Comparison between deep brain stimulation and magnetic resonance-guided focused ultrasound in the treatment of essential tremor: a systematic review and pooled analysis of functional outcomes.

The current gold standard surgical treatment for medication-resistant essential tremor (ET) is deep brain stimulation (DBS). However, recent advances in technologies have led to the development of incisionless techniques, such as magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy. The authors perform a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement to compare unilateral MRgFUS thalamotomy to unilateral and bilateral DBS in the treatment of ET in terms of tremor severity and quality of life improvement. PubMed, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials and SCOPUS databases were searched. 45 eligible articles, published between 1990 and 2019, were retrieved. 1202 patients were treated with DBS and 477 were treated with MRgFUS thalamotomy. Postoperative tremor improvement was greater following DBS than MRgFUS thalamotomy (p<0.001). A subgroup analysis was carried out stratifying by treatment laterality: bilateral DBS was significantly superior to both MRgFUS and unilateral DBS (p<0.001), but no significant difference was recorded between MRgFUS and unilateral DBS (p<0.198). Postoperative quality of life improvement was significantly greater following MRgFUS thalamotomy than DBS (p<0.001). Complications were differently distributed among the two groups (p<0.001). Persistent complications were significantly more common in the MRgFUS group (p=0.042). While bilateral DBS proves superior to unilateral MRgFUS thalamotomy in the treatment of ET, a subgroup analysis suggests that treatment laterality is the most significant determinant of tremor improvement, thus highlighting the importance of future investigations on bilateral staged MRgFUS thalamotomy.

Dissociable Contributions of Precuneus and Cerebellum to Subjective and Objective Neuropathy in HIV.

Neuropathy, typically diagnosed by the presence of either symptoms or signs of peripheral nerve dysfunction, remains a frequently reported complication in the antiretroviral (ART)-treated HIV population. This study was conducted in 109 healthy controls and 57 HIV-infected individuals to investigate CNS regions associated with neuropathy. An index of objective neuropathy was computed based on 4 measures: deep tendon ankle reflex, vibration sense (great toes), position sense (great toes), and 2-point discrimination (feet). Subjective neuropathy (self-report of pain, aching, or burning; pins and needles; or numbness in legs or feet) was also evaluated. Structural MRI data were available for 126/166 cases. The HIV relative to the healthy control group was impaired on all 4 signs of neuropathy. Within the HIV group, an objective neuropathy index of 1 (bilateral impairment on 1 measure) or 2 (bilateral impairment on at least 2/4 measures) was associated with older age and a smaller volume of the cerebellar vermis. Moderate to severe symptoms of neuropathy were associated with more depressive symptoms, reduced quality of life, and a smaller volume of the parietal precuneus. This study is consistent with the recent contention that ART-treated HIV-related neuropathy has a CNS component. Distinguishing subjective symptoms from objective signs of neuropathy allowed for a dissociation between the precuneus, a brain region involved in conscious information processing and the vermis, involved in fine tuning of limb movements. Graphical Abstract In HIV patients, objective signs of neuropathy correlated with smaller cerebellar vermis (red) volumes whereas subjective symptoms of neuropathy were associated with smaller precuneus (blue) volumes.

Comparison of sustained-release and rapid-release ß-alanine formulations on changes in skeletal muscle carnosine and histidine content and isometric performance following a muscle-damaging protocol.

ß-alanine supplementation increases muscle carnosine content and improves anaerobic exercise performance by enhancing intracellular buffering capacity. ß-alanine ingestion in its traditional rapid-release formulation (RR) is associated with the symptoms of paresthesia. A sustained-release formulation (SR) of ß-alanine has been shown to circumvent paresthesia and extend the period of supply to muscle for carnosine synthesis. The purpose of this investigation was to compare 28 days of SR and RR formulations of ß-alanine (6 g day-1) on changes in carnosine content of the vastus lateralis and muscle fatigue. Thirty-nine recreationally active men and women were assigned to one of the three groups: SR, RR, or placebo (PLA). Participants supplementing with SR and RR formulations increased muscle carnosine content by 50.1% (3.87 mmol kg-1ww) and 37.9% (2.62 mmol kg-1ww), respectively. The change in muscle carnosine content in participants consuming SR was significantly different (p = 0.010) from those consuming PLA, but no significant difference was noted between RR and PLA (p = 0.077). Although participants ingesting SR experienced a 16.4% greater increase in muscle carnosine than RR, fatigue during maximal voluntary isometric contractions was significantly attenuated in both SR and RR compared to PLA (p = 0.002 and 0.024, respectively). Symptoms of paresthesia were significantly more frequent in RR compared to SR, the latter of which did not differ from PLA. Results of this study demonstrated that only participants consuming the SR formulation experienced a significant increase in muscle carnosine. Differences in the muscle carnosine response between these formulations may have practical significance for athletic populations in which small changes may have important implications on performance.

