem to be more prevalent in this clinical subtype. PURPOSE: Optic DH is an important glaucoma risk factor, and occurs in a wide intraocular pressure (IOP) range. We sought to characterize distinct clinical subtypes of patients with high-tension disc hemorrhage (HTDH) and low-tension disc hemorrhage (LTDH). PATIENTS AND METHODS: In this cross-sectional study, treated glaucomatous patients with DHs from 2 glaucoma services were consecutively enrolled. Disc photographs were evaluated for the presence of DH by 2 glaucoma specialists. After inclusion, patients were classified on HTDH (IOP≥16 mm Hg) and LTDH (IOP<16 mm Hg; median split). Clinical and ocular data from the time of DH detection were compared between groups. RESULTS: One hundred thirty-three DH patients were included (LTDH=66 eyes; HTDH=67 eyes). Patients with LTDH were more often women than those with HTDH (77% vs. 42%; P=0.030). There was also a trend for a higher prevalence of Asian descendants (24% vs. 9%; P=0.058) and symptoms suggestive of vascular dysregulation (34% vs. 14%; P=0.057) in LTDH patients. Eyes with LTDH also had worse VF mean deviation index (P=0.037), higher prevalence of NTG diagnosis (46% vs. 17%; P<0.001), and tended to have thinner central corneas (P=0.066). CONCLUSIONS: Patients developing DHs with treated IOPs in the low teens seem to more frequently fit in a profile represented by women, NTG diagnosis and greater VF loss. The presence of symptoms suggestive of vascular dysregulation and race also seem to differ between these 2 clinical subtypes. A closer optic disc surveillance is recommended for patients with the LTDH subtype, as they may develop DHs despite seemingly well-controlled IOP.

Multiple Systemic Vascular Risk Factors Are Associated With Low-Tension Glaucoma.

PRCIS: Multiple systemic vascular-associated conditions including systemic hypertension and hypotension, diabetes mellitus, migraine headache, peripheral vascular disease, Raynaud syndrome, and anemia were associated with low-tension glaucoma. PURPOSE: The purpose of this study was to identify systemic risk factors associated with low-tension glaucoma. PATIENTS AND METHODS: A retrospective case-control study design was employed to identify patients seen at the Mayo Clinic Department of Ophthalmology between 2005 and 2015 with low-tension glaucoma and an age-matched and sex-matched control group, each containing 277 patients. RESULTS: The low-tension glaucoma group had more myopic refractive errors (-1.6 vs. -1.0 D, P<0.001), lower intraocular pressure (14.2 vs. 15.2 mm Hg, P<0.001), and a higher cup-to-disc ratio (0.7 vs. 0.3, P<0.001). The low-tension glaucoma group was significantly less likely to be obese (body mass index >30, P=0.03). This group had a significantly higher prevalence of systemic hypertension [odds ratio (OR): 1.64, P=0.004], diabetes mellitus (OR: 3.01, P<0.001), peripheral vascular disease (OR: 2.61, P=0.009), migraine headache (OR: 2.12, P=0.02), anemia (OR: 2.18, P=0.003), systemic hypotension (OR: 4.43, P<0.001), Raynaud syndrome (OR: 3.09, P=0.05), and angiotensin-converting enzyme inhibitor (OR: 1.64, P=0.01) or calcium channel blocker use (OR: 1.98, P=0.004). After adjusting for systemic hypertension, calcium channel blocker use remained significant (OR: 1.70, P=0.03). No significant difference was found between groups with respect to hyperlipidemia, obstructive sleep apnea, coronary artery disease, carotid stenosis, stroke, or statin, angiotensin-converting enzyme inhibitor, angiotensin receptor blocker, beta-blocker, or metformin use. CONCLUSIONS: Multiple vascular-associated conditions were associated with low-tension glaucoma including systemic hypertension, diabetes mellitus, peripheral vascular disease, migraine headache, Raynaud syndrome, anemia, systemic hypotension, and calcium channel blocker use. This study strengthens the evidence for the vascular hypothesis of low-tension glaucoma.

