Identifier |
163-10 |
Title |
Bilateral Ptosis |
Creator |
Shirley H. Wray, MD, PhD, FRCP |
Affiliation |
(SHW) Professor of Neurology, Harvard Medical School; Director, Unit for Neurovisual Disorders, Massachusetts General Hospital, Boston, Massachusetts |
Subject |
Bilateral Ptosis; Decompensated Phoria; Myasthenic Lid Twitch; Tensilon Test; Bilateral Myasthenia Gravis; Ocular Myasthenia Gravis; Ptosis - Myasthenic |
History |
The patient is a 65 year old physician who presented with intermittent drooping of his eyelids, particularly at the end of the day. He found that if he gently closed his eyes when he came to a stop in his car at a set of traffic lights, his eyelids opened more fully. He subsequently developed intermittent horizontal double vision and consulted an ophthalmologist who diagnosed a decompensated phoria. He was prescribed prism glasses but frequently needed to return for a stronger prism. Ultimately, he had five pairs of prism glasses prescribed for him. The patient referred himself for a neuro-ophthalmological evaluation. Past History: Negative for previous attacks of diplopia, ptosis or fatigue Neuro-ophthalmological examination: Visual acuity: 20/25, J1 OU. Visual fields, pupils and fundus examination normal Eyelids: • Bilateral ptosis with almost complete closure of the eyes • Overaction of the orbicularis oculi muscle • Myasthenic lid twitch • Slight increase in ptosis on fatigue • Transient recovery of ptosis on gentle eye closure • Impaired ability to bury his eyelashes fully Ocular motility: • Full eye movements • Decompensated exophoria/tropia Intravenous Tensilon Test (edrophonium chloride): The patient received a test dose of 0.1 ml. He had no side effects and a dose of 0.3 ml was given with an immediate positive response and prompt elevation of the ptotic eyelids. A full dose of 1 ml (10 mg) of tensilon was not given. Chest x-ray: Normal Diagnosis: Ocular myasthenia gravis. Treatment: Mestinon 60 mg. q.4h Prednisone 20 mg daily Medication cured the ptosis and reduced the exophoria so that the patient only required a small prism correction. He was followed for over four years with no sign of generalized myasthenia gravis. |
Anatomy |
Both thymic hyperplasia and thyoma are associated with MG. Thymic hyperplasia occurs in as many as 65 to 70% of all myasthenic patients, particularly younger patients. It is characterized by infiltration of the thymus with lymphocytes and plasma cells and the formation of lymphoid follicles (germinal centers). Thymoma occur in 5 to 20% of myasthenic patients. The incidence of this tumor increases with age. Patients with thymoma tend to have more severe disease, higher serum titers of AChR antibodies, and more severe abnormalities on EMG than patients without a thymoma. Associated autoimmune diseases: There is a 23% incidence of associated autoimmune disease in patients with thymoma, although no gender predisposition or HLA antigen has been found. |
Pathology |
Myasthenia gravis 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 |
The video of this patient illustrates the eyelid signs characteristic of ocular myasthenia gravis: • Bilateral ptosis with almost complete closure of the eyes • Overaction of the orbicularis oculi muscle • Myasthenic lid twitch • Slight increase in ptosis on fatigue • Transient recovery of ptosis on gentle eye closure • Impaired ability to bury his eyelashes fully A positive intravenous tensilon test showed: • Full recovery of ptosis • Slight watering of the eyes Lid twitch - Cogan's sign In 1965 Cogan described a transient eyelid retraction occurring during refixation from downgaze to straight ahead gaze. The twitch is an "overshoot" of the eyelid. Cogan's lid twitch sign is not pathopneumonic for MG. It may occur with