Facial Muscles (facial + muscle)

Distribution by Scientific Domains


Selected Abstracts


Decreased Tear Expression with an Abnormal Schirmer's Test Following Botulinum Toxin Type A for the Treatment of Lateral Canthal Rhytides

DERMATOLOGIC SURGERY, Issue 2 2002
Seth L. Matarasso MD
background. Inactivation of muscles of facial expression by chemodenervation with botulinum toxin remains an off-label indication. Nevertheless, it continues to be a safe and effective technique to improve dynamic rhytides and is the treatment of choice for the hypertrophic lateral fibers of the orbicularis oculi muscle that can cause the superimposed crow's feet. objective. Although infrequent and self-limiting, the complication of unexpected muscle weakness from toxin diffusion or erroneous placement is documented. methods. However, injection into the pretarsal portion of the orbicularis oculi muscle resulting in unilateral ocular irritation and diminished tear expression as evidenced by a dry eye and an abnormal Schirmer's test has rarely been reported. Direct injection into the pretarsal fibers of the muscle as opposed to diffusion of the toxin into the muscle fibers or the lacrimal gland was consistent with the onset of action of the toxin and the prolonged duration of the ocular symptoms. results. Treatment consisted of ocular lubrication until the effects of the toxin dissipated and muscle tone returned. Subsequent treatment did not result in a result in a recurrence of adverse sequelae. conclusions. Facial muscles are small, not isolated, and often have fibers that interdigitate. An important factor in the administration of botulinum toxin is the identification of the muscles responsible for the corresponding rhytide. Precise knowledge of muscular anatomy and function will aid in minimizing this and other potential complications. [source]


Changes in a rat facial muscle after facial nerve injury and repair

MUSCLE AND NERVE, Issue 9 2001
Davor Jergovi
Abstract This study describes changes in a rat facial muscle innervated by the mandibular and buccal facial nerve branches 4 months after nerve injury and repair. The following groups were studied: (A) normal controls; (B) spontaneous reinnervation by collateral or terminal sprouting; (C) reinnervation after surgical repair of the mandibular branch; and (D) chronic denervation. The normal muscle contained 1200 exclusively fast fibers, mainly myosin heavy chain (MyHC) IIB fibers. In group B, fiber number and fiber type proportions were normal. In group C, fiber number was subnormal. Diameters and proportions of MyHC IIA and hybrid fibers were above normal. The proportion of MyHC IIB fibers was subnormal. Immediate and delayed repair gave similar results with respect to the parameters examined. Group D rats underwent severe atrophic and degenerative changes. Hybrid fibers prevailed. These data suggest that spontaneous regeneration of the rat facial nerve is superior to regeneration after surgical repair and that immediacy does not give better results than moderate delay with respect to surgical repair. Long delays are shown to be detrimental. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1202,1212, 2001 [source]


Functional reconstruction of the lateral face after ablative tumor resection: Use of free muscle and musculocutaneous flaps

HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 10 2001
Tugrul Maral MD
Abstract Background Wide resection of tumors of the middle third of the face often results in complex three-dimensional defects and facial paralysis either due to removal of the facial nerve within the tumoral tissue or to extensive resection of the facial muscles. Methods We report the cases of three patients who underwent wide excision of tumors of the cheek region, operations that resulted in tissue defects and facial palsy. Defect reconstruction and facial reanimation was accomplished in one stage through functional muscle transplantation. Results Follow-up of more than 1 year showed good symmetry at rest and reanimation of the corner of the mouth in all cases, but one patient, in which the ipsilateral facial main trunk was used as motor nerve supply to the transplanted muscle, developed significant muscle contracture and binding of the cheek skin. Conclusions Every effort should be made to optimize the functional and cosmetic outcomes of neurovascular muscle transfers through precise planning and careful execution of the intricate details of the surgical technique for muscle transplantation. © 2001 John Wiley & Sons, Inc. Head Neck 23: 836,843, 2001. [source]


Characterisation of human soft palate muscles with respect to fibre types, myosins and capillary supply

