Toxic encephalopathy, vision loss, and memory disorder caused by acute acrylamide exposure.

Acrylamide (ACR) is an irritant that can cause damage to the eyes, skin, and nervous and reproductive systems. This study aims to illustrate a case of central nervous system and optic nerve damage from exposure to ACR. In this case, a 49-year-old male material handler was accidentally splashed with ACR solution on both of his upper limbs. Consequently, he was admitted to the hospital with toxic encephalopathy, characterized by cerebellar ataxia and slurred speech. Magnetic resonance imaging scan, a brain computed tomography scan blood sample analyses, optic coherence tomography, electroneuromyogram, and visual evoked potentials examination were performed. After 20 days of receiving symptomatic support treatment, the patient continued to experience disturbances in consciousness. Then, he developed vision loss, memory disorders, and symptoms of peripheral neuropathy such as skin peeling, extremity weakness, and absent tendon reflexes. This case report underscores the severe consequences of acute dermal exposure to high concentrations of ACR, resulting in toxic encephalopathy, visual impairment, and memory disorders, which will contribute to a broader understanding of ACR toxicity.

Reconsideration of Surgical Indication for Prolactin-producing Pituitary Tumor Focusing on Visual Impairment.

Prolactin-producing pituitary tumor (PRLoma) is the most prevalent functional pituitary tumor. If the tumor becomes large, vision can be impaired. In contrast to other pituitary tumors, cabergoline (CAB) is extremely effective for PRLoma and has become the first-line treatment. In this study, we examined our experience with the pharmacological and surgical management of PRLomas with visual impairment (VI) to determine whether VI could be a surgical indication. Further, we discussed the function of surgery in situations where the gold standard of PRLoma treatment was CAB administration. Of the 159 patients with PRLomas (age, 13-77 [mean = 36.3] years; men, 29; women, 130) at Tokyo Women's Medical University Hospital from 2009 to 2021, 18 (age, 15-67 [mean = 35.8] years; men, 12; woman, 6) had VI (subjectively, 12; objectively, 6). They started CAB treatment immediately (maximum dose: 0.5 to 6 mg/week; average: 2.17 mg/week). VI improved in 16 patients (88.9%) but did not improve in 2 (11.1%) requiring surgeries. One of the two patients had a parenchymal tumor resistant to CAB, and the other had a cystic tumor due to intratumoral bleeding. Consequently, CAB is the first-line treatment for PRLomas with VI because of its significantly high rate of improvement. However, close and rigorous surveillance is necessary for cases resistant to CAB, and the correct decision is required regarding surgical interventions at proper timing and appropriate surgical approaches considering the purpose of surgery.

Ethambutol and its ophthalmic effects; is screening and collaboration the new way forward?

AIM: To screen patients on ethambutol and evaluate its role on visual functions and toxic optic neuropathy. SETTING AND DESIGN: Retrospective, observational single tertiary centre cohort of 80 patients. METHODS AND MATERIAL: A total of 69 from the initial 80 patients with visual complaints were categorised into two groups A and B; ongoing anti-tubercular therapy with ethambutol and having stopped ethambutol for greater than six months respectively. All patients underwent vision (V) testing on ETDRS chart and anterior and posterior segment evaluation. Additionally, patients in group A recorded color vision (CV) on Ishihara chart and visual evoked potential (VEP). STATISTICAL ANALYSIS USED: P value was calculated using Chi square test (SPSS ver. 20). RESULTS: Out of 69 patients in our study, 58 (84.05%) patients recorded reduced visual acuity. The mean visual acuity was 0.58 logMAR units. 33 out of our 58 (57%) patients with reduced visual acuity showed normal optic discs while 25 out of 58 (43%) showed altered optic discs. In group B, 14 out of 32 patients with vision of less than 20/20 also had optic disc pallor (p = 0.02). 12 out of 15 patients in group A recorded an altered color vision and also had a vision of less than 20/20 (p = 0.023). 15 patients who recorded altered VEP also had vision of less than 20/20 (p = 0.037). CONCLUSION: Visual acuity, color vision and vep are sensitive and sustainable tools which can be implemented in regular screening. Ethambutol toxicity is a real problem and a collaborative approach is necessary to establish screening protocols and prevent ethambutol induced toxic optic neuropathy.