Is mannitol the treatment of choice for patients with ciguatera fish poisoning?

CONTEXT: Ciguatera fish poisoning arises primarily from consumption of carnivorous reef fish caught in tropical and sub-tropical waters. Ciguatoxins, a class of tasteless, heat-stable, polycyclic toxins produced by dinoflagellates, accumulate through the food chain and concentrate in various carnivorous fish, such as groupers, barracudas, wrasses, amberjack, kingfishes, and eels. Characteristics of ciguatera fish poisoning include early nausea, vomiting, and diarrhea in the first one to two days post ingestion, followed by the appearance of sensory disturbances. The classic dysaesthesia is cold allodynia, often described as reversal of hot and cold sensation, but a more accurate description is burning pain on exposure to cold. OBJECTIVE: To discuss and appraise the evidence regarding the use of mannitol or other drugs in treating ciguatera framed in the historical context of the last four decades. METHODS: We searched PubMed and Embase for all years from 1966 to March 31, 2017 with search terms "ciguatera", "mannitol", and "treatment". These searches identified 85 articles, of which 36 were relevant to the review question. We searched Google Scholar to supplement the primary search and reviewed the references of articles for sources overlooked in the original searches. These secondary searches identified another 23 references. We excluded six clinical reports (two case series and four case reports) which did not clearly describe ciguatera or which lacked information on treatment or outcome. Fifty-three clinical articles remained for review. We searched PubMed using "ciguatera" AND "treatment" NOT "mannitol" to better identify reports describing other treatments. The search identified 128 articles, of which nine described specific pharmacological treatments and their outcomes. We combined our findings into a consensus review of the evidence both for and against the use of mannitol or other medications for ciguatera fish poisoning. Early human evidence of effectiveness of mannitol: A 1988 report described an unexpected discovery that intravenous mannitol could rapidly and effectively treat ciguatera fish poisoning. Several other uncontrolled case series and case reports appeared to support the use of mannitol. In 2002, a small randomized, controlled trial reported no significant difference between mannitol and normal saline. Subsequent case reports have cited this study as the reason for or to withhold mannitol. Thus, some controversy exists regarding whether mannitol is useful or not for treating ciguatera fish poisoning. Basic science and animal research on ciguatera and mannitol: In vitro experiments of isolated neurons demonstrate that ciguatoxins produce neuronal edema, open certain sodium channels, block potassium channels, cause uncontrolled and repetitive action potentials after a stimulus. Addition of mannitol decreases the edema and reduces the uncommanded action potentials. However, intraperitoneal injection of ciguatoxin in rats increases neuronal refractory period and slows nerve conduction velocity. Treatment with mannitol fails to correct these effects. Comparative trials of mannitol: Evidence supporting mannitol for ciguatera fish poisoning includes four uncontrolled case series, one prospective, unblinded comparative trial and several case reports. Evidence against mannitol consists of one RCT, which has a small sample size and several potential limitations. Empirical human experience with other treatments: Evidence regarding other treatments consists only of ten case reports and three overlapping case series that describe using amitriptyline, fluoxetine, duloxetine, gabapentin, pregabalin, or tocainide. For each of these, a long duration of treatment appears to be necessary to maintain symptomatic improvement. None of these treatments has been shown to be superior to mannitol. CONCLUSIONS: It is reasonable to consider using intravenous mannitol in cases of acute ciguatera fish poisoning. Medications used in other neuropathic syndromes appear to suppress the paresthesiae of persistent ciguatera cases. However, the human evidence is of low quality for all treatments.

Complaints of Upper Extremity Numbness and Tingling Relieved With Dry Needling of the Teres Minor and Infraspinatus: A Case Report.

