Positive feedback loop between vision-related anxiety and self-reported visual difficulty.

BACKGROUND: Patients with Inherited Retinal Diseases typically experience progressive, irreversible vision loss resulting in low vision and blindness. As a result, these patients are at high risk for vision-related disability and psychological distress, including depression and anxiety. Historically, the relationship between self-reported visual difficulty (encompassing metrics of vision-related disability and quality of life, among others) and vision-related anxiety has been regarded as an association and not a causal relationship. As a result, there are limited interventions available that address vision-related anxiety and the psychological and behavioral components of self-reported visual difficulty. MATERIALS AND METHODS: We applied the Bradford Hill criteria to evaluate the case for a bidirectional causal relationship between vision-related anxiety and self-reported visual difficulty. RESULTS: There is sufficient evidence to satisfy all nine of the Bradford Hill criteria of causality (strength of association, consistency, biological gradient, temporality, experimental evidence, analogy, specificity, plausibility, and coherence) for the relationship between vision-related anxiety and self-reported visual difficulty. CONCLUSIONS: The evidence suggests that there is a direct positive feedback loop-a bidirectional causal relationship-between vision-related anxiety and self-reported visual difficulty. More longitudinal research on the relationship between objectively-measured vision impairment, self-reported visual difficulty, and vision-related psychological distress is needed. Additionally, more investigation of potential interventions for vision-related anxiety and visual difficulty is needed.

Effects of duration and number of symptoms on vision-related anxiety in patients with Inherited Retinal Diseases.

BACKGROUND: Patients with Inherited Retinal Diseases (IRDs) are at increased risk for vision-related anxiety due to progressive and irreversible vision loss, yet little is known about risk factors for anxiety in these patients. MATERIALS AND METHODS: This was a single-center, retrospective cross-sectional study at a large academic center. 128 adults with an IRD and without other significant eye conditions were recruited between December 2016 and March 2020. Participants were asked about the duration and number of symptoms they had in the following vision domains: reading, contrast vision, color vision, glare/light sensitivity, night vision, and peripheral vision. The outcomes of interest were the two domains of the Michigan Vision-Related Anxiety Questionnaire (MVAQ), rod- and cone-function related anxiety. We conducted an adjusted analysis to isolate the independent effect of duration and number of symptoms on vision-related anxiety. RESULTS: Of 126 participants had complete data, 62 (49%) were female and 64 (51%) were male, with an average age of 49 years (range: 18-87). Patients with duration of symptoms for greater than 25 years had an adjusted anxiety theta that was one-half standard deviations lower than patients with symptoms for less time. Patients with higher number of symptoms had higher anxiety theta after adjusting for confounding variables (p < 0.0001). CONCLUSIONS: The number of symptoms but not the duration of symptoms, is an independent risk factor for vision-related anxiety. Patients with more symptoms are at higher risk for vision-related anxiety. Having symptoms for longer than 25 years may reduce this anxiety.

Question: How does the duration and number of symptoms that patients with Inherited Retinal Diseases have affect their vision-related anxiety?Findings: In this cross-sectional study of 126 patients with Inherited Retinal Diseases, the number of symptoms, but not the duration of symptoms, was associated with higher vision-related anxiety. Patients with symptoms for longer than 25 years had less vision-related anxiety.Meaning: Patients with more vision-related symptoms may experience more vision-related anxiety.

Construct Validity of Inherited Retinal Disease-Specific Patient-Reported Outcome Measures.

