R Massini

Fondazione Salvatore Maugeri IRCCS, Pavia, Lombardy, Italy

Are you R Massini?

Claim your profile

Publications (12)45.43 Total impact

  • Article: Percutaneous stimulation of mechanoreceptors and peripheral neural transmission in normal subjects and patients with hereditary ataxias.
    Electroencephalography and clinical neurophysiology. Supplement 02/1999; 50:156-66.
  • Article: Subclinical peripheral nerve involvement in patients with rheumatoid arthritis.
    [show abstract] [hide abstract]
    ABSTRACT: Clinical involvement of the peripheral nervous system is uncommon in rheumatoid arthritis (RA); the most common disorders are multiple mononeuritis, sensorimotor neuropathy, and entrapment neuropathy. This study was undertaken to investigate the occurrence of electrophysiologically evident peripheral nerve involvement in RA patients without a clinical history of peripheral nerve involvement. Forty RA patients were examined neurologically and electrophysiologically, and sural nerve biopsies were performed in 4. No patient reported symptoms or signs of peripheral nerve involvement. Twenty-six patients (65%) exhibited electrophysiologic findings consistent with a sensorimotor neuropathy (in 2 of them a carpal tunnel syndrome was also present), while 3 patients showed isolated carpal tunnel syndrome. There was a moderate loss of myelinated fibers in 3 of the 4 nerve biopsy samples, and all showed an increased number of endo- and perineurial vessels and some signs of axonal degeneration. Patients with RA may have electrophysiologic and histologic findings of peripheral nerve damage, even in the absence of clinical evidence of peripheral nerve involvement.
    Arthritis & Rheumatism 08/1998; 41(7):1196-202. · 7.87 Impact Factor
  • Article: Variations of perineurial thickness in peripheral neuropathies.
    Muscle & Nerve 07/1994; 17(6):696-7. · 2.37 Impact Factor
  • Article: Median nerve sensory responses evoked by tactile stimulation of the finger proximal and distal phalanx in normal subjects.
    [show abstract] [hide abstract]
    ABSTRACT: We compared the characteristics of near-nerve recorded sensory potentials elicited in response to electrical stimulation of digital nerves versus tactile stimulation of the digital skin in 17 healthy subjects with a mean age of 26 years. We also calculated the density of Meissner's corpuscles in the distal and proximal phalanx of digit III of 6 males who had suffered a violent death, but were free from diseases of the peripheral nerve system. Responses to tactile stimulation had a longer latency and lower amplitude than responses to electrical stimulation. Unlike electrically elicited responses, responses to tactile stimulation, which consisted of six or seven main spike components plus several minor components, were similar in recordings from the wrist and elbow. However, with proximal stimulation the electrically evoked responses were more compact and had a higher amplitude and area, whereas the tactile evoked potential became significantly reduced in maximum amplitude and cumulative area. The differences in sensory conduction between distal and proximal could reflect activation of a larger number of nerve fibers when electrical stimuli are used and a smaller amount of mechanoreceptors when tactile stimuli are used.
    Muscle & Nerve 04/1994; 17(3):269-75. · 2.37 Impact Factor
  • Article: Sensory nerve findings by tactile stimulation of median and ulnar nerves in healthy subjects of different ages.
    [show abstract] [hide abstract]
    ABSTRACT: We studied orthodromic sensory conduction velocity along the distal and proximal segments of the median and ulnar nerves by tactile stimulation of the distal phalanx of the 3rd and 5th digits in 44 healthy subjects divided into 2 age groups: from 16 to 35 years and from 63 to 81 years. In the same nerves, we used selective electrical stimulation of the corresponding digital nerves to obtain sensory potentials. In both groups, responses to tactile stimuli had a longer latency and smaller amplitude than those to electrical stimulation, and they were distributed in a series of 6-7 main deflections, apparently regardless of whether the recording site was distal or proximal. Moreover, irrespective of the nerve and of subject age, conduction velocity along both the digit-wrist and the wrist-elbow nerve segments was significantly slower with tactile stimuli than with electrical stimuli. However, independently of the stimulus used, conduction velocity along the proximal nerve segment was significantly faster than that measured along the digit-wrist nerve segment. In both the median and ulnar nerves, maximum potential amplitude, cumulative area and conduction velocity were significantly reduced in the older age group. This finding could reflect the smaller number of Meissner's corpuscles in older subjects, and the loss of large nerve fibres in individuals over 60.
    Electroencephalography and Clinical Neurophysiology 01/1994; 89(6):392-8.
  • Article: The relationship between electrophysiological findings, upper limb growth and histological features of median and ulnar nerves in man.
    [show abstract] [hide abstract]
