Spasm of Accommodation Associated with Closed Head Trauma

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Spasm of Accommodation Associated with Closed Head Trauma ORIGINAL CONTRIBUTION Spasm of Accommodation Associated with Closed Head Trauma R. V. Paul Chan, MD Jonathan D. Trobe, MD Abstract: Spasm of accommodation, creating pseudo- from 1986 to 2000. Six patients met the criteria of (1) ante­ myopia, is generally associated with miosis and excess con­ cedent severe traumatic brain injury, (2) complaint of vergence as part of spasm of the near reflex. It may also blurred vision, and (3) 1.00 diopter or more of myopia exist as an isolated entity, usually attributed to psychogenic found on manifest than on cycloplegic refraction. The se­ causes. We present six cases of accommodative spasm as­ verity of the head injuries was based on coma for at least 1 sociated with closed head injury. All patients were male, week, elevated intracranial pressure, and neurologic find­ ranging in age between 16 and 37 years. The degree of ings consistent with brain stem and cerebral hemispheric pseudomyopia, defined as the difference between manifest damage. However, patients recovered enough to be aware and cycloplegic refraction, was 1.5 to 2 diopters. A 3-year that their vision was blurred for distance viewing. Cognitive trial of pharmacologically induced cycloplegia in one pa­ function was sufficiently intact to allow accurate measure­ tient did not lead to reversal of the spasm when the cy­ ment of visual function. cloplegia was stopped. All patients required the manifest refraction to see clearly at distance. The pseudomyopia en­ dured for at least 7 years following head trauma. This phe­ nomenon may represent traumatic activation or disinhibi- RESULTS tion of putative brain stem accommodation centers in young Our six patients were male and ranged in age between individuals. 16 and 37 years. All complained of reduced distance vision. Post-traumatic pseudomyopia ranged from 1.50 to 2.00 (JNeuro-Ophthalmol 2002;22: 15-17) diopters. Because the ophthalmologic examinations per­ formed prior to our consultations had not included cy­ pasm of accommodation, creating pseudomyopia, typi­ cloplegic refractions, the pseudomyopia had not been rec­ Scally occurs in conjunction with miosis and inappropri­ ognized. The visual complaints were vaguely attributed to ate convergence as part of spasm of the near reflex, usually consequences of brain injury. The single patient (case 4) triggered by anxiety, depression, or malingering (1,2). In who was managed with long-term pharmacologic cyclople­ this setting, and rarely after head trauma (4), spasm of ac­ gia did not show any resolution of the pseudomyopia when commodation may also occur without the other two com­ the cycloplegia was discontinued 3 years later. Pupils in ponents of the near reflex (4). We describe six new cases of dim illumination ranged in size between 3 and 6 mm, were post-traumatic accommodative spasm that did not manifest equal in size, and constricted normally to direct light. Al­ miosis or esotropia. In these cases, the complaint of blurred though eye movement abnormalities were present in all distance vision, which was readily rectified with glasses, three patients, none had ocular misalignment at distance was initially attributed to other neuro-ophthalmic conse­ (Table 1). quences of head trauma. METHODS We retrieved the cases by searching the files of the DISCUSSION Neuro-ophthalmology Clinic, University of Michigan, This case series affirms that spasm of accommoda­ tion, without other components of the near reflex, may oc­ cur following severe brain stem injury in young adults. The The Departments of Ophthalmology (Kellogg Eye Center) and Neu­ fact that this phenomenon has been so infrequently reported rology, University of Michigan Medical Center, Ann Arbor, Michigan, USA. suggests that it is rare. However, it may also be overlooked, Address correspondence to Jonathan D. Trobe, MD, Kellogg Eye Cen­ because debilitated patients are unable to clearly articulate ter, 1000 Wall Street, Ann Arbor, MI 48105, USA their complaints. J Neuro-Ophthalmol, Vol. 22, No. 1, 2002 15 Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. JNeuro-Ophthalmol, Vol. 22, No. 1, 2002 Chan and Trobe TABLE 1. Patient characteristics Patient Age, y/ Neurologic (case #) gender Date/type of accident Imaging abnormalities 1 30/male 5/1/96/fall from a roof; coma x 1 CT: left frontal and parietal lobe 10/1999: left greater than right week hemorrhages hemiparesis 2 20/male 1/1990/rollover accident; coma CT: multiple contusions of both 9/1991: dystonic left hemiparesis x 2 weeks frontal lobes and the brain stem; subarachnoid hemorrhage 18/male 8/1999/two-car collision; coma CT: subarachnoid and