PURPOSE: To evaluate aspects of construct validity of the Michigan Retinal Degeneration Questionnaire (MRDQ) and the Michigan Vision-related Anxiety Questionnaire (MVAQ). METHODS: Subjects with a clinical diagnosis of an inherited retinal disease (IRD) were recruited prospectively and 3 tests were used to assess construct validity: the ability to distinguish different IRD phenotypes; test a priori hypothesis of an association between vision-related anxiety and vision-related disabilities; and correlate MRDQ and MVAQ with the National Eye Institute Visual Functioning Questionnaire 25 (NEI VFQ-25) and the Impact of Vision Impairment (IVI). One-way analysis of variance (ANOVA) was used to compare different phenotypes for mean domain scores for MRDQ/MVAQ. Pearson correlations were performed between; Cone-Function Anxiety and Central Vision controlling for better eye visual acuity, Rod-Function Anxiety and Scotopic Function controlling for visual field area (III4e and IV4e), and scores of MRDQ/MVAQ, NEI VFQ-25, and IVI. RESULTS: The study sample consisted of 146 patients evenly divided between males and females, and mean age was 50 years. The 1-way ANOVA test was significant for distinguishing IRD phenotypes in 6 domains of MRDQ/MVAQ. Cone-Function Anxiety correlated with Central Vision controlling for visual acuity, Rod-Function Anxiety correlated with Scotopic Function controlling for visual field area, and all domains in MRDQ/MVAQ had significant correlations with NEI VFQ-25 and IVI composite scores. CONCLUSION: MRDQ and MVAQ domenstrate aspects of construct-validity set forth by the US Food and Drug Administration. The study futher supports the use of both patient-reported outcome measures in IRD clinical trials and natural history studies.NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Dramatic Improvement of Trichotillomania with 6 Months of Treatment With N-Acetylcysteine.

We present a case of a 17-year-old male with recurrent hair twirling resulting in patchy alopecia, who improved dramatically on N-acetylcysteine (NAC). Trichotillomania is characterized by repetitive hair pulling, twisting, or twirling and can vary from a mild habit to an impulse-control disorder. Standard treatment for pediatric trichotillomania includes cognitive behavioral therapy or medical therapy with selective serotonin reuptake inhibitors. NAC is a more recently utilized, safe, and well-tolerated over-the-counter supplement with some evidence of benefit for habitual skin and hair disorders. For this patient, we recommended 600 mg twice daily, increasing to 1200 mg twice daily as tolerated. After 6 months, our patient reported decreased desire to twirl his hair and his hair had almost completely regrown. Pediatricians who see patients with trichotillomania or other habitual disorders can consider treating these patients with NAC given its potential benefits and favorable side effect profile.

Phase 1b Randomized Controlled Study of Short Course Topical Recombinant Human Nerve Growth Factor (rhNGF) for Neuroenhancement in Glaucoma: Safety, Tolerability, and Efficacy Measure Outcomes.

PURPOSE: No approved therapies directly target retinal ganglion cells (RGCs) for neuroprotection or neuroenhancement in glaucoma. Recombinant human nerve growth factor (rhNGF) has been shown to promote RGC survival and function in animal models of optic neuropathy. Here we evaluate the safety, tolerability, and efficacy of short-term, high-dose rhNGF eye drops versus placebo in a cohort of glaucoma patients. DESIGN: This was a prospective, phase 1b, single-center, randomized, double-masked, vehicle-controlled, parallel-group study. METHODS: This study was designed to assess safety and tolerability as well as short-term neuroenhancement of structure and function (clinicaltrials.gov NCT02855450). A total of 60 open-angle glaucoma patients were randomized 40:20 to receive either 180 µg/mL rhNGF or vehicle control eye drops in both eyes, 3 times daily for 8 weeks, with a 24-week post-treatment follow-up. One eye was officially selected as the study eye, although both eyes were studied and dosed. Primary endpoints were safety, as assessed by adverse events, and tolerability, as assessed by patient-reported outcomes. Secondary outcome measures included best corrected visual acuity (BCVA), Humphrey visual field, electroretinograpy (ERG), and optical coherence tomography (OCT) of retinal nerve fiber layer (RNFL) thickness at baseline, after 8 weeks of treatment, and at 4 and 24 weeks after treatment (12 and 32 weeks total). RESULTS: Of the 60 randomized patients, 23 were female (38%) and the average age was 66.1 years. Through week 32, there were no treatment-related serious adverse events, including no unexpectedly severe progression of optic neuropathy, no adverse events affecting ocular function or pressure, and no drug-related systemic toxicity. Topical high-dose rhNGF was tolerated well, with a low level of symptom burden mainly eliciting periocular ache (in 52% of treated group and 5% of placebo group) and only 3 patients (7.5%) discontinuing treatment because of discomfort, of whom 1 patient (2.5%) prematurely withdrew from the study. There were no statistically significant differences in global indices of Humphrey visual field and no meaningful differences in total, quadrant, or clock-hour mean RNFL thickness between the groups, although both of these function and structure measures showed nonsignificant trends toward significance in favor of rhNGF. Real-world participant data was used to generate an estimate of cohort size needed to power subsequent studies. CONCLUSIONS: Use of rhNGF is safe and tolerable in a topical 180-µg/mL formulation. Although no statistically significant short-term neuroenhancement was detected in this trial, given the strong effects of NGF in preclinical models and the trends detected in this study, analysis for efficacy in a neuroprotection trial is warranted. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

