1/375. carbon monoxide poisoning causes optic neuropathy.PURPOSE: To describe the electrophysiological and psychophysical effects of carbon monoxide (CO) poisoning on visual function. methods: Three patients are presented who suffered CO poisoning, two due to suicide attempts and one in the course of a road traffic accident. After a full ocular examination, Goldmann visual fields, flash and pattern visual evoked potentials (VEPs) and flash and pattern electroretinograms (ERGs) were tested. RESULTS: electrophysiology showed reduced or absent N95 components of the pattern ERG and delayed, reduced VEPs. A positive-negative-positive (PNP) VEP waveform was seen in two cases. In one case, where presentation occurred at an early stage, visual and electrophysiological function was improved with hydroxycobalamine. CONCLUSIONS: The combination of ERG and VEP findings suggest that CO poisoning can cause a toxic optic neuropathy that may have a similar aetiological mechanism to that in tobacco amblyopia. Early treatment with hydroxycobalamine may be of some benefit.- - - - - - - - - - ranking = 1keywords = ocular (Clic here for more details about this article) |
2/375. Optic nerve cysticercosis in the optic canal.The authors present a first case of cysticercosis in the optic canal in a fifteen-year-old female patient. cysticercosis of the optic nerve is rare. A cyst in the optic canal, beneath the sheath of the optic nerve, has never been reported. The patient presented with rapidly diminishing vision in the left eye, headache and papillitis. A magnetic resonance imaging revealed a cystic lesion at the entrance of the optic canal. Surgery performed was a transcranial orbitotomy which included deroofing of the optic canal and removal of the cyst from under the sheath of the optic nerve. The cyst proved to be cysticercus histopathologically. The outcome was a remarkable visual recovery.- - - - - - - - - - ranking = 1.1081233817966keywords = eye (Clic here for more details about this article) |
3/375. Cerebral metastasis presenting with altitudinal field defect.A 75-year-old man presented with a unilateral inferior altitudinal visual field defect and a history of weight loss and night sweats. The acuity in the affected eye was 20/200, otherwise his ocular examination was normal. neuroimaging demonstrated a post-fixed chiasm, with a frontal metastasis compressing the intracerebral portion of the optic nerve. A chest x-ray showed classical cannon ball lesions, secondary to malignant melanoma. This is the first case report of an intracerebral tumor producing an inferior altitudinal field defect.- - - - - - - - - - ranking = 2.1081233817966keywords = eye, ocular (Clic here for more details about this article) |
4/375. Acquired convergence-evoked pendular nystagmus in multiple sclerosis.Nystagmus seen only with convergence is unusual. We describe four cases of acquired convergence-evoked pendular nystagmus in patients with multiple sclerosis. The nystagmus was horizontal and asymmetric in all patients. eye movement recordings in one subject showed a conjugate rather than a convergent-divergent relationship of the phase of movement between the two eyes. All patients had evidence of optic neuropathy and cerebellar dysfunction. Occlusion of either eye during fixation of near targets led to divergent drift of the covered eye and a decrease in nystagmus. Intravenous scopolamine reduced nystagmus in one patient. Base-in prisms alleviated symptoms of oscillopsia at near and improving reading visual acuity. Convergence-evoked pendular nystagmus may be more common than currently appreciated, particularly among patients with multiple sclerosis.- - - - - - - - - - ranking = 3.3243701453897keywords = eye (Clic here for more details about this article) |
5/375. Bilateral periopticointrascleral hemorrhages associated with traumatic child abuse.PURPOSE: To report a case of bilateral periopticoscleral hemorrhages associated with traumatic child abuse. methods: Postmortem gross examination and histopathologic studies of both eyes and the optic nerves of a 6-month-old infant who died from subdural hematoma. RESULTS: Gross examination and histopathologic step sections disclosed bilateral intrascleral hemorrhages around both optic nerves. In addition, bilateral diffuse multilayered retinal, vitreous, and sublaminar (beneath the internal limiting membrane) hemorrhages were present. CONCLUSION: Periopticointrascleral hemorrhages are characteristic of blunt head trauma and may constitute important forensic evidence in cases of suspected child abuse.- - - - - - - - - - ranking = 1.1081233817966keywords = eye (Clic here for more details about this article) |