Intraocular asymmetry of visual field defects in primary angle-closure glaucoma, high-tension glaucoma, and normal-tension glaucoma in a Chinese population.

Direct comparison data on spatial patterns of visual field (VF) defects among primary angle-closure glaucoma (PACG), high-tension glaucoma (HTG) and normal-tension glaucoma (NTG) are not available. We aimed to compare the intraocular asymmetry of VF loss among patients with PACG, NTG and HTG across different severity levels. A total of 162 eyes of 114 patients with PACG, 111 eyes of 74 patients with HTG and 148 eyes of 102 patients with NTG were included. VF defects were categorized into 3 stages (early, moderate, and advanced), and each hemifield was divided into 5 regions according to the Glaucoma hemifield test (GHT). The mean total deviation (TD) of each GHT region was calculated. In the early stage, the paracentral, peripheral arcuate 1 and peripheral arcuate 2 regions in the superior hemifield in the NTG group had significantly worse mean TDs than their corresponding regions in the inferior hemifield. In the advanced stage, the central region in the superior hemifield in the PACG group had a significantly worse mean TD than that in the inferior hemifield. There was no significant difference in the mean TD for any of the five regions between hemifields across all severity levels in the in the HTG group. The superior hemifield was affected more severely than the inferior hemifield in all three subtypes of primary glaucoma. This asymmetric tendency was more pronounced in NTG than in PACG and HTG.

Normal-tension Glaucoma Management: A Survey of Glaucoma Sub-specialists in Korea.

PURPOSE: To investigate the current management patterns of glaucoma subspecialists with regard to normal-tension glaucoma (NTG) in Korea and to determine the effect of the two largest NTG trials on their clinical practice. METHODS: A questionnaire survey was sent to glaucoma subspecialist members of the Korean Glaucoma Society. The questionnaire concerned regular practice with respect to NTG and the extent to which it has been influenced by the Collaborative Normal-tension Glaucoma Study and the Low-pressure Glaucoma Treatment Study (LoGTS). RESULTS: A total of 134 glaucoma subspecialists completed the survey, with a response rate of 56%. The survey reported that 88% and 78% of glaucoma subspecialists were familiar with the Collaborative Normal-tension Glaucoma Study and the LoGTS, respectively. With respect to mild or moderate NTG, most of the respondents (87%-91%) tended to treat their patients immediately without waiting for structural or functional progression. Among the respondents, 47 indicated that the LoGTS results-according to which, 20% of the respondents tended to use brimonidine more often-affected their management. The first-choice topical drugs for NTG were prostaglandin analogues (76%), brimonidine (9%), beta-blockers (8%), and topical carbonic anhydrase inhibitor (6%). CONCLUSIONS: Regarding mild-to-moderate NTG, Korean glaucoma subspecialists tended to initiate treatment without waiting for further progression. The impact of the LoGTS on NTG management was not dominant in clinical practice in Korea. Prostaglandin analogs are the most frequently selected first-choice drugs for the management of NTG in Korea.

No association between POU4F1, POU4F2, ISL1 polymorphisms and normal-tension glaucoma.

BACKGROUND: Normal-tension glaucoma (NTG) that occurs despite normal intraocular pressure has genetic predisposition. Since retinal ganglion cells (RGCs) are a key node in pathogenesis of glaucoma, neurodegeneration of RGCs is thought to be the main cause increasing the risk of NTG development. Here, we aimed to investigate the association of polymorphisms in RGC development genes with NTG development. MATERIALS AND METHODS: We performed a case-control association study of 435 patients with NTG and 419 normal controls. We genotyped four single nucleotide polymorphisms (SNPs) in genes responsible for RGC development, namely POU4F2 (rs13152799 and rs1504360), POU4F1 (rs9601092), and ISL1 (rs2288468), by either real-time PCR or PCR-RFLP, and evaluated its association with the risk of NTG development. RESULTS: No significant association was observed between the candidate SNPs and NTG development. CONCLUSIONS: To the best of our knowledge, this is the first report exploring the association between genes regulating RGC development and NTG susceptibility. Our data could provide a reference for further researches that focus on finding additional potential SNPs of POU4F2, POU4F1, ISL1 or other RGC development genes for NTG.

