Vasospasm, its role in the pathogenesis of diseases with particular reference to the eye

Evaluation of macular and peripapillary structure and microvasculature with optical coherence tomography angiography in migraine in the Indian population

BACKGROUND

Migraine has been proposed as a potential contributing factor to ischemic complications involving the retina and optic nerve. Ophthalmic disorders connected with migraine encompass occlusions of the branch and central retinal arteries and veins, alongside anterior and posterior ischemic optic neuropathy. With the advent of optical coherence tomography angiography (OCTA), it is easy to identify these macular subclinical microvascular and structural changes.

AIM

To evaluate macular and peripapillary structural and microvasculature changes in patients with migraine with aura (MA), migraine without aura (MW), and healthy control (HC) participants using OCTA.

METHODS

In this observational cross-sectional study, we studied a total of 100 eyes: (1) 32 eyes of 16 patients with MA; (2) 36 eyes of 18 patients with MW, recruited based on the International Classification of Headache Disorders; and (3) 32 eyes of 16 age and sex-matched healthy participants. Foveal flux, foveal avascular zone (FAZ), peripapillary flux obtained from OCTA, and foveal and peripapillary ganglion cell layer (GCL) thickness calculated via optical coherence tomography were compared among the groups.

RESULTS

The mean FAZ area measured in patients with MA and MW was significantly larger than that in the control participants (P = 0.002). However, there was no significant difference between the FAZ of the MA and MW groups. Macular perfusion in the superficial capillary plexus in patients with MA was significantly lower compared to MW (P = 0.0018) and HCs (P = 0.002). There was also significant thinning of the GCL in patients with MA and MW (P = 0.001) compared to HCs. However, there was no significant difference in temporal GCL thickness between the MA and MW groups.

CONCLUSION

Significant changes have been found in structural and microvascular parameters in patients with migraines compared with HCs. OCTA can serve as a valuable non-invasive imaging technique for identifying microcirculatory disturbances, aiding in better understanding the pathogenesis of different types of migraine and establishing their link with other ischemic retinal and systemic pathologies.

Novel 2D/3D vascular biomarkers reveal association between fundus changes and coronary heart disease

PURPOSE

To compare structural and vascular differences in the macular region of the retina using optical coherence tomography (OCT)/OCT angiography (OCTA) between coronary angiography (CAG)-confirmed coronary heart disease (CHD) patients and non-CHD individuals.

METHODS

The study included 340 eyes from 180 CHD patients and 136 eyes from 68 controls. Imaging was conducted using the AngioVue OCT device with a macula-centered 6 mm ∗ 6 mm field of view. Retinal thickness and 2D/3D vascular-related biomarkers were derived using existing retinal layer segmentation software, and our previously proposed 2D/3D vascular and 3D foveal avascular zone segmentation methods. Statistical analyses included t-tests, Mann-Whitney U tests, chi-square tests, and Pearson's correlation.

RESULTS

The CHD group exhibited significantly lower retinal nerve fiber layer (RNFL) thickness (r = -0.20, P < 0.001) in the inner inferior (I) region, based on macular region layer segmentation. For the 3D OCT images, as defined by the ETDRS grid, both the inner and outer retina layers in the outer superior (out-S) region were significantly thinner in the CHD group. The CHD group showed significantly lower overall 2D fractal dimension (FD) (1.72 ± 0.03 vs. 1.73 ± 0.02, P < 0.001) and vessel skeleton density (VSD) (26.61 ± 4.52 vs. 28.50 ± 3.40, P < 0.001) compared to the control group. The proposed 3D vascular density (VD) feature showed a significant difference between the groups (19.23 ± 5.67 vs. 20.69 ± 5.15, P = 0.048).

CONCLUSION

Thinning of retinal thickness and reduced vascular density are associated with CHD and may serve as valuable, cost-effective biomarkers for assessing coronary artery disease assessment.

Eye yoga for glaucoma: recovery of vascular dysregulation and visual field function-a randomized controlled trial

Purpose

Because stress can aggravate vascular dysregulation (VD) in primary open-angle glaucoma (POAG), stress reduction by eye yoga (EY) was studied if this predictive, preventive, and personalized medical (3PM) approach could help normalize intraocular pressure (IOP), retinal vessel dynamics, and visual fields (VF).

Patients and methods

POAG patients were randomized to an EY (n = 15) or control group (n = 12). EY was practiced daily for 1 h for 1 month at home using an iPod-audio guide while control patients read relaxing books daily.

Results

After intervention, EY patients, but not controls, showed a 6.4% IOP reduction (p = 0.027) and had significant VF improvements (p < 0.001). After EY, pattern deviation recovered in VF regions where small microvessels showed reduced vasoconstriction (artery: p = 0.012; vein: p = 0.042) and improved mean artery diameter recovered significantly (p = 0.015). When pooling data of both groups, recovered VF regions, but not non-recovered fields, showed significantly larger arterial diameter gains (2.4 [- 0.3-5.3] MU) with no adverse events.

Conclusions and 3PM recommendations

Because EY reduces vasoconstriction and improves VF function in POAG, we propose the "eye ball retraction theory," whereby ocular muscle tension is induced by mental stress which is a contributing mechanism, or even the key mechanism, of POAG. Reducing stress by relaxation is therefore a remedy for it improves blood flow as the fundamental mechanism of vision recovery and restoration. VD reduction is therefore a valuable therapeutic target for glaucoma care and eye yoga home exercises are a safe and effective complementary 3PM method of POAG care.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-024-00389-x.

Atlas Subluxation Complex, National Upper Cervical Chiropractic Association Intervention, and Dizziness Improvement: A Narrative Review of Historical Perspectives, Literature Synthesis, and a Path for Future Care

Dizziness is a non-specific and common condition in which the afflicted individual experiences abnormal sensations such as lightheadedness, imbalance, or a false sense of spinning (vertigo). The experience of "dizziness" can result from a wide spectrum of abnormal physiological states, including exhaustion, hypotension, and hypoglycemia, but could also indicate a serious underlying health issue. Since it has many potential generating causes, accurate identification of the underlying etiology of dizziness can present a challenge to clinicians, often resulting in ineffective treatments. We present a hypothesis that atlas subluxation complex (ASC) may comprise an etiological agent of dizziness that can be successfully addressed with National Upper Cervical Chiropractic Association (NUCCA) chiropractic care. In this review, we discuss the pathophysiology of the ASC, introduce the NUCCA chiropractic procedure, and complete a literature review and synthesis. Conceptual evidence, case reports, and theory provide foundational evidence that the ASC may be a contributory factor of dizziness generation and that NUCCA chiropractic corrective care of the ASC may produce favorable dizziness outcomes. However, high-quality studies are lacking. The foundation evidence provides indication that further research via observational studies and randomized controlled trials (RCTs) is warranted.

Systemic Arterial Stiffness and Choroidal Microvascular Insufficiency on the Structural Progression of Normal Tension Glaucoma

PURPOSE

To identify the role of systemic arterial stiffness and choroidal microvascular insufficiency on structural progression of normal-tension glaucoma (NTG).

DESIGN

Retrospective cohort study.

METHODS

A total of 107 early NTG eyes of 88 patients, who underwent pulse wave velocity (PWV) measurements and optical coherence tomography (OCT) angiography (OCT-A) at baseline, were categorized depending on the presence of peripapillary choroidal microvasculature dropout (MvD) and PWV. Differences in glaucomatous progression were analyzed. Structural progression rates were determined using the trend-based analysis of Cirrus OCT.

RESULTS

Thirty-two eyes displayed choroidal MvD (62.7 [95% CI 58.4-67.0] years old, 53.6% males), and 70 eyes did not show any MvD (59.9 (95% CI 57.1-62.6) years old, 53.3% males) at baseline. Patients were followed for 48.4 (95% CI 40.0-56.8) months. When they were further divided based on PWV (high PWV ≥ 1400 cm/sec), those with choroidal MvD and high PWV showed significantly faster thinning in macular ganglion cell-inner plexiform layer (GCIPL; P = .023). In comparison to those with low PWV and no MvD, eyes with high PWV and MvD in the peripapillary area were likely to show fast structural progression (≤-1.2 µm/year) in the macular GCIPL by odds of 6.019 (95% CI 1.619-38.531, P = .025).

CONCLUSIONS

In NTG eyes, GCIPL thinning was faster when choroidal MvD and high systemic arterial stiffness were present. The simultaneous presence of regional and systemic vascular insufficiency may be associated with rapid glaucoma structural progression in eyes with low baseline intraocular pressure.

The Association between the Pulsatile Choroidal Volume Change and Ocular Rigidity

Purpose

To assess the relationship between the pulsatile choroidal volume change (ΔV) and ocular rigidity (OR), an important biomechanical property of the eye.

Design

This is a prospective cross-sectional study.

Subjects

Two hundred seventeen participants (235 eyes) were included in this study. Of those, 18 eyes (18 participants) had exudative retinal disease, and 217 eyes (199 participants) had open-angle glaucoma (39.2%), suspect discs (12.4%), ocular hypertension (14.3%), or healthy eyes (34.1%).

Methods

Pulsatile choroidal volume change was measured using dynamic OCT, which detects the change in choroidal thickness during the cardiac cycle. Ocular rigidity was measured using an invasive procedure as well as using a validated optical method. Correlations between ΔV and OR were assessed in subjects with healthy eyes, eyes with glaucoma, or eyes with exudative retinal disease.

