Fisher's One and a Half Syndrome

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Identifier 166-14
Title Fisher's One and a Half Syndrome
Ocular Movements Unilateral Internuclear Ophthalmoplegia; Unilateral Horizontal Gaze Palsy; Convergence Absent; Esotropia
Creator Shirley H. Wray, M.D., Ph.D., FRCP, Professor of Neurology Harvard Medical School, Director, Unit for Neurovisual Disorders, Massachusetts General Hospital
Contributor Primary Shirley H. Wray, MD, PhD, FRCP, Professor of Neurology, Harvard Medical School; Director, Unit for Neurovisual Disorders, Massachusetts General Hospital
Subject Unilateral Internuclear Ophthalmoplegia; Unilateral Horizontal Gaze Palsy; Convergence Absent; Esotropia; Fisher's One-and-a-Half Syndrome; Facial Palsy; Abducens Nuclear Lesion; Pontine Hemorrhage; Unilateral Gaze Palsy Hemorrhage; Abducting Nystagmus; Facial Weakness
Supplementary Materials PowerPoint Presentation: One-and-a-Half Syndrome: Shirley H. Wray, M.D., Ph.D., FRCP, Harvard Medical School
Presenting Symptom Headache Diplopia
History This young man was seen in the emergency room of his local hospital following the onset of severe headache, mild confusion and diplopia. Non-contrast CT brain scan showed: A right pontine hemorrhage He was transferred to the Massachusetts General Hospital ICU. Ocular Motility: Esotropia of the right eye Right internuclear ophthalmoplegia on gaze left with weakness of adduction OD, abducting nystagmus OS Right horizontal gaze palsy with gaze evoked nystagmus Convergence absent Full vertical gaze Right lower motor neuron facial palsy (Bell's palsy) This constellation of signs adds up to Fisher's one-and-a-half syndrome. Diagnosis: Pontine hemorrhage This case should be viewed alongside ID922-2, a young student with a cavernous angioma, a one-and-a-half syndrome and recurrent unilateral pontine hemorrhage.
Clinical This patient with a right pontine hemorrhage had Fisher's one-and-a-half syndrome with: • Esotropia of the right eye • Right internuclear ophthalmoplegia on gaze left with weakness of adduction OD, abducting nystagmus OS • Right horizontal gaze palsy with gaze evoked nystagmus • Convergence absent • Full vertical gaze • Right Bell's palsy
Neuroimaging Neuroimaging studies are unavailable in this patient.
Anatomy The one-and-a-half syndrome first described by Fisher in 1967 is characterized by, on horizontal gaze: 1. An ipsilateral gaze paresis or palsy 2. An INO on contralateral gaze 3. At rest, an exotropia of the eye contralateral to the lesion in the acute phase, or no deviation at rest, or less commonly, an esotropia of the eye ipsilateral to the lesion resulting from paresis of the sixth nerve. Horizontal gaze palsy. There are four theoretical possibilities to account for the ipsilateral horizontal gaze palsy. It may be due to a single unilateral lesion affecting: 1. The ipsilateral paramedial pontine reticular formation (PPRF) only 2. The ipsilateral abducens nucleus alone 3. Both the ipsilateral paramedial pontine reticular formation (PPRF) and the abducens nucleus, or, when two lesions are involved 4. The motoneuron root fibers of the ipsilateral abducens nucleus to the lateral rectus and the contralateral medial longitudinal fasciculus (MLF). Paramedial pontine reticular formation. The medial portions of the nucleus reticularis magnocellularis (or nucleus centralis pontis oralis and caudalis) have been designated the "paramedian pontine reticular formation" (PPRF), rostral to the abducens nucleus. The region extends from the abducens nucleus in a rostral direction toward the brachium conjunctivum and trochlear nucleus. It has been defined functionally because there are no distinct histologic boundaries. But anatomically, Graybiel, Büttner-Ennever, and Grantyn et al all showed inputs from discrete areas. Clinical findings with PPRF lesion: • Loss of horizontal saccades towards the side of the lesion • Contralateral gaze deviation, in acute phase • Gaze-evoked nystagmus on looking contralateral to the lesion • Impaired smooth pursuit and vestibular eye movements may be preserved or impaired • Bilateral lesions cause total horizontal gaze palsy and slowing of vertical saccades Abducens nucleus. The abducens nucleus contains typical motoneurons that give rise to root fibers that innervate the lateral rectus as well as internuclear neurons whose axons cross the midline and ascend via the contralateral MLF to the medial rectus subnucleus in the contralateral oculomotor (third nerve) nucleus. This projection is the main excitatory input to medial rectus motoneurons in lateral gaze. An old clinicopathologic case published by Bennett and Savill (1) described a unilateral gaze palsy with an associated "patch of softening" in the abducens nucleus without apparent involvement of neighboring structures. Clinical findings with lesion of the abducens nuclei • Loss of all conjugate movements towards the side of