6/375. Optic neuropathy in systemic lupus erythematosus and antiphospholipid syndrome (APS): clinical features, pathogenesis, review of the literature and proposed ophthalmological criteria for APS diagnosis.Optic neuropathy is a well-known ocular manifestation occurring in patients with systemic lupus erythematosus (SLE), and it remains one of the major causes of blindness in these patients. We report data from six SLE patients with optic neuropathy, one of whom was considered to have antiphospholipid syndrome (APS). This patient had monolateral optic neuropathy, whereas the other five SLE patients had bilateral optic nerve disease. We believe that the monolateral occurrence of optic neuropathy in our patient can be considered as a 'focal' neurological disease due to a thrombotic event involving the ciliary vasculature. Conversely, bilateral optic nerve damage in SLE could be considered to be a 'general' neurological disease due to different immunological mechanisms, such as vasculitis. Additionally, the literature on SLE patients affected by optic neuropathy is reviewed to evaluate the major clinical features, particularly neurological features. In reviewing the literature, it appears that bilateral optic neuropathy in SLE occurs more frequently than monolateral optic neuropathy, and the main neurological manifestation seen in these patients is transverse myelitis, particularly in SLE patients with bilateral optic nerve disease. Finally, we propose a clinico-ophthalmological spectrum of APS and outline the ocular clinical manifestations that can be considered as diagnostic for the syndrome.- - - - - - - - - - ranking = 2keywords = ocular (Clic here for more details about this article) |
7/375. Ophthalmic abnormalities in patients with cutaneous T-cell lymphoma.PURPOSE: To determine the frequency of ophthalmic abnormalities in patients with cutaneous T-cell lymphoma (mycosis fungoides and sezary syndrome) and T-cell lymphoma involving the skin and to describe the clinical course of the disease with selected examples. methods: A computerized diagnostic retrieval system was used to identify all patients with T-cell lymphoma involving the skin who were examined at the Mayo Clinic (Rochester, minnesota) between January 1, 1976 and December 31, 1990. The medical records of affected patients were reviewed. RESULTS: During the 15-year interval from 1976 through 1990, cutaneous T-cell lymphoma was diagnosed in 2,155 patients. Of these 2,155 patients, 42 (1.95%; 26 male and 16 female) had at least 1 ophthalmic abnormality attributable to the disease. The diagnoses in these 42 patients were mycosis fungoides in 19, clinical variants of T-cell lymphoma of the skin (most commonly, peripheral T-cell lymphoma) in 11, and sezary syndrome in 12. Cicatricial eyelid ectropion was the most common finding, affecting 17 (40.4%) of the 42 patients. Thirty-seven patients had findings that, although probably not a direct consequence of cutaneous T-cell lymphoma, have been cataloged in previous studies. CONCLUSION: Although ophthalmic abnormalities in patients with cutaneous T-cell lymphoma are relatively uncommon, the manifestations of the disease are diverse and frequently difficult to treat.- - - - - - - - - - ranking = 1.1081233817966keywords = eye (Clic here for more details about this article) |
8/375. Acquired mitochondrial impairment as a cause of optic nerve disease.BACKGROUND: blindness from an optic neuropathy recently occurred as an epidemic affecting 50,000 patients in cuba (CEON) and had clinical features reminiscent of both tobacco-alcohol amblyopia (TAA) and Leber's hereditary optic neuropathy (Leber's; LHON). Selective damage to the papillomacular bundle was characteristic, and many patients also developed a peripheral neuropathy. Identified risk factors included vitamin deficiencies as well as exposure to methanol and cyanide. In all 3 syndromes, there is evidence that singular or combined insults to mitochondrial oxidative phosphorylation are associated with a clinically characteristic optic neuropathy. PURPOSE: First, to test the hypothesis that a common pathophysiologic mechanism involving impairment of mitochondria function and, consequently, axonal transport underlies both genetic optic nerve diseases such as Leber's and acquired toxic and nutritional deficiency optic neuropathies. According to this hypothesis, ATP depletion below a certain threshold leads to a blockage of orthograde axonal transport of mitochondria, which, in turn, leads to total ATP depletion and subsequent cell death. Second, to address several related questions, including (1) How does impaired energy production lead to optic neuropathy, particularly since it seems to relatively spare other metabolically active tissues, such as liver and heart? (2) Within the nervous system, why is the optic nerve, and most particularly the papillomacular bundle, so highly sensitive? Although there have been previous