Main Outcome Measures

Ocular rigidity and pulsatile ocular volume change.

Results

In 18 eyes where OR was obtained invasively and ΔV was obtained noninvasively, a significant correlation was found between ΔV and OR (rs = -0.664, P = 0.003). Similarly, a strong inverse correlation was found between the noninvasive measurements of both ΔV and OR (rs = -0.748, P < 0.001) in a large cohort and maintained its significance across diagnostic groups (a more compliant eye is associated with greater ΔV). No correlation was found between ΔV and age, blood pressure, intraocular pressure, axial length, or diagnosis (P ≥ 0.05). Mean ΔV was 7.3 ± 3.4 μL for all groups combined with a range of 3.0 to 20.8 μL.

Conclusions

These results suggest an association between the biomechanics of the corneoscleral shell and pulsatile ocular blood flow, which may indicate that a more rigid eye exerts more resistance to pulsatile choroidal expansion. This highlights the dynamic nature of both blood flow and biomechanics in the eye, as well as how they may interact, leading to a greater understanding of the pathophysiology of ocular disease.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Neurovascular changes of the retina and optic nerve head in episodic migraine

To investigate neurovascular changes; including macular vascular density (VD), thickness of the ganglion cell layer (GCL) and optic nerve head (ONH) parameters in episodic migraine patients. 80 eyes of 40 episodic migraine patients were recruited. Thirty patients having a dominant side of migraine headache were statistically analyzed (5 male and 25 female; mean age 31.67 ± 9.54 years) and compared to 25 eyes of 25 healthy volunteers (5 male and 20 female; mean age of 34.4 ± 12.11 years, p = 0.361). The posterior segment was imaged with Topcon DRI optical coherence tomography (OCT) (Triton Swept source OCT Topcon, Japan), and OCT angiography (OCTA). Comparing the dominant side of migraine patients to controls we found a significant decrease of the VD in the central zone of the superficial and deep capillary plexus (SCP, p = 0.01; DCP, p = 0.004) and an enlarged foveal avascular zone (FAZ, p = 0.054). The GCL thickness was significantly reduced in the central ring (GCL + p = 0.042, GCL +  + p = 0.029), as well as the retinal nerve fiber layer (RNFL) thickness in the temporal quadrant (p = 0.021) and border tissue of Elschnig diameter (BTE, p = 0.035). The duration of migraine showed an inverse correlation with SCP in the nasal quadrant (p = 0.016, r = - 0.445) and with all DCP regions [DCP superior (p = 0.004, r = - 0.519), DCP inferior (p = 0.004, r = - 0.519), DCP nasal (p = 0.006, r = - 0.496), DCP temporal (p = 0.005, r = - 0.508), DCP CSF (p < 0.001, r = - 0.634)]. The dominant side compared to the non-dominant side showed a significant deterioration of the VD in the inferior (p = 0.04) and temporal quadrants (p = 0.023); furthermore, a significant decrease in the GCL +  + inner ring thickness (p = 0.046). Microvascular damage and consequent structural alterations of the retina and optic nerve head occur in the eyes of episodic migraine patient in association with the lateralization of the headache.

A Case Series of Retinal Artery Occlusion: When Time Is of the Essence

This case series discusses the presentation, etiologies, and management of retinal artery occlusions in three patients. The first case was diagnosed as right eye central retinal artery occlusion (CRAO) secondary to a hypercoagulable state as the patient had been newly diagnosed with chronic myeloid leukemia. The second case had right branch retinal artery occlusion (RAO) secondary to a thromboembolic event following a percutaneous transluminal coronary angioplasty procedure. The third case involved a right eye CRAO secondary to vasospastic syndrome. The first case had good visual recovery as the patient presented to us within four hours of the onset. In contrast, the second and third cases presented after seven to eight hours, resulting in poor visual recovery. Though several measures have been devised to reverse the occlusion, the final visual prognosis still depends on the degree of occlusion and the time of presentation, as late presentation is usually associated with irreversible visual loss. Detection of RAO may require a multidisciplinary team approach, and proper and timely management may reverse the ischemic state of the retina.

Using optical coherence tomography and optical coherence tomography angiography to delineate neurovascular homeostasis in migraine: a review

Migraine is one of the world's most debilitating disorders, and it has recently been shown that changes in the retina can be a potential biomarker for the disease. These changes can be detected by optical coherence tomography (OCT), which measures retinal thickness, and optical coherence tomography angiography (OCTA), which measures vessel density. We searched the databases Google Scholar, ProQuest, Scopus, and Web of Science for studies in English using OCT and OCTA in migraineurs, using the search terms "optical coherence tomography," "OCT," "optical coherence tomography angiography," "OCTA" and "migraine." We found 73 primary studies, 11 reviews, and 8 meta-analyses pertaining to OCT and OCTA findings in migraineurs. They showed that migraineurs had reduced retinal thickness (via OCT), retinal vessel density, and greater foveal avascular zone area (via OCTA) than controls. OCTA changes reflect a perfusion compromise occurring in migraineurs as opposed to in healthy controls. OCT and OCTA deficits were worse in migraine-with-aura and chronic migraine than in migraine-without-aura and episodic migraine. Certain areas of the eye, such as the fovea, may be more vulnerable to these perfusion changes than other parts. Direct comparison between study findings is difficult because of the heterogeneity between the studies in terms of both methodology and analysis. Moreover, as almost all case-control studies were cross-sectional, more longitudinal cohort studies are needed to determine cause and effect between migraine pathophysiology and OCT/OCTA findings. Current evidence suggests both OCT and OCTA may serve as retinal markers for migraineurs, and further research in this field will hopefully enable us to better understand the vascular changes associated with migraine, perhaps also providing a new diagnostic and therapeutic biomarker.

Predictors of Glaucomatous Progression in Individuals with Small and Large Optic Discs

PURPOSE

To identify factors associated with glaucomatous progression in individuals with small and large optic discs.

DESIGN

Retrospective review.

SUBJECTS

4505 individuals with glaucoma at UCLA; 233 (59.7%) with small discs, 157 (40.3%) with large discs.

METHODS

Small and large disc sizes were defined by OCT or Heidelberg Retinal Tomography as disc area ≤ 5% (≤ 1.3 mm2) and ≥ 95% (≥ 2.9 mm2), respectively. Medical records were reviewed for demographics, systemic comorbidities, glaucoma type, ocular comorbidities, and ocular surgery. Logistic regression was used to identify predictors of visual field (VF) progression in individuals with small and large discs and predictors of large versus small discs.

MAIN OUTCOME MEASURES

The VF deterioration with mean deviation, pointwise linear regression, and glaucoma rate index (GRI); large vs. small disc.

RESULTS

In individuals with small discs, Asian versus non-Hispanic White ethnicity was associated with increased progression (adjusted odds ratio [aOR] = 4.05; 95% confidence interval [CI] = 1.12-14.59 for GRI). Higher intraocular pressure (IOP) range and peak were associated with increased progression in individuals with both small discs (aOR = 1.12; 95% CI = 1.00-1.27 and aOR = 1.05; 95% CI = 1.00-1.10 per 1 mmHg for range and peak with GRI) and large discs (aOR = 1.35; 95% CI = 1.12-1.66 and aOR = 1.11; 95% CI = 1.03-1.20 per 1 mmHg for range and peak with GRI). Multivariable predictors of having large vs. small discs included vasospastic phenotype (aOR = 2.58; 95% CI = 1.35-5.19) and Black (aOR = 20.46; 95% CI = 8.33-61.84), Hispanic/Latino (aOR = 9.65; 95% CI = 4.14-25.39), Asian (aOR = 4.87; 95% CI = 2.96-8.1), and other (aOR = 2.79; 95% CI = 1.69-4.63) versus non-Hispanic White ethnicity.

CONCLUSIONS

Increased odds of glaucomatous progression were associated with Asian vs. non-Hispanic White ethnicity in glaucoma patients with small optic discs, as well as with increased IOP range and peak in those with small and large discs. Individuals with a vasospastic phenotype and those from racial and ethnic minority backgrounds had increased odds of having large vs. small optic discs. Further characterization of discernible phenotypes would improve disease prognostication and help individualize glaucoma treatment.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Vascular Diseases in Women: Do Women Suffer from Them Differently?

According to the World Health Organization, cardiovascular disease (CVD) is the leading cause of death among women worldwide, yet its magnitude is often underestimated. Biological and gender differences affect health, diagnosis, and healthcare in numerous ways. The lack of sex and gender awareness in health research and healthcare is an ongoing issue that affects not only research but also treatment and outcomes. The importance of recognizing the impacts of both sex and gender on health and of knowing the differences between the two in healthcare is beginning to gain ground. There is more appreciation of the roles that biological differences (sex) and sociocultural power structures (gender) have, and both sex and gender affect health behavior, the development of diseases, their diagnosis, management, and the long-term effects of an illness. An important issue is the knowledge and awareness of women about vascular diseases. The risk of cardiovascular events is drastically underestimated by women themselves, as well as by those around them. The purpose of this review is to draw attention to improving the medical care and treatment of women with vascular diseases.