The Michigan Retinal Degeneration Questionnaire: A Patient-Reported Outcome Instrument for Inherited Retinal Degenerations.

PURPOSE: To create a psychometrically validated patient-reported outcome measure for inherited retinal degenerations. DESIGN: Qualitative and quantitative patient-reported outcome (PROs) questionnaire development using item response theory validation. METHODS: One hundred twenty-eight patients with a diagnosis of an inherited retinal degeneration at the Kellogg Eye Center (University of Michigan) were recruited and administered a 166-item questionnaire comprising 7 expert-defined domains. The questionnaire was re-administered 4-16 days later to a subset of 25 participants to assess test-retest variability. Graded response models were fit by Cai's Metropolis-Hastings Robbins-Monro algorithm using the R (version 3.6.3) package mirt. Model data were fit to assess questionnaire dimensionality, to estimate item information, and to score participants. Poorly functioning items were removed, and the model was refit to create the final questionnaire. RESULTS: The psychometrically validated PROs measure was reduced to a 59-item questionnaire measuring 7 unidimesnional domains: central vision, color vision, contrast sensitivity, scotopic function, photopic peripheral vision, mesopic peripheral vision, and photosensitivity. A total of 39 items were removed because of poor factor loading, low item information, poor person-ability differentiation, or high item-level interdependence. This novel questionnaire produces a reliable domain score for person ability that does not show significant test-retest variability across repeated administration. CONCLUSIONS: The final PRO questionnaire, known as the Michigan Retinal Degeneration Questionnaire, is psychometrically validated and available for use in the evaluation of patients with inherited retinal degenerations.

The Michigan Vision-Related Anxiety Questionnaire: A Psychosocial Outcomes Measure for Inherited Retinal Degenerations.

OBJECTIVE: We sought to construct and validate a patient-reported outcome measure for screening and monitoring vision-related anxiety in patients with inherited retinal degenerations. DESIGN: Item-response theory and graded response modeling to quantitatively validate questionnaire items generated from qualitative interviews and patient feedback. METHODS: Patients at the Kellogg Eye Center (University of Michigan, Ann Arbor, Michigan, USA) with a clinical diagnosis of an inherited retinal degeneration (n = 128) participated in an interviewer-administered questionnaire. The questionnaire consisted of 166 items, 26 of which pertained to concepts of "worry" and "anxiety." The subset of vision-related anxiety questions was analyzed by a graded response model using the Cai Metropolis-Hastings Robbins-Monro algorithm in the R software mirt package. Item reduction was performed based on item fit, item information, and item discriminability. To assess test-retest variability, 25 participants completed the questionnaire a second time 4 to 16 days later. RESULTS: The final questionnaire consisted of 14 items divided into 2 unidimensional domains: rod function anxiety and cone function anxiety. The questionnaire exhibited convergent validity with the Patient Health Questionnaire for symptoms of depression and anxiety. This vision-related anxiety questionnaire has high marginal reliability (0.81 for rod-function anxiety, 0.83 for cone-function anxiety) and exhibits minimal test-retest variability (ρ = 0.81 [0.64-0.91] for rod-function anxiety and ρ = 0.83 [0.68-0.92] for cone-function anxiety). CONCLUSIONS: The Michigan Vision-Related Anxiety Questionnaire is a psychometrically validated 14-item patient-reported outcome measure to be used as a psychosocial screening and monitoring tool for patients with inherited retinal degenerations. It can be used in therapeutic clinical trials for measuring the benefit of an investigational therapy on a patient's vision-related anxiety.

