Ocular pulse amplitude and retina nerve fiber layer thickness in migraine patients without aura

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.

Inventory of Ocular Pulse Amplitude Values in Healthy Subjects and Patients With Ophthalmologic Illnesses: Systematic Review and Meta-analysis

PURPOSE

Many studies have examined the ocular pulse amplitude (OPA) to better understand its physiology and clinical relevance, but the papers are scattered, not consistently indexed, and sometimes difficult to locate. We aimed to identify and summarize the relevant published evidence on OPA and, in a meta-analysis, outline specific differences of this parameter between healthy individual, primary open-angle glaucoma, normal-tension glaucoma, ocular hypertension, and cataract patients.

DESIGN

Systematic review and meta-analysis.

METHODS

A thorough literature search and data extraction were conducted by 2 reviewers independently. Reports on OPA measured by the dynamic contour tonometry in conjunction with different ocular and systemic diseases or potential influencing factors were included.

RESULTS

Of the 527 initially found reports, 97 met the inclusion criteria assessing 31 clinical conditions. A meta-analysis based on 6850 eyes and 106 study arms (68.8%) revealed differences in mean OPA values in millimeters of mercury between various entities. Among healthy eyes, the OPA was 2.58 mm Hg (95% CI: 2.45-2.71), whereas OPA values were higher in glaucoma (unspecified glaucoma 2.73 mm Hg, 95% CI: 2.38-3.08; normal-tension glaucoma 2.66 mm Hg, 95% CI: 2.36-2.97; and primary open-angle glaucoma 2.92 mm Hg, 95% CI: 2.75-3.08). Although ocular hypertension showed the highest OPA values (3.53 mm Hg, 95% CI: 3.05-4.01), the lowest values were found in cataract eyes (2.26 mm Hg, 95% CI: 1.57-2.94).

CONCLUSION

We found different OPA values characteristic of different clinical entities, with above-normal values in glaucoma and ocular hypertension and lower values in cataract patients. Our work is intended for clinicians and researchers who want to get a quick overview of the available evidence or who need statistical data on OPA distributions in individual diseases.

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.

Spontaneous resolution of parafoveal macular hole post YAG hyaloidotomy in a case of Valsalva retinopathy

PURPOSE

To report a rare case of spontaneous resolution of parafoveal macular hole post YAG hyaloidotomy in case of Valsalva retinopathy.

METHODS

Case Report.

RESULTS

A 29-year-old female presenting with sudden diminution of vision in her left eye (LE) for two months following a bout of vomiting was diagnosed with pre-macular haemorrhage. Patient was planned for YAG hyaloidotomy on the same day followed by propped up positioning. On follow up haemorrhage was seen to be cleared around macula with corresponding improvement of visual acuity. Patient was found to have developed a parafoveal hole post procedure which spontaneously healed without any intervention. Visual acuity was subsequently improved with resolution of macular hole as seen on fundus imaging and Optical coherence tomography (OCT).

CONCLUSION

Pre-macular haemorrhage is quite common phenomenon in Valsalva retinopathy cases and YAG hyaloidotomy is an established surgical modality for management of the same in literature with good clinical outcomes. However, formation of macular hole is not very common but described in literature post procedure. It is a rare phenomenon to have spontaneous resolution of macular hole. Hence, observation can be an option for managing such cases.

Predicting post-operative vault and optimal implantable collamer lens size using machine learning based on various ophthalmic device combinations

BACKGROUND

Implantable Collamer Lens (ICL) surgery has been proven to be a safe, effective, and predictable method for correcting myopia and myopic astigmatism. However, predicting the vault and ideal ICL size remains technically challenging. Despite the growing use of artificial intelligence (AI) in ophthalmology, no AI studies have provided available choices of different instruments and combinations for further vault and size predictions. This study aimed to fill this gap and predict post-operative vault and appropriate ICL size utilizing the comparison of numerous AI algorithms, stacking ensemble learning, and data from various ophthalmic devices and combinations.

