Botulinum Toxin Type A Application Research Articles

The efficacy of botulinum toxin in neuropathic pain: a systematic review

Introduction Neuropathic pain (NP) is characterised as a lesion or disease directly affecting the somatosensory system. This study aims to analyse the efficacy of botulinum toxin type A (BT-A) in the treatment of neuropathic pain. Methods This systematic literature review, guided by PRISMA, applied the PICO strategy with the following criteria: (P = patients with neuropathic pain, I = botulinum toxin, C = placebo or active drug, and O = pain relief). Results Fourteen articles, all randomised controlled trials with a placebo control, were included in the review. A total of 645 patients were randomised, with 353 patients receiving treatment with botulinum toxin type A in doses ranging from 25U to 400U. The evaluated studies addressed trigeminal neuralgia, diabetic polyneuropathy, post-herpetic neuralgia, spinal cord injury, phantom limb pain, and peripheral neuropathic pain after trauma or surgery. Conclusion BT-A has emerged as a promising treatment for various origins of neuropathic pain. Therefore, future studies should adopt stricter criteria regarding dosage and routes of administration to ensure effective and consistent BT-A application.

Optimizing Botulinum Toxin A Administration for Forehead Wrinkles: Introducing the Lines and Dots (LADs) Technique and a Predictive Dosage Model.

This study introduces the Lines and Dots (LADs) technique, a new approach for administering botulinum toxin type A (BoNT-A) in treating forehead wrinkles. (1) Background: BoNT-A application patterns in the forehead often rely solely on the anatomy of the frontalis muscle. The LADs technique proposes a combination of anatomical features with nerve pathways. (2) Methods: The technique employed a grid system aligned with the supraorbital and supratrochlear nerve pathways and used an electronic acupuncture pen for validation. This study analyzed treatment outcomes for efficacy and safety and proposed a predictive model for BoNT-A dosage. (3) Results: LADs was associated with a high satisfaction rate and low side effect incidence. The predictive model followed BoNT-A Units=0.322×Muscle Pattern Code+1.282×Line Type Code+2.905×Severity Pre-Treatment+3.947. (4) Conclusions: The LADs technique offers an alternative approach to treating forehead wrinkles, optimizing efficacy while minimizing the BoNT-A dose required.

Volumetry after botulinum toxin A: the impact on abdominal wall compliance and endotracheal pressure.

Botulinum toxin type A (BTA) is an adjuvant tool used in the preoperative optimization of complex hernias before abdominal wall reconstruction (AWR). This study aims to investigate changes in the abdominal cavity and hernia sac dimensions after BTA application. A prospective study with 27 patients with a hernia defect of ≥ 10cm and loss of domain (LOD) ≥ 20% underwent AWR. Computed tomography (CT) measurements and volumetry before and after the application of BTA were performed. Intraoperative and postoperative outcomes were evaluated. Imaging post-BTA revealed hernia width reduction of 1.9cm (p = 0.002), lateral abdominal wall muscle elongation of 3.1cm (p < 0.001), hernia volume reduction (HV) from 2.9 ± 0.9L to 2.4 ± 0.8L (p < 0.001), increase in abdominal cavity volume (ACV) from 9.7 ± 2.5L to 10.3L ± 2.4L (p = 0.003), and a reduction in the HV/ACV ratio from 30.2 ± 5% to 23.4 ± 6% (p < 0.001). Fascial closure was achieved in 92.6% of cases and component separation was required in 78%. The average variation in pulmonary plateau pressure was 3.53 cmH2O, and there were no postoperative respiratory failure recorded. At the 90-day follow-up, the wound morbidity rate was 25%, unplanned readmissions were 11%, and hernia recurrence 7.4%. BTA produces measurable volumetric changes in abdominal wall and appears to facilitate fascial closure. Further studies are required to determine the role of BTA in the surgical armamentarium for complex hernia repair.

Does injection pattern matter in upper face BoNT-A application? A prospective split-face andomized trial comparing linear and spot technique.

