Case Report: Ocular Tilt Reaction with Internuclear Ophthalmoplegia and Multiple Cranial Nerve Palsies SIGNIFICANCE Ocular tilt reaction (OTR) is an abnormal eye-head postural reaction that consists of skew deviation, head tilt, and bilateral ocular torsion. Understanding of the pathway of the vestibulo-ocular reflex (VOR) is essential because this will help to localize the pathology. PURPOSE The aim of this study was to report a case of OTR with contralateral internuclear ophthalmoplegia (INO) and fifth and seventh cranial nerve palsies. CASE REPORT A 51-year-old gentleman with underlying diabetes mellitus presented with sudden onset of diplopia for 3 days. On examination, his visual acuity was 20/30 bilaterally without a relative afferent pupillary defect. He had a right OTR consisting of a right head tilt, a skew deviation with a left eye hypertropia, and bilateral ocular torsion (right excyclotorsion and left incyclotorsion) with nystagmus. He also had a left adduction deficit and right abduction nystagmus consistent with a left INO. Ocular examination revealed evidence of proliferative diabetic retinopathy bilaterally. Two days after the initial presentation, the patient developed left seventh and fifth cranial nerve palsies. MRI showed left pontine infarction and multiple chronic lacunar infarctions. There was an incidental finding of a vascular loop compression on cisternal portions of the left trigeminal, facial, and vestibulocochlear nerves. Antiplatelet treatment was started on top of a better diabetic control. The diplopia was gradually resolved with improved clinical signs. In this case, the left pontine infarction had likely affected the terminal decussated part of the vestibulocochlear nerve from the right VOR pathway, medial longitudinal fasciculus, and cranial nerve nuclei in the left pons. CONCLUSIONS The OTR can be ipsilateral to the lesion if the lesion is before the decussation of the VOR pathway in the pons, or it can be contralateral to the lesion if the lesion is after the decussation. In case of an OTR that is associated with contralateral INO and other contralateral cranial nerves palsy, a pathology in the pons that is contralateral to the OTR should be considered. Neuroimaging study can hence be targeted to identify the possible cause. |
Case Report: Effect of a Retinal Prosthesis System on Charles Bonnet Visual Hallucinations SIGNIFICANCE Charles Bonnet syndrome is commonly encountered and diagnosed in low-vision patients. It can be distressing for some of them, as there is no known effective treatment of this condition. Although there is a growing interest in retinal implants for blind patients with severe retinal diseases, the effect of these devices on Charles Bonnet syndrome visual hallucinations remains undocumented. PURPOSE The aim of this study was to report changes in the Charles Bonnet syndrome of a patient with retinitis pigmentosa after implantation of the Argus II retinal prosthesis. CASE REPORT A 65-year-old patient with retinitis pigmentosa and no light perception was frequently experiencing Charles Bonnet syndrome. In the hope of improving his vision, he received an Argus II retinal prosthesis in 2018 and participated in a 10-week rehabilitation program at the Institut Nazareth et Louis-Braille. The nature and the frequency of his Charles Bonnet syndrome were documented with the Questionnaire de repérage du syndrome de Charles Bonnet (a French questionnaire used to screen for Charles Bonnet syndrome) before the surgery and for 70 weeks after it. The patient's visual acuity and visual fields were monitored during the same period. Additional tests were administered to document the visual, psychological, and cognitive states of the patient throughout the study. CONCLUSIONS Although this case report confirmed that Argus II retinal prosthesis improves the performance of blind patients in visual tests, the improvement was not associated with a decrease in the symptoms of Charles Bonnet syndrome. |
