Vitamin B3 Supplementation for Optic Neuropathies: A Comprehensive Review

Optic neuropathies, such as glaucoma, are some of the leading causes of irreversible blindness worldwide. There has been a lot of research for potential therapies that could attenuate and even reduce the impact of the pathological pathways that lead to the loss of retinal ganglion cells (RGCs). In recent years, vitamin B3 (nicotinamide) has gained some interest as a viable option for these neurodegenerative diseases due to its fundamental role in enhancing the mitochondria metabolism of the RGCs. This review focuses on elucidating the impact of vitamin B3 on retinal cells, especially when in a dysfunctional state like what happens in optic neuropathies, especially glaucoma. This review also summarizes the existing and future research on the clinical effects of vitamin B3 in these optic neuropathies, and determines appropriate recommendations regarding its dosing, efficacy, and eventual side effects.

Real-World Experience With Teprotumumab in Patients With Dysthyroid Optic Neuropathy

BACKGROUND

Teprotumumab, an insulin-like growth factor I receptor inhibitory antibody, improved proptosis, diplopia, inflammatory signs/symptoms, and quality of life in patients with active thyroid eye disease (TED) in clinical trials. The trials excluded patients with dysthyroid optic neuropathy (DON). Recently, many case reports and case series have reported the successful use of teprotumumab to treat DON. Here, we review the data from published cases and our clinical experience in treating patients having DON with teprotumumab.

METHODS

A literature search was conducted of patients with DON treated with teprotumumab from January 2020 through September 2022. Data from DON patients from the authors' (M.A.T. and C.A.B.) clinical practice were included. Primary outcome measure was mean (SD) improvements for visual acuity, color vision, and visual fields. Improvements in proptosis and clinical activity score (CAS) and diplopia were compared before and after teprotumumab administration.

RESULTS

Ten observational studies/case reports were identified along with 2 patients in our practice. In all, there were 24 active TED patients with DON (37 eyes) who were treated with teprotumumab. Mean (SD) age was 66.5 (13.6) years and 13 (54%) were females, disease duration ranged from 2 months to >15 years. 22/24 patients had none, minimal improvement or progression of visual loss with intravenous/oral corticosteroids, orbital decompression (n = 9), and orbital radiation (n = 2). There were 2 patients who received teprotumumab as the only therapy. Overall, 88% (21/24) reported improvement in visual acuity after teprotumumab and in 75% (18/24), improvement in vision was observed after just 2 infusions of teprotumumab. Three eyes had decompression surgery in close proximity to teprotumumab infusions and were excluded from analyses. Mean (SD) improvement in visual acuity was 3.73 lines (SD 3.74), range 2-15 lines in 33 eyes. The mean (SD) improvement in the mean deviation on visual field testing in 15 eyes was 5.6 db (3.0 db). Mean (SD) improvement in proptosis was 4.37 mm (SD: 2.11) (20 patients, 32 eyes); and clinical activity score: mean reduction of 5.1 (1.3) for 18 patients. Teprotumumab was well tolerated in all but one patient. Adverse events reported included fatigue, dysgeusia, hearing loss, nausea, hyperglycemia, and muscle spasms.

CONCLUSIONS

Teprotumumab is an effective treatment for DON in our experience and in published cases in whom treatment with steroids, surgery, or orbital radiation was unsuccessful.

Restoration of vision by combined experimental antithymocyte therapy, and orbital radiation with high-dose steroids for severe, acute, steroid-refractory, congestive thyroid orbitopathy

PURPOSE

We report diagnostic and therapeutic dilemmas in the difficult case of compressive optic neuropathy with severe visual acuity and visual field loss with subsequent visual recovery in both eyes, in a patient with Graves' orbitopathy (GO) by a combination of experimental antithymocyte therapy, orbital radiotherapy with high-dose steroids.

METHODS

A 72-year-old man presented with severe vision loss in both eyes. The visual symptoms had appeared over a year before the GO diagnosis. He was initially misdiagnosed with neuroborreliosis and optic neuritis based on brain and orbital magnetic resonance imaging. There was no exophthalmos. The ophthalmological examination included visual acuity, visual field, tonometry in primary and upgaze eye position, optical coherence tomography (OCT), pattern electroretinogram (PERG), pattern, and flash visual evoked potentials (PVEP and FVEP). The patient received experimental therapy with ATG, followed by high-dose of intravenous steroids and orbital radiotherapy.

RESULTS

Delayed VEP peaks became shorter after treatment. After systemic and local therapy lowering of intraocular pressure was achieved. Abnormal PERG has been found three months before ganglion cells atrophy was detected in OCT. Visual acuity and visual field improvement occurred in both eyes after therapy, despite partial left optic nerve atrophy. The patient regained full decimal visual acuity (1.0 right from as poor as 0.3  to 1.0 in the right eye and from hand movements to 0.9 in the left. Severe visual field loss with advanced absolute scotomata has improved to slight relative scotomata. The duration of follow-up time after the treatment was 4 months.

CONCLUSIONS

Intensive treatment of steroid-resistant Graves' orbitopathy (GO) may prevent total optic nerve atrophy. Despite severely advanced optic neuropathy, this report emphasizes the necessity of therapy even with nearly complete visual function loss hence there is always a possibility to regain full visual acuity and visual field. Patients with tense orbital septum may not present with significant exophthalmos, thus delaying the correct diagnosis of orbitopathy. A supporting sign of GO was the difference in intraocular pressure in the primary and upgaze eye positions. Electrophysiological examinations are helpful in the diagnosis and monitoring of GO therapy. To our knowledge, this is the first report of this kind presenting visual function restoration and structural recovery in a patient with advanced optic neuropathy in GO.

Macular blood flow changes in dysthyroid optic neuropathy after high-dose intravenous pulse methylprednisolone (IVMP)

OBJECTIVE

To investigate the changes in macular vessel density (VD) of the superficial layer of retina (SLR) and deep layer of retina (DLR) in dysthyroid optic neuropathy (DON) after high-dose intravenous pulse methylprednisolone (IVMP).

MATERIALS AND METHODS

Eighteen DON patients (29 eyes) who completed high-dose IVMP and 16 healthy individuals (32 eyes) were enrolled in this study. Optical coherence tomography angiography (OCTA) image analysis and comprehensive ophthalmic examinations were performed, including the SLR macular whole-image VD (SLR-mwiVD) and DLR-mwiVD, best-corrected visual acuity (BCVA), the mean deviation of visual field (VF-MD), pattern standard deviation of visual field (VF-PSD) and the other parameters.