Although the efficacy of botulinum toxin type A (BoNT-A) has been shown to vary depending on injection layer, reconstitution volumes, and BoNT-A formulations, the impact of injection patterns has been rarely mentioned. This article compared the therapeutic effects in patients treated with BoNT-A with retrograde linear and traditional spot injection techniques. Twenty-eight participants were enrolled in a split-face, patient-blinded randomized clinical trial. Each patient received BoNT-A injected with linear injection technique on one side and with spot injection technique on the other side. Outcomes included the wrinkle improvement rates (WIR) of the two injection techniques determined by the wrinkle scores derived from Antera 3D camera, the muscle activity assessed via ultrasound, and patient-reported pain rating on a numeric pain rating scale (NRS). All participants completed the study. For forehead wrinkles, WIR on the linear side was significantly larger than that on the spot side at 1 week and 1 month (p<0.02). For glabellar wrinkles, WIR on the linear injection side was significantly larger than that on the spot side at 1 week (p=0.04). However, for periorbital wrinkles, WIR on the spot side was significantly larger than that on the linear side at 1 week (p<0.03). No significant difference was observed between the injection patterns in terms of muscle contraction and NRS scores. Compared with the traditional spot injection, the retrograde linear injection shows to be superior in reducing forehead lines and glabellar lines, but less effective in reducing periorbital lines when identical dosages were injected. chictr.org.cn: ChiCTR2100046880.

Ultrasound-guided injection of botulinum toxin type A blocks cardiac sympathetic ganglion to improve cardiac remodeling in a large animal model of chronic myocardial infarction

Strategies to improve various cardiovascular diseases by blocking cardiac sympathetic ganglion have been increasingly available currently. Botulinum toxin type A (BTA), a typical neurotoxin, has been shown to block neural transmission in a safe and long-lasting manner. The aim of the present preclinical study was to assess the efficacy of BTA microinjection to alleviate cardiac remodeling after chronic myocardial infarction (MI) by blocking cardiac sympathetic ganglion in a canine model. Beagles were randomly divided into a control group (saline microinjection with sham surgery), an MI group (saline microinjection with MI), and an MI + BTA group (BTA microinjection with MI). Ultrasound-guided percutaneous BTA or saline injection into the left stellate ganglion (LSG) was performed followed by MI induction via left anterior descending artery occlusion (LADO) or sham surgery. After 30 days, electrocardiography, Doppler echocardiography, LSG function, neural activity, and ventricular electrophysiological detection were performed in all experimental dogs. At the end, LSG and ventricular tissues were collected for further detection. BTA treatment significantly inhibited LSG function and neural activity and improved heart rate variability. Additionally, BTA application alleviated ventricular remodeling, ameliorated cardiac function, and prevented ventricular arrhythmias after 30-day chronic LADO-induced MI. Ultrasound-guided percutaneous microinjection of BTA can block cardiac sympathetic ganglion to improve cardiac remodeling in a large animal model of chronic LADO-induced MI. Ultrasound-guided BTA microinjection has potential for clinical application as a novel cardiac sympathetic ganglion blockade strategy for MI.

Bladder Dysfunction in Older Adults: The Botulinum Toxin Option.

Bladder dysfunction, which involves inadequacies of urine storage or emptying, increases with age. Conventional medications may have insufficient efficacy for patients with refractory lower urinary tract symptoms, and their concomitant adverse events (AEs) may be intolerable for the older adult population. For decades, the botulinum toxin type A (BoNT-A) injection has been an option for managing urine frequency, urge incontinence, and voiding dysfunction in the general population refractory to conventional management. This review focuses on studies of BoNT-A application in the management of bladder dysfunction in older adult patients aged ≥ 65years. In this target population, intravesical BoNT-A injections provide similar efficacy in idiopathic overactive bladder to that in younger adults. Good clinical response has also been demonstrated in older adult patients presenting with storage dysfunction and with various concomitant underlying neurological diseases. However, caution must be taken for the AEs that occur after intravesical BoNT-A injection, including increased post-void residual urine, acute urine retention, and urinary tract infection. Most evidence shows that age is not a major determinant of AEs after adjusting for other factors. In contrast to its application in storage dysfunction, evidence for voiding dysfunction in older adults is scarce. In general, BoNT-A may be a reasonable option for older adult patients with refractory storage dysfunction because of its promising clinical response without significant systemic AEs. Overall, clinicians should be aware of the balance between the therapeutic efficacy of BoNT-A and local AEs in vulnerable members of this population.

