Use, tolerability, benefits and side effects of orthotic devices in Charcot-Marie-Tooth disease.

BACKGROUND: Shoe inserts, orthopaedic shoes, ankle-foot orthoses (AFOs) are important devices in Charcot-Marie-Tooth disease (CMT) management, but data about use, benefits and tolerance are scanty. METHODS: We administered to Italian CMT Registry patients an online ad hoc questionnaire investigating use, complications and perceived benefit/tolerability/emotional distress of shoe inserts, orthopaedic shoes, AFOs and other orthoses/aids. Patients were also asked to fill in the Quebec User Evaluation of Satisfaction with assistive Technology questionnaire, rating satisfaction with currently used AFO and related services. RESULTS: We analysed answers from 266 CMT patients. Seventy per cent of subjects were prescribed lower limb orthoses, but 19% did not used them. Overall, 39% of subjects wore shoe inserts, 18% orthopaedic shoes and 23% AFOs. Frequency of abandonment was high: 24% for shoe inserts, 28% for orthopaedic shoes and 31% for AFOs. Complications were reported by 59% of patients and were more frequently related to AFOs (69%). AFO users experienced greater emotional distress and reduced tolerability as compared with shoe inserts (p<0.001) and orthopaedic shoes (p=0.003 and p=0.045, respectively). Disease severity, degree of foot weakness, customisation and timing for customisation were determinant factors in AFOs' tolerability. Quality of professional and follow-up services were perceived issues. CONCLUSIONS: The majority of CMT patients is prescribed shoe inserts, orthopaedic shoes and/or AFOs. Although perceived benefits and tolerability are rather good, there is a high rate of complications, potentially inappropriate prescriptions and considerable emotional distress, which reduce the use of AFOs. A rational, patient-oriented and multidisciplinary approach to orthoses prescription must be encouraged.

Modification of heart rate variability induced by focal muscle vibration in patients with severe acquired brain injury.

BACKGROUND/PURPOSE: Heart rate variability (HRV) is a biomarker of autonomic nervous system (ANS) reaction in persons with severe acquired brain injury (sABI) who undergo a rehabilitation treatment, such as focal muscle vibration (FMV).This study aims to evaluate if and how FMV can modulate HRV and to compare potential differences in FMV modulation in HRV between patients with sABI and healthy controls. METHODS: Ten patients with sABI and seven healthy controls have been recruited. Each individual underwent the same stimulation protocol (four consecutive trains of vibration of 5 minutes each with a 1-minute pause). HRV was analyzed through the ratio of frequency domain heart-rate variability (LF/HF). RESULTS: In the control group, after performing FMV, a significant LF/HF difference was observed in the in the second vibration session compared to the POST phase. Patients with SABI treated on the affected side showed a statistically significant LF/HF difference in the PRE compared to the first vibration session. CONCLUSION: These preliminary results suggest that FMV may modify the cardiac ANS activity in patients with sABI.

Frequency, entity and determinants of fatigue in Charcot-Marie-Tooth disease.