RESULTS

The SLR-mwiVD (41.39 ± 4.71 vs. 48.13 ± 3.68, p < 0.001) and DLR-mwiVD (40.77 ± 5.85 vs. 49.14 ± 7.02, p < 0.001) were decreased in DON compared to control eyes. After IVMP, visual function parameters were improved, and SLR-mwiVD (49.41 ± 3.18, p < 0.001) and DLR-mwiVD (50.41 ± 4.04, p < 0.001) were increased in the DON group compared to pretreatment. The increased SLR-mwiVD and DLR-mwiVD were significantly correlated with improvements in BCVA (Log MAR: from 0.62 ± 0.49 to -0.01 ± 0.03, p < 0.001), VF-MD (from - 6.89 ± 2.89 dB to - 1.75 ± 1.29 dB, p < 0.001) and VF-PSD (from 4.38 ± 2.52 dB to 2.32 ± 1.64 dB, p < 0.001).

CONCLUSION

The increase in macular VD was significantly correlated with the improvement in visual function in DON after IVMP. Macular VD changes on OCTA may be a useful indicator for the response in DON after IVMP.

Outcomes of Patients With Dysthyroid Optic Neuropathy Treated With Intravenous Corticosteroids and/or Orbital Decompression Surgery: A Systematic Review and Meta-analysis

CONTEXT

The level of evidence is low for the treatment of patients with dysthyroid optic neuropathy (DON) and there is no consensus on the treatment of DON with intravenous high-dose glucocorticoids (ivGC) or direct surgical decompression.

OBJECTIVE

To compare the efficacy of glucocorticoid treatment and orbital decompression (OD) in DON.

DATA SOURCES

PubMed, EMBASE, and Cochrane Library were searched along with other sources.

STUDY SELECTION

A total of 17 studies met the inclusion criteria.

DATA EXTRACTION

Standard methodological guidance of the Cochrane Handbook was used and data were independently extracted by multiple observers. The primary outcomes were the improvement of best corrected visual acuity (ΔBCVA). Secondary outcomes were proptosis reduction, change in diplopia, visual field defects, and intraocular pressure (IOP).

DATA SYNTHESIS

The ΔBCVA in the ivGC + OD group was improved 0.26 LogMAR more than in the ivGC group (P = .007). The ΔBCVA in the OD group was better than in the ivGC group (P = .008). Posttreatment proptosis in the ivGC + OD and OD groups were improved further by 3.54 mm and 3.00 mm, respectively, than in the ivGC group (P < .01). The mean deviation (MD) in the ivGC + OD group was improved by an additional 5.33 dB than in the ivGC group (P = .002). The IOP in the ivGC + OD group was improved further than in the ivGC group (P = .03).

CONCLUSIONS

Based on the results of the present meta-analysis, OD or ivGC + OD may be more effective in improving BCVA and MD and reducing proptosis compared with ivGC. Compared with ivGC alone, ivGC + OD is more effective in improving IOP than ivGC. Although this study improves the hierarchy of evidence in the treatment of DON, additional randomized controlled trials are needed to confirm this conclusion.

Risk of Ocular Adverse Events With Taxane-Based Chemotherapy

Importance

Taxane-based chemotherapy agents, such as docetaxel and paclitaxel, are used for treating a wide range of cancers. Although much has been published on adverse events related to taxanes, data on ocular outcomes with these very important drugs are scant.

Objective

To quantify the risk of 3 mutually exclusive ocular adverse events of epiphora, cystoid macular edema (CME), and optic neuropathy with taxane-based chemotherapy agents by undertaking a large pharmacoepidemiologic study.

Design, Setting, and Participants

This retrospective cohort study design used a private health-claims database from the US that captures health information of more than 150 million enrollees. The study team created a cohort of new users of women with cancer who were taking taxane-based chemotherapy (docetaxel or paclitaxel) and new users of tamoxifen as controls. Study members were observed to the first incidence of each of the 3 mutually exclusive outcomes. An analysis of taxane-only users was also undertaken.

Exposure

Tamoxifen (unexposed) and taxanes (ie, paclitaxel and docetaxel) as the exposed.

Main Outcomes and Measures

First diagnosis of (1) epiphora, (2) cystoid macular edema (CME), or (3) optic neuropathy ascertained using International Statistical Classification of Diseases and Related Health Problems, Ninth Revision or International Statistical Classification of Diseases and Related Health Problems, Tenth Revision.

Results

Among the 18 219 users in the epiphora analysis and optic neuropathy analysis, there were 1824 taxane users (paclitaxel and docetaxel) (age, mean [SD], 62.1 [12.7] years) and 16 395 tamoxifen users (age, mean [SD], 54.6 [12.8] years), respectively. The crude hazard ratio (HR) for epiphora was 5.55 (95% CI, 2.99-10.29) and adjusted HR was 5.15 (95% CI, 2.79-9.54). For optic neuropathy, the crude HR was 4.43 (95% CI, 1.10-17.82) and the adjusted HR was 4.44 (95% CI, 1.04-18.87). Among the 18 433 users in the CME analysis, there were 1909 taxane users (paclitaxel and docetaxel) (age, mean [SD], 62.5 years) and 16 524 tamoxifen users (age, mean [SD], 54.6 years). The crude HR for CME comparing taxane users with tamoxifen users was 1.37 (95% CI, 0.72-2.60) and adjusted HR was 1.33 (95% CI, 0.70-2.53). The HRs for epiphora and CME in the taxane cohort during the time of exposure compared with the period prior to use of the drugs were 2.86 (95% CI, 1.11-7.39) and 2.27 (95% CI, 0.68-7.54), respectively.

Conclusions and Relevance

In a cohort of women who were using taxane chemotherapy agents, there was an association with elevated risk for epiphora, CME, and optic neuropathy. Ophthalmologists and oncologists should be aware of these adverse events in women with breast cancer who receive these drugs.

A Small Natural Molecule S3 Protects Retinal Ganglion Cells and Promotes Parkin-Mediated Mitophagy against Excitotoxicity

Glutamate excitotoxicity may contribute to retinal ganglion cell (RGC) degeneration in glaucoma and other optic neuropathies, leading to irreversible blindness. Growing evidence has linked impaired mitochondrial quality control with RGCs degeneration, while parkin, an E3 ubiquitin ligase, has proved to be protective and promotes mitophagy in RGCs against excitotoxicity. The purpose of this study was to explore whether a small molecule S3 could modulate parkin-mediated mitophagy and has therapeutic potential for RGCs. The results showed that as an inhibitor of deubiquitinase USP30, S3 protected cultured RGCs and improved mitochondrial health against NMDA-induced excitotoxicity. Administration of S3 promoted the parkin expression and its downstream mitophagy-related proteins in RGCs. An upregulated ubiquitination level of Mfn2 and protein level of OPA1 were also observed in S3-treated RGCs, while parkin knockdown resulted in a major loss of the protective effect of S3 on RGCs under excitotoxicity. These findings demonstrated that S3 promoted RGC survival mainly through enhancing parkin-mediated mitophagy against excitotoxicity. The neuroprotective value of S3 in glaucoma and other optic neuropathies deserves further investigation.

