Blinding Optic Neuropathy Associated With Carboplatin Therapy: A Case Report and Literature Review

Various forms of cancer and chemotherapeutics are associated with optic neuropathy. Cisplatin is a platinum analogue chemotherapeutic commonly associated with ocular toxicity among many other serious adverse effects. Carboplatin is a more chemically stable platinum analogue that is generally better tolerated with a comparatively favorable side effect profile. There are very few reports of carboplatin precipitating optic neuropathy. This case report describes a rare occurrence of carboplatin-induced blinding optic neuropathy. We treated a patient receiving carboplatin for neuroendocrine bladder cancer who developed rapidly progressive bilateral optic neuropathy over the course of three days. Upon evaluation at our clinic, his visual acuity had declined to light perception only and 20/60 in his left and right eye, respectively. Carboplatin therapy was immediately held and steroids were initiated. Despite the intervention, the patient's visual deficits have not improved at the one-year follow-up. Although the mechanism by which carboplatin causes ocular toxicity remains speculative, arterial ischemia appears to be the likely mechanism given the irreversible nature of visual decline. As demonstrated by our patient's course, irreversible vision loss despite high-dose steroid intervention necessitates expeditious recognition and management of this rare adverse effect. ​​​​​.

A Pair of Siblings With Wolfram Syndrome: A Review of the Literature and Treatment Options

Wolfram syndrome (WS) is a rare genetic disorder typically characterized by juvenile onset diabetes mellitus, optic atrophy, hearing loss, diabetes insipidus, and neurodegeneration. There would be a high index of clinical suspicion for WS when clinical manifestations of type 1 diabetes and optic atrophy present together. Genetic analysis is often required to confirm the diagnosis. We describe a pair of Chinese siblings diagnosed with WS at ages 20 and 24 years, respectively. DNA sequencing of the WFS1 gene which encodes for Wolframin ER Transmembrane Glycoprotein identified a heterozygous nonsense variant NM_006005.3: c.1999C>T p.(Gln667*) and a heterozygous missense variant c.2170C>T p.(Pro724Ser) in exon 8 of the gene for both siblings. There is no curative treatment for WS and management of this debilitating disease is aimed at treating individual clinical manifestations, slowing disease progression, and improving quality of life. Treatment with liraglutide, a glucagon-like-peptide-1 receptor agonist, and tauroursodeoxycholic acid was started for the younger sibling, the proband. There was reduction in insulin requirements and improvement in glycemic control. The other sibling was not offered liraglutide due to her complex treatment regimen for end-organ failure. Genetic testing is a valuable tool to detect WS early to allow precise and prompt diagnosis, thereby facilitating the coordinated care from a multidisciplinary team of clinicians.

Two Cases of Wolfram Syndrome Who Were Initially Diagnosed With Type 1 Diabetes

Objective

Early diagnosis of syndromic monogenic diabetes allows for proper management and can lead to improved quality of life in the long term. This report aimed to describe 2 genetically confirmed cases of Wolfram syndrome, a rare endoplasmic reticulum disorder characterized by insulin-dependent diabetes mellitus, optic nerve atrophy, and progressive neurodegeneration.

Case Report

A 16-year-old Caucasian male patient and a 25-year-old Caucasian female patient with a history of diabetes mellitus and optic nerve atrophy presented at our medical center. Both patients were initially diagnosed with type 1 diabetes but negative for islet autoantibodies. Their body mass indexes were under 25 at the diagnosis. Their history and presentation were highly suspicious for Wolfram syndrome.

Discussion

The genetic tests revealed a known Wolfram syndrome 1 (WFS1) pathogenic variant (homozygous) in the 16-year-old male patient and 2 known WFS1 pathogenic variants (compound heterozygous) in the 25-year-old female patient with diabetes mellitus and optic nerve atrophy, confirming the diagnosis of Wolfram syndrome. The first patient had a moderate form, and the second patient had a milder form of Wolfram syndrome.

Conclusion

Providers should consider monogenic diabetes genetic testing, including WFS1 gene, for patients with early-onset diabetes who are negative for islet autoantibodies and lean. Two patients described in this article could have been diagnosed with Wolfram syndrome before they developed optic nerve atrophy. Genetic testing is a valuable tool for the early detection of Wolfram syndrome, which leads to proper management and improved quality of life in patients with this rare medical condition.