Originalbeiträge (Originals). Altered microvascular density in patients with anorexia nervosa – an optical coherence tomography angiography (OCTA) pilot study

OBJECTIVES

To investigate macular and peripapillary vascular density (VD) in patients with anorexia nervosa (AN) compared to healthy controls. Methods:Whole face scans of the superficial and deep macular layers and whole face and peripapillary scans of the radial peripapillary capillaries (RPC) were obtained using optical coherence tomography angiography (OCTA, AngioVueR, Optovue) in ten patients with AN and ten age-matched controls.The primary objective was to determine whether there was a difference between the vessel density (VD) in the above areas in AN and controls. P-values ≤ 0.0125 were considered statistically significant. Results: VD in the superficialmacular en-face OCTA image was significantly lower in the study group compared to the control group. Neither the deepmacula nor the radial peripapillary capillary (RPC) in the whole-face image nor the RPC-peripapillary imaging appeared to be significantly different. Conclusion: Patients with AN showed reduced VD in the superficialmacular layers compared to healthy controls, which can be discussed as a consequence of the malnutrition. OCTA could be a useful non- invasive tool to detect reduced peripheral blood supply to show vascular changes that occur before ocular symptoms.

Giant-cell arteritis related strokes: scoping review of mechanisms and rethinking treatment strategy?

Stroke is a rare and severe complication of giant cell arteritis (GCA). Although early diagnosis and treatment initiation are essential, the mechanism of stroke is often related to vasculitis complicated by arterial stenosis and occlusion. Its recurrence is often attributed to early steroid resistance or late GCA relapse, so immunosuppressive treatment is often reinforced. However, many questions concerning the mechanisms of stroke remain elusive, and no review to date has examined the whole data set concerning GCA-related stroke. We therefore undertook this scoping review. GCA-related stroke does not necessarily display general signs and inflammatory parameters are sometimes normal, so clinicians should observe caution. Ischemic lesions often show patterns predating watershed areas and are associated with stenosis or thrombosis of the respective arteries, which are often bilateral. Lesions predominate in the siphon in the internal carotid arteries, whereas all the vertebral arteries may be involved with a predominance in the V3-V4 segments. Ultrasonography of the cervical arteries may reveal edema of the intima (halo sign), which is highly sensitive and specific of GCA, and precedes stenosis. The brain arteries are spared although very proximal arteritis may rarely occur, if the patient has microstructural anatomical variants. Temporal artery biopsy reveals the combination of mechanisms leading to slit-like stenosis, which involves granulomatous inflammation and intimal hyperplasia. The lumen is sometimes occluded by thrombi (<15%), suggesting that embolic lesions may also occur, although imaging studies have not provided strong evidence for this. Moreover, persistence of intimal hyperplasia might explain persisting arterial stenosis, which may account for delayed stroke occurring in watershed areas. Other possible mechanisms of stroke are also discussed. Overall, GCA-related stroke mainly involves hemodynamic mechanisms. Besides early diagnosis and treatment initiation, future studies could seek to establish specific preventive or curative treatments using angioplasty or targeting intimal proliferation.

Retinal and peripapillary vascular density in episodic and chronic migraine cases without aura

BACKGROUND

Migraine is a neurovascular disease that can cause ocular and systemic ischemic damage. Despite from aura, a limited number of studies have considered the effect of the chronic migraine in cases without aura. Our aim was to evaluate the differences in the retinal and optic disk microvasculature among episodic and chronic migraine cases without aura using optical coherence tomography angiography (OCTA) imaging.

METHODS

45 cases with migraine, and 25 control subjects were included in this prospective, cross-sectional study. OCTA was performed at 3 × 3 mm and 6 × 6 mm of the macula and at 4.5 × 4.5 mm of the optic disk. Retinal nerve fiber layer (RNFL) thickness, ganglion cell complex thickness, and vessel densities of the optic nerve and macula were compared among the three groups: a control group, an episodic migraine without aura (EMWOA) group, and a chronic migraine without aura (CMWOA) group.

RESULTS

In EMWOA group, circumpapillary vascular density (cpVD) was not decreased significantly in any quadrants (all, p>0.05). Compared to the control group, CMWOA group had significantly lower RNFL thickness in superior-temporal quadrants (p = 0.002 and 0.006, respectively), while cpVD differed only in the temporal quadrant and temporal inferior sector (p = 0.002 and p = 0.009, respectively).

CONCLUSIONS

Temporal peripapillary perfusion is valuable in the follow-up of chronic migraine cases. Longitudinal studies are needed to determine the place of OCTA in the follow-up of migraine.

Knowledge Mapping of Global Status and Trends for Thromboangiitis Obliterans: A Bibliometrics and Visual Analysis

Objective

Thromboangiitis obliterans (TAO) is a segmental nonatherosclerotic inflammatory vascular disease characterized by recurrent progressive inflammatory reactions and thrombosis in the small and medium-sized arteries and veins of the extremities. However, there are few bibliometric studies on TAO. Therefore, this study was employed to generalize the research status, hotspots and development trends of TAO-related research.

Methods

The data from 1999 to 2022 were collected from the Web of Science core collection database, and analyzed through bibliometrics software. VOSviewer was utilized to carry out academic collaboration between different countries/regions, institutions, and authors, visualization map of co-cited authors, journals, reference, and co-occurring keywords. CiteSpace was used to analyze the dual-map of journals, keyword bursts, and timeline of keywords. Bar and pie charts in this study were statistically analyzed and graphed through Microsoft Excel 2021. Scimago Graphica was applied to map the academic collaboration between different countries/regions.

Results

A total of 553 literatures were involved in this study. Japan at the leading global position not only in the number of publications, but also total citations, average citations and H-index. Institution with the major contribution to TAO research is Mashhad University of Medical Sciences, and Nagoya University. Annals of Vascular Surgery, Angiology, Journal of Vascular Surgery are the main publication channel for articles related to TAO. Fazeli, B., Iwai, T., and Kihara, Y. are major contributors in this field. The studies on TAO keywords could be grouped into four clusters: Etiology, Mechanism, Cell therapy and Clinical therapy.

Conclusion

Although the number of TAO publications has fluctuated over the past 20 years, it has generally shown a steady upward trend. Etiology and treatment research on TAO and some keywords such as trail, therapy, outcome, management, stem cells, angioplasty, and activation will become a hot spot in the future.

Paracentral Acute Middle Maculopathy Following Acute Primary Angle Closure and Acute Primary Angle Closure Glaucoma

Purpose

To report the prevalence, clinical characteristics and risk factors for paracentral acute middle maculopathy (PAMM) following acute primary angle closure (APAC) and acute primary angle closure glaucoma (APACG).

Methods

This retrospective study consecutively recruited patients diagnosed with APAC or APACG. Based on the spectral domain optical coherence tomography characteristics, PAMM eyes were divided into three stages. Characteristics of different stages such as the time from symptoms to treatment (TST), retinal thickness and BCVA improvement were analyzed. The risk factors of PAMM were evaluated by binary logistic regression models.

Results

A total of 781 eyes of 781 APAC or APACG patients were included, and PAMM was found in 22 (2.9%) of them. Stage III eyes had a significantly longer TST than stage I eyes (P = 0.008) while exhibiting significantly thinner retinal thicknesses (P < 0.0001). The BCVA improvement was significantly worse in the eyes treated in stage III than in those treated in stage I (P = 0.008). Older age, longer axial length and without type 2 diabetes were associated with a lower risk of incident PAMM (OR = 0.95, P = 0.028; OR = 0.52, P = 0.019; OR = 3.92, P = 0.022).

Conclusion

PAMM can be secondary to APAC or APACG at a rate of 2.9%. Different visual outcomes were observed in patients who received the intervention at different stages of PAMM. Younger patients with a shorter axial length and type 2 diabetes were found to be more susceptible to PAMM.

Ancillary PanoMap OCT shows the progression of glaucomatous papillomacular bundle defect with disc haemorrhage on the fovea-disc axis

BACKGROUND/AIMS

To identify the spatial relationship between disc haemorrhage (DH) on the fovea-disc axis and retinal nerve fibre layer (RNFL) defect in the papillomacular bundle (PMB) using ancillary PanoMap optical coherence tomography (OCT).

METHODS

We investigated the presence and progression of spatially corresponding PMB defects in glaucomatous eyes with temporally located DH on the fovea-disc axis (FoDi-DH). We identified PMB defects using ancillary PanoMap OCT with guided progression analysis, in addition to red-free photographs.

RESULTS

We studied 36 eyes of 35 glaucoma patients with FoDi-DH, pre-existing PMB defects were observed in 18 eyes (50.0%) at the time and location of the initial FoDi-DH occurrence, 14 (38.9%) of which progressed during the follow-up period. New development of PMB defects occurred in 15 (41.7%) of 18 eyes without pre-existing PMB defects. Overall, FoDi-DH was associated with PMB defects in 33 (91.7%) eyes at locations spatially overlapping the PMB defect. Red-free photography and OCT were complementary in detecting PMB defects and progression. Among 47 cases, 20 were concordant, while 10 and 17 were detected only in photography and OCT, respectively. The central visual field defect increased significantly throughout the follow-up period (p=0.006).

CONCLUSION

Most FoDi-DH cases were related to the presence and progression of glaucomatous PMB defects at locations spatially overlapping the defect. OCT helped clarify changes in PMB defects detected by red-free photograph and the detection of photo-negative PMB defects as well. Similar to inferotemporal and superotemporal-direction DH, temporal DH on the PMB may be an indicator of ongoing RNFL damage that deserves close attention.

