A Case of Vertebrobasilar Insufficiency with Spontaneous Downbeat Nystagmus

Four cases of vertebrobasilar insufficiency are reported. Case 1 was a 38-year-old man who felt a sudden onset of dizziness when he turned his head to the back. An abnormal positional nystagmus was observed when he rotated his head to the left. A magnetic resonance angiogram (MRA) demonstrated total occlusion of the left vertebral artery (VA). Case 2 was a 31-year-old woman who had a total occlusion of her left VA as observed in the MRA. Case 3 was a 68-year-old man who noted dizziness. The systolic blood pressure change on his Schellong test was 28 mmHg. On his MRA, severe displacement of the basilar and the vertebral arteries was visible. Case 4 was a 76-year-old woman who noted a blackout-like sensation. Optokinetic nystagmus was noted with a hyponystagmus pattern, and an eye tracking test showed a saccadic pattern. On her MRA, the vertebrobasilar system was narrowed. The arterial architecture and any stenosis of the blood vessels could be detected non-invasively by MRA.

A Case of Infratentorial Meningioma Causing Spontaneous Downbeat Nystagmus: Case Report and Review of the Literature

Spontaneous Downbeat Nystagmus in Two Sisters with Sudanophilic Leukodystrophy

There have been, to our knowledge, only two previous reports of spontaneous downbeat nystagmus (SDN) in association with alcoholic cerebellar degeneration (ACD). 1,2 Spontaneous downbeat nystagmus is localizing to the craniocervical junction and the caudal midline cerebellum, 1,3 whereas ACD is highly localizing to the rostral midline cerebellum. 4 We now report an additional case of SDN in a patient with computed tomographic (CT) and clinical evidence of ACD. REPORT OF A CASE A 50-year-old former electrician was disabled by unsteadiness of gait. Records revealed that he had drunk heavily since age 16 years and that he had suffered numerous, serious injuries from falls. Initially, thiamine hydrochloride administration had improved his symptoms. A CT scan five years earlier had demonstrated enlargement of the fourth ventricle and mild cerebellar atrophy. At examination he denied oscillopsia or blurring of vision during rapid head movements. The patient was not visibly malnourished. There was

Downbeat nystagmus (DBN) is a rare neurological disorder characterized by slow upward drifts and fast downward phases [1]. In most cases no anatomical lesion is identified, whereas Arnold-Chiari malformation or spinocerebellar degeneration may underlie this condition [1]. AntiNMDAR (N-methyl-D-aspartate receptor) encephalitis rarely causes DBN [2]. Recently, we observed a young lady showing DBN as the sole initial manifestation. A 21-year-old lady presented with the 5-day history of dizziness that worsened gradually. On examination she had spontaneous DBN, which was occasionally overlapped with ocular flutter-like movement. Smooth pursuit was slightly saccadic, and during horizontal gaze horizontal nystagmus overlapped DBN. Eye movements were otherwise intact. She had no intentional tremor or dysmetria on finger-to-nose and heel-to-shin testing. However, her gait was wide-based and mildly unsteady. The remainder of her examination was normal. However, 4 days later, emotional lability and delirium manifested, gradually followed by involuntary movement (crawl swimming-like, myoclonic), mutism, and hyperpnea/apnea that eventually required mechanical ventilation (Fig. 1). Brain magnetic resonance imaging (MRI) on the admission day showed normal findings throughout the course of disease. Single-photon emission computed tomography (SPECT) on the third day showed decrease cerebral perfusion in the medial frontal cortex. An electroencephalography (EEG) was normal. Routine blood studies showed no abnormalities. Cerebrospinal fluid (CSF) analysis showed mildly increased cell count of 35/mm (mononuclear:polymorphonuclear = 32:3) and normal total protein. Viral antigens were all negative. Although survey for malignancies including ovary and paraneoplastic antibodies including anti-Hu, anti-Yo and anti-GAD was negative, she was suspected to have autoimmune encephalitis. Steroid pulse and high-dose intravenous immunoglobulin (IVIG) therapy was of limited benefit. However, anti-NMDAR antibodies in CSF appeared to be increased significantly. From the 37th day she underwent plasmapheresis, which ameliorated significantly her involuntary movement and mildly her level of consciousness. Repeated CT scans of the pelvis showed a 1.5 cm ovarian mass. On the 69th day she underwent tumor resection, which revealed a 14 mm * 13 mm mature teratoma. This surgery brought her to normal consciousness. Previously, DBN has been seldom reported in paraneoplastic encephalitis except for anti-Ma2 antibody encephalitis (one case) [3], anti-glutamate acid decarboxilase (GAD) antibody encephalitis (one case) [4], and anti-NMDAR encephalitis (one case) with upbeat nystagmus at the plateau stage under mechanical ventilation [2]. Our patient was unique in that she presented with DBN and dizziness as the sole initial manifestation. Experimental and functional neuroimaging studies indicated that DBN is caused by dysfunction of the vestibulocerebellum (flocculus, nodulus of cerebellar vermis) and, rarely, bilateral paramedian brainstem [1]. Although brainstem and cerebellum are not commonly Y. Tsuyusaki R. Sakakibara (&) M. Kishi F. Tateno Neurology, Internal Medicine, Sakura Medical Center, Toho University, 564-1 Shimoshizu, Sakura 285-8741, Japan e-mail: sakakibara@sakura.med.toho-u.ac.jp

