Wallerian degeneration of the bilateral middle cerebellar peduncles secondary to pontine infarction

Neurological Sciences -     

A case showing Wallerian degeneration of the bilateral middle cerebellar peduncles on MRI followed by the right pontine infarction]

We report a 63-year-old man who presented with the left facial palsy, the left hemiparesis, the left limb ataxia, and the bilateral truncal ataxia. On admission, magnetic resonance imaging (MRI) showed an abnormal high intensity lesion at the right paramedian region of the upper to middle pons on T2-weighted images (T2WI). He was diagnosed as having a pontine lacunar infarction. The contralateral cerebellar lesions were caused by involvement of the pontocerebellar fibers. On the 29th day from the onset, MRI showed the new abnormal high intensity lesions at the bilateral middle cerebellar peduncles on T2WI. These lesions were supposed to be Wallerian degeneration caused by involvement of the pontocerebellar fibers. This case suggests that Wallerian degeneration occurs followed by a unilateral infarction involving pontocerebellar fibers.     

急性桥臂梗死的临床特点

目的 研究急性桥臂梗死的临床特点.方法 对27例急性桥臂梗死患者的临床资料进行回顾性分析.结果 本组患者表现为头晕20例,其中伴行走不稳9例;恶心、呕吐10例,耳鸣4例,听力减退5例,水平性眼震5例,一侧眼球外展受限2例,中枢性面瘫2例,周围性面瘫3例,一侧肢体中枢性瘫痪5例,四肢瘫痪1例,一侧面部痛觉减退4例,共济失调9例.头颅CT检查示桥臂梗死10例(37％).头颅MRI检查23例患者,均示桥臂长T1、长T2、DWI高信号的新梗死灶(100％),其中21例为单侧、2例为双侧桥臂梗死.结论 急性桥臂梗死以前庭神经和小脑损害的表现为主,以及存在三叉神经、面神经、展神经和锥体束受累的表现.MRI对其诊断的准确性很高,应作为诊断的首选检查方法.     

Transient upbeat nystagmus due to unilateral focal pontine infarction

Upbeat nystagmus is known to be caused by an imbalance of the vertical vestibulo-ocular reflex (VOR), favoring downward VOR activity, due to bilateral lesions of the medulla, ventral tegmentum, anterior cerebellar vermis, adjacent brachium conjunctivum and the midbrain. We report on two patients who had transient upbeat nystagmus due to unilateral pontine infarction that may have disrupted bilateral upward VOR pathways running in the ventral tegmental tracts.     

Subtle disruption of the middle cerebellar peduncles in patients with schizophrenia

Diffusion tensor imaging (DTI) was used to investigate subtle disruption in the middle cerebellar peduncles in patients with schizophrenia. Fractional anisotropy (FA) was measured in 25 patients with schizophrenia and 21 healthy subjects using DTI. The FA of the right and left middle cerebellar peduncles was significantly lower in the schizophrenic patients compared to healthy subjects. FA in the left middle cerebellar peduncles was significantly correlated with the dosage of neuroleptics in patients with schizophrenia. There were no significant differences of mean diffusivity in the right and left middle cerebellar peduncles between patients with schizophrenia and healthy subjects. The findings of the study suggest that antipsychotics may improve the subtle disruption in the middle cerebellar peduncles in patients with schizophrenia.     

Bilateral total deafness due to pontine haematoma.

A 64 year old woman with a predominantly midline pontine tegmental haemorrhage presented with bilateral total deafness. One week later reasonable pure-tone thresholds appeared but she still had total bilateral loss of speech discrimination. At that time contralateral acoustic reflexes were bilaterally absent, whereas ipsilateral acoustic reflexes and waves IV and V of the brainstem auditory evoked potential were bilaterally preserved. It is proposed that this patient's hearing deficit was due to inactivation of the ventral acoustic striae decussating in the trapezoid body. This case supports the contention that in humans the ventral pontine acoustic decussation carries most of the neural signals required for hearing and perhaps all the neural signals required for speech perception.     

Pure dysarthria due to pontine infarction]

A 60-year-old man developed dysarthria in the morning. Neurological examination revealed no abnormality except for dysarthria. We diagnosed the patient as having a lacunar infarction. T2-weighted brain MRI revealed hyperintense lesion in the ventrolateral portion of the left upper pontine base. The clinical symptom completely disappeared on day 20. This is the first report on the MRI findings of the patient who showed pure dysarthria, which responsible lesion is in the pontine base. Involvement of corticopontine and corticobulbar tracts were considered to be responsible for the dysarthria in this case. This case may be useful for the somatotopy of corticopontine and corticobulbar tracts with articulation in the pontine base.     

急性双侧小脑中脚缺血性卒中一例

<正>患者女性,87岁。因头晕伴站立不稳3 d,于2014年3月31日入院。患者入院前3 d突发头晕伴站立不稳、行走不能,无头痛或视物旋转。外院急诊头部CT检查显示双侧基底节区、放射冠多发性腔隙,呈增龄性改变,临床诊断为腔隙性梗死。予以醒脑静注射液20 ml/d和丹红注射液20 ml/d静脉滴注,连续治疗3 d后病情无明显改善,遂以"头晕、行走不稳待查"收入我院神经内科。患者既往有明确     

Bilateral in utero cerebellar infarction

We report a case of complete bilateral cerebellar infarction diagnosed in utero by routine prenatal ultrasound and magnetic resonance imaging in a 26-week-old fetus. This posterior fossa ischemic stroke with secondary hemorrhage caused transient obstructive hydrocephalus and likely occurred subsequent to vertebrobasilar artery thrombosis. Such posterior fossa ischemic insults diagnosed in utero are rare with scarce clinical reports. The serial imaging characteristics, clinical, and developmental implications of this case are reviewed.     

Diffusion tensor imaging study of the middle cerebellar peduncles in patients with schizophrenia

Recent evidence from neuroimaging studies suggests that neural dysfunction is involved in the pathophysiology of schizophrenia. Diffusion tensor imaging (DTI) is a technique that has the potential to detect subtle disruptions of neural connectivity. Fractional anisotropy (FA), which is measured by DTI, is a measure of the directionality of diffusion anisotropy. Decrease in FA indicates abnormalities of white matter due to increased water diffusion accompanied by an increase in extracellular space. In the literature, previous studies reported that patients with schizophrenia showed widespread lower FA in the white matter. These findings suggest that patients with schizophrenia have microstructural lesions in the cerebral white matter. We used DTI to determine whether neural connectivity was disturbed in the middle cerebellar peduncles in schizophrenic subjects. We found a significant FA reduction in the middle cerebellar peduncle in patients with schizophrenia. Therefore, neural disconnectivity between the cerebellum and cerebrum was considered present in patients with schizophrenia and may be involved in the pathology of schizophrenia. This review provides current findings regarding DTI study on the cerebellar peduncle in patients with schizophrenia.