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C Paradiso

Publications and source records attributed to C Paradiso.

At least 19 recordsLinked to original sources
PubMed1995

Cervical and scalp recorded short latency somatosensory evoked potentials in response to epidural spinal cord stimulation in patients with peripheral vascular disease.

Somatosensory evoked potential (SEP) studies were performed in 14 patients with peripheral vascular disease who received epidural spinal cord stimulation (SCS) for chronic pain relief of the lower limbs. Signals were amplified and filtered between 20-2000 Hz and 200-2000 Hz to better identify activities in the high frequency range. In 7 patients bit-colour maps were also computed. In all the patients a homogeneous short-latency scalp evoked potential with a prevalent diphasic shape (P1-N1) was recorded. In all our scalp records, even with the wide bandpass, small short-latency positive deflections were observed on the descending front of the first major positive wave and they were better defined as a series of up to 6 wavelets, preceding the major negative scalp wave in the tracings filtered through the narrow bandpass. They appeared in an interval ranging from 5.5 to 15.6 msec. Bit-colour maps showed consistent positive fields, with a maximum at the vertex, starting mainly at about 5.5 msec; in 3 patients, a prominent positivity between 8.5 and 10.5 msec was recorded followed by smaller components preceding the major positive-negative (P1-N1) complex. More synchronous volleys during direct SCS produced clear short-latency SEPs. Although they were of larger amplitude, we regarded them as corresponding to those described by previous authors obtained by stimulation of nerves of the lower limbs, and probably arising from subcortical structures.

Adult↗
PubMed1995

Accuracy of interpreting human responses.

Nurse managers who advocate continuous quality improvement should be examining system-level policies, procedures and attitudes to determine whether they support or detract from accuracy of nurses' interpretations of human responses. A study discusses the relationship of accuracy of nurses' diagnoses to continuous quality improvement and demonstrates why nurse managers should focus on accuracy in system-level decisions. Four guidelines, which emphasize quality of interventions and outcomes, are given.

Humans↗
PubMed1994

Sensory neural conduction of median nerve from digits and palm stimulation in carpal tunnel syndrome.

The median sensory nerve conduction between ring finger and wrist is a suitable parameter for early detection of carpal tunnel syndrome (CTS), although shorter segments of median nerve have also been proposed for the same goal. In order to assess the relative diagnostic value of the sensory nerve conduction velocity (SNCV) of the third palmar branch versus the SNCV of the second palmar branch, generally performed until now, we studied 62 patients with typical signs and symptoms of CTS. The following parameters were evaluated by surface recording: orthodromic SNCVs in digit-wrist segments for median (index = M2, third = M3 and ring = M4 fingers), ulnar (fourth = U4 finger) and radial (thumb = R1) nerves; SNCVs in palm-wrist segments by surface bipolar stimulation at each metacarpo-phalangeal interspace (second = P2 and third = P3 for the median nerve and fourth = P4 for the ulnar nerve); and distal motor latencies of the median and ulnar nerves. No responses at the wrist were recorded in 22.6% of patients after digital stimulation of M4, whereas the SNCV of P3, the palmar nerve branch arising from digital nerves of the medial side of M3 and the lateral side of M4, was measurable in 93.5% of patients. As significantly expressed (P < 0.001) by the increased ratio of the mean values of P2 and P3 in CTS patients, the SNCV of P3 decreased more frequently and to a greater extent than the SNCV of P2.

Action Potentials↗
PubMed1994

Diagnosis of thoracic outlet syndrome. Relative value of electrophysiological studies.

The diagnostic utility of various electrophysiological techniques was evaluated in patients with thoracic outlet compression syndrome (TOCS). Our results suggest that in true neurogenic TOCS, there is no standard electrophysiological picture, but that this evolves with the severity of the syndrome. The first changes observed are electromyographic, followed by changes in F-wave and SEPs, followed finally by changes in nerve conduction parameters. EMG study was certainly more informative, showing neurogenic damage not only in limbs with neurological signs but also in about 1/4 of limbs with only subjective symptoms. The study of F-wave and SEPs does not seem to be particularly helpful, however, in view of the peculiar changes found in these patients, SEPs may be a useful complement to EMG. Nerve conduction studies were of little utility since changes in these parameters are only found in patients with long-standing anomalies and severe atrophy.

Adult↗
PubMed1994

Sex differences in surface EMG interference pattern power spectrum.

