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Show Journal of Neiiro- Ophthahnology 18( 1): 21- 24, 1998. © 1998 Lippincott- Ravcn Publishers, Philadelphia Follow- up Studies on Pattern Reversal Visually Evoked Cortical Potentials in a 2- Year- Old Child with Optic Neuritis Kimi Sato, M. D., Emiko Adachi- Usami, M. D., and Atsushi Mizota, M. D. A 2- year and 7- month- old boy had sudden visual loss in both eyes and showed bilateral optic neuritis without systemic symptoms. Steroid therapy improved his visual acuity from 0.077 and 0.053 to 1.0 at 7 months after onset. Magnetic resonance imaging ( MRI) of the brain showed high density in both optic nerves and multiple lesions in the white matter that were enhanced by gadolinium. We considered the diagnosis of de-myelinating disease. Follow- up MRI showed no abnormal lesion. Both transient and steady- state pattern visually evoked cortical potentials were nondetectable at the onset, and the PI00 component of the transient pattern reversed visually evoked cortical potential appeared to be delayed thereafter. It has since become shorter in parallel with visual acuity improvement. Key Words: Optic neuritis- Child- Pattern visually evoked cortical potentials. In children, optic neuritis often occurs in both eyes. Vaccination and infection commonly precede optic neuritis ( 1) and are associated with demyelinating diseases such as acute disseminated encephalomyelitis ( ADEM) and multiple sclerosis ( MS) ( 2). A search of the literature showed that the youngest patient reported was probably 3 years of age ( 3). Here we describe a 2- year and 7- month- old boy who showed bilateral papillitis with no systemic symptoms throughout treatment. Follow- up study of the patient included pattern reversal visually evoked cortical potentials ( PVECPs). CASE REPORT A 2- year and 7- month- old boy was referred to our clinic on April 25, 1995, because of sudden visual disturbance in both eyes. According to his parents, he complained that he could not see, and they noted that he looked blank and did not gaze at anything. He had vomited several times a few days before the parents noticed Manuscript received July 28, 1997. From the Department of Ophthalmology, Chiba University School of Medicine, Chiba, Japan. Address correspondence and reprint request to Dr. E. Adachi- Usami, Chiba University School of Medicine, Inohana 1- 8- 1, Chuo- ku, Chiba 260, Japan. his decreased vision. The patient's past medical history and family histories were noncontributory except that he received a measles vaccination on March 17. On examination, the primary position of his eyes was orthophoric, the diameter of the pupil was 2.5 mm in both eyes, and the pupillary response to light was poor. The optic disks were reddish and edematous with blurred margins in both eyes, and the retinal veins were extremely engorged. The altered vasculature was more pronounced on the right than on the left ( Fig. 1A). The patient was immediately admitted to the hospital and his systemic examination was performed by pediatricians. His general condition was good, and there were no abnormal neurologic signs. Laboratory test results, including a lumbar puncture, were within normal range. The titer of anticaludiolipic acid was nil. Studies for viral infection were negative. Magnetic resonance imaging ( MRI) of the brain demonstrated expanded high density at both optic nerves, and abnormal lesions of the white matter of the brain on T, were enhanced by gadolinium ( Fig. 2A, B). The patient cooperated for the measurement of both transient and steady- state ( PVECPs). The responses were nonrecord-able with each eye stimulation ( Fig. 3). Visual acuity was 0.077 in the right eye and 0.053 in the left eye by Teller acuity cards ( TACs). Because a demyelinating disease or an infectious disease was suspected, he was treated with intravenous prednisolone ( 2 mg/ kg) for 11 days. The high- density abnormal lesions seen on the MRI resolved at 7 weeks ( Fig. 4). Thereafter, the prednisolone was reduced. The P100 component of the transient PVECP was still delayed in both eyes. Twenty days after admission, his visual acuity recovered to 0.63 in the right eye and 0.32 in the left eye by TAC. The optic disk appeared to be normal in both eyes. Color vision test with the Okuma plates for children showed normal findings. Binocular vision test was normal. The PI00 component of the transient PVECP had become shorter as the visual acuity improved. However, the steady- state response has remained nonrecordable and nonreproducible. Throughout the admission, no neurologic sign was observed except optic neuritis. Five months after onset, his transient PVECP was normal in both eyes and his visual 21 22 K. SATO ET AL. FIG. 1. Fundus photographs taken 1 week after onset of visual disturbance. Both optic disks are swollen ( A). And those taken at the recovery stage ( B). acuity was 1.0 bilaterally. However, the steady- state VECP still remained abnormal. DISCUSSION To our knowledge, our patient represents the youngest patient with optic neuritis ever reported and one in which PVECPs