Clinical benefit of MAO-B and COMT inhibition in Parkinson's disease: practical considerations.

Inhibitors of monoamine oxidase B (MAO-B) and catechol-O-methyltransferase (COMT) are major strategies to reduce levodopa degradation and thus to increase and prolong its effect in striatal dopaminergic neurotransmission in Parkinson's disease patients. While selegiline/rasagiline and tolcapone/entacapone have been available on the market for more than one decade, safinamide and opicapone have been approved in 2015 and 2016, respectively. Meanwhile, comprehensive data from several post-authorization studies have described the use and specific characteristics of the individual substances in clinical practice under real-life conditions. Here, we summarize current knowledge on both medication classes, with a focus on the added clinical value in Parkinson's disease. Furthermore, we outline practical considerations in the treatment of motor fluctuations and provide an outlook on ongoing studies with MAO-B and COMT inhibitors.

Risk and course of COVID-19 in immunosuppressed patients with myasthenia gravis.

BACKGROUND: Patients with myasthenia gravis (MG) are potentially prone for a severe COVID-19 course, but there are limited real-world data available on the risk associated with COVID-19 for patients with MG. Here, we investigate whether current immunosuppressive therapy (IST) influences the risk of SARS-CoV-2 infection and COVID-19 severity. METHODS: Data from the German myasthenia gravis registry were analyzed from May 2020 until June 2021 and included patient demographics, MG disease duration, comorbidities, current IST use, COVID-19 characteristics, and outcomes. Propensity score matching was employed to match MG patients with IST to those without, and multivariable binary logistic regression models were used to determine associations between IST with (1) symptomatic SARS-CoV-2 infection and (2) severe COVID-19 course, as measured by hospitalization or death. RESULTS: Of 1379 patients with MG, 95 (7%) patients (mean age 58 (standard deviation [SD] 18) presented with COVID-19, of which 76 (80%) received IST at time of infection. 32 patients (34%) were hospitalized due to COVID-19; a total of 11 patients (12%) died. IST was a risk factor for hospitalization or death in the group of COVID-19-affected MG patients (odds ratio [OR] 3.04, 95% confidence interval [CI] = 1.02-9.06, p = 0.046), but current IST was not associated with a higher risk for SARS-CoV-2 infection itself. DISCUSSION: In this national MG cohort study, current IST use was a risk factor for a severe disease course of COVID-19 but not for SARS-CoV-2 infection itself. These data support the consequent implementation of effective strategies to prevent COVID-19 in this high-risk group. TRIAL REGISTRATION INFORMATION: German clinical trial registry ( https://www.drks.de ), DRKS00024099, first patient enrolled: February 4th, 2019.

[Therapy of Hemifacial Spasm with Botulinum Toxin: an Update]. / Botulinumtoxin ­ Therapie des Spasmus hemifacialis: Ein Update.

Injections of botulinum toxin can be viewed by now as the therapy of choice in treating hemifacial spasm (HFS). Each of the three botulinum toxin-A preparations have been approved for this indication in Germany. HFS is a frequent disease characterized by involuntary contractions of the muscles of one half of the face innervated by the facial nerve. The symptoms can be either tonic or clonic, intermittant or permanent. Diagnosis is based purely on clinical observation. A magnetic resonance imagingof the skull is appropriate to demonstrate nerve-vessel contact as most frequent cause and to exclude other pathologies.

Ten Years of Improving Acute Stroke Management in a Metropolitan Area: A Population-Based Quantification of Quality Indicators.

BACKGROUND AND PURPOSE: Rapid access to acute stroke treatment improves clinical outcomes in patients with ischemic stroke. We aimed to shorten the time to admission and to acute stroke treatment for patients with acute stroke in the Hamburg metropolitan area by collaborative multilevel measures involving all hospitals with stroke units, the Emergency Medical Services (EMS), and health-care authorities. METHODS: In 2007, an area-wide stroke care quality project was initiated. The project included mandatory admission of all stroke patients in Hamburg exclusively to hospitals with stroke units, harmonized acute treatment algorithms among all hospitals, repeated training of the EMS staff, a multimedia educational campaign, and a mandatory stroke care quality monitoring system based on structured data assessment and quality indicators for procedural measures. We analyzed data of all patients with acute stroke who received inhospital treatment in the city of Hamburg during the evaluation period from the quality assurance database data and evaluated trends of key quality indicators over time. RESULTS: From 2007 to 2016, a total of 83,395 patients with acute stroke were registered. During this period, the proportion of patients admitted within ≤3 h from symptom onset increased over time from 27.8% in 2007 to 35.2% in 2016 (p < 0.001). The proportion of patients who received rapid thrombolysis (within ≤30 min after admission) increased from 7.7 to 54.1% (p < 0.001). CONCLUSIONS: Collaborative stroke care quality projects are suitable and effective to improve acute stroke care.

