Stance Ataxia Research Articles

Further insights into anti-IgLON5 disease: a case with complex clinical presentation

BackgroundAnti-IgLON5 disease is an autoimmune encephalitis overlapping with neurodegenerative disorders due to pathological accumulation of hyperphosphorylated tau. It is characterized by several clinical manifestations determined by involvement of different brain areas, and mild response to first-line immunotherapies. We report a case of anti-IgLON5 disease with a multifaceted semiology and an unusually good response to glucocorticoid monotherapy.Case presentationA 68-year-old man with type 2 diabetes was evaluated for an 8-month history of progressive gait disorder causing frequent falls. He also suffered from obstructive sleep apneas and complained of dysphonia, dysarthria, occasional dysphagia, urinary incontinence, and upper limb action tremor. Neurological examination demonstrated bilateral eyelid ptosis, limitation of ocular horizontal smooth pursuit movements, slow horizontal saccades, and lack of inhibition of the vestibulo-ocular reflex during rapid horizontal head torsions. The patient also displayed involuntary, slow, rhythmic movements of the left periorbital and perioral muscles, spreading to the ipsilateral hemipalate and hemitongue, along with bilateral negative upper limb myoclonus. There were proximal muscle wasting in the upper limbs, proximal weakness of the four limbs, and diffuse fasciculations. Ataxia of stance and gait and of the four limbs was noted. MRI of the brain and spine was unremarkable; nerve conduction studies revealed a chronic, predominantly demyelinating, sensory-motor polyneuropathy, probably due to diabetes. Routine CSF examination was unrevealing and serum GFAP level was 89.6 pg/mL; however, the autoimmunity tests revealed a high-titer positivity for anti-IgLON5 autoantibodies in both CSF and serum, leading to the diagnosis of anti-IgLON5 disease. Symptoms improved significantly after intravenous methylprednisolone.ConclusionsHemifacial and hemiorolingual myorhythmia along with peculiar oculomotor abnormalities characterizes the multifaceted clinical picture of our case. The complex semiology of our patient may reflect multifocal targeting of the autoimmune process or sequential spreading of tau inclusions in different brain areas. Our patient’s optimal response to glucocorticoid monotherapy could be underpinned by a slightly different phenotype in which autoimmunity plays a greater pathogenic role than tauopathy, with a lower burden of tau deposition. In such patients, neurodegeneration and tau accumulation could be merely secondary to immune-mediated neuronal dysfunction, supporting the existence of a group of glucocorticoid-responsive patients.

Teaching Video NeuroImage: One Bedside Test, 2 Clinical Signs

A 60-year-old patient had progressive imbalance. Examination revealed saccadic smooth pursuit, downbeat nystagmus, ataxia of stance and gait, and reduced vibration sense. Video head impulse and caloric testing both showed vestibulo-ocular reflex (VOR) deficits (figure). The patient has cerebellar ataxia with neuronopathy and vestibular areflexia syndrome.1,2 Slow head turns while looking at an earth-fixed target produce saccadic rather than smooth compensatory eye movements (Videos 1) due to impairment of both the VOR and smooth pursuit (the visually enhanced VOR): 1 simple bedside test, 2 clinical signs, and 1 precise diagnosis.

Coordination and Cognition in Pure Nutritional Wernicke's Encephalopathy with Cerebellar Degeneration after COVID-19 Infection: A Unique Case Report.

Alcoholic cerebellar degeneration is a restricted form of cerebellar degeneration, clinically leading to an ataxia of stance and gait and occurring in the context of alcohol misuse in combination with malnutrition and thiamine depletion. However, a similar degeneration may also develop after non-alcoholic malnutrition, but evidence for a lasting ataxia of stance and gait and lasting abnormalities in the cerebellum is lacking in the few patients described with purely nutritional cerebellar degeneration (NCD). We present a case of a 46-year-old woman who developed NCD and Wernicke's encephalopathy (WE) due to COVID-19 and protracted vomiting, resulting in thiamine depletion. We present her clinical course over the first 6 months after the diagnosis of NCD and WE, with thorough neuropsychological and neurological examinations, standardized clinical observations, laboratory investigations, and repeated MRIs. We found a persistent ataxia of stance and gait and evidence for an irreversible restricted cerebellar degeneration. However, the initial cognitive impairments resolved. Our study shows that NCD without involvement of alcohol neurotoxicity and with a characteristic ataxia of stance and gait exists and may be irreversible. We did not find any evidence for lasting cognitive abnormalities or a cerebellar cognitive-affective syndrome (CCAS) in this patient.

