Heart rate variability in Parkinson's disease unaffected by deep brain stimulation.

OBJECTIVES: Our aim was to investigate the impact of subthalamic nucleus deep brain stimulation (STN-DBS) on the cardiovagal control of patients with advanced Parkinson's disease. MATERIALS AND METHODS: Twenty-four patients (mean age: 62.1 ± 9.4 years) were examined 3 days before and 6 months after DBS by a questionnaire, blood pressure monitoring and a battery of neurophysiological tests: time domain analysis of RR interval variation during normal and deep breathing (DB), Valsalva manoeuvre, and tilt test. By off-line, performed frequency domain analysis of heart rate variation, total power (TP), low frequency band (LF) band, high-frequency (HF) band, and their normalized units were estimated. The neurophysiological measurements were compared to those of 24 healthy controls. RESULTS: The values of time domain variables were pre- and postoperatively lower in patients than in controls. A significant reduction was found in LF band after the implantation. Orthostatic hypotension was present in 45.8% of the patients preoperatively and 12.5% postoperatively. There was no correlation between DBS-related changes of motor function and corresponding neurophysiological measurements, but patients with more than 60% motor improvement had higher time domain parameters' values than the others. CONCLUSIONS: STN-DBS offered no considerable impact on autonomic cardiovascular control.

Deep brain stimulation for secondary dystonia: results in 8 patients.

BACKGROUND: Dystonia is a medically intractable condition characterized by involuntary twisting movements and/or abnormal postures. Deep Brain Stimulation (DBS) has been used successfully in various forms of dystonia. In the present study, we report on eight patients with secondary dystonia, treated with DBS in our clinic. METHOD: Eight patients (five males, three females) underwent DBS for secondary dystonia. The etiology of dystonia was cerebral palsy (n = 2), drug-induced (n = 1), post encephalitis (n = 2) and postanoxic dystonia (n = 3). The functional capacity was evaluated before and after surgery with the use of Burke-Fahn-Mardsen Dystonia Rating Scale (BFM scale), both movement and disability scale (MS and DS, respectively). The target for DBS was the globus pallidus internus (GPi) in 7 patients and in one patient, with postanoxic damaged pallidum, the ventralis oralis anterior (Voa) nucleus. Brain perfusion scintigraphy using Single Photon Emission Computed Tomography (SPECT) was performed in two separate studies for each patient, one in the "off-DBS" and the other in the "on-DBS" state. FINDINGS: Postoperative both MS and DS scores were found to be significantly lower compared to preoperative scores (p = 0.018 and p = 0.039, respectively). Mean improvement rate after DBS was 41.4% (0-94.3) and 29.5% (0-84.2) in MS and DS scores, respectively. The SPECT Scan, during the "on-DBS" state, showed a decrease in regional cerebral blood flow (rCBF), compared to the "off-DBS" state. CONCLUSIONS: Our results seem promising in the field of secondary dystonia treatment. More studies with greater number of patients and longer follow-up periods are necessary in order to establish the role of DBS in the management of secondary dystonia. Finally, the significance of brain SPECT imaging in the investigation of dystonia and functional effects of DBS should be further evaluated.

Co-occurrence of brain tumours and demyelination of the central nervous system: coincidence or interrelation?

The co-occurrence of a brain tumour and demyelinating disease of the central nervous system (CNS) constitutes a rare clinical entity. We herein report the incidence of meningioma and CNS non-specific demyelination in a patient with a 6-year history of operated brain tumour (meningioma). Our case bolsters the argument that in at least some cases, the occurrence of a brain tumour could predispose to CNS non-specific demyelination.

In-hospital direct cost of acute ischemic and hemorrhagic stroke in Greece.

OBJECTIVES: The geographic inequity and the wide variation in the patterns of care of stroke found across Europe together with the lack of health economics evaluation in Greece led to this prospective study, aiming to provide data on in-hospital direct cost of patients with an acute stroke in Greece, and to identify independent prognostic factors. METHODS: Demographic and clinical data were recorded on 429 consecutive patients with an acute ischemic or hemorrhagic stroke admitted to a tertiary care hospital in Greece during a period of 18 months. The costs incurred were estimated using the official financial charts listing in euro (euro), the real expenditure of all hospital departments. RESULTS: The direct in-hospital cost for all stroke cases was 1,551,445euro for a total of 4674 days (331.9euro per day in-hospital). The mean in-hospital cost per stroke patient was 3624.9euro (+/-2695.4). Hemorrhagic strokes were significantly more expensive than the ischemic strokes [mean 5305.4 (+/-4204.8)euro and 3214.5 (+/-1976.2)euro, respectively) and lacunar strokes the least expensive among ischemic stroke subtypes. The length of stay was highly correlated with in-hospital total cost. Multivariate linear regression analysis showed that admission ward, stroke severity on admission, stroke type and status discharge were independent predictors of cost. CONCLUSIONS: Purchasers in our health services should differentiate in their cost estimates and pricing schemes between types of cerebrovascular events. Future studies should focus on modifiable factors related, not only with stroke characteristics, but also with operational policies of hospitals, that may influence length of stay.