Normal tension glaucoma in obstructive sleep apnea syndrome: A structural and functional study.

This study characterized and evaluated normal tension glaucoma (NTG) in obstructive sleep apnea syndrome (OSAS).In this retrospective, cross-sectional study, all participants were examined with polysomnography (PSG). Functional parameters of standard automated perimetry (SAP) were recorded. Structural parameters in optical coherence tomography angiography (OCTA) included peripapillary superficial vessel density (VD RPC), peripapillary whole-layer (VD NH), and superficial and deep macular area VD. Participants were categorized into perimetric and nonperimetric groups by SAP result. Low reliability of SAP and signal strength index <50 in OCTA were excluded.Severity of OSAS was graded by apnea-hypopnea index (AHI) in PSG. Those with moderate/severe OSAS (AHI ≥ 15, n = 39) had longer neck circumference and shorter ocular axial length than mild OSAS (AHI < 15, n = 14). Furthermore, there was significantly higher AHI and larger neck circumference in the NTG perimetric group (n = 27) than in the control group (n = 26; p < 0.001 and p = 0.047, respectively). Superficial and deep-layer peripapillary and macular area VD significantly decreased in the perimetric group. Overall, structural and functional parameters show that VF PSD was negatively correlated with VD NH and VD RPC (p = 0.007, p = 0.015); and VF MD was positively correlated with VD NH (p = 0.029), but not significantly to VD RPC (p = 0.106).OSAS is a risk factor of NTG. With aid of OCTA, whole-layer retinal capillary dropout supports that the vascular dysregulation of OSAS leads to NTG.

Lack of Correlation between ASB10 and Normal-tension Glaucoma in a Population from the Republic of Korea.

Purpose: Ankyrin repeats and suppressor of cytokine signaling box-containing protein 10 (ASB10) was identified as a novel gene for glaucoma. Since then, there have been reports on the association of ASB10 with glaucoma in various ethnic populations. In these studies, patients with different glaucoma types were included. Thus, we investigated the relationship between ASB10 and NTG in a Korean cohort.Methods: Whole-exome sequencing was performed to identify the ASB10 variants in one patient with a strong NTG family history. A total of 263 participants, comprising 157 NTG patients and 106 control subjects, were analyzed for ASB10 gene single nucleotide polymorphisms (SNPs).Results: Nine variants of the ASB10 gene were identified using whole-exome sequencing analysis, including four exonic SNPs. Of the exonic variants, three were known polymorphisms (rs3800791, rs2253592, and rs77615410), and one was newly reported (rs552803353). A nonsynonymous variant, rs552803353 was predicted as functionally damaging using PolyPhen-2. The exonic SNPs were compared against gene sequences of the control group in the NTG cohort. However, the minor allele frequency (MAF) of rs552803353 was found to be 0.029 and 0.038 in NTG cases and control subjects, respectively. The MAF of rs3800791 was found to be 0.096 and 0.118 in NTG cases and control subjects, respectively, and the MAF of rs77615410 was found to be 0.220 and 0.245 in NTG cases and control subjects, respectively, which were higher than those reported by previous studies. Genetic association analysis of four ASB10 SNPs revealed no significant difference in genotype distribution between NTG cases and control subjects in allelic, dominant, or recessive models (all, P > .05).Conclusions: The present study indicated that the MAFs of ASB10 gene polymorphisms showed a large difference among various ethnic groups, and that ASB10 gene polymorphisms may not be associated with genetic susceptibility to NTG in a Korean cohort.

Association of HK2 and NCK2 with normal-tension glaucoma in a population from the Republic of Korea.

