Evaluation of white matter hyperintensities and retinal fiber layer, ganglion cell layer, inner-plexiform layer, and choroidal layer in migraine patients

Retinal neural tissue and vascular calibres in migraine: the Northern Finland Birth Cohort Eye Study

PURPOSE

To evaluate the possible effects of migraine on retinal nerve fibre layer (RNFL), ganglion cell-inner plexiform layer (GC-IPL), macular thickness and retinal arteriolar and venular diameters (CRAE, CRVE) in a population-based birth cohort.

METHODS

375 migraineurs and 1489 healthy controls were included in this cross-sectional cohort study. RNFL, GC-IPL and macular thickness parameters were measured by spectral domain optical coherence tomography (OCT), and vascular parameters were measured from fundus photographs. Migraine was determined by a questionnaire and specific features were selected as covariates (gender, smoking status, systolic blood pressure, refraction and diabetes).

RESULTS

There were no statistically significant differences between healthy controls and migraineurs in average RNFL (p = 0.123), macular (p = 0.488) or GC-IPL (p = 0.437) thickness. Migraine did not have a significant effect on any of the macular or GC-IPL subfields. For RNFL subfields, only temporal inferior was borderline significantly increased in migraineurs (p = 0.039) in adjusted results. No statistically significant differences were found between study groups on retinal vascular calibres CRAE (p = 0.879), CRVE (p = 0.145) or AVR (p = 0.259). GC-IPL thickness was found to be positively correlated with CRAE and CRVE in both study groups as GC-IPL thickness increased together with the increase in CRAE and CRVE (p-trend < 0.001 in both), and a similar trend was detected with central macular subfield thickness and systolic (p-trend < 0.001) and diastolic (p-trend = 0.010) blood pressure, but only in the control group.

CONCLUSION

There were no remarkable differences between migraineurs and healthy controls in retinal vascular or structural parameters in our study.

Migraine eye: correlation between migraine and the retina

Background

Activation of the trigeminal vascular system in migraine releases vasoactive neurotransmitters, causing abnormal vasoconstriction, which may affect the ocular system, leading to retinal damage. The purpose of our study was to determine whether there are differences in each retinal layer between migraine patients and healthy subjects.

Methods

A case-control study recruited 38 migraine patients and 38 age- and sex-matched controls. Optical coherence tomography was used to measure the thickness of the peripapillary and macular retinal nerve fiber layer (pRNFL and mRNFL), ganglion cell layer (GCL), inner plexiform layer (IPL), and inner nuclear layer (INL).

Results

The mean ages of the migraine patients and controls were 36.29 ± 9.45 and 36.45 ± 9.27 years, respectively. Thirty-four patients (89.48%) in both groups were female. The mean disability score was 19.63 ± 20.44 (indicating severe disability). The superior-outer INL of migraine patients were thicker than controls. Thickness of the GCL at temporal-outer sector and mRNFL at the superior-outer sector of the headache-side eyes was reduced. However, the INL of the headache-side-eye showed negative correlation with the disability score. This is the first study having found thinning of the GCL and mRNFL of the headache-side eyes. The INL was also thickened in migraines but showed negative correlation with the disability score.

Conclusions

Increased INL thickness in migraine patients may result from inflammation. The more severe cases with a high disability score might suffered progressive retinal neuronal loss, resulting in thinner INL than less severe cases.

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.

Outer Retinal Layer Thickness Changes in White Matter Hyperintensity and Parkinson's Disease

Purpose: To investigate the thickness changes of outer retinal layers in subjects with white matter hyperintensities (WMH) and Parkinson's Disease (PD).

Methods: 56 eyes from 31 patients with WMH, 11 eyes from 6 PD patients, and 58 eyes from 32 healthy controls (HC) were enrolled in this study. A macular-centered scan was conducted on each participant using a spectral-domain optical coherence tomography (SD-OCT) device. After speckle noise reduction, a state-of-the-art deep learning method (i.e., a context encoder network) was employed to segment the outer retinal layers from OCT B-scans. Thickness quantification of the outer retinal layers was conducted on the basis of the segmentation results.