Early Intervention and Lifelong Treatment with GLP1 Receptor Agonist Liraglutide in a Wolfram Syndrome Rat Model with an Emphasis on Visual Neurodegeneration, Sensorineural Hearing Loss and Diabetic Phenotype

Wolfram syndrome (WS), also known as a DIDMOAD (diabetes insipidus, early-onset diabetes mellitus, optic nerve atrophy and deafness) is a rare autosomal disorder caused by mutations in the Wolframin1 (WFS1) gene. Previous studies have revealed that glucagon-like peptide-1 receptor agonist (GLP1 RA) are effective in delaying and restoring blood glucose control in WS animal models and patients. The GLP1 RA liraglutide has also been shown to have neuroprotective properties in aged WS rats. WS is an early-onset, chronic condition. Therefore, early diagnosis and lifelong pharmacological treatment is the best solution to control disease progression. Hence, the aim of this study was to evaluate the efficacy of the long-term liraglutide treatment on the progression of WS symptoms. For this purpose, 2-month-old WS rats were treated with liraglutide up to the age of 18 months and changes in diabetes markers, visual acuity, and hearing sensitivity were monitored over the course of the treatment period. We found that treatment with liraglutide delayed the onset of diabetes and protected against vision loss in a rat model of WS. Therefore, early diagnosis and prophylactic treatment with the liraglutide may also prove to be a promising treatment option for WS patients by increasing the quality of life.

[Modern treatment of different forms of optic nerve atrophy]

Optic nerve atrophy (ONA) is one of the most common causes of blindness and low vision in the world. The disease occurs in 60-68% of cases. The causes of optic nerve atrophy are diverse: inflammatory and vascular diseases of the optic nerve and retina, glaucoma, atherosclerosis of the main vessels of head and neck, diseases of central nervous system, intoxication of various etiologies, as well as congenital and hereditary diseases. The literature review presents data on the diagnosis and classification of optic nerve atrophy, as well as on drug and non-drug treatment in combination with physiotherapy.

Retinal Racemose Hemangioma With Optic Neuropathy in a Child

The aim of this study is to report an unusual case of retinal racemose haemangioma (RRH) in a child resulting in optic neuropathy and its optical coherence tomography angiography (OCT-A) findings. This is a retrospective case report.

For almost a year, a 13-year-old girl experienced gradual, painless, generalized blurred vision in her right eye. Visual acuity was 6/60 with a positive relative afferent pupillary defect (RAPD) in her right eye. The right-eye fundus showed enlarged and tortuous retinal vessels extending from the optic disc to all four quadrants, including the juxta foveal region. OCT analysis revealed distortion in the region of enlarged vessels with minimal retinal fluid while OCT-A of the macula area demonstrated dilated and tortuous vessels in the superficial layers of the retina. Right intra-orbital vascular channels surrounding the optic nerve with optic nerve atrophy and gliosis were detected on magnetic resonance imaging angiography/venography (MRA/MRV). The cerebral angiogram reported an abnormal tangle of small vessels within the right orbit that received supply from a dilated right ophthalmic artery indicating the presence of retro-orbital arteriovenous malformation (AVM). She was then referred to the neurosurgeon and a decision was made not to embolize or resect the dilated vessel as this might lead to occlusion of the ophthalmic artery and thus worsen her vision.

RRH may present in the paediatric age group, and optic nerve atrophy is one of the disease manifestations. OCT-A is a less invasive diagnostic option compared to fundus fluorescein angiography (FFA) for diagnosis and monitoring of disease progression.

[A novel frameshift NDUFV1 mutation in a child with the phenotype of optic nerve atrophy]

OBJECTIVE

To investigate the pathogenic gene in a child with optic atrophy and analyze the influence of this gene mutation on protein structure.

OBJECTIVE

We collected the clinical record of the 13-year-old girl and her relatives. The child received examinations of the visual acuity, visual field, fundus, OCT, visual-evoked potential (VEP) and the nerve system, underwent brain MRI and was followed up for 1 year. Genomic DNA was extracted from the peripheral blood of the child and her parents for next-generation sequencing of the whole exon. The pathogenic gene mutation was identified and the resultant changes in the protein structure was analyzed.