Erythropoietin in Optic Neuropathies: Current Future Strategies for Optic Nerve Protection and Repair

Erythropoietin (EPO) is known as a hormone for erythropoiesis in response to anemia and hypoxia. However, the effect of EPO is not only limited to hematopoietic tissue. Several studies have highlighted the neuroprotective function of EPO in extra-hematopoietic tissues, especially the retina. EPO could interact with its heterodimer receptor (EPOR/βcR) to exert its anti-apoptosis, anti-inflammation and anti-oxidation effects in preventing retinal ganglion cells death through different intracellular signaling pathways. In this review, we summarized the available pre-clinical studies of EPO in treating glaucomatous optic neuropathy, optic neuritis, non-arteritic anterior ischemic optic neuropathy and traumatic optic neuropathy. In addition, we explore the future strategies of EPO for optic nerve protection and repair, including advances in EPO derivates, and EPO deliveries. These strategies will lead to a new chapter in the treatment of optic neuropathy.

Advances in the Treatment of Thyroid Eye Disease Associated Extraocular Muscle Myopathy and Optic Neuropathy

PURPOSE OF REVIEW

To review emerging treatments for thyroid eye disease (TED) associated extraocular muscle myopathy and dysthyroid optic neuropathy (DON).

RECENT FINDINGS

Emerging targeted biologic therapies may alter the disease course in TED. Teprotumumab, a type I insulin-like growth factor receptor inhibitor, is the most recent addition to the treatments available for TED-associated extraocular muscle myopathy causing diplopia. Small studies also suggest a potential therapeutic benefit for DON. Various recent studies have also expanded our knowledge on conventional TED therapies. The therapeutic landscape of TED and its sequelae has evolved in recent years. New targeted therapies have the potential to reduce the extraocular muscle and orbital volume expansion which can lead to diplopia and vision loss from optic nerve compression. Longer term efficacy and durability data is needed to determine the role biologics, such as teprotumumab, should play in the treatment of TED patients compared to the current standard of care.

Rare early presentation of bilateral compressive optic neuropathy with complete vision loss from nasopharyngeal carcinoma

Nasopharyngeal carcinoma is very rarely associated with bilateral vision loss, and only in advanced disease. We report a case of bilateral severe compressive optic neuropathy as a first presentation from massive nasopharyngeal carcinoma with poor visual outcome despite corticosteroid, chemotherapy and radiotherapy. Red flag symptoms and signs of mass lesions in the posterior nasal space should be investigated and treated promptly to prevent devastating visual and prognostic consequences.

Visual loss and optic neuropathy in a patient with Klinefelter's syndrome, open-angle glaucoma, vitamin B12 (cobalamin) and folate deficiency

A 54-year-old man with Klinefelter's syndrome presented to the neuro-ophthalmology clinic with progressive painless visual blurring in the right eye over 2 years. He was receiving intramuscular testosterone therapy for hypogonadism and hypromellose for dry eye. Acuity was reduced bilaterally, and the right optic nerve head appeared pale and asymmetrically cupped. Optical coherence tomography revealed loss of retinal nerve fibre layer thickness in the right eye and visual field testing showed a developing right-ring scotoma. Blood tests showed vitamin B12 and folate deficiencies and polycythaemia. The patient was managed with intramuscular hydroxocobalamin, oral folate administration and re-initiation of his glaucoma medication. In Klinefelter's syndrome, signs of comorbid deficiency can be masked by the polycythaemic effect of testosterone therapy. For patients on long-term testosterone therapy, such as those with Klinefelter's syndrome, we recommend baseline ophthalmic examination and assessment, including intraocular pressure measurement, pachymetry, gonioscopy and screening 24-2 visual field testing.

Diversified Treatment Options of Adult Stem Cells for Optic Neuropathies

Optic neuropathies refer to a group of ocular disorders with abnormalities or dysfunction of the optic nerve, sharing a common pathophysiology of retinal ganglion cell (RGC) death and axonal loss. RGCs, as the retinal neurons in the central nervous system, show limited capacity in regeneration or recovery upon diseases or after injuries. Critically, there is still no effective clinical treatment to cure most types of optic neuropathies. Recently, stem cell therapy was proposed as a potential treatment strategy for optic neuropathies. Adult stem cells, including mesenchymal stem cells and hematopoietic stem cells, have been applied in clinical trials based on their neuroprotective properties. In this article, the applications of adult stem cells on different types of optic neuropathies and the related mechanisms will be reviewed. Research updates on the strategies to enhance the neuroprotective effects of human adult stem cells will be summarized. This review article aims to enlighten the research scientists on the diversified functions of adult stem cells and consideration of adult stem cells as a potential treatment for optic neuropathies in future clinical practices.

Therapeutic Options in Hereditary Optic Neuropathies

Options for the effective treatment of hereditary optic neuropathies have been a long time coming. The successful launch of the antioxidant idebenone for Leber's Hereditary Optic Neuropathy (LHON), followed by its introduction into clinical practice across Europe, was an important step forward. Nevertheless, other options, especially for a variety of mitochondrial optic neuropathies such as dominant optic atrophy (DOA), are needed, and a number of pharmaceutical agents, acting on different molecular pathways, are currently under development. These include gene therapy, which has reached Phase III development for LHON, but is expected to be  developed also for DOA, whilst most of the other agents (other antioxidants, anti-apoptotic drugs, activators of mitobiogenesis, etc.) are almost all at Phase II or at preclinical stage of research. Here, we review proposed target mechanisms, preclinical evidence, available clinical trials with primary endpoints and results, of a wide range of tested molecules, to give an overview of the field, also providing the landscape of future scenarios, including gene therapy, gene editing, and reproductive options to prevent transmission of mitochondrial DNA mutations.

A multi-center case series of sarcoid optic neuropathy

OBJECTIVE

The diagnosis of sarcoid optic neuropathy is time-sensitive, as delayed treatment risks irreversible vision loss. We sought to analyze its characteristics and outcomes.

METHODS

We performed a multi-center retrospective study of sarcoid optic neuropathy among 5 USA medical centers. Inclusion criteria were: 1) clinical optic neuropathy; 2) optic nerve/sheath enhancement on neuroimaging; 3) pathological confirmation of systemic or nervous system sarcoidosis.

RESULTS

Fifty-one patients were included. The median onset age of sarcoid optic neuropathy was 50 years (range, 17-70 years) and 71% were female. The median visual acuity at nadir in the most affected eye was 20/80 (range, 20/20 to no-light-perception). Thirty-four of 50 (68%) patients had radiologic evidence of other nervous system involvement and 20 (39%) patients had symptoms/signs of other cranial nerve dysfunction. Cerebrospinal fluid analysis revealed an elevated white blood cell count in 22 of 31 (71%) patients (median: 14/μL; range: 1-643/μL). Pathologic confirmation of sarcoidosis was by biopsy of systemic/pulmonary site, 34 (67%); optic nerve/sheath, 9 (18%); or other nervous system region, 8 (16%). Forty patients improved with treatment (78%), 98% receiving corticosteroids and 65% receiving steroid-sparing immunosuppressants, yet 11/46 patients (24%) had a visual acuity of 20/200 or worse at last follow-up.