Spontaneous downbeat nystagmus as a clue for the diagnosis of ataxia associated with anti-GAD antibodies

BackgroundLow-grade gangliogliomas (GGs) are typically epileptogenic intracranial neoplasms. Yet, the presentation of simplex vertiginous experience and spontaneous downbeat nystagmus (DBN) has not been reported to date.Case presentationWe present the case of a 26-year-old male with focal onset impaired awareness seizures, characterized by vertigo due to right temporal lobe epilepsy caused by ganglioglioma. As rare presentations, a spontaneous, consistent DBN in the absence of vertiginous experience was noticed. MRI suggested lesion in the right temporal pole. Twenty-four-hour continuous electroencephalogram (EEG) monitoring recorded periodic sharp and slow waves, originating from the right temporal lobe. The patient was completely relieved of the symptoms after surgical removal of the tumor, which was histologically confirmed as Grade I Ganglioglioma.ConclusionsAsides from the cortical pathogenesis of epileptic vertigo, this case also provides insight into the DBN secondary to tumor of the temporal lobe. Moreover, the 24-h EEG is advantageous to recognize vestibular seizures and localize the ictal onset areas.

Spontaneous downbeat nystagmus and ocular flutter are rare clinical signs. Such findings are commonly related to cerebellar pathology, predominantly ischemia. In a significant percentage of patients, the cause may not be found. If these signs are associated with ataxia, cognitive decline, and seizure, anti-glutamic acid decarboxylase-associated neurological syndrome must be suspected. Background history of tumor has to be enquired. Treatment with immune modulation helps in partial recovery of such cases.

41歳の男性で,頭位を左回旋時にC5/6椎間で左椎骨動脈が圧迫,狭窄を受け,脳虚血症状をきたした症例を経験した.既往歴としてKlippel-Feil症候群(C2/3fusion)とC6/7椎間板ヘルニアによる前方固定術があった.頸椎X線では上記所見に加え,C4/5の不安定性およびC5/6左側椎間孔に骨棘の形成があり,MRIおよびMRAでは,頭位左回旋時に左椎骨動脈が偏位して狭窄が生じ,同時に右椎骨動脈も全体的に狭小化し,flowの低下が疑われた,椎骨動脈撮影では,蛇行,狭窄に加え,両側椎骨動脈の血流の遅滞がみられた.治療は,前方アプローチでC5/6の骨棘,椎間板を除去し,腸骨を用いて前方固定術を行い,症状の消失を得た.本例の臨床症状の発生機序および治療方針について考察を加えた.

