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P Schnider

Publications and source records attributed to P Schnider.

At least 19 recordsLinked to original sources
PubMed2004

Botulinum toxin in the treatment of rare head and neck pain syndromes: a systematic review of the literature.

BACKGROUND: Botulinum neurotoxin (BoNT) is used to treat various neurological disorders associated with pathologically increased muscle tone. Botulinum toxin inhibits the release of the neurotransmitter acetylcholine at the neuromuscular junction thereby inhibiting striatal muscle contractions. Besides the reduction in muscle tone BoNT tends to reduce pain in pain syndromes associated with muscle spasm. In addition, BoNT has been proposed as an analgesic, suggesting alternative non-cholinergic mechanisms of action.Surprisingly, BoNT was reported as a potential treatment for tension-type headache and migraine-both primary headache syndromes without an apparent muscular component-however, varying responses to BoNT have been found, overall without sufficient evidence for a general treatment. In this systematic review we set out to clarify the efficacy and safety of BoNT in the treatment of rare head and neck pain syndromes (e. g. cervicogenic headache, chronic paroxysmal hemicrania, cluster headache, trigeminal neuralgia, temporomandibular disorders, cervical dystonia and whiplash injuries). OBJECTIVES: To assess the analgesic efficacy and safety of botulinum toxins versus other medicines, placebo or no treatment in rare head and neck pain syndromes. SEARCH STRATEGY: We searched the bibliographic databases MEDLINE, EMBASE and PASCAL Biomed to May 2003. We also reviewed the reference lists from identified articles including reviews and meta-analyses of treatment studies. Furthermore we searched booklets of scientific congresses in the field of neurology for potentially relevant studies. Additional reports were identified from the reference list of the retrieved papers, and by contacting experts in the field. SELECTION CRITERIA: Randomized controlled trials (RCTs) with any dose of BoNT for rare head and neck pain syndromes, describing subjective pain assessment as either the primary or a secondary outcome, were included in this review. DATA COLLECTION AND ANALYSIS: All trials were quality scored and two independent reviewers extracted data. Results were compared for differences, and discrepancies were resolved by discussion. MAIN RESULTS: Fourteen RCTs of BoNT in cervical dystonia were included in this review. All except one showed significant pain relief following BoNT treatment compared to placebo. Studies providing dichotomous outcome data were pooled using the Peto method. The overall effect was found to be highly significant (OR 4.795 [95% CI 5.551-6.473]). For cervicogenic headache, two RCTs-one positive study and one negative study-were included. Two studies addressing chronic neck pain were included in this review. Both studies did not reveal significant effects. Furthermore, one small trial (N = 15 patients) focussing BoNT in temporomandibular disorders was included,without demonstrating significant effectiveness but a high proportion of patients lost to follow-up and a high rate of adverse effects. For the use of BoNT in cluster headache, chronic paroxysmal hemicrania and trigeminal neuralgia no RCTs were identified. Adverse effects (AEs) were found to be mild to moderate and dose-dependent. They were summarized where possible, irrespective of the formulation used and condition treated (OR = 5.066 [95% CI 2.770-9.265], number-needed-to-harm (NNH) = 5.5 [range 4.4-17]). REVIEWERS' CONCLUSIONS: There is convincing evidence for the effectiveness of BoNT in the treatment of pain associated with cervical dystonia. Due to the frequent adverse effects predominantly observed with higher doses, the trade off in risk and benefit should be carefully considered in each case. For all other rare head and neck pain syndromes we found no RCTs (cluster headache, chronic paroxysmal hemicrania, trigeminal neuralgia) and only a few small sized trials (cervicogenic headache, chronic neck pain, temporomandibular disorders). We were therefore unable to draw any definite conclusions.

Anti-Dyskinesia Agents↗
PubMed2003

A randomized, double-blind, placebo controlled study on analgesic effects of botulinum toxin A.