Long-Term Visual and Neurodevelopmental Outcomes in Two Children with Congenital Nystagmus Secondary to Methadone Exposure In utero.

Methadone is used as a substitute for illicit opioids during pregnancy. However, the real effect of this molecule on visual and neurodevelopmental outcomes of the children exposed is not fully understood, since studies considered subjects born to polydrug-dependent mothers and followed for few months/years. We report the long-term outcomes of two infants with congenital nystagmus solely exposed to methadone in utero. Neurological and neurovisual evaluations were performed every year from the first year of life to 11 years of age. One child was diagnosed with developmental coordination disorder. Both cases presented with ophthalmologic (refractive errors), oculomotor (nystagmus and fixation, smooth pursuit, and saccades dysfunctions), and perceptive problems (reduced visual acuity and contrast sensitivity). While nystagmus and other oculomotor dysfunctions remained stable over time, visual acuity and contrast sensitivity improved; refractive errors worsened and required corrective lenses. Both children showed normal neurodevelopmental and cognitive profile. This report highlights the long-term visual and developmental outcomes of two children exclusively exposed to methadone underlining the possibility of a visual dysfunction and motor coordination disorder. These observations prompt the need to investigate prenatal drug exposure as a cause of congenital nystagmus.

Anticholinergic syndrome: blurred vision and headache.

A young woman presented with blurred vision due to anticholinergic syndrome. We highlight the importance of considering this condition in the context of multiple medications and increased anticholinergic burden. The documented pupil abnormality gives an opportunity to review the syndrome of the reverse (inverse) Argyll Robertson pupil (preserved pupil light response with loss of accommodation). We review other situations in which the reverse Argyll Robertson pupil may occur and its possible mechanism in this case.

Closantel retinal toxicity: Recovery from severe vision loss after corticosteroid therapy.

PURPOSE: To present a relatively rare case of retinal toxicity and consequent severe vision loss due to Closantel ingestion. CASE REPORT: A 37-year-old female presented with sudden painless decrease vision in both eyes. She had no previous history of medical disease and denied any trauma. The patient had accidentally ingested Closantel a few days prior to presentation. Closantel is a veterinary anti-helminthic drug used mainly in livestock. Best corrected visual acuity (BCVA) at presentation was 20/200 bilaterally. There was no relative afferent pupillary defect (RAPD) and red saturation test was normal. Macular optical coherence tomography (OCT) revealed disruption in the outer retinal layer and ellipsoid zone in both eyes. A diagnosis of retinal toxicity due to Closantel was made and the patient was started on 1 mg/kg oral prednisolone acetate. On the 45th day after presentation, her BCVA had improved to 20/20 bilaterally. CONCLUSION: Closantel is a potentially toxic drug causing destruction of the neurosensory retina and visual disturbances. We suggest eye-care personnel awareness regarding the risk of Closantel-induced retinal toxicity and prompt treatment with systemic steroids should be considered.

Ocular toxicity following carboplatin chemotherapy for neuroendocrine tumour of the bladder.

INTRODUCTION: Carboplatin is a commonly used platinum analogue chemotherapeutic agent that is similar to cisplatin but is known to be better tolerated. This case report outlines a case of ocular toxicity following carboplatin chemotherapy used for the management of a neuroendocrine tumour of the bladder. CASE REPORT: A 70-year-old man with a history of neuroendocrine bladder cancer underwent chemotherapy with carboplatin and etoposide. He presented 4 weeks following his fourth chemotherapy cycle with a 1-week history of right eye blurriness. The patient had suffered a similar episode 2 weeks following his third chemotherapy cycle in his left eye. Carboplatin-induced ocular toxicity was suspected and his vision remained stable following cessation of carboplatin chemotherapy. DISCUSSION: Current literature on carboplatin-induced ocular toxicity remains scanty, however, previous cases have reported symptoms beginning 5 days to 2 weeks following carboplatin use. Visual disturbance in the form of altered colour vision, blind spot, blurred vision and metamorphopsia have been reported by previous literature. This case report emphasised a case of bilateral sequential blurring of vision following carboplatin chemotherapy. CONCLUSION: It remains critical for ophthalmologists and oncologists to look out for ocular side effects of chemotherapy due to its devastating effects.