Neurovascular dysfunction in glaucoma

Retinal ganglion cells, the neurons that die in glaucoma, are endowed with a high metabolism requiring optimal provision of oxygen and nutrients to sustain their activity. The timely regulation of blood flow is, therefore, essential to supply firing neurons in active areas with the oxygen and glucose they need for energy. Many glaucoma patients suffer from vascular deficits including reduced blood flow, impaired autoregulation, neurovascular coupling dysfunction, and blood-retina/brain-barrier breakdown. These processes are tightly regulated by a community of cells known as the neurovascular unit comprising neurons, endothelial cells, pericytes, Müller cells, astrocytes, and microglia. In this review, the neurovascular unit takes center stage as we examine the ability of its members to regulate neurovascular interactions and how their function might be altered during glaucomatous stress. Pericytes receive special attention based on recent data demonstrating their key role in the regulation of neurovascular coupling in physiological and pathological conditions. Of particular interest is the discovery and characterization of tunneling nanotubes, thin actin-based conduits that connect distal pericytes, which play essential roles in the complex spatial and temporal distribution of blood within the retinal capillary network. We discuss cellular and molecular mechanisms of neurovascular interactions and their pathophysiological implications, while highlighting opportunities to develop strategies for vascular protection and regeneration to improve functional outcomes in glaucoma.

Ocular rigidity and neuroretinal damage in patients with vasospasticity: a pilot study

OBJECTIVE

Evidence suggests that ocular blood flow dysregulation in patients with vasospasticity could occur in response to biomechanical stimuli, contributing to optic nerve head susceptibility in glaucoma. We evaluate the role of vasospasticity in the association between ocular rigidity (OR) and neuroretinal damage, hypothesizing that low OR correlates with greater glaucoma damage in patients with vasospasticity.

DESIGN

Cross-sectional study.

PARTICIPANTS

Patients with open-angle glaucoma (OAG), suspect discs, or no glaucoma.

METHODS

OR was measured using a noninvasive, validated method developed by our group. Retinal nerve fibre layer (RNFL) and ganglion cell complex thicknesses were acquired using spectral domain optical coherence tomography. Vasospasticity was assessed by a standardized questionnaire that was based on existing validated questionnaires and adapted to our requirements. Atherosclerosis was evaluated based on Broadway and Drance's (1998) cardiovascular disease score. Correlations between OR and structural parameters were assessed in patients with vasospasticity and those with atherosclerosis.

RESULTS

Of 118 patients with either OAG (n = 67), suspect discs (n = 26), or no glaucoma (n = 25) who were recruited consecutively, 10 were classified as having vasospasticity, and 37 as having atherosclerosis. In the vasospastic group, significant correlations were found between OR and the minimum ganglion cell complex thickness (rs = 0.681, p = 0.030), the average RNFL thickness (rs = 0.745, p = 0.013), and the RNFL in the temporal quadrant (rs = 0.772, p = 0.009), indicating more damage with lower OR. Similar trends were maintained when applying multiple testing correction; however, only the eighth RNFL clock hour corresponding to the inferior-temporal peripapillary region remained significantly correlated with OR in the vasospastic group (p = 0.015). In contrast, no correlation was found in the atherosclerotic group (p > 0.05).

CONCLUSIONS

The findings of the current pilot study indicate a trend for more neuronal structural damage in less-rigid eyes of patients with vasospasticity, meaning that OR may play a greater role in glaucoma in vasospastic patients than in patients with atherosclerosis. Although these results provide interesting insight into the pathophysiology of OAG, further investigation is needed to confirm our observations.

Vascular dysregulation in glaucoma: retinal vasoconstriction and normal neurovascular coupling in altitudinal visual field defects

Purpose

Vision loss in glaucoma is not only associated with elevated intraocular pressure and neurodegeneration, but vascular dysregulation (VD) is a major factor. To optimize therapy, an improved understanding of concepts of predictive, preventive, and personalized medicine (3PM) is needed which is based on a more detailed understanding of VD pathology. Specifically, to learn if the root cause of glaucomatous vision loss is of neuronal (degeneration) or vascular origin, we now studied neurovascular coupling (NVC) and vessel morphology and their relationship to vision loss in glaucoma.

Methods

In patients with primary open angle glaucoma (POAG) (n = 30) and healthy controls (n = 22), NVC was studied using dynamic vessel analyzer to quantify retinal vessel diameter before, during, and after flicker light stimulation to evaluate the dilation response following neuronal activation. Vessel features and dilation were then related to branch level and visual field impairment.

Results

Retinal arterial and venous vessels had significantly smaller diameters in patients with POAG in comparison to controls. However, both arterial and venous dilation reached normal values during neuronal activation despite their smaller diameters. This was largely independent of visual field depth and varied among patients.

Conclusions

Because dilation/constriction is normal, VD in POAG can be explained by chronic vasoconstriction which limits energy supply to retinal (and brain) neurons with subsequent hypo-metabolism ("silent" neurons) or neuronal cell death. We propose that the root cause of POAG is primarily of vascular and not neuronal origin. This understanding can help to better personalize POAG therapy of not only targeting eye pressure but also vasoconstriction to prevent low vision, slowing its progression and supporting recovery and restoration.

Trial registration

ClinicalTrials.gov, # NCT04037384 on July 3, 2019.

Choroidal thickness in eyes of migraine patients measured using spectral domain-optical coherence tomography: A meta-analysis

Recent developments in high-resolution optical coherence tomography allow evaluation of even the slightest changes of choroidal thickness in various disorders, including migraine. In this review, we analyze the choroidal thickness measurements reported in various studies that compare results between migraineurs and healthy individuals. We searched PubMed, Scopus, and EMBASE to identify relevant literature reporting choroidal thickness in the migraineurs' different macular regions compared with healthy controls. A fixed-effects or random-effects model was applied for the meta-analysis based on the heterogeneity level. Moreover, subgroup analyses, meta-regression, publication bias, and quality assessment were also performed. We identified ten studies involving 580 migraineurs (173 with aura, 128 without aura, and 279 without specification for the presence of aura) and 407 healthy controls to be included in this meta-analysis. Results indicated that average choroidal thickness was significantly decreased in the migraine cases (SMD, -1.28; 95% CI, -2.47 to -0.08; P = 0.04) compared to healthy individuals. Furthermore, both with aura (SMD, -1.16; 95% CI, -1.39 to -0.92; P < 0.0001) and without aura migraine patients (SMD, -0.81; 95% CI, -1.28 to -0.34; P < 0.001) had significantly thinner subfoveal choroid compared to healthy controls. Moreover, subfoveal choroidal thickness in the migraineurs with aura was significantly lower than those without aura (SMD, -0.45; 95% CI, -0.84 to -0.05; P = 0.03). The alterations in choroidal thickness, suggestive of migraine's neurovascular pathophysiology, were tentatively confirmed by this study's findings. Further longitudinal studies with more diverse settings are required to derive more definitive conclusions.

Impact of Systemic Comorbidities on Ocular Hypertension and Open-Angle Glaucoma, in a Population from Spain and Portugal

Open-angle glaucoma (OAG), the most prevalent clinical type of glaucoma, is still the main cause of irreversible blindness worldwide. OAG is a neurodegenerative illness for which the most important risk factor is elevated intraocular pressure (IOP). Many questions remain unanswered about OAG, such as whether nutritional or toxic habits, other personal characteristics, and/or systemic diseases influence the course of glaucoma. As such, in this study, we performed a multicenter analytical, observational, case–control study of 412 participants of both sexes, aged 40–80 years, that were classified as having ocular hypertension (OHT) or OAG. Our primary endpoint was to investigate the relationship between specific lifestyle habits; anthropometric and endocrine–metabolic, cardiovascular, and respiratory events; and commonly used psychochemicals, with the presence of OHT or OAG in an ophthalmologic population from Spain and Portugal. Demographic, epidemiological, and ocular/systemic clinical data were recorded from all participants. Data were analyzed using the R Statistics v4.1.2 and RStudio v2021.09.1 programs. The mean age was 62 ± 15 years, with 67–80 years old comprising the largest subgroup sample of participants in both study groups. The central corneal thickness (ultrasound pachymetry)-adjusted IOP (Goldman tonometry) in each eye was 20.46 ± 2.35 and 20.1 ± 2.73 mmHg for the OHT individuals, and 15.8 ± 3.83 and 16.94 ± 3.86 mmHg for the OAG patients, with significant differences between groups (both p = 0.001). The highest prevalence of the surveyed characteristics in both groups was for overweight/obesity and daily coffee consumption, followed by psychochemical drug intake, migraine, and peripheral vasospasm. Our data show that overweight/obesity, migraine, asthma, and smoking are major risk factors for conversion from OHT to OAG in this Spanish and Portuguese population.

Ocular and Systemic Factors Associated with Glaucoma

Glaucoma is one of the leading causes of irreversible blindness in the world. Although numerous factors have been implicated in the pathogenesis of glaucoma, the main focus of management still remains lowering the intraocular pressure (IOP) by medical or surgical therapy. However, a major challenge is that many glaucoma patients continue to progress despite good control of IOP. In this regard, the importance of other coexisting factors that may contribute to disease progression needs to be explored. Ophthalmologists need to be aware of ocular risk factors and the impact of systemic diseases and their medications, along with lifestyle modifications on the course of glaucomatous optic neuropathy and adopt a holistic approach in treating the eye as well as the patient to alleviate the suffering from glaucoma in a comprehensive manner.