Study Design Case report. Background Abnormal sensation, such as numbness or tingling, is traditionally thought to originate from neural compression. There is limited evidence to support reports of abnormal sensation arising from a trigger point. Case Description The patient was a 60-year-old woman with a primary complaint of right shoulder pain and secondary complaints of neck pain and right upper extremity numbness. Cervical spine neurological examination was unremarkable, and manual examination did not reproduce the patient's arm numbness or tingling symptoms. Compression of a trigger point in the infraspinatus and teres minor reproduced the patient's primary complaint of shoulder pain. The initial intervention included dry needling, which reproduced her upper extremity numbness. Subsequent treatment included manual therapy and exercise. Outcomes The patient was seen for a total of 3 visits, including the evaluation. Dry needling was utilized in 2 of her 3 visits. At discharge, she reported complete resolution of pain and altered sensation. Additionally, her scores on the Neck Disability Index, numeric pain-rating scale, and global rating of change exceeded the minimal clinically important difference. These outcomes were maintained at 2- and 12-month follow-up phone calls. Discussion This case report described the examination and use of dry needling in a case where the diagnosis was unclear. Clinicians may consider trigger point referral when examining patients with reports of abnormal sensation, especially when a more common cause cannot be identified. Level of Evidence Therapy, level 5. J Orthop Sports Phys Ther 2017;47(4):287-292. Epub 3 Mar 2017. doi:10.2519/jospt.2017.7055.

Evaluation of the toxicity of anticancer chemotherapy in patients with colon cancer.

BACKGROUND: Modern anticancer chemotherapy can cause numerous adverse effects in the organism, whose functioning has already been disrupted by the neoplastic process itself. OBJECTIVES: The aim of the study was to evaluate and compare the frequency and severity of the toxicity of FOLFOX-4 and CLF-1 anticancer therapy in patients with colon cancer, and to analyze certain factors that might have increased the toxicity of the chemotherapy. MATERIAL AND METHODS: The study involved 64 patients suffering from generalized colon cancer, including 48 patients treated according to the FOLFOX-4 regimen and 16 patients treated according to the CLF-1 regimen. The toxicity of each regimen was analyzed on the basis of a confidential questionnaire formulated by the authors and laboratory research according to the extended WHO toxicity criteria. RESULTS: The analysis of the symptoms of toxicity symptoms associated with the use of the FOLFOX-4 and CLF-1 therapeutic regimens revealed that the most common side effects included nausea and vomiting, despite ondansetron premedication, and neurotoxicity. Disruption of the functioning of the nervous system under the FOLFOX-4 regimen statistically significant exacerbation that increased with the number of chemotherapy cycles administered; this was more common and more severe in women. Paresthesia was also revealed to be a neurotoxic effect of the FOLFOX-4 regimen after termination of therapy. A statistically significant relationship was observed between the use of vitamin supplements and the incidence and severity of the toxicity of the FOLFOX-4 regimen. CONCLUSIONS: The findings of the current study regarding the toxicity of the FOLFOX-4 and CLF-1 therapy regimens should be taken into consideration when monitoring chemotherapy safety in colon cancer. The patients' tolerance of the administered medication and the side effects reported by patients should be constantly evaluated, which will help prevent these side effects, apply appropriate therapy and contribute to the improvement of the patients' quality of life. The functioning of the central nervous system should be carefully evaluated when planning the anticancer therapy, especially if repeated administration of neurotoxic drugs is necessary in cases of a recurrence of the disease. Chemotherapy should be thoroughly monitored for safety, especially in women over 65 years of age suffering from coexisting diseases. Colon cancer patients and their families should be informed of the risks of nutritional supplements before the start of the anticancer chemotherapy, and may need to dispense with their use.

Benefits of laser phototherapy on nerve repair.

Post-traumatic nerve repair represents a major challenge to health sciences. Although there have been great advances in the last few years, it is still necessary to find methods that can effectively enhance nerve regeneration. Laser therapy has been widely investigated as a potential method for nerve repair. Therefore, in this article, a review of the existing literature was undertaken with regard to the effects of low-power laser irradiation on the regeneration of traumatically/surgically injured nerves. The articles were selected using either electronic search engines or manual tracing of the references cited in key papers. In electronic searches, we used the key words as "paresthesia", "laser therapy", "low-power laser and nerve repair", and "laser therapy and nerve repair", considering case reports and clinical studies. According to the findings of the literature, laser therapy accelerates and improves the regeneration of the affected nerve tissues, but there are many conflicting results about laser therapy. This can be attributed to several variables such as wavelength, radiation dose, and type of radiation. All the early in vivo studies assessed in this research were effective in restoring sensitivity. Although these results indicate a potential benefit of the use of lasers on nerve repair, further double-blind controlled clinical trials should be conducted in order to standardize protocols for clinical application.