RESULTS

This retrospective and cross-sectional study included 1941 eyes of 1941 patients from Zhongshan Ophthalmic Center. For both vault prediction and ICL size selection, the combination containing Pentacam, Sirius, and UBM demonstrated the best results in test sets [R² = 0.499 (95% CI 0.470-0.528), mean absolute error = 130.655 (95% CI 128.949-132.111), accuracy = 0.895 (95% CI 0.883-0.907), AUC = 0.928 (95% CI 0.916-0.941)]. Sulcus-to-sulcus (STS), a parameter from UBM, ranked among the top five significant contributors to both post-operative vault and optimal ICL size prediction, consistently outperforming white-to-white (WTW). Moreover, dual-device combinations or single-device parameters could also effectively predict vault and ideal ICL size, and excellent ICL selection prediction was achievable using only UBM parameters.

CONCLUSIONS

Strategies based on multiple machine learning algorithms for different ophthalmic devices and combinations are applicable for vault predicting and ICL sizing, potentially improving the safety of the ICL implantation. Moreover, our findings emphasize the crucial role of UBM in the perioperative period of ICL surgery, as it provides key STS measurements that outperformed WTW measurements in predicting post-operative vault and optimal ICL size, highlighting its potential to enhance ICL implantation safety and accuracy.

Association between time spent on smartphones and digital eye strain: A 1-year prospective observational study among Hong Kong children and adolescents

Prolonged electronic screen use can cause digital eye strain. It can be difficult to rectify due to increasing smartphone reliance, potentially leading to serious public health problems. To investigate the association between time spent on smartphones and digital eye strain (DES) among Hong Kong Chinese school-aged children. Of a total of 1,508 students (748 males, 49.6%) from 8 to 14 years old (mean age = 10.91 years, SD = 2.01) who provided valid data on DES, the 1,298 (86%) who completed the DES questionnaire at 1-year follow-up were included in the analysis. DES was measured using a 10-item scale, and the sum of the 10 dichotomised scores was used as the DES total score. The most commonly reported symptoms were eye fatigue (n = 804, 53.3%), blurred vision (changing from reading to distance viewing) (n = 586, 38.9%), and irritated or burning eyes (n = 516, 34.2%). The DES total scores at baseline and 1-year follow-up were 2.91 (SD = 2.90) and 3.20 (SD = 3.19), respectively. Linear regression controlling for demographic and socio-economic confounders showed that participants with baseline smartphone usage of 241 + min/d had a significantly higher baseline total DES score than those with baseline smartphone usage of 0-60 min/d (2.44 vs 3.21, P < 0.001), and participants with baseline smartphone usage of 181-240 min/d had a significantly higher 1-year follow-up total DES score than those with baseline smartphone usage of 0-60 min/d (2.80 vs 3.50, P = 0.003).

Sensory eye dominance following surgically correction for acute acquired concomitant esotropia of adulthood

BACKGROUND

Acute acquired concomitant esotropia (AACE) is an unusual presentation characterized by acute onset of esotropia after infancy. For patients with AACE of adulthood, the outcome of surgery, which is a common treatment, often shows successful recovery of stereopsis. However, whether surgically corrected patients with AACE of adulthood achieved balanced eyes is yet unclear.

METHODS

Here, we used a binocular phase combination paradigm to quantitatively assess the ocular dominance of 22 surgically aligned patients with AACE of adulthood, which all had regained normal stereopsis after the surgery and 14 adult controls with normal vision. The sensory eye dominance was quantified as the interocular contrast ratio, termed balance point, at which each eye contributed equally to the perception of cyclopean grating.

RESULTS

We found that, normal controls had a mean balance point value close to unity (0.96 ± 0.01), whereas adult AACE patients exhibited apparent interocular imbalance (0.76 ± 0.04), which was significantly different from control group (Mann-Whitney U = 135, P < 0.001, two tailed). In addition, the balance point of adults with AACE didn't correlate with the interval between onset of esotropia and the surgery (r =  - 0.262, p = 0.239), or the length of postoperative follow-up period (r = 0.127, p = 0.575).

CONCLUSION

Our results suggest that, for patients with AACE of adulthood whose eyes had been straightened, there is still residual sensory imbalance which may be a potential risk factor for AACE of adulthood.

