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A Case of Internuclear Ophthalmoplegia with Transient Rotatory Nystagmus in Facial Colliculus Infarction

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A Case of Internuclear Ophthalmoplegia with Transient Rotatory Nystagmus in Facial Colliculus Infarction CASE REPORT online © ML Comm J Neurocrit Care 2011;4:11-13 ISSN 2005-0348 A Case of Internuclear Ophthalmoplegia with Transient Rotatory Nystagmus in Facial Colliculus Infarction Sook Young Roh, MD1, Hyun Jeung Yu, MD1, Ku Eun Lee, MD1, Hyun Seok Kang, MD1, Hyun Kyung Kil, MD2 and Yoon Hee Kim, MD3 1Departments of Neurology, 2Opththalmology, 3Neuroradiology, Bundang Jesaeng General Hospital, Seongnam, Korea Background: Although internuclear ophthalmoplegia (INO) is a definite sign of an intrapontine or mesencephalic lesion, INO is rarely as- sociated with rotatory nystagmus in pontine lesions. We experienced a case of INO with transient rotatory nystagmus in facial colliculus infarction. Case Report: An 83-year-old male patient was admitted for acute vertical diplopia. Neurological examination revealed bilateral INO with transient ipsiversive rotatory nystagmus and ipsilateral peripheral type facial palsy. Diffusion weighted image revealed focal in- farction in the right facial colliculus. Ocular symptoms were improved within one month. Conclusion: We report a case of bilateral INO with transient rotatory nystagmus in right facial colliculus infarction. J Neurocrit Care 2011;4:11-13 KEY WORDS: Internuclear ophthalmoplegia · Transient rotatory nystagmus · Facial colliculus infarction. Introduction dL, and Hb A1c was 9.8%. Ocular examination showed bila- teral pupils of normal size with prompt direct light reflexes. A lesion of the medial longitudinal fasciculus (MLF) re- But bilateral adduction palsy with normal convergence, right- sults in an ipsilateral adduction deficit, and a contralateral ward gaze limitation with clockwise rotatory nystagmus in the abducting nystagmus and is often called internuclear ophth- right eye and horizontal nystagmus in the left eye on leftward almoplegia (INO).1 The interneurons of the MLF are intermix- gaze were observed (Fig. 1). Right peripheral type facial palsy ed with the abducens neurons in the sixth-nerve nucleus, wh- was also present. No other neurologic abnormalities were not- ich lies dorsally in the pons near the genu of the seventh crani- ed, and skew deviation and head tilting were not observed. On al nerve. A lesion in the facial colliculus produces a combin- the first day of admission, diffusion weighted image showed ation of INO and peripheral facial palsy. However, INO acute focal infarction in the right lower pons with restricted associated with rotatory nystagmus is rare in pontine lesions diffusion on the apparent diffusion coefficient map and cor- and only a few cases have been reported in the literature.2-5 responding high signal intensity on T2 weighted image/fluid- Here we reported a case of INO with transient rotatory nys- attenuated inversion recovery imaging (Fig. 2). He was pre- tagmus accompanied by peripheral facial palsy in facial col- scribed a regimen of aspirin and glimepiride. The bilateral liculus infarction. INO with ipsiversive rotatory nystagmus had resolved on the sixth day after symptom onset. The ipsilateral lateral gaze Case Report limitation and peripheral facial palsy persisted for one month (Fig. 3). An 83-year-old male patient with hypertension and diabe- tes mellitus was admitted to our neurology department due to Discussion vertical diplopia that had developed suddenly. His initial blo- od pressure was 145/65 mm Hg, blood glucose was 175 mg/ INO has diagnostic value in determining the site of the le- sion. The pontine center for lateral eye movement regulates Address for correspondence: Sook Young Roh, MD lateral gaze via innervation of the ipsilesional lateral rectus Department of Neurology, Pundang Jesaeng General Hospital, 255-2 Seohyon-dong, Bundang-gu, Seongnam 463-050, Korea muscle and the contralesional medial rectus through the MLF. Tel: +82-31-779-0879, Fax: +82-31-779-0879 Unilateral lesions of the MLF between the midpons and the E-mail: [email protected] oculomotor nucleus disconnect the ipsilateral medial rectus Copyright © 2011 The Korean Neurocritical Care Society 11 J Neurocrit Care ▌2011 ;4:11-13 FIGURE 1. Ocular examination sh- ows bilateral medial gaze limitations. MLF 4th ventricle Facial colliculus Superior cerebellar peduncle