Barriers to investigator-initiated deep brain stimulation and device research.

The success of device-based research in the clinical neurosciences has overshadowed a critical and emerging problem in the biomedical research environment in the United States. Neuroprosthetic devices, such as deep brain stimulation (DBS), have been shown in humans to be promising technologies for scientific exploration of neural pathways and as powerful treatments. Large device companies have, over the past several decades, funded and developed major research programs. However, both the structure of clinical trial funding and the current regulation of device research threaten investigator-initiated efforts in neurologic disorders. The current atmosphere dissuades clinical investigators from pursuing formal and prospective research with novel devices or novel indications. We review our experience in conducting a federally funded, investigator-initiated, device-based clinical trial that utilized DBS for thalamic pain syndrome. We also explore barriers that clinical investigators face in conducting device-based clinical trials, particularly in early-stage studies or small disease populations. We discuss 5 specific areas for potential reform and integration: (1) alternative pathways for device approval; (2) eliminating right of reference requirements; (3) combining federal grant awards with regulatory approval; (4) consolidation of oversight for human subjects research; and (5) private insurance coverage for clinical trials. Careful reformulation of regulatory policy and funding mechanisms is critical for expanding investigator-initiated device research, which has great potential to benefit science, industry, and, most importantly, patients.

Anamnestic findings from patients with recurrent aphthous stomatitis.

Recurrent aphthous stomatitis (RAS) is a common oral disorder with a prevalence varying between 5% and 66%. RAS appears in three forms; minor, major and herpetiform. The aetiology is unknown.The aim of this study was to evaluate associations between specific anamnestic information and different types of recurrent aphthous stomatitis (RAS). A group of 177 patients (mean age = 42.8 years; SD = 14.3; range 17-79 years) participated. Data were collected from a structured interview, consisting of 22 questions. Information about i) health status and medication, ii) predisposing factors, iii) RAS experience, iv) previous treatment methods and v) brand of toothpaste was collected. Sixty-eight per cent of the patients were healthy and 44% of the patients were not taking any medication. Forty-one per cent of the patients did not have any apprehension of the reason for their RAS, while stress (15.8%) was the most common apprehended aetiological factor. Sixty-two per cent had one to three minor ulcers at one time. Forty-eight per cent reported having had a major aphthous ulcer at least once.The most frequent symptom reported was pain (53.7%), followed by a smarting sensation (18.6%) and tenderness (4%). The most common treatment for RAS was Zendium™ toothpaste/mouthrinse (28%), followed by corticosteroids (25%). Fifty-four per cent of the patients experienced no relief from the treatment. When toothpaste habits were investigated, Zendium™ was used by 32% of the patients and toothpaste containing sodium-lauryl-sulfatase was used by 32%.There was no positive correlation between the use of Zendium™ toothpaste and the relief of symptoms or the size, number or frequency of the aphthous ulcers. Sixty-four per cent of the patients had never smoked, while 7% were smokers. No positive correlation was found when age, gender, allergy, medication and smoking were correlated to the frequency, number and size of the aphthous ulcers. In conclusion, we found that the aetiology behind RAS is still unclear and probably multifactorial. Standard treatment methods like Zendium™ should perhaps be questioned and this study did not find any support for smoking as a "protective" factor, i.e. having less likelihood of experiencing major problems from RAS.

Use of observational mechanical gateway connector in spinal cord stimulation trials.

BACKGROUND: Spinal cord stimulation (SCS) is an established treatment option for chronic pain. Prior to permanent implantation, temporary trials are performed to evaluate the SCS treatment. Currently there are multiple manufacturers with varying fundamental differences in delivery and resultant paresthesias. However, trials are typically limited to one manufacturer for the patient to evaluate. OBJECTIVE: To evaluate the role of the Observational Mechanical Gateway (OMG) Connector for patients undergoing SCS trials. STUDY DESIGN: Retrospective cohort design study. Patients undergoing SCS trials were offered at the end of the 7 day trial to experience stimulation using the OMG Connector. SETTING: Academic university-based pain management center. METHOD: Participants were trialed using the OMG Connector at the end of the 7 day spinal cord stimulation trial. Data based on participants' preference were collected. RESULTS: The average pain score at baseline was 7.3 on a 10-point scale overall, with improvement during the SCS trial to 2.9 overall; 3.5 in Medtronic (MT); and 2.4 in St. Jude (SJ) SCS trials (P = 0.04). The average pain score with OMG was 2.6 overall; 2.8 in MT; and 2.4 in SJ (P = 0.28). In terms of overall coverage of pain distribution, paresthesia and overall satisfaction, the P values were 0.24, 0.21 and 0.33 respectively. Overall, 12 of 16 participants underwent permanent implantation. One of the 4 failed trials was successfully retrialed with the OMG Connector. LIMITATIONS:   Small sample of participants and the duration of the OMG Connector trial. CONCLUSIONS: The OMG Connector offers patients another opportunity to better access the available treatment options during the SCS trial period.