Clinical and electrophysiological features of peripheral neuropathy induced by administration of cisplatin plus paclitaxel-based chemotherapy.

The current prospective study sought to trace the incidence and severity of cisplatin plus paclitaxel (DDP+P)-induced neuropathy and to determine its clinical and electrophysiological pattern. Furthermore, it was attempted to describe its evolution by following up the course of peripheral neuropathy (PN) during chemotherapy as well as 3 months after its discontinuation. Thirteen adult patients scheduled to be treated with six courses of cumulative DDP+P-based regimens for a non-myeloid malignancy participated in this study. These patients were clinically and electrophysiologically monitored at baseline, during chemotherapy and 3 months after its discontinuation. The severity of PN was summarized by means of a modified PN score. Evidence of PN was disclosed in nine of the 13 patients (69.2%). The mean PN score for patients that manifested some grade of PN was 17.3 +/- 6.1 (range 9-28). All longitudinal comparisons concerning the motor conduction velocities (MCV) variables failed to reach significance. By contrast, comparisons of the mean changes at baseline and each of the follow-up studies revealed a significant decrease in all sensory action potentials examined. The follow-up evaluation performed 3 months after the discontinuation of chemotherapy showed that the DDP+P-induced neuropathy persists and progresses over time. Our results indicate that the majority of patients treated with a DDP+P-based regimen at full dose intensities would manifest an axonal, predominately sensory PN, of mild to moderate severity, which would persist for several months after the discontinuation of chemotherapy.

Dynamic F wave study in patients suffering from peripheral arterial occlusive disease.

OBJECTIVE: To prospectively detect significant transient F wave abnormalities obtained after exercise in patients with peripheral arterial disease (PAD) and to assess the potential diagnostic sensitivity of dynamic F wave study in such a context. PATIENTS AND METHODS: A series of 40 electrical stimuli were delivered to the peroneal and the posterior tibial nerves of 25 patients with PAD in order to obtain F waves at rest and post-exercise. The following variables were estimated and the obtained pre- and post-exercise data were compared: F persistence, F wave latency, amplitude, duration and F chronodispersion. For each nerve studied, the minimum, average and maximum values were calculated. Conventional electrophysiological data were also collected pre- and post-exercise and the data obtained were also compared. Twenty-five healthy age-, gender- and height-matched individuals served as controls. RESULTS: No evidence of conventional nerve conduction abnormalities was recorded either pre- or post-exercise in the group of patients. As regards the peroneal nerve, the significantly reduced F wave persistence (P = 0.007) and maximum F wave amplitude post- as opposed to pre-exercise (P = 0.05)- were the main findings to emerge. The average (P = 0.017) and the minimum duration (P = 0.005) of tibial F waves were also significantly increased post- compared with pre-exercise. Insignificant differences were observed between pre- and post-exercise neurophysiological and F wave values in the group of controls. CONCLUSION: Given the observed absence of conventional neurophysiological abnormalities, the detection of dynamic F wave changes supports the view of an increased diagnostic sensitivity of this method in patients with mild PAD.

Peripheral large nerve fibre function in patients with chronic plaque psoriasis.

Accumulating evidence suggests the involvement of neurogenic inflammation in the pathogenesis of psoriasis. Moreover, the concomitant occurrence of peripheral neuropathy has been reported in several psoriatic patients. Thus, the aim of the present study was to answer the question whether an impairment of peripheral large nerve fibre function may exist in psoriasis. Thirty-two patients with severe and generalized chronic plaque psoriasis and 32 sex- and age-matched healthy controls were evaluated by detailed clinical neurological and standard neurophysiological examination. The latter included motor nerve conduction study of one nerve in the upper and one in the lower extremities and sensory nerve conduction study of one nerve in the upper and two in the lower extremities. Neurological examination failed to demonstrate any clinical evidence of large fibre neuropathy. Furthermore, all values of the examined neurophysiological parameters were within normal limits; comparisons of the corresponding mean values in the patient and the control group showed no statistically significant differences. These findings demonstrate no measurable abnormalities of the peripheral large nerve fibres in psoriatic patients and therefore an association of psoriasis with peripheral large fibre neuropathy cannot be suggested.

Efficacy of oxcarbazepine for prophylaxis against cumulative oxaliplatin-induced neuropathy.

We conducted a randomized, open-label, controlled trial to assess the efficacy of oxcarbazepine for prophylaxis against oxaliplatin-induced peripheral neuropathy (OxIN). Thirty-two patients with colon cancer received 12 courses of the FOLFOX-4 regimen and were randomly assigned to receive oxcarbazepine (600 mg BID) or chemotherapy without oxcarbazepine. The incidence of OxIN was strikingly decreased in patients receiving oxcarbazepine (31.2% vs 75%). Oxcarbazepine may prevent OxIN symptoms. Further larger placebo-controlled trials are warranted to confirm our results.

Factors associated with poor compliance of patients with epilepsy driving restrictions.