brainstem or peripheral ocular motor disorders. Ptosis: Ptosis is defined as the lid covering more than 2 mm of the cornea. Ptosis is measured by documenting the width of the palpebral fissure in millimeters with the eyes in primary gaze and the eyebrows held down straight. Approximately 50% of patients with MG present with ptosis. More than 90% eventually develop eye movement abnormalities and typical ocular myasthenia gravis. Of those patients who present only with ocular symptoms, half persist with purely ocular myasthenia and half go on to develop generalized MG. Of those who develop generalized MG, most do so within 2 years of the onset of ocular symptoms. |
Presenting Symptom |
Droopy eyelids |
Ocular Movements |
Bilateral Ptosis; Decompensated Phoria; Myasthenic Lid Twitch |
Etiology |
Autoimmune |
Supplementary Materials |
Ocular Myasthenia Gravis: Past, Present and Future: https://collections.lib.utah.edu/details?id=2174219 |
Date |
1979 |
References |
1. Averbuch-Heller L. Poonyathalang A, von Maydell RD, Remler BF, Hering's law for eyelids: still valid. Neurology 1995;45:1781-1782. http://www.ncbi.nlm.nih.gov/pubmed/7675249 2. Bever CT, Aquino AV, Penn AS, Lovelace RE, Rowland LP, Prognosis of ocular myasthenia. Ann Neurol 1983;14:516-519. http://www.ncbi.nlm.nih.gov/pubmed/6651238 3. 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 4. 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 5. Daroff, RB. The Office Tensilon Test for Ocular Myasthenia Gravis. Arch Neurol 1986;43:843-844. http://www.ncbi.nlm.nih.gov/pubmed/3729767 6. Elrod RD, Weinberg DA. Ocular myasthenia gravis. Ophthalmol Clin N Am 2004;17:275-309. http://www.ncbi.nlm.nih.gov/pubmed/15337189 7. Golnik KC, Pena R, Lee AG, Eggenberger ER. An Ice Test for the Diagnosis of Myasthenia Gravis. Ophthal 1999;106:1282-1286. http://www.ncbi.nlm.nih.gov/pubmed/10406606 8. Hanisch F, Eger K, Zierz S. MuSK-antibody positive pure ocular myasthenia gravis. J Neurol 2006;253: 659-660. http://www.ncbi.nlm.nih.gov/pubmed/16311895 9. 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 10. 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 11. 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. 12. Meriggioli MN, Sanders DB. Myasthenia gravis: diagnosis. Semin Neurol 2004;24:31. http://www.ncbi.nlm.nih.gov/pubmed/15229790 13. Moorthy G, Behrens MM, Drachman DB, Kirkham TH, Knox DL, Miller NR, Slamovitz TL, Zinreich SJ. Ocular pseudomyasthenia or ocular myasthenia "plus": A warning to clinicians. Neurology 1989;39:1150-1154. http://www.ncbi.nlm.nih.gov/pubmed/2771063 14 Pelak VS, Quan D. Ocular Myasthenia Gravis. In: UpToDate, Rose BD (Ed) UpToDate, Wellesley, MA. 2006. 15. Seybod ME. The Office Tensilon Test for Ocular Myasthenia Gravis. Arch Neurol 1986;43:842-843. http://www.ncbi.nlm.nih.gov/pubmed/3729766 16. Sommer N, Melms A, Weller M, Dichgans J. Ocular myasthenia gravis. A critical review of clinical and pathophysiological aspects. Doc Ophthalmol 1993;84:309-333. http://www.ncbi.nlm.nih.gov/pubmed/8156854 17. 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 18. Vincent A, Newsom-Davis J. Anti-acetylcholine receptor antibodies. J Neurol Neurosurg Psychiatry 1980;43:590-600 1980. http://www.ncbi.nlm.nih.gov/pubmed/7400823 19. Wittbrodt ET. Drugs and myasthenia gravis an update. Arch Intern Med 1997:157:399-408. http://www.ncbi.nlm.nih.gov/pubmed/9046891 |
Language |
eng |
Format |
video/mp4 |
Type |
Image/MovingImage |
Source |
16 mm film |
Relation is Part of |
166-25, 920-1 |
Collection |
Neuro-Ophthalmology Virtual Education Library: Shirley H. Wray 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/s6cr8qzs |
Setname |
ehsl_novel_shw |
ID |
188589 |
Reference URL |
https://collections.lib.utah.edu/ark:/87278/s6cr8qzs |