Predicted effects of pulse width programming in spinal cord stimulation: a mathematical modeling study.

To understand the theoretical effects of pulse width (PW) programming in spinal cord stimulation (SCS), we implemented a mathematical model of electrical fields and neural activation in SCS to gain insight into the effects of PW programming. The computational model was composed of a finite element model for structure and electrical properties, coupled with a nonlinear double-cable axon model to predict nerve excitation for different myelinated fiber sizes. Mathematical modeling suggested that mediolateral lead position may affect chronaxie and rheobase values, as well as predict greater activation of medial dorsal column fibers with increased PW. These modeling results were validated by a companion clinical study. Thus, variable PW programming in SCS appears to have theoretical value, demonstrated by the ability to increase and even 'steer' spatial selectivity of dorsal column fiber recruitment. It is concluded that the computational SCS model is a valuable tool to understand basic mechanisms of nerve fiber excitation modulated by stimulation parameters such as PW and electric fields.

The effect of pulse width and contact configuration on paresthesia coverage in spinal cord stimulation.

BACKGROUND: In spinal cord stimulation for the management of chronic, intractable pain, a satisfactory analgesic effect can be obtained only when the stimulation-induced paresthesias cover all painful body areas completely or partially. OBJECTIVE: To investigate the effect of stimulus pulse width (PW) and contact configuration (CC) on the area of paresthesia (PA), perception threshold (VPT), discomfort threshold (VDT), and usage range (UR) in spinal cord stimulation. METHODS: Chronic pain patients were tested during a follow-up visit. They were stimulated monopolarly and with the CC giving each patient the best analgesia. VPT, VDT, and UR were determined for PWs of 90, 210, and 450 microseconds. The paresthesia contours at VDT were drawn on a body map and digitized; PA was calculated; and its anatomic composition was described. The effects of PW and CC on PA, VPT, VDT, and UR were tested statistically. RESULTS: Twenty-four of 31 tests with low thoracic stimulation and 8 of 9 tests with cervical stimulation gave a significant extension of PA at increasing PW. In 14 of 18 tests (low thoracic), a caudal extension was obtained (primarily in L5-S2). In cervical stimulation the extension was predominantly caudal as well. In contrast to VPT and VDT, UR is not significantly different when stimulating with any CC. CONCLUSION: PA extends caudally with increasing PW. The mechanism includes that the larger and smaller dorsal column fibers have a different mediolateral distribution and that smaller dorsal column fibers have a smaller UR and can be activated only when PW is sufficiently large. A similar effect of CC on PA is unlikely as long as electrodes with a large intercontact distance are applied.

Physiological basis of tingling paresthesia evoked by hydroxy-alpha-sanshool.

Hydroxy-alpha-sanshool, the active ingredient in plants of the prickly ash plant family, induces robust tingling paresthesia by activating a subset of somatosensory neurons. However, the subtypes and physiological function of sanshool-sensitive neurons remain unknown. Here we use the ex vivo skin-nerve preparation to examine the pattern and intensity with which the sensory terminals of cutaneous neurons respond to hydroxy-alpha-sanshool. We found that sanshool excites virtually all D-hair afferents, a distinct subset of ultrasensitive light-touch receptors in the skin and targets novel populations of Abeta and C fiber nerve afferents. Thus, sanshool provides a novel pharmacological tool for discriminating functional subtypes of cutaneous mechanoreceptors. The identification of sanshool-sensitive fibers represents an essential first step in identifying the cellular and molecular mechanisms underlying tingling paresthesia that accompanies peripheral neuropathy and injury.

An investigation into the effects of frequency-modulated transcutaneous electrical nerve stimulation (TENS) on experimentally-induced pressure pain in healthy human participants.