BACKGROUND: Previous studies have reported the association of HK2 and NCK2 genes with normal-tension glaucoma (NTG) in Japan, but there has been no follow-up study in other countries, so the relevance of these genes to NTG appears uncertain at present. Thus, we investigated the relationship between the HK2 and NCK2 genes and NTG in a Korean NTG cohort. METHODS: In total, 154 unrelated Korean patients with NTG and 101 normal Korean controls were recruited. Thus, a total of 255 participants were analyzed for NCK2 (rs2033008) and HK2 (rs678350) gene polymorphisms. RESULTS: The minor allele frequency (MAF) of rs678350 was significantly higher in NTG patients (MAF = 0.32) than in controls (MAF = 0.23) (OR, 1.586; 95% CI, 1.058 to 2.375; P = 0.028). This trend was more significant in the dominant model (OR, 1.908; 95% CI, 1.144 to 3.180; P = 0.015). When we performed logistic regression analysis to adjust for age, both the allelic and dominant models were still statistically significant. No significant difference was observed in rs2033008 allele or genotype frequencies between the NTG patients and control subjects. CONCLUSIONS: The current study suggested that HK2 gene polymorphism may contribute to the genetic susceptibility to NTG.

Optic disc cupping characteristics of normal pressure hydrocephalus patients with normal-tension glaucoma.

We examined the potential association of idiopathic normal pressure hydrocephalus (iNPH) with the generation of normal-tension glaucoma (NTG), to explore possible relationships between intracranial pressure (ICP) and the presence of glaucoma, and to compare disc morphology of NTG patients with or without iNPH. We investigated 20 iNPH patients, examined the prevalence of glaucoma, and compared the optic discs of NTG patients with iNPH (n = 11) and age-matched NTG patients without iNPH (n = 16). All data were collected prior to the treatment of iNPH, to eliminate the possibility that the treatment may have contributed to the progression of NTG. The diagnoses of NTG were made using visual field data, intraocular pressure measurements, fundoscopy, and optical coherence tomography (OCT). Using OCT, the optic nerve disc depth was also measured. The ICP was higher in the iNPH with NTG compared to iNPH without NTG (p = 0.0425), and the cupping depths of the discs of NTG patients with iNPH were significantly shallower compared with those of NTG patients without iNPH (p = 0.0097). Based on the difference in cupping depth, NTG patients with iNPH may have a different morphology from typical glaucoma patients, which could in turn reflect a different pathogenesis compared to NTG patients without iNPH.

Association between normal tension glaucoma and the risk of Alzheimer's disease: a nationwide population-based cohort study in Taiwan.

OBJECTIVES: To investigate a possible association between normal tension glaucoma (NTG) and an increased risk of developing Alzheimer's disease (AD). DESIGN: Retrospective cohort study. SETTING: NTG group and the comparison group were retrieved from the whole population of the Taiwan National Health Insurance Research Database from 1 January 2001 to 31 December 2013. PARTICIPANTS: A total of 15 317 subjects with NTG were enrolled in the NTG group, and 61 268 age-matched and gender-matched subjects without glaucoma were enrolled in the comparison group. PRIMARY AND SECONDARY OUTCOME MEASURES: Kaplan-Meier curves were generated to compare the cumulative hazard of AD between the two groups. A multivariable Cox regression analysis was used to estimate the adjusted hazard ratios (HRs) of AD, adjusted for diabetes, hypertension, hyperlipidaemia, coronary artery disease and stroke. Furthermore, risk factors for developing AD among the NTG group were investigated. RESULTS: The mean age of the cohort was 62.1±12.5 years. Patients with NTG had significantly higher proportions of diabetes, hypertension, hyperlipidaemia, coronary artery disease and stroke than the comparisons. Patients with NTG had a significantly higher cumulative hazard for AD than the comparisons (p<0.0001). In the multivariable Cox regression after adjustment for confounders, the NTG group had a significantly higher risk of AD (adjusted HR 1.52; 95% CI 1.41 to 1.63). Moreover, in the NTG group, when we compared the effects of different types of glaucoma eye drops, none of the eye drops used were significant risk factors or protective factors for AD. CONCLUSIONS: People with NTG are at a significantly greater risk of developing AD compared with individuals without glaucoma. Among patients with NTG, none of the glaucoma eye drops used significantly changed the risk of subsequent AD.