Case Report: Use of Prosthetic Replacement of the Ocular Surface Ecosystem Treatment of Traumatic Lid Ptosis in a Pediatric Patient SIGNIFICANCE This report shares the long-term outcomes of an uncommon use of prosthetic replacement of the ocular surface ecosystem (PROSE) treatment and scleral lenses in the treatment for patients with ptosis who are not surgical candidates. PURPOSE This study aimed to describe a case of pediatric traumatic lid ptosis and follow-up during an 8-year period with PROSE treatment. CASE REPORT A 7-year-old Honduran girl presented with a history of severe cranial, facial, and ocular trauma as a result of a motor vehicle accident. Significant ptosis with left-sided facial paralysis and irregular astigmatism significantly reduced the patient's visual function in the left eye. She was evaluated and treated with a scleral prosthetic device in the left eye to improve vision, the ocular surface, and overall function for activities of daily living. After 8 years of PROSE treatment, acuity in the left eye remained stable at 20/25. The corneal health remained stable throughout this period, without complications of corneal neovascularization or corneal edema. CONCLUSIONS Prosthetic replacement of the ocular surface ecosystem treatment provided support of the ocular surface and mechanical left upper eyelid lift in a traumatic eyelid ptosis, ultimately providing improved visual function during an extensive 8-year period in a pediatric patient. Further studies are needed to evaluate the applicability of this approach in broader ptosis cases. |
Case Report: Effect of Haploscopic Filter on Contrast Sensitivity Function and Color Vision Tests SIGNIFICANCE The options that can help patients with congenital color vision defect, to a better professional and leisure adaptation, are very limited. Different haploscopic lenses can be considered, and their effects need to be investigated in patients with different defects. PURPOSE The purpose of this study was to present and discuss the effect of a pair of asymmetric long-pass filters fitted for deuteranopia, with the result of a 60% improvement in distinguishing red-green plates when compared with baseline. CASE REPORT We report the case of a 51-year-old man with congenital deuteranopia fitted with haploscopic ChromaGen filters. During the 2-month follow-up, we observed a decrease in left-eye logMAR visual acuity and contrast sensitivity with an increased ability to discriminate the plates of different color vision tests (Ishihara, Farnsworth, and Hardy-Rand-Rittler). The visual outcomes are discussed considering the spectral sensitivity curves of each filter, measured with a spectrophotometric device. CONCLUSIONS This report describes an improvement in the ability to resolve color vision plates after using asymmetric haploscopic filters showing a left-eye decrease in logMAR visual acuity and contrast sensitivity function. Subjects with a history of color vision deficiency might benefit from using haploscopic filters that selectively minimize the transmittance within a specific bandwidth to improve the color discrimination in deutan color vision deficiency. The simultaneous analysis of the color vision outcomes and transmittance spectrum of the haploscopic filters might contribute to a better understanding of the mechanisms behind the claimed efficacy of these devices. |
Case Report: Tropheryma whipplei Infection Presenting with Optic Disc Edema SIGNIFICANCE Whipple disease is a rare chronic, systemic bacterial infection that predominantly affects the small intestine but also other organs of the body. When left untreated, it can be not only vision threatening but also life threatening because of its central nervous system involvement. Therefore, early detection and treatment are important. PURPOSE We report a rare case of unilateral optic disc edema as a critical identifying sign of Whipple disease. CASE REPORT An asymptomatic 49-year-old African American man presented for an eye examination and was found to have optic nerve edema of the right eye. His best-corrected visual acuity was 20/20 in the right and left eye. He denied symptoms of diplopia, amaurosis fugax, or eye pain. His medical history was significant for HIV with no recent detectable viral load at the time of his eye examination. The patient denied any other infectious risk factors or changes in medical status. Extensive ophthalmic, neuroimaging, and laboratory investigations were completed as a comprehensive approach to rule out more common etiologies for unilateral optic disc edema. This initial workup yielded no identifying etiology, and the patient was monitored closely with frequent examinations with a retina specialist. Soon after his diagnosis of optic nerve edema, the patient developed new symptoms of chronic diarrhea, weight loss, and fatigue requiring hospitalization. Evaluations by internal medicine and gastroenterology, including serological testing, stool analysis, histological and microbiological analysis, esophagogastroduodenoscopy, and gastrointestinal biopsy, confirmed a diagnosis of Whipple disease that was successfully treated with oral antibiotics. CONCLUSIONS Whipple disease is a rare cause of infectious optic nerve edema that may present with other rheumatoid and gastrointestinal symptoms. A comprehensive medical approach for investigating unilateral optic nerve edema is paramount in diagnosing and treating Whipple disease. |
