A Delphi consensus statement of the Neuropathic Pain Special Interest Group of the Italian Neurological Society on pharmacoresistant neuropathic pain.

To improve patient care and help clinical research, the Neuropathic Pain Special Interest Group of the Italian Neurological Society appointed a task force to elaborate a consensus statement on pharmacoresistant neuropathic pain. The task force included 19 experts in neuropathic pain. These experts participated in a Delphi survey consisting of three consecutive rounds of questions and a face-to-face meeting, designed to achieve a consensus definition of pharmacoresistant neuropathic pain. In the three rounds of questions, the participants identified and described the main distinguishing features of pharmacoresistance. In the face-to-face meeting the participants discussed the clinical features determining pharmacoresistance. They finally agreed that neuropathic pain is pharmacoresistant when "the patient does not reach the 50% reduction of pain or an improvement of at least 2 points in the Patient Global Impression of Change, having used all drug classes indicated as first, second, or third line in the most recent and widely agreed international guidelines, for at least 1 month after titration to the highest tolerable dose." Our consensus statement might be useful for identifying eligible patients for invasive treatments, and selecting patients in pharmacological trials, thus improving patient care and helping clinical research.

Pharmacological differences and clinical implications of various botulinum toxin preparations: a critical appraisal.

Three different type A botulinum neurotoxins (BoNTAs) - onabotulinumtoxinA, abobotulinumtoxinA and incobotulinumtoxinA) - are currently marketed in Europe to treat several conditions. Differences between BoNTA preparations, which depend on their specific biotypes and manufacturing processes, lead to clinically relevant pharmacotherapeutic dissimilarities. All three available products are separately recognized and reviewed in American Academy of Neurology guidelines. The neurotoxin load/100U is likewise different among the different BoNTAs, with the result that the specific potency of the 150kD BoNTA neurotoxin is calculated as 137 units/ng for onabotulinumtoxinA, 154 units/ng for abobotulinumtoxinA, and 227 units/ng for incobotulinumtoxinA. It is important for clinicians to have all three BoNTAs available in order to choose the most suitable preparation for the specific indication in the single patient. Commercially available BoNTAs must be recognized as different from one another, and therefore as non-interchangeable. The essential experience of the clinician is of the utmost importance in choosing the most appropriate treatment.

Intraoperative monitoring of sensory part of the trigeminal nerve using blink reflex during microvascular decompression for trigeminal neuralgia.

Intraoperative monitoring during cerebellopontine angle surgery is widely accepted. While techniques which monitor cranial motor nerves are commonly used, monitoring the sensory afferents has been challenging. Considering the reflex arc, blink reflex (BR) might be useful in monitoring the sensory part of the trigeminal nerve, the brainstem connections and the facial nerve. We describe the case of a patient who developed hemifacial hypoesthesia after microvascular decompression surgery for trigeminal neuralgia. Intraoperative BR showed a severe loss of R1 amplitude. BR might be a useful intraoperative technique to monitor the sensory part of the trigeminal nerve.

Peripheral neuropathy in 30 duodopa patients with vitamins B supplementation.

OBJECTIVES: Peripheral neuropathy (PN) is a significant concern and potential cause of withdrawal in patients with Parkinson's disease (PD) treated with Levodopa/Carbidopa Intestinal Gel (LCIG) infusion. Vitamin B deficiency and/or hyperhomocysteinemia levodopa-related are considered possible causative factors. In this study, we evaluated PN incidence in LCIG-PD patients treated since the beginning of infusion with vitamins B supplementation. MATERIALS & METHODS: In this prospective open-label pilot study, 30 consecutive patients with PD on LCIG infusion were evaluated with clinical, neurophysiological, and biochemical assessments for a mean follow-up of 42.4 months (range 24-72). All evaluations were repeated every 6 months. RESULTS: At baseline, 21 of 30 presented no signs or symptoms of PN, and 9 of 30 had pre-existing chronic PN. In whole population, a progressive worsening in nerve conduction studies of sural sensory and peroneal motor nerves was observed during the long-term follow-up. 4 of 21 patients, with normal clinical, electrophysiological assessment at baseline, developed distal symmetrical axonal polyneuropathy that remained asymptomatic during the long-term follow-up. Patients with pre-existing PN (9 of 30) showed a mild worsening of electrophysiological features during the period of observation. In none PN was cause of discontinuation of LCIG therapy. No incident cases of acute-subacute PN were documented. No correlation was found with age, sex, Levodopa dosage, duration of levodopa exposure, and homocysteine plasma levels. CONCLUSION: In this consecutive series of 30 patients with PD on LCIG infusion, with early and continuous vitamins B integration, we observed a low rate (19%) of new onset peripheral polyneuropathy that remained stable after long-term follow-up. Larger studies, controlled, with blinded evaluation, are needed to confirm these findings.