RISK FACTORS OF VISION LOSS AND MULTIPLE RECURRENCES IN MYOPIC MACULAR NEOVASCULARIZATION.

PURPOSE: To investigate the factors associated with maximum visual improvement (peak vision) gain and the risk factors of peak vision loss and multiple recurrences in myopic macular neovascularization undergoing antivascular endothelial growth factor therapy. METHODS: Retrospective study of 310 eyes with active myopic macular neovascularization and median follow-up of 3.5 years. We defined peak vision gain as the maximum best-corrected visual acuity value reached under treatment and peak vision loss as best-corrected visual acuity never scoring as peak vision. We used multiple-event Prentice, Williams, and Peterson models to compute recurrences' incidence and Cox regression to identify risk factors for peak vision gain, peak vision loss, and multiple recurrences. RESULTS: Eyes with worse baseline best-corrected visual acuity {hazard ratio (HR) = 2.59 (95% confidence interval [CI]: 1.63-4.11) for 0.1 logMAR increase, P < 0.001} had higher chance to achieve peak vision. Peak vision was lost in 162 eyes (52%). Older age (HR = 1.22 [95% CI: 1.02-1.43] for 10-year increase, P = 0.02) and recurrences (HR = 1.10 [95% CI: 1.01-1.22] for event, P = 0.04) predicted nonsustained peak vision. Older age (HR = 1.13 [95% CI: 1.04-1.27] for 10-year increase, P = 0.006), larger myopic macular neovascularization (HR = 1.06 [95% CI: 1.01-1.13] for 1-mm 2 increase, P = 0.04), and juxtafoveal location (HR = 1.88 [95% CI: 1.28-2.77] vs. extrafoveal, P = 0.001) predicted multiple recurrences. CONCLUSION: Myopic macular neovascularization eyes lose vision mainly because of multiple recurrences. Patients at risk for recurrences should undergo more attentive monitoring to avoid vision loss.

Efectos neurológicos en trabajadores expuestos a tolueno. Revisión sistemática / Neurological effects in workers exposed to toluene. Systematic review

Introducción y objetivo: el tolueno es un disolvente orgánico derivado del benceno empleado en diversas indus-trias, con potenciales efectos nocivos para los trabajadores. Este estudio pretende conocer los posibles efectos neurológicos que presentan los trabajadores expuestos a tolueno.Material y métodos: revisión sistemática de estudios publicados en inglés y español entre enero/2000-diciem-bre/2021. Las bases de datos consultadas fueron MEDLINE, WOS, Scopus, Embase, LILACS, IBECS y Cochrane Li-brary. La calidad de los estudios se evaluó mediante la declaración STROBE y el nivel de evidencia mediante los criterios SIGN.Resultados: Se incluyeron 14 estudios observacionales (calidad entre 13-18, nivel de evidencia entre 2+ y 3). Ocho estudios examinaron síntomas neurológicos inespecíficos y alteraciones del comportamiento encontrando un au-mento de síntomas como cefalea, náuseas o vómitos, y una disminución del rendimiento motor y atención en tra-bajadores expuestos a tolueno (p<0,05). Cuatro estudios examinaron los efectos visuales, encontrando valores de Índice de Confusión de Color (CCI) más elevados en el grupo expuesto (p<0,05). Por último, dos estudios examina-ron los efectos del tolueno sobre la audición en co-exposición con ruido, observando en uno de ellos agravamiento de la pérdida auditiva en ambiente ruidoso (concentración media 33-164,6ppm), (p<0,001); mientras que en el otro estudio no se observaron efectos a concentraciones ≤50ppm.Conclusión: la exposición laboral a tolueno produce efectos neurológicos como síntomas inespecíficos, alteracio-nes del comportamiento, y efectos en la visión y en la audición. No obstante, es necesario realizar estudios con mejor diseño y calidad metodológica, ajustando factores de confusión y con mayor tamaño muestral (AU)