Evaluation of the botulinum toxin effects in the correction of gummy smile 32 weeks after application

Introduction: The use of botulinum toxin type A (BTX-A) to correct gummy smile has become popular in recent years. Objective: To evaluate the effects of BTX-A application in the correction of gummy smile 2 and 32 weeks after application. Methods: The sample comprised 35 patients (30 female, 5 male) at a mean age of 25.51 years (±5.59) with gummy smile due to muscular hyperfunction. In each patient, 2U of botulinum toxin was applied in the levator labii superioris alaeque nasi, 2 mm from the nasolabial fold. Photographs of spontaneous smiles were taken at 3 stages: before, 2 and 32 weeks after BTX application. Measurements of the gingival display were performed with the Radioface Studio 2 Software, and the calibration used the actual size of the right maxillary central incisor. Comparison of the three stages evaluated was performed with repeated measures ANOVA and Tukey tests. Results: Gingival display decreased significantly 2 weeks after BTX-A application and increased after 32 weeks but did not return to the initial value. Conclusion: There was a significant improvement in gummy smile 2 weeks after botulinum toxin application, and a significant relapse in the gingival display after 32 weeks, however not returning to baseline values.

Therapeutic effects of botulinum toxin type A in subjects with gummy smile: A longitudinal sEMG approach

To evaluate the response of the myoelectric activity of levator labii superioris (LLS), levator labii superioris alaeque nasi (LLSAN), and minor zygomatic (Zm) muscles in individuals with gummy smile, volunteers to botulinum toxin type A (BTX-A) application, with a follow-up of 6 months. Thirteen individuals were submitted to clinical evaluation and photographic records to monitor the variations of the gingival display (GD) during posed smile. The recording of the surface electromyography (sEMG) signal of muscles studied was performed in three tasks: posed smile (PS), upper lip elevation (ULE) and nose wing elevation (NWE). The root-mean-square value, an amplitude sEMG signal parameter, was extracted from the sEMG signals. One and three-way ANOVA were applied, and the level of significance set at 5%. There were significant differences (P<0.05) in the sEMG signal activity from the control condition (before BTX-A application - T0) to the 8th week of follow up, which was accompanied by clinical evaluation for the gingival display (P<0.05). The peak of the reduction in sEMG signals occurred 2 weeks after T0 for all the studied tasks, with the exception of the left hemiface in the PS, which showed a peak of reduction 4 weeks after T0. BTX-A led to a decrease in the sEMG signal amplitude over 2 to 4 weeks after application in the muscles, although differently concerning each hemiface when recruited to perform other mouth tasks. During the PS, the recruitment level of the upper lip elevator muscles was compatible with the clinical response obtained in the follow-up period in this study, which corroborates the sEMG assessment to clinical data.

Is low dose of botulinum toxin effective in controlling chronic pain in sleep bruxism, awake bruxism, and temporomandibular disorder?

ABSTRACT Objective To evaluate the effects of low doses of botulinum toxin type A (BoNT-A) to control pain in patients with sleep bruxism (SB), awake bruxism (AB), and temporomandibular disorder (TMD) during 180 days. Methods Overall sample of thirty-five patients with chronic pain related to TMD, SB, and AB received a single dose of 20 U of BoNT-A in masseter and temporalis muscles. The pain was assessed with a visual analog scale (VAS) before and after 15, 30, 60, 90, and 180 days of the application. Results The three clinical conditions experienced decrease in pain after 15 days of treatment (p < 0.0001); the maximum pain relief persisted for up to 90 days after BoNT-A application in patients with SB and AB and 15 days for patients with TMD. Conclusion A low dose of BoNT-A may be effective for controlling chronic pain related to SB and AB, but TMD pain reduction was short-lived.

Effect of botulinum toxin on quality of life of patients with chronic myofascial pain.