Sex differences in the spectral parameters of the surface electromyogram (EMG) power spectrum were studied during voluntary muscle contractions of different strength with rest in between. The influence of two different types of leads (unipolar and bipolar) on the values of the spectral parameters was also investigated under the same experimental conditions. The subjects were 15 healthy female and 15 healthy male volunteers. The relationship between the amplitude (root mean square) of the EMG and the force developed was not linear. The mean values of the median power frequency were lower in women than in men. With both types of lead, the increase in force was accompanied by a progressive increase in median power frequency in male and female subjects. The significant differences in spectral parameters observed in the two sexes are probably correlated with anatomic differences.

Adult↗
PubMed1994

An electromyographic evaluation of motor complications in thoracic herpes zoster.

Motor complications in thoracic herpes zoster were evaluated in 52 patients by electromyographic examination of the paraspinal muscles. At the initial EMG examination, abnormal findings were observed in 18 patients (35%). In 8 patients the myomers involved coincided in location with affected dermatomes, while in 10 patients, in addition to the involvement of myomers corresponding to affected dermatomes, there also appeared an involvement of one or more contiguous myomers not corresponding to affected dermatomes. Our study demonstrated that motor involvement in thoracic HZ is much more common than previously suggested and its incidence (35%) appears to be greater than that reported in both cervical and lumbosacral HZ.

Adult↗
PubMed1991

Brain excitability and long latency muscular arm responses: non-invasive evaluation in healthy and parkinsonian subjects.

Thirty healthy and 35 volunteers affected by Parkinson's disease (PD) were examined. Long latency responses (LLRs) and short latency somatosensory evoked potentials (SEPs) after median nerve stimulation were respectively recorded from forearm flexor muscles, and from 19 scalp electrodes, during relaxation (condition 1), light and maximal muscle contraction (conditions 2 and 3). Linear interpolation of SEPs was performed to produce isopotential colour maps. Latencies and amplitudes of the V1-V2 component in LLR, as well as of parietal, central and frontal scalp SEPs were analysed in the 3 experimental conditions. Highly significant inverse correlation matched the frontal SEP to the LLR V2 component amplitudes, both in healthy and in PD subjects. However, the V2 component--which in the former group was reliably identifiable only in condition 3--was presented in conditions 1 and 2 in a high percentage of PD subjects who also showed an abnormally reduced frontal SEP during complete relaxation. Excitability changes of brain motor areas induced by a sensory input were tested as follows: the motor cortex was transcranially stimulated (TCS) by magnetic pulses with an intensity 10% below (A) or above (B) the threshold for twitch elicitation during complete relaxation of forearm muscles; TCS was randomly preceded (range 14-32 msec) by a shock to the median or ulnar nerve at the elbow with identical characteristics as for LLR elicitation. An initial epoch of 'inhibition' followed by a peak of 'facilitation' of the amplitude of motor responses to TCS was observed when conditioning stimuli to the median nerve preceded TCS by 14-20 and by 24-32 msec, respectively. Contrary to normals, conditioning stimulation of the median nerve did not significantly influence the excitability threshold to TCS in those parkinsonians with depressed frontal N30.

Adult↗
PubMed1991

Non-invasive evaluation of central motor tract excitability changes following peripheral nerve stimulation in healthy humans.

The interval between muscle stretch and the onset of the long latency electromyographic responses (LLRs) has been theoretically fragmented into an afferent time (AT), taken at the peak of wave N20 of somatosensory evoked potentials and an efferent time (ET), calculated by means of magnetic transcranial stimulation (TCS), the two being separated by a cortical interval (CI). If this were the case, the afferent input should progressively 'energize' the sensorimotor cortex during the CI and change the excitability of cortico-spinal tracts. To investigate this, motor evoked potentials (MEPs) from thumb flexor muscles were recorded, whilst a conditioning stimulation of median or ulnar nerve randomly preceded (10-48 msec intervals) magnetic brain TCS. Nerve stimulation was adjusted to motor threshold and amplitudes of conditioned and test MEPs at different nerve-TCS interstimulus intervals were evaluated. Conditioned MEPs were significantly attenuated with nerve-TCS intervals between 16 and 20 msec for elbow and 20 and 22 msec for wrist stimulation. This was followed by MEP potentiation with nerve-TCS intervals corresponding to the sum of AT + CI (mean 23.2 msec, range 21.7-24.8). The onset latency of facilitated conditioned MEPs was about 1 msec briefer than that of test MEPs, but invariably longer than the latency of MEPs facilitated by a voluntary contraction. This protocol did not demonstrate amplitude facilitation of the segmental H reflex, corroborating the idea that the facilitated part of the conditioning nerve-TCS curve receives a transcortical loop contribution.