UNLABELLED: Frequency-modulated transcutaneous electrical nerve stimulation (TENS) delivers currents that fluctuate between preset boundaries over a fixed period of time. This study compared the effects of constant-frequency TENS and frequency-modulated TENS on blunt pressure pain in healthy human volunteers. Thirty-six participants received constant-frequency TENS (80 pps), frequency-modulated TENS (20 to 100 pps), and placebo (no current) TENS at a strong nonpainful intensity in a randomized cross-over manner. Pain threshold was taken from the forearm using pressure algometry. There were no statistical differences between constant-frequency TENS and frequency-modulated TENS after 20 minutes (OR = 1.54; CI, 0.29, 8.23, P = 1.0). Both constant-frequency TENS and frequency-modulated TENS were superior to placebo TENS (OR = 59.5, P < .001 and OR = 38.5, P < .001, respectively). Frequency-modulated TENS does not influence hypoalgesia to any greater extent than constant-frequency TENS when currents generate a strong nonpainful paraesthesia at the site of pain. The finding that frequency-modulated TENS and constant-frequency TENS were superior to placebo TENS provides further evidence that a strong yet nonpainful TENS intensity is a prerequisite for hypoalgesia. PERSPECTIVE: This study provides evidence that TENS, delivered at a strong nonpainful intensity, increases pain threshold to pressure algometry in healthy participants over and above that seen with placebo (no current) TENS. Frequency-modulated TENS does not increase hypoalgesia to any appreciable extent to that seen with constant-frequency TENS.

Endoscopic anatomical nerve observation and minimally invasive management of cubital tunnel syndrome.

Experience with the use of the Universal Subcutaneous Endoscope (USE) system in surgical treatment of cubital tunnel syndrome in 35 patients is reported. Patients included in the study had pre- and postoperative clinical and electrophysiological data, and had undergone a minimum follow-up period of 13 months. Mean patient age was 59.5 years and the mean follow-up period was 25.9 months. The operation was performed under local anaesthesia without pneumatic tourniquet and on an out-patient basis. A 1.5 cm portal is made at the cubital tunnel and the USE system is inserted next to the ulnar nerve, first distally and then proximally. The nerve is endoscopically assessed and only the tissue that compresses the nerve is released, in keeping with the principles of minimally invasive treatment. Preoperative tingling sensations disappeared postoperatively in 63% of cases. Pain and sensory disturbance recovered to normal in 92% and 89% of cases, respectively. Abnormal motor nerve conduction velocities improved in 77%. Abductor digiti minimi weakness MMT 0, 1, 2 in 16 hands recovered to MMT 4 or 5 in eight. First-dorsal interosseous weakness in 18 hands recovered to MMT 4 or 5 in seven. There were no complications in this series. The endoscopic approach facilitates inspection of the ulnar nerve so that selective release of the tissue that compresses the nerve can readily be performed. The technique has proven effective in the treatment of cubital tunnel syndrome.

The impact of muscular variation on the neurodynamic test for the median nerve in a healthy population with Langer's axillary arch.

OBJECTIVE: The neurodynamic test of the median nerve (ULNT1) is frequently used to assess the mechanics and physiology of the brachial plexus and median nerve. The present study looks for a positive ULNT1 in a healthy population with Langer's axillary arch (LAA) and analyzes whether LAA affects the elbow extension range of motion (EE-ROM) of the ULNT1. METHOD: Of 640 volunteers screened, 26 LAA sides were finally included. Additional history taking revealed "minor symptoms" in some subjects. Minor symptoms do not qualify as a disorder because there is no interference with daily activities and no medical advice is sought. This study investigates whether the ULNT1 can (re)produce minor symptoms or abnormal responses in subjects with LAA. The EE-ROM was compared between the subjects' left and right side, and the subtraction angle-which is the effect of placing the cervical spine in contralateral lateral flexion-was compared between LAA sides and controls. RESULTS: Langer's axillary arch sides showed a significant increase in the occurrence of minor symptoms and positive ULNT1, but no influence was observed on the EE-ROM. CONCLUSIONS: These findings suggest that LAA may be capable of transiently provoking the axillary neurovascular bundle. The unaffected EE-ROM may be the consequence of a vascular origin of the minor symptoms or the consequence of an ulnar nerve/medial cord response to the ULNT1.

