Novel ATF6 homozygous variant in a Chinese patient with achromatopsia.

BACKGROUND: ATF6-associated Achromatopsia (ACHM) is a rare autosomal recessive disorder characterized by reduction of visual acuity, photophobia, nystagmus, and poor color vision. METHODS: Detailed ophthalmological examinations were performed in a Chinese patient with ACHM. Whole exome sequencing and Sanger sequencing were performed to detect the disease-causing gene in the patient. RESULTS: A 6-year-old girl presented photophobia, low vision and reduced color discrimination. Small yellow lesion in the macula of both eyes was observed. FAF demonstrated hypofluorescence in the macular fovea. OCT images revealed interruption of ellipsoid and interdigitation zone in the foveal area and a loss of the foveal pit. ERG showed relatively normal rod responses and unrecordable cone responses. Sequencing result identified a novel splicing variant c.354 + 6T>C in the ATF6 gene (NM_007348.4). CONCLUSIONS: We reported detailed clinical features and genetic analysis of a new Chinese ATF6-associated patient with ACHM.

Quantitative Assessment of Subjective Symptoms and Corneal Sensitivity in Chronic Orbital Pain Patients.

PURPOSE: To objectively evaluate the subjective symptoms and characteristics of chronic orbital pain as well as to quantify sensitization of peripheral trigeminal nerves. METHODS: In this prospective cohort study, patients who previously showed a response to peripheral trigeminal nerve blocks for unilateral, idiopathic chronic orbital pain and healthy subjects completed validated questionnaires assessing headaches, neuropathic signs and symptoms, photophobia, and pain qualities. Corneal sensitivity was measured in both eyes for all subjects with a Cochet-Bonnet aesthesiometer. For pain patients, the full assessment protocol was repeated 2-4 weeks after the study injection, and corneal sensitivity was also measured 30 minutes postinjection. Outcomes assessed were headache, neuropathic pain, and photophobia scores; pain qualities; and corneal sensitivity. RESULTS: Six female chronic orbital pain patients (mean age 48.2 years) and 11 female controls (mean age 47.5) were included. The mean headache, neuropathic pain, and photophobia questionnaire scores were significantly higher for pain patients than for controls (p < 0.001). On sensory testing, 5 pain patients (83.3%) endorsed allodynia, and all 6 (100%) had hyperalgesia in the ipsilateral frontal nerve dermatome. No controls had allodynia or hyperalgesia. Corneal sensitivity was similar between eyes in pain patients and between groups. Questionnaire scores and corneal sensitivity did not change significantly after the injection. CONCLUSIONS: Chronic orbital pain patients have a measurable reduction in quality of life due to headaches and photophobia. The supraorbital and supratrochlear nerves are sensitized, resulting in cutaneous hypersensitivity in the corresponding dermatome, but corneal nerves have normal sensitivity.

Comparison of pupil size in patients of migraine with photophobia versus normal subjects and correlation of the pupil size to severity of headache.

PURPOSE: To compare the pupil size of patients having migraine with photophobia versus normal subjects and to correlate the pupil size to the severity of headache. METHODS: This was a prospective case-control study. One hundred eyes of 50 patients who had migraine with photophobia were compared with same number of control subjects who had no history of headache. Pupil size was measured using the IOL Master 700 in all cases. Severity of headache was evaluated by the Migraine Disability Assessment (MIDAS) test questionnaire, and MIDAS grades from 1 to 4 ranging from minimal disability to severe disability were obtained in all cases. The pupil sizes in all grades were compared. RESULTS: The mean pupil size was 4.89 ± 0.9 mm (95% confidence interval [CI]) in patients of migraine with photophobia compared to 3.8 ± 0.49 mm (95% CI) in normal subjects, with a P value of <0.0001, which was statistically significant. Among the 50 patients with migraine, according to MIDAS grades, 20 had Grade 4 or severe disability, 15 had Grade 3 or moderate disability, 10 had Grade 2 or mild disability, and five had Grade 1 or minimal disability. Pupil size in Grade 4 category was the largest with a mean value of 5.6 ± 0.79 mm (95% CI). CONCLUSION: The pupil size in patients of migraine with photophobia is larger than in normal subjects and could be a trigger for the migraine attacks. The larger the pupil size, the more severe is the migraine disability.