Adult↗
PubMed1991

'Excitability changes of muscular responses to magnetic brain stimulation in patients with central motor disorders.

The 'excitability' and 'conductivity' of motor pathways during transcranial stimulation (TCS) have been investigated in 49 patients affected by multiple sclerosis (34), amyotrophic lateral sclerosis (7), spino-cerebellar ataxia (3), primary lateral sclerosis (4) and brain metastasis (1). Hyper-reflexia, spasticity and weakness were correlated with the central motor conduction time (CCT) and with the threshold intensity of TCS required to produce a motor evoked potential (MEP). MEPs to magnetic TCS were recorded from hand and foot muscles during relaxation, contraction and after tendon vibration. Thresholds and CCTs of the patients were compared with those of 30 healthy controls. Increased threshold was found in 37 out of 49 patients (75.5%). Prolongation of the CCT was found in 38 out of 63 clinically affected upper limbs (60.3%) and in 56 out of 77 clinically affected lower limbs (72.7%). Absent motor responses to maximal TCS were found in 20 out of 98 lower limbs (20.4%). Excluding ALS patients (in whom there was a lower threshold for MEP elicitation), a significant linear correlation was found between prolonged CCT and increased threshold. While MEPs with prolonged CCTs have elevated TCS threshold, it is important to note that an elevated threshold was found in 14 out of 49 patients (28.5%) despite unchanged CCT. Spasticity and/or hyper-reflexia were more frequently associated with increased threshold than with prolonged CCT, while weakness was correlated equally well with both these parameters. In this respect magnetic TCS proves to represent a new tool for the detection of abnormal 'excitability' of the central motor tracts.

Adolescent↗
PubMed1991

Electrophysiologic evaluation of local steroid injection in carpal tunnel syndrome.

Extensive sensory and motor nerve conduction studies were performed in a series of patients with electrophysiologically proven, idiopathic carpal tunnel syndrome who were treated by a single steroid injection (40 mg of triamcinolone acetonide). Electrophysiologic studies, which included evaluation of median, ulnar, and radial orthodromic sensory action potentials, median and ulnar motor action potentials, and electromyography of two intrinsic muscles of the hand, were done before and at 45 days and six months after the treatment. By the end of the follow-up period, the symptoms had remitted completely in 11 hands (35%), 18 (58%) benefitted from partial relief, and two did not improve. In addition to the relief of symptoms, abnormalities of motor nerve conduction improved in 65% of cases, and abnormalities of sensory nerve conduction improved in 73% of all the individual digital branches of the median nerve examined. Recovery of function of the median nerve continued for a long period, even after the pharmacologic effect of the steroid agent had presumably ceased.

Action Potentials↗
PubMed1989

Single fibre motor evoked potentials to brain, spinal roots and nerve stimulation. Comparisons of the 'central' and 'peripheral' response jitter to magnetic and electric stimuli.

Single fibre motor evoked potentials to magnetic and electric non-invasive stimulation of brain, spinal cord and peripheral nerve were recorded in 8 healthy volunteers. The 'central motor jitter' and the 'peripheral motor jitter' were respectively calculated and a comparison between the magnetic and electric modalities was made. The highest degree of latency variability was observed for both magnetic and electric central motor jitter, whilst the peripheral motor jitter to nerve stimulation was as low as the neuromuscular one (range 16-60 microsecond). The magnetic 'central motor jitter' (range 94-1024 microsecond) was much larger than the electric one (range 55-280 microsecond), which was in the order of jitter calculated on H-reflex studies; moreover, the former was organized in a bi- or trimodal distribution. On the contrary, no significant differences were observed between the two modalities when the jitter to nerve stimulation was taken into account. Possible contributions of corticocortical circuitries containing several synaptic interruptions during magnetic as opposed to electric transcranial stimulation, is discussed.

Adult↗
PubMed1989

Diagnostic specificity of sensory and motor nerve conduction variables in early detection of carpal tunnel syndrome.