Results: WMH patients had significantly thinner Henle fiber layers, outer nuclear layers (HFL+ONL) and photoreceptor outer segments (OS) than HC (p = 0.031, and p = 0.005), while PD patients showed a significant increase of mean thickness in the interdigitation zone and the retinal pigment epithelium/Bruch complex (IZ+RPE) (19.619 ± 4.626) compared to HC (17.434 ± 1.664). There were no significant differences in the thickness of the outer plexiform layer (OPL), the myoid and ellipsoid zone (MEZ), and the IZ+RPE layer between WMH and HC subjects. Similarly, there were also no obvious differences in the thickness of the OPL, HFL+ONL, MEZ and the OS layer between PD and HC subjects.

Conclusion: Thickness changes in HFL+ONL, OS, and IZ+RPE layers may correlate with brain-related diseases such as WMH and PD. Further longitudinal study is needed to confirm HFL+ONL/OS/IZ+RPE layer thickness as potential biomarkers for detecting certain brain-related diseases.

Retinal Neurovascular Structural Changes in Optical Coherence Tomography and the Relationship between These Changes and White Matter Hyperintensities in Patients with Migraine

INTRODUCTION

This study aimed to reveal whether retinal nerve fiber layer (RNFL), ganglion cell layer (GCL) inner plexiform layer, and choroidal layer (CL) thicknesses differed in patients with migraine. Optical coherence tomography (OCT) was used to measure these neurovascular structural changes and determine the relationship between these structures and cranial white matter hyperintensities (WMHs).

METHODS

This retrospective comparative registry study included a total of 155 individuals aged 18-55 (mean, 33.50 ± 8.34), consisting of 110 migraine patients and 45 healthy controls.

RESULTS

RNFLs were thinner in the migraine group than the control group but not to a statistically significant degree. However, in both eyes, peripapillary RNLF thickness in some specific quadrants was found to be significantly thinner in the patient group than the control group. GCLs were significantly thinner in the migraine group than the control group. CLs were significantly thicker in the migraine group than in the control group. There was no significant difference between the OCT parameters of patients with and without WMH. An inverse correlation was found between disease duration and CL thickness. CLs were significantly thicker in patients in attack periods than those in attack-free periods. There was no significant difference between the OCT parameters of the migraine with aura and migraine without aura subgroups.

DISCUSSION/CONCLUSIONS

Retinal neural and vascular structures might be affected in migraine sufferers, including those in subgroups. Rebound vasodilation may cause alterations in CL thickness during a migraine attack. Factors other than hypoperfusion may contribute to the pathophysiology responsible for the formation of WMH.

Assessment of the outer retina and choroid in white matter lesions participants using swept-source optical coherence tomography

PURPOSE

To assess the three-dimensional outer retina thickness and choroid in eyes with white matter lesions (WMLs) using swept-source optical coherence tomography (SS-OCT).

METHODS

Participants without dementia and stroke with cerebral WMLs were enrolled in our study. Optical coherence tomography (OCT) and OCT angiography (OCTA) were used to image and evaluate the outer retinal layer, choroidal structure, and perfusion of the choriocapillaris, microvessels of the choroid, respectively. Measurement of the outer retinal thickness, choroidal thickness and perfusion of the choriocapillaris was done by the SS-OCT tool.

RESULTS

Thirty-one eyes from 16 WMLs and 40 eyes from 20 healthy controls were included in the data analyses. Outer retinal thickness was significantly reduced (P < .001) in WMLs participants when compared to healthy controls. Choroidal thickness was also significantly reduced (P < .001) in WMLs participants when compared to healthy controls. Choriocapillaris perfusion was significantly reduced (P = .002) in WMLs when compared to healthy controls. A significant correlation (Rho = .392, P = .032) was seen between the outer retinal thickness and choriocapillaris perfusion in WMLs participants.