How to cite this article

Dada T, Verma S, Gagrani M, et al. Ocular and Systemic Factors associated with Glaucoma. J Curr Glaucoma Pract 2022;16(3):179-191.

Impact of cerebral hypoperfusion-reperfusion on optic nerve integrity and visual function in the DBA/2J mouse model of glaucoma

Objective

One of the most important risk factors for developing a glaucomatous optic neuropathy is elevated intraocular pressure. Moreover, mechanisms such as altered perfusion have been postulated to injure the optical path. In a mouse model, we compare first negative effects of cerebral perfusion/reperfusion on the optic nerve structure versus alterations by elevated intraocular pressure. Second, we compare the alterations by isolated hypoperfusion-reperfusion and isolated intraocular pressure to the combination of both.

Methods and analysis

Mice were divided in four groups: (1) controls; (2) perfusion altered mice that underwent transient bi-common carotid artery occlusion (BCCAO) for 40 min; (3) glaucoma group (DBA/2J mice); (4) combined glaucoma and altered perfusion (DBA/2J mice with transient BCCAO). Optic nerve sections were stereologically examined 10–12 weeks after intervention.

Results

All experimental groups showed a decreased total axon number per optic nerve compared with controls. In DBA/2J and combined DBA/2J & BCCAO mice the significant decrease was roughly 50%, while BCCAO leaded to a 23% reduction of axon number, however reaching significance only in the direct t-test. The difference in axon number between BCCAO and both DBA/2J mice was almost 30%, lacking statistical significance due to a remarkably high variation in both DBA/2J groups.

Conclusion

Elevated intraocular pressure in the DBA/2J mouse model of glaucoma leads to a much more pronounced optic nerve atrophy compared with transient forebrain hypoperfusion and reperfusion by BCCAO. A supposed worsening effect of an altered perfusion added to the pressure-related damage could not be detected.

Analysis of Variation in Incidence of Optic Disc Hemorrhage According to Seasonal and Temperature Changes

PURPOSE

To investigate seasonal variation in optic disc hemorrhage (DH) by review of fundus photographs representative of 2 calendar years (2019 and 2020).

DESIGN

Retrospective, observational trend study.

METHODS

Patients who visited the Glaucoma Clinic of Seoul National University Hospital and underwent fundus photography were included. All available stereo disc photographs and red-free retinal nerve fiber layer photographs taken between January 1, 2019 and December 31, 2020 were retrospectively reviewed. The monthly incidence rate of DH was determined by reference to the photographs. Seasonal temperature information and patients' intraocular pressure (IOP) information were obtained, organized, and analyzed.

RESULTS

Fundus images of 13,514 eyes were reviewed, and 454 eyes were confirmed to have DH. Poisson regression analyses revealed that as the temperature (T) increased by 1 °C, the DH risk ratio was reduced to 0.979 (95% confidence interval [CI] 0.969-0.989, P < .01). The DH incidence ratio was 1.53 (95% CI 1.23-1.91, P < .01) for the T <10 °C group relative to the T ≥20 °C group. The IOP of the patients with DH in winter was significantly higher than that measured in summer.

CONCLUSION

DH is affected by temperature, and as such, shows seasonal variability. This variability is believed to be caused by temperature-related factors such as IOP or hematological factors. © 2022 Elsevier Inc. All rights reserved.

Multiple attacks of transient monocular visual loss in a previously healthy man: a possible complication after COVID-19 vaccination?

Background

The present case aims to describe a previously healthy man who presented multiple attacks of transient monocular visual loss after Pfizer-BioNTech COVID-19 vaccination and to discuss the possible mechanisms related to occurrence of this condition.

Case presentation

We report a case of multiple attacks of transient monocular visual loss in a previously healthy middle-aged man two weeks after Pfizer-BioNTech COVID-19 vaccination. TVL attacks were described as sudden and painless complete visual loss, lasting about one minute, followed by a full recovery. He presented several non-simultaneous attacks in both eyes, 16 in the right eye, and 2 in the left eye on the same day, fifteen days after receiving the second dose of the Pfizer-BioNTech COVID-19 vaccine. The brain’s magnetic resonance angiography, echocardiogram, and doppler ultrasound imaging of the carotid and vertebral arteries were non-revealing. The complete blood exam revealed a slightly elevated C-reactive protein test. We assessed fundus examination during the transient visual loss attack and revealed diffuse vascular narrowing for both arterial and venous branches, notably in the emergence of the optic disc in right eye. In addition, the circumpapillary optical coherence tomography angiography (OCTA) vessel density map was reduced. Oral verapamil hydrochloride 60 mg twice daily was initiated, and the attacks of transient visual loss improved after two days.

Conclusions

To date, and the best of our knowledge, this is the first case report of multiple transient monocular visual loss attacks due to retinal vasospasm in a previously healthy middle-aged man documented by fundus retinography and OCTA. We discuss in this article the possible association of retinal vasospasm and Pfizer-BioNTech COVID-19 vaccination, probably related to vaccine-induced inflammation.

Retinal Nerve Fiber Layer Analysis in Children With Migraine With and Without Aura Using Optical Coherence Tomography: A Case-Control Study

PURPOSE

To evaluate retinal nerve fiber layer (RNFL) thickness in children with migraine, with and without aura, compared to healthy controls using optical coherence tomography (OCT).

METHODS

In this cross-sectional case-control study, patients with a diagnosis of migraine with aura (MwA) or without aura (MwoA) were considered and healthy children were included as controls. Age, sex, duration of migraine, number of episodes per month, duration of episodes, and use of prophylactic treatment with magnesium were recorded. All patients underwent complete ophthalmologic, neurologic, and pediatric examination. Optic nerve OCT images were obtained using Heidelberg Spectralis OCT (Heidelberg Engineering) and mean global RNFL thickness and the average thickness for each sector were noted.

RESULTS

Thirty-seven children were included: 17 with migraine (9 MwoA and 8 MwA) and 20 controls, the mean age being 13.8 ± 2.9 (range: 8 to 16) and 13.4 ± 2.5 (range: 7 to 16) years, respectively. No significant differences in RNFL thickness were found when comparing all patients who had migraine with healthy controls. However, children with MwA showed statistically significant reductions in RNFL thickness in the temporal (mean difference: 7.83; 95% CI: 0.52 to 15.14, P = .027) and inferior-temporal (mean difference: 16.06; 95% CI: 1.95 to 30.16, P = .027) sectors compared to patients with MwoA. None of the other sectors showed statistically significant differences between groups (all P > .05). In the migraine group, negative correlations were detected between the number of episodes per month and RNFL thickness in the nasal-superior quadrant (r = -.420; P = .021).

CONCLUSIONS

Children with MwA may present a decrease in RNFL thickness, which is associated with the number of episodes per month. [J Pediatr Ophthalmol Strabismus. 20XX;X(X):XX-XX.].

Choroidal Thickness in Multiple Sclerosis: An Optical Coherence Tomography Study

Background and Purpose

To identify changes in the choroidal thickness (CT) in multiple sclerosis (MS) patients with and without optic neuritis (ON) using enhanced-depth-imaging optical coherence tomography (EDI-OCT).

Methods

This cross-sectional study included 96 eyes with MS and 28 eyes of healthy controls. All participants underwent an ophthalmologic examination and EDI-OCT scanning (Spectralis, Heidelberg Engineering, Germany) to assess the CT and the retinal nerve fiber layer (RNFL) thickness. MS patients were divided into two groups: 1) with and 2) without a history of ON. The CT was evaluated in the fovea and at six horizontal and six vertical points at 500, 1,000, and 1,500 µm from the fovea. Paired t-tests were used to compare the groups, and p-value<0.05 was considered as significant.

Results

At all 13 measurements points, the CT was thicker in MS patients than in the healthy controls and was thinner in eyes with ON than in the contralateral eyes, but these differences were not statistically significant. However, the CT was always larger in all points in eyes with a history of ON than in the control eyes. The RNFL was significantly thinner (p<0.05) in both MS and ON eyes than in the control eyes.

Conclusions

The CT did not differ between MS and control eyes, but it was significantly larger in patients with a history of ON, in whom the RNFL was thinner. Further studies are necessary to establish the possible role of the choroid in MS.

Role of ocular blood flow in normal tension glaucoma

Background

Normal tension glaucoma (NTG) is a multifactorial disease in the pathogenesis of which intraocular pressure (IOP)-independent factors play a key role.

Main text

There is considerable evidence that impairment of the ocular blood flow (OBF) is involved both in the onset and progression of this disease. With the development of the hypothesis of OBF in NTG, various imaging techniques have been developed to evaluate the OBF and blood vessels. Moreover, vascular dysregulation, which is a main factor in Flammer syndrome, was frequently observed in NTG patients. Disturbed OBF leads to increased oxidative stress, which plays an important role in the pathogenesis of glaucomatous optic neuropathy. These results suggested that IOP-independent management may provide alternative treatment options for NTG patients.