In the carpal tunnel syndrome (CTS) sensory nerve conduction is more sensitive than motor conduction. However, 8%-25% of the sensory distal latencies in symptomatic hands may still be normal. A systematic study was made of the median, ulnar and radial orthodromic nerve conduction velocities (SNCV) stimulating each of the fingers separately. Four SNCVs from the median nerve, two SNCVs from the ulnar nerve and one from the radial nerve were obtained, and the ratio of the median to radial SNCV and the ratios of the median and ulnar SNCVs were estimated. The significance of these parameters in the diagnosis of the CTS was studied, and a rapid technique for the screening of nerve entrapment in the initial stages of the disease is proposed. Three hundred and seventy-five symptomatic hands were examined. Seventy-five hands showed normal distal latency, in which cases, however, the SNCV of the ring finger was always outside the normal range, while the SNCVs of the thumb, index and middle fingers were abnormal in 64%, 80% and 92% of cases respectively. The amplitudes of the sensory responses were the least sensitive of the parameters studied. Our results suggest that a study of the median nerve digital branch to the ring finger may be of value in providing an easily performed and rapid technique for screening an early median nerve entrapment at the wrist.

Adolescent↗
PubMed1989

Hemofiltration: an alternative to dialysis.

Continuous arteriovenous hemofiltration (CAVH) is a relatively new procedure designed to relieve fluid overload. It has proved useful in many patients whose ability to maintain fluid homeostasis is compromised. Burn victims, patients with acute renal failure, patients with pulmonary edema, and trauma patients have all received benefit from CAVH. CAVH is an extracorporeal circuit in which blood is propelled by the force of the patient's blood pressure through a filter, ultrafiltered, and returned to the patient. CAVH removes fluid and solutes more slowly than hemodialysis, eliminating the danger of rapid fluid and electrolyte shifts. There are several ways to perform the procedure but all require intense and sophisticated medical and nursing care. Strong knowledge of fluid, electrolyte, and acid/base balance, hemodynamics, and assessment skills is required. The ability to intervene quickly and appropriately if trouble arises is a necessity. The dynamics of the treatment are discussed in detail in this article. How to deliver a safe and efficient treatment, troubleshooting guidelines, and suggestions for accurate documentation are also included.

Acute Kidney Injury↗
PubMed1988

Differences between surface EMG in male and female subjects evidenced by automatic analysis.

40 healthy volunteers (20 males and 20 females) have been studied by an automatic analysis of their surface EMG. The power density spectrum (PDS) of the electromyographic signal, derived from the tibialis anterior muscle, was used to evaluate the RMS values of the EMG developed during maximal voluntary (Vc) and evoked (Vm) contractions. The ratios between Vc, calculated over each of 5 frequency bands (5-15, 20-40, 45-70, 75-110, 115-160 Hz), and the total Vc have also been calculated. No significant differences emerge in the Vm values for males and females, whereas the Vc values for female subjects are found to be significantly reduced (P less than 0.001) with respect to the corresponding values for males. Significant differences have also been found concerning the percentage distribution of power in the above mentioned frequency bands for men and women (P less than 0.001). It can thus, be hypothesized that there are two different modalities of motor unit recruitment and that different sociological and cultural traditions may be more important in producing these differences than sexually determined physiological differences.

Adult↗
PubMed1986

Altered CSF protein pattern in a case of mycosis fungoides with nervous system involvement.

We report the clinical, neurophysiological and CSF study in a case of mycosis fungoides with nervous system involvement. The CSF contained an abnormal protein of molecular weight 22000 that was not in the patient's serum or in the CSF of control subjects and that disappeared after intrathecal immunosuppressive therapy. The nature of this protein is discussed in the light of hypothesis regarding the pathogenesis of the disease.

Cerebrospinal Fluid Proteins↗
PubMed1985

Charcot-Marie-Tooth disease: study of a large kinship with an intermediate form.

A clinical, genetic, electrophysiological and ultrastructural study of a large kinship with peroneal muscular atrophy is reported. There was a noteworthy homogeneity in the phenotype as well as in the electrophysiological characteristics encountered in 15 affected members aged between 7 and 72 years. The symptoms appeared first in the second decade of life and stabilized by the fourth decade. There was no evidence of linkage of the neuropathy gene to the Duffy blood group locus on chromosome 1. The electrophysiological data in this family as well as the ultrastructural findings confirm that there is heterogeneity in hereditary motor and sensory neuropathy type I, and support the concept of an intermediate form of Charcot-Marie-Tooth disease.

Adolescent↗