Neuro ophthalmology

Binocular stereopsis, or stereo vision, is the ability to derive information about how far away objects are, based solely on the relative positions of the object in the two eyes. It depends on both sensory and motor abilities. In this review, I briefly outline some of the neuronal mechanisms supporting stereo vision, and discuss how these are disrupted in strabismus. I explain, in some detail, current methods of assessing stereo vision and their pros and cons. Finally, I review the evidence supporting the clinical importance of such measurements.

Published in 2005 by Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton. FL 33487-2742 © 2005 by Taylor & Francis Group. LLC No claim to original US Government works Printed in the United States of America on acid-free paper 10 987654 3 2 1 ...

Binocular stereopsis, or stereo vision, is the ability to derive information about how far away objects are, based solely on the relative positions of the object in the two eyes. It depends on both sensory and motor abilities. In this review, I briefly outline some of the neuronal mechanisms supporting stereo vision, and discuss how these are disrupted in strabismus. I explain, in some detail, current methods of assessing stereo vision and their pros and cons. Finally, I review the evidence supporting the clinical importance of such measurements.

METHODS:
A 32 years old female presented with Sudden painless loss of vision RE for 20 days ,Associated with pain during eye movements and headache and gives History of viral fever 15 days back. On  Ocular Examination her Best corrected visual acuity- RE -6/36; LE -6/9. Left eye pupil was having RAPD. Visual field RE revealed centrocaecal scotoma. Fundus- RE Revealed optic disc swelling with blurred margins with dilated tortuous veins and macular edema. LE- WNL. CT & MRI brain WNL.  Diagnosis of idiopathic optic neuritis made. Treatment as per Optic Neuritis was given. Visual acuity of RE improved to 6/12 after two weeks. After 20 days, she presented again with complaints of further worsening of visual acuity. Her visual acuity was 6/60 in RE. OCT of RE showed RNFL thickening & macular oedema. Her Serum CMV - IgG > 1.10 , Positive. Diagnosis of Cytomegalovirus Neuroretinitis was made. Treatment was given for CMV neuroretinitis. IV Ganciclovir induction therapy and maintenance was given.  Patient respond to the treatment. At the end of 6 month her BCVA was 6/9 in Right Eye.
CONCLUSION:
Initially patient presented  with all characteristic features of optic neuritis, but serological investigations turned out to be CMV  infection and therefore diagnosis of CMV neuroretinitis was made without any systemic manifestations of cytomegalovirus infection therefore idiopathic optic neuritis should be investigated  thoroughly.

A 6.5-year-old male neutered Trailhound was admitted for hyperacute, nonprogressive, left-sided hemipare-sis. Physical and neurologic examination revealed nonpainful, left-sided poorly ambulatory hemiparesis, decreased left-sided postural reactions and thoracic limbs hyporeflexia. Neuroanatomic localisation was consistent with a left-sided C6-T2 myelopathy. Haematology and biochemistry revealed nonspecific abnormalities. Magnetic resonance imaging of the neck revealed a focal intramedullary lesion at the level of C6-C7 vertebrae compatible with acute hydrated noncompressive nucleus pulposus extrusion or ischemic myelopa-thy. During the second day of hospitalization, the dog developed convergence-retraction nystagmus, up-gaze palsy and eyelid retraction (Collier's sign) compatible with dorsal midbrain syndrome. Magnetic resonance imaging of the brain revealed a focal lesion compatible with dorsal midbrain ischemic infarct. Further clinico-pathologic testing, thoracic and abdominal imaging were unremarkable. Ischemic encephalopathy of unknown etiology was additionally diagnosed. Physiotherapy was performed therapeutically. At 1-year follow up the dog was normal. This is an unusual report of a dog with myelopathy followed by ischemic encephalopathy with manifestation of convergence-retraction nystagmus in the absence of vestibular signs. This saccadic intrusion is a characteristic clinical manifestation of a dorsal midbrain syndrome localization. The importance of a complete differential diagnoses list formation in a dog with ischemic encephalopathy which leads to a thorough diagnostic investigation plan is highlighted. Moreover, this report contributes to the enrichment of the clinical reasoning veterinary literature on convergence-retraction nystagmus. To the authors' knowledge, this is the second case report (fourth dog) to describe convergence-retraction nystag-mus in dogs as a manifestation of dorsal midbrain syndrome.

Abstract: Eales disease is an eponym after a British ophthalmologist Henry Eales. The etiology behind Eales disease is ill-understood and stands controversial. Various systemic diseases associated with peripheral retinal revascularization and Retinal vasculitis could imitate the proliferative and inflammatory phases of Eales’ disease, respectively. We present a case of a 30 years old female patient with Eales disease and discuss the clinical features, treatment plan and its outcome in our patient.

Introduction: One of the autoimmune disease is Myasthenia gravis. Myasthenia gravis is an autoimmune disease characterized by a fluctuating weakness of voluntary muscles. The weakness of myasthenic patients is due to an antibodymediated autoimmune attack against acetylcholine receptor at neuromuscular junction. Normally impulses travel down the nerve and nerve endings release a substance called acetylcholine. Acetylcholine binds or attaches to receptor on the muscle and makes the muscle contract. Objective: To Diagnose the Myasthenia gravis patients prevent the autoimmune disease process with help of adjuvant therapy.