Diagnosis Of Peripheral Nerve Disease Research Articles

Localization and Diagnostic Evaluation of Peripheral Nerve Disorders.

This article provides a framework for the initial evaluation of patients with suspected peripheral nerve disease. The key clinical elements of peripheral nerve diseases can help the practicing neurologist differentiate among peripheral neuropathies with similar presentations. The wide range of peripheral nerve diseases with similar clinical presentations can pose a diagnostic challenge. The large array of available testing modalities (including imaging and electrodiagnostic, autonomic, laboratory, biopsy, and genetic testing) further complicates clinical decision making. Recent developments (eg, discovery of new autoantibodies, genetic variations, and histopathologic techniques) across the peripheral neuropathy spectrum have resulted in an increased need to evaluate patients logically and with a tailored diagnostic approach. A careful approach that focuses on key clinical elements combined with an understanding of purposeful diagnostic testing can lead to a successful diagnosis of peripheral nerve diseases.

Review Article "Spotlight on Ultrasonography in the Diagnosis of Peripheral Nerve Disease: The Evidence to Date".

Neuromuscular ultrasound is rapidly becoming incorporated into clinical practice as a standard tool in the assessment of peripheral nerve diseases. Ultrasound complements clinical phenotyping and electrodiagnostic evaluation, providing critical structural anatomical information to enhance diagnosis and identify structural pathology. This review article examines the evidence supporting neuromuscular ultrasound in the diagnosis of compressive mononeuropathies, traumatic nerve injury, generalised peripheral neuropathy and motor neuron disease. Extending the sonographic evaluation of nerves beyond simple morphological measurements has the potential to improve diagnostics in peripheral neuropathy, as well as advancing the understanding of pathological mechanisms, which in turn will promote precise therapies and improve therapeutic outcomes.

Importance of combined use of electromyography and ultrasound in the diagnosis of peripheral nerve diseases

Electromyography (EMG) is a well known method used for many years to objectively evaluate the functions of the peripheral nervous system. It is now an indispensable part of examination of each patient with a suspicion of neuromuscular disease. It should be noted that although EMG examination provides accurate facts about the presence and severity of functional nerve damage, this method cannot provide any insight into the anatomy of the nerves, or the state of the surrounding tissue. Thus, there is a need to have additional diagnostic procedure besides EMG that would enable the full insight into a peripheral nerve. For the last two decades, there is a clear trend for more frequent use of ultrasound (US) in the diagnosis and monitoring of various diseases of the peripheral nerves. Indications for the US in peripheral nerve disorders are numerous, but this method is often applied in suspected compressive mononeuropathy, traumatic nerve damage (especially of the brachial plexus), in rare primary nerve tumors and in neurocutaneous diseases, as well as some immune-mediated neuropathies. The lecture will present the basic ultrasound principles in the diagnosis of these disorders, with illustrative examples from clinical practice.

Ultrasonography in the diagnosis of peripheral nerve disease

High-resolution ultrasound (US) of the peripheral nerves is now a standard means of assessing neuromuscular disorders in many centers. Currently used in conjunction with electrodiagnostic (EDX) studies, nerve US is especially effective in the diagnosis of entrapment neuropathies. This article reviews the basic physics of peripheral nerve US, guidelines for its current use and future directions. Advantages of using nerve US alongside EDX studies are outlined along with current limitations of testing. The role of US in the diagnosis of entrapment neuropathy is emphasized, particularly in carpal tunnel syndrome (CTS). US assisted diagnosis of peripheral nerve tumors, hereditary neuropathy and dysimmune neuropathy and traumatic injuries is also described. US is a powerful tool in the assessment of peripheral nerve disease. Nerve US is an evolving, young discipline. There is still much to learn, but current evidence supports US imaging of all patients presenting for evaluation of possible mononeuropathy. With improvements in resolution, the introduction of US contrast agents and objective measures of nerve echogenicity, there is promise for further expanding its role in the diagnosis of all peripheral neuropathies.