Opsoclonus-myoclonus syndrome associated with pancreatic neuroendocrine tumor: a case report

BackgroundOpsoclonus-myoclonus syndrome (OMS) is a rare, immune-mediated neurological disorder. In adults, the pathogenesis can be idiopathic, post-infectious or paraneoplastic, the latter etiology belonging to the ever-expanding group of defined paraneoplastic neurological syndromes (PNS). In contrast to other phenotypes of PNS, OMS cannot be ascribed to a single pathogenic autoantibody. Here, we report the first detailed case of paraneoplastic, antibody-negative OMS occurring in association with a pancreatic neuroendocrine tumor (pNET).Case presentationA 33-year-old female presented with a two-week history of severe ataxia of stance and gait, dysarthria, head tremor, myoclonus of the extremities and opsoclonus. Her past medical history was notable for a metastatic pancreatic neuroendocrine tumor, and she was subsequently diagnosed with paraneoplastic opsoclonus-myoclonus syndrome. Further workup did not reveal a paraneoplastic autoantibody. She responded well to plasmapheresis, as she was refractory to the first-line therapy with corticosteroids.ConclusionsThis case expands current knowledge on tumors associated with paraneoplastic opsoclonus-myoclonus syndrome and the age group in which it can occur. It further adds evidence to the effectiveness of plasmapheresis in severe cases of opsoclonus-myoclonus syndrome with a lack of response to first-line therapy.

Safety and Efficacy of Acetyl-DL-Leucine in Certain Types of Cerebellar Ataxia

Cerebellar ataxia is a neurodegenerative disease impairing motor function characterized by ataxia of stance, gait, speech, and fine motor disturbances. To investigate the efficacy, safety, and tolerability of the modified essential amino acid acetyl-DL-leucine in treating patients who have cerebellar ataxia. The Acetyl-DL-leucine on Cerebellar Ataxia (ALCAT) trial was an investigator-initiated, multicenter, double-blind, randomized, placebo-controlled, clinical crossover trial. The study was conducted at 7 university hospitals in Germany and Austria between January 25, 2016, and February 17, 2017. Patients were aged at least 18 years and diagnosed with cerebellar ataxia of hereditary (suspected or genetically confirmed) or nonhereditary or unknown type presenting with a total score of at least 3 points on the Scale for the Assessment and Rating of Ataxia (SARA). Statistical analysis was performed from April 2018 to June 2018 and January 2020 to March 2020. Patients were randomly assigned (1:1) to receive acetyl-DL-leucine orally (5 g per day after 2 weeks up-titration) followed by a matched placebo, each for 6 weeks, separated by a 4-week washout, or vice versa. The randomization was done via a web-based, permuted block-wise randomization list (block size, 2) that was stratified by disease subtype (hereditary vs nonhereditary or unknown) and site. Primary efficacy outcome was the absolute change of SARA total score from (period-dependent) baseline to week 6. Among 108 patients who were randomly assigned to sequence groups (54 patients each), 55 (50.9%) were female; the mean (SD) age was 54.8 (14.4) years; and the mean (SD) SARA total score was 13.33 (5.57) points. The full analysis set included 105 patients (80 patients with hereditary, 25 with nonhereditary or unknown cerebellar ataxia). There was no evidence of a difference in the mean absolute change from baseline to week 6 in SARA total scores between both treatments (mean treatment difference: 0.23 points [95% CI, -0.40 to 0.85 points]). In this large multicenter, double-blind, randomized, placebo-controlled clinical crossover trial, acetyl-DL-leucine in the investigated dosage and treatment duration was not superior to placebo for the symptomatic treatment of certain types of ataxia. The drug was well tolerated; and ALCAT yielded valuable information about the duration of treatment periods and the role of placebo response in cerebellar ataxia. These findings suggest that further symptom-oriented trials are needed for evaluating the long-term effects of acetyl-DL-leucine for well-defined subgroups of cerebellar ataxia. EudraCT 2015-000460-34.