How to diagnose neuropathic pain? The contribution from clinical examination, pain questionnaires and diagnostic tests.

Patients with peripheral and central nervous system diseases may suffer from different types of pain, namely nociceptive, neuropathic and mixed pain. Although in some cases, the distinction between these types of pain is clinically evident, yet in some patients an accurate differential diagnosis requires dedicated clinical examination, screening questionnaires and diagnostic techniques some of which are available only in specialized pain centres. This review briefly addresses the currently agreed definitions of the different types of pain and shows how clinical examination, pain questionnaires and diagnostic tests can help the clinicians in identifying neuropathic pain.

Space-time distribution of the ALS incident cases by onset type in the Health District of Ferrara, Italy.

OBJECTIVES: An ecological study in the resident population of the Health District (HD) of Ferrara, Italy, has been carried out to establish the distribution in space and time of the amyotrophic lateral sclerosis (ALS) incident cases according to the disease onset type and gender in the period 1964-2009. MATERIAL AND METHODS: The hypothesis of a uniform distribution was assumed. RESULTS: The incident cases of spinal onset ALS and bulbar onset ALS were evenly distributed in space and time in both men and women. The spinal onset ALS incident cases distribution according to gender was significantly different from the expected in the extra-urban population (20 observed cases in men 95% Poisson confidence interval 12.22-30.89, expected cases in men 12.19; six observed cases in women 95% Poisson confidence interval 2.20-13.06, expected cases in women 13.81), whereas no difference was found in the urban population. The spinal onset ALS incidence was higher in men than in women in the extra-urban population (difference between the rates = 1.53, 95% CI associated with the difference 0.52-2.54), whereas no difference between sexes was found in the urban population. CONCLUSIONS: The uneven distribution according to gender of the spinal onset ALS incident cases only in the extra-urban population suggests the involvement of a gender related environmental risk factor associated with the extra-urban environment. Despite some limits of the spatial analysis in the study of rare diseases, the results appear consistent with the literature data.

Emerging issues on selection criteria of levodopa carbidopa infusion therapy: considerations on outcome of 28 consecutive patients.

Many studies confirmed the efficacy and safety of continuous infusion of intrajejunal levodopa/carbidopa gel (CIILG) for advanced Parkinson's disease (PD). Although this treatment is widely used, definite inclusion/exclusion criteria do not exist. In this prospective open-label study, we evaluated the long-term outcome in 28 consecutive patients and sought to detect any predictive factor to identify the best candidates for CIILG therapy. The assessment was carried out routinely at baseline, after 6 months and every year with UPDRS III-IV, FOG Questionnaire, non-motor symptoms scale, PD questionnaire (PDQ-8), cognitive and psychiatric status evaluation (MMSE, FAB, NPI) and caregiver's quality of life. 17/28 patients reached the 24-month follow-up. A statistically significant beneficial effect was shown on motor complications in short- and long-term follow-up, also on axial symptoms like gait disturbances. A concomitant improvement in PDQ8 score was observed, with a parallel mild amelioration, but not significant, on Caregivers QoL. When classified according to their outcome on QoL, the only predictive positive factor was less severe at Neuropsychiatric Inventory (NPI) score at baseline. Considering the improvement in motor scores (duration of "off" period), the more advanced age was associated with a poorer outcome. Our results confirmed a sustained efficacy and safety in long-term follow-up and suggest that younger age at operation and absence or mild presence of psychiatric/behavioural symptoms could be considered valid predicting factors in selecting the best candidates for this efficacious therapy.

