Photophobia Contributes to Migraine-Associated Disability and Reduced Work Productivity: Results From the American Registry for Migraine Research (ARMR)

BACKGROUND

Photosensitivity, often called "photophobia" in the migraine literature, is a common and bothersome symptom for most people during their migraine attacks. This study aimed to investigate the association of photophobia severity with work productivity, activity impairment, and migraine-associated disability using data from a large cohort of patients with migraine who were enrolled into the American Registry for Migraine Research (ARMR).

METHODS

This study used Photosensitivity Assessment Questionnaire (PAQ) scores to investigate the relationship between photophobia severity with work productivity and activity impairment (using the Work Productivity and Activity Impairment [WPAI] questionnaire) and migraine-related disability (using the Migraine Disability Assessment [MIDAS]) among those with migraine. Summary statistics are presented as means and standard deviations for variables that were normally distributed and as medians and interquartile ranges for variables that were not normally distributed. Multiple linear regression models were developed to measure the relationships between photophobia scores with work productivity and activity impairment and migraine-associated disability, controlling for age, sex, headache frequency, headache intensity, anxiety (using the generalized anxiety disorder [GAD-7]), and depression (using the Patient Health Questionnaire [PHQ-2]).

RESULTS

One thousand eighty-four participants were included. Average age was 46.1 (SD 13.8) years, 87.2% (n = 945) were female, average headache frequency during the previous 90 days was 44.3 (SD 29.9), average headache intensity was 5.9 (SD 1.7), median PHQ-2 score was 1 (IQR 0-2), and median GAD-7 was 5 (IQR 2-8). Mean PAQ score was 0.47 (SD 0.32), and median MIDAS score was 38 (IQR 15.0-80.0). Among the 584 employed participants, 47.4% (n = 277) reported missing work in the past week because of migraine, mean overall work impairment was 42.8% (SD 26.7), mean activity impairment was 42.5% (SD 26.2), mean presenteeism score was 38.4% (SD 24.4), and median absenteeism was 0 (IQR 0-14.5). After controlling for age, sex, headache frequency, average headache intensity, PHQ-2 score, and GAD-7 score, there was a statistically significant association between photophobia scores with: a) MIDAS scores (F[7,1028] = 127.42, P < 0.001, R 2 = 0.461, n = 1,036); b) overall work impairment (F[7,570] = 29.23, P < 0.001, R 2 = 0.255, n = 578); c) activity impairment (F[7,570] = 27.42, P < 0.001, R 2 = 0.243, n = 578); d) presenteeism (F[7,570] = 29.17, P < 0.001, R 2 = 0.255, n = 578); and e) absenteeism for the zero-inflated ( P = 0.003) and negative binomial ( P = 0.045) model components ( P < 0.001, n = 578).

CONCLUSIONS

In those with migraine, severe photophobia is associated with reduced work productivity and higher presenteeism, absenteeism, activity impairment, and migraine-related disability.

Extrasynaptic δGABAA receptors mediate resistance to migraine-like phenotype in rats

BACKGROUND

GABA, a key inhibitory neurotransmitter, has synaptic and extrasynaptic receptors on the postsynaptic neuron. Background GABA, which spills over from the synaptic cleft, acts on extrasynaptic delta subunit containing GABAA receptors. The role of extrasynaptic GABAergic input in migraine is unknown. We investigated the susceptibility to valid migraine-provoking substances with clinically relevant behavioral readouts in Genetic Absence Epilepsy of Rats Strasbourg (GAERS), in which the GABAergic tonus was altered. Subsequently, we screened relevant GABAergic mechanisms in Wistar rats by pharmacological means to identify the mechanisms.

METHODS

Wistar and GAERS rats were administered nitroglycerin (10 mg/kg) or levcromakalim (1 mg/kg). Mechanical allodynia and photophobia were assessed using von Frey monofilaments and a dark-light box. Effects of GAT-1 blocker tiagabine (5 mg/kg), GABAB receptor agonist baclofen (2 mg/kg), synaptic GABAA receptor agonist diazepam (1 mg/kg), extrasynaptic GABAA receptor agonists gaboxadol (4 mg/kg), and muscimol (0.75 mg/kg), T-type calcium channel blocker ethosuximide (100 mg/kg) or synaptic GABAA receptor antagonist flumazenil (15 mg/kg) on levcromakalim-induced migraine phenotype were screened.

RESULTS

Unlike Wistar rats, GAERS exhibited no reduction in mechanical pain thresholds or light aversion following nitroglycerin or levcromakalim injection. Ethosuximide did not reverse the resistant phenotype in GAERS, excluding the role of T-type calcium channel dysfunction in this phenomenon. Tiagabine prevented levcromakalim-induced mechanical allodynia in Wistar rats, suggesting a key role in enhanced GABA spillover. Baclofen did not alleviate mechanical allodynia. Diazepam failed to mitigate levcromakalim-induced migraine phenotype. Additionally, the resistant phenotype in GAERS was not affected by flumazenil. Extrasynaptic GABAA receptor agonists gaboxadol and muscimol inhibited periorbital allodynia in Wistar rats.

CONCLUSION

Our study introduced a rat strain resistant to migraine-provoking agents and signified a critical involvement of extrasynaptic δGABAergic receptors. Extrasynaptic δ GABAA receptors, by mediating constant background inhibition on the excitability of neurons, stand as a novel drug target with a therapeutic potential in migraine.

THE LOSS OF INFRARED LIGHT SENSITIVITY OF PHOTORECEPTOR CELLS MEASURED WITH TWO-PHOTON EXCITATION AS AN INDICATOR OF DIABETIC RETINOPATHY: A Pilot Study

PURPOSE

Human photoreceptors are sensitive to infrared light (IR). This sensitivity can be used as a novel indicator of retinal function. Diabetic retinopathy patients were assessed using in vivo two-photon excitation and compared their scotopic IR threshold with that of healthy patients.

METHODS

Sixty-two participants, 28 healthy and 34 with diabetic retinopathy, underwent a comprehensive eye examination, where visual acuity and contrast sensitivity were assessed. Infrared thresholds were measured in the fovea and parafovea following 30-minute dark adaptation. A two-photon excitation device was used with integrated pulsed laser light (1,045 nm) for sensitivity testing and scanning laser ophthalmoscopy for fundus imaging.

RESULTS

The mean Snellen visual acuity of diabetic patients (6/7.7) was worse than that of the healthy patients (6/5.5), which was significantly different (P < 0.001). Disease patients had decreased contrast sensitivity, especially at 6 and 18 cycles/degree. The mean retinal sensitivity to IR light in eyes with diabetic retinopathy (11.6 ± 2.0 dB) was significantly (P < 0.001) lower than that in normal eyes (15.5 ± 1.3 dB).

CONCLUSION

Compared with healthy control subjects, the IR light sensitivity of diabetic patients was significantly impaired. Two-photon measurements can be used in the assessment of retinal disease, but further studies are needed to validate IR light stimulation in various stages of diabetic retinopathy.

Photophobia: shared pathophysiology underlying dry eye disease, migraine and traumatic brain injury leading to central neuroplasticity of the trigeminothalamic pathway

BACKGROUND

Photophobia is a potentially debilitating symptom often found in dry eye disease (DE), migraine and traumatic brain injury (TBI).

METHODS

We conducted a review of the literature via a PubMed search of English language articles with a focus on how photophobia may relate to a shared pathophysiology across DE, migraine and TBI.