could be recorded without the help of general anesthetic drugs. It is known that optic neuritis in children occurs bilaterally, and the papillitis appeared to resolve more quickly with steroid treatment ( 3,4). These clinical characteristics were similarly found in the present case. Frequently, affected children had flulike symptoms such as headache and nausea before onset. Although our patient showed no such symptoms, it was thought that he was too young to complain about them. If his parents could have observed his daily behavior more carefully, preceding symptoms may have been found. However, they were generally unexpected. We suspect that the cause of optic neuritis in our patient could have been ADEM, MS, or possibly vaccination. ADEM was not appropriate because the patient showed no systemic neurologic sign. Our patient did have a measles vaccination 5 weeks before the onset. Riikonen reported 18 children with optic neuritis after infection and vaccination ( 5). Their ages ranged from 5.2 to 14.5 years. The interval between the onset of optic neuritis and the last vaccination varied from 3 days to 10 years. In the author's study, 10 of 18 children developed MS. We will have to observe our patient long term to decide the cause conclusively. The transient PVECP in our patient recovered before . . . . • • : i i; • - • • • i. In: 1-) II i • •• . ' r - : . • . y 1 R r ; . - jn t U i li* n-iil Aii H Yi • (. lU'il ' J . t ip IMn!!*':- NI- : t l . ' l [ . / c: * t * m , ; ...... i J M J i l l | J t u1. j v. iu i i • i " ' . j hmkiiu 1 r • 1 Wfi i I'f B FIG. 2. T.,- weighted images ( A) and T.^ weighted Fat Sat images ( TR/ TE/ excitation: 500/ 14/ 2) with gadolinium injection ( B) demonstrated ringlike enhancement around the bilateral optic nerves, 4 days after onset. J Neuro- Ophlhalmol, Vol. 18, No. 1, 1998 OPTIC NEURITIS IN A 2- YEAR- OLD CHILD 23 1995 Apr. May May Jun. 25 9 26 12 transient pattern VECP OD OS 00 ms steady state pattern VECP FIG. 3. Transient pattern VECPs to three reversals per second ( A) and steady- state pattern VECPs to 12 reversals per second ( B) recorded from a patient with optic neuritis. Check size 16 min, contrast 80%, field size 7 x 1 1 degrees. OD OS 100 ms the steady- state PVECPs. If we consider the measuring difficulty between transient and steady- state PVECPs, transient PVECP is hardly performed in children. To isolate the PI00 component, reversal frequency needs to be much slower than for a steady- state response, which entails a long recording session for the subject. Our patient was very cooperative and produced good results. It has been known ( 6) that the PI00 component of the PVECP can be delayed significantly in patients with demyelin-ating diseases. Furthermore, this delay may be much longer than that found in optic neuritis from other etiologies ( 7). In our patient, there was a 15- ms delay of the PI00 between the value measured at the beginning of his visual recovery stage and that obtained at the almost recovered stage. The delay was shorter than the value found in patients with demyelinating diseases. The shortened P100 latency was clearly followed up and correlated with the subjective visual acuity. This feature was noteworthy because a 2- year and 7- month- old patient could hardly cooperate with PVECP testing. The shortened delay in such a child suggests that the cause of his papillitis was less likely to be a demyelinating disease than a vaccination. Despite the recovery of visual acuity, PI00 latency remained obviously delayed in patients with demyelinating diseases ( 6). However, we must continue to observe the patient because no such case has been available. J Neuro- Ophthalmol, Vol. IS, No. I, 1998 24 K. SATO ETAL. . ,..• 1.1.1 SaraM ! • ! 1 l " . V CCc ASM j i j TE: H.' Ff • 11 : 1 . ' L LEW 11 r c r. a. QUnk/ L.& i H.'( Vl; 4a . i-.'; ml.: , s i M • i i i £ ISQCO ^ % m ' V V 4 ^ Vi l^^| H iiirdA IBTV. ICTPITiL 1 1+ 53- l'l » J- U Ob/ I S /* w- 1 i I F L p . a • vl FIG. 4. T^ weighted images ( A) and " TVweighted Fat Sat images with gadolinium injection ( B) demonstrated no enhancement of the bilateral optic nerves, 7 weeks after onset. REFERENCES Charles K, Frank DC. Optic neuritis in children. Arch Ophthalmol 1960; 63: 747- 55. Brian DE, Gregory SK, Bruce HC. Medical and surgical management of acute disseminated encephalomyelitis. J Neuro- ophthalmol 1994; 14: 210- 3. Taylor D, Cuendet F. Optic neuritis in childhood. In: Hess RF, Rent GT, eds. Optic neuritis. Cambridge, England: Cambridge University Press, 1986: 73- 85. 4. Kriss A, Francis DA, Cuendet F, et al. Recovery after optic neuritis in childhood. J Neurol Neurosurg Psychiatry 1988; 51: 1253- 8. 5. Riikonen R. The role of infection and vaccination in the genesis of optic neuritis and multiple sclerosis in children. Acta Neurol Scand 1989; 80: 425- 31. 6. Halliday AM, McDonald WI, Mushin J. Visual evoked response in diagnosis of multiple sclerosis. Br Med J 1973; 4: 661- 4. 7. Halliday AM, McDonald WI, Mushin J. Delayed visual- evoked response in optic neuritis. Lancet 1972; 1: 982- 5. J Neuw- Ophthatmol, Vol. IS. No. I, 1998 |