Conclusions

In this review, we mainly focus on the mechanisms of the abnormal OBF in NTG.

Baseline Vessel Density Parameters for Predicting Visual Field Progression in Open-Angle Glaucoma Eyes With Central Visual Field Damage

PURPOSE

To identify the baseline vessel density (VD) parameters that predict visual field (VF) progression in patients with open-angle glaucoma (OAG) with central visual field (CVF) damage.

DESIGN

Retrospective cohort study.

METHODS

This study enrolled 208 eyes from 208 consecutive patients with OAG with CVF damage at baseline and with a minimum 2 years of follow-up. Optical coherence tomography (OCT) angiography was used to measure circumpapillary and macular VDs in the retina and parapapillary VD in the choroid (pCVD) at the baseline. The circumpapillary retinal nerve fiber layer (cpRNFL) and macular ganglion cell-inner plexiform layer (mGCIPL) thicknesses were also measured as reference standards. Cox proportional hazard analysis was performed to identify the baseline clinical factors associated with VF progression according to the glaucoma stage. The relationships between the CVF mean sensitivity reduction rate during follow-up and the baseline clinical factors were evaluated.

RESULTS

VF progression was detected in 54 eyes (26.0%) during 2.78 years of mean follow-up. A lower pCVD (hazard ratio = 0.916, P = .014) at baseline in early-stage OAG eyes and a reduced baseline average mGCIPL thickness (hazard ratio = 0.896, P = .001) in eyes with moderate to advanced glaucoma were independent predictors of VF progression. The baseline pCVD (β = 0.018, P = .028) in eyes with early-stage glaucoma and the baseline average mGCIPL thickness (β = 0.035, P = .013) in eyes with moderate to advanced glaucoma were significantly correlated with the rate (dB/y) of CVF mean sensitivity reduction.

CONCLUSION

In eyes with OAG with CVF damage, a lower baseline pCVD in early-stage glaucoma and a reduced mGCIPL thickness at baseline in moderate to advanced glaucoma are significantly associated with subsequent VF progression.

Wedge Defects on Optical Coherence Tomography Angiography of the Peripapillary Retina in Glaucoma: Prevalence and Associated Clinical Factors

PRCIS

Among subjects with glaucoma, wedge-shaped defects on optical coherence tomography angiography (OCTA) were associated with disc hemorrhages (DH), paracentral visual field (VF) defects, increased cup-to-disc ratio (CDR), and thinner retinal nerve fiber layer (RNFL).

PURPOSE

To examine determinants of wedge defects on peripapillary OCTA in glaucoma.

MATERIALS AND METHODS

A total of 278 eyes of 186 subjects with mild to severe primary open-angle glaucoma underwent 6×6 spectral-domain OCTA imaging of the superficial peripapillary retina from 2016 to 2020 at an academic practice. Wedge defects were defined as focal microvasculature loss that extends outward from the optic nerve in an arcuate, wedge shape. Logistic regression models controlling for intereye correlation identified variables significantly associated with wedge defects. Eyes with profound microvasculature loss in both hemispheres were excluded. Candidate variables included: age, sex, race or ethnicity, diabetes, hypertension, follow-up duration, baseline untreated intraocular pressure, intraocular pressure at time of imaging, DH history, paracentral VF defects, CDR, central corneal thickness, spherical equivalent, VF mean deviation, RNFL thickness, and glaucoma stage.

RESULTS

Of 278 eyes, 126 (45.3%) had wedge defects in at least 1 hemisphere. In our multivariable logistic regression model, wedge defects were associated with DH history [odds ratio (OR): 3.19, 95% confidence interval (CI): 1.05-9.69, P=0.041], paracentral VF defects [OR: 4.38 (95% CI: 2.11-9.11), P<0.0001], larger CDR [OR: 1.27 (95% CI: 1.03-1.56), P=0.024, per 0.1 increase], and thinner RNFL [OR: 1.71 (95% CI: 1.25-2.34), P=0.0009, per 10 μm decrease].

CONCLUSION

DH history and paracentral VF defects were independently associated with wedge defects on OCTA, which was present in 45.3% of primary open-angle glaucoma patients. These findings may provide insight into glaucoma pathogenesis.

Normal-tension glaucoma: Current concepts and approaches-A review

Normal tension glaucoma (NTG) has remained a challenging disease. We review, from an epidemiological perspective, why we should redefine normality, act earlier at lower pre-treatment intraocular pressure (IOP) level, and the role of ocular perfusion pressures, noting that perfusion is affected by defective vascular bed autoregulation and endothelial dysfunction. The correlation of silent cerebral infarcts (SCI) and NTG may indicate that NTG belongs to a wider spectrum of small vessel diseases (SVD), with its main pathology being also on vascular endothelium. Epidemiological studies also suggested that vascular geometry, such as fractal dimension, may affect perfusion efficiency, occurrence of SCI, SVD and glaucoma. Artificial intelligence with deep learning, may help predicting NTG progression from vascular geometry. Finally, we review latest evidence on the role of minimally-invasive glaucoma surgery, lasers, and newer drugs. We conclude that IOP is not the only modifiable risk factors as, many vascular risk factors are readily modifiable.

Preclinical ocular features in patients with Behçet's disease detected by optical coherence tomography angiography

OBJECTIVE

The aim of this study was to evaluate the perifoveal and peripapillary microvascular structure in patients with Behçet's disease (BD) without clinically ocular involvement.

METHODS

Fifty-six eyes of 28 patients with Behçet's disease without clinically ocular involvement and 50 age-matched healthy eyes were included in this prospective study. Vessel densities (VD) of macula and optic nerve head, foveal avascular zone (FAZ), choroid capillary plexus (CCP) flow area, perifoveal capillary nonperfusion, capillary dilatation and/or telangiectasia and perifoveal capillary arcade disruption were analyzed with optical coherence tomography angiography (OCTA). The relationship between duration of disease and vessel densities was also evaluated.

RESULTS

The FAZ was significantly higher in the BD group (p < 0.001). VD of the foveal and parafoveal region in deep capillary plexus (DCP) were significantly lower in the BD group than in the control group (p < 0.001, p < 0.001). Total disc, peripapillary and inside-disc VD were significantly lower in BD group (p = 0.001, p = 0.002, p = 0.004). Perifoveal morphological changes in DCP were significantly higher in nonocular BD (p < 0.001, p < 0.001, p < 0.001). There was a mild negative correlation between disease duration and whole VD in DCP, total disc VD, peripapillary VD was determined (For whole VD in DCP, r = -0.400, p = 0.035; for total disc VD r = -0.396, p = 0.037; for peripapillary VD r = -0.442, p = 0.018).

DISCUSSION

Perifoveal and peripapillary microvascular changes that can be detected by OCTA may occur in Behçet's patients without clinically ocular involvement.

The eye in migraine: a review of retinal imaging findings in migraine

Migraine is a common headache disorder with neurovascular involvement. Because eyecare practitioners are likely to encounter people with migraine in their everyday practice, it is important to understand how migraine might impact on ocular health. In this narrative review, we provide an update on the latest ophthalmic imaging evidence for retinal involvement in migraine, derived from studies of retinal structure and retinal vascular perfusion using spectral domain and swept source optical coherence tomography (OCT) and OCT angiography. Combined structural OCT evidence from a recent meta-analysis indicates subtle and non-specific thinning of the peripapillary retinal nerve fibre layer (RNFL) in people with migraine, whereas there is little consistent evidence for structural abnormalities of the macular region. Recent advances in OCT angiography technology have also provided an opportunity to visualise microstructural damage and vascular dysregulation in the eyes of people with migraine. However, given that OCT and OCT angiography studies have been exclusively cross-sectional, it is not possible to demonstrate the causal effect of migraine events. Furthermore, the lack of common methodology (different ophthalmic imaging devices and analysis algorithms), and very limited datasets (small samples, heterogenous migraine groups), lead to an inability to make strong conclusions regarding the nature of altered retinal structure and vascular perfusion in migraine. Nevertheless, we discuss the clinical implications of such observations for eyecare practitioners and provide practical advice for the monitoring and management of patients with a history of migraine.

Effect of Nimodipine on Macular and Peripapillary Capillary Vessel Density in Patients with Normal-tension Glaucoma Using Optical Coherence Tomography Angiography

PURPOSE

This study aimed to investigate the effect of nimodipine on peripapillary and macular capillary vessel density (VD) in patients with normal-tension glaucoma (NTG) using optical coherence tomography angiography (OCTA).

METHODS

Sixty mg nimodipine was administered to 20 enrolled NTG patients for 3 months. Patients were treated with glaucoma medication simultaneously. The macular and peripapillary VD were measured automatically by OCTA at baseline, 1.5 h after administering nimodipine, and after 3 months of administering the drug. The retinal nerve fibre layer (RNFL), ganglion cell complex thickness, visual field (VF) testing, intraocular pressure (IOP), blood pressure and pulse rate in each subject were assessed during each follow-up.

RESULTS

Compared with the baseline, the parafovea VD was higher (50.89 ± 4.26 versus 46.80 ± 5.40, P = .044) 1.5 h after administration of nimodipine. After administration of nimodipine for 3 months, the parafovea VD was obviously increased (51.14 ± 5.68 versus 46.80 ± 5.40, P = .039), while IOP, systolic blood pressure, mean arterial pressure and mean ocular perfusion pressure were decreased compared to baseline (all P < .05). No significant differences were found between the radial peripapillary capillary and disc VD. The parafovea VD was positively correlated with the administration of nimodipine (β = 0.39, P = .004), RNFL thickness (β = 0.49, P = .022), and VF mean deviation (β = 0.4, P = .040) in the multivariate analysis.