CONCLUSIONS

Assessing retinal thickness and choroidal changes with the SS-OCTA as a proxy for WML could prove to be a potentially valuable tool for early detection of cognitive decline and other neurodegenerative diseases.

Comparison of retinal nerve fiber layer, macular ganglion cell complex and choroidal thickness in patients with migraine with and without aura by using optical coherence tomography

BACKGROUND

We compared the choroidal thickness (CT), peripapillary retinal nerve fibre layer thickness (pRNFLT) and macular ganglion cell complex thickness (mGCCT) by using spectral domain optic coherence tomography (SD-OCT) in patients with migraine with aura (MWA), migraine without aura (MWoA), and healthy controls.

METHODS

Thirty-seven patients with MWA, 40 patients with MWoA, and age and sex-matched 50 healthy controls were included in this cross-sectional study. CTs at fovea, nasal to fovea and temporal to fovea, global pRNFLT, four quadrants of pRNFLTs, mGCCTs in superior and inferior hemisphere were measured by SD-OCT. The duration of migraine, monthly attack number and the migraine disability assessment (MIDAS) questionnaire scores were recorded.

RESULTS

The mean foveal CT, nasal CT, and temporal CT in patients with MWA were significantly thinner than those of patients with MWoA and control (p < 0.001) while CTs of patients with MWoA were similar with those of controls. Patients with MWA and MWoA had thinner global pRNFLT, superior and inferior pRNFLT compared to controls but there were no significant differences between two migraineurs groups. Only nasal quadrant of pRNFLT was significantly thinner in patients with MWA than other groups. The superior and inferior mGCCTs were significantly thinner in patients with MWA and MWoA than controls.

CONCLUSION

Our results suggested that dysregulation of blood flow in ocular tissues caused by impairment of autoregulation in migraine. Patients with MWA might have an additional risk of choroidal and retinal ischemia than patients with MWoA and healthy controls.

Visual Evoked Potential Responses after Photostress in Migraine Patients and Their Correlations with Clinical Features

In the past few years, researchers have detected subtle macular vision abnormalities using different psychophysical experimental tasks in patients with migraine. Recording of visual evoked potential (VEP) after photostress (PS) represents an objective way to verify the integrity of the dynamic properties of macular performance after exposure to intense light. VEPs were recorded before and after PS in 51 patients with migraine (19 with aura (MA) and 22 without aura (MO) between attacks, and 10 recorded during an attack (MI)) and 14 healthy volunteers. All study participants were exposed to 30 s of PS through the use of a 200-watt bulb lamp. The P100 implicit time and N75-P100 amplitude of the baseline VEP were compared with those collected every 20 s up to 200 s after PS. VEP parameters recorded at baseline did not differ between groups. In all groups, the VEP recordings exhibited a significant increase in implicit times and a reduction in amplitude at 20 s after the PS. In migraine, the percentage decrease in amplitudes observed at 20 s after photostress was significantly lower than in healthy volunteers, in both MO and MA patients, but not in MI patients. When data for MO and MA patients were combined, the percentage of amplitude change at 20 s was negatively correlated with the number of days that had elapsed since the last migraine attack, and positive correlated with attack frequency. We showed dynamic changes of recovery of VEP after PS depending on the migraine cycle. This finding, in conjunction with those previously attained with other neuromodulatory interventions using VEPs, leads us to argue that migraine-disease-related dysrhythmic thalamocortical activity precludes amplitude suppression by PS.

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.

Structural and Microvascular Changes in the Macular Are Associated With Severity of White Matter Lesions

Purpose: This study aimed to characterize the microvascular and structural changes in the macular that occur in white matter hyperintensities (WMH) using optical coherence tomographic angiography. We also aimed to explore the association between macular microvascular and structural changes with focal markers of brain tissue on MRI in WMH using the Fazekas scale.