RESULTS

DE, migraine and TBI are common conditions in the general population, are often comorbid, and share photophobia as a symptom. Across the three conditions, neural dysregulation of peripheral and central nervous system components is implicated in photophobia in various animal models and in humans. Enhanced activity of the neuropeptide calcitonin gene-related peptide (CGRP) is closely linked to photophobia. Current therapies for photophobia include glasses which shield the eyes from specific wavelengths, botulinum toxin, and inhibition of CGRP and its receptor. Many individuals have persistent photophobia despite the use of these therapies, and thus, development of new therapies is needed.

CONCLUSIONS

The presence of photophobia in DE, migraine and TBI suggests shared trigeminothalamic pathophysiologic mechanisms, as explained by central neuroplasticity and hypersensitivity mediated by neuropeptide CGRP. Treatment strategies which target neural pathways (ie, oral neuromodulators, transcutaneous nerve stimulation) should be considered in patients with persistent photophobia, specifically in individuals with DE whose symptoms are not controlled with traditional therapies.

Neurobiology of Photophobia

BACKGROUND

Photophobia is commonly associated with migraine, meningitis, concussion, and a variety of ocular diseases. Advances in our ability to trace multiple brain pathways through which light information is processed have paved the way to a better understanding of the neurobiology of photophobia and the complexity of the symptoms triggered by light.

PURPOSE

The purpose of this review is to summarize recent anatomical and physiological studies on the neurobiology of photophobia with emphasis on migraine.

RECENT FINDINGS

Observations made in blind and seeing migraine patients, and in a variety of animal models, have led to the discovery of a novel retino-thalamo-cortical pathway that carries photic signal from melanopsinergic and nonmelanopsinergic retinal ganglion cells (RGCs) to thalamic neurons. Activity of these neurons is driven by migraine and their axonal projections convey signals about headache and light to multiple cortical areas involved in the generation of common migraine symptoms. Novel projections of RGCs into previously unidentified hypothalamic neurons that regulate parasympathetic and sympathetic functions have also been discovered. Finally, recent work has led to a novel understanding of color preference in migraine-type photophobia and of the roles played by the retina, thalamus, and cortex.

SUMMARY

The findings provide a neural substrate for understanding the complexity of aversion to light in patients with migraine and neuro-ophthalmologic other disorders.

Psychiatric comorbidities and photophobia in patients with migraine

BACKGROUND

Based on recent findings and our own impressions we took a closer look at the relationship between (inter)ictal photophobia and psychometric variables in migraine patients with photophobia.

FINDINGS

For this study we included 29 (27 female) migraine patients and 31 (18 female) controls with a mean age of 31.6 ± 12.5 years and 24.0 ± 4.1 years, respectively. All participants filled out the Depression Anxiety Stress Scale (DASS). Interictal photophobia in patients was significantly higher than photophobia in controls (p = .001). Patients showed statistically significantly higher levels of depressive symptoms (p < .001), anxiety symptoms (p < .001) and stress (p < .001) than controls. Among all participants, (interictal) photophobia correlated positively with age (rho = .318, p = .013) as well as with the levels of depressive symptoms (rho = .459, p < .001), anxiety symptoms (rho = .346, p = .008) and stress (rho = .368, p = .005), but not with gender. In the patients, ictal photophobia correlated positively with age (rho = .473, p = .01) and interictal photophobia (rho = .423, p = .022). Linear regression analysis revealed only a trend towards statistical significance for (interictal) photophobia as a predictor for the level of depressive symptoms (rho = .457, p = 0.056) in the whole sample.

CONCLUSIONS

Considering higher levels of photophobia in depression and the comorbidity of migraine and depression, it might be possible that depression contributes to interictal photophobia in patients with migraine. The same may be true for anxiety and stress. Both are also related to migraine and their possible impact on photophobia in migraine may be explained by pupillary dysfunction.

Altered pupillary light response scales with disease severity in migrainous photophobia

Background Autonomic dysfunction and light sensitivity are core features of the migraine attack. Growing evidence also suggests changes in these parameters between attacks. Though sensory and autonomic responses likely interact, they have not been studied together across the spectrum of disease in migraine. Methods We performed digital infrared pupillometry while collecting interictal photophobia thresholds (PPT) in 36 migraineurs (14 episodic; 12 chronic; 10 probable) and 24 age and sex-matched non-headache controls. Quantitative pupillary light reflexes (PLR) were assessed in a subset of subjects, allowing distinction of sympathetic vs parasympathetic pupillary function. A structured questionnaire was used to ascertain migraine diagnosis, headache severity, and affective symptoms. Results Photophobia thresholds were significantly lower in migraineurs than controls, and were lowest in chronic migraine, consistent with a disease-related gradient. Lower PPT correlated with smaller dark-adapted pupil size and larger end pupil size at PPT, which corresponded to a reduced diameter change. On PLR testing, measures of both parasympathetic constriction and sympathetic re-dilation were reduced in migraineurs with clinically severe migraine. Conclusions In summary, we show that severity of photophobia in migraine scales with disease severity, in association with shifts in pupillary light responses. These alterations suggest centrally mediated autonomic adaptations to chronic light sensitivity.

Melatonin Secretion is Supersensitive to Light in Migraine

The present study examined the sensitivity to light of melatonin (MLT) secretion in familial migraine during a headache-free interval. Twelve female patients and 12 healthy controls were included in the trial. All subjects were studied twice. In each session, light exposure (300 lx) or placebo was randomly administered for 30 min between 00.30 and 01.00 h. Blood was sampled hourly between 20.00 and 24.00 h, and 02.00 and 04.00 h and every 15 min between 00.30 and 01.30 h. Plasma MLT levels were determined by radioimmunoassay. MLT suppression was more marked in the migraine group than in the control group [difference of area under curve (δAUC) = −53.8 ± 16.2 vs. 18.5 ± 12.7 pg/h/ml, P < 0.005; maximum of MLT suppression (δ) = −35.7 ± 10.2 vs.- 6.7 ± 5.8 pg/ml, P < 0.05]. These findings show a clear hypersensitivity to light in young female migraineurs during the headache-free period.

Photophobia in a blind eye after removal of a progressive orbital optic glioma with denervation

Optic glioma (OPG) accounts for 4-8% of all brain tumors in children. En-block removal of intraorbital tumor is recommended in cases with disfiguring exophthalmos and impaired vision. Surgical resection of intraorbital optic nerve (ON) poses the risks of permanent ptosis and globe atrophy. We present here the case of a 4-year-old boy with exophthalmos and near blindness due to an intraorbital OPG. Despite chemotherapy he showed progressive exophthalmos and vision loss. Bony orbital decompression with ON transection temporally reduced his exophthalmos. OPG resection was required later for recurrence of his exophthalmos secondary to tumor progression. Post operatively, he had preserved oculomotor nerve functions but developed globe ischemia. Unusually, his ischemic globe caused him to have pain and severe photophobia, which later lead to enucleation. Photophobia has been reported in blind patients. Animal models and MRI functional imaging showed activation of trigeminal pathway during photophobia in completely transected ON. However, the exact neuro-ophthalmology pathway requires further study.

CONCLUSION

This is the first described case of photophobia after excision of OPG with ON denervation. Photophobia can be a serious side effect that significantly lowers the patient's quality of life.

[CHARACTERIZATION OF VESTIBULAR DISORDERS IN THE INJURED PERSONS WITH THE BRAIN CONCUSSION IN ACUTE PERIOD]

There were examined 32 injured persons, ageing (34.1 ± 1.3) yrs at average, for the brain commotion (BC). The adopted protocol SCAT-3 (Standardized Concussion Assessment Tool, 3rd ed.), DHI (Dizziness Handicap Inventory questionnaire), computer stabilography (KS) were applied for the vestibular disorders diagnosis. There was established, that in acute period of BC a dyssociation between regression of objective neurological symptoms and permanence of the BC indices occurs, what confirms a latent disorder of the balance function. Changes of basic indices of statokinesiography, including increase of the vibration amplitude enhancement in general centre of pressure in a saggital square and the BC square (235.3 ± 13.7) mm2 in a modified functional test of Romberg with the closed eyes is possible to apply as objective criteria for the BC diagnosis.