Content generation for patient-reported outcome measures for retinal degeneration therapeutic trials.

PURPOSE: Generate content for a patient-reported outcome (PRO) measure for use in future clinical trials for inherited retinal degenerations. METHODS: Patients at the University of Michigan Kellogg Eye Center with a clinical diagnosis of inherited retinal degeneration with varying phenotypes were recruited for interviews. First, in-depth interviews were performed to solicit a wide range of patient experiences pertaining to visual function. Coders qualitatively analyzed the transcripts from these interviews using Atlas.ti software (Version 8.1.3 (522)) to draft questionnaire items. Next, the questionnaire was tested and refined based on participant feedback in cognitive interviews and administrator feedback in the pilot survey administration (pilot interviews). RESULTS: A total of 55 participants with a clinical diagnosis of inherited retinal degeneration were interviewed throughout the three study phases: in-depth interviews (n = 26), cognitive interviews (n = 16), and pilot interviews (n = 13). Coded items were analyzed for frequency of occurrence and related themes, then organized into common domains. Within each domain, PRO items were drafted to address the functional limitations or adaptations experienced by patients. CONCLUSIONS: Items for a PRO measure have been drafted and evaluated for interpretability in the target inherited retinal degeneration patient population. Content validity for the items was established through a process of in-depth interviews, cognitive interviews, and pilot interviews.

Occlusal pattern of cheek teeth in extant Spermophilus: A new approach to the identification of species.

Discrete characters of the occlusal surface (additional cusps) have been studied to elaborate a new approach to the identification of the Ground Squirrel species Spermophilus odessanus, S. suslicus, S. pygmaeus, S. citellus, and S. xanthoprymnus. Data on the presence/absence of the additional cusps have been represented as star plots and, in addition, have been studied using discriminant function analysis. The species-specific sets of the characters (patterns of bunodonty) have been revealed and are of high diagnostic value. The Citellus-set is defined by the presence of mesostyles and the rareness of the metastylids, paraconules and metaconules, hypostyles and protostyles. The Pygmaeus-set is characterized by the presence of additional cusps in the lower cheek teeth. The Odessanus-oriented set is found in the Spermophilus pygmaeus, S. odessanus, and S. suslicus. The relatively high frequency of additional cusps of the metaloph and the paraloph is characteristic for this set. The Plesiomorphic-set (characters shared by all the studied species and for this reason regarded herein as ancestral) is found in S. xanthoprymnus. The patterns of bunodonty serve as diagnostic criteria only as a whole: the shape of a star plot (relations among the character frequencies), rather than certain character values, is indicative. An optimal level of identification of species is possible based on the combination of the discrete characters mentioned and on the size parameters of the third upper molar. The occlusal sets are intended to remain stable during the time of species existence and seem to correspond to trends in specialization. The functional meaning of the sets can be explained by the dependence between the presence/absence of the discrete characters and the shape of the crown and its main lophs. Each pattern is likely to correspond to a trophic niche, and this niche corresponds to the species. J. Morphol. 277:814-825, 2016. © 2016 Wiley Periodicals, Inc.