Methods: This study enrolled healthy participants who were stroke- and dementia-free. MRI was used to image the cerebral white matter lesions, and Fazekas scale was used to evaluate the severity of the white matter lesions. Optical coherence tomography angiography (OCT-A) was used to image the radial peripapillary capillaries (RPCs), macular capillary plexuses [superficial capillary plexus (SCP) and deep capillary plexus (DCP)] and thickness around the optic nerve head, peripapillary retinal nerve fiber layer (pRNFL).

Results: Seventy-four participants were enrolled and divided into two groups according to their Fazekas score (Fazekas scores ≤ 1 and ≥2). Participants with Fazekas score ≥2 showed significantly reduced RPC density (P = 0.02) and DCP density (P = 0.012) when compared with participants with Fazekas score ≤ 1. Participants with Fazekas score ≥2 showed reduced pRNFL (P = 0.004) when compared to participants with Fazekas score ≤ 1. Fazekas scores were significantly associated with the pRNFL thickness (Rho = −0.389, P = 0.001), RPC density (Rho = −0.248, P = 0.035), and DCP density (Rho = −0.283, P = 0.015), respectively.

Conclusions: Microvascular impairment and neuro-axonal damage are associated with the disease cascade in WMH. We have shown that RPC and DCP densities are significantly affected, and these impairments are associated with the severity of the disease and cognitive function. OCT-A could be a useful tool in quantifying the retinal capillary densities in WMH.

Retinal sublayer defect is independently associated with the severity of hypertensive white matter hyperintensity

PURPOSE

To investigate the association of specific retinal sublayer thicknesses on optical coherence tomography (OCT) imaging with brain magnetic resonance imaging (MRI) markers using the Fazekas scale in hypertensive white matter hyperintensity (WMH) subjects.

METHODS

Eighty-eight participants (32 healthy controls and 56 hypertensive white matter hyperintensity subjects) underwent retinal imaging using the OCT and MRI. A custom-built algorithm was used to measure the thicknesses of the retinal nerve fiber layer (RNFL) and ganglion cell layer and inner plexiform layer (GCIP). Focal markers for white matter hyperintensities were assessed on MRI and graded using the Fazekas visual rating.

RESULTS

Hypertensive WMH showed significantly reduced (p < .05) RNFL and GCIP layers when compared to healthy controls, respectively. A significant correlation was found between the RNFL (ρ = -.246, p < .001) and GCIP (ρ = -.338, p < .001) of the total participants and the Fazekas score, respectively. Statistical differences were still significant (p < .05) when correlations were adjusted for intereye correlation, age, hypertension, smoking, body mass index, and diabetes. Among the cases of hypertensive WMH, higher Fazekas scores were significantly associated (p < .05) with the thinning of both the RNFL and GCIP layers after adjustment of age and other risk factors.

CONCLUSIONS

Retinal degeneration in the RNFL and GCIP was independently associated with focal lesions in the white matter of the brain and deteriorates with the severity of the lesions. We suggest that imaging and measurement of the retinal sublayers using the OCT may provide evidence on neurodegeneration in WMH.