The impact of aqueous humor polymerase chain reaction and serological test results for establishing infectious uveitis diagnosis: An Indonesian experience

Objective

To assess the clinical value of aqueous humor real-time polymerase chain reaction (RT-PCR) and serological antibody tests among uveitis patients in Indonesian cohort.

Methods

In this prospective cohort study, single-plex RT-PCR analysis of aqueous samples from 86 new uveitis patients was performed to detect Mycobacterium tuberculosis, Toxoplasmosis gondii, cytomegalovirus, herpes simplex virus, varicella-zoster virus, Epstein-Barr virus, and rubella virus. Specific serological antibodies for suspected pathogens were also obtained. Comparison of PCR and serological antibodies with the initial and final diagnosis were presented.

Results

The diagnostic positivity of aqueous RT-PCR in our cohort was 20% (17/86). The rate of infection as final etiological classification was higher after RT-PCR was performed (45 patients, 52%) compared to initial diagnosis based on clinical presentation alone (38 patients, 44%). In particular, the RT-PCR positivity among patients with infection as the final etiological classification was 33.33% (15/45). A significant difference in the IgG but not IgM toxoplasma value among those with ocular toxoplasmosis as the final diagnosis compared to the other etiologies were observed (3953 (IQR 2707–19562) IU/mL vs 428 (IQR 82–1807) IU/mL; p < 0.0001).

Conclusion

RT-PCR analysis of aqueous fluid from uveitis patients helped confirm a third of infectious uveitis cases in Indonesia. In ocular toxoplasmosis, high IgG but not IgM antibody value might help differentiate those with other etiology.

Evaluation of Ring Amplitude and Factors Affecting Ring Amplitude in Multifocal Electroretinography in Diabetic Eyes

PURPOSE

The aim of this paper was to evaluate the ring amplitudes in diabetic patients and to evaluate the effect of the risk factors for diabetic retinopathy on the ring amplitudes. We also aimed to investigate the success of ring amplitudes in classifying diabetic retinopathy.

METHODS

The study included 32 eyes of 32 diabetic patients without retinopathy (DM), 34 eyes of 34 patients with mild non-proliferative diabetic retinopathy (NPDR) without macular edema, and 62 eyes of 62 age- and sex-matched controls (CG). All subjects were evaluated using mfERG. The relationship between age, diabetes duration, HbA1c and ring amplitudes and the effect of diabetes and hypertension on ring amplitudes were evaluated. Three-way ROC analysis was performed to evaluate the discrimination power of the ring amplitudes.

RESULTS

In the comparison of the ring amplitudes, the amplitudes of the DM and NPDR groups were statistically significantly decreased compared to the CG (p < .05). A moderate to strong correlation was found between the duration of diabetes, HbA1c and ring amplitudes (p < .05). The effect of diabetes decreased towards the peripheral rings and hypertension did not affect ring amplitudes. Volume under the ROC surface of R1 = 0.65 had p < .05 and 95% CI [0.50-0.72], and the best cut-off point pair to differentiate the three classes was found to be c₁ = 217.3, c₂ = 151.2 in three-way ROC analysis.

CONCLUSION

In conclusion, the effects of diabetes are unevenly distributed on the retina topographically. Diabetes affects the central rings more than peripheral rings in multifocal ERG. Both ring densities and ring ratios are effective ways to identify early changes in retinal function.

Simulating the perceptual effects of electrode-retina distance in prosthetic vision

OBJECTIVE

Retinal prostheses aim to restore some vision in retinitis pigmentosa and age-related macular degeneration blind patients. Many spatial and temporal aspects have been found to affect prosthetic vision. Our objective is to study the impact of the space-variant distance between the stimulating electrodes and the surface of the retina on prosthetic vision and how to mitigate this impact.

APPROACH

A prosthetic vision simulation was built to demonstrate the perceptual effects of the electrode-retina distance (ERD) with different random spatial variations, such as size, brightness, shape, dropout, and spatial shifts. Three approaches for reducing the ERD effects are demonstrated: electrode grouping (quads), ERD-based input-image enhancement, and object scanning with and without phosphene persistence. A quantitative assessment for the first two approaches was done based on experiments with 20 subjects and three vision-based computational image similarity metrics.