CONCLUSIONS

Sarcoid optic neuropathy frequently occurs with other clinical and radiologic abnormalities caused by neurosarcoidosis and diagnostic confirmation occasionally requires optic nerve/sheath biopsy. Improvement with treatment is common but most patients have some residual visual disability. Improved recognition and a more expeditious diagnosis and treatment may spare patients from permanent vision loss.

Use of Rituximab After Orbital Decompression Surgery in Two Grave's Ophthalmopathy Patients Progressing to Optic Neuropathy

BACKGROUND

While orbital decompression can alleviate optic nerve compression and prevent further vision loss in dysthyroid optic neuropathy (DON), it cannot relieve inflammatory symptoms. Very high doses of intravenous glucocorticoids (GCs) are the first-line therapy for DON; however, the effective rate is only 40% and might be much lower in patients who fail high-dose GC pulse therapy and progressed to DON. The results of two case series studies indicated that rituximab treatment had a much better curative effect compared to very high doses of intravenous GCs, but some patients required urgent orbital decompression after rituximab injection because rituximab might lead to the release of cytokines, aggravated intraorbital edema, and further vision loss.

METHODS

We retrospectively studied the therapeutic process of two Grave's ophthalmopathy (GO) patients complicated with DON who failed high-dose GC pulse therapy and underwent orbital decompression. Both patients received single-dose (500 mg) rituximab treatment.

RESULTS

During more than 2 years of follow-up, rituximab treatment exhibited significant improvement in inflammatory symptoms, as manifested by a substantial decrease in Clinical Activity Score (CAS); meanwhile, the vision of both patients improved significantly and their diplopia was relieved.

CONCLUSIONS

The results of this study were consistent with those of two previous case series studies indicating the significant and lasting effect of rituximab treatment on DON, especially for patients with GC resistance or recurrence after GC therapy. Orbital decompression before rituximab treatment might reduce the incidence of rapid vision loss and urgent orbital decompression surgery caused by aggravated orbital edema after rituximab injection; however, the necessity for preventive decompression surgery requires further study.

[Guillain-Barré syndrome with refractory optic neuropathy]

A 60-year-old woman with a 3-day history of ataxic gait, blurred vision, and upper extremity paresthesia was admitted to our hospital. She presented with severe visual disturbances (finger counting), ophthalmoplegia, neck weakness, and sensory ataxia. Serum anti-GQ1b antibody, anti-GM3 antibody, and anti-GD3 antibody were strongly positive, which might contribute to the pathogenesis. Since we suspected Guillain-Barré syndrome (GBS), intravenous immunoglobulin therapy (IVIg) and high-dose steroid therapy were administered; however, improvements in her visual acuity were minimal. Additional IVIg and high-dose steroid therapy resulted in limited visual acuity improvements. Therapeutic strategies for patients with GBS and refractory optic neuropathy remain controversial.

Tocilizumab as first treatment option in optic neuropathy secondary to Graves' orbitopathy

Dysthyroid optic neuropathy (DON) is one of the complications that can affect Graves' orbitopathy (GO) patients. Its prevalence is estimated at less than 5%. It is usually treated with intravenous steroids, radiotherapy or orbital decompression. Tocilizumab has been proposed as a treatment option in cases of GO refractory to steroid treatment, with good clinical results. Our aim is to report the case of a patient with optic neuropathy secondary to GO treated with tocilizumab as primary treatment option.

Imaging Technologies for Assessing Neuroprotection in Glaucomatous Optic Neuropathy

The confocal scanning laser ophthalmoscope and the scanning laser polarimeter are two new imaging devices that may be beneficial in the diagnosis and monitoring of glaucoma patients. For each of these instruments, the authors describe benefits and limitations with regard to imaging mechanisms, sensitivity, and clinical applications. In comparison with currently used tests for glaucoma, these instruments provide quantitative assessment of the optic disc and RNFL at the clinic visit, with reduced need for pupil dilation and clear media. They also show promise for improving the ability to monitor progression of glaucomatous optic neuropathy and might allow better assessment of the efficacy of a neuroprotective agent.

Neuroprotection in Optic Neuropathy

Almost all optic neuropathies are untreatable, motivating the search for new therapies that address the final common pathway of optic nerve disease, retinal ganglion cell loss. These neuroprotective strategies have been primarily studied in glaucoma, the most common optic neuropathy, but increasing also tested at the laboratory and animal model level in nonglaucomatous optic neuropathies. More recently, several clinical trials, most of which are randomized, have begun to examine whether neuroprotection is efficacious in human optic nerve disease. Many of these trials are reviewed, along with the critical issues in the major areas of optic neuropathy, particularly the site of injury, the mechanism of axonal damage, and disease-specific features relevant to neuroprotection studies.

Steroid Treatment of Optic Neuropathies

The etiologies of optic neuropathy include inflammation, ischemia, toxic and metabolic injury, genetic disease, and trauma. There is little controversy over the practice of using steroids in the treatment of optic neuritis--it is well established that intravenous steroid treatment can speed visual recovery but does not alter final visual function. However, there is controversy surrounding the acceptable routes of administration, dosage, and course of treatment. Additionally, the typical patient with optic neuritis is young and otherwise healthy, and thus is likely to tolerate steroids well. In ischemic and traumatic causes of optic neuropathies, the initial injury is not inflammatory, but damage may be compounded by secondary injury due to resultant inflammation and swelling in the confined space of the optic canal. Steroids have been considered as a means of minimizing inflammation and swelling, and thus minimizing the secondary injury that results. However, the use of steroids in traumatic and ischemic optic neuropathies is highly controversial-the evidence for the efficacy of treatment with steroids is insufficient to show that there is significant benefit. Additionally, patients with these conditions are more likely to have comorbidities that make them vulnerable to significant adverse events with the use of steroids. In this article, we attempt to analyze the current state of the literature regarding the use of steroids in the treatment of optic neuropathies, specifically optic neuritis, nonarteritic anterior ischemic optic neuropathy, and traumatic optic neuropathy.

Atypical sarcoidosis-associated uveitis: diagnostic challenges

Sarcoidosis is a multisystem disease of unknown aetiology with pulmonary involvement in most patients. Uveitis is common and often characteristic. We report a case of ocular sarcoidosis with grossly atypical contiguous optic neuropathy and choroiditis and describe the diagnostic challenges in this highly unusual presentation. High-dose systemic corticosteroid and immunosuppressive treatment was required for sustained control of intraocular inflammation.