0482: The Clinic Value of High Frequency Ultrasound in Diagnosis of Peripheral Nerve Diseases

0482: The Clinic Value of High Frequency Ultrasound in Diagnosis of Peripheral Nerve Diseases

The clinical value of high frequency ultrasound in diagnosis of peripheral nerve diseases

To evaluate the clinical value of high frequency ultrasound in diagnosing peripheral nerve diseases (PNDs). From January 2003 to December 2006, 64 cases of PNDs were analyzed retrospectively. The ultrasound diagnosis was compared with the operative and pathological diagnosis. Based on the operative and histopathological results, in 38 patients with trauma or entrapment, 38 among 45 traumatic nerves were rightly diagnosed by ultrasound. The coincidence rate was 84.4%. In 26 patients with original peripheral nerve tumors (PNTs), including 20 neurilemmomas, 4 neurofibromas and 2 malignant neurilemmomas, 16 cases were diagnosed by ultrasound with a coincidence rate of 61.5%. The coincidence rates in limbs and trunk were 86.7% (13/15) and 27.3% (3/11) respectively. The study suggests that high frequency ultrasound can locate peripheral nerve trauma precisely, assess the impair degree correctly and provide useful information for clinic diagnosis. The high frequency ultrasound brings better diagnosis outcome in limbs nerve tumors than in trunk.

Imaging of peripheral nerve lesions.

Clinical investigations of peripheral nerve lesions routinely involve nerve conduction studies and electromyography. Imaging studies are often used to exclude focal mass lesions or external compression and to visualize muscle atrophy. More recently, it has been recognized that magnetic resonance imaging can identify changes in peripheral nerves and secondary neurogenic alterations in skeletal muscle, which may significantly enhance its use in the differential diagnosis of peripheral nerve disease. Acute axonal nerve lesions cause a hyperintense signal on T2-weighted images at and distal to the lesion site, which correlates with Wallerian degeneration and nerve oedema. Superparamagnetic iron oxide particles provide an exciting new tool to detect the invasion of macrophages into the degenerating nerve distal to an axonal lesion. Prolongation of the T2 relaxation time and gadolinium enhancement of denervated muscle develop in parallel to the development of spontaneous activity on electromyography, and are probably the consequence of capillary enlargement and increased muscular blood volume. Magnetic resonance imaging supplements the differential diagnosis of peripheral nerve disease. An advantage over clinical neurophysiological investigations is that it is operator independent and painless. It can identify axonal damage and may thus help to identify a lesion site precisely, where fractionated nerve conduction studies are not applicable. Novel contrast media may potentially be used to detect pathophysiologically relevant mechanisms such as infiltration of the nerve by macrophages. Magnetic resonance imaging also has the advantage of providing a lasting detailed topographical picture of regional variations and avoids localization errors of muscles in electromyography.

The Use of Sensory Action Potentials in the Diagnosis of Peripheral Nerve Disease

We review the different measurements that can be derived from recordings of compound sensory action potentials, and describe how less commonly measured aspects may be of use in clinical situations. In addition to the frequently obtained maximum conduction velocity and amplitude, minimum conduction velocity may be measured if near nerve electrodes and response averaging are used. Minimum conduction velocity is a sensitive measure of both axonal and demyelinating peripheral nerve pathology. Activity-dependent conduction is another aspect of sensory conduction that may provide additional information for the clinician. Refractory period of transmission has been used to diagnose subtle demyelinating lesions, as well as some axonal disorders. Supernormal period and the conduction of trains of stimuli may also be useful, although, at present, they remain predominantly research tools.

Neurographic analysis of trains of frequent electric stimuli in the diagnosis of peripheral nerve diseases. Investigations in the carpal tunnel syndrome.

Results of electromyographic and neurographic investigations in 19 patients with 24 carpal tunnel syndromes (CTS) were compared with the results obtained from 19 healthy control persons. Investigating