Abstract Somatosensory potentials evoked by median nerve stimulation were recorded bilaterally from the prerolandic and parietal scalp in 36 patients with reversible ischemic attacks in one carotid artery distribution. Responses recorded from the affected and unaffected hemisphere were compared. SEP abnormalities were observed over the affected hemisphere in 22 subjects (61.1 %), irrespective of number and/or duration of episodes, and appeared selectively correlated to their clinical features. SEP studies proved to be more sensitive than conventional EEG recordings and are suitable for evaluation of the functional impairment of specific cerebral areas following transient cerebral ischemia. The occurence of SEP abnormalities in RIA may represent an unfavourable sign, being more frequent in patients with evidence of internal carotid artery disease.
Responses evoked over the scalp and the neck by median nerve (or finger I) stimulation were concurrently recorded in 10 subjects. It was found that the first component of the cortical SEP consists of a small amplitude polyphasic wave (S wave) which could be recorded bilaterally upon unilateral stimulation. The polarity of the S wave varied according to the reference electrode position, at variance with the P15 component which remained constantly positive. It is therefore correct to assume that different generators are responsible for these two potentials. The synchrony between the S wave and the cervical response, which is largely spinal in origin, as well as some pertinent experimental data, suggest that the S wave is a far field reflection of activity generated mainly in the cervical dorsal columns. These findings might be relevant to the diagnosis of neurological disorders.
Objectives: Recent interest has been expressed in peripheral neuropathies in hepatitis C virus (HCV) patients. The aim of this prospective study was to evaluate the prevalence of peripheral neuropathies associated with chronic hepatitis and their clinical manifestations. Patients and method: Ninety anti‐HCV‐positive patients were consecutively interviewed and examined by the same operator. Forty‐five patients with end‐stage liver disease and awaiting liver transplantation were evaluated at the Liver Transplantation Center (Group 1). Further 45 patients were referred for neurological consultation during hospitalisation in the Department of Medicine (Group 2), where they had been admitted for different clinical reasons. One patient from group 1 and 5 patients from group 2 were excluded from the study because of previous neurological diseases. All patients underwent a standardized neurological evaluation, including history, neurological examination, mini mental state examination, neuropathy symptom score, and neurological disability score. In presence of symptoms and signs of peripheral neuropathy, an electrophysiological evaluation was performed. Results: Signs or history of encephalopathy were found in 23/44 patients of group 1 (52.2%) and in 8/40 patients of group 2 (20%). Clinical manifestations of neuropathy, confirmed by electrophysiological examination, were found in 11 subjects of group 1 (25%) and in 17 patients of group 2 (42.5%). Most patients had minor symptoms; sensory disturbances occurred more frequently than motor and autonomic dysfunctions. In group 1, peripheral neuropathy was associated with systemic illness (diabetes, renal failure, liver neoplasm, previous alcohol abuse) in 4/11 patients (36.3%); conversely, in all patients from group 2, other possible etiological factors were present: alcohol abuse in 3; diabetes in 4; renal failure in 1; mixed cryoglobulinemia in 7; and neoplasm in 2. Conclusions: Symptomatic but not disabling neuropathies were found in 33% of HCV in patients. Sensory involvement was prevalent. Systemic illness and mixed cryoglobulinemia were more frequently present in Group 2 than in Group 1. This finding suggests that the metabolic dysfunctions caused by liver disease may be the primary determinant of peripheral system damage only in patients with end‐stage liver disease.
Article abstract-Hereditary neuropathy with liability to pressure palsies (HNPP) is associated with a deletion in chromosome 17p11.2, including the gene for the peripheral myelin protein 22 (PMP-22). Because of the proposal that a decreased dosage of the PMP-22 gene was the cause of HNPP, we evaluated sural nerves from eight patients with the 17p11.2 deletion and from five normal controls. The relative amount of PMP-22 mRNA was significantly lower in HNPP patients compared with normal controls (p < 0.02) using a semiquantitative reverse transcriptase-polymerase chain reaction. There was no significant decrease of P0 mRNA. Sural nerves from HNPP patients showed normal immunostaining with monoclonal antibodies against PMP-22, P0, and myelin basic protein, and only rare myelinated fibers, classified as "tomacula," showed a patchy staining of the compact myelin with monoclonal antibody against PMP-22. The significant underexpression of PMP-22 mRNA in HNPP patients compared with normal controls demonstrates that a decreased dosage of the PMP-22 gene is the most likely pathogenetic mechanism in HNPP. NEUROLOGY 1997;48: 445-449
We investigated the presence of duplication in chromosome 17p11.2 in 4 individuals with sporadic Charcot-Marie-Tooth disease (CMT 1) and 1 isolated case where a definite differential diagnosis between CMT 1 and Déjérine-Sottas disease was not achieved. The 5 affected cases and their parents and relatives were submitted to a complete clinical, neurophysiologic and genetic evaluation. A sural nerve biopsy was performed in all the isolated patients. Paternity was tested and confirmed. The presence of DNA duplication was detected in all the sporadic cases and was absent in all parents and relatives, thus confirming that a de novo dominant mutation is commonly present also in patients without a familial history and that there is a practical relevance of the genetic study in distinguishing isolated cases of CMT 1 from other forms of hereditary motor and sensory neuropathies or demyelinating neuropathies.
Sonography of the Median Nerve in Charcot-Marie-Tooth DiseaseCarlo Martinoli1, Angelo Schenone2, Stefano Bianchi3, Paola Mandich2, Claudia Caponetto2, Michele Abbruzzese2 and Lorenzo E. Derchi1Audio Available | Share