Bilateral Optic Neuropathy Associated with the Crest Variant of Scleroderma

We report a case of bilateral optic neuropathy associated with the CREST syndrome, a variant of scleroderma. Immunosuppressive therapy achieved significant improvement of the visual symptoms for two years. The pathophysiological mechanisms underlying this unique association remain unclear.

Influence of Nifedipine on the Visual Fields of Patients with Optic-Nerve-Head Diseases

Calcium-channel blockers have long been employed in coronary disease, and recent investigations have indicated their efficacy in improving the visual field in low-tension glaucoma or presumed vasospasm, possibly by enhancing ocular circulation. We evaluated the short-term influence of a typical calcium-channel blocker, nifedipine, on 59 patients with visual-field defects, some with optic-nerve-head pathology (n = 38) and some with normal-appearing optic nerve heads (n = 21). On the average, a statistically significant improvement of 1.2 dB was observed. Different types of patients, however, behaved quite differently. The younger the patient, the greater the improvement. Patients with normal optic nerve heads improved by 1.54 dB, whereas patients with optic-nerve-head excavation improved by only 0.66 dB. No response was observed in patients with anterior ischemic neuropathy. Marked deterioration was noted in one glaucoma patient with low systemic blood pressure. The visual-field changes were observed in the scotomatous and non-scotomatous areas. Thus, the calcium-channel blocker nifedipine can be effective in some selected diseases whose pathogenesis probably involves vascular dysregulation though it may even be contraindicated in others

IgG4-related cerebral pseudotumor with perineural spreading along branches of the trigeminal nerves causing compressive optic neuropathy: A case report

RATIONALE

Immunoglobulin G4-related disease (IgG4-RD) is characterized by tumor-like lesions, a dense lymphoplasmacytic infiltrate rich in IgG4-positive plasma cells, storiform fibrosis, and obliterative phlebitis. IgG4-RD has been described in a variety of organ systems; however, it rarely involves the central nervous system.

PATIENT CONCERNS

A 17-year-old woman visited our clinic with a complaint of blurred vision for the past 5 months. She also reported a painless right submandibular mass that had been present for 1 year. Her best-corrected visual acuity (BCVA) was 2.0 LogMAR, with an almost total visual field defect in the right eye.

DIAGNOSES

Magnetic resonance imaging (MRI) revealed lobulated parasellar tumors with perineural spreading along branches of the trigeminal nerves causing right optic nerve compression. A craniotomy with tumor removal and submandibular gland biopsy was performed. Histopathological analysis of the tumor revealed stromal fibrosis with atypical lymphoid infiltrations. Histopathological and immunohistochemical analysis of the submandibular gland confirmed the diagnosis of IgG4-RD.

INTERVENTIONS

The patient was administered 500mg/d of pulse methylprednisolone for 3 days, 500mg of intravenous rituximab every 2 weeks (for a total of 2 doses), and 500mg of intravenous pulse cyclophosphamide every month (for a total of 3 doses).

OUTCOMES

Two months after the initiation of immunosuppressive therapy, the patient's BCVA returned to 0.1 LogMAR with visual field defect recovery. The follow-up MRI showed the almost complete disappearance of the previously contrast-enhanced lesions.

LESSONS

Herein, we report a rare case of IgG4-RD presenting as a parasellar tumor and present a review of the related literature. Based on the case report, we propose that aggressive therapy with glucocorticoid, rituximab, and cyclophosphamide may potentially be useful for treating such cases.

The S1P1 receptor-selective agonist CYM-5442 protects retinal ganglion cells in endothelin-1 induced retinal ganglion cell loss

We investigated the feasibility and efficacy of using a specific sphingosine 1-phosphate (S1P1) receptor agonist, CYM-5442, to slow or block retinal ganglion cell (RGC) loss in endothelin-1 (ET-1) induced RGC loss. A single intravitreal injection of ET-1 (20pmol/ul), a potent vasoactive peptide that produces retinal vessels vasoconstriction, was used to induce and characterize RGC-specific cell death. CYM-5442 (1 mgr/kg) or vehicle was administered intraperitoneally for five consecutive days after ET-1-induced RGC loss. The functional extent of RGC loss injury was evaluated with pattern visual evoked potentials (VEP) and electroretinography. RGCs and retinal nerve fiber layer (RNFL) thickness were assessed in vivo using optical coherence tomography and ex vivo using Brn3a immunohistochemistry in flat-mounted retinas. ET-1 caused significant RGC loss and function loss one week after intravitreal injection. VEP showed preserved visual function after CYM-5442 administration compared to vehicle-treated animals (11.95 ± 0.86 μV vs 3.47 ± 1.20 μV, n = 12) (p < 0.05). RNFL was significantly thicker in the CYM treated-animals compared to the vehicle (93.62 ± 3.22 μm vs 77.72 ± 0.35 μm, n = 12) (p < 0.05). Furthermore, Brn3a immunohistochemistry validated this observation, showing significantly higher RGCs numbers in CYM treated rats than in the vehicle group (76,540 ± 303 vs 52,426 ± 1,932 cells/retina, n = 9) (p = 0.05). CYM-5442 administration was associated with significant retinal cleaved caspase-3 deactivation, indicating reduced apoptotic levels. The results of the present study further demonstrate the important role of S1P1 receptor agonists to lessen intravitreal ET-1 induced RGC loss.

The rare ethambutol-induced optic neuropathy: A case-report and literature review

RATIONALE

Ethambutol-induced optic neuropathy (EON) is a well-known complication that results from the use of ethambutol. The ocular manifestations of EON include painless loss of central vision and cecocentral scotomas in the visual field.

PATIENT CONCERNS

A 75-year-old Chinese Han man suffered from this rare ocular disorder because he took ethambutol for about 8 months.

DIAGNOSES

He was diagnosed as EON based on series of ophthalmic examinations performed.

INTERVENTIONS

Since he has stopped taking this drug for 3 months, we just offered some neurotrophic agents to him.

OUTCOMES

One month later, he came back for return visit. The ophthalmic examinations indicated recovery of the visual function very well.

LESSONS

The EON is a reversible optic neuropathy if the ocular toxicity is monitored closely among the tuberculosis patients that take ethambutol.

[Intracranial hypertension and jugular vein thrombosis]

BACKGROUND

Pseudotumor cerebri is an idiopathic increase in intracranial pressure, which commonly affects obese women of fertile age. The diagnostic criteria according to the guidelines of the German Society for Neurology are increased cerebrospinal fluid (CSF) pressure, symptoms of increased CSF pressure, normal results of CSF examination, no relevant medication and a lack of structural and vascular lesions in magnetic resonance imaging (MRI).