Technical Report: A New Method for Determining Image Distance for Stand Magnifiers SIGNIFICANCE Low vision rehabilitation clinicians must sometimes evaluate stand magnifiers to determine their true optical properties. A novel method is described for measuring the image distance of stand magnifiers. PURPOSE We describe a new method for determining the image distance of stand magnifiers, which has some advantages over previously described methods. METHODS Diverging light emerging from a stand magnifier is brought to a focus on the ceiling or other flat surface using convex lenses placed on the top of the stand magnifier lens. Knowing the power of this convex lens and the distance from the magnifier lens to the imaging surface, one can calculate the degree to which the emerging light is diverging and, from that, the image distance. Each author evaluated three stand magnifiers using this method and compared our results with each other and with the values for image distance published by the manufacturer. RESULTS Our method produced measurements that were consistent between three clinicians, with emerging divergence values differing by no more than 0.37 D and image distance differing by 0.6 to 3.1 cm for the three magnifiers evaluated. Our measured values also corresponded favorably with the published image distances listed in the manufacturer's catalog, deviating by a maximum of 3.7 cm and a mean of 1.3 cm. When the manufacturer's image distances were converted to dioptric divergence, our measurements varied by a maximum of 0.48 D and a mean of 0.17 D. CONCLUSIONS Our method provides an expedient and clinically accurate way to evaluate the divergence and image distance of a stand magnifier. Knowing the image distance is valuable by itself, but the divergence of the emerging light is also critical in determining the stand magnifier's enlargement ratio. |
Technical Report: The Mechanism of Contour Interaction Differs in the Fovea and Periphery SIGNIFICANCE Both foveal and peripheral contour interactions are based on, as yet, unexplained neural mechanisms. Our results show that, unlike foveal contour interaction, peripheral contour interaction cannot be explained on the basis of the antagonistic structure of neural receptive fields. PURPOSE Foveal contour interaction is markedly reduced for mesopic compared with photopic targets. This finding is consistent with an explanation based on the antagonistic structure of neural receptive fields. However, no reduction was found for low-luminance targets in the periphery, possibly because the luminances used previously remained substantially above peripheral scotopic detection thresholds. In this study, we compared foveal and peripheral contour interactions for long-wavelength photopic and mesopic targets, which would be expected to significantly elevate the peripheral retinal detection threshold. METHODS Five normal observers viewed a randomly selected Sloan letter surrounded by four flanking bars at several edge-to-edge separations (min arc). Photopic and mesopic stimuli were viewed foveally and at 6° peripherally through a selective red filter that ensured that mesopic targets were within 1 log unit of detection threshold at both retinal locations. RESULTS Whereas the magnitude of foveal contour interaction was substantially less at mesopic compared with photopic luminance (20 vs. 46% reduction of percent correct, on average), no significant difference was observed in peripheral contour interaction, which had average mesopic and photopic magnitudes of 38 and 40%. Moreover, confusion matrices representing photopic and mesopic contour interaction differed in the fovea but not in the periphery. The extent of contour interaction did not change with luminance at either retinal location. CONCLUSIONS Our results indicate that, although the characteristics of foveal contour interaction can be accounted for by the antagonistic structure of neural receptive fields, the same mechanism is not compatible with the characteristics of peripheral contour interaction. |