BACKGROUND AND PURPOSE: Fatigue, a disabling symptom in many neuromuscular disorders, has been reported also in Charcot-Marie-Tooth disease (CMT). The presence of fatigue and its correlations in CMT was investigated. METHODS: The Modified Fatigue Impact Scale (MFIS) was administered to CMT patients from the Italian Registry and a control group. An MFIS score >38 indicated abnormal fatigue. The correlation with disease severity and clinical characteristics, the Hospital Anxiety and Depression Scale and Epworth Sleepiness Scale scores, and drug use was analysed. RESULTS: Data were collected from 251 CMT patients (136 women) and 57 controls. MFIS total (mean ± standard deviation 32 ± 18.3, median 33), physical (18.9 ± 9.7, 20) and psychosocial (2.9 ± 2.4, 3) scores in CMT patients were significantly higher than controls. Abnormal fatigue occurred in 36% of the patients who, compared to patients with normal scores, had more severe disease (median CMT Examination Score 9 vs. 7), more frequent use of foot orthotics (22% vs. 11%), need of support for walking (21% vs. 8%), hand disability (70% vs. 52%) and positive sensory symptoms (56% vs. 36%). Patients with abnormal fatigue had significantly increased frequency of anxiety/depression/general distress (Hospital Anxiety and Depression Scale), somnolence (Epworth Sleepiness Scale), obesity (body mass index ≥ 30) and use of anxiolytic/antidepressant or anti-inflammatory/analgesic drugs. CONCLUSIONS: Fatigue is a relevant symptom in CMT as 36% of our series had scores indicating abnormal fatigue. It correlated with disease severity but also with anxiety, depression, sleepiness and obesity, indicating different components in the generation of fatigue. CMT patients' management must include treatment of fatigue and of its different generators, including general distress, sleepiness and obesity.

Clinical spectrum and frequency of Charcot-Marie-Tooth disease in Italy: Data from the National CMT Registry.

BACKGROUND AND PURPOSE: Data are reported from the Italian CMT Registry. METHODS: The Italian CMT Registry is a dual registry where the patient registers and chooses a reference center where the attending clinician collects a minimal dataset of information and administers the Charcot-Marie-Tooth (CMT) Examination/Neuropathy Score. Entered data are encrypted. RESULTS: Overall, 1012 patients had registered (535 females) and 711 had received a genetic diagnosis. Demyelinating CMT (65.3%) was more common than axonal CMT2 (24.6%) and intermediate CMT (9.0%). The PMP22 duplication was the most frequent mutation (45.2%), followed by variants in GJB1 and MPZ (both ~10%) and MFN2 (3.3%) genes. A relatively high mutation rate in some "rare" genes (HSPB1 1.6%, NEFL 1.5%, SH3TC2 1.5%) and the presence of multiple mutation clusters across Italy was observed. CMT4A was the most disabling type, followed by CMT4C and CMT1E. Disease progression rate differed depending on the CMT subtype. Foot deformities and walking difficulties were the main features. Shoe inserts and orthotic aids were used by almost one-half of all patients. Scoliosis was present in 20% of patients, especially in CMT4C. Recessive forms had more frequently walking delay, walking support need and wheelchair use. Hip dysplasia occurred in early-onset CMT. CONCLUSIONS: The Italian CMT Registry has proven to be a powerful data source to collect information about epidemiology and genetic distribution, clinical features and disease progression of CMT in Italy and is a useful tool for recruiting patients in forthcoming clinical trials.

Focal vibration in dysphagia: A technological treatment for severe acquired brain injury rehabilitation.

BACKGROUND: A patient with severe acquired brain injury (sABI) may experience impairment in the physiological swallowing process. Many studies in the rehabilitation field have sought to understand the effects of local vibration therapy at various levels of the central nervous system and the possible benefits in neuro-rehabilitation. There are few studies directed towards the use of vibratory energy for improving swallowing and phonatory function. OBJECTIVES: The purpose of this study is to observe the effects of integrating conventional dysphagia therapy with the focal vibration therapy in patients with sABI. METHODS: This is a pilot, randomized controlled, parallel-arm, single-blind study. Twenty-eight patients with post-sABI dysphagia were included in the study and randomized to Conventional Group (CG, conventional treatment for dysphagia) or Experimental Group (EG, conventional treatment for dysphagia plus focal vibration therapy). Patients were assessed at baseline (T0), after 4 weeks (T1) and after 8 weeks (T2) using the Dysphagia Outcome Severity Scale (DOSS) and the Bedside Swallow Assessment scale (BSAs). RESULTS: Patients in the experimental group showed a statistically significant change at T1 compared with T0 at DOSS (p = .014), and at BSAS between T1 and T2 (p = .024) and between T0 and T2 (p = .027). Overall, all patients improved significantly at DOSS between T0 and T1 (p < .001) and between T0 and T2 (p < .001). CONCLUSION: The results obtained from this pilot study are encouraging and demonstrate how the use of focal vibration therapy in add on to conventional treatment for dysphagia may be another useful tool for improving swallowing in patients with sABI.