CASE REPORT

This article presents the case of a 39-year-old male patient who presented at hospital with visual obscuration and recently occurred double vision. Except for a recently diagnosed thrombosis of the left jugular vein of unknown origin, there was nothing else of note in the medical history. Biomicroscopic examination showed papilledema with hemorrhages and cotton wool spots. The CSF opening pressure was initially > 50 cmH2O. During therapy by lumbar puncture (three times), oral carbonic anhydrase inhibitors and loop diuretics, the abducens nerve palsy and papilledema receded. Anticoagulation therapy (initially with coumarin derivatives, then with low molecular weight heparins) was unsuccessful in eliminating the thrombosis of the jugular vein. Surgical intervention was not recommended by the vascular surgeons.

CONCLUSION

This case report demonstrates the unusual combination of (idiopathic) intracranial hypertension and thrombosis of the jugular vein, which occurred spontaneously and without any detectable coagulation disorders.

[Options for correction of endothelial dysfunction and oxidative stress in patients with primary open-angle glaucoma]

OBJECTIVE

To evaluate the efficacy of Tanakan in patients with primary open-angle glaucoma (POAG) with respect to its influence on vascular endothelial function and oxidative stress.

MATERIAL AND METHODS

Oxidative stress severity and antioxidant status were investigated in 52 patients with POAG divided into two groups. The effect of different treatment schemes on flow-dependent vasodilation and dynamic level of endotelin-1 (ET-1), which is a marker of endothelial dysfunction, was studied.

RESULTS

In the main group glaucomatous optic neuropathy progressed significantly as compared to the baseline (p<0.05). A trend for a decrease in malondialdehyde-modified low-density lipoproteins (MDA-LDL) and plasma malondialdehyde (MDA) levels (p<0.1) was also found, which indicates the activation of antioxidant response and resolution of oxidative stress. Due to endothelial dysfunction, plasma ET-1 levels in glaucoma patients are on average 5 times higher than the corresponding median physiological concentration. After the treatment started plasma ET-1 levels reduced and 3 months later approached the normal range. Reactive hyperemia testing and assessment of flow-dependent vasodilation revealed a poor initial endothelial response in 64.6% of patients. During the treatment paradoxical vasoconstriction was noted in 12.4% of patients. After the treatment patients from the main group demonstrated a statistically significant increase in brachial artery diameter.

CONCLUSION

Tanakan is showed to produce a positive effect on vascular remodeling in patients with POAG, which indicates its high antioxidant and antihypoxic activity. A significantly increased flow-dependent vasodilation found in the main group (especially 1-3 months after the beginning of the therapy) is thought to be due to an improved vasodilating ability of the vascular endothelium as the result of Tanakan use.

Artemin augments survival and axon regeneration in axotomized retinal ganglion cells

Artemin, a recently discovered member of the glial cell line-derived neurotrophic factor (GDNF) family, has neurotrophic effects on damaged neurons, including sympathetic neurons, dopamine neurons, and spiral ganglion neurons both in vivo and in vitro. However, its effects on retinal cells and its intracellular signaling remain relatively unexplored. During development, expression of GFRα3, a specific receptor for artemin, is strong in the immature retina and gradually decreases during maturation, suggesting a possible role in the formation of retinal connections. Optic nerve damage in mature rats causes levels of GFRα3 mRNA to increase tenfold in the retina within 3 days. GFRα3 mRNA levels continue to rise within the first week and then decline. Artemin, a specific ligand for GFRα3, has a neuroprotective effect on axotomized retinal ganglion cells (RGCs) in vivo and in vitro via activation of the extracellular signal-related kinase- and phosphoinositide 3-kinase-Akt signaling pathways. Artemin also has a substantial effect on axon regeneration in RGCs both in vivo and in vitro, whereas other GDNF family members do not. Therefore, artemin/GFRα3, but not other GDNF family members, may be of value for optic nerve regeneration in mature mammals.

A preliminary study of the neuroprotective role of citicoline eye drops in glaucomatous optic neuropathy

PURPOSE

To study the neuroprotective effect of topical citicoline.

MATERIALS AND METHODS

Experimental phase to evaluate the ability of citicoline eye drops to reach the vitreous and the retina: The right eyes of 5 mice CD1 were treated with two drops per day for three days of citicoline 1% and 2% (OMK1, Omikron Italia s.r.l.), and then the vitreous was analyzed with the liquid chromatography and spectrometry mass (LC-MS/MS). Clinical phase to determine if topical citicoline is able to delay glaucoma progression, considering perimetric parameters and electro functional tests. Patients were randomized in two groups, OMK1 and OAG. The first group was treated with OMK1 three times per day, plus hypotensive therapy for two months and one month of wash out. The second group was treated only with hypotensive treatment for three months.

RESULTS

LC-MS/MS detected the molecule very well, and only OMK1 showed systemic absorption. Thirty-four patients were enrolled, 16 in the OMK1 and 18 in the OAG group. Perimetric parameters showed a positive trend in individual eyes of patients in OMK1 group, but these values were not statistically significant in the whole group. Retinal ganglion cells function improved as shown by reduced P50 latency (P = 0.04) and increased P50-N95 amplitude (P < 0.0001) of pattern electroretinogram, up to 30 days after the washout (P = 0.01; P = 0.002). Visual evoked potential and retino-cortical time improvement regressed after 30 days of washout. In OAG group, there was any change during the follow-up. No adverse reactions were reported in both groups.

CONCLUSIONS

Topical citicoline seems to have a neuroprotective action.

The Heidelberg retina tomograph ancillary study to the European glaucoma prevention study: study design and baseline factors

PURPOSE

To describe the study design and baseline factors of the Heidelberg Retina Tomograph ancillary study within the EGPS. Furthermore, to examine the relationship between HRT optic disc topographic measurements and baseline demographic and ocular factors.

METHODS

Four hundred and eighty-nine ocular hypertensive participants were included. Each participant completed HRT imaging at least annually. The associations between HRT measurements and IOP, central corneal thickness (CCT), baseline photographic estimates of vertical CDR ratio (CDR), asymmetry between the two eyes in CDR ratio and baseline visual field indices were assessed using regression analysis.

RESULTS

Associations between HRT measurements and vertical CDR by photographs were found for almost all stereometric optic disc parameters in both univariate and multivariate analysis. The strongest association was found between vertical CDR measurements and disc, cup and rim area; cup and rim volume, CDR area, linear CDR, mean and maximum cup depth and cup shape measure (all p < 0.0001). In multivariate analysis, pattern standard deviation (PSD) and HRT disc area had significant associations with several HRT optic disc measurements. Furthermore, CCT was significantly associated with reference height and the glaucoma probability score (GPS, outside normal limits).

