Bilateral Loss Research Articles

Navigation strategies in patients with vestibular loss tested in a virtual reality T-maze.

During navigation, humans mainly rely on egocentric and allocentric spatial strategies, two different frames of reference working together to build a coherent representation of the environment. Spatial memory deficits during navigation have been repeatedly reported in patients with vestibular disorders. However, little is known about how vestibular disorders can change the use of spatial navigation strategies. Here, we used a new reverse T-maze paradigm in virtual reality to explore whether vestibular loss specifically modifies the use of egocentric or allocentric spatial strategies in patients with unilateral (n = 23) and bilateral (n = 23) vestibular loss compared to healthy volunteers (n = 23)matched for age, sex and education level. Results showed that the odds of selecting and using a specific strategy in the T-maze were significantly reduced in both unilateral and bilateral vestibular loss. An exploratory analysis suggests that only right vestibular loss decreased the odds of adopting a spatial strategy, indicating an asymmetry of vestibular functions. When considering patients who used strategies to navigate, we observed that a bilateral vestibular loss reduced the odds to use an allocentric strategy, whereas a unilateral vestibular loss decreased the odds to use an egocentric strategy. Age was significantly associated with an overall lower chance to adopt a navigation strategy and, more specifically, with a decrease in the odds of using an allocentric strategy. We did not observe any sex difference in the ability to select and use a specific navigation strategy. Findings are discussed in light of previous studies on visuo-spatial abilities and studies of vestibulo-hippocampal interactions in peripheral vestibular disorders. We discuss the potential impact of the history of the disease (chronic stage in patients with a bilateral vestibulopathy vs. subacute stage in patients with a unilateral vestibular loss), of hearing impairment and non-specific attentional deficits in patients with vestibular disorders.

Dominant Optic Atrophy Caused by the c.1334G>A Mutation of the OPA1 Gene

Purpose: Dominant optic atrophy is one of the most common hereditary optic neuropathies, causing progressive bilateral vision loss that begins early in life. Optic atrophy 1 (OPA1) gene mutation brings about mitochondrial dysfunction, which results in clinical manifestations of dominant optic atrophy. Here, we report a case of dominant optic atrophy caused by the c.1334G>A mutation of the OPA1 gene, the first known case in Korea to our knowledge.Case summary: A 12-year-old female patient with no specific medical history or systemic symptoms visited our clinic complaining of a progressive decrease in vision in either eye. Slit-lamp microscopy, intraocular pressure, ocular motility, and pupil reflex were normal. However, her best-corrected visual acuity in both eyes was 20/100, and her color vision was reduced to 8/12 in Ishihara’s test. Fundus examination showed temporal pallor of the optic nerve head in both eyes, and a corresponding cecocentral scotoma was observed on Goldmann visual field examination. Optical coherence tomography revealed significant thinning of the peripapillary retinal fiber layer and macular ganglion cell layer in both eyes. Genetic examination confirmed the c.1334G>A mutation of the OPA1 gene.Conclusions: We report a case of dominant optic nerve atrophy caused by c.1334G>A mutation of the OPA1 gene and its clinical manifestations.

Leber Hereditary Optic Neuropathy Gene Therapy: Adverse Events and Visual Acuity Results of All Patient Groups

To assess safety of gene therapy in G11778A Leber hereditary optic neuropathy (LHON). Phase 1 clinical trial. Setting: single institution. Patients with G11778A LHON and chronic bilateral visual loss >12 months (group 1, n=11), acute bilateral visual loss <12 months (group 2, n=9), or unilateral visual loss (group 3, n=8). unilateral intravitreal AAV2(Y444,500,730F)-P1ND4v2 injection with low, medium, high, and higher doses to worse eye for groups 1 and 2 and better eye for group 3. Best-corrected visual acuity (BCVA), adverse events, and vector antibody responses. Mean follow-up was 24 months (range, 12-36 months); BCVAs were compared with a published prospective natural history cohort with designated surrogate study and fellow eyes. Incident uveitis (8 of 28, 29%), the only vector-related adverse event, resulted in no attributable vision sequelae and was related to vector dose: 5 of 7 (71%) higher-dose eyes vs 3 of 21 (14%) low-, medium-, or high-dose eyes (P < .001). Incident uveitis requiring treatment was associated with increased serum AAV2 neutralizing antibody titers (p=0.007) but not serum AAV2 polymerase chain reaction. Improvements of ≥15-letter BCVA occurred in some treated and fellow eyes of groups 1 and 2 and some surrogate study and fellow eyes of natural history subjects. All study eyes (BCVA ≥20/40) in group 3 lost ≥15 letters within the first year despite treatment. G11778A LHON gene therapy has a favorable safety profile. Our results suggest that if there is an efficacy effect, it is likely small and not dose related. Demonstration of efficacy requires randomization of patients to a group not receiving vector in either eye.