Novel sensory paradigms for neuromodulation in disorders of consciousness in traumatic brain injury.

PURPOSE OF REVIEW: Traumatic brain injury (TBI) represents a major cause of mortality and disability worldwide. In cases of severe TBI, disorders of consciousness (DoC) can occur and therapeutic options for these conditions are few and of limited efficacy. Sensory stimulation, an instrument to improve arousal and awareness, is frequently applied in the neurorehabilitation of DoC, but scientific evidence supporting its efficacy is limited. Our aim is to review the recent literature concerning novel sensory paradigms used in sensory stimulation protocols in DoC following TBI. RECENT FINDINGS: Recent studies on sensory stimulation have investigated different types of stimulation protocols, focusing on the issue of how to demonstrate that improvements are related to the treatment applied and not to spontaneous recovery. Moreover, these studies have also shown that paraclinical tests should be useful not only to discover signs of awareness when behavioural assessment fails to do so, but also to measure the effects of sensory stimulation. SUMMARY: Future studies about novel types of sensory stimulation, whose effects should be possibly measured through paraclinical approaches, are recommended in order to increase the probability that the proper individualized stimulation is administered for each patient.

Different nerve ultrasound patterns in charcot-marie-tooth types and hereditary neuropathy with liability to pressure palsies.

INTRODUCTION: Nerve ultrasound in Charcot-Marie-Tooth (CMT) disease has focused mostly on the upper limbs. We performed an evaluation of a large cohort of CMT patients in which we sonographically characterized nerve abnormalities in different disease types, ages, and nerves. METHODS: Seventy patients affected by different CMT types and hereditary neuropathy with liability to pressure palsies (HNPP) were evaluated, assessing median, ulnar, fibular, tibial, and sural nerves bilaterally. Data were correlated with age. RESULTS: Nerve dimensions were correlated with CMT type, age, and nerve site. Nerves were larger in demyelinating than in axonal neuropathies. Nerve involvement was symmetric. DISCUSSION: CMT1 patients had larger nerves than did patients with other CMT types. Patients with HNPP showed enlargement at entrapment sites. Our study confirms the general symmetry of ultrasound nerve patterns in CMT. When compared with ultrasound studies of nerves of the upper limbs, evaluation of the lower limbs did not provide additional information. Muscle Nerve 57: E18-E23, 2018.

An exploratory study of BDNF and oxidative stress marker alterations in subacute and chronic stroke patients affected by neuropathic pain.

Patients affected by stroke, particularly subacute stroke patients, often complain of neuropathic pain (NP), which may severely impair their quality of life. The aim of this exploratory study was to characterize NP and to investigate whether there is a correlation between NP and serum brain-derived neurotrophic factor (BDNF) and serum markers of oxidative stress. We enrolled 50 patients divided in subacute (< 90 days from stroke onset) and chronic (> 90 and 180 < days from stroke onset). The Barthel Index, Deambulation Index, and Short Form 36 were used to assess the patients' degree of disability and quality of life. Pain-specific tools, namely the Numeric Rating Scale (NRS), Neuropathic Pain Diagnostic questionnaire (DN4), and Neuropathic Pain Symptom Inventory (NPSI), were also used. Serum levels of BDNF and markers of oxidative stress and of metal status were evaluated: copper, iron, transferrin, ferritin, ceruloplasmin concentration (iCp) and activity (eCp), Total Antioxidant status (TAS), Cp/Tf ratio, eCp/iCp ratio, and non-ceruloplasmin bound copper (Non-Cp Cu). We found the highest value of BDNF in subacute with NP (DN4 score ≥ 4). The TAS, Cp/Tf ratio, and eCp/iCp not only fell outside the normal reference range in a high percentage of subacute and chronic patients, but were also found to be related to specific NP symptoms. These preliminary results reveal altered BDNF and oxidative stress indices in subacute stroke patients who complain of NP. These investigative findings may shed more light on the mechanisms underlying NP and consequently lead to a more tailored therapeutic and/or rehabilitation procedure of subacute stroke patients.