OBJECTIVE: Botulinum toxin type A (BTXA) is used to treat neurologic disorders associated with increased muscle tone. Its use is often associated with pain relief. METHODS: A possible direct analgesic effect of BTXA on C and Adelta fibers was studied on 16 healthy volunteers receiving 30 U BTXA into one forearm and pure saline into the other. To exclude the secondary effect due to muscular tone reduction, BTXA was injected intradermally. Thermal sensory testing of heat pain (threshold and tolerance) and neuroselective current sensory testing of current pain threshold/tolerance were performed at baseline and 3, 14, and 28 days after treatment. Thereafter, on day 28, capsaicin was administered simultaneously into both forearms to evaluate a possible peripheral effect and central effect on pain processing and on the axon reflex flare. RESULTS: The authors observed no significant difference in any of the perception outcome measures between BTXA and placebo pretreated areas. Flare areas as a result of the release of neuropeptides after capsaicin application showed no differences. CONCLUSIONS: The results suggest that pain reduction after BTXA treatment is mediated through its effect on muscle tone rather than a direct analgesic effect.

Adult↗
PubMed2002

Relation between depression and anxiety in dystonic patients: implications for clinical management.

Past clinical research has identified depression as the most common psychiatric disorder associated with cervical dystonia (CD). The purpose of our study is to document different patterns of psychopathology, the frequency of psychiatric disorders, and possible correlation with the neurological disorder in patients with CD. Forty patients with CD were investigated to assess levels of psychopathology on two self-rated scales: the Beck Depression Inventory (BDI) and Symptom Check List (SCL-90). To determine the presence of psychiatric disorders, the patients were evaluated using the standard instrument in the DSM-III-R (Structured Clinical Interview Schedule, SCID). A small group of dystonic patients (12%) had higher levels of psychopathology, with significant amounts of concomitant anxiety and depression on the BDI and SCL-90. SCID criteria for at least one psychiatric disorder were fulfilled in 22 patients (55%), including both the lifetime and current diagnoses. The most frequent diagnostic categories were anxiety (40%) and major depressive disorders (37.5%). In 17 patients (42.5%), criteria for at least one lifetime diagnosis were fulfilled prior to the onset of CD. Psychiatric evaluation does not indicate one specific disorder associated with CD. The presence of anxiety and depression symptoms before and during the course of dystonia, without a possible causal relationship, could mean that the alteration of a chain of physiological events in the central nervous system may not lead to a single clinical picture. The relatively high overall lifetime prevalence of anxiety and depressive disorders may indicate the need for a broader diagnostic and therapeutic approach to patients with focal dystonia.

Adult↗
PubMed2002

The impact of blepharospasm and cervical dystonia on health-related quality of life and depression.

The aim of the study was to evaluate and compare health-related quality of life (HR-QoL) and depression in essential blepharospasm (BSP) and idiopathic cervical dystonia (CD), to identify the clinical and demographic factors associated with poor HR-QoL in both disorders and to analyse the effect of Botulinum Toxin A (BtxA) therapy. Two hundred-twenty consecutive patients with BSP (N = 89, 62 % women, mean age 64 years, mean disease duration 7 years) and CD (N = 131, 64 % women, mean age 53 years, mean disease duration 8 years) recruited from routine referrals to eight Austrian dystonia clinics were included. HR-QoL was measured by the Short Form 36 (SF-36) and depression by the Beck Depression Inventory (BDI). At baseline, patients with CD and BSP scored significantly worse in all eight SF-36 domains compared with an age-matched community sample. In addition, 47 % of patients with CD and 37 % of those with BSP were depressed. Women with BSP scored significantly lower in all SF-36 domains and were more depressed than male patients. In contrast, there was no significant effect of gender on HR-QoL and depression in CD. Neck pain had a significant impact on all SF-36 domains and represented the main determinant of depression in CD. Although BtxA therapy resulted in a significant improvement of clinical symptoms in BSP and CD, HR-QoL did not improve in BSP and only two of the eight SF-36 domains improved significantly in patients with CD. The present study for the first time demonstrated that BSP has a substantial impact on health status emphasizing the need for psychological support with interventions aimed at treating depression in these patients. Our results provide further evidence for the profound impact of CD on HR-QoL and indicate the importance of an adequate management of neck pain in addition to reducing the severity of dystonia in CD. The mismatch between objective BtxA derived improvement of dystonia and lack of change of HR-QoL as determined by the SF-36 illustrates the need for optimized disease specific quality of life rating scales in patients with craniocervical dystonia.

