Ultrasonography of the Adrenal Gland

With appropriate techniques and using liver, spleen or kidney as an acoustic window, normal adrenal gland and adrenal lesions can be delineated by ultrasonography. The right adrenal gland is usually evaluated by transverse oblique scans and coronal scans, respectively, through the anterior and middle axillary line, while the left adrenal gland is investigated by an oblique coronal scan mainly through the posterior axillary line. For adrenal lesions, ultrasonography has a sensitivity of 74–97%, a specificity of 61–96%, and an accuracy of 70–97%. The diagnostic accuracy depends on the scanning technique and expertise of the operator, the body status of the patient, the size and functional status of the lesion, and the ultrasonographic quality. Small adrenal nodules, ileus, obesity, fatty liver, and large body status account for most of the reasons for decreased accuracy. Small adrenal nodules less than 3 cm in diameter mainly comprise functioning cortical adenomas, nonfunctioning cortical adenomas, nodular hyperplasia, and metastases. Most small adrenal masses are homogeneous and hypoechoic, and the echo patterns are nonspecific. Large adrenal masses greater than 3 cm in diameter mainly include primary adrenocortical carcinoma, lymphoma, metastasis, lymphoma, and pheochromocytoma. The echogenicity of a large adrenal mass may be hyperechoic and heterogeneous because of the higher incidence of necrosis and hemorrhage. Other uncommon adrenal masses are myelolipoma, hematoma, granulomatous lesions, hemangioma, and adrenal cysts of various origins. The differential diagnoses of a hyperechoic adrenal mass include neuroblastoma, myelolipoma, and tumor with central necrosis or heterogeneity. Calcification is encountered in both benign and malignant processes. It is sometimes difficult to differentiate benign adrenal masses from malignant lesions. Dynamic computed tomography, magnetic resonance imaging, and positron emission tomography play critical complementary roles in such an instance

The interrelation between clinical presentation and neurophysiology of posthypoxic myoclonus

ObjectivePosthypoxic myoclonus (PHM) in the first few days after resuscitation can be divided clinically into generalized and focal (uni- and multifocal) subtypes. The former is associated with a subcortical origin and poor prognosis in patients with postanoxic encephalopathy (PAE), and the latter with a cortical origin and better prognosis. However, use of PHM as prognosticator in PAE is hampered by the modest objectivity in its clinical assessment. Therefore, we aimed to obtain the anatomical origin of PHM with use of neurophysiological investigations, and relate these to its clinical presentation. MethodsThis study included 20 patients (56 18 y/o, 68% M, 2 survived, 1 excluded) with EEG-EMG-video recording. Three neurologists classified PHM into generalized or focal PHM. Anatomical origin (cortical/subcortical) was assessed with basic and advanced neurophysiology (Jerk-Locked Back Averaging, coherence analysis). ResultsClinically assessed origin of PHM did not match the result obtained with neurophysiology: cortical PHM was more likely present in generalized than in focal PHM. In addition, some cases demonstrated co-occurrence of cortical and subcortical myoclonus. Patients that recovered from PAE had cortical myoclonus (1 generalized, 1 focal). InterpretationHypoxic damage to variable cortical and subcortical areas in the brain may lead to mixed and varying clinical manifestations of myoclonus that differ of those patients with myoclonus generally encountered in the outpatient clinic. The current clinical classification of PHM is not adequately refined to play a pivotal role in guiding treatment decisions to withdraw care. Our neurophysiological characterization of PHM provides specific parameters to be used in designing future comprehensive studies addressing the potential role of PHM as prognosticator in PAE

Neurofilament light chain, a biomarker for polyneuropathy in systemic amyloidosis

OBJECTIVE: To study serum neurofilament light chain (sNfL) in amyloid light chain (AL) amyloidosis patients with and without polyneuropathy (PNP) and to corroborate previous observations that sNfL is increased in hereditary transthyretin-related (ATTRv) amyloidosis patients with PNP. METHODS: sNfL levels were assessed retrospectively in patients with AL amyloidosis with and without PNP (AL/PNP+ and AL/PNP-, respectively), patients with ATTRv amyloidosis and PNP (ATTRv/PNP+), asymptomatic transthyretin (TTR) gene mutation carriers (TTRv carriers) and healthy controls. Healthy controls (HC) were age- and sex-matched to both AL/PNP- (HC/AL) and TTRv carriers (HC/TTRv). The single-molecule array (Simoa) assay was used to assess sNfL levels. RESULTS: sNfL levels were increased both in 10 AL/PNP+ patients (p  I) had the highest sNfL levels compared to patients with early PNP (PND-score I) (p = .05). sNfL levels did not differ between TTRv carriers and HC/TTRv individuals. In the group comprising all healthy controls and in the group of TTRv carriers, sNfL levels correlated with age. CONCLUSION: sNfL levels are increased in patients with PNP in both AL and ATTRv amyloidosis and are related to severity of PNP in ATTRv amyloidosis. sNfL is a promising biomarker to detect PNP, not only in ATTRv but also in AL amyloidosis

Eye movement disorders and neurological symptoms in late-onset inborn errors of metabolism