Spinal anesthesia and minimal invasive laminotomy for paddle electrode placement in spinal cord stimulation: technical report and clinical results at long-term followup.

OBJECT: We arranged a mini-invasive surgical approach for implantation of paddle electrodes for SCS under spinal anesthesia obtaining the best paddle electrode placement and minimizing patients' discomfort. We describe our technique supported by neurophysiological intraoperative monitoring and clinical results. METHODS: 16 patients, affected by neuropathic pain underwent the implantation of paddle electrodes for spinal cord stimulation in lateral decubitus under spinal anesthesia. The paddle was introduced after flavectomy and each patient confirmed the correct distribution of paresthesias induced by intraoperative test stimulation. VAS and patients' satisfaction rate were recorded during the followup and compared to preoperative values. RESULTS: No patients reported discomfort during the procedure. In all cases, paresthesias coverage of the total painful region was achieved, allowing the best final electrode positioning. At the last followup (mean 36.7 months), 87.5% of the implanted patients had a good rate of satisfaction with a mean VAS score improvement of 70.5%. CONCLUSIONS: Spinal cord stimulation under spinal anesthesia allows an optimal positioning of the paddle electrodes without any discomfort for patients or neurosurgeons. The best intraoperative positioning allows a better postoperative control of pain, avoiding the risk of blind placements of the paddle or further surgery for their replacement.

Awake surgery in low-grade gliomas harboring eloquent areas: 3-year mean follow-up.

Low-grade gliomas are slow-growing tumors invading eloquent areas and white matter pathways. For many decades these tumors were considered inoperable because of their high tropism for eloquent areas. However, the young age of the patients and the inescapable anaplastic transformation have recently suggested more aggressive treatments. We analyzed the neurological and neuro-oncological outcome of 12 patients who underwent surgery fully awake for the resection of LGG, harboring eloquent areas. 10 right- and 2 left-handed patients underwent pre-operative assessment: Karnofsky Performance Status, Edinburgh Handedness Inventory Score; neuropsychological and neurophysiological evaluations, according to the tumor location. During surgery we performed: sensory-motor-evoked potentials, continuous electro-corticography and bipolar/monopolar cortico-subcortical mapping during neuropsychological tests. The resection rate was calculated with neuro-imaging elaboration software. No permanent post-operative deficits were reported; 2 patients improved after surgery. No impairment of cognitive functions was reported. The KPS improved in 8 patients and was steady in the others. The mean resection rate was 78.3%. The resection allowed the control of pre-operative seizures without increasing the drug intake. Awake surgery allowed a good resection rate despite the eloquent location of the tumors, without post-operative deficit. The neuropsychological outcome was unchanged after surgery. The resection seems to improve seizure control. All the patients came back to normal life and work. In conclusion, awake surgery is reliable and feasible in removal of LGG, even if invading the main eloquent areas and networks. All the patients experienced a normal life after surgery, without permanent deficits.

Effect of slow rTMS of motor cortex on the excitability of the blink reflex: a study in healthy humans.

OBJECTIVE: To evaluate the after-effects of low frequency, sub-threshold repetitive Transcranial Magnetic Stimulation (rTMS) of primary motor cortex, on the excitability of Blink Reflex (BR) in healthy subjects. METHODS: The BR recovery cycle was carried out in 10 healthy volunteers in basal conditions, immediately after rTMS (30s), 15 and 60min later. A paired electric supraorbital stimulus paradigm with inter-stimulus intervals (ISI) of 100-600-1000-1500ms was used. The "real" rTMS consisted of a 200 stimuli long train delivered at 1Hz and intensity 80% of rest Motor Threshold of the FDI muscle, using a focal coil applied over the primary motor cortex region. The basal BR recovery cycle was also compared with that obtained after a "sham" rTMS. RESULTS: The recovery of the R2 component of the BR was significantly suppressed 30s after rTMS. This effect was also observed at 15min, though of lower magnitude and only at long ISIs (1000-1500ms). No significant effect on R2 recovery was observed 60min after real rTMS as well as after sham rTMS. CONCLUSIONS: rTMS of motor cortex modulates the excitability of BR through its action on cortical excitability and on the cortical facilitatory drive to the brainstem reflex pathways. SIGNIFICANCE: Slow (1Hz), sub-threshold rTMS of motor cortex determines a long-lasting reduction of excitability of BR.

