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Filippo Brighina

Publications and source records attributed to Filippo Brighina.

17 recordsLinked to original sources
PubMed2006

Modulatory effects of 1 Hz rTMS over the cerebellum on motor cortex excitability.

Clinical observations and data from animal experiments point to a physiological facilitatory influence of the deep cerebellar structures on the motor system through the cerebello-thalamo-cortical pathways. The aim of the present study was to explore the long-term effects of low-frequency (1 Hz) repetitive transcranial magnetic stimulation (rTMS) over the cerebellum on short intracortical inhibition (SICI) and facilitation (ICF) of the motor cortex in normal subjects. Eight healthy subjects (mean age 26.9 +/- 3.1) underwent 1 Hz frequency rTMS delivered on the right cerebellar hemisphere. Before and after cerebellar rTMS, SICI and ICF were assessed in the motor cortex contralateral to the stimulated cerebellar hemisphere by means of a paired pulse paradigm with a conditioning subthreshold stimulus set to 80% of the motor threshold (MT) followed by a testing stimulus at 120% of MT intensity. Five different interstimulus intervals (ISIs) were used to assess SICI (2 and 4 ms) and ICF (7, 10 and 15 ms). Amplitude of the responses was expressed as the percentage of motor evoked potential (MEP) to test stimulus alone. Results showed a significant decrease of ICF at 10 ms ISI that persisted up to 20 min after cerebellar rTMS. This was the only significant modulatory effect of cerebellar stimulation on intracortical motor excitability A suppressive effect of the low-frequency TMS on Purkinje cells could be supposed, even if, the lack of effects on other facilitatory ISIs, stands for more complex modulatory effects of rTMS over cerebellum. The study is a further demonstration that rTMS over the cerebellum induces a long-lasting modulatory effect on the excitability of the interconnected motor area.

Adult↗
PubMed2006

Paired pulse TMS over the right posterior parietal cortex modulates visuospatial perception.

OBJECTIVE: We previously observed a relative contralateral neglect by right parietal single-pulse TMS given 150 ms after visual stimulus presentation. Here we investigated the effects of parietal paired TMS in normal subjects performing a visuospatial task. METHODS: Thirteen right-handed healthy subjects underwent a line-length judgement task during single-pulse and paired (1, 3, 5, 10 ms ISIs) TMS, delivered on the right parietal cortex 150 ms after visual stimulus. RESULTS: Single pulse TMS over the right parietal cortex induced a significant rightward bias compared to the baseline condition. At 1 and 3 ms ISIs, paired-pulse TMS did not show any effect in comparison with single pulse TMS. More importantly, 5 ms ISI was able to restore baseline levels, thus inducing a significant improvement of the performance compared to single-pulse TMS and 1-3 ms ISIs. CONCLUSIONS: Paired TMS seems able to modulate activity of the right posterior parietal cortex in healthy subjects performing a cognitive visuospatial task.

Adult↗
PubMed2006

Hemispheric cerebellar rTMS to treat drug-resistant epilepsy: case reports.

Electrical stimulation of the cerebellar cortex by implanted electrodes has been shown to ameliorate refractory epilepsy. We investigated the potential therapeutic role of high-frequency cerebellar rTMS in patients affected by refractory epilepsy due to single or multiple foci. Six patients, three with single and three with multiple epileptic foci, underwent 20 rTMS sessions. Each session was given daily, excluding weekends, and consisted of two trains of 50 stimuli (5 Hz frequency and 90% motor threshold intensity), separated by 50s interval. rTMS was delivered through a focal coil (2 cm below and lateral to the inion) bilaterally in patients with multiple foci (two trains for hemisphere: 100 stimuli each side) and contralaterally to the epileptic focus in the others. Seizure frequency was monitored four weeks before stimulation (pre-rTMS), during the four-week treatment (rTMS) and four weeks after the treatment (post-rTMS). The rTMS over the cerebellar cortex was associated with a significant decrease of rTMS versus pre-rTMS seizure frequency both in patients with single and multiple epileptic foci. However, during the post-rTMS period seizure frequency was back to the pre-rTMS frequency. Although the results are still preliminary, they encourage further studies on larger series of patients. In particular, this rTMS approach, as compared with others, might be more useful in patients with multiple epileptic foci.

Adult↗
PubMed2006

A case study of Primary Progressive Aphasia: improvement on verbs after rTMS treatment.

