D. Buffa

Contralateral neglect induced by right posterior parietal rTMS in healthy subjects.

&NA; We applied repetitive transcranial magnetic stimulation (rTMS) in order to induce interference on visuo‐spatial perception in 11 healthy subjects. Subjects performed a visuo‐spatial task requiring judgements about the symmetry of prebisected lines. Visual stimuli consisted of symmetrically or asymmetrically transected lines, tachystoscopically presented for 50 ms on a computer‐monitor. Performance was examined in basal condition and during rTMS trains of 10 stimuli at 25 Hz, delivered through a focal coil over right or left posterior parietal cortex (P5 and P6 sites) and triggered synchronously with visual stimulus. Randomly intermixed sham rTMS trains were employed to control for non‐specific effects. Right parietal rTMS induced a significant rightward bias in symmetry judgements as compared with basal and sham rTMS conditions. No differences emerged between other conditions.

rTMS of the unaffected hemisphere transiently reduces contralesional visuospatial hemineglect

To verify the role of interhemispheric influences on manifestations of neglect, the authors investigated the effects of a transient repetitive transcranial magnetic stimulation (rTMS)-induced disruption of the unaffected hemisphere on contralesional visuospatial neglect in two left- and five right-brain-damaged patients. Parietal rTMS of the unaffected hemisphere during the execution of a computerized task of bisected line’s length judgment transiently decreased the magnitude of neglect as expressed in the number of errors.

A Case-Control Study on Cigarette, Alcohol, and Coffee Consumption Preceding Parkinson’s Disease

Objective: To investigate the association between cigarette smoking, alcohol drinking, coffee consumption and Parkinson’s disease (PD). Methods: We selected subjects affected by idiopathic PD, with a Mini-Mental State Examination of ≧24, and controls matched 1 to 1 with cases by age (± 2 years) and sex. Controls were randomly selected from the resident list of the same municipality of residence of the cases. We assessed cigarette smoking, alcohol drinking, and coffee consumption preceding the onset of PD or the corresponding time for controls using a structured questionnaire, which also evaluated the duration and dose of exposure. Using conditional logistic regression analysis, we calculated adjusted OR and 95% CI. Results: We interviewed 150 PD patients and 150 matched controls. Cigarette smoking (ever vs. never smokers OR = 0.66, 95% CI = 0.41–1.05, p = 0.08) did not show a statistically significant association with PD. We observed an inverse association between alcohol drinking (ever vs. never OR = 0.61, 95% CI = 0.39–0.97, p = 0.037) and coffee consumption (ever vs. never OR = 0.16, 95% CI 0.05–0.46, p = 0.0001) and PD. These associations remained significant after adjustment for other covariates: OR for ever vs. never alcohol consumption was 0.62 (95% CI = 0.43–0.89, p = 0.009) and that for coffee drinking 0.19 (95% CI = 0.07–0.52, p = 0.001). Heavy coffee consumption confirmed the inverse association between coffee and PD (more than 81 cup/year vs. none: OR = 0.20, 95% CI = 0.08–0.47, p ≤ 0.0001). Conclusions: Consistent with previous studies, our results suggest an inverse association between coffee drinking, alcohol consumption and PD. The multiple inverse association observed may indicate a complex interaction between genetic and environmental factors.

Prevalence and risk factors of post-polio syndrome in a cohort of polio survivors☆

OBJECTIVE To investigate frequency and associated factors of post polio syndrome (PPS) in an Italian cohort of people with prior poliomyelitis. METHODS We screened subjects admitted for poliomyelitis at the paediatric hospital of the University of Palermo during the time frame 1945-1960. Patients who developed PPS were identified through a structured questionnaire and a neurologic examination. PPS diagnosis was made according to specified diagnostic criteria. Frequency of PPS was calculated in the selected cohort of polio survivors. The association with the investigated risk factors (sex, age at onset of polio, extension and severity of polio, education, associated diseases, cigarette smoking, trauma, polio vaccination) was analysed by the calculation of the odds ratio. RESULTS Forty-eight participants met the adopted diagnostic criteria for PPS, giving a prevalence of 31.0%. The prevalence rate was significantly higher in women than in men (p=0.02). Logistic regression analyses revealed a significant inverse association with onset of poliomyelitis at over 12 months of age (OR 0.33; CI 0.14-0.79) a higher degree of education (OR 0.20; CI 0.07-0.79), and a significant association with the presence of other diseases (OR 9.86; CI 3.69-26.34). CONCLUSIONS In our survey one-third of patients with prior poliomyelitis had PPS. Higher age at onset of poliomyelitis is inversely associated with PPS. The association with other diseases may indicate that a chronic physical stress, particularly in already weak motor units, can contribute to the development of signs and symptoms of PPS. Our results also suggest the impact of socio-economic conditions on the risk of PPS.

