| Identifier |
163-9-2 |
| Title |
Congenital Nystagmus; Latent Nystagmus |
| 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 |
Congenital Nystagmus; Horizontal Jerk Nystagmus; Optokinetic Nystagmus absent; Infantile Nystagmus Syndrome Latent Nystagmus; Fusional Maldevelopment Nystagmus Syndrome |
| History |
This little girl has had nystagmus since birth. She has the classical constellation of signs, initially diagnosed as congenital motor nystagmus with: • Horizontal jerk nystagmus • A slight head turn to the right to place the eyes in the null position • Latent nystagmus • Inability to superimpose optokinetic nystagmus even tested with the eyes in the null position of gaze Classification: The Classification of Eye Movement Abnormalities and Strabismus Working Group has recommended new names for nystagmus that begins during infancy. Three categories have been defined: 1. Infantile Nystagmus Syndrome (INS), which corresponds to what had previously been called motor or sensory forms of congenital nystagmus. 2. Fusional Maldevelopment Nystagmus Syndrome (FMNS), which corresponds to latent nystagmus occurring in association with amblyopia and strabismus and 3. Spasmus Nutans Syndrome (SNS). Diagnostic features of each of these syndromes are summarized in (ref 11). Box 10-11 Clinical features of Infantile Nystagmus Syndrome (See Chp 10, p513) Box 10-12 Clinical features of Latent Nystagmus (FMNS) (See Ch 10 p517) Box 10-13 Clinical features of Spasmus Nutans Syndrome (See Chp 10 p519) The congenital ‘nystagmus' of INS maybe present at birth but usually develops during infancy. Although variable in wave form (the commonest are increasing-velocity and pendular), certain clinical features usually differentiate INS from other ocular oscillations. • INS is almost always conjugate and mainly horizontal, even on up or downgaze. • A torsional component to the nystagmus is probably common but may be difficult to identify clinically. • Less commonly the nystagmus of INS is mainly seesaw and such patients may have underlying disease of the retina, visual pathways or cerebellum. • Life long nystagmus that is vertical is not typical of INS, and consideration should be given to other diagnoses such as the calcium channelopathies. • Nystagmus of INS is usually accentuated by the attempt to fixate on an object, and by attention or anxiety. • Eyelid closure or convergence, usually suppress it, but occasionally the nystagmus is evoked by viewing a near target. • Often nystagmus decreases when the eyes are moved into a particular position in the orbit; this is called the null point or zone, and corresponds to the range of eye position within which slow-phase eye velocity is at a minimum. • In some patients, especially albinos, the nystagmus periodically reverses direction, but this reversal seldom occurs in the regular manner seen in the acquired form of PAN. Stereovision: is usually degraded, even in children lacking strabismus, partly due to retinal image motion. Oscillopsia: Children with congenital nystagmus rarely complain of movement of visual images (oscillopsia). Head turns: Head turns are common in INS and are used to bring the eye and the orbit close to the null point or zone, which nystagmus is minimal. The presence of such head turns in childhood photographs is often useful evidence in diagnosing INS. Nystagmus blockage syndrome: Another strategy used by patients with either INS or the latent nystagmus of FMNS is to purposely induce an esotropia (nystagmus blockage syndrome) in order to suppress the nystagmus; such an esotropia requires a head turn to direct the viewing eye at the object of interest. Head oscillations: Some patients with INS also show head oscillations. Such head movements are not compensatory and tend to increase when the individual attends to an object, an effort that also increases the nystagmus. It seems possible, therefore, that in most patients head tremor and ocular oscillations represent the output of a common neural mechanism. Associated visual system defects: Overall, most children with congenital forms of nystagmus have no associated visual system defects. (See Table 10-7 Visual system disorders associated with INS Chp 10 p513. (ref 11)). Familial INS: INS either, with or without associated visual system abnormalities may be familial. Autosomal dominant, and sex-linked recessive forms of inheritance have been reported. In x-linked forms, the mother may show subtle ocular motor abnormalities. The hereditary forms of INS, with the characteristic wave forms should be differentiated from other genetic disorders that produce forms of nystagmus typical of cerebellar dysfunction. Latent Nystagmus: Cogan described latent nystagmus in his book, Neurology of the Ocular Muscles, 2nd Edition, Charles C. Thomas Publisher, 1956, as follows: Latent nystagmus is a jerk type of nystagmus that is brought out by covering one eye. When both eyes are open and a clear image is present in both eyes, no nystagmus is present but covering one eye, blurring the image of one eye, or reducing the image brightness in one eye results in a conjugate nystagmus made up of a slow drift of the eyes toward the side of the covered eye, with a fast corrective phase toward the side of the open eye. The nystagmus is least when the gaze is directed toward the side of the covered eye and greatest when the gaze is directed toward the side of the open eye. It is usually present bilaterally, but cases have been reported in which it is elicited on the covering of one eye only. Contrary to the general impression, it is not the disruption of binocular fixation that gives rise to the nystagmus, since it is frequently seen in patients with strabismus and a 15 degree prism placed before one eye so as to produce