MAIN RESULTS

The effects of various ERDs on phosphenes' size, brightness, and shape were simulated. Quads, chosen according to the ERDs, effectively elicit phosphenes without exceeding the safe charge density limit, whereas single electrodes with large ERD cannot do so. Input-image enhancement reduced the ERD effects effectively. These two approaches significantly improved ERD-affected prosthetic vision according to the experiment and image similarity metrics. A further reduction of the ERD effects was achieved by scanning an object while moving the head.

SIGNIFICANCE

ERD has multiple effects on perception with retinal prostheses. One of them is vision loss caused by the incapability of electrodes with large ERD to evoke phosphenes. The three approaches presented in this study can be used separately or together to mitigate the impact of ERD. A consideration of our approaches in reducing the perceptual effects of the ERD may help improve the perception with current prosthetic technology and influence the design of future prostheses.

Knowledge of glaucoma and associated factors among primary glaucoma patients in Kunming, China

Background

To investigate the level of knowledge, attitude, and practices about glaucoma and associated factors among primary glaucoma patients in Kunming, China.

Methods

A hospital-based study was conducted on 93 patients from the First Affiliated Hospital of Kunming Medical University. Interviewer-administered questionnaires were used to collect data after written informed consent. Data were analyzed by SPSS 19.0. Univariate and multivariate logistic regression models were used to identify factors. A Chi-square test was used to analyze the association between knowledge of glaucoma and medication compliance, Mann–Whitney U test was performed to assess the relationship between knowledge of glaucoma and quality of life in patients with glaucoma. P-value < 0.05 was considered statistically significant.

Results

Among 93 patients, 55 (59.14%) were aware of glaucoma, 48 (51.61%) had good knowledge of glaucoma, while 45 (48.39%) had poor knowledge. Younger age and duration of glaucoma were associated positively with knowledge of glaucoma. 87 (93.54%) patients got knowledge of their disease from doctors. 79.17% of respondents could use all the anti-glaucoma medications on time, out of which 54.17% had good knowledge of glaucoma while 25.00% had poor knowledge of glaucoma. 30.56% of respondents used to stop anti-glaucoma medications on their own out of which only 9.72% had good knowledge of glaucoma while 20.83% had poor knowledge of glaucoma. Patients with good knowledge of glaucoma had lower scores on the Glaucoma Quality of Life-15 questionnaire. Thus, the compliance to anti-glaucoma medications and glaucoma-related quality of life were better in patients with good knowledge.

Conclusions

The level of knowledge of glaucoma among patients in Kunming is relatively low. Improving knowledge with suitable content for patients through effective multiple means such as the mass media rather than relying only on ophthalmologists may be a veritable first step in combating blindness from glaucoma and enhancing patients' quality of life.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-022-02322-0.

Vision Abnormalities in Children and Young Adults With Cerebral Palsy; A Systematic Review

AIM

The current study was designed to provide detailed information on the prevalence of ocular abnormalities in patients with cerebral palsy (CP).

METHODS

Four international online scientific databases, including Web of Science, PubMed, Scopus, and Google Scholar were systemically searched. First, the titles of the articles were evaluated, and if relevant, their abstracts and full texts were reviewed. The quality of the studies was assessed using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist.

RESULTS

A total of 147 articles were found in the initial search. After applying the exclusion criteria, 65 articles were chosen for further review, from which 17 articles, comprising a total of 1734 patients with CP ranging in age from birth to 22 years, passed the STROBE quality check and were included in this review. The prevalence of ocular abnormalities in the CP patients reported in the evaluated studies ranged between 34% to 100%, with refractive error, strabismus, and nystagmus exhibiting the greatest overall prevalence at 52%, 48%, and 11%, respectively in this population.

CONCLUSION

Early ocular assessment of children with CP is essential for an accurate diagnosis, personalized rehabilitation and performing early interventions to improve their visual function.