Aim: This prospective controlled clinical study aimed to evaluate the effect of botulinum toxin TypeA (BTX-A) on pain control and quality of life (QoL) in patients with chronic myofascial pain. Materials& methods: Patients with chronic myofascial pain were randomly divided into two groups (n=20): counseling and self-careand Michigan-type occlusal splint(MOS)(CG-control group) or BTX-A injection (BTX-AG). The pain was evaluated with visual analogue scaleand QoL with the oral health impact profile-14 (OHIP-14) questionnaire. Results: In both groups, the pain was reduced, and QoL improved after 30days. The results of social disability and handicap were better for patients treated with counseling and self-care and MOS. Conclusion: Minimally invasive strategies and BTX-A application improved QoL and alleviated myofascial pain.

Effect of Botulinum Toxin Type A on Mandibular Fracture Healing: An Experimental Study in Rabbits

The effect of botulinum toxin type A (BTX-A) on fracture healing of the long bones is controversial, and no controlled clinical or experimental study has investigated the effect of BTX-A on mandibular fractures. The purpose of this study was to investigate whether BTX-A injection into the masseter muscles affects bone healing by reducing the displacing forces in an unfavorable mandibular fracture model. Forty-eight male New Zealand white rabbits were used. Ten units of BTX-A was injected into each masseter muscle in the animals in the BTX-A group, whereas saline solution was injected in the animals in the control group. A unilateral osteotomy and fixation with a microplate were performed. Bone healing was evaluated by radiodensitometric, biomechanical, histologic, and histomorphometric methods after 21days. The mean bone mineral density in the fracture area was significantly higher in the BTX-A group (P=.038). The mean failure load and bending modulus values were significantly higher in the BTX-A group than in the control group (P=.032 and P=.005, respectively). The mean histologic bone healing scores, bone volume-total volume values, and trabecular diameter values were significantly higher in the BTX-A group than in the control group (P=.001, P=.001, and P=.026, respectively). BTX-A application into the masseter muscles improves bone healing of a unilateral mandibular fracture in rabbits.

USE OF BOTULINUM TOXIN A AND SUBSEQUENT REHABILITATION IN AMBULATORY CHILDREN WITH SPASTIC CEREBRAL PALSY – EFFECTS AND DILEMMAS

The definition of cerebral palsy (CP) includes a group of permanent developmental disorders of movement and posture that cause activity limitation due to non-progressive lesions in the developing fetal or newborn infant brain. The most common type of CP is spastic cerebral palsy (SCP). One of the primary aims in treating children with SCP is to enable them to perform functional activities, to stimulate effective movement, to prevent deformities of bone and joint system, and to reduce pain. Limb deformities are the most prominent manifestation in children with SCP, greatly preventing them from performing activities of daily living. The reduction of spasticity and prevention of contractures, the development of performing functional activities in the full potential, as well as delays in performing surgical intervention, have dramatically increased the use of botulinum toxin type A (BTA) in treating children with CP lately. It is known as the most potent neurotoxin found in nature that reduces spasticity after application and results in irreversible denervation at the neuromuscular junction, while functional recovery is time limited. In that time period it is necessary to evaluate the functional motor status of a child, clearly and realistically define aims in cooperation with parents, and apply adequate rehabilitation protocol. The international consensus statement in 2010 defined the protocol, dosage, the site of application, and rehabilitation protocol. After being used for two and a half decades, certain dilemmas arose, particularly those regarding rehabilitation effects after BTA application.