This case-report shows that high frequency repetitive Transcranial Magnetic Stimulation (hf-rTMS), applied to the left prefrontal cortex, may improve the linguistic skills in Primary Progressive Aphasia (PPA). The patient's performance was evaluated on a battery of language production and memory span tasks, before and after two hf-rTMS treatments and one SHAM treatment. We observed a significant and lasting improvement of the patient's performance on verb production following the application of hf-rTMS versus Baseline and SHAM conditions. This finding suggests that hf-rTMS may directly strengthen the neural connections within an area of metabolic dysfunction and encourages the use of rTMS as an alternative therapeutic tool for neurodegenerative forms of aphasia.

Aphasia, Primary Progressive↗
PubMed2006

Improving neglect by TMS.

Hemispatial neglect refers to the defective ability of patients to explore or act upon the side of space contralateral to the lesion and to attend to stimuli presented in that portion of space. Evidence from animal models suggests that many of the behavioural sequelae associated with visual neglect may result not solely from the size of the lesion, but also from a pathological state of increased inhibition exerted on the damaged hemisphere by the contralesional hemisphere. On the basis of these potential mechanisms underlying neglect, in this review we discuss therapeutic approaches, focusing particularly on recent research using transcranial magnetic stimulation (TMS). This technique, besides representing an ideal tool to investigate visuo-spatial attentive mechanisms in humans, has shown promising beneficial effects that might have an impact on clinical practice.

Animals↗
PubMed2005

Modulatory effects of low- and high-frequency repetitive transcranial magnetic stimulation on visual cortex of healthy subjects undergoing light deprivation.

The aim of the present study was to explore further the effects of light deprivation (LD) on visual cortex excitability. Healthy subjects reporting reliable induction of phosphenes by occipital transcranial magnetic stimulation (TMS) underwent 60 min of complete LD. Phosphene threshold (PT) was measured before (T0), after 45 min (T1) and 60 min (T2) of LD, and then every 10 min after light re-exposure until recovery to T0 values. Repetitive TMS (rTMS) (at 1 or 10 Hz) was applied in separate sessions during the last 15 min of LD. PTs significantly decreased after 45 min of LD. rTMS differentially modified the effects of 60 min LD on PTs depending on stimulation frequency. One hertz rTMS did not change the decreasing of PT values as observed in baseline condition, but significantly prolonged the time to recover T0 PT values after light re-exposure. By contrast, 10 Hz rTMS significantly increased PT and the time to recover T0 PT values after light re-exposure was shortened. The results of this study show that the modulatory effects of different rTMS frequencies on visual cortex critically depend on the pre-existing excitability state of inhibitory and facilitatory circuits, and provide novel insights into the neurophysiological changes that take place in the visual cortex following functional visual deafferentation.

Adult↗
PubMed2005

A validation study of an Italian version of the ID Migraine: preliminary results.

Migraine is a highly prevalent and disabling disease that is substantially undiagnosed in primary care. Recently, the ID Migraine, a self-administered questionnaire, was shown to be a valid and reliable screener for migraine in primary care in the USA. To validate an Italian version of the ID Migraine, we planned a multicentric study, evaluating at least 220 patients affected by various form of headache. The responses to the questionnaire were compared with the diagnosis of headache made by a headache specialist blind to the result of the questionnaire. Sensitivity, specificity, and positive and negative predictive values for migraine were calculated. The statistical analysis on 140 patients now examined showed a very good performance of the ID Migraine with high sensitivity: 0.94 (95% CI: 0.89-0.95), specificity: 0.70 (95% CI: 0.54-0.86) and positive predictive value: 0.89 (0.82-0.95). If confirmed, these results would establish ID Migraine as a valid screening instrument for migraine in Italian headache patients and warrant further investigation in primary care to assess the validity of this ID screener in Italian population.

Adult↗
PubMed2005

Continuity of healthcare for headache patients: a problem of communication between headache specialists and general practitioners.

The continuous care of headache patients, from headache centres to general practice, is a managerial problem that is still unsolved in Italy. In fact, if on the one hand patients do not usually go to headache centres because of poor information, on the other hand, if they do, they do not find their general practitioner (GP) sufficiently prepared to continue the management. In Sicily we have formed a dense network of headache centres that we will try to link on the Internet to deal with the problem of poor patients information and poor specialist consultation. We also have faced the problem of the continuous care, trying to overcome "the difficulties of communication between specialists, GPs and patients" and "the difficulties of GPs in diagnostic work", by simple instruments like the Italian version of ID-Migraine, a simple three-item questionnaire.

Communication↗
PubMed2004

rTMS of the prefrontal cortex in the treatment of chronic migraine: a pilot study.