Aged↗
PubMed2001

Efficacy and safety of a standardised 500 unit dose of Dysport (clostridium botulinum toxin type A haemaglutinin complex) in a heterogeneous cervical dystonia population: results of a prospective, multicentre, randomised, double-blind, placebo-controlled, parallel group study.

Results from a dose-ranging study in a selected group of de novo patients with rotational cervical dystonia (CD) suggest that 500 units of Dysport (Clostridium botulinum toxin type A haemaglutinin complex) is the optimal starting dose. The present study aimed to confirm the efficacy and safety profile of this dose in a population of CD patients more representative of those seen in a typical dystonia clinic. A total of 68 patients with moderate to severe CD (Tsui score > or = 9) were randomly assigned to receive placebo or Dysport 500 units. Treatment was administered according to the clinical pattern of head deviation, using a standardised injection protocol. A total of 21 patients (11 Dysport, 10 placebo) had not previously received botulinum toxin type A (BtxA) injections, and 47 patients (24 Dysport, 23 placebo) had received BtxA more than 12 weeks previously. Assessments were performed at baseline and weeks 4, 8 and 16. Patients defined as non-responders at week 4 were re-treated in an open phase with 500 units of Dysport at week 6, and were followed up at week 10. Significant between-group differences in Tsui scores were present at weeks 4 (p=0.001) and 8 (p=0.002). Similarly, there were significant between-group differences (p < 0.001) in patient and investigator assessments of response in favour of Dysport at weeks 4 and 8. Also, more Dysport (49%) than placebo (33%) patients were pain-free at week 4 (p=0.02). Overall, 30/35 (86 %) Dysport patients and 14/33 (42%) placebo patients were classified as responders at week 4. Adverse events were reported by 15/35 Dysport patients and 9/33 placebo patients. Open phase treatment produced improvements in Tsui (p < 0.001) and pain scores (p=0.011), and 23/24 patients were classified as responders. Although individual dose titration and muscle selection is desirable, this study demonstrated that a dose of 500 units of Dysport injected into clinically identified neck muscles without electromyographic guidance is safe and effective in the treatment of patients with the major clinical types of cervical dystonia.

Adolescent↗
PubMed2001

Treatment of focal hyperhidrosis with botulinum toxin type A: long-term follow-up in 61 patients.

BACKGROUND: The blocking action of botulinum toxin type A (BTX-A) on cholinergically innervated sweat glands has been used successfully to treat patients with focal hyperhidrosis. OBJECTIVES: To investigate the long-term efficacy and safety of intradermal injections of BTX-A. METHODS: We performed an open-label study in 61 patients treated over a period of 3 years for axillary or palmar hyperhidrosis. A total dose of 400 mU BTX-A (Dysport) was injected into both axillae or 460 mU BTX-A (Dysport) into both palms. The injections were repeated after relapse. Objective quantification of sweat production was performed using digitized ninhydrin-stained sheets. RESULTS: Four weeks after BTX-A treatment the median reduction in sweat production was 71% compared with baseline (P < 0.001) in the axillary group and 42% (P = 0.005) in the palmar group. Subjective assessment of sweat production by the patients using a visual analogue scale (0, no sweating; 100, the most severe sweating) showed a significant reduction in both the axillary (P < 0.001) and palmar groups (P < 0.001). Secondary disturbances due to focal hyperhidrosis interfering with daily activities were markedly improved in both groups. The median time interval between the sets of injections was 34 weeks for axillary hyperhidrosis and 25 weeks for palmar hyperhidrosis. The treatment of palmar hyperhidrosis was complicated by transient but not disabling weakness of the small hand muscles in nine of 21 patients. CONCLUSIONS: Repeated intradermal injections of BTX-A in patients with axillary and palmar hyperhidrosis are as effective as first treatments.