Treatment of Post-Facelift Facial Paralysis With Botulinum Toxin Type A

BACKGROUND: Nerve injuries post-facelifts are rare but cause serious functional and psychological impairment of self-esteem and quality of life.1,2 Despite being temporary in most cases, facial asymmetry typically lasts for 3 months. We present a treatment protocol for post-facelift facial nerve injuries using botulinum toxin type A (BTXA). MATERIALS AND METHODS: The study was conducted from January 2002 to June 2018. Nine patients (all female; mean age, 58 ± 8.4 years) with asymmetries due to post-rhytidectomy facial palsies were treated in the nonparalyzed side with abobotulinum toxin type A, with 6-month to 5-year follow-up. The 500-U vial was diluted in 4 ml of 0.9% saline. We considered 0.02 ml of the solution (2.5 abobotulinum toxin units) as 1 volume unit. Patients were examined after 15 days for outcomes evaluation. The dose applied to each muscle group1 varied from 1 to 2 volume unit per point. Patients were retreated after 5–6 months in case of asymmetry recurrence. RESULTS: Four patients sought early care (mean, 14.2 ± 6.4 days postoperative, ranging from 5 to 21 days). The others arrived later (mean, 225 ± 80.7 days postoperative, ranging from 150 to 360 days). Two patients had lesions affecting the upper third of the face, and symmetry was achieved after unilateral treatment of the frontalis muscle. Three patients had injury in the middle third; their treatment depended of analysis of the deviation vectors when smiling and frowning, as to decide which muscle groups should be treated (vertical: upper lip lifter muscles; upper oblique: lifters of the angle of the mouth muscles; and horizontal: risorius muscle). Four patients were affected in the lower third (inferior deviation vectors) and were treated with 2 points to paralyze the lower lip depressor muscles. Correction of asymmetry was achieved in all cases. Recovery from the nerve injury and BTXA application occurred symmetrically in both sides of the face in the following months. All patients with early onset of BTXA therapy (<30 days) had complete recovery of facial symmetry with a single application, evidence of neuropraxis. Patients with lesions of the upper third, those with late onset of BTXA treatment (>30 days), and those with >1 affected nervous branch presented definitive lesion, with partial recovery or improvement, and needed BTXA treatment every 6 months. CONCLUSION: Most facial nerve injuries post-facelifts presented favorable evolution for spontaneous resolution, except in the upper third of the face and in case of late lesions. Symmetry was achieved in all cases with low doses of BTXA in the suggested protocol points, avoiding an unhappy asymmetric patient in the following months. REFERENCES: 1. Salles AG, Toledo PN, Ferreira MC. Botulinum toxin injection in long-standing facial paralysis patients: improvement of facial symmetry observed up to 6 months. Aesthetic Plast Surg. 2009;33:582–590. 2. do Nascimento Remigio AF, Salles AG, de Faria JCM, et al. Comparison of the efficacy of onabotulinumtoxinA and abobotulinumtoxinA at the 1: 3 conversion ratio for the treatment of asymmetry after long-term facial paralysis. Plast Reconstr Surg. 2015;135:239–249.

Botulinum Toxin Modulates Posterior Parietal Cortex Activation in Post-stroke Spasticity of the Upper Limb.

Post-stroke spasticity (PSS) is effectively treated with intramuscular botulinum toxin type A (BoNT-A), although the clinical improvement is likely mediated by changes at the central nervous system level. Using functional magnetic resonance imaging (fMRI) of the brain, this study aims to confirm and locate BoNT-A-related changes during motor imagery with the impaired hand in severe PSS. Temporary alterations in primary and secondary sensorimotor representation of the impaired upper limb were expected. Thirty chronic stroke patients with upper limb PSS undergoing comprehensive treatment including physiotherapy and indicated for BoNT treatment were investigated. A change in PSS of the upper limb was assessed with the modified Ashworth scale (MAS). fMRI and clinical assessments were performed before (W0) and 4 weeks (W4) and 11 weeks (W11) after BoNT-A application. fMRI data were acquired using 1.5-Tesla scanners during imagery of finger-thumb opposition sequences with the impaired hand. At the group level, we separately modeled (1) average activation at each time point with the MAS score and age at W0 as covariates; and (2) within-subject effect of BoNT-A and the effect of time since W0 as independent variables. Comprehensive treatment of PSS with BoNT-A significantly decreased PSS of the upper limb with a maximal effect at W4. Task-related fMRI prior to treatment (W0) showed extensive activation of bilateral frontoparietal sensorimotor cortical areas, bilateral cerebellum, and contralesional basal ganglia and thalamus. After BoNT-A application (W4), the activation extent decreased globally, mostly in the bilateral parietal cortices and cerebellum, but returned close to baseline at W11. The intra-subject contrast revealed a significant BoNT-A effect, manifesting as a transient decrease in the activation of the ipsilesional intraparietal sulcus and superior parietal lobule. We demonstrate that BoNT-A treatment of PSS of the upper limb is associated with transient changes in the ipsilesional posterior parietal cortex, possibly resulting from temporarily altered sensorimotor upper limb representations.