Aniridic scleral fixation of intraocular lens: The answer to vision loss with photophobia!

Background: Aniridia is defined as missing iris tissue which can be partial, subtotal, or total. Characteristic clinical symptoms include photophobia and decreased visual acuity due to an increased light perception. In addition to this, disturbing cosmetic problems are prevalent. Even after implantation of an intraocular lens, patients often tend to be unsatisfied. Purpose: The answer to this problem lies in the implantation of an aniridic scleral fixation of intraocular lens (SFIOL), which has a central optical axis that acts as the refractive lens and a peripheral rim of a hyperpigmented area that mimics the iris and hence reduces photophobia. The purpose of the video was to demonstrate the use of black diaphragm intraocular lens (BDIOL) implantation, its surgical steps, and its outcomes. Synopsis: We report one such case where a young patient presented with post-traumatic aniridia with subluxated total cataract and spillover vitreous hemorrhage. He was subjected to a vitrectomy, cataract removal, and placement of an aniridic SFIOL with prolene 9-0 using the four-point fixation method. This gave an extremely gratifying outcome and solved both problems, that is, vision and photophobia. Highlight: Before implantation of the SFIOL, the patients had reduced visual acuity from aphakia and intolerable glare from aniridia. In this case-based approach and with relevant example, we tried to provide a solution for tricky scenarios like co-existing traumatic cataract and traumatic aniridia. The patient showed improved visual acuity and marked glare reduction after black diaphragm SFIOL implantation. Video link: https://youtu.be/atl60WetFsM.

Fotofobia intercrítica en el paciente migrañoso. Propuesta de criterios diagnósticos / Intercritical photophobia in the migraineous patient. Proposal for diagnostic criteria

Introducción: La fotofobia es un síntoma de intolerancia anómala a la luz sin sensación de dolor que requiere de una anamnesis y una exploración para el diagnóstico de una etiología subyacente.Procedimiento básico: El presente artículo se centra en 30 casos clínicos con fotofobia intensa aislada y su revisión de la bibliografía. Objetivo: El objetivo consiste en establecer unos criterios diagnósticos de la fotofobia. Resultados: La etiología de la fotofobia parece encontrarse a nivel de las células ganglionares de la retina intrínsecamente fotosensibles, conocidas como las células de la melanopsina, y a un nivel neuroquímico mediado por el péptido relacionado con la calcitonina y el péptido pituitario activador de la ciclasa. Conclusión: El tratamiento de la fotofobia podría consistir en anticuerpos monoclonales contra los péptidos relacionados con la calcitonina y/o el péptido pituitario activador de la ciclasa.(AU)

Introduction: Photophobia is a symptom of abnormal light intolerance without pain sensation that requires an anamnesis and an examination to diagnose an underlying etiology. Basic procedure: This article focuses on 30 clinical cases with isolated intense photophobia and on the review of the literature. Objective: The purpose of this article is to establish diagnostic criteria for photophobia. Results: The etiology of photophobia appears to be at the level of the intrinsically photosensitive retinal ganglion cells known as melanopsin cells and at a neurochemical level mediated by calcitonin-related peptide and the pituitary activating peptide cyclase. Conclusion: The treatment of photophobia could consist of monoclonal antibodies against calcitonin-related peptide and/or pituitary activating peptide cyclase.(AU)

Validation of the Utah Photophobia Symptom Impact Scale (version 2) as a headache-specific photophobia assessment tool.