Evaluation of retinal microvasculature and foveal avascular zone by the optical coherence tomography angiography in pediatric migraine patients

To compare the foveal avascular zone (FAZ), macular and peripapillary vessel density and retinal nerve fiber layer (RNFL) thickness between pediatric migraine patients and healthy subjects. A total of 108 eyes of 54 children with migraine without aura and 94 eyes of 47 age- and gender-matched healthy subjects were included. Capillary vessel density (CVD) in superficial (SCP) and deep (DCP) retinal capillary plexus, peripapillary region, FAZ, and RNFL thickness were analyzed by optical coherence tomography-angiography. The mean ages were 12.4 ± 3.3 years (range 6-18) in patients with migraine and 12.6 ± 2.9 years (range 5-18) in healthy controls (p = 0.742). The mean FAZ area measured 0.27 ± 0.09 mm² in the pediatric migraineurs and 0.26 ± 0.09 mm² in healthy controls (p = 0.53). There was no significant difference in any measurement of SCP, DCP, peripapillary CVD, and RNFL thickness between study groups (p > 0.05 for all). The pediatric migraine disability assessment test (PedMIDAS) negatively correlated with some of the CVD and RNFL measurements in pediatric migraine patients (p < 0.05). The macular and peripapillary microvasculature were not significantly different during an attack-free period in pediatric migraine patients than in healthy subjects.

Long-term outcome of refractive errors in patients with congenital blepharoptosis who have undergone ptosis surgery

CLINICAL RELEVANCE

Ptosis surgery induces some changes in pre-existing refractive errors and astigmatism. Monitoring refractive outcomes, planning of vision rehabilitation, and amblyopia treatment may be required following ptosis surgery.

BACKGROUND

The few studies published on the outcomes of refractive error after ptosis surgery have been controversial. The aim of this study was to evaluate long-term outcomes of refractive error in patients with congenital blepharoptosis who had undergone ptosis surgery.

METHODS

Patients with congenital blepharoptosis who had undergone ptosis surgery were enrolled in the study. Data on pre- and post-operative refractive errors, marginal reflex distance 1 (MRD1), and levator function were obtained. The data from fellow eyes were used as the control.

RESULTS

The mean patient age of patients undergoing ptosis surgery was 19.8 ± 8 years. The mean follow-up time (time between the operation and post-up measurements) was 4.7 ± 2.1 years with a range of 2-10 years. There were no significant differences in mean refractive changes, being 0.53 ± 0.40D vs. 0.36 ± 0.45D in sphere (p = 0.19) and 0.48 ± 0.56 vs. 0.30 ± 0.23 in cylinder (p = 0.17) in operated and control eyes, respectively. Astigmatism change was, however, significantly higher in the operated eyes with an MRD1 change of ≥2.5 mm (0.84 ± 0.66 vs. 0.27 ± 0.39, p = 0.024). The changes in astigmatism in the operated eyes had a significantly positive correlation with the changes of MRD1 (r = 0.497, p = 0.019). Vectorial analysis showed no significant difference between the changes in astigmatism of the operated and control eyes (0.58 *48º vs. 0.45*53º, respectively).

CONCLUSION

Spherical power of the eyes of patients with congenital ptosis who undergo ptosis surgery does not change. A significant change in astigmatism can be anticipated in eyes with more than 2.5 mm change in MRD1. There is an association between change in astigmatism and MRD1 following ptosis surgery.

Changes in ocular morphology after cataract surgery in open angle glaucoma patients

The purpose of this study was to evaluate intraocular pressure (IOP) pre- and postoperatively, together with anterior chamber angle (ACA) parameters and biometrical results in cataract patients with or without open angle glaucoma (OAG). The prospective observational case-control study included 15 eyes with cataract and OAG in the glaucoma group and 25 eyes with only cataract in control group. Examination included full ophthalmic evaluation, IOP, ocular biometry and anterior segment optical coherence tomography measuring ACA pre- and 6 months postoperatively. OAG patients had a larger absolute IOP reduction compared to control group. Anterior chamber depth (ACD) and ACA width significantly increased in both groups. The OAG group had a tendency of narrower ACA preoperatively, but overall ACA parameters did not differ in either group pre- and postoperatively. The ACD change after surgery correlated with ACA parameters in the control group, but not in OAG group. Axial length was shorter postoperatively in the control group, but remained similar in the OAG group. Absolute IOP reduction was more pronounced in cataract patients with OAG than in cataract patients without glaucoma. ACD and ACA postoperatively increased in both groups and AL shortening was observed in non-OAG in cataract group.

