| Identifier |
166-25 |
| Title |
Pseudo-Internculear Ophthalmoplegia |
| Creator |
Shirley H. Wray, MD, PhD, FRCP |
| Contributors |
Ray Balhorn, Video Compressionist |
| Affiliation |
(SHW) Professor of Neurology, Harvard Medical School; Director, Unit for Neurovisual Disorders, Massachusetts General Hospital, Boston, Massachusetts |
| Subject |
Unilateral Ptosis; Pseudo-internuclear Ophthalmoplegia; Bilateral Weakness of Adduction; Tensilon Test; Ocular Myasthenia Gravis; Unilateral Myasthenia Gravis; Internuclear Ophthalmoplegia |
| History |
This 32 year old man had the acute onset of double vision followed very quickly by a drooping of the left eyelid. Past History: Negative for any previous episode of double vision No history of strabismus as a child No fatigue, neck weakness, difficulty in chewing or swallowing Family History: Negative for neurologic disease Neuro-ophthalmological Examination: Unilateral ptosis OS Lid retraction OD Adduction weakness right eye on gaze left Adduction weakness left eye on gaze right No abducting nystagmus Normal convergence Vertical gaze full OD Vertical upgaze slightly impaired OS Intravenous Tensilon Test (edrophonium chloride): Patient received a test dose of 0.1 ml with no side effects Next dose of 0.3 ml resulted in immediate recovery of full adduction of both eyes. The full dose of 1 ml (10 mg) was not given as the test was positive. Antibody Studies: This patient was seen in the 1970's and predated the detection of antiacetylcholine receptor antibodies. Chest X-Ray: Normal Diagnosis: Pseudo-internuclear opthalmoplegia Ocular Myasthenia Gravis Medication: Mestinon 60 mg. 1 tablet q.6.h. On medication recovered, horizontal gaze improved and convergence and vertical gaze returned to normal. The patient was lost to follow-up. |
| Anatomy |
Ptosis: Ptosis is defined as the lid covering more than 2 mm of the cornea. Ptosis is routinely measured by documenting the width of the palpebral fissure in millimeters with the eye in primary gaze and the eyebrow held down. Approximately 50% of patients with ocular myasthenia gravis present with ptosis. More than 90% eventually develop eye movement abnormalities and typical ocular myasthenia. Of those patients who present only with ocular symptoms, half persist with purely ocular myasthenia and half go on to develop generalized myasthenia gravis. Of those who develop generalized myasthenia gravis, most do so within 2 years of the onset of ocular symptoms. |
| Pathology |
Myasthenia gravis (MG) is an autoimmune disease caused by sensitized T-helper cells and an IgG-directed attack on the nicotinic acetylcholine receptor of the neuromuscular junction (NMJ). The mechanism of antibody damage to the receptor and motor endplate probably involves several steps. 1. There is a complement-directed attack with the destruction of acetylcholine receptor and the junctional folds. 2. Binding of the antibody to the receptor can cause receptor blockade. 3. The abnormal and reduced numbers of acetylcholine receptors lead to impaired NMJ transmission. 4. In post synaptic disorders such as MG, the number of quanta of acetylcholine released by each nerve stimulus is normal, but the effect of each quantum on its receptor is reduced. 5. The net result is a lower endplate potential and a reduced safety factor of transmission at the NMJ. Clinically this manifests as pathologic fatigability, that is, progressive muscle weakness with use - the hallmark of MG. Patients typically improve after rest or upon arising in the morning, with worsening as the day passes. In MG, fatigue is limited to muscular fatigue alone and often progresses to frank muscle weakness. |
| Disease/Diagnosis |
Ocular Myasthenia Gravis |
| Clinical |
This patient with pseudo-internuclear ophthalmoplegia illustrates how closely bilateral weakness of adduction due to ocular myasthenia gravis can mimic a brainstem bilateral internuclear ophthalmoplegia due to a lesion of the medial longitudinal fasciculus in the brainstem. The significant signs are: • Unilateral ptosis OS • Retraction of the eyelid OD • Paresis of adduction of the right eye looking left • Paresis of adduction of the left eye looking right • No abducting nystagmus • Impaired upgaze left eye only • Convergence impaired The prompt positive response to intravenous tensilon test is shown with: • Recovery of ptosis OS • Recovery of full horizontal eye movements |
