Upper Limit of Retinal Nerve Fibre Layer Thickness in Patients with Pseudopapilloedema.

An initial misdiagnosis of papilloedema in a patient with optic nerve head swelling can be anxiety-provoking and may result in unnecessary, invasive, and costly tests. Cirrus high definition, spectral domain-optical coherence tomography (Cirrus HD-OCT) may provide a rapid and non-invasive test. We sought to determine an upper limit of average retinal nerve fibre layer (RNFL) thickness in patients with pseudopapilloedema without visible drusen using Cirrus HD-OCT that could be utilised in conjunction with the clinical presentation and physical examination when managing patients with optic nerve head swelling. Inclusion criteria consisted of at least two neuro-ophthalmological visits and repeated imaging of the optic nerve head with Cirrus HD-OCT at least 6 months apart. Exclusion criteria included clinically visible drusen along with previous or concomitant diagnosis of retinal or other optic nerve pathology. Thirty-eight eyes from 19 patients with pseudopapilloedema were included in this study. The upper limit of average RNFL thickness was defined as two standard deviations above the mean of the average RNFL thickness and was calculated to be 158.65 µm for scans obtained with Cirrus HD-OCT devices. A patient with suspected optic nerve head swelling, an average RNFL thickness less than 158.65 µm, and no other evidence of papilloedema or neurological signs or symptoms can be managed with serial follow-ups with OCT imaging for at least 6 months. If the patient continues to have no clinical symptoms suggesting increased intracranial pressure and the average RNFL thickness is stable, the likelihood of papilloedema is minimal.

Lemierre syndrome associated mycotic cavernous sinus thrombosis and carotid aneurysm after COVID-19.

Purpose: The purpose of this article is to report a case of Lemierre syndrome associated mycotic aneurysm of the intracavernous carotid artery leading to cavernous sinus syndrome in an otherwise healthy, young man in the setting of COVID-19 infection. Observations: An 18-year-old, otherwise healthy male athlete developed fever, chills, and headache and was found to be positive for COVID-19 with gram negative bacteremia. While on systemic antibiotic treatment, he developed acute, left-sided, 6th nerve palsy and was found to have bacterial sinusitis, left-sided intracavernous mycotic aneurysm, and cavernous sinus thrombosis on imaging studies. Despite systemic antibiotic and antiplatelet therapy, he developed progressively worsening left-sided ophthalmoplegia and vision decline. He subsequently underwent left internal carotid artery embolization and cervical internal carotid artery sacrifice with excellent outcome. Conclusion and importance: Lemierre syndrome can have atypical presentations and complications, including cavernous sinus thrombosis and mycotic aneurysms. Recognition of signs and symptoms, including progressive multiple cranial neuropathies, can aid in early diagnosis and management, which requires multidisciplinary care tailored to each individual based on risk of intervention.

Vitreoretinal Findings in Nonarteritic Ischemic Optic Neuropathy.

BACKGROUND: Although nonarteritic anterior ischemic optic neuropathy (NAION) is considered a disorder that primarily affects the optic nerve head, optical coherence tomography (OCT) shows peripapillary and foveal subretinal fluid associated with optic disc swelling from NAION. We sought to further evaluate retinal and vitreous changes in patients with NAION. METHODS: Patients diagnosed with NAION at the New England Eye Center between 2013 and 2017 were evaluated using OCT. The presence and distribution of subretinal fluid was analyzed. Evidence of other vitreoretinal changes, including vitreopapillary traction (VPT) and the presence of hyperreflective dots (HRD), were also determined. RESULTS: Twenty-five eyes from 20 patients who presented within 4 weeks of symptom onset were assessed. Peripapillary subretinal fluid was seen in 16 eyes (64%). Of those eyes, the subretinal fluid extended into the macula in 4 eyes (16%). Visual acuity improved in 2 of 4 eyes after subfoveal fluid resolution. Intraretinal cysts located in the peripapillary region were seen in 8 eyes (32%), HRD were noted in 11 (44.0%). There was no evidence of VPT. CONCLUSIONS: A substantial number of patients with NAION have subretinal fluid on OCT, consistent with prior reports. Resolution of subfoveal fluid may result in some recovery of visual acuity. Other retinal changes, such as intraretinal cysts and HRD, are present but have unclear implications. We did not find evidence of a primary role of VPT in the pathophysiology of NAION.

BILATERAL EPIRETINAL MEMBRANE FORMATION AFTER INTRAVITREAL INJECTIONS OF AUTOLOGOUS MESENCHYMAL STEM CELLS.