OBJECTIVE: To present an updated version of the Utah Photophobia Symptom Impact Scale version 2 (UPSIS2), providing robust clinical and psychometric validation, to improve headache-specific evaluation of light sensitivity and headache-related photophobia. BACKGROUND: The original UPSIS filled a gap in available tools for assessment of headache-associated light sensitivity by providing patient-reported evaluation of the impact of light sensitivity on activities of daily living (ADLs). We have since revised the original questionnaire to provide a more robust item construct and refined validation approach. METHODS: We conducted a psychometric validation of the UPSIS2 through a primary analysis of an online survey of volunteers with recurrent headaches recruited from the University of Utah clinics and surrounding community. Volunteers completed the original UPSIS and UPSIS2 questionnaire versions in addition to measures of headache impact, disability, and frequency. The UPSIS2 now includes a pre-defined recall period and a 1-4 Likert scale with standardized response anchors to improve clarity. Internal construct validity, external construct validity, and test-retest reliability, were evaluated. RESULTS: Responses were obtained from 163 volunteers, with UPSIS2 scores ranging from 15 to 57 (out of a possible 15-60) with a mean (standard deviation) of 32.4 (8.80). Construct validity was satisfactory, as evidenced by sufficient unidimensionality, monotonicity, and local independence. Reliability was excellent, with Rasch test reliability = 0.90 and Cronbach's alpha = 0.92, and an intraclass correlation of 0.79 (95% confidence interval 0.65-0.88) for participants who took the test twice. UPSIS2 correlates well with other headache measures (Spearman's correlations >0.50), as well as the original UPSIS (Spearman's correlation = 0.87), indicating good convergent validity. UPSIS2 scores differ significantly across International Classification of Headache Disorders (third edition) groups, indicating good known group validity. CONCLUSION: The UPSIS2 provides a well-validated headache-specific outcome measure for the assessment of photophobia impact on ADLs.

[Expert consensus on the medical quality evaluation and improvement suggestions of in patients with chronic migraine].

Migraine is a highly disabling primary headache disease, accompanied by nausea, emesis, photophobia and phonophobia. Chronic migraine is usually developed from episodic migraine, and usually comorbids with anxiety, depression, and sleep disorders, further aggravating the disease burden. At present, the clinical diagnosis and treatment of migraine in China are not standard, and the migraine medical quality control evaluation system is lacking. In order to achieve standardized diagnosis and treatment of migraine, headache collaborators of Chinese Society of Neurology, based on national and international clinical research on diagnosis and treatment of migraine and combined with the current situation of China's medical system, drafted the expert consensus on the medical quality evaluation of inpatients with chronic migraine.

Clinical Neuroimaging of Photophobia in Individuals With Chronic Ocular Surface Pain.

PURPOSE: To examine neural mechanisms underlying photophobia in individuals with chronic ocular surface pain by using functional magnetic resonance imaging (fMRI). DESIGN: Cross-sectional case/control analysis. METHODS: A total of 16 individuals from the Miami Veterans Affairs eye clinic underwent comprehensive ocular surface evaluations and were surveyed for ocular surface symptoms. Case patients included patients who reported chronic ocular surface pain symptoms and light sensitivity at least most of the time over 1 week. Controls included persons without chronic ocular surface pain who reported no or minimal light sensitivity. All patients viewed light stimuli during 2 fMRI scans, one before and one after topical anesthetic instillation, and rated their level of pain intensity to the stimulus at the end of each scan. Areas of brain activation in response to light stimuli presentation were correlated with pain responses and examined post- vs pre-anesthesia. RESULTS: Case patients (n = 8) reported higher pain intensity ratings than controls (n = 8) in response to light stimuli during fMRI. Case patient ratings correlated more with light-evoked activation in pain-related areas within the trigeminal brainstem, primary somatosensory cortex (S1), anterior mid-cingulate cortex (aMCC), and insula than in controls. Topical anesthesia led to varying responses in pain ratings among case patients as well as decreased light-evoked activation in S1 and aMCC. CONCLUSIONS: The trigeminal nociceptive system may contribute to photophobia in individuals with chronic ocular surface pain. We demonstrate modulation of cortical structures in this pathway with topically applied anesthetic to the eyes. Further understanding of modulatory interactions that govern ocular surface pain and photophobia is critical for developing effective, precision-based therapies.

An intronic splice-site variant in MBTPS2 underlies ichthyosis follicularis with atrichia and photophobia syndrome.