| Presenting Symptom |
Double vision |
| Ocular Movements |
Unilateral Ptosis; Pseudo-internuclear Ophthalmoplegia; Bilateral Weakness of Adduction |
| Neuroimaging |
No neuro-imaging studies are available in this patient. |
| Treatment |
Mestinon 60 mg, one tablet t.i.d. |
| Etiology |
Autoimmune disease |
| Supplementary Materials |
PowerPoint Presentation: Ocular Myasthenia Gravis: Past, Present and Future: http://library.med.utah.edu/NOVEL/Wray/PPT/Ocular_Myasthenia_Gravis_guest_lecture.ppt Victoria S. Pelak, M.D. University of Colorado Health Sciences Center |
| References |
1. Cogan DG. Myasthenia gravis: a review of the disease and a description of lid twitch as a characteristic sign. Arch Ophthalmol 1965;74:217-221. http://www.ncbi.nlm.nih.gov/pubmed/14318498 2. Cogan DG, Yee RD, Gittinger J. Rapid eye movements in myasthenia gravis. I Clinical observations. Arch Ophthalmol 1976;94:1083-1085. http://www.ncbi.nlm.nih.gov/pubmed/938289 3. Daroff RD. The office tensilon test for ocular myasthenia gravis. Arch Neurol 1986:43:843-844. http://www.ncbi.nlm.nih.gov/pubmed/3729767 4. Elrod RD, Weinberg DA. Ocular myasthenia gravis. Ophthalmol Clin North Am 2004;17:275. http://www.ncbi.nlm.nih.gov/pubmed/15337189 5. Glaser JS. Myasthenic psuedo-internuclear ophthalmoplegia. Arch Ophthalmol. 1966 Mar;75(3):363-366. http://www.ncbi.nlm.nih.gov/pubmed/5903821 6. Kaminski HJ, LI Z, Richmonds C, Ruff RL, Kusner L. Susceptibility of Ocular tissues to Autoimmune Diseases. Ann N.Y. Acad Sci 2003;998:362-374. http://www.ncbi.nlm.nih.gov/pubmed/14592898 7. Kupersmith MJ, Latkany R, Homel P. Development of generalized disease at 2 years in patients with ocular myasthenia gravis. Arch Neurol 2003;60:243-248. http://www.ncbi.nlm.nih.gov/pubmed/12580710 8. Leigh JR,Zee DS. Diagnosis of Peripheral Ocular Motor Palsies and Strabismus. Ch 9:385-474. In: The Neurology of Eye Movements 4th Edition Oxford University Press, NY 2006. 9. Meriggioli MN, Sanders DB. Myasthenia gravis: diagnosis. Semin Neurol 2004;24:31. http://www.ncbi.nlm.nih.gov/pubmed/15229790 10. Pelak VS, Quan D. Ocular Myasthenia Gravis. In: Rose BD (Ed) UpToDate, Wellesley, MA. 2006 11. Pierrot-Deseilligny C, Michelin T. Myasthenic internuclear pseudo-ophthalmoplegia. Rev Neurol (Paris). 1983;139:527-528. http://www.ncbi.nlm.nih.gov/pubmed/6648206 12. Swick HM. Pseudointernuclear ophthalmoplegia in acute idiopathic polyneuritis (Fisher's syndrome). Am J Ophthalmol. 1974;77(5):725-728. http://www.ncbi.nlm.nih.gov/pubmed/4823781 13. Valls-Canals J, Povedano M, Montero J, Pradas J. Stimulated single-fiber EMG of the frontalis and orbicularis oculi muscles in ocular myasthenia gravis. Muscle Nerve 2003;28:501-503. http://www.ncbi.nlm.nih.gov/pubmed/14506723 14. Vincent A, Newsom-Davis J. Acetylcholine receptor antibody as a diagnostic test for myasthenia gravis: results in 153 validated cases and 2967 diagnostic assays. J Neurol Neurosurg Psychiatry 1985;48:1246-1252. http://www.ncbi.nlm.nih.gov/pubmed/4087000 15. Vincent A, Newsom-Davis J. Anti-acetylcholine receptor antibodies. J Neurol Neurosurg Psychiatry 1980;43:590-600. http://www.ncbi.nlm.nih.gov/pubmed/7400823 16. Wray SH, Pavan-Langston D. A reevaluation of edrophonium chloride (Tensilon) tonography in the diagnosis of myasthenia gravis. Neurology 1971;21:586-593. http://www.ncbi.nlm.nih.gov/pubmed/4327153 |
| Language |
eng |
| Format |
video/mp4 |
| Type |
Image/MovingImage |
| Source |
16 mm Flim |
| Relation is Part of |
163-10, 163-11 |
| Collection |
Neuro-Ophthalmology Virtual Education Library - Shirley H. Wray Neuro-Ophthalmology Collection: https://novel.utah.edu/Wray/ |
| Publisher |
North American Neuro-Ophthalmology Society |
| Holding Institution |
Spencer S. Eccles Health Sciences Library, University of Utah |
| Rights Management |
Copyright 2002. For further information regarding the rights to this collection, please visit: https://NOVEL.utah.edu/about/copyright |
| ARK |
ark:/87278/s6xd3z8b |
| Setname |
ehsl_novel_shw |
| ID |
188639 |
| Reference URL |
https://collections.lib.utah.edu/ark:/87278/s6xd3z8b |