publications on the clinical features of the Cuban epidemic of blindness, the present hypothesis and the subsequent questions have not been previously addressed. methods: patients in cuba with epidemic optic neuropathy were personally evaluated through a comprehensive neuro-ophthalmologic examination. In addition, serum, lymphocytes for dna analysis, cerebrospinal fluid (CSF), sural nerves, and eyes with attached optic nerves were obtained from Cuban patients, as well as from Leber's patients, for study. Finally, we developed an animal model to match the low serum folic acid and high serum formate levels found in the CEON patients, by administering to rats low doses of methanol after several months of a folic acid-deficient diet. Optic nerves and other tissues obtained from these rats were analyzed and compared with those from the Cuban patients. RESULTS: patients from the Cuban epidemic of optic neuropathy with clinical evidence of a selective loss of the papillomacular bundle did much better once their nutritional status was corrected and exposure to toxins ceased. patients with CEON often demonstrated low levels of folic acid and high levels of formate in their blood. Histopathologic studies demonstrated losses of the longest fibers (in the sural nerve) and those of smallest caliber (papillomacular bundle) in the optic nerve, with intra-axonal accumulations just anterior to the lamina cribrosa. Our animal model duplicated the serologic changes (low folic acid, high formate) as well as these histopathologic changes. Furthermore, ultrastructural examination of rat tissues demonstrated mitochondrial changes that further matched those seen on ultrastructural examination of tissues from patients with Leber's. CONCLUSION: mitochondria can be impaired either genetically (as in Leber's) or through acquired insults (such as nutritional or toxic factors). Either may challenge energy production in all cells of the body. While this challenge may be met through certain compensatory mechanisms (such as in the size, shape, or number of the mitochondria), there exists in neurons a threshold which, once passed, leads to catastrophic changes. This threshold may be that point at which mitochondrial derangement leads to such ATP depletion that axonal transport is compromised, and decreased mitochondrial transport results in even further ATP depletion. neurons are singularly dependent on the axonal transport of mitochondria. (- - - - - - - - - - ranking = 1.1081233817966keywords = eye (Clic here for more details about this article) |
9/375. Anterior ischaemic optic neuropathy in a patient with optic disc drusen.BACKGROUND: Although visual field defects are well-known complications of optic disc drusen, reduction in visual acuity with this condition is rare. METHOD/RESULTS: We report on a 68-year-old male with bilateral optic disc drusen who presented with monocular loss of vision in the right eye associated with an inferior altitudinal visual field defect and signs consistent with acute anterior ischaemic optic neuropathy, confirmed on fluorescein angiography. He also had a left inferior nasal step, but no evidence of glaucomatous cupping. The disc drusen were documented clinically and on B scan ultrasound and computed tomography. CONCLUSIONS: The diagnosis of acute anterior ischaemic optic neuropathy should be considered in patients with optic disc drusen who present with reduced visual acuity, particularly when the visual loss has been acute and non-progressive and is associated with altitudinal field loss and characteristic fluorescein angiography signs.- - - - - - - - - - ranking = 2.1081233817966keywords = eye, ocular (Clic here for more details about this article) |
10/375. Congenital intraorbital optic nerve cyst. Case report.Congenital cystic lesions of the optic nerve are exceedingly rare; only one case is reported in the world literature. The authors describe a case of congenital simple glial cyst in the intraorbital portion of the optic nerve with a brief review of the literature and comment on its histogenesis. A 45-day-old male infant was admitted to the hospital because of progressive proptosis and hypotropia in the left eye, which had been present since birth. magnetic resonance imaging of the left orbit revealed an ovoid, well-demarcated, homogeneous cystic mass in the intraconal retrobulbar area. The mass compressed the left eyeball with downward and lateral displacement. The wall of the cystic mass was very thin, and a needle puncture of the cyst released clear, colorless, watery fluid. The cystic wall was lined by loose astroglial nerve fibers with some scattered glial cells.- - - - - - - - - - ranking = 2.2162467635931keywords = eye (Clic here for more details about this article) |
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