Discordant Monozygotic Parkinson Disease Twins: Role of Mitochondrial Integrity.

OBJECTIVE: Even though genetic predisposition has proven to be an important element in Parkinson's disease (PD) etiology, monozygotic (MZ) twins with PD displayed a concordance rate of only about 20% despite their shared identical genetic background. METHODS: We recruited 5 pairs of MZ twins discordant for idiopathic PD and established skin fibroblast cultures to investigate mitochondrial phenotypes in these cellular models against the background of a presumably identical genome. To test for genetic differences, we performed whole genome sequencing, deep mitochondrial DNA (mtDNA) sequencing, and tested for mitochondrial deletions by multiplex real-time polymerase chain reaction (PCR) in the fibroblast cultures. Further, the fibroblast cultures were tested for mitochondrial integrity by immunocytochemistry, immunoblotting, flow cytometry, and real-time PCR to quantify gene expression. RESULTS: Genome sequencing did not identify any genetic difference. We found decreased mitochondrial functionality with reduced cellular adenosine triphosphate (ATP) levels, altered mitochondrial morphology, elevated protein levels of superoxide dismutase 2 (SOD2), and increased levels of peroxisome proliferator-activated receptor-gamma coactivator-α (PPARGC1A) messenger RNA (mRNA) in skin fibroblast cultures from the affected compared to the unaffected twins. Further, there was a tendency for a higher number of somatic mtDNA variants among the affected twins. INTERPRETATION: We demonstrate disease-related differences in mitochondrial integrity in the genetically identical twins. Of note, the clinical expression matches functional alterations of the mitochondria. ANN NEUROL 2021;89:158-164.

Site and size of lesion predict post-stroke spasticity: A retrospective magnetic resonance imaging study.

OBJECTIVE: Clinical parameters for prediction of post-stroke spasticity are well established. This report introduces 2 brain magnetic resonance imaging (MRI) parameters (infarct volume and topographic distribution) as post-stroke spasticity predictors. METHODS: Topographic and volumetric data from brain MRI for 98 patients with ischaemic stroke with spasticity, prevalent within the first 5 days after stroke and 6 months after stroke, were retrospectively correlated using Chris Rorden's MRIcron software. RESULTS: Lesions within the supply territory of the middle cerebral artery involving the pyramidal tract were more frequently associated with spasticity than without spasticity (30.8% vs 5.1%). Middle cerebral artery lesions not affecting the pyramidal tract were found more often in patients without spasticity (49.2% vs 10.3%). Spasticity showed a significantly higher association with middle cerebral artery+pyramidal tract/internal capsule lesions than did "no spasticity" (97.5% vs 18.7%, p < 0.01), and lesion volumes were significantly larger in patients with spasticity than in those without spasticity (p < 0.01). CONCLUSION: Large stroke volumes might predict post-stroke spasticity if the lesion is > 3 cm3 in size and if the lesion is located within the middle cerebral artery territory with involvement of the pyramidal tract and/or internal capsule. Lesion size ≤ 2 cm3 outside the middle cerebral artery territory is associated with lower risk of post-stroke spasticity.

[Therapy of Hemifacial Spasm with Botulinum Toxin]. / Therapie des Spasmus hemifacialis mit Botulinumtoxin.

Hemifacial spasm (HFS) is a frequent disorder characterized by involuntary contractions of those muscles innervated by the facialis nerve on one side of the face. The symptoms can appear as tonic or clonic, intermittent or permanent. Diagnosis is based purely on clinical observation. Differential diagnosis should rely on cranial MRI, which can demonstrate a pathological contact between the nerves and vessels and exclude alternative causation. Often, the symptoms are not marked so that therapy may not be necessary. The therapy of choice is an injection of botulinum toxin to reduce the underlying pathological activity. As an alternative, decompression operation according to Jannetta can be considered, although it is frequently rejected by patients.

[Therapy of Hemifacial Spasm with Botulinum Toxin]. / Therapie des Spasmus hemifacialis mit Botulinumtoxin.

Hemifacial spasm (HFS) is a frequent disorder characterized by involuntary contractions of those muscles innervated by the facialis nerve on one side of the face. The symptoms can appear as tonic or clonic, intermittent or permanent. Diagnosis is based purely on clinical observation. Differential diagnosis should rely on cranial MRI, which can demonstrate a pathological contact between the nerves and vessels and exclude alternative causation. Often, the symptoms are not marked so that therapy may not be necessary. The therapy of choice is an injection of botulinum toxin to reduce the underlying pathological activity. As an alternative, decompression operation according to Jannetta can be considered, although it is frequently rejected by patients.

Trigeminal-hypoglossal silent period: a pontomedullary brainstem reflex.