CONCLUSIONS

Nimodipine effectively increased superficial macular capillary VD, but did not affect peripapillary capillary VD in patients with NTG. This finding indicates that patients with NTG may benefit from the administration of nimodipine.

Assessment of the choroidal thickness, central macular vascular and optic disk perfusion in migraine patients with optical coherence tomography angiography

BACKGROUND

Comparing the central choroidal thickness (CCT) and the perfusion of the macula and optic disk in patients with migraine and control group participants using optical coherence tomography angiography (OCTA).

METHODS

A total of 38 patients diagnosed with migraine and 32 healthy controls were recruited. OCTA scans were performed on all participants. Optic disk, central macular vascular perfusions, and CCT were measured.

RESULTS

Thirty-eight eyes of 38 participants (34 female and 4 male) in the migraine group and 32 eyes of 32 participants (19 female and 13 male) in the healthy control (HC) group were evaluated. The mean age was 42.74 ± 8.14 and 43.09 ± 14.28 years in the migraine group and HC group, respectively. The mean CCT were 314 ± 103 μm and 301 ± 71 μm in the migraine and HC group, respectively (p = 0.54). The mean optic disk perfusions were 44.77 ± 1.93% and 45.25 ± 1.43% in migraine and HC group, respectively (p = 0.25). The mean central macular vascular perfusions were 20.50 ± 8.20% and 18.65 ± 7.46% in migraine and HC group, respectively (p = 0.32). There was a significant negative correlation between CCT and the duration of migraine history (p = 0.004).

CONCLUSIONS

The macular and peripapillary microvasculature were not significantly different in patients with migraine than in HC. As the duration of migraine prolonged, a significant decrease in choroidal thickness was observed.

Optic Disc Vascular Density in Normal-Tension Glaucoma Eyes with or without Branch Retinal Vessel Occlusion

We analyzed the vascular densities (VDs) of the optic disc areas in eyes with normal-tension glaucoma (NTG) according to their branch retinal vessel occlusion (BRVO) status. The VDs of the optic discs and peripapillary areas of 68 NTG patients with BRVO (BRVO group; BRVO eyes and fellow eyes) and 37 patients with NTG alone (control eyes) were measured on angiographic images obtained via swept-source optical coherence tomography angiography. VDs were compared among groups and correlations were assessed. The VD of the optic disc large vessel was the highest in BRVO eyes, followed by the fellow eyes and controls (all P < 0.05). Conversely, small and medium vessel VD was in the opposite order (all P < 0.05). Large vessel VD was negatively correlated with small and medium vessel VD (r = −0.697, P < 0.001). Peripapillary VD was lower in the BRVO eyes than in the control and fellow eyes (P < 0.001 and P = 0.861, respectively). In conclusion, significant changes in the distribution of VDs for optic disc larger vessel and small and medium vessels were observed in both eyes of NTG patients with BRVO, compared to NTG patients without BRVO.

Does hemispheric vascular regulation differ significantly in glaucoma patients with altitudinal visual field asymmetry? A single-center, prospective study

Purpose

Vascular risk factors and ocular perfusion are heatedly discussed in the pathogenesis of glaucoma. The retinal vessel analyzer (RVA, IMEDOS Systems, Germany) allows noninvasive measurement of retinal vessel regulation. Significant differences especially in the veins between healthy subjects and patients suffering from glaucoma were previously reported. In this pilot-study we investigated if localized vascular regulation is altered in glaucoma patients with altitudinal visual field defect asymmetry.

Methods

15 eyes of 12 glaucoma patients with advanced altitudinal visual field defect asymmetry were included. The mean defect was calculated for each hemisphere separately (−20.99 ± 10.49 profound hemispheric visual field defect vs −7.36 ± 3.97 dB less profound hemisphere). After pupil dilation, RVA measurements of retinal arteries and veins were conducted using the standard protocol. The superior and inferior retinal vessel reactivity were measured consecutively in each eye.

Results

Significant differences were recorded in venous vessel constriction after flicker light stimulation and overall amplitude of the reaction (p < 0.04 and p < 0.02 respectively) in-between the hemispheres. Vessel reaction was higher in the hemisphere corresponding to the more advanced visual field defect. Arterial diameters reacted similarly, failing to reach statistical significance.

Conclusion

Localized retinal vessel regulation is significantly altered in glaucoma patients with asymmetric altitudinal visual field defects. Veins supplying the hemisphere concordant to a less profound visual field defect show diminished diameter changes. Vascular dysregulation might be particularly important in early glaucoma stages prior to a significant visual field defect.

Plasma fatty acids and primary open-angle glaucoma in the elderly: the Montrachet population-based study

Background

To compare plasma fatty acids (FAs) between participants with primary open-angle glaucoma (POAG) and participants without neuropathy in an elderly population and to investigate specific FAs pattern in POAG.

Methods

We conducted a population-based study in participants older than 75 years. Participants underwent a comprehensive eye examination with optic nerve photographs, visual field test and optic nerve OCT with RNFL thickness measurement. Glaucomatous status was defined according to the International Society for Epidemiologic and Geographical Ophthalmology classification. Lipids were extracted from plasma and FAs methylesters prepared and analyzed by gas chromatography-mass spectrometry.

Results

Among the 1153 participants of the Montrachet study 810 were retained for analysis and 68 had POAG. The mean age was 82.11 ± 3.67. In multivariable analysis FAs levels were not different between POAG participants and controls (P = 0.078). A FAs pattern characterized by high negative weight of gamma-linoleic acid, eicosapentaenoic acid polyunsaturated FAs (PUFAs), Cis-7 hexadecenoic acid monounsaturated FAs (MUFAs) and high positive weight of eicosadienoic acid, docosatetraenoic acid, docosapentaenoic n-6, alpha linoleic acid PUFAs, eicosenoic acid MUFAs, margaric acid and behenic acid saturated FAs was positively associated with POAG. After adjustment for major confounders, individuals in the upper tertile of FAs pattern scores compared with those in the lower tertile were more likely to present POAG (OR = 3.09 [95% CI 1.29–7.40] P = 0.013).

Conclusions

We found no significant difference regarding isolated plasma FAs between participants with POAG and participants without neuropathy in elderly but specific FAs pattern might be associated with POAG.

BRANCH RETINAL ARTERY WALL RUPTURE AND SUBSEQUENT OCCLUSION DURING PARS PLANA VITRECTOMY WITH MEMBRANE PEEL

PURPOSE

To report a case of branch retinal artery wall rupture and subsequent branch retinal artery occlusion occurring during a routine pars plana vitrectomy with epiretinal membrane and internal limiting membrane peeling.

METHODS

Case report. Multimodal imaging including fluorescein angiography, spectral domain optical coherence tomography (OCT), en face OCT, and OCT angiography were performed.

RESULTS

An 86-year-old woman presented with a symptomatic epiretinal membrane in the right eye. Pars plana vitrectomy with epiretinal membrane and internal limiting membrane peel was performed. During the peel, spontaneous preretinal and intraretinal hemorrhage emanating from an adjacent branch retinal artery developed. At postoperative Week 1, OCT showed retinal thinning and hyperreflectivity suggestive of vascular accident. At postoperative Year 1, OCT imaging revealed retinal atrophy while fluorescein angiography demonstrated the arterial occlusion, and OCT angiography illustrated reduction in retinal perfusion in the region of the branch retinal artery occlusion.

CONCLUSION

The authors report an unusual case of retinal arterial wall rupture and hemorrhaging during routine pars plana vitrectomy with membrane peel resulting in a branch retinal artery occlusion and subsequent retinal atrophy. Surgeons must limit stress on the underlying retina during membrane peel to avoid this surgical complication.

Psychotherapeutic Treatment Options in Glaucoma Patients

Glaucoma poses the second largest cause of severe visual impairment and loss of vision worldwide. Despite the progress in both pharmaceutical and surgical treatments, the attempts to decrease intraocular pressure and prevent progression of glaucomatous optic neuropathy fail in many cases. Hence there is a high demand for additional complementary methods, which can reduce intraocular pressure and improve ocular blood flow as well as mental well-being. On the basis of literature research, the study results published so far on the effectiveness of psychotherapeutical methods in glaucoma therapy will be presented here. The methods of autogenic training, hypnosis and music therapy have already been demonstrated to have a positive effect on intraocular pressure, ocular blood flow and psychological well-being of patients affected by glaucoma. With these methods being not only effective but also cost-efficient, free of side effects and easily administered, they could gain importance in terms of an adjuvant treatment option for patients with glaucoma. However, regular ophthalmological examinations still remain obligatory.

Is Mental Stress the Primary Cause of Glaucoma?