A recent fMRI study showed that dorsolateral prefrontal cortex (DLPFC) exerts an inhibitory control on pain pathways in humans. We investigated whether high-frequency rTMS over left DLPFC could ameliorate chronic migraine. Treatment consisted of 12 rTMS sessions, delivered in alternate days over left DLPFC. Sham rTMS was used as placebo. Eleven patients were randomly assigned to the rTMS (n=6) or to the placebo (n=5) treatment. Measures of attack frequency, headache index, number of abortive medications (outcome measures) were recorded in the month before, during and in the month after treatment. Subjects treated by rTMS showed a significant reduction of the outcome measures during and in the month after the treatment as compared to the month before treatment. No significant differences in the outcome measures were observed in the placebo group. High-frequency rTMS over left DLPFC was able to ameliorate chronic migraine. This is in agreement with the suggested role of DLPFC in pain control.

Adult↗
PubMed2004

Facilitatory effects of 1 Hz rTMS in motor cortex of patients affected by migraine with aura.

We previously showed paradoxical facilitatory effects of low-frequency repetitive transcranial magnetic stimulation (rTMS) on striate and extrastriate cortex of patients suffering migraine with aura. In this study we evaluated the effects of 1 Hz rTMS on the excitability of inhibitory and facilitatory circuits of motor cortex to explore whether the abnormal pattern of excitability extends beyond the sensory cortex also involving motor areas in migraine with aura. Nine patients affected by migraine with aura and eight healthy controls entered into the study. The hot spot for activation of the right abductor pollicis brevis (APB) was checked by means of a figure-of-eight coil and motor threshold (MT) recorded on this point. Nine hundred magnetic stimuli at 1 Hz frequency and 90% MT intensity were delivered at the hot spot. Before and after rTMS, intracortical inhibitory and facilitatory circuit excitability was assessed by means of a paired pulse paradigm (conditioning stimulus 80% MT and test stimulus 120% MT) with two different interstimulus intervals: 2 ms (inhibitory) and 10 ms (facilitatory). Amplitude of the responses was expressed as the percentage of motor evoked potential (MEP) to test stimulus alone. Results showed that in basal condition migraineurs present significantly reduced levels of intracortical inhibition (ICI) compared to controls. More importantly, opposite results were obtained in migraineurs with respect to controls when 1 Hz rTMS was applied. Specifically, whereas intracortical facilitation (ICF) significantly decreased in controls, it significantly increased in migraineurs. ICI levels were not significantly affected by low-frequency stimulation. Our results showed that motor as well as sensory cortex of migraine patients present an abnormal modulation of cortical excitability, where a relevant role is likely played by the inefficiency of inhibitory circuits.

Adult↗
PubMed2002

Perceptual and response bias in visuospatial neglect due to frontal and parietal repetitive transcranial magnetic stimulation in normal subjects.

Recently some authors have challenged the conventional association of directional motor neglect with damage of frontal structures, showing that pure sensory perceptual neglect (classically associated with parietal lesion) can follow damage of right frontal cortex. The aim of the present study was to assess the type of defect in visuo-spatial attention consequent upon a virtual frontal or parietal lesion induced by transcranial magnetic stimulation in normal subjects. To this purpose eleven subjects performed a visuo-spatial task requiring judgement about the length of the two segments of asymmetrically bisected horizontal lines, presented for 50 ms on a computer monitor. After each visual stimulus, subjects made a binary forced choice decision according to two different response conditions: A and B. In condition A, they had to name (right or left) the longer segment and in B the shorter segment of the line. The task was given in baseline condition and during repetitive transcranial magnetic stimulation. Trains of 10 stimuli at 25 Hz of frequency were applied over right frontal premotor and right posterior parietal areas, synchronously with visual stimuli. Parietal and frontal magnetic stimulation gave rise to significant perceptual bias as compared to baseline performance (i.e. subjects made opposite errors in the two response conditions). No significant response bias (i.e. the tendency to name the same side of the line in the two response conditions) was induced by magnetic stimulation on parietal and frontal sites. The present study highlights both the relevant contribution of frontal cortex in the determinism of neglect and the predominant role of sensory perceptual factors in parietal and frontal neglect.

Adult↗
PubMed2002

Modulation of visual cortical excitability in migraine with aura: effects of 1 Hz repetitive transcranial magnetic stimulation.