Traitement de la rétraction palpébrale supérieure associée à l’ophtalmopathie dysthyroïdienne en phase active inflammatoire avec l’injection de toxine botulique A

To evaluate the efficacy of transconjunctival botulinum toxin type A (BTX-A) in the treatment of upper eyelid retraction in the active inflammatory phase of dysthyroid orbitopathy, establish the ideal dose, and evaluate side effects. This is a comparative, prospective study in patients with thyroid orbitopathy, conducted at the Conde Ophthalmology Institute in Valenciana, Mexico. The patients included had dysthyroid orbitopathy in the inflammatory phase, and they were treated with subconjunctival injection of botulinum toxin type A (BTX-A) in the upper eyelid. Five units (group 1) and ten units (group 2) of BTX-A, in a single subconjunctival dose were applied to the non-dominant eye. We evaluated visual acuity, margin-to-reflex distance (RPM1), crease height, ocular motility, diplopia and keratitis, before and after administration of the toxin. The patients were followed at one, 4 and 16 weeks, with the Student t-test as a statistical analysis. At week 4, 15 patients (100%) showed a reduced margin to reflex distance. The mean result for group 1 was -1.75mm (range -1 to -2.5mm) and group 2 was -2mm (range -1 to -4mm). Statistically significant differences were seen between pre-treatment and week 4 in both groups, but no differences between doses. Complete improvement of keratitis and lagophthalmos was observed in 5 and 2 patients, respectively. Visual acuity, ocular motility and crease height did not change in 93% of the patients. One patient (group 1) exhibited complete ptosis and vertical diplopia, which resolved spontaneously at week 6. Transconjunctival BTX-A application is safe and effective for the treatment of eyelid retraction in dysthyroid orbitopathy. No difference was found between doses. No severe side effects were reported.

Knee flexion contracture treated with botulinum toxin type A in patients with haemophilia (PWH).

Knee flexion contracture (KFC) remains a common complication of haemoarthrosis in children and young adults with haemophilia. If the KFC is not treated properly it produces disability, postural and gait abnormalities. Evaluate the effectiveness of conservative treatment of KFC with Botulinum toxin type A (BTX-A) in PWH. Seventeen patients were treated, with 21 affected knees. Mean age was 26 years. The mean follow up was 12 months. We evaluated flexion and KFC pretreatment BTX-A and up to 12 months posttreatment. BTX-A application was in hamstring and calf muscles. To evaluate the function, a questionnaire about different activities was made, and it was checked 3, 6 and 12 months after BTX-A. According to the degree of KFC, knees were divided into 3 groups: Group 1: -10° to -30° (n = 10), Group 2: -31° to -45° (n = 6) Group 3: -46° or more (n = 5). The average KFC improved from -38° to -24°. The improvement was 14° (P < 0.001). The average KFC improvement was 9° in group 1, 17° in group 2, and 23° in group 3. There was a high correlation between the improvement in KFC and the total score of the questionnaire R = 0.77. Treatment of KFC with BTX-A improves knee-related functional activities, with the advantage of being a low-cost procedure and easy to apply.

Anterior knee pain caused by patellofemoral pain syndrome can be relieved by Botulinum toxin type A injection

To investigate the therapeutic effects of Botulinum toxin type A (BTA) for anterior knee pain caused by patellofemoral pain syndrome (PFPS). Prospective case control study for intervention. A tertiary hospital rehabilitation center. Twelve bilateral PFPS patients with anterior knee pain were recruited. The worse pain knee was selected for injection, and the counterpart was left untreated. Injection of BTA to vastus lateralis (VL) muscle. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was used to assess pain, stiffness, and functional status of the knee, and CYBEX isokinetic dynamometer to assess isokinetic muscle force before and after BTA application to VL. Remarkable improvement after receiving BTA injection was obtained not only in the questionnaire of WOMAC (p<0.05), but also in knee flexion torque (p<0.05). No significant change of knee extension torque was noted (p=0.682). BTA injection is a good alternative treatment to improve anterior knee pain, knee function and isokinetic flexion torque.