Elevated audiovisual temporal interaction in patients with migraine without aura

BACKGROUND

Photophobia and phonophobia are the most prominent symptoms in patients with migraine without aura. Hypersensitivity to visual stimuli can lead to greater hypersensitivity to auditory stimuli, which suggests that the interaction between visual and auditory stimuli may play an important role in the pathogenesis of migraine. However, audiovisual temporal interactions in migraine have not been well studied. Therefore, our aim was to examine auditory and visual interactions in migraine.

METHODS

In this study, visual, auditory, and audiovisual stimuli with different temporal intervals between the visual and auditory stimuli were randomly presented to the left or right hemispace. During this time, the participants were asked to respond promptly to target stimuli. We used cumulative distribution functions to analyze the response times as a measure of audiovisual integration.

RESULTS

Our results showed that audiovisual integration was significantly elevated in the migraineurs compared with the normal controls (p < 0.05); however, audiovisual suppression was weaker in the migraineurs compared with the normal controls (p < 0.05).

CONCLUSIONS

Our findings further objectively support the notion that migraineurs without aura are hypersensitive to external visual and auditory stimuli. Our study offers a new quantitative and objective method to evaluate hypersensitivity to audio-visual stimuli in patients with migraine.

Central sensitization in photophobic and non-photophobic migraineurs: possible role of retino nuclear way in the central sensitization process

The aim of the present study was to investigate the possible relationships between the presence of headache-related photophobia and migraine-associated allodynia--a hallmark of central sensitization--among patients with different migraine types. A sample of 456 migraineurs was studied. Our results showed that photophobia was present in a high proportion of patients, with similar figures in patients with episodic migraine or CM, and confirmed that the prevalence of allodynia was higher among CM patients than in those with episodic migraine. We found a clear association between migraine-related allodynia and photophobia only in CM patients. Overall, these findings suggest that light stimulation may contribute to central sensitization of pain pathways in migraineurs, possibly contributing to progression into chronic forms. The possible connections underlying this type of sensitization is offered by the recently published data on a non-image-forming visual retino-thalamo-cortical pathway which may allow photic signals to converge on a thalamic region which is selectively activated during migraine headache.

Correlation of visual quality with satisfaction and function in a normal cohort of pseudophakic patients

PURPOSE

To select a normal post-cataract-surgery cohort, determine visual quality parameters, and compare these parameters with self-reported satisfaction and visual function.

SETTING

John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA.

DESIGN

Retrospective cohort study.

METHODS

A cohort of pseudophakic patients was selected based on uneventful surgery, good corrected visual acuity (no worse than logMAR 0.02), and lack of ocular complaints or pathology including dry-eye syndrome or posterior capsule opacification. A single-piece high-refractive-index acrylic intraocular lens, age 50 or older, and at least 1 year out from surgery were other inclusion criteria. Testing included logMAR corrected distance visual acuity (CDVA), mesopic 10% contrast logMAR CDVA with and without glare, straylight determination, Rasch-modified National Eye Institute Visual Function questionnaire 11R (NEI VF-11R), custom pseudophakic dysphotopsia survey, and overall satisfaction question. Correlations were determined between these parameters.

RESULTS

Of the 2953 patients considered, 70 patients met all criteria, provided consent, and enrolled. Only pseudophakic dysphotopsia (r = -0.60; P<.0001) and the NEI VF-11R (r = -0.44; P<.0001) correlated with overall satisfaction. In addition, pseudophakic dysphotopsia correlated with the NEI VF-11R (r = 0.58; P<.0001).

CONCLUSIONS

When evaluating a highly controlled population with expected high satisfaction after cataract surgery, pseudophakic dysphotopsia was clearly the only significant dissatisfier. Furthermore, dysphotopsia highly correlated with the NEI VF-11R questionnaire; thus, symptoms of dysphotopsia are also seen to have functional significance. A shortened NEI VFQ survey and satisfaction correlated strongly with the full survey.

Photophobia measurement in intermittent exotropia using the contrast sensitivity test

BACKGROUND

To assess the presence and extent of photophobia in children with intermittent exotropia (X[T]) using the contrast sensitivity test.

METHODS

Fifty-eight children with X(T) and 34 normal controls were studied with the functional acuity contrast test. Each participant viewed the stimuli of contrast monocularly and binocularly under photopic and mesopic conditions, performed with and without glare. Photophobia was defined as a reduction of contrast sensitivity caused by glare light. We compared the photophobia of children with X(T) to that of normal controls, and to the photophobia 3 months after muscle surgery.

RESULTS

With stimuli of glare, the contrast sensitivity of children with X(T) was suppressed at intermediate spatial frequencies under mesopic condition (p = 0.006 for 6 cycles per degree [cpd], p = 0.027 for 12 cpd), whereas that of normal controls showed no difference. It occurred when X(T) patients viewed targets binocularly, and significantly improved after strabismus surgery (p = 0.003 at 6 cpd). The measured photophobia of X(T) was strongly correlated to the photophobia symptoms reported by parents (p = 0.002).

CONCLUSIONS

The mesopic contrast sensitivity with glare can represent the photophobia of children with X(T). Contrast sensitivity may be a useful measure for monitoring symptoms related to X(T).

Shedding light on photophobia

Photophobia is a common yet debilitating symptom seen in many ophthalmic and neurologic disorders. Despite its prevalence, it is poorly understood and difficult to treat. However, the past few years have seen significant advances in our understanding of this symptom. We review the clinical characteristics and disorders associated with photophobia, discuss the anatomy and physiology of this phenomenon, and conclude with a practical approach to diagnosis and treatment.

What initiates a migraine attack? Conclusions from four longitudinal studies of quantitative EEG and steady-state visual-evoked potentials in migraineurs

OBJECTIVES

Quantitative electroencephalograpic (QEEG) frequency spectra and steady-state visual-evoked potentials (SSVEP) are indicators of corticothalamic excitability (e.g., arousal). Increased interictal excitability is suggested to be an important element in the migraine pathophysiology. In this paper, we summarize our results from four studies of QEEG and SSVEP recordings in migraineurs interictally and in the days before an attack with the intention to shed light on attack-initiating mechanisms.

MATERIAL AND METHODS

Thirty-two healthy controls, 33 migraineurs without and eight with aura each had three EEGs with photic stimulation on different days. Using the patient headache diaries, we classified the recordings as interictal, preictal, ictal, or post-ictal retrospectively. Interictal recordings were compared pairwise with attack-related EEGs from the same patient as well as with control EEGs. We also correlated clinical variables with the QEEG and SSVEP data.

RESULTS

Between attacks, we found increased relative theta activity and attenuated medium-frequency photic responses in migraineurs without aura compared with those in controls. Within 36 h before the attack, slow and asymmetric EEG activity developed. Increased trigger sensitivity and photophobia correlated with higher theta power and depressed photic responses. Attack duration, migraine history duration, and pain intensity were associated with EEG slowing.

CONCLUSIONS

A general tendency toward EEG slowing and depression of photic responses characterized the migraine group. This pattern was also related to increased severity of symptoms. A change in cortical activity occurred within 36 h before attacks. Our results indicate that thalamocortical hypoexcitability is associated with attack initiation and sensory hypersensitivity in migraine.