Patterning the cone mosaic array in zebrafish retina requires specification of ultraviolet-sensitive cones.

Cone photoreceptors in teleost fish are organized in precise, crystalline arrays in the epithelial plane of the retina. In zebrafish, four distinct morphological/spectral cone types occupy specific, invariant positions within a regular lattice. The cone lattice is aligned orthogonal and parallel to circumference of the retinal hemisphere: it emerges as cones generated in a germinal zone at the retinal periphery are incorporated as single-cell columns into the cone lattice. Genetic disruption of the transcription factor Tbx2b eliminates most of the cone subtype maximally sensitive to ultraviolet (UV) wavelengths and also perturbs the long-range organization of the cone lattice. In the tbx2b mutant, the other three cone types (red, green, and blue cones) are specified in the correct proportion, differentiate normally, and acquire normal, planar polarized adhesive interactions mediated by Crumbs 2a and Crumbs 2b. Quantitative image analysis of cell adjacency revealed that the cones in the tbx2b mutant primarily have two nearest neighbors and align in single-cell-wide column fragments that are separated by rod photoreceptors. Some UV cones differentiate at the dorsal retinal margin in the tbx2b mutant, although they are severely dysmorphic and are eventually eliminated. Incorporating loss of UV cones during formation of cone columns at the margin into our previously published mathematical model of zebrafish cone mosaic formation (which uses bidirectional interactions between planar cell polarity proteins and anisotropic mechanical stresses in the plane of the retinal epithelium to generate regular columns of cones parallel to the margin) reproduces many features of the pattern disruptions seen in the tbx2b mutant.

Dexamethasone and oxytocin effects on rat Leydig cells--morphological and enzyme-histochemical characteristics.

In the present study the fine structure of rat Leydig cells was examined by electron microscopy. Oxytocin and dexamethasone induced changes in the activities of 3beta hydroxysteroid dehydrogenase, NADH2 cytochrome-C-reductase and glucose-6-phosphate dehydrogenase in these cells were studied in an in vivo experiment. Two groups of male Wistar rats were used to test the effects of oxytocin--rats from group I received a single injection of oxytocin; rats from group II were given a 10-day course of oxytocin. Pregnant female rats were injected with dexamethasone on day 17 and 18 post conception. The testes of 19 and 20-day old embryos were removed. It was established that both short and long term courses of oxytocin increased the activities of the above-mentioned enzymes. On the contrary, prenatal administration of dexamethasone decreased enzymatic activity in Leydig cells. Electron microscopy revealed clusters of fetal Leydig cells. Our results indicated the role of oxytocin in the local regulation of steroidogenesis and the importance of glucocorticoids in the differentiation and activity of Leydig cells.

Early Morphogenesis of Chick Gonad in the Absence of Mesonephros: (morphogenesis/gonad/mesonephric agenesis).

The development of the gonads in male and female chick embryos with induced unilateral mesonephric agenesis was studied using grafting, histoenzymology, and electron microscopy. As in embryos with a mesonephros, proliferation of the coelomic epithelium and its interaction with mesenchymal cells to form the medullary cords take place in the amesonephric gonads. In a similar manner, gonadal sexual differentiation and the differentiation of steroidogenic tissue, detectable by the presence of Δ5-3ß-hydroxysteroid dehydrogenase, do not appear to be affected by the absence of an organized mesonephros. However, the initiation of gonadal development, further growth, and the onset of meiosis observable in developing ovaries are retarded. This delay appears to be reversible, as was demonstrated by experiments in which ovaries from chicks with complete mesonephric agenesis were transplanted into the coelomic cavity of male and female 3 1/2-day-old embryos. Meiosis finally occurred in the oocytes of all ovaries, regardless of the sex of the host. Therefore, the presence of a differentiated mesonephros in chick embryos is not required for the establishment of an undifferentiated gonad and sexual differentiation, or for initiation of meiosis.