Regional volume changes of the brain in migraine chronification

The pathophysiology of migraine is complex. Neuroimaging studies reveal functional and structural changes in the brains of migraine patients. We sought to explore regional volume differences in intracranial structures in patients with episodic and chronic migraine. Sixteen episodic migraine patients, 16 chronic migraine patients, and 24 normal controls were recruited and underwent 3.0 T MRI scanning. The volumes of 142 brain regions were calculated by an automatic volumetric algorithm and compared with clinical variables. Results demonstrated that the volumes of specific regions in the frontal and occipital lobes, and the right putamen, were increased and the volume of the fourth ventricle was decreased in the episodic migraine patients compared with controls. The volumes of the left basal forebrain, optic chiasm, and, the fourth ventricle were decreased in the chronic migraine patients, while the occipital cortex and the right putamen were larger. Compared to episodic migraine patiants, chronic migraine patients displayed larger left thalamus and smaller frontal regions. Correlation analysis showed that headache frequency was negatively correlated with the volume of the right frontal pole, right lateral orbital gyrus, and medial frontal lobes and positively correlated with the volume of the left thalamus. The sleep disturbance score was negatively correlated with the volume of the left basal forebrain. This suggests that migraine patients have structural changes in regions associated with pain processing and modulation, affective and cognitive processing, and visual perception. The remodeling of selective intracranial structures may be involved in migraine attacks. This study was approved by the Ethics Committee of Chinese PLA General Hospital (approval No. S2018-027-02) on May 31, 2018.

Retinal vascular density evaluation of migraine patients with and without aura and association with white matter hyperintensities

Underlying pathophysiological mechanism of migraine is not all clear; however, recent reports suggested that neurovascular system is involved. We aimed to evaluate the retinal vessel densities of migraine patients with and without aura and the associations with white matter hyperintensities (WMH), using optical coherence tomography angiography (OCTA). We recruited 28 migraine with aura (MWA) patients, 26 migraine without aura (MWO) and age and sex-matched 34 healthy controls in our study. All participants were evaluated with optical coherence tomography (OCT) and OCTA for optic nerve parameters and retinal vessel densities with RTVue XR AVANTI. On macular OCTA, superficial and deeper retinal foveal vessel density (VD) were significantly lesser in MWA and MWO than controls. On optic nerve OCTA, whole optic disc, peripapillary, superior hemisphere, superior layer and temporal layer VD were significantly lesser in MWA and MWO. In group of MWA with the WMH, deeper foveal VD and superior hemisphere VD, average RNFL, superior hemisphere and superior layer were significantly lesser and also foveal avascular zone was significantly larger than the group of without WMH. Alterations of VD in patients with migraine are showed in our study. In addition, in group of MWA these alterations have associations with WMH. Supporting these findings with further reports can be useful to understand the pathophysiology of this disease.

Comparison of optic coherence tomography results in patients with diagnosed epilepsy: Findings in favor of neurodegeneration

BACKGROUND

Epilepsy is a chronic neurological disease characterized with recurrent seizures. Progressive neuronal degeneration is a common consequence of long-term and/or recurrent seizure activity in epilepsy. Optical coherence tomography (OCT) is a new medical imaging technique that displays biological tissue layers as high-resolution tomographic sections. The aim of our study was to evaluate OCT findings in patients with epilepsy and to compare OCT findings in terms of disease duration, presence of status, seizure frequency, and drug use.

METHODS

Forty-three patients who had epilepsy according to the Commission on Classification and Terminology of the International League Against Epilepsy (ILAE) in 2010 and 40 healthy controls were recruited for the study. Disease duration, seizure frequency, status history, and multiple drug use were noted. Retinal nerve fiber layer (RNLF), ganglion cell layer (GCL), inner-plexiform layer (IPL), and choroid thinning were analyzed by using spectral OCT.

RESULTS

The mean RNFL values are 101.48 ± 11.33 in the patient group and 108.76 ± 8.37 in the control group (p = 0.001). The mean GCL thickness values in the patient and control groups are 1.14 ± 0.12 and 1.22 ± 0.05, (p < 0.001). The mean IPL thickness is 0.93 ± 0.09 in the patient group and 0.97 ± 0.05 in the control group (p = 0.02). Choroid thickness is significantly increased in the patient group (p < 0.001).

CONCLUSIONS

Demonstration of RNFL, IPL, and GCL thinning might indicate neurodegeneration, and choroid thickening indicates neuroinflammation. We found no association between disease duration, seizure frequency, status history, and multiple drug use and OCT parameters. Further studies with larger patient groups should clarify the matter.