Determining of migraine prognosis using latent growth mixture models

BACKGROUND

This paper presents a retrospective study to classify patients into subtypes of the treatment according to baseline and longitudinally observed values considering heterogenity in migraine prognosis. In the classical prospective clinical studies, participants are classified with respect to baseline status and followed within a certain time period. However, latent growth mixture model is the most suitable method, which considers the population heterogenity and is not affected drop-outs if they are missing at random. Hence, we planned this comprehensive study to identify prognostic factors in migraine.

METHODS

The study data have been based on a 10-year computer-based follow-up data of Mersin University Headache Outpatient Department. The developmental trajectories within subgroups were described for the severity, frequency, and duration of headache separately and the probabilities of each subgroup were estimated by using latent growth mixture models. SAS PROC TRAJ procedures, semiparametric and group-based mixture modeling approach, were applied to define the developmental trajectories.

RESULTS

While the three-group model for the severity (mild, moderate, severe) and frequency (low, medium, high) of headache appeared to be appropriate, the four-group model for the duration (low, medium, high, extremely high) was more suitable. The severity of headache increased in the patients with nausea, vomiting, photophobia and phonophobia. The frequency of headache was especially related with increasing age and unilateral pain. Nausea and photophobia were also related with headache duration.

CONCLUSIONS

Nausea, vomiting and photophobia were the most significant factors to identify developmental trajectories. The remission time was not the same for the severity, frequency, and duration of headache.

Novel CNGA3 and CNGB3 mutations in two Pakistani families with achromatopsia

PURPOSE

To identify the genetic defect in two Pakistani families with autosomal recessive achromatopsia.

METHODS

Two families (RP26 and RP44) were originally diagnosed with retinal dystrophy based upon their medical history. To localize the causative genes in these families, homozygosity mapping was performed using Affymetrix 10K single nucleotide polymorphism (SNP) arrays. Sequence analysis was used to find the mutations in candidate genes cyclic nucleotide-gated channel alpha-3 (CNGA3; family RP26) and cyclic nucleotide-gated channel beta-3 (CNGB3; family RP44). Control individuals were analyzed by allele-specific PCR for the CNGA3 mutation and BstXI restriction analysis for the CNGB3 mutation. After genetic analysis, clinical diagnosis was re-evaluated by electroretinography and color vision testing. During the course of this study, selected affected members of family RP26 were given pink glasses as supportive therapy.

RESULTS

Sequence analysis of the positional candidate genes identified a novel missense mutation in CNGA3 (c.822G>T; p.R274S) in family RP26, and a novel CNGB3 frameshift mutation (c.1825delG; p.V609WfsX9) in family RP44. Clinical re-evaluation after genetic analysis revealed that both families have segregating autosomal recessive achromatopsia.

CONCLUSIONS

Genetic analysis of two Pakistani families with retinal disease enabled the establishment of the correct diagnosis of achromatopsia. Two novel mutations were identified in CNGA3 and CNGB3 that are both specifically expressed in cone photoreceptors. Re-evaluation of the clinical status revealed that both families had achromatopsia. The use of pink glasses in patients was helpful in reducing photophobia and enabled rod-mediated vision.

Visual evoked potential and spatial frequency in migraine: a longitudinal study

OBJECTIVES

Reduced habituation of visual evoked potentials (VEP) has been reported in migraine. We aimed to study if preattack excitability changes were related to check size using a paired longitudinal design.

MATERIALS AND METHODS

Magnocellular and parvocellular functions were studied with monocular 31 and 62 checks in 33 adult migraine patients without aura (MwoA), 8 with aura (MA) and 31 controls. VEP was recorded in four blocks of 50 stimuli. N1P1 and P1N2 amplitudes were measured. Sessions were classified as preattack or interictal.

RESULTS

MA patients had significantly higher P1N2 and N1P1 amplitude than the controls and MwoA. VEP amplitude habituation was not found in controls. Migraine patients had significantly higher P1N2 amplitude before the attack compared with a paired interictal recording for large checks.

CONCLUSIONS

Cortical excitability is high in MA. Headache severity affects visual excitability. Increased P1N2 VEP amplitude before the attack suggests a cyclic decreased intracortical inhibition in extrastriate magnocellular pathways in migraine.

[Neuro-ophthalmological manifestations of pituitary adenomas. The usefulness of optical coherence tomography]

INTRODUCTION

Pituitary adenomas are a frequently occurring pathology that require multidisciplinary management by several different specialists. Their neuro-ophthalmological manifestations vary widely and sometimes appear as the presenting symptom.

AIM

To gather the main ophthalmological signs and symptoms of these tumours so that specialists who find themselves before any of them will suspect this pathology.

DEVELOPMENT

This survey was based on the clinical experience of the neuro-ophthalmological unit at the Hospital Clinic de Barcelona, with over 350 patients who had suffered from pituitary tumours. A bibliographical search was also carried out on Medline for papers published on pituitary adenomas in the literature in both English and Spanish. We focused mainly on those that reported on the ophthalmological manifestations of such tumours. A number of articles were found dealing with isolated ophthalmological manifestations of these tumours, many of them as presenting symptoms. We also found review articles in English. Apart from oculomotor disorders and other less common findings, visual field defects stand out as the guiding symptom of this condition.

CONCLUSIONS

Improved diagnostic techniques are allowing pituitary tumours to be detected at increasingly earlier stages, but cases are still seen with neuro-ophthalmological symptoms as the presenting symptoms. Familiarity with these syndromes is crucial. In addition to the clinical and visual field examination, optical coherence tomography is particularly useful for the diagnosis and follow-up of these patients. Prospective studies are needed to establish factors for predicting the visual recovery in these patients.

Update on blepharospasm: report from the BEBRF International Workshop

This review updates understanding and research on blepharospasm, a subtype of focal dystonia. Topics covered include clinical aspects, pathology, pathophysiology, animal models, dry eye, photophobia, epidemiology, genetics, and treatment. Blepharospasm should be differentiated from apraxia of eyelid opening. New insights into pathology and pathophysiology are derived from different types of imaging, including magnetic resonance studies. Physiologic studies indicate increased plasticity and trigeminal sensitization. While botulinum neurotoxin injections are the mainstay of therapy, other therapies are on the horizon.

Retinal sensitivity loss and structural disturbance in areas of capillary nonperfusion of eyes with diabetic retinopathy

PURPOSE

To assess light sensitivity and morphologic changes of capillary nonperfused areas in diabetic retinopathy.

DESIGN

Prospective, observational cross-sectional study.

METHODS

Seventeen consecutive patients (20 eyes) with areas of capillary nonperfusion resulting from severe nonproliferative or proliferative diabetic retinopathy were included in the study. All eyes underwent fluorescent angiography and fundus-related microperimetry. Nonperfused areas of the retina were scanned with optical coherence tomography (OCT).

RESULTS

In all 20 diabetic eyes, areas of capillary nonperfusion detected by fluorescein angiography were associated with the loss of retinal sensitivity. At the edges of the nonperfused area, retinal sensitivity tended to be reduced. The OCT images suggested a structural disturbance of the inner retina and high-reflectivity deposition located between the outer segments of photoreceptor and the retinal pigment epithelium corresponding to the areas of capillary nonperfusion.

CONCLUSIONS

Areas of capillary nonperfusion resulting from severe nonproliferative or proliferative diabetic retinopathy show morphologic changes of the retinal structure, which may lead to a loss of sensitivity.

Impairment in Color Perception in Migraine With and Without Aura

OBJECTIVE

To assess visual perception in 40 patients suffering from migraine with aura (MA), 40 patients suffering from migraine without aura (MO), and 40 controls.

BACKGROUND

Visual perception abnormalities are a common feature in both MA and MO.