Four Cases of Vertebrobasilar Insufficiency

Aberrant right subclavian artery (ARSA) is a rare congenital malformation, wherein the aorta gives rise to the right subclavian artery as a branch off the aortic arch distal to the takeoff of the left subclavian artery. We presented a case of a patient with ARSA that manifested vertebrobasilar symptoms. PubMed search was preformed using keywords ‘aberrant right subclavian artery’, ‘right subclavian steal’ and ‘vertebrobasilar’, which generated nine articles. We found only seven case reports through a PubMed search that discuss ARSA in association with Subclavian steal syndrome. Approximately 71% (n = 5) of the patients in our literature review manifested with signs and symptoms of vertebrobasilar insufficiency. Given the complex anatomy in this condition, treatment should be aimed at symptom resolution. Carotid-subclavian bypass ultimately resolved the symptoms in our patient. Management in symptomatic patient is surgical. In addition to open technique, endovascular interventions can be an option.

We present a diagnostically challenging case of vertebrobasilar insufficiency caused by head rotation. The patient was a 58-year-old man complaining of dizziness and faintness with head rotation to the left. Vertebral arteriography with the head turned to the left revealed mechanical compression of the right vertebral artery at the occipitoatlantal joints and an occluded left vertebral artery. Duplex sonography demonstrated disappearance of the end-diastolic flow signal in the right vertebral artery on head rotation, paralleling the appearance of symptoms. Decompression of the vertebral artery by transversectomy of the atlas and hemilaminectomy of the axis completely relieved the symptoms and the Doppler flow signal pattern of the vertebral artery returned to normal: End-diastolic flow in the right vertebral artery did not disappear even when the head was rotated to the left.

Vertebrobasilar dolichoectasia (VBD) is a rare vascular condition characterized by the elongation, widening, and tortuosity of the vertebrobasilar artery. It can lead to various symptoms due to compression of cranial nerves and brainstem structures. We report a rare case of VBD presenting as sudden sensorineural hearing loss (SSNHL) with vertigo and spontaneous downbeat nystagmus in a 65-year-old woman with a history of hypertension. Magnetic resonance imaging revealed a tortuous and dilated right vertebrobasilar artery compressing the brainstem and left 8th cranial nerve root entry zone, without signs of acute cerebellar stroke. The compression of the anterior inferior cerebellar artery and cervicomedullary junction was also noted, suggesting a vascular cause for her symptoms. Following high-dose steroid treatment, the patient showed significant hearing improvement. This case underscores the importance of considering VBD in patients with unexplained SSNHL and vertigo, highlighting the role of detailed vascular imaging in the diagnosis and management of such cases.

An intronic GAA repeat expansion in the FGF14 gene was recently identified as a common cause of autosomal dominant GAA-FGF14 ataxia (SCA27B). We aimed to characterize in detail the clinical and video-oculographic features in our cohort of SCA27B patients. We genotyped the FGF14 GAA repeat expansion in 52 patients with unsolved late-onset cerebellar ataxia. Brain MRI and nerve conduction study, as well as video-oculographic (VOG) assessment, were performed. Eight patients (15.4%) with pathogenic GAA repeat expansion in the FGF14 gene were found. The median age at onset was 51 years (range—23–63 years). Sensory axonal neuropathy was found in 5/8 patients. Cerebellar atrophy was observed in 5/8 patients, and in one case, pontocerebellar atrophy was found. All tested patients had impaired smooth pursuit, 5/6 patients had impaired vestibulo-ocular reflex suppression, nystagmus, and an increased number of square wave jerks, 4/6 patients had horizontal gaze-evoked nystagmus, 3/6 had spontaneous downbeat nystagmus, and 1/6 had an upbeat one. Video head impulse test gain was lower than 0.8 on both sides in 2/4 patients, along with the presence of overt saccades. Further studies in different cohorts are needed to complete the phenotype of the FGF14-related disorders.

Reading disability due to an ocular motor disorder: A case of an adolescent girl with a previous diagnosis of dyslexia