Ichthyosis follicularis with atrichia and photophobia (IFAP) syndrome is a rare genodermatosis characterized by a classic triad of follicular ichthyosis, alopecia, and photophobia. We report a Chinese patient displaying features of IFAP triad along with painful palmoplantar keratoderma, recurrent infections, periorificial keratotic plaques, nail dystrophy, and pachyonychia. Whole-exome sequencing revealed an intronic variant (NM_015884.3: exon7:c.970+5G>A) in the gene MBTPS2. Sanger sequencing confirmed that the variant segerated with phenotype in the family. Sequencing of cDNAs derived from the patient indicated the variant introduced a new splice donor site, leading to partial skipping of exon 7 (r.951_970del). An in vitro mini-gene assay also revealed abnormal splicing of exon 7. This study presents a case complicated with X-linked IFAP syndrome and Olmsted syndrome, and highlights the significance of using validation assays to identify the pathogenicity of intronic variants in MBTPS2.

Expert consensus on the medical quality evaluation and improvement suggestions of in patients with chronic migraine / 中华内科杂志

Migraine is a highly disabling primary headache disease, accompanied by nausea, emesis, photophobia and phonophobia. Chronic migraine is usually developed from episodic migraine, and usually comorbids with anxiety, depression, and sleep disorders, further aggravating the disease burden. At present, the clinical diagnosis and treatment of migraine in China are not standard, and the migraine medical quality control evaluation system is lacking. In order to achieve standardized diagnosis and treatment of migraine, headache collaborators of Chinese Society of Neurology, based on national and international clinical research on diagnosis and treatment of migraine and combined with the current situation of China's medical system, drafted the expert consensus on the medical quality evaluation of inpatients with chronic migraine.

Photophobia as a Presenting Feature in Adie's Tonic Pupil.

A 34 years old female presented with complains of photophobia since 6-7 months. On examination, she had anisocoria of 4 mm in room light which increased in bright light. The left pupil was dilated and unresponsive to direct and indirect light stimuli. It did however, constrict slowly on near fixation followed by slow redilatation on distance fixation. A diagnosis of Adie's tonic pupil was made since left pupil constricted with instillation of dilute pilocarpine 0.1%. Her symptoms of photophobia and blurred vision immediately resolved. Photochromatic glasses and dilute pilocarpine 0.1% three times a day were prescribed. Prompt symptomatic relief of photophobia and blurred vision was observed.

Most bothersome symptoms in patients with migraine: A hospital-based study in Taiwan.

OBJECTIVE: To investigate the distribution, clinical associations, and treatment responses for the most bothersome symptoms of migraine in a large sample of patients with migraine in Taiwan. BACKGROUND: The most bothersome symptom is recently recommended as a co-primary endpoint in clinical trials of acute treatment of migraine. However, most clinical trials and observational studies have been conducted in the United States and Europe, with photophobia representing the most common most bothersome symptom. METHODS: Patients who were newly diagnosed with migraine by headache specialists in Taipei Veterans General Hospital were recruited. All participants completed a questionnaire for headache profile, including the most bothersome symptom. Clinical associations of the most bothersome symptoms and response rates to previous acute treatments were analyzed. RESULTS: Among the recruited 1188 patients with migraine (female 79.4%, mean age 39.0 ± 12.1 years) in this cross-sectional study, nausea (n = 729/1188, 61.4%) was the most common symptom that was most bothersome, followed by phonophobia (n = 280/1188, 23.6%), and photophobia (n = 122/1188, 10.3%). The frequency ranking was the same regardless of sex and age. Compared to migraine without aura, migraine with aura was associated with photophobia (adjusted odds ratio [OR] = 2.97, 95% confidence interval [CI] 1.76-5.0, p < 0.001). Chronic migraine was associated with phonophobia (adjusted OR = 1.51, 95% CI 1.13-2.01, p = 0.005), but there was a lower chance for nausea (adjusted OR = 0.68, 95% CI 0.53-0.88, p = 0.004), as the most bothersome symptom. Patients with different most-bothersome symptoms responded similarly to previous acute treatments, with an overall response rate of 52.2% (n = 550/1053). CONCLUSION: Patients with migraine in Taiwan reported a distinct ranking of the most bothersome symptom. However, the response rates of the most bothersome symptom and headache were similar, which supports the most bothersome symptom as an outcome measure for acute treatment of migraine. Further studies recruiting different populations are required to investigate regional differences in most bothersome symptoms.