METHODS

We performed luminance and color central perimetry. Black and white pattern reversal visual-evoked potentials were also assessed.

RESULTS

Luminance perimetry was similar in patients and controls. Color perimetry instead revealed an impairment in the perception of red ("quantitative perception index") in migraine patients; this impairment was more pronounced in patients with MA (P < .001) than in those with MO (P < .05) and was related to the degree of photophobia recorded before testing. A subgroup of MO patients who had a migraine attack shortly after being tested also displayed a marked impairment in the perception of blue. This subgroup of patients had a statistically significant (P < .001) lower perception of blue than the rest of the MO patients, who had a migraine attack later; they also had a high degree of unpleasant perceptions after testing. Black and white visual evoked potentials were similar in patients and controls.

CONCLUSION

The impairment in visual perception of red, which was more marked in MA than in MO patients, may be related to the degree of photophobia recorded before testing. The reduced perception of blue, which only occurred in a subgroup of MO patients in the premonitory phase of the migraine attack, probably occurs through mechanisms that involve dopaminergic function. We cannot exclude the possibility that the visual stimulations induced the migraine attack in this subgroup of MO patients shortly after they were tested.

Amniotic membrane transplantation for painful bullous keratopathy

PURPOSE

To establish the effectiveness of amniotic membrane transplantation (AMT) in relieving pain and discomfort in patients with painful bullous keratopathy and its role in improving vision in eyes with visual potential.

METHODS

Seven eyes of seven consecutive patients with painful corneal conditions were included in a retrospective interventional noncomparative case series performed at Maidstone General hospital, Maidstone, UK. Amniotic membrane transplantation was performed in seven eyes. Pain relief, epithelial healing, and visual changes were evaluated. Pain relief and freedom from discomfort were considered for the success of the surgery.

RESULTS

The mean follow-up was 26.57 weeks (range 11 to 53 weeks). Pain relief was achieved in all seven (100%) eyes. Associated symptoms including foreign body sensation, photophobia, and tearing subsided significantly in all patients starting soon after the first postoperative day. Vision improved in 5 (71.42%) patients.

CONCLUSIONS

AMT is an effective alternative for the management of patients with painful bullous eratopathy. Besides pain relief and reduction of ocular inflammation it remains unclear whether this procedure can also be used to improve vision in eyes with visual potential.

[Comparative action of melatonin and bilobil on light perception and psychophysiological indices in patients with cerebral trauma anamnesis]

Pineal hormone melatonin (melaxen preparation) and a typical cognitive enhancer Ginkgo biloba (bilobil preparation) decreased the retinal light sensitivity thresholds upon two-week administration in young (aged 19-23) patients with cerebral trauma anamnesis. This effect was more significant in evening than in the morning hours. Both drugs also attenuated the reactive anxiety (bilobil was slightly superior to melaxen in this respect) and insignificantly increased the volume of acoustic memory. The observed similarity of the psychotropic effect of two preparations allows melatonin to be classified into nootropic agents.

Macular pigment optical density and photophobia light threshold

Light absorption by macular pigment may attenuate visual discomfort, or photophobia, for targets composed of short-wavelength light. Macular pigment optical density (MPOD) and photophobia light thresholds were measured psychophysically in 10 subjects. The energy necessary to induce photophobia for a short-wavelength target relative to a long-wavelength target was linearly related to MPOD, as well as estimates of peak MPOD and integrated macular pigment. In four subjects who consumed lutein supplements, increases in MPOD corresponded to increases in photophobia light thresholds. Light absorption by macular pigment appears to influence the amount of short-wavelength light necessary to elicit photophobia.

[Changes of retinal light sensitivity after YAG-laser capsulotomy]

BACKGROUND

The aim of this prospective study was firstly to investigate the changes of retinal light sensitivity of the central visual field in patients with posterior capsule opacification (PCO) after YAG-laser capsulotomy and secondly to determine the correlation between changes in retinal light sensitivity and patient's age and the diameter of posterior laser capsulotomy.

PATIENTS AND METHODS

Our study includes 25 eyes (25 patients) with PCO after phacoemulsification and intraocular lens implantation. In all patients YAG-laser capsulotomy was performed. In all patients, a threshold visual field analysis was carried out with the C 30 - 2 programme of the automated Humphrey Field Analyzer before and one month after the procedure.

RESULTS

In all patients a significant improvement of visual acuity was observed one month after capsulotomy (p = 0,00003). One month after YAG-laser treatment, a significant improvement of retinal light sensitivity in the central visual field was also observed. The average MD (mean deviation) before the procedure was - 6.05 db (+/- 3.2, max. - 11.7, min. + 2.17) and after the procedure - 3.61 db (+/- 3.7, max. - 10.87, min. + 0.71). Before laser capsulotomy obvious areas of reduced retinal sensitivity in 19 of 25 eyes (76 %) were found with MD p values of less than 5 %. One month after the procedure the MD p values were less than 5 % only in 8 eyes (32 %). The improvement in MD was statistically significant (p = 0,0002). No correlation was established between the improvement of retinal light sensitivity and patient's age or the size of the capsulotomy.

CONCLUSIONS

Our study shows that the improvement of retinal light sensitivity is significant after YAG-laser capsulotomy and not depends on patient age or capsulotomy size.

Specific features of migraine syndrome in children

The aim of the study was to define factors that can be used to distinguish migraine headaches from primary non-migraine headaches. Specific characteristics of headaches were analysed in 30,636 children aged 3-17; 18.97% had recurrent primary non-migraine headaches, whereas 8.63% had migraine headaches. Migraine attacks follow identical patterns (94.9%): occurring monthly (78.0%), occurring in morning hours (58.5%), lasting for several hours (45.1%) and ending after sleep (76.7%). Nausea, vomiting impulse and vomiting are basic present elements of migraine attacks in children. Canonical discriminate analysis defined the following statistically significant factors, which can distinguish migraine headaches from primary non-migraine headaches in children: relief after sleep (0.945), vomiting impulse (0.945), photophobia (0.523), nausea (0.379), phonophobia (0.354) and vomiting (0.330).

The evaluation of light sensitivity in benign essential blepharospasm

PURPOSE

To test light sensitivity thresholds rigorously in patients with benign essential blepharospasm (BEB) compared with patients who have known light sensitivity (migraineurs) and to normal control subjects.

DESIGN

Prospective, observational, case control study.

METHODS

We recruited a total of 87 subjects into each of three groups: BEB, migraine, and normal control subjects. A modified slit-lamp chin rest, heat shield, light meter, and halogen light that was modulated by a rheostat were used to measure light sensitivity thresholds. Participants were tested without spectacles, with gray-tinted spectacles, and with FL-41-tinted spectacles.

RESULTS

Light discomfort thresholds for subjects with BEB were significantly lower compared with normal control subjects (P < or = .009) and similar to the migraine group. Both gray and FL-41-tinted lenses improved light sensitivity thresholds in all groups (P < or = .0005). There was no observed difference in the improvement in light sensitivity when the gray and FL-41-tinted lenses were compared.

CONCLUSION

Patients with BEB are considerably more sensitive to light than control subjects and as sensitive to light as patients with migraine. Physicians who care for patients with BEB should consider using tinted lenses to help ameliorate symptoms.

Salivary cortisol and self-reported stress among persons with environmental annoyance

OBJECTIVES

Increased vulnerability to stress has been suggested as a possible mechanism behind medically unexplained conditions such as sensitivity to electricity and common smells. This study examined whether subjective environmental annoyance among the general population is associated with increased physiological reactivity or subjective stress scores.