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.

The Spatial Frequency Content of Urban and Indoor Environments as a Potential Risk Factor for Myopia Development

Purpose

To examine the hypothesis that the spatial frequency spectra of urban and indoor environments differ from the natural environment in ways that may promote the development of myopia.

Methods

A total of 814 images were analyzed from three datasets; University of California Berkeley (UCB), University of Texas (UT), and Botswana (UPenn). Images were processed in Matlab (Mathworks Inc) to map the camera color characteristics to human cone sensitivities. From the photopic luminance images generated, two-dimensional spatial frequency (SF) spectra were calculated and converted to one-dimensional spectra by rotational averaging. The spatial filtering profile of a 0.4 Bangerter foil, which has been shown to induce myopia experimentally, was also determined.

Results

The SF slope for natural scenes followed the recognized 1/fα relationship with mean slopes of -1.08, -0.90, and -1.04 for the UCB, UT and UPenn image sets, respectively. Indoor scenes had a significantly steeper slope (-1.48, UCB; -1.52, UT; P < 0.0001). Urban environments showed an intermediate slope (-1.29, UCB; -1.22, UT) that was significantly different from the slopes derived from the natural scenes (P < 0.0001). The change in SF content between natural outdoor scenes and indoors was comparable to that induced by a 0.4 Bangerter foil, which reduced the SF slope of a natural scene from -0.88 to -1.47.

Conclusions

Compared to natural outdoor images, man-made outdoor and indoor environments have spatial frequency characteristics similar to those known to induce form-deprivation myopia in animal models. The spatial properties of the man-made environment may be one of the missing drivers of the human myopia epidemic.

Reliability of foveal avascular zone measurements in eyes with retinal vein occlusion using optical coherence tomography angiography

BACKGROUND

To evaluate the reliability of foveal avascular zone (FAZ) area measurements using optical coherence tomography angiography (OCTA) in eyes with retinal vein occlusion (RVO).

METHODS

Twenty-five OCTA exams of patients with RVO were evaluated retrospectively. Three examiners performed manual measurements of the FAZ, and interrater and intrarater reliability were obtained.

RESULTS

The intraclass correlation coefficient (ICC) for interrater reliability for individual measurements was 0.62 (moderate) with a 95% confidence interval (CI) of 0.40 to 0.79 (p < 0.001). The ICC (95% CI) for intrarater reliability was 0.92 (0.82 to 0.96) for rater A, 0.96 (0.91 to 0.98) for B, and 0.88 (0.76 to 0.94) for C (p < 0.001). In all subanalyses including presence of edema and type of occlusion, interrater reliability was poor/moderate, and intrarater reliability was good/excellent.

CONCLUSION

The FAZ varies significantly among eyes with RVO, so measurements obtained using OCTA should be analyzed with caution due to the moderate level of reliability among different examiners.

Altered Macular Vasculature in Migraine Patients without Aura: Is It Associated with Ocular Vasculature and White Matter Hyperintensities?

Aim

We aimed to determine the alterations in macular and optic nerve vasculature in patients with migraine without aura using optical coherence tomography-angiography (OCTA). We also aimed to determine whether there were clinical differences and alterations in ocular structures in migraine cases with white matter hyperintensities (WMH) using magnetic resonance imaging (MRI). Materials and Methods. The study group comprised patients with migraine without aura and age- and sex-matched healthy controls. Detailed histories of the patients with migraine were recorded including the disease duration, number of attacks in the last month, and attack durations. Visual evoked potentials (VEP) were recorded in all migraine patients. The migraine disability assessment (MIDAS) questionnaire was administered to all patients. The patients were divided into two groups as migraine with WMHs and migraine without WMHs. All subjects underwent a complete neurological and ophthalmological examination. Only the right eyes of the patients were included in the study. Retinal imaging was performed using OCT and OCTA.