frontal 11/1998: cognitive impairment, x 1 week lobe hemorrhage limb and gait ataxia 17/male 2/1986/two-car collision; coma Information not available 6/1987: spastic right hemiparesis x 2 weeks 16/male 1988/hit by car while on bicycle; CT: frontal and temporal lobe 5/1989: anosmia, gait ataxia coma x 1 week hemorrhages 37/male 1993/assaulted, hit on head with CT: parieto-occipital skull 8/2000: cognitive deficits, lead pipe; coma x 2 weeks fracture; frontal hemorrhages speech, extremity and gait ataxia The mechanism of the accommodative spasm is un­ linkage of the mechanisms involved in excess and deficient certain. In cats, accommodation is mediated by a pathway accommodation in brain stem damage. For example, some from the lateral suprasylvian cortex bilaterally to the ocular lesions may interfere with inhibition, while others interfere motor nuclei (5). Stimulation of this area also produces con­ with activation of the accommodative portion of the para­ vergence and miosis, but accommodation may be selec­ sympathetic (Edinger-Westphal) subnucleus of the third tively activated (5). Experimental accommodative spasm cranial nerve. Accommodative spasm tends to occur in has not been demonstrated. young individuals, perhaps because they have such strong Although overactive accommodation appears to be accommodative reserve. uncommon in brain lesions, accommodative paresis is not. Based on our cases, and those previously reported, It has been reported in Wilson disease, encephalitis, and left post-traumatic accommodative spasm appears to be an en­ parietal infarct or hematoma (6). Among patients with le­ during phenomenon. In our single patient (case 4) who un­ sions of the dorsal midbrain, accommodative paresis may derwent a 3-year trial of pharmacologic cycloplegia, the ac­ alternate with accommodative spasm (6). This suggests a commodative spasm did not disappear when the medication 16 © 2002 Lippincott Williams & Wilkins Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. SPASM OF ACCOMMODAHON ASSOCIATED WITH CLOSED HEAD TRAUMA JNeuro-Ophthalmol, Vol. 22, No. 1, 2002 TABLE 1. Patient characteristics (Continued) Pre-accident Post-accident Post-accident Other ophthalmic refraction manifest refraction cycloplegic refraction findings Treatment Information not 10/1999: 10/1999: 10/1999: 10/1999: available OD-1.50 OD Piano saccadic pursuit, manifest refraction OS:-1.50 OS Piano dysmetric eye (provided 20/20 OU) movements OD-3.25 9/1991: 9/1991: 9/1991: 9/1991: OS -3.25 -5.00 OU -3.25 OU saccadic pursuit, manifest refraction comitant (provided 20/20 OU) esotropia Information not 3/2000: 3/2000: 11/1998: 3/2000: available OD -2.25 + 0.75 OD-9.75+ 1.50 rotary nystagmus prescribed cycloplegic x003 x 180 refraction without OS-3.00 +0.50 x 174 OS-1.00 +1.25 x 160 cycloplegia 5/2000: 5/2000: 5/2000: OD:-2.00+ 1.00 OD-0.75+ 1.00 patient could only see x 180 x 180 20/50 with cycloplegic OS-3.50 +0.50 x 180 OS-1.00 +1.00 x 160 refraction; prescribed manifest refraction (20/20 OU) OD -0.50 2/1987: 2/1987: 6/1987: 6/1987: OS -0.50 OD -2.50 -0.50 x 10 OD-1.00-0.25 x 10 saccadic pursuit, homatropine and bifocals OS -2.50 OS-0.75-0.25 x 150 hypometric saccades 4/1990: 4/1990: 6/1987: patient could only see -2.50 OU OD-1.25 20/50 with cycloplegic OS-1.00 refraction; prescribed manifest refraction (20/20 OU) Information not 5/1990: 5/1990: 5/1989: none 5/1989: available OD -2.00 OD-1.25 prescribed manifest OS -2.00 + 0.75 x 145 OS-1.25 +0.75 x 145 refraction (20/20 OU) Information not 9/1997: 8/2000: 8/2000: 9/1997: available 1.75 OU saccadic pursuit saccadic pursuit prescribed full manifest 8/2000: refraction (20/20 OU) -1.75 OU Griffin JF, Wray SH, Anderson DP. Misdiagnosis of spasm of the was discontinued. In a previously reported case (3), it was near reflex. Neurology 1976;26:1018-20. still present after 6 years of topical atropine treatment. We Bohlmann BJ, France TD. Persistent accommodative spasm nine suggest that patients be fitted with their full manifest cor­ years after head trauma. J Clin Neuroophthalmol 1987;7:129-34. Sloane AE, Kraut JA. Spasm of accommodation. Doc Ophthalmol rection, together with a reading aid if necessary. 1973;34:365-9. Bando T, Takagi M, Toda H, Yoshizawa T. Functional roles of the lateral suprasylvian cortex in ocular near response in the cat. Neu- rosciRes 1992;15:162-78. Thompson HS, Miller NR. Disorders of Pupillary Function, Ac­ REFERENCES commodation, and Lacrimation. In: Miller NR, Newman NJ, eds. 1. Cogan DG, Freese CG. Spasm of the near reflex. Arch Ophthalmol Walsh &Hoyt's Clinical 1\'euro-ophthalmology: 5th ed. Vol. 1. Bal­ 1955:54:752-9. timore: Williams & Wilkins. 1998:1011-18. 17 Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. .
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