METHODS

Four groups were studied (N=141): an electrically annoyed (N=17), a smell-annoyed (N=29), and a generally annoyed group (N=39) and a reference group matched for age, gender, and socioeconomic status (N=56). Over 5 days, the participants collected saliva for cortisol determination at awakening, 30 minutes after awakening, 8 hours after awakening, and at 9 o'clock in the evening. On the evening preceding the fifth day, the participants ingested a 0.5-mg dexamethasone tablet so that possible differential suppression of the hypothalamic-pituitary-adrenal (HPA) axis could be assessed. Each day, the participants also rated their subjective stress and health complaints.

RESULTS

No significant differences were found between the groups regarding cortisol secretion over 5 days. The dexamethasone suppression test showed inhibited cortisol secretion in all four groups. No associations were found between the cortisol concentrations and the self-reported stress scores or subjective health complaints.

CONCLUSIONS

Although the environmentally annoyed groups showed no signs of increased HPA-axis activation, being annoyed by both electrical devices and smells seems to be related to increased psychological activation in terms of self-reported stress. Because the participants were otherwise healthy and recruited from the general population, the results imply that subtle psychological stress processes may be important in the early development of environmental annoyance.

Modulation of sensory photophobia in essential blepharospasm with chromatic lenses

PURPOSE

To determine the effect of photochromatic modulation with tinted lenses on the sensory symptoms of photophobia in blepharospasm patients.

DESIGN

Nonrandomized case-control study.

PARTICIPANTS

Thirty-four subjects (24 benign essential blepharospasm patients and 10 normal controls).

METHODS

Subjects were seated in front of a calibrated light source. Beginning at 0%, the intensity of the light source was increased gradually until the patient reported symptomatic photophobia. The intensity of the light source was then measured with a light meter. This procedure was performed first with no chromatic lens and then with 7 different chromatic lenses, each blocking specific wavelengths of the visible spectrum. The subject was then asked which lens provided the greatest symptomatic improvement of photophobia. Statistical significance was calculated with analysis of variance and t test analysis.

MAIN OUTCOME MEASURES

Objective measurement of light intensity tolerated and subjective assessment of photophobia were obtained for each chromatic lens tested.

RESULTS

The light intensity tolerated by the normal subjects compared with the blepharospasm group was not statistically significant with no lens, but grew to 3.5 times that tolerated by the blepharospasm group as more of the higher wavelengths of the visible spectrum were blocked (P = 0.048). Lenses 4, 5, 6, and 7 allowed blepharospasm patients to tolerate a significantly higher intensity of light when compared with no lens (P = 0.04, P = 0.007, P = 0.03, and P = 0.01, respectively). Although the highest intensity of light tolerated was measured with lens 6, 71% of blepharospasm patients reported the greatest relief of photophobia with lens 7.

CONCLUSIONS

Blepharospasm patients tolerate a lower intensity of light when compared with normal subjects; this differential in light tolerance becomes significantly more pronounced as the higher wavelengths of the visible spectrum are blocked. The symptoms of photophobia in blepharospasm patients can be reduced significantly with photochromatic modulation. Despite lens 6 allowing the patients to tolerate a higher intensity of light, the majority of patients preferred lens 7 for symptomatic relief of photophobia. These findings suggest that sensory photophobia may be related more to the wavelength than to the intensity of the light exposure.

Fixation Stability and Macular Light Sensitivity in Patients with Diabetic Maculopathy: A Microperimetric Study with a Scanning Laser Ophthalmoscope

BACKGROUND

In patients with diabetic maculopathy, evaluation of visual acuity alone may not represent central retinal function sufficiently. Despite good visual acuity, patients may suffer from visual disturbances like waviness, relative scotoma, loss of fixation and decrease of contrast sensitivity. The aim of the study was to assess localized light sensitivity in the central visual field and to determine fixation stability in patients with diabetic maculopathy with moderate visual loss in comparison to healthy controls.

METHODS

Twenty-seven patients (mean age: 54 +/- 15; range 17-81 years) with diabetic maculopathy and 61 controls (mean age: 45 +/- 22; range 18-85 years) were included in the study. Light sensitivity was quantified by presenting stimuli with different light intensity with simultaneous real-time monitoring of the retina (intensity: 0-27.9 dB; size: Goldmann III, wavelength: 633 nm). Eye movements were controlled by semiautomatic fundus tracking. Fixation stability was quantified by measuring the area within 75% of all points of fixation.

RESULTS

Fixation stability was significantly decreased in diabetic patients in comparison to controls (43 +/- 22 vs. 31 +/- 16 arc min, p < 0.01). There was a significant difference in macular light sensitivity in diabetic patients compared to controls (19.6 +/- 0.5 dB), both in mean difference (15.6 +/- 1.4 dB) and if affected with macular edema (16.1 +/- 4.5 dB), hard exudates (13.3 +/- 6.7 dB), nonperfusion areas (10.3 +/- 7.9 dB) and laser burns (3.0 +/- 6.1 dB). Temporal parts of the macula were more affected than other parts. No correlation was found between visual acuity and foveal light sensitivity and foveal fixation, respectively.

CONCLUSION

Macular light sensitivity decreased progressively with the kind and severity of retinal alteration independent of visual acuity. The assessment of macular light sensitivity and stability of fixation with automatic threshold microperimetry may help to identify patients with diabetic maculopathy and could improve the management of diabetic maculopathy.

Importance of magnesium depletion with hypofunction of the biological clock in the pathophysiology of headhaches with photophobia, sudden infant death and some clinical forms of multiple sclerosis

Mg depletion is a type of Mg deficit due to a dysregulation of the Mg status. It cannot be corrected through nutritional supplementation only, but requires the most specific correction of the dysregulating mechanism. Among those, Biological Clock (BC) dysrhythmias are to be considered. The aim of this study is to analyze the clinical forms of Mg depletion with hypofunction of the Biological Clock (hBC). hBC may be due to either Primary disorders of BC [Suprachiasmatic Nuclei (SCN) and pineal gland (PG)] or Secondary with homeostatic response [reactive Photophobia (Pphi] to light neurostimulating effects [Nervous Hyper Excitability (NHE)]. The symptomatology is mainly diurnal and observed during fair weather (Spring,Summer). The elective marker of hBC is represented by a decrease in melatonin and in its metabolites in various fluids. The clinical forms of NHE due to Mg depletion with hBC are central and peripheral. The central forms associate anxiety, headaches and dyssomnia. The peripheral manifestations are neuromuscular: photosensitive epilepsia mainly. Three chronopathological forms of Mg depletion with hBC have been highlighted: 1. Headaches with Pphi: mainly migraine; 2. Sudden Infant Death Syndrome (SIDS); 3. Multiple Sclerosis (MS).- Headaches with Pphi, migraine particularly. These cephalalgias are diurnal with Pphi and are aggravated during the fair seasons (particularly during midnight sun-summer). Migraine is their typical form with its dishabituation to visual stimuli and its occipital cortex hyperexcitability. Comorbidity with anxiety is frequent. In 2/3 of the cases, it appears first.- SIDS might be linked to an impaired maturation of both photoendocrine system and brown adipose tissue. MS may be associated with primary disorders of BC Clinical forms of Mg depletion with hBC in MS present diurnal exacerbations and relapses during fair seasons. They have been underestimated because they disagree with the dogma of the << latitude gradient >>, presently questioned. Comorbidities with anxiety and migraine are frequent.hBC may be treated by using darkness therapy with a balanced Mg status. Absolute light deprivation should only be used only in acute indications and is time-limited. Partial substitutive therapy and chromatotherapy have not been validated yet and are still uncertain.