the lesion - "ipsilateral, horizontal gaze palsy" • Contralateral gaze deviation, in acute phase • Vergence and vertical movements are spared • In the intact hemifield of gaze, horizontal movements may be preserved, but ipsilaterally directed saccades are slow • Horizontal gaze-evoked nystagmus on looking contralaterally • Ipsilateral facial lower motor neuron palsy often associated due to involvement of the genu of the seventh cranial nerve. The gustatory fibers are spared, because these fibers are carried in the intermediate branch of the facial nerve to the nucleus solitarius of the medulla. Damage to motor neurons, in the abducens nucleus innervating the left lateral rectus muscle or damage to the fascicular portion of the sixth nerve accounts for the ipsilateral sixth nerve palsy and esotropia. The association of exotropia in the one-and-a-half syndrome was observed by Fisher and later termed "paralytic pontine exotropia" by Sharpe et al. In this distinctive supranuclear syndrome, the deviated, exotropic eye shows abduction nystagmus during attempts to move it further laterally, and there is extreme slowness of adduction saccades when the eye is used to fixate to move it to the midline. Paralytic pontine exotropia is attributed to tonic contralateral ocular deviation of the eyes, which implies acute ipsilateral involvement of the PPRF. Failure of the ipsilateral eye to deviate medially is explained by the INO. Three autopsy cases of paralytic pontine exotropia confirm the lesion site. Clinical distinction PPRF: Abducens nucleus. At the bedside distinction can be made between the manifestations of gaze palsies in lesions of the PPRF in the upper pons from those of the PPRF in the lower pons at the level of the abducens nucleus. With PPRF lesions rostral to the abducens, there is ipsilateral paralysis of saccades and pursuit, but the eyes can be driven to the side of the gaze palsy with vestibular stimulation. At the level of the abducens nucleus, lesions of the PPRF are associated with ipsilateral gaze palsy and loss of reflex vestibular (and tonic neck) movements. This presumes that there is a critical synapse within the caudal PPRF for the vestibulo-ocular pathways or that, at the very least, the functional integrity of the PPRF at that level is necessary for vestibulo-ocular eye movements. Abducens nucleus and contralateral medial longitudinal fasciculus (MLF) An identical ipsilateral gaze palsy can be produced by damage to axons of abducens neurons as they course through the brainstem, namely, the ipsilateral sixth nerve fascicle and those axons which ascend the contralateral MLF. Separation of these two anatomic sites suggests two lesions. A lateral gaze palsy that always remains conjugate is consistent with one lesion of the abducens nucleus, whereas one that is not conjugate at any time would better fit two lesions. Internuclear Ophthalmoplegia is characterized by: 1. Paresis or paralysis of adduction of the ipsilateral eye on attempted horizontal gaze to the contralateral side. 2. Horizontal jerk nystagmus in the contralateral abducting eye and 3. Typically convergence is intact if the lesion does not extend to the mesencephalon. Other associated findings are abnormalities in vertical smooth pursuit, OKN, the vertical VOR with normal vertical saccades if the INO is bilateral, gaze evoked vertical nystagmus on upward gaze more frequent than downgaze if the lesion is bilateral and skew deviation. A unilateral INO is due to the interruption of the ipsilateral MLF after it has crossed the midline caudally in the pons from its site of origin in the contralateral abducens nucleus.
Pathology The anatomic localization of the lesion in the one-and-a-half syndrome has been confirmed at autopsy in seven patients. Six of them had a single unilateral lesion in the pontine tegmentum ipsilateral to the gaze palsy involving the PPRF and the ipsilateral MLF. The abducens nucleus was spared by discrete lesions and involved in extensive lesions resulting from infarction, hemorrhage or glioma. In Fisher's case, extensive pontine infarction involved both the PPRF and the abducens nucleus. Crevits et al correlated the gaze palsy with a single discrete infarct 3 by 2 mm in diameter in the ipsilateral PPRF and MLF. The lower fascicles of the ipsilateral sixth nerve passed through the necrotic area. This was probably the smallest lesion associated with the one-and-a-half syndrome. Newman et al reported a similar clinical case, but they found an ipsilateral PPRF lesion and "ischemic necrosis in the region of the abducens nucleus, although individual neurons could be identified". Partial damage to the contralateral PPRF was also found. In another pathologically confirmed case evaluated clinically by electro-oculography, a hypertensive hemorrhage in the rostral pontine tegmentum had spread into the right basis pontis to destroy the ipsilateral PPRF and abducens nucleus.