Introduction and objective: toluene is an organic solvent derived from benzene used in various industries, with potential harmful effects for workers. This study aims to determine the possible neurological effects of workers exposed to toluene.Material and methods: Systematic review of studies published in English and Spanish between January/2000-De-cember/2021. The databases consulted were MEDLINE, WOS, Scopus, Embase, LILACS, IBECS and Cochrane Library. Study quality was assessed using the STROBE statement and the level of evidence using the SIGN criteria.Results: 14 observational studies were included (quality between 13-18, level of evidence between 2+ and 3). Eight studies examined non-specific neurological symptoms and behavioral alterations, finding an increase in symptoms such as headache, nausea or vomiting, and a decrease in motor performance and attention in workers exposed to toluene (p<0.05). Four studies examined visual effects, finding higher Color Confusion Index (CCI) values in the exposed group (p<0.05). Finally, two studies examined the effects of toluene on hearing in co-exposure with noise observing in one of them aggravation of hearing loss in noisy environment (mean concentration 33-164.6ppm), (p<0.001); while in the other study no effects were observed at concentrations ≤50ppm.Conclusion: occupational exposure to toluene produces neurological effects such as nonspecific symptoms, behav-ioral alterations, and effects on vision and hearing. However, it is necessary to carry out studies with better design and methodological quality, adjusting for confounding factors and with a larger sample size (AU)

Probable Methylphenidate-Related Reversible "Visual Snow" in a Child With ADHD.

OBJECTIVES: Visual snow syndrome is relatively a recently recognized neurological entity presenting primarily with positive visual disturbance. Etiology is largely speculative. METHODS: Authors report here on a child case of ADHD that developed a probable visual snow syndrome related to methylphenidate. RESULTS AND CONCLUSIONS: Although remaining rare, prescribers ought to be cognizant of such unusual methylphenidate-related perceptual alterations.

MERCI: a machine learning approach to identifying hydroxychloroquine retinopathy using mfERG.

PURPOSE: Hydroxychloroquine (HCQ) is an anti-inflammatory drug in widespread use for the treatment of systemic auto-immune diseases. Vision loss caused by retinal toxicity is a significant risk associated with long term HCQ therapy. Identifying patients at risk of developing retinal toxicity can help prevent vision loss and improve the quality of life for patients. This paper presents updated reference thresholds and examines the diagnostic accuracy of a machine learning approach for identifying retinal toxicity using the multifocal Electroretinogram (mfERG). METHODS: A retrospective study of patients referred for mfERG testing to detect HCQ retinopathy. A consecutive series of all patients referred to Kensington Vision and Research Centre between August 2017 and July 2020 were considered eligible. Eyes suspect for other ocular pathology including widespread retinal disease and advanced macular pathology unrelated to HCQ or with poor quality mfERG recordings were excluded. All patients received mfERG testing and Ocular Coherence Tomography (OCT) imaging. Presence of HCQ retinopathy was based on ring ratio analysis using clinical reference thresholds established at KVRC coupled with structural features observed on OCT, the clinical reference standard. A Support Vector Machine (SVM) using selected features of the mfERG was trained. Accuracy, sensitivity and specificity are reported. RESULTS: 1463 eyes of 748 patients were included in the study. SVM model performance was assessed on 293 eyes from 265 patients. 55 eyes from 54 patients were identified as demonstrating HCQ retinopathy based on the clinical reference standard, 50 eyes from 49 patients were identified by the SVM. Our SVM achieves an accuracy of 85.3% with a sensitivity of 90.9% and specificity of 84.0%. CONCLUSIONS: Machine learning approaches can be applied to mfERG analysis to identify patients at risk of retinopathy caused by HCQ therapy.