Metabolic findings on 3T 1H-MR spectroscopy in peritumoral brain edema.

BACKGROUND AND PURPOSE: Little is known about the metabolic properties of brain edema associated with tumors. This work was conducted on the basis of the assumption that, in the presence of intra-axial and extra-axial brain tumors, the white matter involved by the edema is a site of metabolic change that involves the structure of the myelin sheath. MATERIALS AND METHODS: Thirteen patients comprised our cohort affected by intra-axial and extra-axial cerebral tumors with a peritumoral T2-weighted MR signal hyperintensity as a result of edema, where MR spectroscopy showed no increase in choline-containing compounds. Measurements on proton MR spectroscopy (1H-MR spectroscopy) were performed with a 3T whole-body scanner with use of a point-resolved spectroscopy sequence for localization (TR, 2000 ms; TE, 35 ms), and the metabolites were quantified with the SAGE method. Peak intensities of the main metabolites were expressed as ratios of one another and were compared with values obtained in the white matter of the left frontal region in a control group of 16 healthy volunteers. RESULTS: Choline-to-creatine (Cho/Cr) and myo-inositol-to-creatine (mIns/Cr) signal intensity ratios were normal in all patients. N-acetylaspartate-to-creatine (NAA/Cr) and N-acetylaspartate-to-choline (NAA/Cho) ratios decreased in 4 patients. Glutamate plus glutamine-to-creatine (Glx/Cr) was increased in 10 patients. A resonance peak at 3.44 ppm, strongly suggesting the presence of glucose, was detected in all but 1 patient. Lactate was detected in 12 patients and lipids in 5. Moreover, the resonances that pertained to the aliphatic amino acids valine, leucine, and isoleucine were present in 12 patients. CONCLUSIONS: Our findings on MR spectroscopy confirmed the hypothesis that in the edema surrounding brain tumors, an energy-linked metabolic alteration was associated with injury to the myelin sheath.

The auxin-like activity of humic substances is related to membrane interactions in carrot cell cultures.

A detailed characterization of two humic fractions was performed: One with low relative molecular mass (LMr<3,500 Da) and one with high relative molecular mass (HMr>3,500 Da). Distinct (1)H NMR spectroscopic patterns were observed for the two fractions. HMr showed an aromatic proton region, an intense and broad region (3.0-5.0 ppm) attributed to sugar-like and polyether components, and an intense doublet at 1.33 ppm (identified as protons of the beta-CH(3) in lactate). In contrast, LMr did not show resonances due to aromatic protons and was characterized by a broad unresolved region, assigned to sugar-like components. The (13)C NMR spectra showed that the LMr humic fraction was richer in carboxylic and aliphatic C groups compared to HMr fraction. These substances were fluorescein-labeled [fluorescein isothiocyanate (FITC)], and their interaction with carrot cells in culture was monitored for 10 d, and compared to FITC-indole-3-acetic acid (IAA) to clarify their mechanisms of biological activity. After different incubation times, fluorescein staining of carrot cells and decrease of fluorescein concentration in the culture medium were evaluated. Fluorescent membrane staining was only present in IAA and the LMr humic fraction treated cell cultures. A consequential decrease of fluorescein concentration in the culture media was also observed. Pretreatment of carrot cells with unconjugated IAA or LMr humic fraction markedly reduced fluorescein staining of both FITC-IAA and FITC-LMr humic fraction. Blocking tests gave indirect evidence of possible binding of the LMr humic fraction to IAA cell membrane receptors. These results indicate that the two humic fractions behave differently. Only LMr humic fraction, like IAA, interacts with cellular membranes in carrot cell cultures.