Focal Mechanical Vibration Does not Change Laser-Pain Perception and Laser-Evoked Potentials: A Pilot Study.

BACKGROUND: Nonpainful tactile and electrical stimulation of the large myelinated fibers reduces spontaneous pain and the amplitude of laser-evoked potentials (LEPs), which represent the most reliable technique to assess the nociceptive pathway function. Focal mechanical vibration stimulates the Aß afferents selectively; thus, it is conceivable its action on nociceptive pathways. AIM: The aim of this study was to investigate the effect of vibratory stimuli, activating either both muscle and skin receptors or cutaneous afferents only on the LEPs and subjective laser-pain rating. METHODS: Ten healthy volunteers were studied. The subjects were evaluated in two different sessions to test muscle and skin receptors or cutaneous afferents only. In each session, LEPs were recorded to stimulation of the dorsal hand skin in radial and ulnar territory bilaterally, while the vibratory stimulus was delivered on the radial territory of the right forearm. RESULTS: The results showed a substantial stability of the potential N1 and N2/P2 after the two protocols, with a declining trend from the initial to the last test of the same session, probably due to habituation. Accordingly, the laser-pain perception did not change during the experimental setting. CONCLUSIONS: We conclude that a vibratory stimulus is ineffective in reducing the laser-evoked potentials and laser-pain perception.

Cortical inhibition of laser pain and laser-evoked potentials by non-nociceptive somatosensory input.

Although the inhibitory action that tactile stimuli can have on pain is well documented, the precise timing of the interaction between the painful and non-painful stimuli in the central nervous system is unclear. The aim of this study was to investigate this issue by measuring the timing of the amplitude modulation of laser evoked potentials (LEPs) due to conditioning non-painful stimuli. LEPs were recorded from 31 scalp electrodes in 10 healthy subjects after painful stimulation of the right arm (C6-C7 dermatomes). Non-painful electrical stimuli were applied by ring electrodes on the second and third finger of the right hand. Electrical stimuli were delivered at +50, +150, +200 and +250 ms interstimulus intervals (ISIs) after the laser pulses. LEPs obtained without any conditioning stimulation were used as a baseline. As compared to the baseline, non-painful electrical stimulation reduced the amplitude of the vertex N2/P2 LEP component and the laser pain rating when electrical stimuli followed the laser pulses only at +150 and +200 ms ISIs. As at these ISIs the collision between the non-painful and painful input is likely to take place at the cortical level, we can conclude that the late processing of painful (thermal) stimuli is partially inhibited by the processing of non-painful (cutaneous) stimuli within the cerebral cortex. Moreover, our results do not provide evidence that non-painful inputs can inhibit pain at a lower level, including the spinal cord.

Anxiety and depression in Charcot-Marie-Tooth disease: data from the Italian CMT national registry.