PURPOSE: The authors describe a case of new bilateral epiretinal membranes and vitreous cells after intravitreal and sub-Tenon's injections of bone marrow-derived stem cells. METHODS: A case report of a 43-year-old man with OPA-1 autosomal dominant optic atrophy who self-enrolled in a stem cell therapy clinical trial and received simultaneous bilateral intravitreal and sub-Tenon's injections of bone marrow-derived stem cells. RESULTS: Within one month of receiving the injections, the patient developed epiretinal membranes and vitreous cells in both eyes, seen with optical coherence tomography. CONCLUSION: Stem cell therapy has been gaining popularity as a potential intervention for progressive retinal and optic nerve diseases; however, the mechanism of action of bone marrow-derived stem cells is still not well understood and may result in unintended cell differentiation.

Prepapillary vascular loop-a new classification.

BACKGROUND/OBJECTIVES: To analyze the ophthalmic characteristics of congenital prepapillary vascular loop (PVL) and to propose a new morphologic classification dividing the loops into six types. SUBJECTS/METHODS: Collaborative multinational multicentre retrospective study of PVL cases. RESULTS: There was a total of 49 cases (61 eyes), 37 unilateral (75.5%) and 12 bilateral (24.5%), 32 arterial type (65.3%) and 18 venous type (36.7%) (one patient had either kind in each eye). The mean number of loops per eye was 2.7 (range, 1-7). The loops were asymptomatic in 42 cases (85.7%). Other findings included: the presence of cilioretinal artery (14 cases), retinal vascular tortuosity (26 cases), amaurosis fugax (1 case), branch retinal artery occlusion (1 case) and vitreous haemorrhage (3 cases). Six morphologic loop types could be discerned based on elevation (flat vs. elevated), shape (figure of 8 or corkscrew with hyaline sheath), number (multiple or single), location (central or peripheral), lumen size (arterial vs. arteriolar) and presence of vascular tortuosity or vitreous traction. CONCLUSIONS: PVL are usually asymptomatic and can be divided into six morphologic types with different pathogenesis during early embryogenesis.

Ganglion Cell Complex Analysis as a Potential Indicator of Early Neuronal Loss in Idiopathic Intracranial Hypertension.

Reliable visual field testing is the gold standard in identifying future vision loss in patients with Idiopathic Intracranial hypertension (IIH). However, when field performance is unreliable, GCC analysis may be useful. We evaluated IIH patients over three visits: initial visit, follow-up visit and a third visit, almost 1 year later. We evaluated mean deviation (MD), GCC and RNFL at presentation and the second visit and compared it to the mean deviation (MD) on fields at the third visit. As early as the second visit, GCC loss correlated with visual field results seen at the third visit.

IMMUNE RECONSTITUTION INFLAMMATORY SYNDROME CAUSING PROGRESSIVE OPTIC NERVE EDEMA IN CRYPTOCOCCAL MENINGITIS.

PURPOSE: To report an human immunodeficiency virus-positive patient undergoing therapy for cryptococcal meningitis who developed progressive optic disk edema that was steroid responsive. METHODS: Observational case report. RESULTS: One month after commencing antifungal treatment for cryptococcal meningitis, the patient developed bilateral, progressive, recurrent optic disk edema with subretinal fluid that coincided with initiation of highly active antiretroviral therapy and recovery of CD4 cell counts. Lumbar puncture revealed normal opening pressure, and cerebrospinal fluid showed no recurrence of cryptococcal infection. There was no evidence of uveitis. The patient rapidly improved with a 5-day course of high-dose intravenous methylprednisolone. CONCLUSION: Recurrent optic disk edema with loss of vision after treatment of cryptococcal meningitis in the setting of normal intracranial pressure may represent a unique manifestation of immune reconstitution inflammatory syndrome localized to the optic nerve without uveitis. This is consistent with the temporal relationship between starting highly active antiretroviral therapy, CD4 count recovery, and the development of progressive disk edema in the study patient. Isolated optic nerve inflammation as a manifestation of immune reconstitution inflammatory syndrome has not been widely reported.

Retrospective, Multicenter Comparison of the Clinical Presentation of Patients Presenting With Diplopia From Giant Cell Arteritis vs Other Causes.

