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( Headache 2012;52:792-807) Objective.- Our aim was to investigate CO2 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. [ABSTRACT FROM AUTHOR]

Our study aimed at investigating the scalp topography of ultra-late CO2 laser evoked potentials (LEPs), which are related to C fiber activation, and at exploring the effect of attention deviation on ultra-late LEPs. Brain responses to non-painful CO2 laser stimuli were recorded in ten healthy subjects in three different conditions: (i) neutral condition in which subjects did not have any task; (ii) distraction condition in which subjects were asked to perform a mathematical task; and (iii) attention condition in which subjects had to count the number of stimuli. In all subjects, also Að fiber-related late LEPs were recorded after painful CO2 laser stimulation. The ultra-late LEPs in attention condition included an earlier negative potential (ultra-late N1) in the contralateral temporal region and a simultaneous frontal positive response (ultra-late P1). Later, a vertex biphasic component (ultra-late N2a and ultra-late P2) was identifiable. The vertex ultra-late LEP amplitude was significantly decreased in both neutral and distraction condition. Ultra-late LEPs showed a longer latency than late LEPs, but the scalp distributions of both ultra-late and late LEPs were very similar, thus suggesting that the same cerebral areas may be involved in their generation. Since attention deviations have a strong effect on ultra-late LEP amplitude, the subject''s attention should be addressed to CO2 laser stimuli when ultra-late LEPs are used for clinical purposes. [Copyright &y& Elsevier]

Background: Neglect represents a severe complication of stroke, which impairs patients' daily activities. An early diagnosis of neglect is fundamental for management decisions., Aim: The aim of this study is to evaluate the usefulness of the Tinetti Test as an outcome of spatial neglect in post-stroke patients., Design: Observational retrospective data analysis., Setting: Rehabilitation Hospital., Population: Cohort of post-stroke adults admitted in our Rehabilitation Unit., Methods: One hundred and sixty stroke patients were evaluated between the 1st of January 2015 and the 31st of December 2016 at our Department. Eighty-nine inpatients matched the inclusion criteria. Their scores of the Tinetti Test for balance condition and gait function were compared with Bells Test and line bisection task for spatial neglect. Global independence activity was also assessed using Barthel Index and global cognitive functioning by means of the Mini-Mental State Examination., Results: Twenty-two patients between the 89 patients included in this study were affected by spatial neglect at admission. A high statistical significant correlation was observed between lower Tinetti scores and neglect presence (mean Tinetti Score: 2.36 neglect; 7.82 non-neglect; P<0.001)., Conclusions: The Tinetti Test is a well-established assessment scale to measure balance ability and gait function in post-stroke patients. Results from this study suggest that Tinetti Test may be considered as an early ecological screening tool for the diagnosis of neglect in post-stroke patients., Clinical Rehabilitation Impact: The alternative use of the Tinetti Test for the diagnosis of spatial neglect.

The pathophysiology of neuropathic pain in Fabry's disease (FD) is still largely unknown. Seven FD patients were studied by laser evoked potentials (LEPs) to assess the function of the A delta and C fibers. Laser pulses were delivered on the skin of the hand and perioral region at painful intensity to record LEPs related to A delta-fiber inputs and at nonpainful intensity to obtain LEPs related to C-fiber inputs. When the perioral region was stimulated, a vertex positive component was recorded with a mean latency of 260.3 ms and 376 ms after A delta- and C-fiber stimulation, respectively. The mean A delta-LEP amplitude was significantly lower in FD patients (N1/P1 mean values were 2.8 microV and 4.5 microV after hand and face stimulation, respectively, compared to 4 microV and 8.9 microV for controls; N2/P2 mean values were 8.2 microV and 11.1 microV after hand and face stimulation, respectively, and 16.7 microV and 22.3 microV in controls). Unlike the healthy subjects, 6 FD patients, suffering from neuropathic pain, showed a late positive potential related to C-fiber function (mean latency, 377.1 ms) also after facial stimulation at painful intensity, suggesting a relative overflow of C-fiber input, which may be relevant in the pathophysiology of pain in this disease.