Toxic and Nutritional Optic Neuropathies-An Updated Mini-Review.

Optic neuropathies constitute a group of conditions with various etiologies and might be caused by different factors; we can distinguish the genetic and acquired causes of optic neuropathies. Even though the symptoms are not highly specific, this condition is primarily characterized by unilateral or bilateral vision loss with worsening color detection. The loss may be acute or gradual depending on the causation. In this article, we included a specification of toxic optic neuropathy (TON) mainly triggered by alcohol abuse and also the usage of other substances, including drugs or methanol, as well as intoxication by metals, organic solvents, or carbon dioxide. Nutritional deficiencies, vitamin absorption disorder, and anemia, which usually appear during excessive alcohol intake, and their effect on the etiology of the optic neuropathy have been likewise discussed.

A Rare Case of Bilateral Post Intravitreal Avastin Endophthalmitis with Bilateral Good Visual Outcome – A Case Report

This is a case report of post intravitreal injection endophthalmitis encountered at the University Teaching Hospitals–Eye Hospital in Lusaka, Zambia. Endophthalmitis is a clinical diagnosis made when intraocular inflammation involving both the anterior and posterior chambers is attributable to bacterial or fungal infection. Post injection endophthalmitis is a dreaded complication that occurs following intraocular surgery or procedures such as intravitreal administration of anti-vascular endothelial growth factors or corticosteroids. We attended to a rare case of bilateral post intravitreal injection endophthalmitis in a 51- year- old female patient who presented with bilateral severe pain and acute visual loss in both eyes following intravitreal injection of Avastin (bevacizumab) the previous day. On examination, there was severely decreased visual acuity from 6/36 right eye and 6/60 left eye to hand movement in both eyes. There was also corneal haziness, fibrin in the anterior chambers, hypopyon and vitreous cells in both eyes. A clinical diagnosis of bilateral post-injection endophthalmitis was made. There was immediate administration of intravitreal antibiotics of Vancomycin 1.0mg/0.1mL and Ceftazidime 2.25mg/0.1mL with intravitreal Dexamethasone 0.4mg/0.1ml stat dose and systemic ciprofloxacin 750mg 12 hourly for 7 days. Due to prompt diagnosis and treatment vision recovery was excellent in both eyes and both eyes were preserved.

Transient Bilateral Visual Loss as the Presenting Symptom of High-Altitude Ascent-Related Cytotoxic Lesion of the Corpus Callosum.

Transient Bilateral Visual Loss as the Presenting Symptom of High-Altitude Ascent-Related Cytotoxic Lesion of the Corpus Callosum.

Bilateral blindness after uneventful brolucizumab injection for macular degeneration

BackgroundWe report a very severe case of bilateral panuveitis and ischemic vasculitis with possible perineural inflammation, which followed bilateral intravitreal brolucizumab administration in a patient with neovascular age-related macular degeneration (nAMD).Case presentationOn December 11, 2020, a 81-year-old woman presented with severe bilateral loss of vision. Eight days earlier, she had received uneventful bilateral injection of brolucizumab, a novel anti-vascular endothelial growth factor (VEGF) single-chain variable region (scFv) recombinant protein drug, for treatment of neovascular age-related macular degeneration (nAMD).Slit-lamp examination revealed signs of a bilateral panocular vasculitis with ischemia. Scanning laser ophthalmoscopy of her left eye revealed marked vascular sheathing.T1 fat-saturated post-contrast images of the orbit revealed a higher-than-normal signal of the choroid, with localized choroidal detachment. Additionally, pathologic enhancement was visible around the optic nerve in the orbit, which was interpreted as vasculitis. Due to the severe bilateral panuveitis with vasculitis, an additional vitreous tap was obtained, which revealed elevated levels of interleukin six and interleukin ten.ConclusionsTo our knowledge, this is the first documented case showing both panuveitis and ischemic vasculitis with possible perineural inflammation. We do not recommend performing bilateral brolucizumab injections until more data is available regarding the mechanism of brolucizumab-induced vasculitis. From a clinical point of view, we find it difficult to justify the use of brolucizumab when there are other well-known agents, such as ranibizumab and aflibercept, which have better safety profiles and comparable efficacy.

Vision Loss Secondary to COVID-19 Associated Bilateral Cerebral Venous Sinus Thromboses.