Dietary Niacin and Open-Angle Glaucoma: The Korean National Health and Nutrition Examination Survey.

Glaucoma is a leading cause of loss of sight. High intraocular pressure (IOP) is the most critical risk factor. However, glaucoma develops even within a normal IOP range. Normal tension glaucoma (NTG) is more common in Asia, whereas high tension glaucoma is more common in Western countries. The pathogenesis of glaucoma, especially NTG, is poorly understood. We evaluated the correlation between dietary nutrient intake and glaucoma using data from subjects ≥40 years old from the ongoing, nationwide, population-based study, the Korean National Health and Nutrition Examination Survey V (2008-2012). Dietary intake was determined using the 24 h recall method. Fiber (g/day), ash (g/day), calcium (mg/day), phosphorus (mg/day), iron (mg/day), sodium (mg/day), potassium (mg/day), ß-Carotene (µg/day), retinol (µg/day), vitamin A (µg Retinol Equivalents/day), thiamine (mg/day), riboflavin (mg/day), niacin (mg/day), and vitamin C (mg/day) were included in nutrient intake data. All nutrient intake was divided into quartiles. The mean IOP did not differ according to quartiles from any nutrients (all p > 0.05). After adjusting for age, gender, income status, education level, smoking, alcohol consumption, physical activity, diabetes, hypertension, IOP, and total energy, the intake of niacin was associated with glaucoma (p = 0.013). Among subjects with IOP ≤ 21 mmHg, only niacin was related to glaucoma in a multivariate analysis (p = 0.022). Dietary nutrient intake was associated with open-angle glaucoma independent of IOP. Individuals with NTG showed lower intake of niacin among nutrients. This finding suggests the possibility that proper diet counseling may be another modifiable factor, aside from IOP, particularly among patients with NTG.

[Significance of Helicobacter pylori Diagnostic in Glaucoma]. / Bedeutung der Helicobacter-pylori-Diagnostik beim Glaukom.

Glaucoma is one of the most common causes for blindness worldwide. Even if some risk factors for this disease are known, like increased intraocular pressure or increased age, its pathomechanism is still not fully understood. Multiple studies recently analyzed the role of a Helicobacter pylori infection in the glaucoma pathogenesis. Several studies showed a correlation, while others did not come to this conclusion. In summary, it is very likely that a Helicobacter pylori infection coincides with an increased risk for a primary open-angle or normal-tension glaucoma. Still, larger studies, with strict inclusion and exclusion criteria, as well as age-matched control groups, are needed to find out if a Helicobacter pylori infection really leads to a higher risk for glaucoma.

Is atrial fibrillation a risk factor for normal-tension glaucoma?

Glaucoma (GL) and atrial fibrillation (AF) are diseases of significant social importance. Cardiovascular disorders such as systemic hypertension, hypotension, increased blood viscosity, vasospasm, and diabetes are potential risk factors of GL, especially when intraocular pressure is not elevated. Only a few studies have reported a possible connection between cardiac arrhythmias and GL. The purpose of this study was to evaluate the risk of GL in patients with AF.A total of 117 patients were included in the study, 79 with AF (AF group) and 38 with sinus rhythm (Control group), matched for age and sex. The mean ±â€Šstandard deviation age was 73.6 ±â€Š7.2 and 71.6 ±â€Š4.7 years for the AF and control groups, respectively. There were no statistically significant differences in the percentage of systemic hypertension, congestive heart failure, diabetes mellitus type 2, or vascular disease between the groups. Patients were examined for the presence of normal-tension glaucoma (NTG) by an ophthalmologist.NTG was confirmed in 40 patients (34.2%) in the entire group, with 35 (44.3%) in the AF group and 5 (13.15%) in the Control group. The incidence of NTG was significantly higher in the AF group (P = .0221). Women represented 60% of GL patients in the AF group and 80% in the control group. There were no significant differences in intraocular pressure between the groups (mean ±â€Šstandard deviation, 14.3 ±â€Š2.3 vs. 14.2 ±â€Š2.8 mmHg, P = .4202). Approximately three-fourths of patients with AF and NTG had early visual field damage based on the Hodapp classification.AF, independent of other known cardiovascular risk factors, increases the risk of developing NTG. Many AF patients do not have conspicuous symptoms of GL, so understanding the possible risk of its development is critical because early detection might help to prevent later visual impairment and even irreversible blindness.