The Unmet Challenge of Diagnosing and Treating Photophobia.

BACKGROUND: Although patients with abnormal light sensitivity may present to an ophthalmologist or optometrist for the evaluation of photophobia, there are no previous reviews of the most common causes of this symptom. METHODS: We conducted a retrospective chart review of patients who presented to our eye center between 2001 and 2009 primarily for the evaluation of photophobia. We recorded demographics, ocular examination findings, and diagnoses of these patients. RESULTS: Our population included 58 women and 53 men. The mean age at presentation to the clinic was 37 years (range 6 months-94 years). The most frequent cause of photophobia was migraine headache (53.7%), followed by dry eye syndrome (36.1), ocular trauma (8.2%), progressive supranuclear palsy (6.8%), and traumatic brain injury (4.1%). A significant proportion of patients (25.9%) left the clinic without a cause for their photophobia documented by the examining physician (11.7% of adults and 69.4% of children). CONCLUSIONS: Photophobia affects patients of all ages, and many patients are left without a specific diagnosis, indicating a significant knowledge gap among ophthalmologists and optometrists evaluating these patients.

Brain trauma impacts retinal processing: photoreceptor pathway interactions in traumatic light sensitivity.

BACKGROUND: Concussion-induced light sensitivity, or traumatic photalgia, is a lifelong debilitating problem for upwards of 50% of mild traumatic brain injury (mTBI) cases, though of unknown etiology. We employed spectral analysis of electroretinographic (ERG) responses to assess retinal changes in mTBI as a function of the degree of photalgia. METHODS: The design was a case-control study of the changes in the ERG waveform as a function of level of light sensitivity in individuals who had suffered incidents of mild traumatic brain injury. The mTBI participants were categorized into non-, mild-, and severe-photalgic groups based on their spectral nociophysical settings. Light-adapted ERG responses were recorded from each eye for 200 ms on-off stimulation of three spectral colors (R:red, G:green, and B:blue) and their sum (W:white) at the highest pain-free intensity level for each participant. The requirement of controls for testing hypersensitive individuals at lower light levels was addressed by recording a full light intensity series in the control group. RESULTS: Both the b-wave and the photopic negative response (PhNR) were significantly reduced in the non-photalgic mTBI group relative to controls. In the photalgic groups, the main b-wave peak shifted to the timing of the rod b-wave, with reduced amplitude at the timing of the cone response. CONCLUSION: These results suggest the interpretation that the primary etiology of the painful light sensitivity in mTBI is release of the rod pathway from cone-mediated inhibition at high light levels, causing overactivation of the rod pathway.

Development and validation of the Iris Glare, Appearance, and Photophobia questionnaire for patients with iris defects.

PURPOSE: To validate the Iris Glare, Appearance, and Photophobia (Iris GAP) questionnaire, a new symptom-based and appearance-based quality-of-life measure for patients with iris defects. SETTING: Single tertiary glaucoma clinic in Toronto, Ontario, Canada. DESIGN: Prospective cohort study. METHODS: Patients with varying degrees of iris defects were enrolled. Patients completed the Iris GAP questionnaire and the glare and driving subscales of the Refractive Status and Vision Profile (RSVP) questionnaire. Test-retest reliability, defined by Cronbach α and intraclass correlation coefficients (ICCs), was evaluated with repeat testing 2 weeks later. RESULTS: The study included 73 patients with iris defects, 68 controls with no iris defects, 77 patients with peripheral iridotomies (PIs) or transillumination defects (TIDs), and 22 patientswith surgically repaired irides (n = 22). Iris GAP scores ranged from 0 to 32 with a 97% completion rate. Iris GAP had high test-retest reliability (Cronbach α = 0.866, ICC = 0.953, P < .0005). Iris GAP scores were reliably distinguishable between patients with iris defects, repaired iris defects, and PIs and TIDs and controls (1-way analysis of variance, P < .0005). In pairwise comparisons, the major defect group had statistically significant higher scores than any of the other groups ( P < .005 for each). The control and repaired groups had the lowest scores, whereas the PI/TID group had intermediate scores. 9 patients underwent iris repair between tests and had a mean difference of 8.2 ± 6.2 points between their preoperative and postoperative scores ( P = .004). Iris GAP scores positively correlated with RSVP scores ( R2 = 0.73). CONCLUSIONS: Iris GAP can reliably evaluate symptomatology and patient-reported appearance in patients with iris defects.