BACKGROUND: Although giant cell arteritis (GCA) is a well-known cause of transient and permanent vision loss, diplopia as a presenting symptom of this condition is uncommon. We compared symptoms and signs of patients presenting with diplopia from GCA to those from other causes. METHODS: This was a multicenter, retrospective study comparing the clinical characteristics of patients presenting with diplopia from GCA with age-matched controls. Demographic information, review of symptoms, ophthalmic examination, and laboratory data of biopsy-proven patients with GCA were compared with those of age-matched controls presenting with diplopia. RESULTS: A total of 27 patients presented with diplopia from GCA, 19 with constant diplopia, and 8 with transient diplopia. All patients with constant diplopia from GCA were matched with 67 control subjects who had diplopia from other etiologies. Patients with GCA were more likely to describe other accompanying visual symptoms (58% vs 25%, P = 0.008), a greater number of systemic GCA symptoms (3.5, GCA vs 0.6, controls, P < 0.001) such as headache (94% [17/18] vs 39% [23/67]; P < 0.001), jaw claudication (80% [12/15] vs 0% [0/36]; P < 0.001), and scalp tenderness (44% [7/16] vs 7% [3/43]; P < 0.001). Ocular ischemic lesions (26% vs 1%, P < 0.001) were also common in patients with diplopia from GCA. Inflammatory markers were elevated significantly in patients with GCA vs controls (erythrocyte sedimentation rate: 91% [10/11] vs 12% [3/25], P < 0.001; C-reactive protein: 89% [8/9] vs 11% [2/19], P < 0.001). CONCLUSIONS: GCA is a rare but serious cause of diplopia among older adults and must be differentiated from other more common benign etiologies. Our study suggests that most patients with diplopia from GCA have concerning systemic symptoms and/or elevated inflammatory markers that should trigger further work-up. Moreover, careful ophthalmoscopic examination should be performed to look for presence of ocular ischemic lesions in older patients presenting with acute diplopia.

REVERSIBLE NYCTALOPIA ASSOCIATED WITH VITAMIN A DEFICIENCY AFTER RESECTED MALIGNANT ILEAL CARCINOID AND PANCREATIC ADENOCARCINOMA.

PURPOSE: To describe the rapid time course of visual and electroretinographic recovery from vitamin A deficiency in a patient with a history of multiple resected abdominal tumors, including ileal carcinoid and pancreatic adenocarcinoma. METHODS: A 61-year-old white man with a history of resected malignant ileal carcinoid and Stage III pancreatic adenocarcinoma referred with complaints of 6 weeks of difficulty with night vision. RESULTS: Initial testing showed significantly reduced scotopic rod responses in both eyes and decreased vitamin A levels and a normal cancer-associated retinopathy laboratory panel. He had complete recovery of both his symptoms and full-field electroretinography within 5 days of starting intramuscular vitamin A. CONCLUSION: Vitamin A deficiency-related retinopathy after abdominal surgery may be an underreported complication. This case provides a unique clinical perspective in our patient with a history of ileal carcinoid and Stage III pancreatic adenocarcinoma and confirms that rapid symptomatic and electroretinographic recovery is possible with appropriate treatment.

Optical coherence tomography findings in methanol toxicity.

BACKGROUND: Methanol toxicity poses a significant public health problem in developing countries, and in Southeast Asia, where the most common source of poisoning is via adulterated liquor in local drinks. Methanol toxicity can have devastating visual consequences and retinal specialists should be aware of the features of this toxic optic neuropathy. The authors report a case of severe systemic methanol toxicity and relatively mild optic neuropathy demonstrating unique retinal changes on optical coherence tomography (OCT). CASE PRESENTATION: A previously healthy student developed ataxia, difficulty breathing and loss of consciousness hours after drinking homemade alcohol while traveling in Indonesia. She was found to have a serum pH of 6.79 and elevated methanol levels. She was treated with intravenous ethanol, methylprednisolone and sodium bicarbonate. When she awoke she had bilateral central scotomas. At presentation, she had central depression on visual field testing. OCT of the retinal nerve fiber layer (RNFL) was normal but ganglion cell layer analysis (GCL) showed highly selective loss of the nasal fibers in both eyes. Further, OCT of the macula demonstrated inner nuclear layer (INL) microcysts in the corresponding area of selective GCL loss in both eyes. CONCLUSIONS: The selective involvement of the papillomacular bundle fibers is common in toxic optic neuropathies and represents damage to the small caliber axons rich in mitochondria. Despite severe systemic toxicity, the relative sparing of the optic nerve in this case enabled characterization of the evolution of methanol toxicity with segmental GCL involvement and preservation of the RNFL, corresponding to the papillomacular bundle. This is the first reported case of INL microcysts in methanol optic neuropathy and supports that they are a non-specific finding, and may represent preferential damage to the papillomacular bundle.

Characterization of Charcot-Marie-Tooth optic neuropathy.