Severe visual loss caused by inhalational methanol poisoning in fireworks production: A report on 3 cases.

BACKGROUND: Workers in fireworks production are mainly at risk for explosion injury. However, there are few reports on the consequences of methanol poisoning in fireworks laborers. CASE PRESENTATION: We report on three patients with visual loss caused by inhalation exposure to high concentrations of methanol, who were engaged in the granulation process of the fireworks manufacturing industry. They presented with severe metabolic acidosis and visual impairments, accompanied by headache, chest tightness, shortness of breath, dizziness, and vomiting. All were diagnosed with acute methanol poisoning. One patient developed bilateral blindness and two patients improved after timely hemodialysis treatment. CONCLUSIONS: These case reports emphasize the risk of methanol poisoning in the fireworks industry or other factories using commercial alcohol with high methanol content. Early hemodialysis intervention and metabolic acidosis correction are crucial for rescuing visual impairment caused by methanol exposure. Awareness and supervision of commercial alcohol use are indispensable for similar industrial processes.

Corneal Allograft Rejection Associated With Herpes Zoster Recombinant Adjuvanted Vaccine.

PURPOSE: The purpose of this article is to report 3 cases of corneal allograft rejection that occurred in temporal proximity to administration of the zoster subunit vaccine (RZV). METHODS: Three cases of corneal transplant rejection that developed after RZV administration were identified. Clinical history, including existence of other risk factors, timing of rejection, corticosteroid therapy at the time of onset of rejection, and course were reviewed. RESULTS: The onset of symptoms occurred 5 weeks after the first RZV dose in 1 patient and 1 and 6 weeks after the second dose in the other 2 patients. Coexisting risk factors included history of endothelial keratoplasty in the fellow eye in 1 patient and previous failure of a penetrating keratoplasty because of rejection in a second patient. The third patient had a history of 1 episode of rejection in a previous graft that resolved and then experienced graft failure over several years. In 2 patients, rejection developed despite relatively high levels of topical steroid therapy: prednisolone acetate 1%, 4 × per day in 1 patient and difluprednate 0.05%, 3 × per day in a second patient. CONCLUSIONS: RZV, which elicits a more robust immune reaction than the zoster live-attenuated vaccine, ZVL, may increase the risk of allograft rejection in immunocompetent patients with preexisting corneal endothelial or penetrating transplants. Based on the available data, it may be reasonable to increase the topical corticosteroid regimen before the first dose, until approximately 3 months after the second dose of ZVL.

Visual impairment and medication safety: a protocol for a scoping review.

BACKGROUND: The number of individuals with a visual impairment in the UK was estimated a few years ago to be around 1.8 million. People can be visually impaired from birth, childhood, early adulthood or later in life. Those with visual impairment are subject to health inequities and increased risk for patient safety incidents in comparison to the general population. They are also known to be at an increased risk of experiencing medication errors compared to those without visual impairment. In view of this, this review aims to understand the issues of medication safety for VI people. METHODS/DESIGN: Four electronic bibliographic databases will be searched: MEDLINE, Embase, PsycInfo and CINAHL. Our search strategy will include search combinations of two key blocks of terms. Studies will not be excluded based on design. Included studies will be empirical studies. They will include studies that relate to both medication safety and visual impairment. Two reviewers (SG and LR) will screen all the titles and abstracts. SG, LR, RM, SCS and PL will perform study selection and data extraction using standard forms. Disagreements will be resolved through discussion or third party adjudication. Data to be collected will include study characteristics (year, objective, research method, setting, country), participant characteristics (number, age, gender, diagnoses), medication safety incident type and characteristics. DISCUSSION: The review will summarise the literature relating to medication safety and visual impairment.