The authors sought to identify factors associated with poor compliance with driving restrictions due to a diagnosis of epilepsy. They compared the demographic and clinical characteristics of 60 patients with epilepsy who, despite the authors' recommendation, continued to drive, with those of 60 age- and sex-matched epileptic patients who refrained from driving. The results showed that patients with epilepsy do not comply with driving restrictions, mainly for employment-related reasons.

Lunar phases and seizure occurrence: just an ancient legend?

The authors retrospectively reviewed all neurologic records of an emergency unit from 1999 to 2003 to identify a potential association between lunar phases and seizure occurrence. Overall 859 patients admitted for seizure occurrence were divided into the four quarters of the synodic month according to moon phases. A significant clustering of seizures around the full moon period was observed, supporting the ancient belief of periodic increased seizure frequency during full-moon days.

The significance of intact sympathetic skin responses in carpal tunnel syndrome.

The current study aimed to investigate the impact of carpal tunnel syndrome (CTS) on sympathetic skin response (SSR) recorded from the median and ulnar territory. Thirty patients were studied and idiopathic CTS was documented in a total of 46 hands. These were classified, according to electrophysiological criteria, into two groups; a group of 31 hands with severe CTS and a group of 15 hands with mild/moderate CTS, and were compared with a group of 30 hands of age-matched controls. SSR was recorded simultaneously from the median and ulnar side of the palm following electrical stimulation at the wrist, in a mid-point between median and ulnar nerve. Latency, amplitude, habituation and the median-to-ulnar ratio were estimated. In all controls clear recordings of SSR were obtained. In the patient groups, absence of SSR was never observed either in mild/moderate or in the severe CTS hands. The mean SSR latency and amplitude values recorded from both the median and ulnar nerves did not significantly differ between mild/moderate or severe CTS hands and controls. Likewise, the median-to-ulnar ratio and habituation of SSR latencies and amplitudes did not significantly differ between groups. SSR does not seem to be a sensitive method for evidence of autonomic involvement in CTS, even in patients manifesting sudomotor or other autonomic symptoms. In the present setting, SSR appeared to be independent of somatic afferent function and the corresponding sensory action potentials.

Headache characteristics and brain metastases prediction in cancer patients.

The aim of this study was to evaluate the headache and other neurological symptoms and signs as guide predictors for the occurrence of brain metastases in cancer patients. We prospectively studied 54 cancer patients with newly appeared headache or with a change in the pattern of an existing headache during the recent months. All patients completed a questionnaire regarding headache's clinical characteristics and existence of accompanying symptoms. They also underwent a detailed neurological, ophthalmologic examination and brain neuroimaging investigation. Brain metastases were diagnosed in 29 patients. Univariate regression analysis showed an association between occurrence of brain metastases and nine clinical symptoms or signs. Multivariate regression analyses emerged only four of them as significant independent predictors. These were: bilateral frontal-temporal headache, more pronounced on the side of metastasis in cases of single metastases, with duration > or =8 weeks, pulsating quality and moderate to severe intensity (OR: 11.9; 95% CI. 2.52-56.1), emesis (OR: 10.2; 95% CI. 2.1-55.8), gait instability (OR: 7.4; 95% CI. 1.75-33.9) and extensor plantar response (OR: 12.1; 95% CI. 2.2-120.7). In conclusion, all cancer patients who manifest the above independent clinical predictors should be highly suspected for appearance of brain metastases and therefore should be thoroughly investigated.

The impact of paclitaxel or cisplatin-based chemotherapy on sympathetic skin response: a prospective study.

The current study aimed to assess the viability of sympathetic sudomotor fibers in cancer patients treated with cisplatin or paclitaxel-based chemotherapy and to ascertain whether this method could contribute to the diagnostic sensitivity of conventional techniques. Sympathetic skin response (SSR) from the hand and sole of 23 cancer patients (nine females and 14 males, mean age 62.4 +/- 10.5 years) was recorded unilaterally before and after chemotherapy with six courses of cumulative cisplatin or paclitaxel containing regimens. Clinical and electrophysiological data were also collected and correlated with the SSR results. Twenty-three healthy subjects served as controls. SSR abnormalities were only present in patients with evidence of peripheral neuropathy assessed by conventional nerve conduction techniques. Three patients had absent SSR in the upper limb whilst six patients had absent SSR both in the upper and lower limbs. In the upper limb, the mean SSR latency was not significantly altered through time (P = 0.086). In the lower limb the mean delay from baseline to follow-up was significantly changed (P = 0.029). In patients, the mean SSR latency was significantly prolonged compared with controls in both upper limb (P = 0.001) and lower limb (P = 0.000). SSR abnormalities were strongly related to sensory conduction abnormalities as detected by conventional techniques (r = 0.39, P = 0.004). Our results showed that SSR does not seem to add to the diagnostic sensitivity of conventional techniques in chemotherapy-induced neuropathy. However, its role in the disclosure of small fibers neuropathy abnormalities is worth considering. Further studies are warranted to address this important issue.