Varying degrees of optic neuropathy can be seen in patients with Charcot-Marie-Tooth (CMT) disease. To define and characterize the extent of optic neuropathy in patients with CMT2A and CMT1A, two patients from both sub-classifications were evaluated. All patients underwent complete neuro-ophthalmic examinations, and optical coherence (OCT) measurements of the retinal nerve fiber layer (RNFL) and ganglion cell layer complex (GCC) were obtained, along with pattern visual evoked potential (VEP) and pattern electroretinogram (ERG) recordings. RNFL thickness measurements were decreased in both patients with CMT2A, and normal in both patients with CMT1A. GCC measurements were decreased in both patients with CMT2A, mildly decreased in one patient with CMT1A and normal in the second CMT1A patient. VEP latencies were delayed in one patient with CMT2A and one patient with CMT1A. VEP latencies were immeasurable in the other CMT2A patient and not obtained in the second CMT1A patient. Pattern ERG P50-N95 amplitudes were decreased in both patients with CMT2A and normal in one patient with CMT1A. The pattern ERG was immeasurable in the second patient with CMT1A. The pattern of RNFL and GCC thinning in CMT2A with optic neuropathy, a subset of HMSN VI, closely resembles that seen in other mitochondrial optic neuropathies.

Ganglion cell layer complex measurements in compressive optic neuropathy.

PURPOSE OF REVIEW: Neuroophthalmologists and neurosurgeons are often asked by their patients what their visual prognosis will be after decompression of an optic chiasm lesion. Previous methods have been studied but have not provided consistent guidance. However, a recent algorithm which allows for retinal ganglion cell analysis from optical coherence tomography (OCT) may be more helpful. RECENT FINDINGS: Recent studies have shown that ganglion cell layer complex (GCC) measurements from OCT strongly correlate with the visual field loss associated with compressive optic neuropathies. For example, GCC measurements show corresponding binasal thinning with bitemporal hemianopia. Some investigators have also shown that more preserved GCC thickness is preoperatively associated with better postsurgical outcome. Interestingly, some patients experience almost complete recovery of visual fields despite considerable GCC thinning, and others may have GCC loss before they develop demonstrable visual field defects. SUMMARY: GCC measurements on OCT strongly correlate with visual field defects from optic chiasm compressive lesions and may help with regard to prognosis following treatment. However, considerable visual recovery is possible despite persistent GCC loss.

Pathological Confirmation of Optic Neuropathy in Familial Dysautonomia.

Clinical data suggest that optic neuropathy and retinal ganglion cell loss are the main cause of visual decline in patients with familial dysautonomia, but this has not previously been confirmed by pathological analyses. We studied retinas and optic nerves in 6 eyes from 3 affected patients obtained at autopsy. Analyses included routine neurohistology and immunohistochemistry for neurofilaments, cytochrome c oxidase (COX), and melanopsin-containing ganglion cells. We observed profound axon loss in the temporal portions of optic nerves with relative preservation in the nasal portions; this correlated with clinical and optical coherence tomography findings in 1 patient. Retinal ganglion cell layers were markedly reduced in the central retina, whereas melanopsin-containing ganglion cells were relatively spared. COX staining was reduced in the temporal portions of the optic nerve indicating reduced mitochondrial density. Axonal swelling with degenerating lysosomes and mitochondria were observed by electron microscopy. These findings support the concept that there is a specific optic neuropathy and retinopathy in patients with familial dysautonomia similar to that seen in other optic neuropathies with mitochondrial dysfunction. This raises the possibility that defective expression of the IkB kinase complex-associated protein (IKAP) resulting from mutations in IKBKAP affects mitochondrial function in the metabolism-dependent retinal parvocellular ganglion cells in this condition.

Optical Coherence Tomography Angiography in Nonarteritic Anterior Ischemic Optic Neuropathy.

BACKGROUND: Optical coherence tomography angiography (OCTA) has demonstrated good utility in qualitative analysis of retinal and choroidal vasculature and therefore may be relevant in the diagnostic and treatment efforts surrounding nonarteritic anterior ischemic optic neuropathy (NAION). METHODS: Retrospective, cross-sectional study of 10 eyes of 9 patients with a previous or new diagnosis of NAION that received imaging with OCTA between November 2015 and February 2016. Two independent readers qualitatively analyzed the retinal peripapillary capillaries (RPC) and peripapillary choriocapillaris (PCC) for flow impairment. Findings were compared with automated visual field and structural optical coherence tomography (OCT) studies. RESULTS: Flow impairment seen on OCTA in the RPC corresponded to structural OCT deficits of the retinal nerve fiber layer (RNFL) and ganglion cell layer complex (GCC) in 80% and 100% of eyes, respectively, and to automated visual field deficits in 90% of eyes. Flow impairment seen on OCTA in the PCC corresponded to structural OCT deficits of the RNFL and GCC in 70% and 80% of eyes, respectively, and to visual field deficits in 60%-80% of eyes. CONCLUSIONS: OCTA can noninvasively visualize microvascular flow impairment in patients with NAION.