BACKGROUND: There is little information about neuropsychiatric comorbidities in Charcot-Marie-Tooth disease (CMT). We assessed frequency of anxiety, depression, and general distress in CMT. METHODS: We administered online the Hospital Anxiety-Depression Scale (HADS) to CMT patients of the Italian registry and controls. HADS-A and HADS-D scores ≥ 11 defined the presence of anxiety/depression and HADS total score (HADS-T) ≥ 22 of general distress. We analysed correlation with disease severity and clinical characteristics, use of anxiolytics/antidepressants and analgesic/anti-inflammatory drugs. RESULTS: We collected data from 252 CMT patients (137 females) and 56 controls. CMT patient scores for anxiety (mean ± standard deviation, 6.7 ± 4.8), depression (4.5 ± 4.0), and general distress (11.5 ± 8.1) did not differ from controls and the Italian population. However, compared to controls, the percentages of subjects with depression (10% vs 2%) and general distress (14% vs 4%) were significantly higher in CMT patients. We found no association between HADS scores and disease duration or CMT type. Patients with general distress showed more severe disease and higher rate of positive sensory symptoms. Depressed patients also had more severe disease. Nineteen percent of CMT patients took antidepressants/anxiolytics (12% daily) and 70% analgesic/anti-inflammatory drugs. Patients with anxiety, depression, and distress reported higher consumption of anxiolytics/antidepressants. About 50% of patients with depression and/or general distress did not receive any specific pharmacological treatment. CONCLUSIONS: An appreciable proportion of CMT patients shows general distress and depression. Both correlated with disease severity and consumption of antidepressants/anxiolytics, suggesting that the disease itself is contributing to general distress and depression.

Daytime sleepiness and sleep quality in Charcot-Marie-Tooth disease.

BACKGROUND: Sleep abnormalities have been reported in Charcot-Marie-Tooth disease (CMT), but data are scanty. We investigated their presence and correlation in a large CMT patients' series. METHODS: Epworth Sleepiness Scale (ESS) and Pittsburgh Sleep Quality Index (PSQI) were administered to CMT patients of the Italian registry and controls. ESS score > 10 indicated abnormal daytime somnolence, PSQI score > 5 bad sleep quality. We analyzed correlation with disease severity and characteristics, Hospital Anxiety and Depression Scale (HADS), Modified Fatigue Impact Scale (MFIS), Body Mass Index, drug use. RESULTS: ESS and PSQI questionnaires were filled by 257 and 253 CMT patients, respectively, and 58 controls. Median PSQI score was higher in CMT patients than controls (6 vs 4, p = 0.006), with no difference for ESS score. Abnormal somnolence and poor sleep quality occurred in 23% and 56% of patients; such patients had more frequently anxiety/depression, abnormal fatigue, and positive sensory symptoms than those with normal ESS/PSQI. Moreover, patients with PSQI score > 5 had more severe disease (median CMT Examination Score, CMTES, 8 vs 6, p = 0.006) and more frequent use of anxiolytic/antidepressant drugs (29% vs 7%, p < 0.001). CONCLUSIONS: Bad sleep quality and daytime sleepiness are frequent in CMT and correlated with anxiety, depression and fatigue, confirming that different components affect sleep. Sleep disorders, such as sleep apnea and restless leg syndrome, not specifically investigated here, are other factors known to impact on sleep quality and somnolence. CMT patients' management must include sleep behavior assessment and evaluation of its correlated factors, including general distress and fatigue.

Intra- and internerve cross-sectional area variability: new ultrasound measures.

INTRODUCTION: Nerve involvement in immune-related neuropathies is non-homogeneous, and therefore characterization of ultrasound (US) abnormalities is difficult. We developed two measures to quantify US abnormalities in immune-related neuropathies. METHODS: Intranerve cross-sectional area (CSA) variability for each nerve was calculated as: maximal CSA/minimal CSA. Internerve CSA variability for each patient was calculated as: maximal intranerve CSA variability/minimal intranerve CSA variability. Six patients underwent US evaluation of the median, ulnar, and fibular nerves, and the abnormalities were scored with our newly developed measures. RESULTS: The new measures were applicable to all nerves and patients. The highest degree of intra- and internerve CSA variability was observed in multifocal motor neuropathy, consistent with the asymmetric characteristics of this neuropathy. CONCLUSIONS: The application of intra- and internerve CSA variability measures allows us to quantify the heterogeneity of nerves and nerve segments and identify different US patterns in diverse immune-related neuropathies.

Habituation to pain in "medication overuse headache": a CO2 laser-evoked potential study.