Central neurotoxicity induced by trastuzumab emtansine (T-DM1): a case report.

Trastuzumab emtansine (T-DM1) is a human epidermal growth factor receptor 2 (Her2) - targeted antibody-drug conjugate that is approved for patients previously treated with trastuzumab and a taxane for Her2-positive advanced breast cancer and those who have progressed within 6 months of completion of adjuvant chemotherapy, as well as for patients with residual invasive Her2-positive disease after the completion of adjuvant chemotherapy. Peripheral neuropathy is a common adverse event; however, ocular events have also been described. With the current report we present the case of a 67-year old woman who developed transient grade 2-3 blurred vision after the first T-DM1 infusion, which was complicated with grade 2 diplopia causing vertigo after the second infusion. After extended investigation, this symptomatology was attributed to central neurotoxicity, and gradually resolved after T-DM1 discontinuation.

Visual Disfunction due to the Selective Effect of Glutamate Agonists on Retinal Cells.

One of the causes of nervous system degeneration is an excess of glutamate released upon several diseases. Glutamate analogs, like N-methyl-DL-aspartate (NMDA) and kainic acid (KA), have been shown to induce experimental retinal neurotoxicity. Previous results have shown that NMDA/KA neurotoxicity induces significant changes in the full field electroretinogram response, a thinning on the inner retinal layers, and retinal ganglion cell death. However, not all types of retinal neurons experience the same degree of injury in response to the excitotoxic stimulus. The goal of the present work is to address the effect of intraocular injection of different doses of NMDA/KA on the structure and function of several types of retinal cells and their functionality. To globally analyze the effect of glutamate receptor activation in the retina after the intraocular injection of excitotoxic agents, a combination of histological, electrophysiological, and functional tools has been employed to assess the changes in the retinal structure and function. Retinal excitotoxicity caused by the intraocular injection of a mixture of NMDA/KA causes a harmful effect characterized by a great loss of bipolar, amacrine, and retinal ganglion cells, as well as the degeneration of the inner retina. This process leads to a loss of retinal cell functionality characterized by an impairment of light sensitivity and visual acuity, with a strong effect on the retinal OFF pathway. The structural and functional injury suffered by the retina suggests the importance of the glutamate receptors expressed by different types of retinal cells. The effect of glutamate agonists on the OFF pathway represents one of the main findings of the study, as the evaluation of the retinal lesions caused by excitotoxicity could be specifically explored using tests that evaluate the OFF pathway.

Severe visual loss by inhalation of methanol.

Purpose: To describe a clinical case of toxic optic neuropathy with severe visual loss caused by inhalation abuse of methanol products. Method: A 25-year-old male student was admitted to the emergency department with an acute bilateral visual loss and headaches, nausea, and cold sweats. A complete clinical and ophthalmologic examination was performed. Results: On ophthalmic examination, visual acuity (VA) was light perception in the right eye (RE) and no light perception in the left eye (LE). Pupillary examinations demonstrated dilated, non-reactive pupils. An arterial blood gas analysis showed systemic metabolic acidosis with a pH of 7.23 and Gap anion elevated. Consequently, these results were enough to provide a substantial suspicion of methanol toxicity and start the treatment. 72 hours after, he confessed that he had been inhaling methanol-based solvent for eight years. Conclusions: Methanol-induced toxicity can cause a non-reversible toxic optic neuropathy. Blood acidemia with Gap anion elevated and a suspicious fundus ophthalmic examination allows a fast diagnosis. A quick treatment based on dialysis, intravenous ethanol, sodium bicarbonate, vitamin B12, and intravenous methylprednisolone slows the secondary intoxication damages. We presented herein a procedure to identify and manage toxic optic neuropathy caused by methanol inhalation. Abbreviations: VA = Visual Acuity, RE = right eye, LE = left eye, OCT = Optical Coherence Tomography, RNFL = Retinal Nerve Fiber Layer, CT = computed tomography, MRI = magnetic resonance imaging, VEPs = visual evoked potentials.