Convergence Insufficiency Neuro-mechanism in Adult Population Study Randomized Clinical Trial: Clinical Outcome Results SIGNIFICANCE These data confirm the effectiveness of office-based vergence/accommodative therapy for improving the near point of convergence and positive fusional vergence in young adults with symptomatic convergence insufficiency within a double-masked longitudinal randomized clinical trial. PURPOSE This study aimed to report changes in clinical signs and symptoms of convergence insufficiency from a randomized clinical trial evaluating the effectiveness of office-based vergence/accommodative therapy for young adults with symptomatic convergence insufficiency. METHODS In this double-masked, randomized clinical trial, convergence insufficiency patients (n = 50; average age, 21 ± 3 years; range, 18 to 32 years) were randomized to either office-based vergence/accommodative therapy or office-based placebo therapy. Improvements in (1) near point of convergence, (2) positive fusional vergence, and (3) self-reported symptoms (Convergence Insufficiency Symptom Survey [CISS] score) were evaluated after twelve 1-hour sessions of treatment within the office comparing the results from the vergence/accommodative therapy and the placebo therapy groups. RESULTS The mean near point of convergence improved by 6.0 and 3.1 cm in the vergence/accommodative and placebo therapy groups, respectively (mean difference of −2.9 cm; 95% confidence interval [CI], −4.6 to −1.0 cm; P < .01). The mean positive fusional vergence increased by 17.3 and 7.4Δ in the vergence/accommodative and placebo therapy groups, respectively (mean difference of 9.9Δ; 95% CI, 4.9 to 16.0Δ; P < .001). The mean CISS score improved by 12.4 and 10.1 points in the vergence/accommodative and placebo therapy groups, respectively (mean difference of 2.3 points; 95% CI, −8.3 to +4.6 points; P = .56). CONCLUSIONS Our results demonstrate that office-based vergence/accommodative therapy is effective for improving the near point of convergence and positive fusional vergence in young adults with symptomatic convergence insufficiency. However, given that both treatment groups had a similar reduction in self-reported symptoms, we recommend that the CISS be revised if it is to be used as an outcome measure in future studies of convergence insufficiency. |
How Do Different Digital Displays Affect the Ocular Surface? SIGNIFICANCE Digital display use has been accepted as a contributing factor to dry eye disease. Nowadays, plenty of new models of digital displays have been developed, and the differences in their nature and the ways in which they are set and used may contribute to differences in the eye-related problems they cause. PURPOSE This study aimed to analyze the differences in ocular surface, tear film, and visual fatigue parameters after reading on different digital displays, with and without initial instillation of artificial tears. METHODS Thirty-one healthy individuals ranging in age from 20 to 26 years (mean ± standard deviation, 21.26 ± 1.73 years) were included in this prospective clinical study. Subjects' ocular surface, tear film, and visual fatigue parameters were assessed after reading for 15 minutes on a laptop computer, tablet, e-reader, and smartphone with matching characteristics and a baseline measurement. Measurements were taken with and without the instillation of artificial tears before the reading tasks and included the Ocular Surface Disease Index questionnaire, the Computer Vision Syndrome Questionnaire, tear meniscus height, the Schirmer I test, noninvasive keratograph break-up time, osmolarity, bulbar redness, and pupil size. RESULTS Statistically significant differences in the Ocular Surface Disease Index, Computer Vision the Syndrome Questionnaire, tear meniscus height, the Schirmer I test, noninvasive keratograph break-up time, osmolarity, and bulbar redness were obtained when comparing the displays (P < .05). Best results were obtained with the smartphone and the e-reader. Conversely, the computer produced the highest disturbance on the ocular surface and tear film. Finally, the instillation of artificial tears revealed no statistical improvement of ocular surface or tear film parameters for the same device (P > .05). CONCLUSIONS Taking into account the clinical tests for dry eye diagnosis, the smartphone may be considered as the least disturbing display, producing lower dry eye signs and symptoms in comparison with other devices. |
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Medicine by Alexandros G. Sfakianakis,Anapafseos 5 Agios Nikolaos 72100 Crete Greece,00302841026182,00306932607174,alsfakia@gmail.com,
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