Vestibular Dysfunction in Wernicke's Encephalopathy: Predominant Impairment of the Horizontal Semicircular Canals.

Wernicke's encephalopathy (WE), a metabolic disorder due to thiamine deficiency, manifests with various neurological symptoms and signs. It has been known as a cause of vestibular dysfunction. Preliminary reports have proposed predominant involvement of the horizontal semicircular canals (HSCs). To better characterize the pattern of vestibular impairment in patients with WE using quantitative video head-impulse testing and to review the literature regarding this topic. From January 2014 to December 2016, we retrospectively enrolled five cases of WE that received quantitative video-head-impulse testing (vHIT). We retrieved the clinical features from the medical records and reviewed quantitative head-impulse testing (qHIT) and caloric irrigation. Based on the gain and the number of corrective saccades, the function (normal vs. impaired) of each semicircular canal was rated. In addition, we conducted a MEDLINE and EMBASE search to identify other published cases of WE that had received qHIT. Neuro-otologic and neuro-ophthalmologic findings and vestibular testing results were extracted. A total of 17 patients (own series = 5; published cases = 12) aged 54.6 ± 11 years were included. Key neurologic findings were ataxia of stance and gait (13/13, 100%), spontaneous nystagmus (7/14, 50%), gaze-evoked nystagmus (GEN) (17/17, 100%), positive bedside head-impulse testing for the horizontal canals (16/17, 94%), and memory impairment and mental changes (6/11, 54.5%). Regarding vestibular testing, qHIT (either video based or search-coil based) documented selective bilateral horizontal canal dysfunction with normal or minimal vertical canal impairment (14/14, 100%). On caloric irrigation, bilateral horizontal canal paresis was noted in most cases (10/11, 91%). In WE, signs of both peripheral and central vestibular dysfunction (i.e., GEN, ataxia of stance and gait, abnormal head-impulse testing) were common. Selective or predominant impairment of the HSCs seems to be the most common finding of WE likely related to enhanced vulnerability of the medial vestibular nuclei neurons to thiamine deficiency. Quantitative vHIT of all six semicircular canals is therefore a useful tool for the diagnosis and should be applied in all patients with suspected WE.

Functional recovery and rehabilitation of postural impairment and gait ataxia in patients with acute cerebellar stroke

Studies about recovery from cerebellar stroke are rare. The present study assessed motor deficits in the acute phase after isolated cerebellar stroke focusing on postural impairment and gait ataxia and outlines the role of lesion site on motor outcome, the course of recovery and the effect of treadmill training. 23 patients with acute and isolated cerebellar infarction participated. Deficits were quantified by ataxia scores and dynamic posturography in the acute phase and in a follow up after 2 weeks and 3 months. MRI data were obtained to correlate lesion site with motor performance. Half of the patients that gave informed consent and walked independently underwent a 2-week treadmill training with increasing velocity. In the acute phase patients showed a mild to severe ataxia with a worse performance in patients with infarction of the superior in comparison to the posterior inferior cerebellar artery. However, after 3 months differences between vascular territories were no longer significant. MRI data showed that patients with larger infarct volumes had a significantly more severe ataxia. In patients with ataxia of stance, gait and lower limbs lesions were more common in cerebellar lobules IV to VI. After 3 months a mild ataxia in lower limbs and gait, especially in gait speed persisted. Because postural impairment had fully recovered, remaining gait ataxia was likely related to incoordination of lower limbs. Treadmill training did not show significant effects. Future studies are needed to investigate whether intensive coordinative training is of benefit in patients with cerebellar stroke.