Etiology Pontine hemorrhage
Disease/Diagnosis Pontine hemorrhage
References 1. Bennett H, Savill TH. A case of permanent conjugate deviation of the eyes and head, the result of a lesion limited to the sixth nucleus, with remarks on associated lateral movements of the eyeballs, and rotation of the head and neck. Brain 1889;12:102-116. 2. Bogousslavsky J, Miklossy J, Regli F, Deruaz JP, Despland PA. One-and-a-half syndrome in ischemic locked-in state. J Neurol Neurosurg Psychiatry 1984;47:927-935. 3. Carter JE, Rauch RA. One-and-a-half syndrome type II. arch Neurol 1994;51:87-80. 4. Cogan DG, Wray SH. Internuclear ophthalmoplegia as an early sign of brainstem tumor. Neurology 1970;20:629-633. 5. Crevits L, de Reuck J, vander Eecken H: Paralytic pontine exotropia in subarachnoid hemorrhage: a clinocopathological correlation. Clin Neurol Neurosurg 1975:78:269-276. 6. Fisher CM. Some neuro-ophthalmological observations. J Neurol Neurosurg Psychiatry 1967;30:383-392. 7. Jackel RA, Gittinger JW Jr, Smith TW, Passarelli CB. Metastatic adenocarcinoma presenting as a one-and-a-half syndrome. J Clin Neuroopthalmol 1986; 6:116-119. 8. Kataoka S, Hori A, Shirakawa T, Hirose G. Paramedian pontine infarction. Neurological/topographical correlation. Stroke 1997;28:809-815. 9. Miller NR, Biousse V, Hwang T, Patel S, Newman NJ, Zee DS. Isolated acquired unilateral horizontal gaze paresis from a putative lesion of the abducens nucleus. J Neuroophthalmol. 2002;3:204-207. 10. Müri RM, Chermann JF, Cohen L, Rivaud S, Pierrot-Deseilligny C. Ocular motor consequences of damage to the abducens nucleus area in humans. J Neuroophthalmol. 1996;Sep;16(3):191-195. 11. Newman NM, Day SH, Aguilar MJ. Paralytic pontine exotropia a case report with clinicopathologic confirmation. Augenbewegungastörungen Neurophysiologie und Klinik, München JF Bergman Verlag, 1978. 12. Newton HB, Miner ME. "One-and-a-half syndrome after resection of a midline cerebellar astrocytoma: case report and discussion of the literature. Neurosurgery 1991;29:768-772. 13. Oommen KJ, Smith MS, Labadie EL. Pontine hemorrhage causing Fisher one-and-a-half syndrome with facial paralysis. J Clin Neuroophthalmol 1982;2:129-132. 14. Pierrot-Deseilligny C, Chain F, Gray F, Escourolle R, Castaigne P. [Supranuclear lateral gaze palsy of pontine origin. Report of 2 clinicopathologic cases with electrooculographic and electromyographic data] Rev Neurol (Paris). 1979;135(11):741-762. 15. Raps EC, Galetta SL, King JT Jr, Yachnis AT, Flamm ES. Isolated one-and-a-half syndrome with pontine cavernous angioma; successful surgical removal. J Clin Neuroophthalmol 1990;10:287-290. 16. Sharpe JA, Rosenberg MA, Hoyt WF, Daroff RB. Paralytic pontine exotropia. A sign of acute unilateral pontine gaze palsy and internculear ophthalmoplegia. Neurology 1974;24:1076-1081. 17. Smith JL, Cogan DG. Internuclear ophthalmoplegia. A review of 58 cases. A.M.A. Arch Ophthalmol 1959;61:687-694. 18. Smith MS, Buchsbaum HW, Masland WS. One-and-a-half syndrome. Occurrence after trauma with computerized tomographic correlation. Arch Neurol 1980;37:251. 19. Wall M, Wray SH. The one-and-a-half syndrome: a unilateral lesion of the pontine tegmentum. A study of 20 cases and review of the literature. Neurology 1983, 33:971-980.
Relation is Part of 922-2, 941-4, 941-6
Contributor Secondary Ray Balhorn, Video Compressionist
Publisher Spencer S. Eccles Health Sciences Library, University of Utah
Date 1980
Type Image/MovingImage
Format video/mp4
Source 16 mm film
Rights Management Copyright 2002. For further information regarding the rights to this collection, please visit:
Holding Institution Spencer S. Eccles Health Sciences Library, University of Utah, 10 N 1900 E, SLC, UT 84112-5890
Collection Neuro-ophthalmology Virtual Education Library: NOVEL
Language eng
ARK ark:/87278/s6hb22tz
Setname ehsl_novel_shw
Date Created 2008-04-15
Date Modified 2021-05-06
ID 188619
Reference URL
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