Results

A total of 66 migraine patients (29 with WMH and 37 without WMH) and 43 healthy controls were included in this study. Among the migraine patients, disease duration, attack frequency in the last month, attack durations, and the visual analogue scale (VAS), MIDAS, and VEP scores were all similar between those with and without WMHs. There was no significant difference between the groups regarding the ganglion cell complex, foveal, and retinal nerve fiber layer thicknesses. The superficial or deep vascular perfusion densities of the optic disc were also similar between the groups. The foveal avascular zone (FAZ) was significantly larger (P=0.034), and both superficial and deep macular vascular densities were significantly lower in the migraine groups compared with the healthy controls (P=0.001). There was no significant difference concerning the FAZ size or vascular densities between the migraine groups with and without WMHs. In the correlation analysis performed between the migraine patients, the FAZ size was correlated with age and VAS and MIDAS scores while both superficial and deep macular vascular densities were negatively correlated with age and VAS and MIDAS scores.

Conclusion

We suggest that for not only migraine with aura but also migraine without aura, neurovascular structures play an important role in pathogenesis, and novel studies are warranted to elucidate the alterations in these and determine the significance of WMHs in these patient groups.

Factors Associated with Non-compliance for Diabetic Retinopathy Follow-up in an Urban Safety-Net Hospital

PURPOSE

Diabetic retinopathy (DR) is the leading cause of preventable blindness in working-aged adults, and compliance in ophthalmic follow-up appointments is critical to prevent vision loss. However, barriers to follow-up care have not been well studied, especially in socio-economically disadvantaged groups. We investigated the risk factors for non-compliance to DR follow-up appointments in a safety-net county hospital.

METHODS

Two hundred and nine patients who were treated for DR at the Zuckerberg San Francisco General Hospital retina clinic between 1 July 2015 and 30 January 2016 were enrolled in the study. Multivariate logistic regression analysis of demographic and medical information was used to determine independent risk factors for non-compliance to DR follow-up appointments.

RESULTS

The mean patient age was 58 years. Sixty-three percent (132/209) of patients were male; the mean haemoglobin A1c level was 8.5 (SD 0.14). Forty-six percent (97/209) of patients attended <80% of their DR follow-up appoinments. Independent risk factors for non-compliance after multivariate logistic regression analysis were diabetic foot involvement [OR: 2.40, 95% CI: (1.04-5.55)] and foot/kidney involvement [OR: 3.79 (1.35-10.5)], history of major depressive disorder (MDD) [OR: 2.11 (1.05-4.26), and having Medi-Cal [OR: 5.01 (2.00-12.5)] or SF Health insurance [OR: 6.79 (2.14-21.5)].

CONCLUSIONS AND RELEVANCE

In conclusion, this is the first study to identify diabetic end organ damage and MDD as independent risk factors for non-compliance in DR follow-up appointments. It is important that health care providers identify these patient subsets and increase efforts to more deliberately encourage follow-up in these high-risk patient groups for DR.

Association of ocular, cardiovascular, morphometric and lifestyle parameters with retinal nerve fibre layer thickness

Background

Glaucoma is a neurodegenerative disease, leading to thinning of the retinal nerve fibre layer (RNFL). The exact influence of ocular, cardiovascular, morphometric, lifestyle and cognitive factors on RNFL thickness (RNFLT) is unknown and was analysed in a subgroup of the Gutenberg Health Study (GHS).

Methods

Global peripapillary RNFLT was measured in 3224 eyes of 1973 subjects (49% female) using spectral-domain optical coherence tomography (SD-OCT). The association of age, sex, ocular, cardiovascular, morphometric, lifestyle and cognitive factors on RNFLT was analysed using Pearson correlation coefficient and fitting a linear mixed model.

Results

In the univariable analysis highest correlations were found for axial length (r = -0.27), spherical equivalent (r = 0.24), and glaucoma (r = -0.15) (p<0.0001, respectively). Other significant correlations with RNFLT were found for age, sex, intraocular pressure, systemic hypertension and systolic blood pressure, previous eye surgery, cholesterol, homocysteine, history of coronary artery disease, history of myocardial infarction, apnoea, diabetes and alcohol intake, p<0.05, respectively. Body length, body weight, BMI, diastolic blood pressure, blood glucose, HbA1c, history of apoplexy, cognitive function, peripheral artery disease, tinnitus, migraine, nicotine intake, central corneal thickness, and pseudophakia were not significantly correlated with RNFLT. The regression model revealed a significant relationship between RNFLT and age in decades (p<0.02), spherical equivalent (p<0.0001), axial length (p<0.0001), glaucoma (p<0.0001), tinnitus (p = 0.04), apnoea (p = 0.047), homocysteine (p = 0.05) and alcohol intake >10g/d for women and >20g/d for men (p = 0.02). Glaucoma, apnoea, higher homocysteine, higher alcohol intake and higher axial length as well as age were related to decreased RNFLT while higher spherical equivalent or history for tinnitus were related to thicker RNFL.