Photophobia in headache disorders: characteristics and potential mechanisms.

Photophobia is present in multiple types of headache disorders. The coexistence of photophobia and headache suggested the potential reciprocal interactions between visual and pain pathways. In this review, we summarized the photophobic characteristics in different types of headache disorders in the context of the three diagnostic categories of headache disorders: (1) primary headaches: migraine, tension-type headache, and trigeminal autonomic cephalalgias; (2) secondary headaches: headaches attributed to traumatic brain injury, meningitis, non-traumatic subarachnoid hemorrhage and disorder of the eyes; (3) painful cranial neuropathies: trigeminal neuralgia and painful optic neuritis. We then discussed potential mechanisms for the coexistence of photophobia and headache. In conclusion, the characteristics of photophobia are different among these headache disorders. The coexistence of photophobia and headache is associated with the interactions between visual and pain pathway at retina, midbrain, thalamus, hypothalamus and visual cortex. The communication between these pathways may depend on calcitonin gene-related peptide and pituitary cyclase-activating polypeptide transmission. Moreover, cortical spreading depression, an upstream trigger of headache, also plays an important role in photophobia by increased nociceptive input to the thalamus.

Differential diagnosis and theories of pathophysiology of post-traumatic photophobia: A review.

BACKGROUND: Photophobia is a common sensory symptom after traumatic brain injury (TBI) that may have a grave impact on a patient's functional independence, neurorehabilitation, and activities of daily living. Post-TBI photophobia can be difficult to treat and the majority of patients can suffer chronically up to and beyond one year after their injury. OBJECTIVES: This review evaluates the current theories of the pathophysiology of photophobia and the most-common co-morbid etiologies of light sensitivity in TBI to help guide the differential diagnosis and individualized management of post-TBI photophobia. METHODS: Primary articles were found via PubMed and Google Scholar search of key terms including "photophobia" "light sensitivity" "photosensitivity" "photo-oculodynia" "intrinsically photosensitive retinal ganglion cells" "ipRGC" and "concussion" "brain injury" "dry eye". Due to paucity of literature papers were reviewed from 1900 to present in English. RESULTS: Recent advances in understanding the pathophysiology of photophobia in dry eye and migraine and their connection to intrinsically photosensitive retinal ganglion cells (ipRGC) have revealed complex and multifaceted trigeminovascular and trigeminoautonomic pathways underlying photophobia. Patients who suffer a TBI often have co-morbidities like dry eye and migraine that may influence the patient's photophobia. CONCLUSION: Post-traumatic photophobia is a complex multi-disciplinary complaint that can severely impact a patient's quality of life. Exploration of underlying etiology may allow for improved treatment and symptomatic relief for these patients beyond tinted lenses alone.

Infrared- and white-light retinal sensitivity in glaucomatous neuropathy.