Vestibular nuclei Inferior cerebellar peduncle Reticular formation Spinal tract and nucleus of Middle cerebellar peduncle trigeminal nerve Medial leminiscus Trapezoid body Transverse pontine fibers Facial nerve (7) Bundles of corticospinal and corticonucler fibers FIGURE 3. Anatomic localization of Abducent nerve (6) Groove for basillar artery the patient in axial section through the pons at the level of facial colliculus. are usually located in the MLF above the level of the abducens nucleus and below the level of the trochlear nucleus. An MLF lesion could inactivate the interstitial nucleus of Cajal (INC). The INC is the integrator for ipsiversive rotatory movements and is situated between the red nucleus and the superior collic- ulus. The INC receives excitatory inputs from the vertical semicircular canals of the contralateral labyrinth via the MLF. Projections from the vestibular nuclei or vestibulocerebellum to the INC coordinate torsional gaze. It has been suggested FIGURE 2. Brain MRI findings on the first day of admission. The axial that INC inactivation produces contralesional torsional devia- diffusion weighted image and fluid-attenuated inversion recovery im- tion and rotatory ipsilesional nystagmus.10 MRI of our patient age shows focal high sinal intensity in the right facial colliculus (arrow). revealed a focal infarction in the right dorsomedial portion of subnucleus, causing adduction failure during horizontal gaze. the pontine tegmentum. There were no lesions in the vestibu- These ocular findings associated with abduction nystagmus of lar nuclei or INC. His bilateral adduction gaze palsy and rota- the contralateral eye are collectively referred to as INO. INO tory nystagmus resolved within one week. We suspect that a is frequently accompanied by a variety of other neurologic de- small facial colliculus lesion involving the MLF may have ficits due to extension of the MLF lesion into adjacent brain- been responsible for the inactivation of the ipsilateral vertical stem structures. A lesion that involves the sixth-nerve nucleus, integrator (the INC), producing INO associated with a tran- facial nerve fibers and the interneurons of the MLF near the sient ipsiversive rotatory nystagmus. In contrast, his ipsilateral facial colliculus produces the combination of ipsilateral ad- lateral gaze limitation and peripheral facial palsy were re- duction palcy, abduction limitation and peripheral facial palsy mained for one month. It may result from involvement of the in INO.6-8 However, INO is rarely associated with rotatory nys- abducens nerve nucleus and facial nerve fibers. tagmus.9 Lesions responsible for rotatory nystagmus with INO 12 A Case of Internuclear Ophthalmoplegia with Transient Rotatory Nystagmus in Facial Colliculus Infarction ▌SY Roh, et al. REFERENCES 6. Anderson CA, Sandberg E, Filley CM, Harris SL, Tyler KL. One and one-half syndrome with supranuclear facial weakness: magnetic res- 1. Gonyea EF. Bilateral internuclear ophthalmoplegia. Association with onance imaging localization. Arch Neurol 1999;56:1509-11. occlusive cerebrovascular disease. Arch Neurol 1974;31:163-73. 7. Jeong JL, Yi MJ, Kim YJ, Kim HS, Yang HD. Unilateral horizontal 2. Marshall RS, Sacco RL, Kreuger R, Odel JG, Mohr JP. Dissociated gaze paresis without facial palsy from a lesion of the abducens nucle- vertical nystagmus and internuclear ophthalmoplegia from a mid- us. J Korean Neurol Assoc 2009;27:449. brain infarction. Arch Neurol 1991;48:1304-5. 8. Park SW. Medial longitudinal fasciculus syndrome with ipsilateral 3. Nozaki S, Mukuno K, Ishikawa S. Internuclear ophthalmoplegia as- peripheral facial palsy:7 and 1/2 syndrome. Korean J Stroke 2010;12: sociated with ipsilateral downbeat nystagmus and contralateral incy- 119-20. clorotatory nystagmus. Ophthalmologica 1983;187:210-6. 9. Bae JS, Song HK, Kim CH, Choi IL, Lee JH, Lee BC. Fifteen-and-a- 4. Dehaene I, Casselman JW, D’Hooghe M, Van Zandijcke M. Unilater- half syndrome?: one-and-a-half syndrome with facial diplopia. Kore- al internuclear ophthalmoplegia and ipsiversive torsional nystagmus. an J Stroke 2002;4:151-3. J Neurol 1996;243:461-4. 10. Halmagyi GM, Aw ST, Dehaene I, Curthoys IS, Todd MJ. Jerk-wave- 5. Noseworthy JH, Ebers GC, Leigh RJ, Dell’Osso LF. Torsional nys- form see-saw nystagmus due to unilateral meso-diencephalic lesion. tagmus: quantitative features and possible pathogenesis. Neurology Brain 1994;117:789-803. 1988;38:992-4. 13.
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