Intereye comparison of ocular factors in normal tension glaucoma with asymmetric visual field loss in Korean population.

PURPOSE: To identify ocular parameters corresponding to asymmetric visual field (VF) loss in normal tension glaucoma (NTG) through intereye comparisons. PATIENTS AND METHODS: Medical records of NTG patients with asymmetric and symmetric VF losses were retrospectively reviewed. The criterion for asymmetry in VF was 6 dB difference of mean deviation. Refractive error, intraocular pressure (IOP), central corneal thickness, ovality index, and peripapillary atrophy (PPA)/disc area ratio were obtained from each patient. Intereye comparison was performed for asymmetric group, symmetric group, and myopic and nonmyopic asymmetric subgroups. RESULTS: We included 155 patients; 110 patients in asymmetric group and 45 patients in symmetric group. In intereye comparison for total asymmetric group, refractive error (P = 0.006), initial IOP (P = 0.001), ovality index (P = 0.008), and PPA (P < 0.001) were significantly asymmetric. For myopic subgroup, refractive error (P = 0.004), ovality index (P = 0.001), and PPA (P = 0.003) were significant factors. For nonmyopic subgroup, initial IOP (P = 0.003) and PPA (P = 0.007) were significant factors. Symmetric group showed no significant difference between the eyes. Multivariate analysis demonstrated that refractive error (P = 0.002) and PPA (P = 0.028) were significant factors in myopic subgroup, and initial IOP (P = 0.022) and PPA (P = 0.002) were significant factors in nonmyopic subgroup. CONCLUSIONS: In this intereye comparison, the more myopic eye in myopic NTG patient, and the more pressured eye in nonmyopic NTG patient demonstrated more severe VF loss. Myopic and nonmyopic patients may follow different pathophysiologic processes. Discriminative attentions should be paid to NTG patients by subtypes.

Clinical Features of Japanese Patients with Central Retinal Vein Occlusion Complicated by Normal-Tension Glaucoma: A Retrospective Study.

PURPOSE: The association of central retinal vein occlusion (CRVO) with primary open-angle glaucoma (POAG) or ocular hypertension has been reported, and lowering intraocular pressure (IOP) helps to improve the retinal circulation in eyes with CRVO. However, the clinical features of CRVOs with normal-tension glaucoma (NTG) are not well known. Therefore, we investigated Japanese CRVO patients with NTG. METHODS: We retrospectively investigated 234 CRVO patients over 5 years, with follow-ups of more than 12 months, and evaluated the prevalence of glaucoma. RESULTS: Of the 234 CRVO patients, 18 (7.7%) were diagnosed with NTGs (n = 10) or POAGs (n = 8). Seven POAG (87.5%) and 3 NTG (30%) patients had systemic hypertension. At the initial CRVO evaluation, 6 NTGs showed a significantly increased IOP; mean IOP was 13.3 mm Hg before CRVO, 16.2 mm Hg at CRVO, and 13.5 mm Hg at the final visit. CONCLUSIONS: The proportion of NTGs with systemic hypertension was low. IOP of NTG patients was significantly elevated at the initial CRVO evaluation, even in the presence of anti-glaucoma drugs.