Glaucoma causes irreversible neuropathy, which, untreated, may lead to blindness. In this case-control study, we measured two-photon infrared (IR) light sensitivity in glaucomatous eyes to propose a new method to quantify the visual loss. In total, 64 patients were recruited with an equal distribution between glaucoma and control groups. Retinal sensitivity to IR light was assessed using a two-photon excitation device. A fundus-driven microperimeter was used to measure retinal sensitivity to visible light. The retinal nerve fiber layer (RNFL) thickness was quantified automatically with optical coherence tomography. The IR sensitivity of glaucoma and control eyes differed significantly (P = .003): 9.8 (6.5 to 13.1) dB vs. 10.9 (8.2 to 13.0) dB. Although in the visible-light microperimetry, retinal sensitivity was decreased in glaucoma (17.0, range: 6.9 to 20.0 dB) compared to the controls (17.7, range: 11.6 to 20.0 dB), this difference did not reach the significance level. A significant thinning of the RNFL in the glaucoma group was observed (P < .001). IR sensitivity significantly correlated with the RNFL in three of the four assessed quadrants instead of only one in visible-light microperimetry. Although further research is needed, this proof-of-concept study suggests that IR-light sensitivity can be used to support the detection of glaucomatous neuropathy.

Visual photosensitivity threshold and objective photosensitivity luminance in healthy human eyes assessed using an automated ocular photosensitivity analyser: a step towards translation of a clinical tool for assessing photophobia.

PURPOSE: To evaluate the visual photosensitivity threshold and objective photosensitivity luminance in healthy eyes, thereby providing a normative dataset that will lead to a better understanding of diseases causing photophobia. METHODS: This was a prospective cross-sectional study. Emmetropes whose visual acuity was better than 0.18 logMAR (6/9) with no other ocular abnormality were included. Headache Impact Test-6 and visual light sensitivity questionnaires were administered. Visual photosensitivity threshold was measured subjectively using the ocular photosensitivity analyser. Objective photosensitivity luminance was assessed manually by evaluating videos recorded using an infrared camera and noting the intensity of light at the first squeezing reflex. RESULTS: Seventy five normal subjects (age range, 7-71 years) were included. Median age was 32.7 years (inter-quartile range, 20.3-47.9 years). Forty (53.3%) were males. Median Headache Impact Test score was 38 (inter-quartile range, 36-42) and visual light sensitivity questionnaire score was 11 (inter-quartile range, 8-15). Mean (standard deviation) right eye, left eye and binocular visual photosensitivity threshold was 3.34 (0.78), 3.33 (0.81) and 3.37 (0.78) loglux, respectively. There was a significant negative correlation of visual light sensitivity questionnaire scores with right eye, left eye and binocular visual photosensitivity thresholds, and positive correlation of age with binocular visual photosensitivity thresholds. Mean (standard deviation) right eye, left eye and binocular objective photosensitivity luminance was 3.25 (0.55), 3.35 (0.47) and 3.15 (0.52) loglux, respectively. Age was only positively correlated with binocular objective photosensitivity luminance, and there was no correlation between age and right eye or left eye objective photosensitivity luminance. CONCLUSIONS: The study characterised, for the first time, objective photosensitivity luminance and established normative data for both visual photosensitivity threshold and objective photosensitivity luminance. The data will help in understanding the pathophysiology of diseases causing photophobia, monitoring the disease progression and evaluating treatment modalities.

Photophobia and disability glare in adult patients with Marfan syndrome: a case-control study.

PURPOSE: The aim of the present study was to investigate photophobia and disability glare in adult patients with Marfan syndrome (MFS). METHODS: In this case-control study, 44 patients with MFS (87 eyes) were compared to 44 controls (88 eyes), who were matched for age and sex. The subjects were asked to grade their photophobia and glare using 10-cm visual analogue scales (VAS), which were marked with 'never' at zero and 'always' at 10 -cm. In addition, disability glare was measured with C-Quant straylight meter. RESULTS: The patients with MFS had significantly higher VAS scores than the controls in four out of seven statements related to photophobia and glare. When including cataract, spherical equivalent, iris colour, axial length and corneal curvature, three of the seven statements were still significantly different between the two groups. The mean straylight values were 1.29 ± 0.03 log(s) in the MFS group and 1.01 ± 0.03 log(s) in the control group (p < 0.001, mixed model). These differences remained significant after adjusting for cataract, spherical equivalent, iris colour, axial length and corneal curvature. CONCLUSION: Patients with MFS reported more photophobia and had a higher straylight value than the control group. Awareness of these findings of more photophobia and glare in the MFS patients is important when counselling and treating these patients.