A case of superior cerebellar artery syndrome with contralateral hearing loss at onset
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《神经病学神经外科学杂志》
1 Department of Neurology, National Hospital Organization Okayama Medical Center, Okayama, Japan
2 Department of Neurology, Okayama University Graduate School of Medicine and Dentistry, Okayama, Japan
3 Department of Neurology, National Hospital Organization Okayama Medical Center, Okayama, Japan
4 Department of Neurology, Okayama University Graduate School of Medicine and Dentistry, Okayama, Japan
5 Department of Neurology, National Hospital Organization Okayama Medical Center, Okayama, Japan
Correspondence to:
Dr Tetsuro Murakami
Department of Neurology, Okayama University Graduate School of Medicine and Dentistry, 2-5-1 Shikata-cho, Okayama 700-8558, Japan; neuron@cc.okayama-u.ac.jp
Keywords: contralateral side; hearing loss; infarction; superior cerebellar artery
Deafness is rare in ischaemic stroke but sometimes occurs as a result of lower pons infarction. The main cause of such deafness is occlusion of the anterior inferior cerebellar artery (AICA); occlusion of the superior cerebellar artery (SCA), which perfuses the higher pons, causes SCA syndrome and also results in deafness but is extremely rare.1 In the present report, we describe a patient with SCA syndrome, whose initial complaint was contralateral hearing loss.
Case report
A 64 year old male with untreated hyperglycaemia and hypertension was admitted 4 h after the sudden onset of deafness in his right ear. Hearing loss was the only complaint and other neurological signs were absent. Right sensorineural hearing loss was revealed by a hearing test (fig 1A). After several examinations including stapedial reflexes and speech discrimination, an initial diagnosis of sudden deafness was made. However, 8 h later the patient complained of diplopia, vertigo, and nausea. Impaired abducens function in the right eye and bilateral lateral gaze nystagmus were observed. Finger-nose and heel-knee tests suggested left cerebellar ataxia. Hence, a diagnosis of SCA syndrome was made, and argatroban, an anti-coagulant, was administered. Diffusion weighted magnetic resonance imaging (MRI) 12 h after onset showed infarctions in the left cerebellum (fig 1B) and lateral superior pons (fig 1C). Magnetic resonance angiography showed loss of blood flow in the lower basilar artery (fig 1D). Respiratory failure developed 4 h later, and the next day the patient also showed right hemiparesis and Horner’s syndrome. Bilateral cortical blindness was also present. A diagnosis of SCA syndrome with hemiparesis and cortical blindness was made. A fluid attenuated inversion recovery (FLAIR) image 2 weeks later showed an enlarged infarction in the left cerebellum, and a new infarction in the right cerebellum, dorsal pons, and bilateral occipital lobes (fig 1E). The patient’s symptoms remained unchanged 3 months later.
Figure 1 (A) Right sensorineural hearing loss. "o" and "x" indicate air conduction without masking in the right and left ears, respectively. "" indicate bone conduction with masking in the right and left ears, respectively. (B, C) Axial diffusion weighted MRI images (B, C) 12 h after the onset of deafness. Note high signal intensity at the left cerebellum (B, arrow) and left lateral superior pons (C, arrow). (D) Magnetic resonance angiography showing occlusion of the lower basilar artery (arrows). (E) Axial FLAIR showing high intensity areas at both occipital lobes (arrows).
Discussion
SCA syndrome shows ipsilateral cerebellar ataxia and Horner’s syndrome, contralateral superficial sensory disturbance and hearing loss, as well as nystagmus toward the impaired side, vertigo, and nausea.2 Fibres from the contralateral auditory nucleus join the lateral lemniscus, pass into the brain, and terminate in the hearing centre. Therefore, impairment of the lateral lemniscus on one side causes hearing loss on the other. In SCA infarction, the ischaemic lesion occurs in the area where fibres from the nucleus have already crossed, and therefore sensory hearing loss is observed in the contralateral side.
We describe a rare case of SCA syndrome which began with deafness in one ear. Although deafness sometimes occurs as a result of brainstem infarction, most cases of ipsilateral hearing loss are due to AICA infarction.3 To our knowledge, the study by Doyle et al is the only previous report of hearing loss due to contralateral SCA infarction.1 Amarenco et al described a large series of SCA syndrome cases, where no patient showed contralateral deafness.4 The present report presents a important finding regarding symptoms of ischaemic stroke, and suggests that hearing loss, although rare, can be the first symptom. It is necessary to carefully observe patients with sudden deafness.
References
Doyle KJ, Fowler C, Starr A. Audiologic findings in unilateral deafness resulting from contralateral pontine infarct. Otolaryngol Head Neck Surg 1996;114:482–6.
Mills CK. Hemianesthesia to pain and temperature and loss of emotional expression on the right side, with ataxia of the upper limbs on the left. The symptoms probably due to a lesion of the thalamus or superior peduncles. J Nerv Ment Dis 1908;35:331–2.
Lee H, Sohn SI, Jung DK, et al. Sudden deafness and anterior inferior cerebellar artery infarction. Stroke 2002;33:2807–12.