Incidence of and risk factors for glaucoma in lost-to-follow-up normal-tension glaucoma suspect patients.

BACKGROUND: To investigate the incidence and risk factors of glaucoma in normal-tension glaucoma (NTG) suspect patients who had been lost-to-follow-up for at least 24 months. METHODS: Seventy-two eyes of 72 NTG suspect patients who returned to the hospital after at least 24 months of follow-up loss were enrolled in this study between January 2009 and June 2013. The data were collected retrospectively. The incidence of glaucoma was investigated using a comprehensive glaucoma evaluation in lost-to-follow-up NTG suspect patients. The patients were classified into the glaucoma group, who developed glaucoma during the study period, and the glaucoma suspect group, who did not, to analyse the risk factors for glaucoma. RESULTS: The number of patients who developed glaucoma was 7 (9.7 %) out of the 72 NTG suspect patients who had been mean lost-to-follow-up for 44 months. The rate of progression from suspected to glaucoma was 2.6 %/year. In the glaucoma group, the baseline intraocular pressure (IOP) was 18.43 ± 2.44 mmHg, and the average retinal nerve fiber layer (RNFL) thickness was 78.14 ± 7.60 µm; in the glaucoma suspect group, the baseline IOP was 14.95 ± 2.47 mmHg, and the average RNFL thickness was 92.55 ± 7.65 µm. The study results showed that the glaucoma group had higher baseline IOP and a thinner average RNFL (p = 0.003; p < 0.001). The results of the multivariable logistic regression analysis showed that the risk factors for glaucoma were high baseline IOP (OR = 1.63; p = 0.037) and a thin average RNFL (OR = 0.841; p = 0.004). CONCLUSIONS: The incidence of glaucoma in the lost-to-follow-up NTG suspect patients was 9.7 % for approximately 44 months, at a rate of 2.6 %/year. The risk factors for glaucoma in these patients were high baseline IOP and a thin average RNFL.

Neurodegeneration beyond the primary visual pathways in a population with a high incidence of normal-pressure glaucoma.

PURPOSE: Glaucoma is the most common age-related neurodegenerative eye disease in western society. It is an insidious disease that, when untreated or detected too late, leads inevitably to blindness. An outstanding issue is whether glaucoma should be considered exclusively an eye disease or also a brain disease. To further examine it, we used Diffusion Tensor Imaging (DTI) to study white matter integrity in a Japanese glaucoma population. This population has a very high incidence of normal-pressure glaucoma, in which optic nerve damage occurs in the absence of the elevated eye pressure that characterises the more common form of glaucoma. METHODS: We performed DTI in 30 participants with normal-pressure glaucoma and 21 age-matched healthy controls. We used voxel-wise tract-based spatial statistics to compare fractional anisotropy and mean diffusivity of the white matter of the brain between patients and control group. Whole-brain and region of interest-based analyses served to find associations between diffusion indices and clinical measures of glaucomatous damage. RESULTS: Fractional Anisotropy was significantly lower in glaucoma patients in a cluster in the right occipital lobe (p < 0.05; family-wise error-corrected) comprising fibres of both the optic radiation and the forceps major. Additional analysis confirmed bilateral involvement of the optic radiations and forceps major and additionally revealed damage to the corpus callosum and parietal lobe (p < 0.09; family-wise error-corrected). The region of interest-based analysis revealed a positive association between Fractional Anisotropy of the optic radiation and optic nerve damage. CONCLUSIONS: In this specific population, glaucoma is associated with lower Fractional Anisotropy in the optic radiations, forceps major and corpus callosum. We interpret these reductions as evidence for white matter degeneration in these loci. In particular, the degeneration of the corpus callosum suggests the presence of neurodegeneration of the brain beyond what can be explained on the basis of propagated retinal and pre-geniculate damage. We discuss how this finding links to the emerging view that a brain component that is independent from the eye damage plays a role in the aetiology of glaucoma.