Inborn errors of metabolism in adults are still largely unexplored. Despite the fact that adult-onset phenotypes have been known for many years, little attention is given to these disorders in neurological practice. The adult-onset presentation differs from childhood-onset phenotypes, often leading to considerable diagnostic delay. The identification of these patients at the earliest stage of disease is important, given that early treatment may prevent or lessen further brain damage. Neurological and psychiatric symptoms occur more frequently in adult forms. Abnormalities of eye movements are also common and can be the presenting sign. Eye movement disorders can be classified as central or peripheral. Central forms are frequently observed in lysosomal storage disorders, whereas peripheral forms are a key feature of mitochondrial disease. Furthermore, oculogyric crisis is an important feature in disorders affecting dopamine syntheses or transport. Ocular motor disorders are often not reported by the patient, and abnormalities can be easily overlooked in a general examination. In adults with unexplained psychiatric and neurological symptoms, a special focus on examination of eye movements can serve as a relatively simple clinical tool to detect a metabolic disorder. Eye movements can be easily quantified and analyzed with video-oculography, making them a valuable biomarker for following the natural course of disease or the response to therapies. Here, we review, for the first time, eye movement disorders that can occur in inborn errors of metabolism, with a focus on late-onset forms. We provide a step-by-step overview that will help clinicians to examine and interpret eye movement disorders. (c) 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society

Longitudinal analysis of serum neurofilament light chain levels as marker for neuronal damage in hereditary transthyretin amyloidosis

Objective: To evaluate serum neurofilament light chain (sNfL) as biomarker of disease onset, progression and treatment effect in hereditary transthyretin (ATTRv) amyloidosis patients and TTR variant (TTRv) carriers. Methods: sNfL levels were assessed longitudinally in persistently asymptomatic TTRv carriers (N = 12), persistently asymptomatic ATTRv amyloidosis patients (defined as asymptomatic patients but with amyloid detectable in subcutaneous abdominal fat tissue) (N = 8), in TTRv carriers who developed polyneuropathy (N = 7) and in ATTRv amyloidosis patients with polyneuropathy on treatment (TTR-stabiliser (N = 20) or TTR-silencer (N = 18)). Polyneuropathy was confirmed by nerve conduction studies or quantitative sensory testing. sNfL was analysed using a single-molecule array assay. Results: sNfL increased over 2 years in persistently asymptomatic ATTRv amyloidosis patients, but did not change in persistently asymptomatic TTRv carriers. In all TTRv carriers who developed polyneuropathy, sNfL increased from 8.4 to 49.8 pg/mL before the onset of symptoms and before polyneuropathy could be confirmed neurophysiologically. In symptomatic ATTRv amyloidosis patients on a TTR-stabiliser, sNfL remained stable over 2 years. In patients on a TTR-silencer, sNfL decreased after 1 year of treatment. Conclusion: sNfL is a biomarker of early neuronal damage in ATTRv amyloidosis already before the onset of polyneuropathy. Current data support the use of sNfL in screening asymptomatic TTRv carriers and in monitoring of disease progression and treatment effect

Age-related botulinum toxin effects on muscle fiber conduction velocity in non-injected muscles

Objective: We studied systemic effects of botulinum toxin (BTX) treatment on muscle fiber conduction velocity (MFCV) and possible effects of age. Methods: MFCV was determined by an invasive EMG method in the biceps brachii muscle. Seventeen BTX treated patients and 58 controls were investigated. BTX injections were applied in the neck region or forearm, depending on the indication for treatment. Results: We found an increased ratio between fastest and slowest muscle fiber conduction velocity in BTX treated patients. This suggests systemic BTX effects on MFCV distant from the site of injection, probably fiber atrophy secondary to end-plate dysfunction. Furthermore, we found an increased MFCV in part of the patients, suggesting hypertrophy of some of the muscle fibers. No relation was found between the MFCV disturbances and treatment duration or the cumulative dose of BTX. Conclusions: We found a strong positive correlation between the age and the BTX-induced changes of MFCV in patients, suggesting a BTX related, diminished repair capacity of end-plates or muscle fibers with age. Significance: Our findings suggest a reduced repair capacity of end-plates or muscle fibers in elderly patients. MFCV is a sensitive method to show changes related to damage and compensation of the neuromuscular system. Our finding suggests a decreasing efficiency of repair mechanisms in aging. (c) 2007 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved

A new surface electromyography analysis method to determine spread of muscle fiber conduction velocities

Muscle fiber conduction velocity (MFCV) estimation from surface signals is widely used to study muscle function, e. g., in neuromuscular disease and in fatigue studies. However, most analysis methods do not yield information about the velocity distribution of the various motor unit action potentials. We have developed a new method-the interpeak latency method (IPL)-to calculate both the mean MFCV and the spread of conduction velocities in vivo, from bipolar surface electromyogram (sEMG) during isometric contractions. sEMG was analyzed in the biceps brachii muscle in 15 young male volunteers. The motor unit action potential peaks are automatically detected with a computer program. Associated peaks are used to calculate a mean MFCV and the SD. The SD is taken as a measure of the MFCV spread. The main finding is that the IPL method can derive a measure of MFCV spread at different contraction levels. In conclusion, the IPL method provides accurate values for the MFCV and additionally gives information about the scatter of conduction velocities

A new surface electromyography analysis method to determine spread of muscle fiber conduction velocities

Contains fulltext : mmubn000001_027796205.pdf (publisher's version ) (Open Access)Promotor : J. Buursink224 p