OBJECTIVE: Our aim was to investigate CO(2) laser-evoked potential (LEP) habituation to experimental pain in a group of patients affected by medication-overuse headache, with a history of episodic migraine becoming chronic, before and after treatment, consisting in acute medication withdrawal and a preventive treatment cycle. BACKGROUND: One of the main features of LEPs in migraineurs is a lower habituation to repetitive noxious stimuli during the interictal phase. METHODS: LEPs were recorded to stimulation of both the right hand and the right perioral region in 14 patients and in 14 healthy subjects. The habituation of both the N1 and the vertex N2/P2 components was assessed by measuring the LEP amplitude changes across 3 consecutive repetitions of 30 trials each. RESULTS: In the 8 patients who had clinically improved after treatment, the N2/P2 amplitude habituation was significantly higher after treatment than before treatment following both hand (F = 43.2, P < .0001) and face stimulation (F = 6.9, P = .01). In these patients, the N2/P2 amplitude habituation after treatment was not different from that obtained in healthy controls (P = .18 and P = .73 for hand and face stimulation, respectively). On the contrary, in the patients who did not improve, the N2/P2 amplitude still showed reduced habituation after both hand (F = 3.1, P = .08) and face (F = 0.7, P = .4) stimulation. CONCLUSION: The deficient habituation of the vertex N2/P2 complex was partly restored after successful treatment of medication-overuse headache, reflecting a modification in pain-processing pathways.

Pain in postsurgical orthopedic rehabilitation: a multicenter study.

OBJECTIVE: The aim of this study was to quantify and characterize pain in patients undergoing lower limb postsurgical orthopedic rehabilitation and to investigate the impact of pain in slowing or interrupting their rehabilitation. DESIGN: The study was designed as a multicenter cross-sectional study. SETTING: The study was set in rehabilitation departments of the Don Gnocchi Foundation. SUBJECTS: The study subjects were the inpatients attending rehabilitation. INTERVENTIONS: There were no interventions used in the study. OUTCOME MEASURES: Pain intensity was measured with a numeric rating scale (NRS); pain characteristics were assessed with the McGill Pain Questionnaire and the ID Pain (able to discriminate nociceptive from neuropathic pain). Quality of life (QoL) was measured with the Short Form 36 Health Status Survey. A semi-structured questionnaire on pain occurrence, impact, and management was administered by the physiotherapist in charge of the patients and by the physician. RESULTS: We studied 139 patients, 82% of whom complained of at least moderate pain (NRS ≥ 3). According to ID pain, 45.6% patients complained of probable (33.8%) or highly probable (11.8%) neuropathic pain. A higher pain intensity was significantly related to the probability of having neuropathic pain (P < 0.001). Patients with more severe pain reported lower physical and mental QoL scores. In 38.6% of cases, pain interfered with the rehabilitation process, and in 18.5% it was the cause of physical therapy discontinuation. CONCLUSIONS: In light of the high occurrence and intensity of pain in the sample, and of the significant impact on the rehabilitation program, clinicians should pay more attention to pain, especially neuropathic pain, in postsurgical patients. Tailored pain pharmacological therapy could possibly improve patient compliance during the rehabilitation process and enhance long-term outcomes.

Role of Sport Activity on Quality of Life in Charcot-Marie-Tooth 1A Patients.

The present study aims to investigate the benefits induced by physical activity/practiced sport in Charcot-Marie-Tooth 1A (CMT1A). Patients were divided into sport and no-sport groups according to their sports performance habit. Thirty-one patients were enrolled, of which 14 practiced sports and 17 did not. Clinical assessments were administered to evaluate disability, self-esteem, depression, quality of life, and pain. Statistical analysis revealed significant differences in terms of gender in the no-sport group compared to the sport group (p = 0.04). Regarding the quality of life, physical function (p = 0.001), general health (p = 0.03), social function (p = 0.04), and mental health (p = 0.006) showed better patterns in the sport group than no-sport group. Moreover, neuropathic pain was reduced in the sport group according to the Neuropathic Pain Symptom Inventory (p = 0.001) and ID-PAIN (p = 0.03). The other administered questionnaires showed no significant differences. Our study confirms that CMT1A patients, who practice sports, with a similar severity of disability, may have a better physical quality of life while suffering less neuropathic pain than their peers who do not practice sports. Results recommend the prescription of sport in CMT1A patients.