Exome sequencing in roma families identifies tandem GRM1 mutations in a novel form of congenital cerebellar ataxia

Recessive ataxias are heterogeneous group of rare monogenic disorders with genetic pathology largely unresolved. Aim To identify the molecular defect underlying a novel congenital ataxia phenotype in a small Roma sub-isolate with a known strong founder effect. Methods The patients were assessed by an international multidis-ciplinary team. Whole exome sequencing data were used for inbreeding and relatedness estimates, linkage analysis and mutation detection. Functional mutation impact in patient lymphoblastoid cell lines was studied by reverse transcription/real-time PCR. Results The major clinical manifestations included global developmental delay, gait and stance ataxia, intellectual deficit, and progressive cerebellar atrophy. Novel tandem deletion c.2652_2654del:p.884_885del and a splicing mutation c.2660+2T>G, 7 bp apart in the metabotropic glutamate receptor gene GRM1, were the only homozygous variants in all affected subjects both exome-wide and within a unique linkage region. The splicing defect had a major functional impact, with exon skipping or transcript termination in the neighboring intron producing various species of nonfunctional receptors either lacking the trans-membrane domain and containing abnormal intracellular tails or completely missing the tail. Discussion The study is the first to implicate GRM1 in hereditary ataxia and to highlight the potential of exome sequencing in the Roma population for disease gene and mutation identification

Clinical, electrophysiological, and MRI findings in patients with cerebellar ataxia and a bilaterally pathological head‐impulse test

A significant number of patients with bilateral vestibulopathy suffer from cerebellar ataxia and central vestibular symptoms and vice versa. We examined 31 patients presenting with the combination of gait and stance ataxia, cerebellar ocular motor signs, and a bilaterally pathological head-impulse test (HIT). Tests included neuro-orthoptical examination, electromyography and neurography, caloric irrigation, pure-tone audiogram, vestibular-evoked myogenic potentials, and volumetric magnetic resonance imaging (MRI). Only 17 of 31 patients had a pathological caloric irrigation. Twenty-three patients had evidence of polyneuropathy (predominantly mixed sensorimotor involving axonal loss and demyelination) and twenty of hypoacusis (1 unilateral and 19 bilateral). Voxel-based morphometry comparing local gray matter brain volume between patients and controls revealed cerebellar atrophy involving both the vermis and the hemispheres. We conclude that there is a clinically relevant combination of cerebellar ataxia with cerebellar atrophy, bilaterally pathological HIT, polyneuropathy, and hypoacusis. This multisensory syndrome is most likely caused by a neurodegenerative disorder affecting different systems, leading to severe impairment of affected patients.

A new case of chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids

Sir, We read with great interest the recent article published in Brain by Pittock and colleagues (2010) describing eight patients with a previously unrecognized distinct brainstem encephalitis named chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS). Here, we report on what we believe to be another patient with CLIPPERS, lending further support to the concept that CLIPPERS is a novel, definable, inflammatory CNS disease. The patient provided written informed consent for presentation of her case as a report. A 69-year-old female noticed general weakness, dizziness and abnormal fatigue with subacute onset 16 weeks prior to evaluation at the Department of Neurology, Charite, Universitatsmedizin, Berlin. Eleven weeks prior, the patient developed horizontal diplopia and walking difficulties that gradually worsened so that she became unable to walk without assistance. Additionally, she noticed dysarthria and dysphagia as well as facial tingling and paraesthesia in her fingertips. About 4 weeks prior to admission, she developed hyperacusis and a labile affect with involuntary crying. Her past medical history was unremarkable except for arterial hypertension, which was treated with bisoprolol. Her family history was negative. Neurological examination on admission revealed a cerebellar syndrome with limb, gait and stance ataxia, as well as intention tremor on the left, more than on the right-hand side. She had marked cerebellar dysarthria. Her gait …