A transcranial magnetic stimulation study evaluating methylprednisolone treatment in multiple sclerosis.

Objective– To investigate the efficacy of two different high doses of intravenous methylprednisolone (IVMP) during Multiple Sclerosis (MS) relapses. Background– Transcranial Magnetic Stimulation (TMS) is the most sensitive neurophysiological ascertainment to quantify motor disability, to follow the recovery from an MS relapse, and to detect the response to treatment. Design and method– Twenty‐four clinically definite relapsing – remitting MS patients presenting a relapse were randomly assigned to a treatment for 5 days with IVMP 1 or 2 g/day. The response to treatment of each patient was evaluated through Expanded Disability Status Scale (EDSS), Medical Research Council (MRC) score, and TMS by means of motor evoked potential (MEP) parameters. Results– Motor threshold (MT), central motor conduction time (CMCT) and MRC showed a higher improvement with the highest dose of IVMP. Silent period and EDSS improved with both treatments. Conclusion– The dose of 2 g/day of IVMP is more effective in MS relapse.

Reorganization of cortical motor area in prior polio patients

OBJECTIVE Focal transcranial magnetic stimulation (TMS) was used to study the motor maps of upper limb muscles in 7 adult patients with a history of paralytic poliomyelitis. The aim of the study was to verify the potential for long-term cortical reorganization of a selective peripheral motor neuron lesion suffered early in life. METHODS Patient selection was based on the prevalent involvement of proximal muscles in only one of the upper limbs. Motor evoked potentials (MEPs) were recorded from deltoid and abductor pollicis brevis (APB) muscles. Each muscle map was characterized by area (no. of excitable positions), volume (the sum of MEP amplitudes at all scalp positions), maximal amplitude (the highest MEP recorded). RESULTS In the patients, the mean area, volume and maximal amplitude were significantly greater in affected vs. contralateral deltoid (P<0.05) and vs. controls (P<0.01). No significant differences were found in APB map parameters. The APB/deltoid ratio for area was lower in the affected compared with the unaffected side and controls (P = 0.06). Cortical reorganization was not significantly correlated with motor performance. CONCLUSION These findings are consistent with a rearrangement in human motor pathways targeting muscles affected by a lower motor neuron lesion.

Magnetic stimulation study in patients with myotonic dystrophy

To further define motor nervous system alterations in myotonic dystrophy (MD), motor potentials to transcranial and cervical magnetic stimulation (MEPs) were recorded from the right abductor pollicis brevis muscle in 10 patients with MD and in 10 healthy controls. Cortical and cervical latencies, central motor conduction time (CMCT), stimulus threshold intensity and cortical MEP amplitudes expressed both as absolute values and as %M were analysed. MEP cervical latency, absolute or relative amplitude and excitability threshold did not significantly differ in patients and controls. The mean cortical motor latency and CMCT were significantly prolonged in MD patients with respect to normal subjects. Moreover, CMCTs were found to be significantly related to stimulus threshold intensity (P = 0.03) and only marginally related to absolute cortical amplitude (P = 0.06). These findings are indicative of a central motor delay, also related to decreased excitability of motor neurons, in patients with MD. No correlations were found between individual neurophysiological parameters and age, duration of disease and clinical impairment. Our results suggest that magnetic stimulation studies can detect subclinical dysfunctions of the central motor system in MD patients, as one of the multisystemic manifestations of the disease, rather independent of the primitive muscle damage.

Evoked potential study in facio-scapulo-humeral muscular dystrophy

Nerve conduction velocities (NCVs), somatosensory (SEPs) and auditory evoked potentials (BAEPs) were recorded in 9 patients with facio‐scapulo‐humeral dystrophy (FSHD) and in 20 age‐matched controls. In FSHD patients a significant increase of the nerve distal sensory latencies and of the absolute SEP latencies revealed a subclinical involvement of the afferent sensory pathways, as well as the abnormal slowing of the later components of the BAEPs, pointed to a central auditory dysfunction. Moreover all patients underwent brain MRI that showed the presence of white matter hyperintense lesions in 4 of them (44%). No correlations were found between individual or total number of SEP and BAEP abnormal electrophysiological parameters and severity of WMHL, age, age at onset, duration of the disease or muscular impairment. These findings make the interpretation and pathophysiology of the nervous damage in FSHD rather uncertain. More studies are required to better define the aspects of neurogenic involvement in this type of muscular dystrophy.

Juvenile Migraine and Allodynia: Results of a Retrospective Study

There are only 2 small sample studies investigating allodynia in the pediatric population. The aim of this study was to evaluate the frequency of allodynia during cephalalgic attacks in a juvenile population with primary headaches and its association with other symptoms of migraine.