OBJECTIVE

The patient presented with impaired vision and optic nerve atrophy in both eyes with low amplitude of VEP, but did not show dystonia or pyramidal tract symptom. Brain MRI detected no leukodystrophy. Genetic analysis suggested a heterozygous c.53_54delTG mutation in exon 1 in the NDUFV1 gene of complex I, which caused a frameshift starting with the codon valine 18, thus changing the amino acid to an Alanine residue and creating a premature stop codon at position 20 of the new reading frame (p.Val18AlafsX20). A heterozygous for c.1162+4A>C: IVS8 + 4A>C in intron 8 was also found. Protein structure analysis showed the missing of important structure of NDUFV1 subunit in complex I.

OBJECTIVE

We identified a novel NDUFV1 mutation in a child with optic nerve atrophy. This finding may provide further insight into the genotype-phenotype correlations for NDUFV1 gene.

RERE deficiency causes retinal and optic nerve atrophy through degeneration of retinal cells

BACKGROUND

The arginine-glutamic acid dipeptide repeats gene (RERE) encodes a nuclear receptor coregulator that modulates gene expression through its interaction with transcriptional machinery. In humans, RERE deficiency causes neurodevelopmental disorder with or without structural defects of the brain, eye, heart, and kidney (NEDBEH). Ophthalmological defects are seen in approximately one third of individuals with NEDBEH and in RERE-deficient mice which can serve as a useful animal model.

RESULTS

In mice, RERE is expressed in a subset of retinal ganglion cells (RGC), the lens epithelium, and the ciliary body during the embryonic period. RERE expression expands into the outer nuclear layer and the inner nuclear layer during the postnatal period. RERE-deficient mice have retinal and optic nerve atrophy. We show that RERE deficiency causes progressive loss of retinal cells and apoptosis of retinal cells in the ganglion cell layer as early as E17.5. The number of RGCs is also reduced in RERE-deficient embryos and mice.

CONCLUSIONS

We conclude that RERE is required to control the apoptosis of retinal cells in the developing retina, and that RERE deficiency results in the retina atrophy through degeneration of the retinal cells and optic nerve atrophy through the loss of RGCs.

Clinical assessment and FGFR2 mutation analysis in a Chinese family with Crouzon syndrome: A case report

RATIONALE

Crouzon syndrome is an autosomal dominant genetic disorder caused by mutations in fibroblast growth factor receptor 2 (FGFR2) and one of the most common types of craniosynostosis. Here we report the detection of FGFR2 mutation and its related clinical findings in 2 patients with Crouzon syndrome from a Chinese family.

PATIENT CONCERNS

We report a case of a 28-year-old male patient presented with the chief complaint of gradually blurring of his eyes over the last 6 months before visiting our clinics. History revealed low visual acuity in his right eye since childhood. Physical examination showed that both the patient and his mother have the appearance of craniofacial dysostosis, mandibular prognathism, ocular proptosis, short superior lip, scoliosis, and thoracic deformity.

DIAGNOSIS

Auxiliary examinations lead to the diagnosis of Crouzon syndrome with binocular optic atrophy, myelinated retina nerve fibers, and ametropia in both eyes, and amblyopia in the right eye of the male patient. The molecular genetic analysis confirmed the diagnosis by detecting a heterozygous pathogenic mutation c.1026C > G (C342W) in exon 10 of FGFR2 in both the patient and his mother, but not in any of the unaffected family members.

INTERVENTIONS AND OUTCOMES

None.

LESSONS

Our study confirms the presence of optic nerve atrophy in patients with Crouzon syndrome carrying FGFR2 C342W mutations and indicates that MRI and funduscopy should be performed to examine the optic nerve changes for patients with Crouzon syndrome.

Neuro-Ophthalmological Manifestations of Craniosynostosis: Current Perspectives

Craniosynostosis, a premature fusion of cranial sutures that can be isolated or syndromic, is a congenital defect with a broad, multisystem clinical spectrum. The visual pathway is prone to derangements in patients with craniosynostosis, particularly in syndromic cases, and there is a risk for permanent vision loss when ocular disease complications are not identified and properly treated early in life. Extensive advancements have been made in our understanding of the etiologies underlying vision loss in craniosynostosis over the last 20 years. Children with craniosynostosis are susceptible to interruptions in visual input arising from strabismus, refractive errors, and corneal damage; any of these aberrations can result in understimulation of the visual cortex during childhood neurodevelopment and permanent amblyopia. Elevated intracranial pressure resulting from abnormal cranial shape or volume can lead to papilledema and, ultimately, optic atrophy and vision loss. A pediatric ophthalmologist is a crucial component of the multidisciplinary care team that should be involved in the care of craniosynostosis patients and consistent ophthalmologic follow-up can help minimize the risk to vision posed by such entities as papilledema and amblyopia. This article aims to review the current understanding of neuro-ophthalmological manifestations in craniosynostosis and explore diagnostic and management considerations for the ophthalmologist taking care of these patients.