A young, morbidly obese woman with recent SARS-CoV-2 infection requiring hospitalization presented with visual and neurologic complications secondary to bilateral cerebral venous sinus thromboses. With elevated intracranial pressure and severe papilledema, she rapidly progressed to complete bilateral vision loss despite anticoagulation, therapeutic lumbar punctures with lumbar drain, bilateral optic nerve sheath fenestrations, and endovascular thrombectomy. It is possible that obese patients with a SARS-CoV-2 infection may be at greater risk of hypercoagulable cerebrovascular complications. It is impossible to know if an even more rapid response would have led to a different outcome, but we report this case in the hope that publishing this and similar cases may result in improved treatment protocols to preserve vision.

A New Era for the Early and Non-Invasive Diagnosis of Giant Cell Arteritis: The Use of Fast-Track Ultrasound in Clinical Practice

Background: The assessment of giant cell arteritis (GCA) in fast-track assessment clinics (FTA) including the use of ultrasound (US) is becoming the preferred practice in specialized centers. Methods: Patients with suspected GCA referred to the FTA of the Rheumatology Department, University of Pavia, Italy, between 2016 and 2021 were included to analyze the clinical and US findings. Results: A total of 553 US examinations were performed on 347 patients. A total of 246 were female (71%), and the mean age was 73 ± 12. Of these, 287 US on newly referred patients led to a confirmed diagnosis of GCA in 111 (39%). The sensitivity of US was 81.98% (95% CI 73.55–88.63%), and the specificity 99.43% (95% CI 96.88–99.99%). Only 4 patients required temporal artery biopsy. The most specific symptoms to inform the pre-test probability of GCA and differentiate from patients with other conditions were: jaw or tongue claudication, scalp tenderness, and bilateral visual loss. Headache was not reported in 33% of patients. Systemic symptoms were significantly more frequent in GCA (42.3%), together with combinations of cranial, systemic, and/or polymyalgia rheumatica symptoms. Out of 88 patients, there were 52% with a confirmed relapse. Of these, 67% had a positive US. Conclusion: The use of FTA in clinical practice ensures an early diagnosis, avoiding invasive procedures for the patient. Our data support the increasingly recognized adjunctive role of US in the monitoring of GCA.

Bitemporal peripapillary hemorrhages: Toxic-ischemic optic neuropathy caused by ethanol and cocaine abuse

A 36-year-old man presented complaining of bilateral painless vision loss. He was admitted with chronic ethanol abuse, as well as sporadic cocaine consumption three days before symptom onset. General medical evaluation dismissed cerebral and cardiovascular events. Blood tests revealed folic acid deficiency. Visual acuity (VA) was count fingers in both eyes (OU). Fundoscopic findings included remarkable bitemporal peripapillary hemorrhages. A diagnosis of toxic-ischemic optic neuropathy was made. The hemorrhages resolved after three weeks, with VA recovering to 20/20 OU. The sequelae included bitemporal peripapillary retinal fiber loss on optical coherence tomography, and central scotomas observed on visual field tests. This is the first report of cocaine as a triggering agent for a classical presentation of toxic optic neuropathy and the presence of peripapillary hemorrhages in its initial stages.

Vestibular Rehabilitation Telehealth During the SAEA-CoV-2 (COVID-19) Pandemic.

During the COVID-19 pandemic, physical therapists transitioned to provide telehealth in the United States. We sought to determine the experiences of physical therapists delivering telerehabilitation for vestibular disorders including barriers, preferences, and concerns. A survey was created using the results of a focus group and previously published studies. The survey was distributed across social media sites and through email- the link was sent to the orthopedic, neurologic, and geriatric academies of the American Physical Therapy Association list serves. The email was also shared with each of the 50 state chapters of the American Physical Therapy Association. The survey was broken down into five sections: demographic information, physical therapists' general impressions of telehealth, physical therapists' comfort level treating various vestibular diagnoses, and common barriers physical therapists experienced during telehealth sessions. There were 159 completed surveys. More than 80% of physical therapists surveyed agreed that telehealth was an effective platform for vestibular physical therapy. When asked whether physical therapists felt the patient had similar health outcomes with telehealth versus clinic care 68% of physical therapists agreed. For the physical therapists who treated posterior or horizontal canal benign paroxysmal positional vertigo via telehealth, more than 50% were comfortable treating these conditions via telehealth. In analyzing common peripheral vestibular diagnoses treated via telehealth including bilateral vestibular loss, Meniere's disease, and vestibular neuritis more than 75% of the physical therapists reported comfort treating these diagnoses. Similarly, more than 75% of physical therapists who treated central vestibular diagnoses- including mild traumatic brain injury and vestibular migraine- via telehealth reported being comfortable treating these diagnoses. Physical therapists reported several barriers to tele healthcare ranging from concerns about testing balance with no caregiver present (94%) to challenges with providing a written home exercise program (33%). Physical therapists report that telehealth is a viable mechanism for providing rehabilitation for persons with balance and vestibular disorders. For common diagnoses, most physical therapists were comfortable treating vestibular disorders via telehealth. While barriers remain including maintaining patient safety and being able to complete a thorough vestibular exam, telehealth for vestibular physical therapy services holds promise for the delivery of virtual care.