Adult↗
PubMed2001

Are there predictive factors for long-term outcome after withdrawal in drug-induced chronic daily headache?

OBJECTIVES: To investigate prognostic factors for long-term outcome of patients after inpatient withdrawal because of drug-induced chronic daily headache. PROCEDURES: Fifty-five patients (36 females) were re-examined by means of a standardized interview after inpatient withdrawal. The mean observation period was 9.28 +/- 2.85 years (mean +/- SD; median 8.58; range 5.00-13.50). RESULTS: Five years after withdrawal, one-third of the patients (34.6%) had an overall favourable outcome, one-third (32.7%) had no recurrent drug overuse and reported a clear-cut improvement of headache, and one-third (32.7%) developed recurrent drug overuse. Most relapses occurred within 2 years, and a small percentage within 5 years. No predictors for long-term outcome after inpatient withdrawal were found. CONCLUSIONS: All patients with drug-induced chronic daily headache should be considered as good candidates for inpatient withdrawal, and no patient should be excluded from that therapy.

Adult↗
PubMed2001

To do or not to do? Magnetic resonance imaging in mild traumatic brain injury.

Clinical quantification of mild traumatic brain injury (MTBI) patients should be based on Glasgow coma scale (GCS) score, duration of loss of consciousness (LOC) and post-traumatic amnesia (PTA). In addition, a short practicable neuropsychological test might be useful in detecting minor memory and attentional deficits. MRI appears to be the most sensitive imaging method for assessing MTBI so far, but information regarding a visualized lesion is not usually utilized in the classification of MTBI. Magnetic resonance imaging (MRI) should, therefore, play a major role in any MTBI classification scheme. An appropriate MRI protocol has to be chosen using at least T1 weighted, T2 weighted, proton density and gradient-echo (GRE) sequence images, all in at least two planes, in order to detect and classify all lesions precisely. Owing to the fact that acute lesions may be missed, it is advisable to perform MRI in the first 2 weeks following trauma. Further research is necessary to clarify the relationship between chronic symptoms after MTBI and MRI abnormalities. It may, thus, be possible to provide optimal strategies for emergency department management, to define a group of patients with a need for acute and rehabilitative intervention after MTBI, and to predict their outcome.

Adolescent↗
PubMed2001

[Treatment of the spastic drop foot with botulinum toxin type A in adult patients].

Spastic drop foot can be managed by physical measures, local pharmacological agents, oral anti-spastic drugs and surgical procedures. Recent studies have documented the clear effect of botulinum toxin type A (BTX-A) in the treatment of the spastic drop foot, particularly by reducing the resistance against passive movement and increasing the range of motion. Functional benefit and pain reduction have also been observed. The use of BTX-A is safe and free of serious side effects. Individual realistic treatment goals must be defined by the rehabilitation team before the treatment. Possible purposes of the treatment are the achievement of a straight foot to allow weight bearing or application of an orthosis and to reduce the premature activation of the calf muscles during gait. Other treatment goals are the facilitation of nursing care, as well as physical and occupational therapy. BTX-A injections can reduce pain, and prevent pressure ulcers or surgical interventions. Early physiotherapy or occupational therapy may increase the treatment effect of BTX-A. Close cooperation between the neurologist, physiotherapist, occupational therapist, nursing staff and other multidisciplinary rehabilitation team members is essential to maximize the benefit for the patients.

Adult↗
PubMed2001

[Botulinum toxin in the treatment of focal hyperhidrosis].