Severe Acquired Brain Injury: Prognostic Factors of Discharge Outcome in Older Adults.

Severe Acquired Brain Injury (sABI) is a leading cause of disability and requires intensive rehabilitation treatment. Discharge from the rehabilitation ward is a key moment in patient management. Delays in patient discharge can adversely affect hospital productivity and increase healthcare costs. The discharge should be structured from the hospital admission toward the most appropriate environment. The purpose of our study is to investigate early predictors of outcome for discharge in older adults with sABI. A retrospective study was performed on 22 patients who were admitted to an intensive neurorehabilitation unit between June 2019 and December 2021. Patients were divided into two outcome categories, good outcome (GO) or poor outcome (PO), based on discharge destination, and the possible prognostic factors were analyzed at one and two months after admission. Among the factors analyzed, changes in the Disability Rating Scale (DRS) and Level of Cognitive Functioning (LCF) at the first and second month of hospitalization were predictive of GO at discharge (DRS, p = 0.025; LCF, p = 0.011). The presence of percutaneous endoscopic gastrostomy at two months after admission was also significantly associated with PO (p = 0.038). High Body Mass Index (BMI) and the presence of sepsis at one month after admission were possible predictors of PO (BMI p = 0.048; sepsis p = 0.014). An analysis of dynamic predictors could be useful to guarantee an early evaluation of hospital discharge in frail patients with sABI.

Ultrasound evaluation of peripheral neuropathy in POEMS syndrome.

INTRODUCTION: Polyneuropathy, organomegaly, endocrinopathy, M protein, skin changes (POEMS) syndrome is a rare multisystem disorder associated with plasma cell dyscrasia whose main neurological feature is a demyelinating polyneuropathy. The aim of our study was to assess the pattern of ultrasound (US) nerve abnormalities in POEMS syndrome patients. METHODS: Eight POEMS syndrome patients underwent neurological examination and US evaluation of the median, ulnar, fibular, tibial, and sural nerves. Nerve cross-sectional area and echogenicity abnormalities were analyzed. RESULTS: US abnormalities were mostly localized at entrapment sites. Enlargements outside the entrapment sites were uncommon. No correlation was found between muscle weakness and focal US findings. CONCLUSIONS: No specific pattern of US abnormalities was identified in this cohort of patients with POEMS syndrome. The lack of correlation between US and clinical findings may be secondary to the chronic nerve damage that is common in POEMS syndrome, where the diagnosis is often delayed.

Single-fiber conduction velocity test allows earlier detection of abnormalities in diabetes.

INTRODUCTION: The purpose of this study was to determine whether single-fiber conduction velocity (SF-CV) of a small number of axons increases sensitivity for identification of motor nerve conduction alterations in patients with diabetes. METHODS: Twenty-one consecutive diabetic patients in good metabolic control were studied. For each patient, conventional (C-CV) and SF-CV results were correlated with the presence of neuropathic symptoms. RESULTS: Nine of 21 patients reported symptoms suggestive of mild nerve impairment. Three patients had abnormal sural nerve CV, 1 of whom also had abnormal motor nerve conduction. Eighteen patients had normal findings on conventional tests, 3 of whom had slowing of SF-CV. CONCLUSIONS: SF-CV is able to detect mild myelin damage with higher sensitivity than conventional tests. The use of SF-CV may be a helpful tool in the early identification of diabetic polyneuropathy, and it may be useful for tailoring an approach to diabetic polyneuropathy.