Selective Inner Hair Cell Loss in a Neonate Harbor Seal (Phoca vitulina).

Simple SummaryCongenital hearing loss (i.e., hearing impairment present at birth) is recognized in humans and other terrestrial species, but there is a lack of information on congenital malformations and associated hearing loss in pinnipeds (seals, sea lions, and walruses). Baseline knowledge on marine mammal inner ear malformations is essential to differentiate between congenital and acquired abnormalities, which may be caused by infectious agents, age, or anthropogenic interactions, such as noise exposure. Analysis of the cochlea of a neonate harbor seal (Phoca vitulina) revealed bilateral loss of inner hair cells (sensory cells responsible for transducing the auditory signal) while the outer hair cells (sensory cells responsible for sound amplification and frequency selectivity and sensitivity) were intact. The selective inner hair cell loss (up to 84.6% of loss) was more severe in the basal turn, where the high frequencies are encoded. Potential causes and consequences are discussed. This is the first report of a case of selective inner hair cell loss in a marine mammal neonate, likely congenital.Congenital hearing loss is recognized in humans and other terrestrial species. However, there is a lack of information on its prevalence or pathophysiology in pinnipeds. It is important to have baseline knowledge on marine mammal malformations in the inner ear, to differentiate between congenital and acquired abnormalities, which may be caused by infectious pathogens, age, or anthropogenic interactions, such as noise exposure. Ultrastructural evaluation of the cochlea of a neonate harbor seal (Phoca vitulina) by scanning electron microscopy revealed bilateral loss of inner hair cells with intact outer hair cells. The selective inner hair cell loss was more severe in the basal turn, where high-frequency sounds are encoded. The loss of inner hair cells started around 40% away from the apex or tip of the spiral, reaching a maximum loss of 84.6% of hair cells at 80–85% of the length from the apex. Potential etiologies and consequences are discussed. This is believed to be the first case report of selective inner hair cell loss in a marine mammal neonate, likely congenital.

Bilateral phacoemulsification of cataract: the opinion of foreign ophthalmologists

Рurpose: to present the opinion of foreign ophthalmic surgeons on simultaneous bilateral phacoemulsification of cataract (SBPEC) by analyzing literature data. We performed an analysis of papers listed by Pubmed in 2000–2020 which contained expert assessments of SBPEC effectiveness based on polling. Ophthalmic surgeons were offered special questionnaires largely close in content, which were designed to establish the rating of factors that affected the respondents’ decision for or against the surgery. Our results indicate that, depending on the country, from 13.9 to 86 % of ophthalmic surgeons practice SBPEC, while from 14.0 to 67.2 % refrain from using this technology. The surveys revealed three major factors in favor of SBPEC — reduced number of clinical visits, the patient’s convenience during rehabilitation, and a high risk of complications after a second general anesthesia. The main factors against SBPEC are the risk of endophthalmitis (noted by 69–73 % of respondents), the absence of information on the postoperative refractive result in the first eye, which could determine the choice of the intraocular lens on the second eye (74–80 %), the risk of bilateral vision loss (73–79 %), as well as possible forensic problems (52–58 %).Conclusion. The surveying highlights certain negative factors that need to be overcome in order for SBPEC to become more widespread. Raising the awareness of SBPEC practice and approval by the ophthalmic community is essential for a sustainable culture change regarding this technology. To achieve this aim, standardization of the SBPEC procedure is needed, followed by the development of training manuals and protocols for surgical intervention.

FATAL BILATERAL ORBITAL INVOLVEMENT IN CASE OF ROCM IN A YOUNG DIABETIC PATIENT WITH COVID-19 INFECTION: A RARE CASE REPORT

The second wave of COVID-19 in India was associated with higher incidence of Mucormycosis. We report a rare case of 40-year-old Asian male, with Type 2 diabetes mellitus who presented with bilateral sudden loss of vision, ptosis, proptosis, total ophthalmoplegia and central retinal artery occlusion. Computed tomography followed by magnetic resonance imaging was suggestive of bilateral sinusitis, orbital cellulitis, optic neuritis and gross intracranial involvement. Considering his general condition and guarded prognosis for survival, exenteration was deferred. After detailed literature research, we found very few reports of bilateral orbital involvement in cases of COVID-19 associated ROCM. Even after early diagnosis and prompt treatment of ROCM, patient succumbed to the illness. Covid 19 associated bilateral rhino-orbital-cerebral mucormycosis may be a marker of mortality in the affected population.