Occipital nerve stimulation for drug-resistant chronic cluster headache: a prospective pilot study.

BACKGROUND: Drug-resistant chronic cluster headache (drCCH) is a devastating disorder for which various destructive procedures have been tried unsuccessfully. Occipital nerve stimulation (ONS) is a new, safe strategy for intractable headaches. We undertook a prospective pilot trial of ONS in drCCH to assess clinical efficacy and pain perception. METHODS: Eight patients with drCCH had a suboccipital neurostimulator implanted on the side of the headache and were asked to record details of frequency, intensity, and symptomatic treatment for their attacks in a diary before and after continuous ONS. To detect changes in cephalic and extracephalic pain processing we measured electrical and pressure pain thresholds and the nociceptive blink reflex. FINDINGS: Two patients were pain free after a follow-up of 16 and 22 months; one of them still had occasional autonomic attacks. Three patients had around a 90% reduction in attack frequency. Two patients, one of whom had had the implant for only 3 months, had improvement of around 40%. Mean follow-up was 15.1 months (SD 9.5, range 3-22). Intensity of attacks tends to decrease earlier than frequency during ONS and, on average, is improved by 50% in remaining attacks. All but one patient were able to substantially reduce their preventive drug treatment. Interruption of ONS by switching off the stimulator or because of an empty battery was followed within days by recurrence and increase of attacks in all improved patients. ONS did not significantly modify pain thresholds. The amplitude of the nociceptive blink reflex increased with longer durations of ONS. There were no serious adverse events. INTERPRETATION: ONS could be an efficient treatment for drCCH and could be safer than deep hypothalamic stimulation. The delay of 2 months or more between implantation and significant clinical improvement suggests that the procedure acts via slow neuromodulatory processes at the level of upper brain stem or diencephalic centres.

Clinical presentation, quantitative sensory testing, and therapy of 2 patients with fourth thoracic syndrome.

OBJECTIVE: The aim of the study was to describe 2 representative cases of patients presenting to an osteopathic pain practice with signs and symptoms consistent with the fourth thoracic (T4) syndrome. In addition, this article reports the application of quantitative thermosensory testing and dynamometer strength testing to confirm associated sensory and motor strength changes. Nonmanipulative therapeutic interventions are reported for the first time. CLINICAL FEATURES: Two patients experienced paresthesias in all digits of the hands, glove-like numbness of the hands and forearm, weakness (unable to open jars), hand clumsiness, upper extremity coldness, fullness or tightness, deep aching pain, and other signs and symptoms consistent with T4 syndrome. The patients were evaluated using quantitative thermosensory testing and handgrip dynamometry before and after treatment. INTERVENTION AND OUTCOME: Relief of bilateral arm pain, numbness, and paresthesias occurred after intramuscular injections of 1 to 2 mL of 0.5% bupivacaine at the fourth thoracic paraspinal level. Additional therapy for associated signs and symptoms was provided using an anticonvulsant (gabapentin). CONCLUSION: The clinical presentation of the patients reported in this article provides a description and additional information regarding T4 syndrome.

Transcranial DC stimulation (tDCS): a tool for double-blind sham-controlled clinical studies in brain stimulation.

OBJECTIVE: Brain polarization in the form of transcranial direct current stimulation (tDCS), which influences motor function and learning processes, has been proposed as an adjuvant strategy to enhance training effects in Neurorehabilitation. Proper testing in Neurorehabilitation requires double-blind sham-controlled study designs. Here, we evaluated the effects of tDCS and sham stimulation (SHAM) on healthy subjects and stroke patients' self-report measures of attention, fatigue, duration of elicited sensations and discomfort. METHODS: tDCS or SHAM was in all cases applied over the motor cortex. Attention, fatigue, and discomfort were self rated by study participants using visual analog scales. Duration of perceived sensations and the ability to distinguish tDCS from Sham sessions were determined. Investigators questioning the patients were blind to the intervention type. RESULTS: tDCS and SHAM elicited comparably minimal discomfort and duration of sensations in the absence of differences in attention or fatigue, and could not be distinguished from SHAM by study participants nor investigators. CONCLUSIONS: Successful blinding of subjects and investigators and ease of application simultaneously with training protocols supports the feasibility of using tDCS in double-blind, sham-controlled randomized trials in clinical Neurorehabilitation. SIGNIFICANCE: tDCS could evolve into a useful tool, in addition to TMS, to modulate cortical activity in Neurorehabilitation.