INTRODUCTION: Animal studies have shown inhibitory connections between the sensory trigeminal nucleus and hypoglossal nucleus. I investigated whether these inhibitory projections are present in humans. METHODS: I examined 18 healthy subjects, 2 patients with brainstem stroke, and 5 patients with multiple sclerosis using a specially designed oral stimulation and recording device. RESULTS: In 16 of 18 subjects, a bilateral suppression period of tongue muscle activity after unilateral electrical stimulation of the mucosal V2 afferents was observed. The silent period started at 31.1 (SD 4.7) ms (ipsilateral) and 32.0 (SD 4.9) ms (contralateral). The mean duration of the silent period was 31.4 (SD 10.2) ms (ispilateral) and 32.5 (SD 9.8) ms (contralateral). Patients with dorsolateral pontomedullary lesions had ipsilateral absence of the silent period. CONCLUSIONS: This study confirms the existence of a bilateral trigeminal-hypoglossal silent period in humans.

Peripheral neuropathy in Parkinson's disease: levodopa exposure and implications for duodenal delivery.

In advanced Parkinson's disease (PD) patients, continuous intra-duodenal infusion of levodopa/carbidopa intestinal gel (LCIG) is an established approach in the management of motor complications that cannot be further improved by conventional oral therapy. In general, tolerability of LCIG has resembled that of oral dopaminergic therapy; however, cases of symptomatic peripheral neuropathy (PN), sometimes severe, have been reported in patients receiving LCIG. Cases are generally a sensorimotor polyneuropathy with both subacute and chronic onsets, often associated with vitamin B12 and/or B6 deficiency. Rare cases clinically resemble Guillain-Barré syndrome. In the absence of prospectively collected data on possible associations between LCIG and PN, it is prudent to explore potential mechanisms that may explain a possible relationship. The PN may be linked to use of high-dose levodopa, promoting high levels of homocysteine and methylmalonic acid or reduced absorption of vitamins essential for homocysteine metabolism. Cases of LCIG-associated PN often have responded to vitamin supplementation without need for LCIG cessation, although LCIG cessation is sometimes necessary. It may be advisable to monitor vitamin B12/B6 status before and after patients start LCIG and be vigilant for signs of PN. Prospective, large-scale, long-term studies are needed to clarify whether vitamin supplementation and routine use of a catechol-O-methyltransferase inhibitor may help prevent PN in LCIG recipients and whether these measures should be routine practice in patients with PD on high-dose oral levodopa.

Subacute axonal neuropathy in Parkinson's disease with cobalamin and vitamin B6 deficiency under duodopa therapy.

We describe two patients who developed subacute axonal peripheral neuropathy under duodopa treatment. Comprehensive diagnostic workup including muscle and sural nerve biopsy revealed that the most probable cause of subacute axonal peripheral neuropathy was cobalamin and vitamin B6 deficiency in both the patients.

Occurence and clinical predictors of spasticity after ischemic stroke.

BACKGROUND AND PURPOSE: There is currently no consensus on (1) the percentage of patients who develop spasticity after ischemic stroke, (2) the relation between spasticity and initial clinical findings after acute stroke, and (3) the impact of spasticity on activities of daily living and health-related quality of life. METHODS: In a prospective cohort study, 301 consecutive patients with clinical signs of central paresis due to a first-ever ischemic stroke were examined in the acute stage and 6 months later. At both times, the degree and pattern of paresis and muscle tone, the Barthel Index, and the EQ-5D score, a standardized instrument of health-related quality of life, were evaluated. Spasticity was assessed on the Modified Ashworth Scale and defined as Modified Ashworth Scale >1 in any of the examined joints. RESULTS: Two hundred eleven patients (70.1%) were reassessed after 6 months. Of these, 42.6% (n=90) had developed spasticity. A more severe degree of spasticity (Modified Ashworth Scale >or=3) was observed in 15.6% of all patients. The prevalence of spasticity did not differ between upper and lower limbs, but in the upper limb muscles, higher degrees of spasticity (Modified Ashworth Scale >or=3) were more frequently (18.9%) observed than in the lower limbs (5.5%). Regression analysis used to test the differences between upper and lower limbs showed that patients with more severe paresis in the proximal and distal limb muscles had a higher risk for developing spasticity (P

CSF phospho-tau is independent of age, cognitive status and gender of neurological patients.