Bilateral vision loss on programmed hemodialysis (clinical observation)

The most common complication of hemodialysis is blood pressure decrease, which is an ischemic optic neuropathy risk factor. The article presents a case study of sequential bilateral ischemic optic neuropathy with the development of amaurosis as a result of arterial hypotension against the background of programmed hemodialysis. Differential diagnosis in bilateral visual impairment is discussed.

A case report of occlusal reconstruction using an implant prosthesis in a patient with deep overbite and mandibular bilateral molar loss

A case report of occlusal reconstruction using an implant prosthesis in a patient with deep overbite and mandibular bilateral molar loss

What's new in neuromyelitis optica spectrum disorder treatment?

Optic neuritis, an optic nerve inflammatory disease presenting with acute unilateral or bilateral visual loss, is one of the core symptoms of neuromyelitis optica spectrum disorder (NMOSD). The diagnosis of NMOSD-related optic neuritis is challenging, and it is mainly based on clinical presentation, optical coherence tomography, magnetic resonance imaging scans, and the status of serum aquaporin-4 antibodies. In the pathogenesis, aquaporin-4 antibodies target astrocytes in the optic nerves, spinal cord and some specific regions of the brain eliciting a devastating autoimmune response. Current pharmacological interventions are directed against various steps within the immunological response, notably the terminal complement system, B-cells, and the pro-inflammatory cytokine Interleukin 6 (IL6). Conventional maintenance therapies were off-label uses of the unspecific immunosuppressants azathioprine and mycophenolate mofetil as well as the CD20 specific antibody rituximab and the IL6 receptor specific antibody tocilizumab. Recently, four phase III clinical trials demonstrated the safety and efficacy of the three novel biologics eculizumab, inebilizumab, and satralizumab. These monoclonal antibodies are directed against the complement system, CD19 B-cells and the IL6 receptor, respectively. All three have been approved for NMOSD in the US and several other countries worldwide and thus provide convincing treatment options.

Autoimmune retinopathy with associated anti-retinal antibodies as a potential immune-related adverse event associated with immunotherapy in patients with advanced cutaneous melanoma: case series and systematic review

ObjectiveTo demonstrate the spectrum of autoimmune retinopathy (AIR) associated with immunotherapy for advanced cutaneous melanoma.Methods and analysisRetrospective chart review on patients with advanced cutaneous melanoma who developed AIR after initiating...

Unsupervised Real-World Image Super-Resolution via Dual Synthetic-to-Realistic and Realistic-to-Synthetic Translations

Due to the challenges of collecting paired low-resolution (LR) and high-resolution (HR) images in real-world scenarios, most existing deep convolutional neural network (CNN)-based single image super-resolution (SR) models are trained with artificially synthesized LR-HR image pairs. However, the domain gap between the synthetic data for model training and the realistic data for testing degrades SR performance significantly, which discourages the application of SR models in practice. One possible solution is to learn from unpaired real-world LR and HR images for their accessibility. Predominant strategies are mainly based on unsupervised domain translation. Despite great advances, there are still noticeable domain gaps between the realistic-like/synthetic-like images generated by unpaired translation and the true realistic/synthetic ones. To address this problem, this letter proposes an effective unsupervised SR framework based on dual synthetic-to-realistic and realistic-to-synthetic translations, namely DTSR. Specifically, to bridge the domain gap between testing and training data, the SR model is optimized using HR images and their realistic-like LR counterparts produced by the synthetic-to-realistic translation. In turn, we propose to narrow the domain gap further via applying the realistic-to-synthetic translation to realistic LR images prior to super-resolving, which also makes the SR model super-resolve simpler examples in testing relative to model training. Moreover, focal frequency and bilateral filtering losses are particularly introduced into DTSR for better details restoration and artifacts suppression. Extensive experiments show that our DTSR outperforms several state-of-the-art models in terms of both quantitative and qualitative comparisons.

Bilateral Vision Loss From Varicella Zoster Virus-Associated Giant Cell Arteritis.

Xie, Jim S. BHSc; Yang, Stephanie P. MD, MSc; Munoz, David G. MD; Micieli, Jonathan A. MD, CMEditor(s): Avery, Robert DO; Golnik, Karl C. MD; Froment, Caroline MD, PhD; Wang, An-Guor MD Author Information