Amarenco P, Hauw JJ. Cerebellar infarction in the territory of the superior cerebellar artery: a clinicopathologic study of 33 cases. Neurology 1990;40:1383–90.(T Murakami1, Y Ono1, N Ak)
2 Department of Neurology, Okayama University Graduate School of Medicine and Dentistry, Okayama, Japan
3 Department of Neurology, National Hospital Organization Okayama Medical Center, Okayama, Japan
4 Department of Neurology, Okayama University Graduate School of Medicine and Dentistry, Okayama, Japan
5 Department of Neurology, National Hospital Organization Okayama Medical Center, Okayama, Japan
Correspondence to:
Dr Tetsuro Murakami
Department of Neurology, Okayama University Graduate School of Medicine and Dentistry, 2-5-1 Shikata-cho, Okayama 700-8558, Japan; neuron@cc.okayama-u.ac.jp
Keywords: contralateral side; hearing loss; infarction; superior cerebellar artery
Deafness is rare in ischaemic stroke but sometimes occurs as a result of lower pons infarction. The main cause of such deafness is occlusion of the anterior inferior cerebellar artery (AICA); occlusion of the superior cerebellar artery (SCA), which perfuses the higher pons, causes SCA syndrome and also results in deafness but is extremely rare.1 In the present report, we describe a patient with SCA syndrome, whose initial complaint was contralateral hearing loss.
Case report
A 64 year old male with untreated hyperglycaemia and hypertension was admitted 4 h after the sudden onset of deafness in his right ear. Hearing loss was the only complaint and other neurological signs were absent. Right sensorineural hearing loss was revealed by a hearing test (fig 1A). After several examinations including stapedial reflexes and speech discrimination, an initial diagnosis of sudden deafness was made. However, 8 h later the patient complained of diplopia, vertigo, and nausea. Impaired abducens function in the right eye and bilateral lateral gaze nystagmus were observed. Finger-nose and heel-knee tests suggested left cerebellar ataxia. Hence, a diagnosis of SCA syndrome was made, and argatroban, an anti-coagulant, was administered. Diffusion weighted magnetic resonance imaging (MRI) 12 h after onset showed infarctions in the left cerebellum (fig 1B) and lateral superior pons (fig 1C). Magnetic resonance angiography showed loss of blood flow in the lower basilar artery (fig 1D). Respiratory failure developed 4 h later, and the next day the patient also showed right hemiparesis and Horner’s syndrome. Bilateral cortical blindness was also present. A diagnosis of SCA syndrome with hemiparesis and cortical blindness was made. A fluid attenuated inversion recovery (FLAIR) image 2 weeks later showed an enlarged infarction in the left cerebellum, and a new infarction in the right cerebellum, dorsal pons, and bilateral occipital lobes (fig 1E). The patient’s symptoms remained unchanged 3 months later.
Figure 1 (A) Right sensorineural hearing loss. "o" and "x" indicate air conduction without masking in the right and left ears, respectively. "" indicate bone conduction with masking in the right and left ears, respectively. (B, C) Axial diffusion weighted MRI images (B, C) 12 h after the onset of deafness. Note high signal intensity at the left cerebellum (B, arrow) and left lateral superior pons (C, arrow). (D) Magnetic resonance angiography showing occlusion of the lower basilar artery (arrows). (E) Axial FLAIR showing high intensity areas at both occipital lobes (arrows).
Discussion
SCA syndrome shows ipsilateral cerebellar ataxia and Horner’s syndrome, contralateral superficial sensory disturbance and hearing loss, as well as nystagmus toward the impaired side, vertigo, and nausea.2 Fibres from the contralateral auditory nucleus join the lateral lemniscus, pass into the brain, and terminate in the hearing centre. Therefore, impairment of the lateral lemniscus on one side causes hearing loss on the other. In SCA infarction, the ischaemic lesion occurs in the area where fibres from the nucleus have already crossed, and therefore sensory hearing loss is observed in the contralateral side.
We describe a rare case of SCA syndrome which began with deafness in one ear. Although deafness sometimes occurs as a result of brainstem infarction, most cases of ipsilateral hearing loss are due to AICA infarction.3 To our knowledge, the study by Doyle et al is the only previous report of hearing loss due to contralateral SCA infarction.1 Amarenco et al described a large series of SCA syndrome cases, where no patient showed contralateral deafness.4 The present report presents a important finding regarding symptoms of ischaemic stroke, and suggests that hearing loss, although rare, can be the first symptom. It is necessary to carefully observe patients with sudden deafness.
References
Doyle KJ, Fowler C, Starr A. Audiologic findings in unilateral deafness resulting from contralateral pontine infarct. Otolaryngol Head Neck Surg 1996;114:482–6.
Mills CK. Hemianesthesia to pain and temperature and loss of emotional expression on the right side, with ataxia of the upper limbs on the left. The symptoms probably due to a lesion of the thalamus or superior peduncles. J Nerv Ment Dis 1908;35:331–2.
Lee H, Sohn SI, Jung DK, et al. Sudden deafness and anterior inferior cerebellar artery infarction. Stroke 2002;33:2807–12.
Amarenco P, Hauw JJ. Cerebellar infarction in the territory of the superior cerebellar artery: a clinicopathologic study of 33 cases. Neurology 1990;40:1383–90.(T Murakami1, Y Ono1, N Ak)