Topography of Cerebellar Deficits in Humans

The cerebellum is a key-piece for information processing and is involved in numerous motor and nonmotor activities, thanks to the anatomical characteristics of the circuitry, the enormous computational capabilities and the high connectivity to other brain areas. Despite its uniform cytoarchitecture, cerebellar circuitry is segregated into functional zones. This functional parcellation is driven by the connectivity and the anatomo-functional heterogeneity of the numerous extra-cerebellar structures linked to the cerebellum, principally brain cortices, precerebellar nuclei and spinal cord. Major insights into cerebellar functions have been gained with a detailed analysis of the cerebellar outputs, with the evidence that fundamental aspects of cerebrocerebellar operations are the closed-loop circuit and the predictions of future states. Cerebellar diseases result in disturbances of accuracy of movements and lack of coordination. The cerebellar syndrome includes combinations of oculomotor disturbances, dysarthria and other speech deficits, ataxia of limbs, ataxia of stance and gait, as well as often more subtle cognitive/behavioral impairments. Our understanding of the corresponding anatomo-functional maps for the human cerebellum is continuously improving. We summarize the topography of the clinical deficits observed in cerebellar patients and the growing evidence of a regional subdivision into motor, sensory, sensorimotor, cognitive and affective domains. The recently described topographic dichotomy motor versus nonmotor cerebellum based upon anatomical, functional and neuropsychological studies is also discussed.

Recovery of stance and gait ataxia in children with acute surgical lesions

Introduction: A previous study of our group in adolescents and young adults with chronic surgical cerebellar lesions has shown that recovery depends on lesion site. If lesions affected the cerebellar nuclei recovery was worse compared to lesions affecting the cerebellar cortex alone. In a prospective study in children we were interested if motor impairment is already different in acute surgical lesions affecting the cerebellar nuclei or not. Severity of ataxia of stance and gait were assessed 3 and 12 months following surgery.

Lesion-Symptom Mapping of the Human Cerebellum

High-resolution structural magnetic resonance imaging (MRI) has become a powerful tool in human cerebellar lesion studies. Structural MRI is helpful to analyse the localisation and extent of cerebellar lesions and to determine possible extracerebellar involvement. Functionally meaningful correlations between a cerebellar lesion site and behavioural data can be obtained both in subjects with degenerative as well as focal cerebellar disorders. In this review, examples are presented which demonstrate that MRI-based lesion-symptom mapping is helpful to study the function of cerebellar cortex and cerebellar nuclei. Behavioural measures were used which represent two main areas of cerebellar function, that is, motor coordination and motor learning. One example are correlations with clinical data which are in good accordance with the known functional compartmentalisation of the cerebellum in three sagittal zones: In patients with cerebellar cortical degeneration ataxia of stance and gait was correlated with atrophy of the medial (and intermediate) cerebellum, oculomotor disorders with the medial, dysarthria with the intermediate and limb ataxia with atrophy of the intermediate and lateral cerebellum. Similar findings were obtained in patients with focal lesions. In addition, in patients with acute focal lesions, a somatotopy in the superior cerebellar cortex was found which is in close relationship to animal data and functional MRI data in healthy control subjects. Finally, comparison of data in patients with acute and chronic focal lesions revealed that lesion site appears to be critical for motor recovery. Recovery after lesions to the nuclei of the cerebellum was less complete. Another example which extended knowledge about functional localisation within the cerebellum is classical conditioning of the eyeblink response, a simple form of motor learning. In healthy subjects, learning rate was related to the volume of the cortex of the posterior cerebellar lobe. In patients with focal cerebellar lesions, acquisition of eyeblink conditioning was significantly reduced in lesions including the cortex of the superior posterior lobe, but not the inferior posterior lobe. Disordered timing of conditioned eyeblink responses correlated with lesions of the anterior lobe. Findings are in good agreement with the animal literature. Different parts of the cerebellar cortex may be involved in acquisition and timing of conditioned eyeblink responses in humans. These examples demonstrate that MRI-based lesion-symptom mapping is helpful to study the contribution of functionally relevant cerebellar compartments in motor control and recovery in patients with cerebellar disease. In addition, information about the function of cerebellar cortex and nuclei can be gained.