Spatial properties of photophobia

PURPOSE

To determine the spatial properties of stimuli that elicit photophobia (PP) in normal subjects: Does PP exhibit spatial summation? Are different parafoveal quadrants (superior, inferior, temporal, and nasal) of the retina differentially sensitive in PP? What is the relationship between PP sensitivity and retinal eccentricity? What is the relationship between the spatial properties of PP and the spatial distribution of macular pigment (MP)?

METHODS

A Maxwellian-view optical system with a xenon light source was used to present the stimuli. Four normal subjects viewed stimuli of various sizes, retinal locations, and one of two chromatic contents: xenon-white and a broadband orange. The intensity of the test stimulus was increased between trials until the PP threshold was reached. The squinting response corresponding to PP was assessed by electromyography and used as an objective criterion of PP. Three parameters were examined: stimulus size, parafoveal retinal locus (superior, inferior, temporal, and nasal), and retinal eccentricity (extending into the perifovea). Spatial profiles of MP were measured psychophysically using heterochromatic flicker photometry (HFP).

RESULTS

Spatial summation for PP was found essentially to adhere to Piper's law (radiance proportional to square root of stimulus area). The PP response was greater to centrally than peripherally viewed targets. In this regard, MP acted as a spatially integrated filter in the attenuation of PP.

CONCLUSIONS

The degree of spatial summation found for PP indicates that an increase of 1.0 log unit in field area results in an approximately 0.57-log-unit decrease in the radiance required to elicit PP. PP appears to serve the function of retinal photoprotection.

Pingelapese achromatopsia: correlation between paradoxical pupillary response and clinical features

AIM

To evaluate the paradoxical pupillary constriction in darkness in patients with Pingelapese achromatopsia (PA), and to describe a connection between this phenomenon and the clinical features.

METHODS

27 patients with PA were examined. All underwent a full ophthalmic examination which included Snellen visual acuity and ophthalmoscopy. Colour vision examination was performed with Ishihara pseudoisochromatic plates and also with a colour plate consisting of five basic colours (red, green, purple, yellow, and orange). Paradoxical pupillary response was examined and documented with a special infrared video camera. Pupils' images were analysed using the Scion Image program and the ratio of pupil size in darkness to its size in light was calculated and recorded.

RESULTS

Mean visual acuity was 20/400 (range 20/80-20/800). Colour vision examination showed a mean of 3.2 (SD 1.5) (range 1-5) of Ishihara colour plates, and 0.5 (0.75) (0-3) of basic colour plates. 23 patients (85%) had paradoxical pupillary constriction in darkness. Mean dark/light ratio of pupillary area was 0.86 (range 0.5-1.6). In patients with marked paradoxical pupillary constriction there was a significant correlation of visual acuity and Ishihara score.

CONCLUSIONS

Clinical manifestations of achromatopsia include total colour blindness, low visual acuity (mean of 20/400), horizontal pendular or rotatory nystagmus, and photophobia. Most patients have paradoxical pupillary constriction in darkness. When this response is brisk it seems to correlate with lower visual acuity and lower Ishihara score.

Cone dystrophy phenotype associated with a frameshift mutation (M280fsX291) in the alpha-subunit of cone specific transducin (GNAT2)

AIM

To describe the phenotype of a three generation consanguineous Pakistani family containing six individuals with autosomal recessive cone dystrophy caused by mutation in GNAT2.

METHODS

Five of the six affected individuals underwent an ophthalmological examination, electrodiagnostic testing, fundus photography, autofluorescence imaging, and detailed psychophysical testing.

RESULTS

All five examined patients had a history of nystagmus from infancy, photophobia, defective colour vision, and poor visual acuity. The nystagmus in three of the individuals had lessened with time. Fundus examination revealed an abnormal foveal appearance, without frank atrophy or pigmentation. Electroretinography (ERG) revealed absent ISCEV cone flicker ERGs with some preservation of responses to short wavelength stimulation. Rod ERGs showed no definite abnormality, but maximal (mixed rod-cone) response a-wave amplitudes were mildly subnormal. Rudimentary residual colour vision was detected in three individuals. There is clinical evidence of progressive visual acuity reduction in two older individuals.

CONCLUSION

Mutation in the alpha-subunit of cone specific transducin (GNAT2) is characterised by an infantile onset cone dystrophy. Some affected individuals may show deterioration of visual acuity with time.

Action spectrum for photophobia

Thresholds for photophobia (light-induced discomfort) were determined at wavelengths from 440 to 640 nm for three subjects. Photophobia was assessed by means of electromyography, which was used to measure subjects' level of squinting. After correction for absorption by macular pigment and the ocular media, subjects' functions displayed a trend of increasing sensitivity with decreasing wavelength. We propose that the corrected function is indicative of increased sensitivity to potential retinal damage by short-wavelength light. It is therefore suggested that photophobia serves a function of biological protection. Results also suggest that photophobia is significantly mitigated by macular pigment in the short wavelengths.

The predictive value of the penlight test for photophobia for serious eye pathology in general practice

BACKGROUND

Photophobia has been described as a useful sign in distinguishing severe from benign eye pathology.

OBJECTIVE

This observational study was performed to assess the utility of the penlight test for photophobia in patients presenting with a red eye in general practice.

METHODS

Thirty patients presenting with a red eye to one GP in 1 year were studied. All patients were examined with a penlight flashlight for photophobia. This was followed by slit-lamp examination for diagnosis of serious or benign eye pathology.

RESULTS

The penlight test was positive in eight out of 10 (80%) patients with serious pathology (mainly uveitis and keratitis) and was negative in 21 out of 26 (81%) patients with less serious pathology (mainly conjunctivitis). The positive predictive value of the test was 60% and the negative predictive value was 90% (chi-squared = 7, P = 0.001, odds ratio = 17, 95% confidence interval 2-179).

CONCLUSION

The penlight test for photophobia was found to be a useful test for distinguishing serious from benign eye pathology in a general practice population.

Increased intracranial blood flow volume in a preeclamptic woman with postpartum photophobia

BACKGROUND

Cerebral circulatory changes in preeclampsia are unclear. We studied the changes in intracranial blood flow volume using a new color Doppler ultrasonographic assessment in a preeclamptic woman with photophobia.

CASE

A 39-year-old preeclamptic primigravida was admitted and delivered by cesarean at 36 weeks' gestation. She developed bilateral photophobia with blood pressure elevation at 2 days postpartum. Blood flow volume index [mean velocity x pid(2)/4] (d = luminal diameter at systolic phase) was established. The sum of blood flow volume indexes of the bilateral internal carotid arteries and vertebral arteries increased at the onset of photophobia and blood pressure elevation. The blood flow volume index increased above 120 mm Hg of mean arterial blood pressure.

CONCLUSION

These data represent the increased cerebral hemodynamic changes in preeclampsia with photophobia.

Retinal light sensitivity in haemodialysis patients

PURPOSE

The aim of the present study was to compare retinal light sensitivity between normal healthy subjects and chronic renal failure patients treated with maintenance haemodialysis (HD), as well as to determine whether there is a correlation between visual field loss and the age of HD patients, duration of HD treatment and hypertensive retinopathy in HD patients.

METHODS

A total of 50 eyes of 25 HD patients (16 male, nine female) and 30 eyes of 15 controls underwent visual field testing on the C 30-2 program of the Humphrey field analyser.

RESULTS

Significant reduction in retinal light sensitivity with mean deviation (MD) P values less than 5% was found in 36% (18 eyes), pattern standard deviation (PSD) P values less than 5% in 16 eyes (32%) and corrected pattern standard deviation (CPSD) P values less than 5% in 16 eyes (32%) of HD patients. In control group, all MD, PSD, and CPSD P values were within normal limits. No correlation between reduction of retinal light sensitivity and age or duration of dialysis treatment was observed in HD patients. The reduction of retinal light sensitivity was significantly greater in HD patients with hypertensive retinopathy.