vertical diplopia does not necessarily cause nystagmus. Furthermore, the nystagmus may be brought out merely by shining a bright light in one eye, and the resultant nystagmus is in the same direction as though the eye were being covered. Thus, it appears that latent nystagmus is brought about by making the image brightness or distinctness in the two eyes unequal rather than simply by disrupting binocular fixation. Latent nystagmus is typically horizontal and is usually not accompanied by other abnormalities, although strabismus, monocular amblyopia, and so-called alternating hyperphoria have been reported with it. Loss of one eye in patients with latent nystagmus results in nystagmus of the other eye either permanent or with periodic spontaneous recurrences. Etiology: Latent nystagmus is one form of Fusional Maldevelopment Nystagmus Syndrome (FMNS). Affected patients usually have: • Strabismus, typically esotropia • Amblyopia is frequent • Normal stereopsis is rare Occasionally, congenital nystagmus (INS) and latent nystagmus co-exist. (ID 907-2) Latent nystagmus can be induced experimentally in monkeys either by depriving them of binocular vision early in life or by surgically creating strabismus. Latent nystagmus occurs in some, but not all patients, who have congenital uni-ocular visual loss, suggesting that additional factors beyond visual deprivation are responsible for the development of nystagmus. |
| Disease/Diagnosis |
Infantile Nystagmus Syndrome |
| Clinical |
This little girl has: • Very small amplitude conjugate horizontal jerk nystagmus in primary gaze • Slight head turn to the right • Latent nystagmus most evident on covering the right eye showing the quick phase of the nystagmus in the left eye beating away from the covered eye Covering the left eye shows a smaller amplitude latent nystagmus in the right eye with the quick phase beating away from the covered eye. Critiquing my own demonstration of this case, I would advise covering the eye for a longer period of time and not change the patch so quickly from eye to eye as you see in this tape. Comment: This case is a good example of true latent nystagmus with almost absent jerk nystagmus when both eyes are viewing. In some patients, like this child, latent nystagmus is present when one eye is covered but absent or of smaller amplitude when the other eye is occluded. True latent nystagmus is rare and in most patients nystagmus, which may be of low amplitude, is present when both eyes are uncovered, termed manifest latent nystagmus. |
| Presenting Symptom |
Nystagmus |
| Ocular Movements |
Congenital Nystagmus; Horizontal Jerk Nystagmus; Optokinetic Nystagmus Absent; Infantile Nystagmus Syndrome; Latent Nystagmus ; Fusional Maldevelopment Nystagmus Syndrome |
| Treatment |
Surgical procedures for congenital nystagmus are discussed in ref 11. |
| Etiology |
Congenital |
| Date |
1972 |
| References |
1. Abadi RV, Dickinson CM. Waveform characteristics in congenital nystagmus. Documents Ophthalmologica 1986;64:153-167. http://www.ncbi.nlm.nih.gov/pubmed/3608756 2. Abel, L.A., Wang, Z.I. and Dell'Osso, L.F.: Wavelet Analysis in Infantile Nystagmus Syndrome: Limitations and Abilities. Invest. Ophthalmol. Vis. Sci. 2008. (In Press). http://www.ncbi.nlm.nih.gov/pubmed/18450585 3. Averbuch-Heller L, Dell'Osso LF, Leigh RJ, Jacobs JB, Stahl JS. The torsional component of ‘horizontal' congenital nystagmus. J Neuro-ophthalmol 2002;22:22-32. http://www.ncbi.nlm.nih.gov/pubmed/11937902 4. Classification of Eye Movement Abnormalities andStrabismus (CEMAS) Working Group. http://www.nei.nih.gove/news/statements/cemas 2003. 5. Cogan D. Neurology of the Ocular Muscles, 2nd Edition. Charles C. Thomas Publisher, Springfield, Ill. 1956. 6. Dell'Osso LF, Traccis S, Abel LA. Strabismus: a necessary condition for latent and manifest latent nystagmus. Neuroophthalmol 1983;3:247-257. 7. Gresty MA, Metcalfe T, Timms C, Elston J, Lee J, Liu C. Neurology of latent nystagmus. Brain 1992;115:1303-1321. http://www.ncbi.nlm.nih.gov/pubmed/1422790 8. Hertle RW, Maldanado VK, Maybodi M, Yang D. Clinical and ocular motor analysis of the infantile nystagmus syndrome in the first 6 months of life. Br J Ophthalmol 2002;86:670-675. http://www.ncbi.nlm.nih.gov/pubmed/12034691 9. Hertle RW, Maybodi M, Mellow SD, Yang D. Clinical and oculographic response to Tenuate Dospan (diethylpropionate) in a patient with congenital nystagmus. Am J Ophthalmol 2002;133:159-160. http://www.ncbi.nlm.nih.gov/pubmed/11755862 10. Kushner BJ. Infantile uniocular blindness with bilateral nystagmus. A syndrome. Arch Ophthalmol 1995;113:1298-1300. http://www.ncbi.nlm.nih.gov/pubmed/7575263 11. Leigh JR, Zee DS. Diagnosis of Nystagmus and Saccadic Instrusions. Chp 10; 475-558. In: The Neurology of Eye Movements, Fourth Edition. Oxford University Press, NY 2006. 12. Shibasaki H, Motomura S. Suppression of congenital nystagmus. J Neurol Neurosurg Psychiatry 1978;41:1078-1083. http://www.ncbi.nlm.nih.gov/pubmed/731252 13. Stevens DJ, Hertle RW. Relationships between visual acuity and anomalous head posture in patients with congenital nystagmus. J Pediatr Ophthalmol Strabismus 2003;40:259-264. http://www.ncbi.nlm.nih.gov/pubmed/14560831 14. Tusa RJ, Mustari MJ, Das VE, Boothe RG. Animal models for visual deprivation-induced strabismus and nystagmus. Ann NY Acad Sci 2002;956:346-360. http://www.ncbi.nlm.nih.gov/pubmed/11960818 |
| Language |
eng |
| Format |
video/mp4 |
| Type |
Image/MovingImage |
| Source |
16 mm Film |
| Relation is Part of |
163-9-1, 163-9-3, 163-9-4, 169-28, 907-2, 936-6, 938-4, 944-8 |
| 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/s6gj2fjp |
| Setname |
ehsl_novel_shw |
| ID |
188596 |
| Reference URL |
https://collections.lib.utah.edu/ark:/87278/s6gj2fjp |
