Neuro-Ophthalmological Findings in Patients with Posterior Circulation Stroke
Vivek Lal in A Clinical Approach to Neuro-Ophthalmic Disorders, 2023
Lesions of the posterior inferior vermis in the territory of the medial branch of posterior inferior cerebellar artery (mPICA) are known to cause vertigo and vestibulo-ocular abnormalities.25,26 Vertigo is often severe and is usually accompanied by nausea and vomiting. The entire symptom complex is dominated by vestibular symptoms and signs often leading to the erroneous diagnosis of labyrinthitis, peripheral vestibular disorder, or Meniere's disease. In patients with mPICA infarcts, the eyes may rest conjugately deviated to the side of the lesion-lateropulsion. Foveal smooth pursuit is impaired in all directions and there often is horizontal nystagmus. The nystagmus is usually in both directions of gaze but has larger amplitude when gaze is directed toward the side of the lesion. The posterior inferior vermis contains the nodulus and a major portion of the vestibulocerebellum receiving mostly projections from the vestibular nuclei. Periodic alternating nystagmus can be found in patients with an acute infarct limited to the nodulus.27 Spontaneous horizontal nystagmus occur in the primary eye position and revers direction with cycles of about 2 minutes. The nystagmus disappear with eye fixation. Head shaking in the horizontal position elicit downbeat nystagmus. Some patients with lesions of the most posterior inferior vermis have prominent downbeat nystagmus. Most such patients have had craniocervical junction abnormalities such as Arnold Chiari syndrome with downward herniation of the cerebellar tonsils and bilateral abnormalities.
Nystagmus
K. Gupta, P. Carmichael, A. Zumla in 100 Short Cases for the MRCP, 2020
Nystagmus can occur due to several conditions: Congenital.Cerebellar disease.Brainstem lesions.3rd, 4th or 6th cranial nerve lesions.Vestibular disease.Due to drugs, e.g., alcohol, phenytoin, phenobarbital, diazepam.
Chronic Fatigue Syndrome: Limbic Encephalopathy in a Dysregulated Neuroimmune Network
Jay A. Goldstein in Chronic Fatigue Syndromes, 2020
The most common visual complaint in CFS patients is intermittent blurred vision, probably due to variations in the autonomic input to muscles which move the lens. Problems with accomodation are typical. Blurred vision often responds to nitroglycerin in very low doses. Nitroglycerin is metabolized into nitric oxide, a neurotransmitter which may be low in CFS (see Conclusion). Nystagmus has sometimes been detected by neuro-ophthalmologists at the University of Southern California School of Medicine, but is not frequently seen on a routine eye exam.27 Photophobia is also a frequent complaint, and is probably due to ciliary muscle spasm. It can be treated to an extent with prostaglandin-inhibiting ophthalmic solution. Patients sometimes report that their concentration is impaired because the lines they are reading jump around and jumble. Some are unable to read for this reason. A less common, perhaps related complaint is that objects in the environment seem to move up and down, or back and forth. Oscillopsia may be seen with lesions of the vestibular nuclei, or in the parieto-occipital area. In the latter case, the illusion is present only in the contralateral hom-onymous visual field, not the finding in CFS. Night vision is also impaired, and is most troublesome when driving, when oncoming headlights appear overly bright. This phenomenon may be related to photophobia.
Fleck-like lesions in CEP290-associated leber congenital amaurosis: a case series
Published in Ophthalmic Genetics, 2022
Tomas S. Aleman, Erin C. O’Neil, Katherine E. Uyhazi, Kelsey M. Parchinski, Arlene J. Santos, Mariejel L. Weber, Sherice P. Colclough, Andrew S. Billek, Xiaosong Zhu, Bart P. Leroy, Emma C. Bedoukian
All patients carried homozygous or compound heterozygous mutations in CEP290 (Table 1). Three of the five patients shared the frequent intronic CEP290 pathogenic variant (c.2991+1655A>G). All patients were symptomatic before one year of age with nystagmus and inability to see or track visual targets. Full-field electroretinograms (ffERGs) were non-detectable, leading to the diagnosis of LCA. They had brain MRI and renal ultrasounds around the time of diagnosis. In two patients the ocular findings were associated with systemic abnormalities (Table 1), namely kidney cystic disease (Patient 3, P3, and P4), delayed speech, cerebellar vermis hypoplasia (Joubert syndrome, P3), and possible autism spectrum disorder (P4). Visual acuities were profoundly abnormal from 20/250 to no light perception (NLP) with a hyperopic refractive error (Table 1).
Selected Ophthalmological Features in Children with Septo-Optic Dysplasia and Optic Nerve Hypoplasia
Published in Neuro-Ophthalmology, 2022
Michael S. Salman, Shakhawat Hossain, Elizabeth Carson, Chelsea A. Ruth, Ian H. Clark
Nystagmus was reported in about half of our patients. The prevalence of nystagmus among different studies is variable (18.8–94.1%, Table 4) reflecting the different study populations, their sizes, and the laterality, if any, of the hypoplastic optic discs. In our study, nystagmus was present more commonly when BCVA was decreased in both eyes and when both optic nerve discs were hypoplastic. Such findings are consistent with other studies.28,29 The presence of nystagmus reflects failure of a gaze-holding mechanism that has never been calibrated by visual input in bilateral ONH. Ocular drifts cannot be corrected since fixation mechanisms depends on an intact visual system. Thus, ocular oscillations occur.30 ONH should always be considered as a possible explanation for nystagmus in infancy.
Identification of ALMS1 pathogenic variants in Chinese patients with Alström syndrome
Published in Ophthalmic Genetics, 2022
Lijuan Huang, Maosheng Guo, Yunyu Zhou, Tianwei Liang, Ningdong Li
In our patients, not all of them have typical manifestations of Alström syndrome. The only common feature is nystagmus, which occurs very early in their life. However, there are many factors related to the cause of nystagmus. In addition, due to many factors, including the young age of the children, the wide range of symptoms and great variability in presentations, it is challenging to make a correct diagnosis for the very rare Alström syndrome. With the exceptions of the Patients 01 and 03 who were considered to have Alström syndrome or Bardet-Biedl syndrome because they showed poor vision, nystagmus, photophobia, and obesity, the other three cases were not diagnosed as Alström syndrome initially. Patients with Alström syndrome are finally confirmed by molecular diagnosis. Because the characteristic features of Alström syndrome often become more evident as a child grows, molecular diagnosis is not only helpful for doctors to make diagnosis but also helpful for doctors to guide the affected children's parents to choose interventions in advance based on disease progression, for example, to prevent diabetes.
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