CONCLUSION

In 36% of eyes from our HD patients without ophthalmoscopically evident arteriolar occlusion on fundus examination, a significant reduction in retinal light sensitivity was observed. The reduction was significantly greater in HD patients with hypertensive retinopathy.

A clinical study of patients with hypersensitive teeth

Hypersensitive teeth have been a nemesis to patients in every dental practice. This clinical study was done to find a causal relationship of hypersensitive teeth and other organs of special senses, namely, sight, hearing, taste, smell, and touch. The analysis of the findings offers a basis for conclusion that dentition hypersensitivity and hypersensitivity of the special senses have a causal relationship. The dental clinician can provide the patient with an understanding and explanation of the cause(s) of hypersensitivity that will assist in a cooperative analysis of the symptoms and aid in the treatment to alleviate the pain.

Motion sickness and migraine: optokinetic stimulation increases scalp tenderness, pain sensitivity in the fingers and photophobia

The aim of this study was to determine whether scalp tenderness and photophobia, two well-recognized symptoms of migraine, develop during the motion sickness induced by optokinetic stimulation. To investigate whether motion sickness has a general influence on pain perception, pain was also assessed in the fingertips. After optokinetic stimulation, nausea increased more and headache persisted longer in 21 migraine sufferers than in 15 non-headache controls. Scalp tenderness increased during optokinetic stimulation in nauseated subjects, and pain in the fingertips increased more and photophobia persisted longer in migraine sufferers than controls. These findings suggest that the disturbance responsible for nausea also sensitizes trigeminal nociceptive neurones or releases inhibitory controls on their discharge. A low nausea threshold and a propensity for sensitization to develop rapidly in nociceptive pathways may increase susceptibility to migraine.

Abnormal activation in the visual cortex after corneal refractive surgery for myopia: demonstration by functional magnetic resonance imaging

OBJECTIVE

To try to correlate subjective photophobic symptoms with visual pathway modifications (from the retinal image to the visual cortex) after refractive surgery by exploring brain activation on photic stimulation.

DESIGN

Noncomparative case series.

PARTICIPANTS

Four subjects reporting discomfort produced by luminance (glare, halos, starbursts, or a combination thereof) in one eye after laser in situ keratomileusis (LASIK) were enrolled. The contralateral myopic eye (control) had no visual impairment and had undergone LASIK without complications or had not had previous surgery.

METHODS

Functional magnetic resonance imaging was performed during photic stimulation, delivered by an optical fiber, of the affected and unaffected eyes.

RESULTS

Functional magnetic resonance imaging provided evidence that most subjective visual symptoms correlated with anatomic flap abnormalities are associated with a higher signal increase in the visual association cortices compared with a nonsymptomatic eye.

CONCLUSIONS

Functional magnetic resonance imaging of the visual cortex may help in exploring the mechanisms involved in glare effects after refractive surgery.

Pain, photophobia, and retinal and optic nerve function after phacoemulsification with intracameral lidocaine

OBJECTIVE

To evaluate differences in pain, photophobia, retinal and optic nerve function in test eyes given intracameral lidocaine compared with control eyes given intracameral saline after phacoemulsification under topical anesthesia.

DESIGN

Prospective paired-eye intervention study with random treatment allocation.

PARTICIPANTS

Thirty eyes of 15 patients underwent cataract surgery in both eyes under topical anesthesia.

INTERVENTION

The first eye of each patient was randomly assigned to either 0.5 ml preservative-free 2% intracameral lidocaine or 0.5 ml of intracameral sterile saline. Within 5 months, the second eye automatically received intracameral saline if the first eye received intracameral lidocaine or vice versa.

MAIN OUTCOME MEASURES

The duration of surgery was recorded. Immediately after surgery, each patient was asked to evaluate the degree of pain and photophobia experienced during surgery using a nominal scale. In addition, in five patients, electroretinography (ERG) and visual evoked response (VER) were performed within 1 week before surgery, immediately after surgery, and 1 day after surgery. Amplitudes and latencies were calculated.

RESULTS

There was no difference in the duration of surgery comparing test eyes given intracameral lidocaine with control eyes given sterile saline (P = 0.81). There was no significant difference in the level of pain reported when comparing test eyes given intracameral lidocaine with control eyes (P = 1.00). None of the patients reported any significant difference in photophobia between their two eyes (P = 1.00). When comparing ERG measurements, test eyes given intracameral lidocaine did not show any significant decrease in ERG amplitudes or prolonged latencies compared with control eyes. When comparing VER measurements, test eyes given intracameral lidocaine did not show any increase in P1 latencies compared with control eyes (P = 0.31). When evaluating all postoperative ERG results 1 day after surgery, there was a suggestion of improved cone function.

CONCLUSIONS

Although intracameral lidocaine does not depress retinal or optic nerve function, the addition of intracameral lidocaine to topical anesthesia during phacoemulsification does not significantly reduce intraoperative pain or photophobia.

Influence of intense light stimulation on trigeminal and cervical pain perception thresholds

Thirty-three migraineurs and 23 healthy controls were submitted to pressure algometry before and after light-induced discomfort was elicited by progressive light stimulation in a monoblind fashion. Pressure algometries were performed on the emergence of the supraorbital, infraorbital, mental and greater occipital nerves, and over the temporal muscles, always throughout the same sequence and from right to left. Measurements were carried out before and immediately after light stimulation and after 10 min of the second algometry. The final result for each site measured at each time-point was the mean of the three measurements. Light stimulation was carried out progressively until light-induced discomfort was reported, to a maximum of 20,000 lux. A heat-blocking glass protected patients' eyes. Migraineurs presented significant and persistent drops in pain perception thresholds after light stimulation, at all sites tested (P = 0.002 to < 0.0001). These drops were not seen in controls, in whom, conversely, a less significant increase was seen on right infraorbital and left temporal muscle sites. Our results indicate that in migraineurs, light may have a relevant role in trigeminal and cervical pain perception thresholds.

Self-reported photophobic symptoms in migraineurs and controls are reliable and predict diagnostic category accurately

OBJECTIVES

To assess the reliability of self-reported photophobia across different patient populations and to examine how visual stress thresholds and photophobic symptoms may be predictive of diagnosis.

BACKGROUND

Relatively little is known about interictal photophobia in migraine. In particular, the variability of photophobia across different patient groups has not previously been studied, and a pathophysiological hypothesis to account for the symptoms is not agreed upon.

METHODS AND RESULTS

Study 1 compared 99 self-selected Dutch patients and 101 headache-free controls using survey methods. Patients both with and without aura were significantly more likely to report symptoms, such as the wearing of sunglasses in normal daylight, consistent with interictal photophobia. Study 2 replicated these findings in a series of consecutive referrals to a headache clinic in the United States. Study 3 used a specially designed laboratory test to examine the threshold for visual stress in those patients who had participated in study 2. Visual stress thresholds were significantly lower in patients than in controls. A discriminant function analysis of data from both studies 2 and 3 showed that diagnostic category (migraine; control) could be predicted from photophobic symptoms and visual stress thresholds at a level significantly better than chance.

CONCLUSIONS

We suggest that interictal photophobia is common in migraine and similar across different patient populations. One pathophysiological hypothesis is that interictal photophobia is associated with cortical hypersensitivity to stimulation. The predictive validity of interictal photophobic symptoms suggests that clinical diagnosis may be aided by questioning the patient about light sensitivity in the period between attacks.