Recent studies showed hyperexcitability of the occipital cortex in subjects affected by migraine with aura. It has been shown that 1 Hz repetitive transcranial magnetic stimulation (rTMS) reduces excitability of visual cortex in normal subjects. The aim of the study was to investigate the effects of low frequency (1 Hz) rTMS on visual cortical excitability by measuring changes in phosphene threshold (PT) in subjects with migraine with aura. Thirteen patients with migraine with aura and 15 healthy controls were examined. Using a standardized transcranial magnetic stimulation protocol of the occipital cortex, we assessed the PT (the lowest magnetic stimulation intensity at which subjects just perceived phosphenes) before and after a 1-Hz rTMS train delivered at PT intensity for 15 min. The difference in the proportion of subjects reporting phosphenes in migrainer and control groups was significant (migrainers: 100% vs controls 47%; P<0.05), and 1 Hz rTMS over the occipital cortex led to a significantly increased visual cortex excitability expressed as a decrease in PT in subjects affected by migraine with aura. Conversely, after a 1-Hz TMS train normal subjects showed increased PT values, which suggests a decreased visual cortex excitability. Our findings confirm that the visual cortex is hyperexcitable in migrainers and suggest a failure of inhibitory circuits, which are unable to be upregulated by low frequency rTMS.

Adult↗
PubMedDate not supplied

Levetiracetam in the prophylaxis of migraine with aura: a 6-month open-label study.

OBJECTIVE: To evaluate the efficacy of levetiracetam as prophylactic treatment for migraine with aura with high frequency of attacks. BACKGROUND: Migraine with aura with high frequency of attacks could represent a very demanding therapeutic problem. Efficacy of the antiepileptic drug, lamotrigine, has been reported in this form of migraine. Levetiracetam is a new antiepileptic drug with an excellent tolerability profile. Mechanisms of action of this drug remain largely unknown, but recently, it has been shown to exert inhibitory effects on neuronal-type calcium channels. METHODS: We performed a small open-label trial treating 16 patients affected by migraine with aura with high frequency of attacks. After a 1-month run-in period, patients were treated with levetiracetam at a dosage of 1000 mg/d for 6 months. RESULTS: The number of attacks per month was significantly reduced during the first month (compared with run-in; P < 0.001), and it was reduced further during the second (second month vs first month; P < 0.001) and the third months (third month vs second month; P < 0.001) of the treatment. This improvement persisted unchanged for the remaining 3 months of treatment. In 7 (44%) of the 16 patients, the attacks were completely abolished after 3 months of treatment. Severity of headache and duration of headache and aura were also significantly reduced at the third and sixth months of treatment (P < 0.001). Levetiracetam was well tolerated (6 patients complained of slight dizziness, nervousness, and somnolence). CONCLUSIONS: Levetiracetam seems to be a safe and effective treatment for migraine with aura. Controlled trials are needed to confirm the observed results.

Adult↗
PubMedDate not supplied

Disappearance of haemorrhagic stroke-induced thalamic (central) pain following a further (contralateral ischaemic) stroke.

We report the case of a patient who, following a right thalamic haemorrhage, developed thalamic syndrome characterised by burning pain and hyperalgesia in the left side of the body. Three years later, following a further (contralateral ischaemic) stroke, she reported the complete disappearance of the pain and hyperalgesia. To our knowledge, this is the first described case of disappearance of thalamic syndrome following a second stroke, different in nature from and contralateral to the first. Various hypotheses, based on the nervous tracts and nuclei involved in pain processing, may be advanced to explain this occurrence.

Aged↗
PubMedDate not supplied

Headache in cerebrospinal fluid volume depletion syndrome: a case report.

Cerebrospinal fluid (CSF) volume depletion syndrome is due to leakage of cerebrospinal fluid through lesions of the dural sac at the level of the cranial base or of the spine. When past medical history is negative for recent trauma or surgery, the term spontaneous intracranial hypotension (SIH) is used. SIH is characterized clinically by orthostatic headache, neck pain, nausea, emesis, horizontal diplopia, tinnitus, plugged ear, hearing difficulties, blurring of vision, facial numbness, and upper limb radicular symptoms. In SIH, brain and cervical MR scans show a diffuse pachymeningeal gadolinium enhancement that ends at the site of CSF leakage. The application of epidural blood patches has been proposed as an effective therapy for SIH. Here we describe a case of SIH with very unusual headache features; the patient reported a paradoxical pattern of postural headache provoked by clinostatic position. The CSF leakage was identified at the convexity of the skull and headache disappeared following treatment with fluid, analgesics and steroids.

Cerebrospinal Fluid Pressure↗