Neurofilament light chain as biomarker in idiopathic intracranial hypertension

BACKGROUND

Damage of the optic nerve is the major complication of idiopathic intracranial hypertension. A biomarker indicative for optic nerve damage would help identifying high-risk patients requiring surgical procedures. Here, we studied the potential of cerebrospinal fluid neurofilament to predict idiopathic intracranial hypertension-induced optic nerve damage.

METHODS

In two centers, serum and cerebrospinal fluid of 61 patients with clinically suspected idiopathic intracranial hypertension were prospectively collected. Neurofilament concentrations were measured and related to ophthalmological assessment.

RESULTS

The average cerebrospinal fluid neurofilament concentration in patients with moderate and severe papilledema was increased compared to patients with minor and no papilledema (1755 ± 3507 pg/ml vs. 244 ± 102 pg/ml; p < 0.001). Cerebrospinal fluid neurofilament concentrations correlated with the maximal lumbar puncture opening pressure (r = 0.67, p < 0.001). In patients fulfilling the Friedman criteria for idiopathic intracranial hypertension with or without papilledema (n = 35), development of bilateral visual field defects and bilateral atrophy of the optic nerve were associated with increased average age-adjusted cerebrospinal fluid neurofilament concentrations. At last follow-up (n = 30), 8/13 of patients with increased, but only 3/17 with normal, cerebrospinal fluid neurofilament had developed bilateral visual field defects and/or bilateral optic nerve atrophy resulting in a sensitivity of 72.7% and a specificity of 73.7% of cerebrospinal fluid neurofilament to detect permanent optic nerve damage.

CONCLUSIONS

Cerebrospinal fluid neurofilament is a putative biomarker for optical nerve damage in idiopathic intracranial hypertension.

Mouse Nr2f1 haploinsufficiency unveils new pathological mechanisms of a human optic atrophy syndrome

Optic nerve atrophy represents the most common form of hereditary optic neuropathies leading to vision impairment. The recently described Bosch‐Boonstra‐Schaaf optic atrophy (BBSOA) syndrome denotes an autosomal dominant genetic form of neuropathy caused by mutations or deletions in the NR2F1 gene. Herein, we describe a mouse model recapitulating key features of BBSOA patients—optic nerve atrophy, optic disc anomalies, and visual deficits—thus representing the only available mouse model for this syndrome. Notably, Nr2f1‐deficient optic nerves develop an imbalance between oligodendrocytes and astrocytes leading to postnatal hypomyelination and astrogliosis. Adult heterozygous mice display a slower optic axonal conduction velocity from the retina to high‐order visual centers together with associative visual learning deficits. Importantly, some of these clinical features, such the optic nerve hypomyelination, could be rescued by chemical drug treatment in early postnatal life. Overall, our data shed new insights into the cellular mechanisms of optic nerve atrophy in BBSOA patients and open a promising avenue for future therapeutic approaches.

The use of mesenchymal stem cells for the treatment of progressive retinal diseases: a review

Some ocular diseases, such as dystrophies, retinal and macular degeneration, optic nerve atrophy, and Stargardt disease, are progressive and irreversible. In this review, we focus on the use of mesenchymal stem cells (MSCs) in the treatment of these diseases. In animal studies, MSC transplantation significantly delayed retinal degeneration, led to the regeneration of cone cells, and supported the survival of retinal ganglion cells and axon regeneration. In clinical practice, patients with Behcet's disease with retinal vasculitis who received MSC injections experienced a decrease in retinal vasculitis but no improvement in vision acuity. Nonetheless, there is no evidence that MSCs are carcinogenic, and they even reduce the size of tumors in vitro. Furthermore, MSCs do not trigger the immune response.