Superoxide dismutase in gastric adenocarcinoma: is it a clinical biomarker in the development of cancer?

Gastric cancer is the second most common cancer worldwide. The involvement of reactive oxygen species (ROS) in the pathogenesis of gastric malignancies is well known. Many human tumours have shown significant changes in the activity and expression of superoxide dismutase (SOD), which might be correlated with clinical-pathological parameters for the prognosis of human carcinoma. The aim of this study is the detection of MnSOD and CuZnSOD activity and their expression in gastric adenocarcinoma and healthy tissues. Gastric samples (adenocarcinoma and healthy tissues) harvested during endoscopy or resected during surgery were used to determine MnSOD and CuZnSOD activity and expression by spectrophotometric and Western blotting assays. The total SOD activity was significantly higher (p<0.05) in healthy mucosa with respect to gastric adenocarcinomas. No differences were found in MnSOD activity and, on the contrary, CuZnSOD activity was significantly lower (p<0.001) in cancer samples with respect to normal mucosa. The rate of MnSOD/CuZnSOD activity in adenocarcinoma was over ninefold higher than that registered in healthy tissues (p<0.05). Moreover, in adenocarcinoma MnSOD activity represented the 83% of total SOD with respect to healthy tissues where the ratio was 52% (p<0.001). On the contrary, in cancer tissues, CuZnSOD activity accounted for only 17% of the total SOD (p<0.001 if compared with the values recorded in normal mucosa). After immunoblotting, MnSOD was more expressed in adenocarcinoma with respect to normal mucosa (p<0.001), while CuZnSOD was similarly expressed in adenocarcinoma and healthy tissues. The SOD activity assay might provide a specific and sensitive method of analysis that allows the differentiation of healthy tissue from tumour tissue. The MnSOD to CuZnSOD activity ratio, and the ratio between these two isoforms and total SOD, presented in this preliminary study might be considered in the identification of cancerous from healthy control tissue.

Ex vivo HR-MAS Magnetic Resonance Spectroscopy of human gastric adenocarcinomas: a comparison with healthy gastric mucosa.

The present study reports the characteristics of the biochemical profile of human gastric adenocarcinoma in comparison with that of healthy gastric mucosa, using ex vivo HR-MAS Magnetic Resonance Spectroscopy. Healthy human mucosa is mainly characterized by the presence of small metabolites (more than 50 identified) and macromolecules, whereas the adenocarcinoma spectra are dominated by the presence of signals due to triglycerides, whose content on the contrary is very low in healthy gastric mucosa. The use of spin-echo experiments enable us to detect some metabolites in the unhealthy tissues and to determine their variation with respect to the healthy ones. We have observed that the Cho:ChoCC ratio changes from 20:80 in the healthy tissues to 80:20 in the neoplastic gastric mucosa.

Clinical use of non-A botulinum toxins: botulinum toxin type C and botulinum toxin type F.

Botulinum neurotoxin (BoNT) serotype A is commonly used in the treatment of focal dystonia, but some patients are primarily or become secondarily resistant to it. Consequently, other serotypes have to be used when immuno-resistance is proven. In the literature, patients with focal dystonia have been treated with BoNT serotype F with clinical benefit but with short lasting effects. Recently, BoNT serotype C has been used with positive clinical outcome. An update on the clinical use of BoNT serotype F and BoNT serotype C is provided.

A comparison between in vivo and ex vivo HR-MAS 1H MR spectra of a pediatric posterior fossa lesion.