CONCLUSIONS

The EGPS is the first multicentre, placebo-controlled randomized clinical trial to use HRT for monitoring optic disc changes in participants with ocular hypertension. We found strong associations between stereophotographic vertical CDR estimates, HRT disc area, PSD and several HRT parameters. We found, furthermore, that the parameters reference height and GPS were significantly related to central corneal thickness.

[Acute optic neuropathy: differential diagnoses]

INTRODUCTION

Functional impairment of the optic nerve is characterized by visual loss, dyschromatopsia, visual field defects, relative afferent pupillary defect, and swelling or atrophy of the optic nerve.

AIM

To describe the spectrum of acute optic neuropathies, focusing on clinical features, diagnosis and treatment with an emphasis on pediatric entities.

DEVELOPMENT

Optic neuritis may be monophasic, recurrent, or part of a polysymptomatic demyelinating process. The aim of the treatment is to reduce number and severity of attacks and prevent future disability. Infectious neuritis is secondary to different microorganisms (bacteria, virus, fungi, or protozoa). Treatment is related to etiology. Nonarteritic ischemic optic neuropathy or idiopathic optic neuropathy is the most frequent form and is secondary to a disorder of small retinal vessels. Leber hereditary optic neuropathy is an important cause of chronic visual impairment and is characterized by selective involvement of the retinal ganglion cells. Until now, no curative treatment is available. Visual acuity is frequently conserved in papilledema associated with intracranial hypertension. The aim of treatment is to reduce intracranial hypertension and risk factors in case it is secondary.

CONCLUSIONS

Acute optic neuropathies are broad group of entities, of different etiologies, and with a variable visual prognosis. Findings of neurological examination, fundoscopy, and neuroimaging guide diagnosis and prompt treatment.

Comparison of adherence and persistence with bimatoprost 0.01% versus bimatoprost 0.03% topical ophthalmic solutions

OBJECTIVE

To compare patient adherence and persistence with bimatoprost 0.01%, a new formulation that offers equivalent intraocular pressure-lowering efficacy to bimatoprost 0.03% and improved tolerability, with that of the original bimatoprost 0.03% formulation.

METHODS

Pharmacy claims from a longitudinal database of prescription and medical claims for >115 million patients were analyzed. Patients with an initial (index) prescription for bimatoprost 0.01% or 0.03% between April and June 2011, and with no claim for ophthalmic prostaglandin or prostamide analogs during the preceding 18 months, were identified. Treatment adherence was expressed as the proportion of days covered (PDC) with study medication over the first 365 days after the index prescription. Treatment persistence over the first 12 months following the index prescription was assessed using Kaplan-Meier analyses, assuming a 30 day grace period for prescription refill. Treatment status (on/off study medication) was determined monthly for 12 months post-index.

RESULTS

In total, 6150 patients were assessed for treatment adherence and 7660 for persistence. Adherence was significantly better with bimatoprost 0.01% than bimatoprost 0.03% (mean PDC 0.540 vs. 0.438; p < 0.001). Significantly more patients had high adherence (PDC > 0.80) with bimatoprost 0.01% than 0.03% (29.1% vs. 17.3%; p < 0.001). Persistence was also significantly better with bimatoprost 0.01%, with 29.5% (95% confidence interval [CI]: 28.3%, 30.8%) versus 18.3% (95% CI: 16.8%, 19.9%) of patients remaining on continuous treatment for 12 months (p < 0.001). At 12 months, significantly more patients were 'on treatment' (continuing/restarting treatment) with bimatoprost 0.01% than 0.03% (48.8% vs. 33.9%; p < 0.001). Sensitivity analyses demonstrated similar findings in cohorts of ocular hypotensive treatment-naïve and elderly (≥65 years) patients.

CONCLUSIONS

Bimatoprost 0.01% offers adherence and persistency advantages over bimatoprost 0.03% in patients requiring ocular hypotensive therapy. Study limitations included the observational design, lack of control for imbalances in patient characteristics, and assumption that prescription refill is synonymous with medication use.

An adherence based cost-consequence model comparing bimatoprost 0.01% to bimatoprost 0.03%

OBJECTIVES

Estimate the long-term direct medical costs and clinical consequences of improved adherence with bimatoprost 0.01% compared to bimatoprost 0.03% in the treatment of glaucoma.

METHODS

A cost-consequence model was constructed from the perspective of a US healthcare payer. The model structure included three adherence levels (high, moderate, low) and four mean deviation (MD) defined health states (mild, moderate, severe glaucoma, blindness) for each adherence level. Clinical efficacy in terms of IOP reduction was obtained from the randomized controlled trial comparing bimatoprost 0.01% with bimatoprost 0.03%. Medication adherence was based on observed 12 month rates from an analysis of a nationally representative pharmacy claims database. Patients with high, moderate and low adherence were assumed to receive 100%, 50% and 0% of the IOP reduction observed in the clinical trial, respectively. Each 1 mmHg reduction in IOP was assumed to result in a 10% reduction in the risk of glaucoma progression. Worse glaucoma severity health states were associated with higher medical resource costs. Outcome measures were total costs, proportion of patients who progress and who become blind, and years of blindness. Deterministic sensitivity analyses were performed on uncertain model parameters.

RESULTS

The percentage of patients progressing, becoming blind, and the time spent blind slightly favored bimatoprost 0.01%. Improved adherence with bimatoprost 0.01% led to higher costs in the first 2 years; however, starting in year 3 bimatoprost 0.01% became less costly compared to bimatoprost 0.03% with a total reduction in costs reaching US$3433 over a lifetime time horizon. Deterministic sensitivity analyses demonstrated that results were robust, with the majority of analyses favoring bimatoprost 0.01%. Application of 1 year adherence and efficacy over the long term are limitations.

CONCLUSIONS

Modeling the effect of greater medication adherence with bimatoprost 0.01% compared with bimatoprost 0.03% suggests that differences may result in improved economic and patient outcomes.

The rate of structural change: the confocal scanning laser ophthalmoscopy ancillary study to the ocular hypertension treatment study

PURPOSE

To compare rates of topographic change in ocular hypertensive eyes that develop primary open-angle glaucoma (POAG) compared to eyes that do not, and to identify factors that influence the rate of change.

DESIGN

Longitudinal, randomized clinical trial.

METHODS

Four hundred forty-one participants (832 eyes) in the Confocal Scanning Laser Ophthalmoscopy Ancillary Study to the Ocular Hypertension Treatment Study were included. POAG was defined as repeatable visual field, photography-based optic disc changes, or both. The rate of topographic change in the 52 participants (66 eyes) who developed POAG was compared with that of participants who did not develop POAG using multivariable mixed effects models.