Conclusion

RNFLT is related to age, ocular parameters and lifestyle factors. Considering these parameters in normative databases could improve the evaluation of peripapillary RNFLT. It is necessary to evaluate if a reduction of alcohol intake as well as the therapy of apnea or high homocysteine levels could positively influence RNFLT.

Effect of duration and severity of migraine on retinal nerve fiber layer, ganglion cell layer, and choroidal thickness

Purpose:

To investigate the factors in migraine that have the highest significance on retinal and choroidal layers’ thickness.

Methods:

Ninety patients with migraine and 40 age-matched healthy participants were enrolled in this observational, cross-sectional study. After full ophthalmological examination, spectral domain-optical coherence tomography was done for all patients measuring the thickness of ganglion cell layer and retinal nerve fiber layer. Enhanced depth imaging technique was used to measure the choroidal thickness.

Results:

There was significant thinning in the superior and inferior ganglion cell layers, all retinal nerve fiber layer quadrants, and all choroidal quadrants (except for the central subfield) in migraineurs compared to controls. The duration of migraine was significantly correlated with ganglion cell layer, retinal nerve fiber layer, and all choroidal quadrants, while the severity of migraine was significantly correlated with ganglion cell layer and retinal nerve fiber layer only. Multiregression analysis showed that the duration of migraine is the most important determinant factor of the superior retinal nerve fiber layer quadrant (β = −0.375, p = 0.001) and in all the choroidal quadrants (β = −0.531, −0.692, −0.503, −0.461, −0.564, respectively, p  < 0.001), while severity is the most important determinant factor of inferior, nasal, and temporal retinal nerve fiber layer quadrants (β = −0.256, −0.335, −0.308; p  = 0.036, 0.005, 0.009, respectively) and the inferior ganglion cell layer hemisphere (β = −0.377 and p = 0.001).

Conclusion:

Ganglion cell layer, retinal nerve fiber layer, and choroidal thickness are significantly thinner in patients with migraine. The severity of migraine has more significant influence in the thinning of ganglion cell layer and retinal nerve fiber layer, while the duration of the disease affected the choroidal thickness more.

Optical Coherence Tomography in Patients with Chronic Migraine: Literature Review and Update

Migraine is a chronic disease characterized by unilateral, pulsating, and often moderate-to-severe recurrent episodes of headache with nausea and vomiting. It affects approximately 15% of the general population, yet the underlying pathophysiological mechanisms are not fully understood. Optical coherence tomography (OCT) is a safe and reproducible diagnostic technique that utilizes infrared wavelengths and has a sensitivity of 8–10 μm. It can be used to measure thinning of the retinal nerve fiber layer (RNFL) in some neurological disorders. Although ophthalmologists are often the first specialists to examine patients with migraine, few studies have addressed the involvement of the optic nerve and retino-choroidal structures in this group. We reviewed the literature on the etiological and pathological mechanisms of migraine and the relationship between recurrent constriction of cerebral and retrobulbar vessels and ischemic damage to the optic nerve, retina, and choroid. We also assessed the role of OCT for measuring peripapillary RNFL thickness and macular and choroidal changes in migraine patients. There is considerable evidence of cerebral and retrobulbar vascular involvement in the etiology of migraine. Transitory and recurrent constriction of the retinal and ciliary arteries may cause ischemic damage to the optic nerve, retina, and choroid in patients with migraine. OCT to assess the thickness of the peripapillary RNFL, macula, and choroid might increase our understanding of the pathophysiology of migraine and facilitate diagnosis of retino-choroidal compromise and follow-up of therapy in migraine patients. Future studies should determine the usefulness of OCT findings as a biomarker of migraine.