Potassium channel blocker 4‐aminopyridine is effective in interictal cerebellar symptoms in episodic ataxia type 2 — A video case report

Episodic ataxia type 2 (EA2) is an autosomal-dominant hereditary disorder clinically characterized by recurrent attacks of vertigo, imbalance and ataxia. Studies have shown that 4-aminopyridine (4-AP) is capable to prevent these attacks. However, there are no reports whether 4-AP is able to attenuate interictal cerebellar ataxia. Using the scale for assessment and rating of ataxia (SARA), we examined the efficacy of 4-AP on interictal ataxia in a 63-year-old female patient who suffered from EA2 since the age of 57. EA2 was diagnosed based on clinical criteria and not genetically proven. When treatment with 4-AP was paused the patient was suffering from marked gait and stance ataxia. After re-initiation of treatment with 5 mg 4-AP t.i.d., there was pronounced improvement in gait and stance ataxia. Within 24 hours SARA score lowered from 8.5 to 4.5 points. We conclude that 4-AP may be beneficial for interictal cerebellar ataxia in late onset EA2.

Stance ataxia and delayed leg muscle responses to postural perturbations in cervical spondylotic myelopathy

We studied balance control in patients with cervical spondylosis, on the hypothesis that ataxia and changes in postural responses occur concurrently as a consequence of structural problems in the cervical cord. Seventeen patients and 17 healthy subjects were recruited. Based on magnetic resonance imaging, the patients were divided into 2 groups, with (n=9) and without (n=8) signs of myelopathy. Body sway was recorded under quiet stance on a force platform. Postural perturbations evoked early and late responses in soleus and tibialis anterior. Most patients showed increased body sway during stance, which was larger in cervical spondylosis with myelopathy than cervical spondylosis. Early postural responses in the soleus were not affected. Late responses in soleus and tibialis anterior were delayed in cervical spondylosis with myelopathy. Across all patients, latency of tibialis anterior late response was correlated with lower limb sensory impairment and amplitude of body sway. Abnormal transmission through the cervical cord of proprioceptive input to supraspinal centres and of descending commands to caudal cord levels are accountable for ataxia in cervical spondylosis with myelopathy. Stabilometry may be an economic and easy way in a clinical and rehabilitative setting to distinguish severe from mild forms of cervical spondylosis prior to physical treatment and to help the differential diagnosis from other diseases featuring similar signs.

Impaired vestibular–proprioceptive interaction in cerebellar patients

Background: Vestibulo-spinal reflexes depend on adequate interaction between vestibular and proproceptive signals. Animal experiments indicate that the cerebellum is involved in this fundamental task. Cerebellar disease often leads to deficits in motor control, e.g. stance and gait ataxia. This study examines if vestibular-proprioceptive interaction might be one clinically relevant component of motor disturbance in cerebellar disease. Methods: Patients with cerebellar disorders of different etiology and normal controls were subjected to sinusoidal galvanic vestibular stimulation (0.16Hz) while standing on a force platform that measured reflectory body sway. Head-on-trunk position in the horizontal plane was altered systematically between +-60 degrees, controlled by a mechanical restraining device. Results: Normal controls exhibited a systematic dependence of their dominant sway direction on head-on-trunk position, as previously shown, keeping sway direction approximately aligned with their interaural line. In contrast, this systematic dependence was absent or attenuated in many cerebellar patients. Conclusion: In accord with results from animal experiments, the present data indicate that processing of vestibular and proprioceptive signals can be impaired in cerebellar patients. This impairment of vestibularproprioceptive interaction may be an important aspect of deficient motor control, particularly of gait and stance ataxia, in cerebellar disease.