The present case report was aimed at identifying the molecular profile characteristic of a primitive neuro-ectodermal tumor (PNET) in a 3-year-old child affected by a lesion localized in the cerebellar region. The histological diagnosis was medulloblastoma. In vivo single voxel 1H magnetic resonance spectroscopy (MRS) shows high specificity in detecting the main metabolic alterations in the primitive cerebellar lesion; a very high amount of the choline-containing compounds and very low level of creatine derivatives and N-acetylaspartate. Ex vivo high resolution magic angle spinning (HR-MAS) 1H magnetic resonance spectroscopy, performed at 9.4 Tesla on the neoplastic specimen collected during surgery, allows for the unambiguous identification of several metabolites giving a more in-depth evaluation of the metabolic pattern of the lesion. The ex vivo HR-MAS MR spectra show that the spectral detail is much higher than that obtained in vivo and that, for example, myo-inositol, taurine and phosphorylethanolamine contribute to the in vivo signal at 3.2 ppm, usually attributed to choline-containing compounds. In addition, the spectroscopic data appear to correlate with some morphological features of the medulloblastoma. Consequently, the present study shows that ex vivo HR-MAS 1H MRS is able to strongly improve the clinical possibility of in vivo MRS and can be used in conjunction with in vivo spectroscopy for clinical purposes.

Molecular characterization of human gastric mucosa by HR-MAS magnetic resonance spectroscopy.

The present study was aimed at identifying the molecular profile characteristic of the healthy human gastric mucosa. Ex vivo HR-MAS magnetic resonance spectroscopy performed at 9.4 Tesla (400.13 MHz for (1)H) on gastric specimens collected during endoscopy, permits the identification of more than forty species giving a detailed picture of the biochemical pattern of the gastric tissues. These preliminary data will be used for a comparison with gastric preneoplastic and neoplastic situations. Moreover, the full knowledge of the biochemical pattern of the healthy gastric tissues is the necessary presupposition for the application of magnetic resonance spectroscopy directly in vivo.

Phosphatidylcholine and cholesteryl esters identify the infiltrating behaviour of a clear cell renal carcinoma: 1H, 13C and 31P MRS evidence.

This study presents a multinuclear (1H, 13C and 31P) magnetic resonance spectroscopy characterization of the total lipid fraction extracted from different regions of a human kidney affected by a clear cell renal carcinoma. It was thus possible to demonstrate that cholesteryl esters and phosphatidylcholine are markers of the tumor infiltration, histologically confirmed, in the kidney medulla. The tumor tissue contains twice the amount of phosphatidylcholine compared to normal cortex. The results appear relevant in light of new clinical applications based on the biochemical composition of human tissues.

Magnetic resonance spectroscopy and chromatographic methods identify altered lipid composition in human renal neoplasms.

We report on the characterization of the lipid obtained from cortical and medullary normal human kidney tissue, benign renal neoplasms (oncocytoma) and 2 different types of malignant renal neoplasms (chromophobic cell carcinoma and clear cell carcinoma). The total lipid fractions were analyzed by 13C magnetic resonance spectroscopy and thin-layer chromatography, whereas the composition of the total fatty acids and the content of total cholesterol were determined by gas chromatography. alpha-Tocopherol was detected and quantified by high-performance liquid chromatography. The spectroscopic and chromatographic analysis revealed significant differences in the renal tissues examined. It was confirmed that cholesteryl esters (mainly oleate) are typical of clear cell renal carcinomas. Their potential role as prognostic and diagnostic factors is discussed, with particular emphasis on its capability to indicate the tumor diffusion in healthy renal parenchyma. alpha-Tocopherol is prevalent in clear cell carcinoma and it is present in nearly the same low amounts in cortex, medulla and chromophobic cell renal carcinoma. Q10 coenzyme and dolichols were detected by thin-layer chromatography and they are present in significant amounts in the cortex and the benign oncocytoma. Great variations were found in the distribution of saturated and unsaturated fatty acids, especially in the docosapentaenoic, docosahexaenoic and arachidonic acids and the corresponding omega-6/omega-3 fatty acids ratio.

Explosive-aggressive behavior related to bilateral subthalamic stimulation.

We describe a patient with Parkinson's Disease who underwent bilateral subthalamic nucleus deep brain stimulation and later presented with episodes of aggressive behavior disorder with disturbed impulse control and an inability to control anger likely related to the deep brain stimulation "switch-on stimulation". We hypothesize that increasing voltage intensity could influence neighboring passing fibers coming from basal limbic system that are involved in the regulation of affect and emotional behavior. We suggest investigating these neuropsychological disturbances considering their influence on quality of life after surgery.