RESULTS

In both univariate and multivariate analyses, the rate of rim area loss was significantly faster in eyes in which POAG developed than in eyes in which it did not (univariate mean, -0.0131 mm(2)/year and -0.0026 mm(2)/year, respectively). The significantly faster rate of rim area loss in black persons found in the univariate analysis did not remain significant when baseline disc area was included in the model. In multivariate analyses, the rate of rim area loss and other topographic parameters also was significantly faster in eyes with worse baseline visual field pattern standard deviation and higher intraocular pressure during follow-up. Moreover, a significant rate of rim area loss was detected in eyes in which POAG did not develop (P < .0001). The rate of rim area loss in eyes with an optic disc POAG endpoint was significantly faster than in those with a visual field POAG endpoint.

CONCLUSIONS

The rate of rim area loss is approximately 5 times faster in eyes in which POAG developed compared with eyes in which it did not. These results suggest that measuring the rate of structural change can provide important information for the clinical management of ocular hypertensive patients. Additional follow-up is needed to determine whether the statistically significant change in the eyes in which POAG did not develop represents normal aging or glaucomatous change not detected by conventional methods.

Preliminary study on combined pharmacological and laser treatment in optic pit serous maculopathy after literature review

The pit of the optic nerve head (ON) is a rare congenital defect that sometimes presents itself with a maculopathy of various neuroretinal layers for unknown reason. This study was focused, before and after pharmacological and parasurgical treatment, on the structural and functional visual assessment in a patient with optic pit maculopathy (OPM). In order to achieve this the latest generation of hi-tech diagnostic tests were used, such as Spectral-Domain Optical Coherence Tomography (SD-OCT), Visual Evoked Potentials (VEP), full-field Electroretinography (ERG), multifocal ERG (mfERG), Microperimetry (MP-1), Standard Automated Perimetry (SAP), Fluorescein Angiography (FA) and Indocyanine Green Angiography (ICG). The research was conducted through a review of past and recent literature.

Painful ophthalmoplegia with simultaneous orbital myositis, optic and oculomotor nerve inflammation and trigeminal nucleus involvement in a patient with herpes zoster ophthalmicus

Viral infection is a rare cause of painful ophthalmoplegia. We report on a 67-year-old patient who developed painful double vision after a vesicular skin rash on the left forehead. MRI disclosed simultaneous inflammatory lesions in all extraocular muscles, the second and third cranial nerve, as well as pathological signal intensity along the spinal trigeminal tract and nucleus within the medulla oblongata and the pons. Cerebrospinal fluid and serum tests for varicella zoster were positive. The patient was treated effectively with intravenous acyclovir and methylprednisolone. Simultaneous lesions in various neighbouring neural structures may be characteristic for the highly neurotropic behaviour of the herpesviridae and should be considered as a cause of painful ophthalmoplegia that can be depicted by appropriate imaging.

Medial transconjunctival intrinsic optic nerve biopsy: surgical technique and indications

AIM

To describe a method of intrinsic optic nerve biopsy and its indications.

METHODS

Retrospective case series.

RESULTS

We report four cases that required intrinsic optic nerve biopsy for progressive optic neuropathy with uncertain diagnosis after negative systemic investigations. In all cases, a medial transconjunctival approach was used. There were no complications noted with this technique in the series, specifically there was no reported deterioration in vision. One case of neurosarcoidosis was confirmed. In the other three cases, the pathology results were non-diagnostic but ruled out serious causes such as central nervous system leukaemia relapse.

CONCLUSION

Medial transconjunctival intrinsic optic nerve biopsy is a minimally invasive and safe technique. The technique is suitable for sampling pathology in the distal portion of the optic nerve. Optic nerve biopsy is indicated when there is significant loss of vision from an isolated optic nerve disease and all systemic investigations have failed to identify the cause, or where the clinical course of a presumed diagnosis is atypical.

Toxic optic neuropathy

Toxic optic neuropathy (TON) is a disease entity which is not only underdiagnosed, but also often diagnosed at a stage when recovery of vision is not possible. This article gives an overview of common causes, clinical features, and management of TON.

In the eye of the Cuban epidemic neuropathy storm: Rosaralis Santiesteban MD PhD, Neurology and Neurosurgery Institute. Interview by Christina Mills

When Cuba was hit by a neuropathy epidemic two decades ago, Dr Rosaralis Santiesteban was one of the Cuban health professionals who played a key role in its management, as reflected in a recent issue of Seminars in Ophthalmology. She was well prepared for her part: trained in medicine at the University of Havana before completing a residency in ophthalmology and eventually a doctorate in medical sciences, she has received multiple honors for her research, publishing and teaching. In 2007, she was named Distinguished Researcher by the Cuban Ministry of Science, Technology and the Environment. She has headed the Department of Neuro-ophthalmology at Cuba's Neurology and Neurosurgery Institute since 1977. Now called Cuban Epidemic Neuropathy, the 1990s epidemic that affected over 50,000 Cubans is the largest and best-documented of its kind in history. As researchers pressed to unravel the mystery of its etiology to hasten the epidemic's end, Dr Santiesteban recognized that similar outbreaks had occurred during Cuba's wars of independence in the late 1800s--described in her book, Epidemias y Endemias de neuropatía en Cuba. In the proverbial eye of the storm during the 1990s epidemic, she shares her reflections below on the context, causes, evolution and lessons learned from the challenge that put Cuba's health system to the test.

Primary Wegener's granulomatosis of the orbital apex with initial optic nerve infiltration

Wegener's granulomatosis can involve the orbit and sometimes the optic nerve. This usually occurs as a result of contiguous spread from affected sinuses or extraocular muscles, or from a vasculitic posterior optic neuropathy. However, we present an unusual case of isolated orbital apex infiltrative disease in a patient with known Wegener's granulomatosis. This initially caused painless optic neuropathy and progressed to painful ophthalmoplegia and blindness. Optic nerve biopsy, performed to exclude methotrexate-induced lymphoma, confirmed optic nerve infiltration. The condition was refractory to high-dose pulsed methylprednisolone but the patient gained symptomatic relief from rituximab. Wegener's granulomatosis should be considered in cases of isolated posterior optic neuropathy, and close attention should be placed on imaging the orbital apex.

Optic neuropathy in methylmalonic acidemia: the role of neuroprotection

We report the case of a patient with an optic neuropathy induced by neurotoxicity in the setting of methylmalonic acidemia. The patient responded with a significant and long-term improvement in visual acuity, perimetry, and chromatic function after a neuroprotective treatment with vitamin E and coenzyme Q10 was started. Coenzyme Q10 levels had been proven to be normal before starting treatment. This case report is particularly important because it describes a possible treatment for optic neuropathy in methylmalonic patients. Although the response might be, in part, specific to the individual, it suggests the existence of a cause-effect relationship between the treatment undergone by our patient and the improvement in her visual acuity. To date, no other treatments with beneficial effects have been reported for the few optic neuropathies caused by methylmalonic acidemia. Further studies should determine the applicability of coenzyme Q10 and vitamin E for the treatment of optic neuropathies in methylmalonic acidemia.