An N-terminal heterozygous missense CASK mutation is associated with microcephaly and bilateral retinal dystrophy plus optic nerve atrophy

Heterozygous loss-of-function mutations in the X-linked gene CASK are associated with mental retardation and microcephaly with pontine and cerebellar hypoplasia (MICPCH) and ophthalmological disorders including optic nerve atrophy (ONA) and optic nerve hypoplasia (ONH). Recently, we have demonstrated that CASK^(+/-) mice display ONH with 100% penetrance but exhibit no change in retinal lamination or structure. It is not clear if CASK loss-of-function predominantly affects retinal ganglion cells, or if other retinal cells like photoreceptors are also involved. Here, we report a heterozygous missense mutation in the N-terminal calcium/calmodulin-dependent kinase (CaMK) domain of the CASK protein in which a highly conserved leucine is mutated to the cyclic amino acid proline. In silico analysis suggests that the mutation may produce destabilizing structural changes. Experimentally, we observe pronounced misfolding and insolubility of the CASK^L209P protein. Interestingly, the remaining soluble mutant protein fails to interact with Mint1, which specifically binds to CASK's CaMK domain, suggesting a mechanism for the phenotypes observed with the CASK^L209P mutation. In addition to microcephaly, cerebellar hypoplasia and delayed development, the subject with the L209P mutation also presented with bilateral retinal dystrophy and ONA. Electroretinography indicated that rod photoreceptors are the most prominently affected cells. Our data suggest that the CASK interactions mediated by the CaMK domain may play a crucial role in retinal function, and thus, in addition to ONH, individuals with mutations in the CASK gene may exhibit other retinal disorders, depending on the nature of mutation.

Outcomes of pressure-induced cranial neuropathies from allergic fungal rhinosinusitis

OBJECTIVES

Allergic fungal rhinosinusitis (AFRS) may present with significant bone erosion of the orbital walls or cranial base. Although proptosis is fairly common, cranial neuropathies are rarely reported. The objectives of this study are to describe strategies for AFRS-induced neuropathies and evaluate ophthalmologic outcomes following endoscopic sinus surgery.

STUDY DESIGN

Case series with chart review.

SETTING

Tertiary referral center.

SUBJECT AND METHODS

A retrospective review identified 9 patients treated from 2008 to 2014 with AFRS-induced cranial neuropathies. Data regarding patient demographics, preoperative imaging, ophthalmologic symptoms, surgical intervention, histopathologic findings, and postoperative sinonasal and ophthalmologic outcomes were recorded.

RESULTS

Patients with AFRS (average age, 38 years) presented with optic neuropathy or abducens nerve palsy. Clinical presentation included unilateral visual loss secondary to optic nerve compression (n=5), diplopia from unilateral (n=2) or bilateral (n=1) abducens nerve palsy, and bitemporal hemianopsia secondary to optic chiasm compression (n=1). On average, the duration of ocular symptoms was 17 days. All patients underwent endoscopic surgical decompression of the sinuses and oral steroid therapy. Two individuals had an additional optic nerve decompression at the time of surgery. Seven patients had complete return of nerve function, whereas 2 had partial recovery at an average of 5 weeks following surgery.

CONCLUSION

Bone erosion of the sphenoid sinus walls by AFRS can lead to compression of surrounding neural structures producing cranial neuropathies. Identification of these symptoms and prompt surgical decompression and removal of disease, along with aggressive medical therapy, provided excellent outcomes in the current series of patients.

Clinical characteristics of nonglaucomatous optic disc cupping

Pathological optic disc cupping (ODC) is predominantly referred to as glaucoma; however, it is not only glaucoma that leads to pathological optic disc excavation. A number of other nonglaucomatous diseases also result in optic atrophy and excavation of the optic disc. Therefore, in the present study, the etiology of nonglaucomatous optic disc cupping (NGODC) was analyzed and differentiated from glaucomatous optic disc cupping (GODC). The morphology and clinical data of 19 eyes, from 12 patients exhibiting NGODC, were analyzed. Of the 12 cases, none were diagnosed with glaucoma, four presented with optic neuritis, one with Devic’s disease, one with Leber’s hereditary optic neuropathy, two with pituitary adenoma, one with basal ganglia cerebral hemorrhage, one with cilioretinal artery occlusion associated with central retinal vein occlusion, one with central retinal artery occlusion and the remaining patient exhibited optic nerve injuries. The key features that differentiated NGODC from GODC were the color of the optic disc rim and the correlation between visual field defects and the disc appearance. The focally notched disc also aided in distinguishing between the two disorders. The results of the present study indicated that it is critical to acknowledge that nonglaucomatous diseases also lead to ODC and that distinguishing between them is necessary.