    ABSTRACT: In 19 median and 10 ulnar nerves of 28 healthy young volunteers, the maximum orthodromic sensory conduction velocity was studied along one or two fingers (the third and/or the fifth), the palm, and the forearm. In five 20 to 32-yr-old males and in a newborn male, post-mortem samples of either the median or the ulnar nerve were obtained from the finger (either the third or the fifth), the palm, the wrist and the forearm in order to study the size distribution of external fibre and axon diameters, and the fibre internodal length. In 2374 infants, children and adolescents, the height, length of both the third and the fifth finger, length of the palm, and length of the forearm were measured. The results showed (i) a significantly slower conduction velocity along the fingers; (ii) a significantly shorter internodal length without remarkable fibre diameter changes in the same nerve segments; (iii) a significantly smaller elongation of these body parts; (iv) a significant correlation between these data. In conclusion, internodal length seems to play an important role in governing conduction velocity of myelinated peripheral nerve fibres.
    Brain 01/1993; 115 ( Pt 6):1925-45. · 9.46 Impact Factor
  • Article: Electrophysiological and histological follow-up study in 15 Friedreich's ataxia patients.
    [show abstract] [hide abstract]
    ABSTRACT: A clinical and electrophysiological follow-up was carried out for 3 to 7 years on 15 patients with Friedreich's ataxia (FA). Sural nerve biopsy was performed once in all patients, and a second time 6-7 years later in three of them. Clinical worsening and progression of disturbance were evaluated according to IAP and IACR scales. Sensory orthodromic conduction along median and tibial nerves was typical of FA and did not change between first and last examinations, nor were there morphological changes between the first and the second sural nerve biopsies. Peripheral nerve involvement is thought to be a result of defective development of the largest neurons and to remain stable from a very early stage of the disease; the clinical worsening may then be due to a progressive involvement of the pyramidal tracts and the cerebellar pathways.
    Muscle & Nerve 07/1990; 13(6):536-40. · 2.37 Impact Factor
  • Article: [Death dating by the study of nerve fibre demyelination of the median nerve].
    Acta medicinae legalis et socialis 02/1988; 38(1):63-9.
  • Article: Is the sensory neuropathy in ataxia-telangiectasia distinguishable from that in Friedreich's ataxia?
    [show abstract] [hide abstract]
    ABSTRACT: The bioptical morphometric and ultrastructural study of sural nerve in a 17-year-old boy with ataxia-telangiectasia (AT) is reported. Our findings include a loss of fibers, particularly of large ones, axonal degenerative changes, Schwann cell inclusions of various type, and rare signs of primary demyelination. Teased-fiber study showed paranodal myelin enlargements, segmental demyelination, shortening, and/or variability of internodal length. This picture is similar to that in Friedreich's ataxia (FA), although they differ in degree and time of onset. A correct neuropathologic diagnosis of AT cannot be made on the basis of sural nerve biopsy alone.
    Acta Neuropathologica 08/1986; 69(3):213-219. · 9.32 Impact Factor
  • Article: Is the sensory neuropathy in ataxia-telangiectasia distinguishable from that in Friedreich's ataxia? Morphometric and ultrastructural study of the sural nerve in a case of Louis Bar syndrome.
    [show abstract] [hide abstract]
    ABSTRACT: The bioptical morphometric and ultrastructural study of sural nerve in a 17-year-old boy with ataxia-telangiectasia (AT) is reported. Our findings include a loss of fibers, particularly of large ones, axonal degenerative changes, Schwann cell inclusions of various type, and rare signs of primary demyelination. Teased-fiber study showed paranodal myelin enlargements, segmental demyelination, shortening, and/or variability of internodal length. This picture is similar to that in Friedreich's ataxia (FA), although they differ in degree and time of onset. A correct neuropathologic diagnosis of AT cannot be made on the basis of sural nerve biopsy alone.
    Acta Neuropathologica 02/1986; 69(3-4):213-9. · 9.32 Impact Factor
  • Article: Correlations between clinical, electrophysiological and histological findings in patients with different diseases of the peripheral nervous system.
    The Italian Journal of Neurological Sciences 01/1984; 4(4):511.
  • Article: Friedreich's ataxia: electrophysiologic and histologic findings in patients and relatives.
    [show abstract] [hide abstract]
    ABSTRACT: Peripheral nerve conduction velocity and cortical evoked potentials were investigated in 48 patients with Friedreich's disease and in 35 relatives. There were 14 patients and 2 relatives who underwent sural nerve biopsy. In the patients sensory conduction velocity was moderately slowed, whereas sensory responses were markedly reduced. Nerve biopsy showed a severe loss of large myelinated fibers and no demyelination. On teased nerve fiber preparations, most fibers presented uniformly short internodes. No correlation was seen between sensory conduction findings or histologic abnormalities and clinical disability. In patients SSEP changes, which were constant, and VEPs, which were frequently involved, were unrelated to the severity or duration of clinical disability. There were 14 relatives who showed clinical signs of Friedreich's disease. Slightly decreased distal conduction velocity along sensory fibers was observed in more than half of the relatives. Nerve biopsy was noncontributory. In conclusion, we could not determine whether the abnormalities observed in the siblings were an expression of a heterozygotic condition, or whether they were early signs of the disease.
    Muscle & Nerve 10(6):503-15. · 2.37 Impact Factor