The prognosis of going blind is very stressful for patients diagnosed with "glaucoma". Worries and fear of losing independence is a constant mental burden, with secondary risks of depression and social isolation. But stress is not only a result of glaucoma but also a possible cause (risk factor). This should not be surprising, given that chronic stress can trigger "psychosomatic" organ dysfunctions anywhere in the body. Why should the organ "eye" be an exception? Indeed, glaucoma patients often suspect that severe emotional stress caused their visual field loss or "foggy vision". The hypothesis that stress is a possible cause of glaucoma is supported by different observations: (i) acute and chronic stress increases intraocular pressure and (ii) long-term stress can lead to vascular dysregulation of the microcirculation in the eye and brain ("Flammer's syndrome"), leading to partial hypoxia and hypoglycaemia (hypo-metabolism). Even if nerve cells do not die, they may then become inactive ("silent" neurons). (iii) Degenerative changes have been reported in the brain of glaucoma patients, affecting not only anterograde or transsynaptic areas of the central visual pathway, but degeneration is also found (iv) in brain areas involved in emotional appraisal and the physiological regulation of stress hormones. There are also psychological hints indicating that stress is a cause of glaucoma: (v) Glaucoma patients with Flammer's syndrome show typical personality traits that are associated with low stress resilience: they often have cold hands or feet, are ambitious (professionally successful), perfectionistic, obsessive, brooding and worrying a lot. (vi) If stress hormone levels and inflammation parameters are reduced in glaucoma patients by relaxation with meditation, this correlates with normalisation of intraocular pressure, and yet another clue is that (vii) visual field improvements after non-invasive current stimulation therapy, that are known to improve circulation and neuronal synchronisation, are much most effective in patients with stress resilient personalities. An appreciation of stress as a "cause" of glaucoma suggests that in addition to standard therapy (i) stress reduction through relaxation techniques should be recommended (e.g. meditation), and (ii) self-medication compliance should not be induced by kindling anxiety and worries with negative communication ("You will go blind!"), but communication should be positive ("The prognosis is optimistic").

Evolution of macular microvasculature and retinal layers alterations in patients with macula off retinal detachment after vitrectomy

PURPOSE

To examine the changes in retinal microvasculature in association with retinal layers' condition in patients with rhegmatogenous retinal detachment (RRD) treated with pars plana vitrectomy (PPV).

METHODS

Participants in this study were 89 patients with macula off RRD, who were successfully treated with PPV and gas tamponade without internal limiting membrane peeling, in two centers. All participants underwent best corrected visual acuity (BCVA) measurement, slit-lamp examination, fundoscopy, spectral domain-optical coherence tomography (SD-OCT) and optical coherence tomography angiography (OCTA) at week 5, month 3 and month 6 postoperatively. The fellow untreated eyes were also examined and served as control data.

RESULTS

A statistically significant enlargement in foveal avascular zone (FAZ) in both superficial capillary plexus (SCP) and deep capillary plexus (DCP), accompanied with a statistically significant thinning of inner retinal layers, was noticed 5 weeks postoperatively. These changes, namely FAZ enlargement and thinning of inner retinal layers, in the operated eyes compared to the fellow eyes, remained unchanged till month 6 postoperatively. BCVA improved significantly from week 5 to months 3 and 6 postoperatively. The improvement in BCVA was associated with the gradual ellipsoid zone (EZ) recovery from the first (week 5) till the last examination (month 6).

CONCLUSIONS

The FAZ enlargement in the operated eyes was accompanied with a statistically significant thinning in the inner retinal layers. Inter-correlation of BCVA and EZ integrity was noticed.

Retinal nerve fiber layer changes in migraine: a systematic review and meta-analysis

BACKGROUND

Migraine is one of the most common disabling diseases in the world. Its recurrent attacks may lead to abnormalities in the structure of the brain and retina. An increasing number of studies have investigated retinal nerve fiber layer (RNFL) thickness alterations in migraine by the optical coherence tomography (OCT); however, no consensus has yet reached.

METHOD

We searched Pubmed, Embase, and Web of Science databases to identify studies that investigated RNFL thickness in migraine by OCT measurement and performed a meta-analysis of eligible studies.

RESULTS

Twenty-six studies were included in the meta-analysis, comprising 1530 migraine patients and 1105 healthy controls. The mean RNFL thickness was thinner in the migraine group compared to the control group (SMD =- 0.53). In the subgroup analyses, RNFL thickness were decreased most significantly in the superior (SMD = - 0.71) and inferior (SMD = - 0.63) quadrants among all quadrants. Migraine with aura (SMD = - 0.91) showed a greater effect size of RNFL thickness reduction than migraine without aura (SMD =- 0.47). Spectral-domain OCT (SMD = - 0.55) seems more sensitive to detect RNFL thickness reduction than time-domain OCT (SMD = - 0.44). In addition, age, sex, disease duration, attack frequency, and intraocular pressure were not significantly associated with RNFL thickness.

CONCLUSIONS

The findings from our comprehensive meta-analysis with large datasets strengthen the clinical evidence of the RNFL thickness reduction in migraine. RNFL thickness via spectral-domain OCT measurement demonstrates the potential role in differentiating patients with migraine, especially migraine with aura, from healthy controls.

Retinal nerve fiber layer and ganglion cell layer changes using optical coherence tomography in patients with chronic migraine: a case-control study

Background

Migraine is a prevalent, chronic, and multifactorial neurovascular disease.

Objectives

Our work aimed to investigate if the retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) thickness are affected in patients with chronic migraine to improve the understanding of the etiology and pathophysiology of migraine.

Subjects and methods

A case-control study conducted on 30 patients with chronic migraine and 30 aged and sex-matched healthy controls. Subjects underwent full neurological and ophthalmological history, ophthalmological examination, and measuring RNFL and GCL thickness using the spectral domain-optical coherence tomography (SD-OCT).

Results

RNFL thinning (average, superior, inferior, nasal, and temporal) was significantly more in patients with chronic migraine than healthy control (P = 0.001, 0.022, 0.045, 0.034, and 0.001, respectively). No statistically significant difference was found between chronic migraine patients and healthy controls regarding GCL thickness (average, superior, and inferior) (P value ˃ 0.05).

The average RNFL thickness was significantly thinner in migraine with aura (MwA) than migraine without aura (MwoA) (P = 0.006). The average GCL thickness was thinner in MwA than MwoA (P = 0.039). No statistically significant difference was found between the eyes on the side of the headache and the eyes of the contralateral side regarding RNFL and GCL thickness (P value ˃ 0.05). Age at onset, disease duration, headache frequency, and headache intensity showed an insignificant correlation with OCT parameters.

Conclusion

Retinal changes could be an association with chronic migraine that may be used as a biomarker.

Peripheral vascular disease - a new vascular disease associated with normal tension glaucoma: a case report

INTRODUCTION

Normal-tension glaucoma is known as a multifactorial optic neuropathy. A number of lines of evidence suggested that vascular factors played a significant role in the development of normal-tension glaucoma. The mechanisms underlying the abnormal ocular blood flow in normal-tension glaucoma are still not clear. Peripheral vascular disease seems to be associated with glaucoma populations independent of other cardiovascular risk factors. We found this presentation, for the first time, to our knowledge, as another probable vascular abnormality related to our patient with normal-tension glaucoma, although it is necessary to confirm its pathological effect in future studies.

CASE PRESENTATION

Our patient was a 48-year-old Spanish man without any personal and family history of interest except for circulatory problems of the lower limbs with repetitive ulcers at the frontal and lateral aspects of his legs. His chief complaint was vision loss when he came to consult us. In exploration, his best corrected visual acuity was 20/20 in both eyes; initial intraocular pressure in the right eye was 14-16 mmHg and in the left eye was 16-18 mmHg, with a mild sclerosis of the lens in slit-lamp examination. No inflammation or pigmented lesion was detected in the anterior chamber. Open angle confirmed by Goldman four quadrants gonioscopy. Funduscopic examination revealed a vertical cup disc ratio of 0.6 in the right eye and 0.8 in the left eye. The patient's neuroretinal rim was normal in the right eye, and superior thinning in the left eye was determined. Examination of the patient's visual field showed inferior mild probable nasal scotoma in the right eye and an inferior deep arcuate scotoma defect in the left eye. His optical coherence tomography examination revealed thinning of the peripapillary nerve fiber layer thickness in the left eye and superior loss of macular retinal ganglion cells in the left eye. Normal intraocular pressure values were measured on the intraocular pressure curve without treatment (maximum value, 18-20 mmHg), discarding higher intraocular pressures measured out of office. Ultrasonic pachymetry measured 515/520 μm, and normal intraocular pressure measured with a PASCAL tonometer ruled out probable corneal biomechanical underestimations. The patient's polysomnography study was normal and excluded sleep apnea syndrome. The patient's serial mean blood pressure was normal, especially in the lower limbs (mean value, 125/70 mmHg), ruling out the possibility of systemic hypotension. Thyroidal and coagulation abnormalities, autoimmune disease, and inflammatory disease were excluded. Normal immunologic study and normal vascular biopsy were observed, as well as normal brain magnetic resonance imaging and a normal carotid vascular study. The primary diagnosis was moderate medium peripheral arterial disease in the lower limbs, which was confirmed by echography after ruling out other probable vascular abnormalities related to normal-tension glaucoma.

CONCLUSION

After ruling out other systemic diseases and vascular abnormalities related to normal-tension glaucoma, we found peripheral arterial disease as a probable vascular abnormality related to normal-tension glaucoma in our patient. To our knowledge, this is the first time such a case has been reported. Thus, further research is needed to determine the relevance of these results to the general population.