INTRODUCTION: Botulinum A toxin (BTX-A) acts primarily at peripheral cholinergic synapses, inhibiting the release of acetylcholine. Initially it has been used to block the neuromuscular junction in focal dystonic and spastic syndromes. Recently there has been suggestions for potential clinical indications in non-muscular diseases where cholinergic terminals play a role. GUSTATORY SWEATING: In 1995 physicians reported a long-lasting anhidrotic effect of intracutaneous BTX-A injections in patients suffering from gustatory sweating (Frey's syndrome). Consequently, a number of clinical studies demonstrated good efficacy of intradermal injections of botulinumtoxin in patients with focal hyperhidrosis. FOCAL HYPERHIDROSIS OF THE PALMS AND AXILLAE: Focal hyperhidrosis is usually confined to the palms and axillae. Excessive sweating may be a social handicap and an occupational hazard. The management of focal hyperhidrosis remains controversial. Topical antiperspirants are only effective in very mild cases. Iontophoresis with tap water or anticholinergic drugs is messy and time consuming with only short-lived effect. Sympathectomy, the cornerstone of surgical management, is usually effective in palmar hyperhidrosis. Complications of this technique include surgical risks, postoperative and cosmetic problems and compensatory hyperhidrosis. AXILLARY HYPERHIDROSIS: Several studies confirmed that intracutaneous injections of botulinum toxin are useful in the majority of patients with axillary hyperhidrosis resistant to conventional treatment. In axillary hyperhidrosis total doses are ranging from 200-400 mU Dysport or from 80 to 130 mU Botox to reach a good clinical response. Injections are usually well tolerated and no serious side-effects have been observed. The mean duration of anhidrotic effect ranges between 3 and 9 weeks. PALMAR HYPERHIDROSIS: The use of botulinumtoxin in patients with palmar hyperhidrosis is rather difficult. The therapeutic window is smaller because injections are complicated by transient weakness of the small hand-muscles. Furthermore the injections at the palms are painful which can be overcomed by application of local anaesthetics or the blockade of the ulnar and median nerves. The duration of anhidrotic effect ranges from 20 to 50 weeks. CONCLUSION: Intracutaneous injections of botulinum-toxin should be offered to patients with focal hyperhidrosis of the palms and axillae causing serious social, psychologic and occupational problems, resistant to other conventional treatment options.

Axilla↗
PubMed2000

Enantioselective hydrogenation of olefins with phosphinooxazoline-iridium catalysts.

Cationic iridium complexes with chiral phosphinooxazoline ligands are efficient catalysts for the enantioselective hydrogenation of olefins. The complexes are readily prepared, air-stable, and easy to handle. In contrast to chiral rhodium- and ruthenium-phosphine catalysts, they do not require the presence of a polar coordinating group near the C=C bond. In the hydrogenation of unfunctionalized trisubstituted 1,2-diaryl-olefins, high enantioselectivities of >95% ee with full conversion and turnover frequencies of >7,000 h-1 can be achieved, using 0.1 mol% of catalyst with tetrakis[3, 5-bis(trifluoromethyl)phenyl]borate (TFPB or BARF) as the counterion. The corresponding hexafluorophosphate or tetrafluoroborate salts give low conversion due to deactivation of the catalyst during the reaction. Substrates with polar substituents such as allylic alcohols, on the other hand, afford better results with the hexafluorophosphate salts.

Journal Article↗
PubMed2000

Bladder volume determination: portable 3-D versus stationary 2-D ultrasound device.

OBJECTIVE: To investigate how accurately a portable three-dimensional (3-D) scanner and a multipurpose two-dimensional (2-D) real-time scanner determined bladder volumes. STUDY DESIGN: Prospective, controlled clinical trial, single-blind, crossover design. SETTING AND PARTICIPANTS: Twenty-three inpatients with permanent bladder catheters participated voluntarily in this study. METHODS: The bladders of 20 patients were filled through an indwelling catheter with 60, 110, 160, 210, and 260 mL sterile normal saline. Volumes were measured twice with each device. Measurements were compared with the actual bladder volumes. RESULTS: The 2-D device showed better reproducibility, particularly at lower bladder volumes. The 3-D scanner showed a significant difference between the two measurements at 160 mL (p<.05) and had poor reproducibility at 110, 210, and 260 mL. Both devices overestimated actual bladder volume at fillings of <160 mL and underestimated it at fillings of > or =160 mL. The range between the 25th and 75th percentiles was always larger for the 3-D scanner, except for the 210 mL reading. CONCLUSION: Both devices showed sufficient accuracy for clinical practice. Ultrasound measurements of >110 mL should be followed by catheterization to detect potentially harmful bladder volumes.

Cross-Over Studies↗