CSF phospho-tau (p-tau(181)) levels have shown good diagnostic utility in differential diagnosis of Alzheimer disease (AD). Unlike total-tau (t-tau), age related changes of this promising biomarker are sparsely studied. The aim of the study was to determine whether p-tau(181) is dependent on age, cognitive status or gender in patients with different neurological diseases who underwent diagnostic lumbar puncture and who had no clinical evidence of neurodegenerative diseases. CSF levels of p-tau(181) and total-tau (t-tau) of 46 neurologic patients (age range 22-89 years; 22 male, 24 female) were analyzed. Clinical diagnoses were cerebral ischaemia (n = 6), multiple sclerosis (n = 13), epileptic seizures (n = 3), polyneuropathy (n = 9) and other neurological diagnoses (n = 15). Cognitive performance was assessed by the German version of the CERAD battery. The mean level of p-tau(181) was in accordance with previous findings in neurological patients (42.8 +/- 15.3 pg/ml) and did not differ between neurological diseases. In contrast to t-tau (r = 0.38; P = 0.009), p-tau(181) did not correlate significantly to age (r = 0.15; P = 0.308). No influence of cognitive status or gender on p-tau(181) levels could be detected. The study corroborates the independence of p-tau(181) from age, cognitive status, gender and a wide spectrum of neurological diseases. The findings suggest that neither age related neurodegenerative processes nor ischaemic or inflammatory processes are accompanied by tau protein phosphorylation. In contrast, the data support the view that p-tau(181) seems to be a sign of the highly AD-specific pattern of tau phosphorylation during formation of neurofibrillary tangles.

Congenital isolated hemifacial hyperplasia.

We report on a 14-year-old boy with congenital isolated hemifacial hyperplasia. Hemifacial hypertrophy most likely represents a minor form of congenital hemihypertrophy. MRI of the soft tissue is particularly suitable to support the diagnosis and reveal associated bony asymmetries.

Clinical and neuroradiological spectrum of isolated cortical vein thrombosis.

BACKGROUND: Isolated cortical vein thrombosis is only rarely diagnosed, although it may commonly be overlooked. RESULTS: We report on four patients with this diagnosis who all presented with focal sensorimotor seizures. The diagnosis was made by a typical CT and MRI-pattern, which is described in detail. CONCLUSIONS: The prognosis was excellent in all patients and the treatment options are discussed.

Somatotopic organization of the corticospinal tract in the human brainstem: a MRI-based mapping analysis.

To investigate the incompletely understood somatotopical organization of the corticospinal tract in the human brainstem, we performed a voxel-based statistical analysis of standardized magnetic resonance scans of 41 prospectively recruited patients with pyramidal tract dysfunction caused by acute brainstem infarction. Motor hemiparesis was rated clinically and by the investigation of motor evoked potentials to arms and legs. Infarction affected the pons in 85% of cases. We found the greatest level of significance of affected brainstem areas between the pontomesencephalic junction and the mid pons. Lesion location was significantly more dorsal in patients with hemiparesis affecting more proximal muscles and was significantly more ventral in patients with predominantly distal limb paresis. Comparison of magnetic resonance lesion from patients with paresis predominantly affecting arm or leg did not show significant topographical differences. We conclude that a topographical arm/leg distribution of corticospinal fibers is abruptly broken down as the descending corticospinal tract traverses the pons. Corticospinal fibers, however, follow a somatotopical order in the pons with fibers controlling proximal muscles being located close to the reticular formation in the dorsal pontine base, and thus more dorsal than the fibers controlling further distal muscle groups.

Seventh nerve palsies may be the only clinical sign of small pontine infarctions in diabetic and hypertensive patients.

BACKGROUND: Small brainstem infarctions are increasingly recognized as a cause of isolated ocular motor and vestibular nerve palsies in diabetic and/or hypertensive patients. This raises the question whether there are also isolated 7(th) nerve palsies due to pontine infarctions in patients with such risk factors for the development of cerebrovascular diseases. METHODS: Over an 11-year-period, we retrospectively identified 10 diabetic and/or hypertensive patients with isolated 7(th) nerve palsies and electrophysiological abnormalities indicating pontine dysfunction. All patients had examinations of masseter and blink reflexes, brainstem auditory evoked potentials, direct current electro-oculography including bithermal caloric testing, and T1- and T2-weighted MRI (slice thickness: 4-7 mm). RESULTS: Electrophysiological abnormalities on the side of the 7(th) nerve palsy included delayed masseter reflex latencies (4 patients), slowed abduction saccades (4 patients), vestibular paresis (2 patients), and abnormal following eye movements (2 patients). Electrophysiological abnormalities were always improved or normalized at re-examination, which was always associated with clinical improvement. MRI revealed an ipsilateral pontine infarction in 2 patients. Another 2 had bilateral hyperintense intrapontine lesions, and one an ipsilateral cerebellar infarction. CONCLUSIONS: Simultaneous improvement or recovery of abnormal clinical and electrophysiological findings strongly indicated that both were caused by the same actual pontine lesions. A 7(th) nerve palsy may be the only clinical sign of a pontine infarction in diabetic and/or hypertensive patients. Such mechanism may be underestimated if based on MRI only.