Impaired vestibular-proprioceptive interaction in cerebellar patients

Background: Vestibulo-spinal reflexes depend on adequate interaction between vestibular and proproceptive signals. Animal experiments indicate that the cerebellum is involved in this fundamental task. Cerebellar disease often leads to deficits in motor control, e.g. stance and gait ataxia. This study examines if vestibular-proprioceptive interaction might be one clinically relevant component of motor disturbance in cerebellar disease. Methods: Patients with cerebellar disorders of different etiology and normal controls were subjected to sinusoidal galvanic vestibular stimulation (0.16Hz) while standing on a force platform that measured reflectory body sway. Head-on-trunk position in the horizontal plane was altered systematically between +-60 degrees, controlled by a mechanical restraining device. Results: Normal controls exhibited a systematic dependence of their dominant sway direction on head-on-trunk position, as previously shown, keeping sway direction approximately aligned with their interaural line. In contrast, this systematic dependence was absent or attenuated in many cerebellar patients. Conclusion: In accord with results from animal experiments, the present data indicate that processing of vestibular and proprioceptive signals can be impaired in cerebellar patients. This impairment of vestibularproprioceptive interaction may be an important aspect of deficient motor control, particularly of gait and stance ataxia, in cerebellar disease.

Persistence of disturbed thalamic glucose metabolism in a case of Wernicke–Korsakoff syndrome

We report the case of a 40-year-old alcoholic male patient, hospitalized with an acute ataxia of stance and gait, ocular muscle weakness with nystagmus and a global apathetic-confusional state. After admission, an amnestic syndrome with confabulation was also observed and diagnosis of Wernicke–Korsakoff syndrome was made. Under treatment with intravenous thiamine, the patient recovered completely from gaze weakness and ataxia, whereas a severe amnestic syndrome persisted. Fluorodeoxyglucose (FDG) positron emission tomography (PET) showed bilateral thalamic and severe bilateral temporal–parietal hypometabolism resembling a pattern typical for Alzheimer's disease. Longitudinal assessment of the alcohol-abstinent and thiamine-substituted patient revealed improvements of clinical state and neuropsychological performance that were paralleled by recovered cerebral glucose metabolism. In contrast to metabolic rates that increased between 7.1% (anterior cingulate, left) and 23.5% (parietal, left) in cortical areas during a 9-month remission period, thalamic glucose metabolism remained severely disturbed over time (change: left +0.2%, right +0.3%).

Cerebellar Agenesis: Clinical, Neuropsychological and MR Findings

Cases of cerebellar agenesis are rare. The degree of motor impairment is a matter of discussion. It has been claimed that normal motor function can be observed. Detailed descriptions of neurological findings, however, are lacking. Neuropsychological testing in cerebellar agenesis is of additional interest based on recent findings of impaired non-motor functions in cerebellar disease. The case of an elderly woman with cerebellar agenesis is presented. 3D-MR imaging was used to confirm the diagnosis. Neurological and neuropsychological examination was performed including video documentation (see the authors’ own website). To assess deficits of motor learning eyeblink conditioning was investigated. Neurological examination revealed mild to moderate signs of cerebellar dysarthria, upper and lower limb ataxia and ataxia of stance and gait. Motor learning was affected as shown by inability to acquire conditioned eyeblink responses. In addition, neuropsychological testing disclosed mild to moderate deficits in IQ, planning behavior, visuospatial abilities, memory and attention. Cerebellar ataxia, although clearly present, was less than one would expect in almost complete absence of the cerebellum. Neuropsychological deficits, on the other hand, appeared to be more marked than one would expect in cerebellar disease. No conclusion, however, could be drawn whether impaired cognitive development and neuropsychological test performance were directly related to lack of cerebellar function, or caused by impaired motor development and performance.

Wernicke's encephalopathy

A 36-year-old man was admitted to the emergency ward in a global confusional state. Apart from the patient's name and age no further information on the history was obtainable. Neurological examination revealed intermittent upbeat nystagmus, convergent strabismus, horizontal gaze palsy, and a severe ataxia of stance and gait. Laboratory findings showed an elevation of gamma-glutamyl transpeptidase, serum amylase and serum lipase, and a macrocytic anaemia. Drug and alcohol testing was negative. Based on the classical triad of clinical features—ophthalmoplegia, ataxia, and confusion—Wernicke's encephalopathy was diagnosed and thiamine was administered immediately.