Intrinsic properties and functional changes in spastic muscle after application of BTX-A in children with cerebral palsy: Systematic review

Objective: This article aimed to review the literature to verify the effect of botulinum toxin type A (BTX-A) on the intrinsic properties of spastic muscles and functionality in children with cerebral palsy (CP). Methods: A literature search was conducted in the following databases: CINAHL, SCOPUS, Web of Science and PubMed. Database searches were limited to the period from January 1993 to March 2014. Results: A total of 2182 papers were identified, and 17 met the inclusion criteria. Only one study analyzed the effect of the toxin on muscle intrinsic properties and others analyzed the effect on functionality. Conclusion: BTX-A application demonstrated no changes in the passive stiffness of spastic muscle. In relation to functional level, the evidence of BTX-A effect was controversial. These studies showed methodological quality limitations that restrict the interpretation of the results for the entire CP population, which justifies the need for further randomized controlled trials.

Effect of botulinum toxin type A in lateral abdominal wall muscles thickness and length of patients with midline incisional hernia secondary to open abdomen management.

Abdominal wall hernia secondary to open abdomen management represents a surgical challenge. The hernia worsens due to lateral muscle retraction. Our objective was to evaluate if Botulinum Toxin Type A (BTA) application in lateral abdominal wall muscles modifies its thickness and length. A clinical trial of male trauma patients with hernia secondary to open abdomen management was performed from January 2009 to July 2011. Thickness and length of lateral abdominal muscles were measured by a basal Computed Tomography and 1 month after BTA application. A dosage of 250 units of BTA was applied at five points at each side between the external and internal oblique muscles under ultrasonographic guidance. Statistical analysis for differences between basal and after BTA application measures was performed by a paired Student's t test (significance: p<0.05). Seventeen male patients with a mean age of 35years were included. There were muscle measure modifications in all the patients. Left muscle thickness: mean reduction of 1±0.55cm (p<0.001). Right muscle thickness: mean reduction of 1.00±0.49cm (p<0.001). Left muscle length: mean increase of 2.44±1.22cm (p<0.001). Right muscle length: mean increase of 2.59±1.38cm (p<0.001). No complications secondary to BTA or recurrences at mean follow-up of 49months were observed. BTA application in lateral abdominal muscles decreases its thickness and increases its length in abdominal wall hernia patients secondary to open abdomen management.

28. Modulation of cerebral sensorimotor circuits during botulinum toxin treatment of cervical dystonia

Objective Neurophysiological and lately also functional brain imaging studies in cervical dystonia (CD) patients indicate a disorder of sensorimotor integration within extensive cortico-subcortical brain networks. Intramuscular botulinum toxin type A (BoNT-A) application has a proven clinical effect on pathological muscle activation in CD but recently has also been shown to modulate sensorimotor networks. To clarify cervical dystonia pathophysiology through functional magnetic resonance imaging of sensorimotor network changes associated with first-time botulinum toxin treatment. Methods We have studied 12 BoNT-A naive CD patients using functional MRI during specific hand motor task performance. Clinical and imaging examinations were performed before the first BoNT-A application and subsequently 4 weeks after application, at the time of maximal clinical effect of BoNT-A. Clinical treatment response was evaluated with the Tsui score, functional MRI data were analyzed with a general linear model implemented in FSL software, treatment effects were tested in pair-wise linear contrasts. Results First BoNT-A injection, although it had a good clinical effect, did not lead to any significant changes in activation of cortex or basal ganglia in our group of CD patients. Discussions Within the context of previously described sensorimotor network hypoactivation during motor task performance in CD, our observed effect of no significant change in sensorimotor cortex activation would suggest the hypothesis that robust central changes develop after long-term regular BoNT-A treatment, although even the first BoNT-A application is clinically effective. Acknowledgment Research supported by Grant IGA MH CR NT13575.