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Clinical Examination in Neuro-Ophthalmology
Published in Vivek Lal, A Clinical Approach to Neuro-Ophthalmic Disorders, 2023
Selvakumar Ambika, Krishnakumar Padmalakshmi
Interpretation of visual fields should go hand in hand with clinical findings. Disease of the retina may produce focal defects or scotomas. Macular lesions produce central scotomas and branch retinal artery occlusion can cause focal field defects. Constricted visual fields not involving fixation are seen in retinitis pigmentosa. Central visual field defects in the absence of a macular lesion are typical, although not exclusively seen in optic nerve lesions. Altitudinal defects can be seen in optic neuritis and ischemic optic neuropathies. Toxic, nutritional and hereditary optic neuropathies produce central/paracentral defects. Lesions of chiasm cause bitemporal hemianopic defect due to the crossing over of nasal retinal fibers at the chiasm. Homonymous hemianopia is produced in retrochiasmal lesions (Figure 1.19). Thus, the vertical meridian separating the nasal and temporal hemifield has crucial importance in lesions of the chiasm, optic radiation and visual cortex. Table 1.8 describes visual field defects and its differential diagnosis.
Ophthalmic Emergencies
Published in Anthony FT Brown, Michael D Cadogan, Emergency Medicine, 2020
Anthony FT Brown, Michael D Cadogan
A preceding history of transient episodes of monocular visual loss ‘amaurosis fugax’ suggests embolic branch retinal artery occlusion. Perform a work-up for a transient ischaemic attack including a duplex carotid ultrasound, and commence aspirin – see page 95.
Case 13: Loss of Vision and a Maculopapular Rash
Published in Layne Kerry, Janice Rymer, 100 Diagnostic Dilemmas in Clinical Medicine, 2017
It is difficult to determine whether the patient's vision was truly lost suddenly, or if he only noticed this when driving. There are a limited number of conditions that lead to sudden visual loss, including central or branch retinal artery occlusion – this typically results in sudden and painless visual loss. Underlying causes include hypercoagulable states, diabetes mellitus, hypertension, hypercholesteroalemia and atherosclerosis (particularly carotid atherosclerosis). Giant cell arteritis may also lead to central retinal occlusion. Amaurosis fugax may precede visual loss. On fundoscopy, the disc will appear swollen and pale.
Proceedings of the 43nd Annual Upper Midwest Neuro-Ophthalmology Group Meeting, July 23, 2021 and Second Virtual Upper Midwest Neuro-Ophthalmology Group Meeting
Published in Neuro-Ophthalmology, 2021
Deena Tajfirouz, Casey Judge, John J. Chen, Collin McClelland
Ahmad Halawa MD, University of Michigan, presented a case of a 61-year-old woman who developed congestive orbitopathy and bilateral retinal, optic nerve, and cerebral infarctions after removal of a chipped molar tooth. Three days following the procedure she presented with facial pain, swelling, and blurred vision in both eyes. She was febrile to 39 °C with a neutrophilic (85.6%) leukocytosis of 22,000. Initial ophthalmologic assessment was notable for bilateral proptosis, poor pupillary reactivity bilaterally, and elevated intraocular pressures (IOP) to 39 mmHg in the right eye and 43 mmHg in the left eye. Fundus examination demonstrated inferior branch retinal artery occlusion and distal retinal pallor in the right eye and a normal left fundus examination. Imaging revealed ipsilateral masticator and pterygoid muscle abscesses, as well as thrombosis of the right internal jugular vein and sigmoid sinus, both cavernous sinuses and superior ophthalmic veins, and restricted diffusion of both optic nerves and corona radiata. She was diagnosed with catastrophic Lemierre syndrome. She underwent emergent bilateral canthotomy with cantholysis with improvement in IOP to 25 mmHg and 14 mmHg. Broad spectrum antibiotics were initiated, but despite this she went into septic shock requiring intubation and vasopressors.
Posterior Segment Manifestations of Cat-scratch Disease: A Mini-review of the Clinical and Multi-modal Imaging Features
Published in Neuro-Ophthalmology, 2021
Omer Karti, Ferdane Ataş, Ali Osman Saatci
CSD can present with various retinal vascular changes. Branch retinal artery or vein occlusion (predominantly arteriolar occlusion) may sometimes be seen in patients with ocular CSD, with or without neuroretinitis, whereas central retinal vein and/or artery occlusion has rarely been reported.15,28–32 The retinal vascular occlusion rate varies between 7 and 23% and it can sometimes be the only sign of CSD.4,15,17,31 Thus, young patients with branch retinal artery occlusion should be investigated for associated CSD when there is no obvious standard risk factors for the retinal vascular occlusion.12,15 These patients usually present with decreased visual acuity and/or visual field defects. Naturally, the severity of the visual disturbance depends on the proximity of the affected vessel to the macula.4 Direct mechanical compression on the vessels by the focus of retinitis or oedematous optic nerve has been blamed in the pathogenesis of vascular occlusion. Thrombogenic mediators triggered by the bacteria may contribute to vascular endothelial damage and may also play a role in arterial occlusion (obliterative or thrombogenic vasculitis).15,28–32
Retinopathy and Systemic Disease Morbidity in Severe COVID-19
Published in Ocular Immunology and Inflammation, 2021
Jessica G. Shantha, Sara C Auld, Casey Anthony, Laura Ward, Max W. Adelman, Cheryl L. Maier, Kenneth W. Price, Jesse T Jacob, Tolulope Fashina, Casey Randleman, Lucy T. Xu, Joshua Barnett, Ofer Sadan, Prem A. Kandiah, Jay B. Varkey, Colleen S. Kraft, Nadine Rouphael, Susanne Linderman, Rafi Ahmed, Carolyn Drews-Botsch, Jesse J. Waggoner, Max Weinmann, David J. Murphy, Steven Yeh
Branch retinal artery occlusion was observed in one patient from this series. Albeit a rare finding, arterial occlusive events can lead to severe vision impairment or blindness. While several recent case reports have identified temporal associations between retinal artery and venous occlusion with COVID-19,15–18 further studies are needed to define the precise mechanisms and risk factors for these potentially vision-compromising complications. Anterior segment findings were also observed in our cohort, although less commonly than retinopathy, with conjunctival injection and chemosis in 10–20% of patients. However, given the frequency of prone positioning and sedation with mechanical ventilation, these findings may be attributable to the ICU environment and care rather than direct effects of COVID-19.