JOURNAL OF ANATOMY, Issue 2 2000
PER S. STÅL
Four human soft palate muscles, and palatopharyngeus, the uvula, the levator and tensor veli palatini were examined using enzyme-histochemical, immunohistochemical and biochemical methods and compared with human limb and facial muscles. Our results showed that each palate muscle had a distinct morphological identity and that they generally shared more similarities with facial than limb muscles. The palatopharyngeus and uvula muscles contained 2 of the highest proportions of type II fibres ever reported for human muscles. In contrast, the levator and tensor veli palatini muscles contained predominantly type I fibres. A fetal myosin heavy chain isoform (MyHC), not usually found in normal adult limb muscles, was present in a small number of fibres in all palate muscles. The mean muscle fibre diameter was smaller than in limb muscles and the individual and intramuscular variability in diameter and shape was considerable. All palate muscles had a high capillary density and an unusually high mitochondrial enzyme activity in the type II fibres, in comparison with limb muscles. No ordinary muscle spindles were observed. The fibre type and MyHC composition indicate that the palatopharyngeus and uvula muscles are functionally involved in quick movements whereas the levator and tensor veli palatini muscles perform slower and more continuous contractions. The high aerobic capacity and the rich capillarisation suggest that the palate muscles are relatively fatigue resistant. Absence of ordinary muscle spindles indicates a special proprioceptive control system. The special morphology of the palate muscles may be partly related to the unique anatomy with only one skeletal insertion, a feature consistent with muscle work at low load and tension and which may influence the cytoarchitecture of these muscles. Other important factors determining the special morphological characteristics might be specific functional requirements, distinct embryological origin and phylogenetic factors. [source]


Current opportunities and challenges in skeletal muscle tissue engineering

JOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 6 2009
Merel Koning
Abstract The purpose of this article is to give a concise review of the current state of the art in tissue engineering (TE) of skeletal muscle and the opportunities and challenges for future clinical applicability. The endogenous progenitor cells of skeletal muscle, i.e. satellite cells, show a high proneness to muscular differentiation, in particular exhibiting the same characteristics and function as its donor muscle. This suggests that it is important to use an appropriate progenitor cell, especially in TE facial muscles, which have a exceptional anatomical and fibre composition compared to other skeletal muscle. Muscle TE requires an instructive scaffold for structural support and to regulate the proliferation and differentiation of muscle progenitor cells. Current literature suggests that optimal scaffolding could comprise of a fibrin gel and cultured monolayers of muscle satellite cells obtained through the cell sheet technique. Tissue-engineered muscle constructs require an adequate connection to the vascular system for efficient transport of oxygen, carbon dioxide, nutrients and waste products. Finally, functional and clinically applicable muscle constructs depend on adequate neuromuscular junctions with neural cells. To reach this, it seems important to apply optimal electrical, chemotropic and mechanical stimulation during engineering and discover other factors that influence its formation. Thus, in addition to approaches for myogenesis, we discuss the current status of strategies for angiogenesis and neurogenesis of TE muscle constructs and the significance for future clinical use. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Bilateral pallidal stimulation for idiopathic segmental axial dystonia advanced from meige syndrome refractory to bilateral thalamotomy,

MOVEMENT DISORDERS, Issue 4 2001
Daisuke Muta MD
Meige syndrome is an adult-onset dystonic movement disorder that predominantly involves facial muscles, while some patients with this syndrome develop spasmodic dysphonia and dystonia of the neck, trunk, arms, and legs. We report that all dystonic symptoms that had been refractory to both pharmacotherapy and bilateral thalamotomy were markedly alleviated by bilateral pallidal stimulation in a patient with segmental axial dystonia advanced from Meige syndrome. © 2001 Movement Disorder Society. [source]


Electrodiagnostic studies of the facial nerve in peripheral facial palsy and hemifacial spasm,

MUSCLE AND NERVE, Issue 1 2007
Josep Valls-Solé MD
Abstract Electrodiagnostic (EDX) assessment is one of the most important aspects in the evaluation of the two most common disorders of the facial nerve: facial palsy and hemifacial spasm. Facial palsy is usually an acute disorder that resolves in a few weeks but, in a number of cases, leads to a postparalytic facial syndrome featuring muscle synkinesis, myokymia, and involuntary mass contractions of muscles on the affected side. Hemifacial spasm is usually a chronic disorder characterized by paroxysms of involuntary, clonic, and synchronous twitching of all facial muscles on the affected side. EDX studies provide information on lesion location and severity, pathophysiology underlying the two disorders, and differential diagnosis between syndromes presenting with abnormal facial muscle activity. This monograph is intended to describe the most relevant EDX findings in the two disorders and the most appropriate timing for the examinations in order to provide useful information for prognosis and therapeutic decision-making. Muscle Nerve, 2007 [source]


Single-fiber electromyography in limb and facial muscles in muscle-specific kinase antibody and acetylcholine receptor antibody myasthenia gravis,

MUSCLE AND NERVE, Issue 4 2006
Maria Elena Farrugia DPhil
Abstract We examined the findings from single-fiber electromyography in extensor digitorum communis (EDC) and orbicularis oculi (OOc) in 13 myasthenia gravis (MG) patients with muscle-specific kinase antibodies (MuSK-MG) and 12 MG patients with acetylcholine receptor antibodies (AChR-MG) with similar clinical scores. More than 70% of AChR-MG patients had abnormal jitter in both EDC and OOc, but the majority of MuSK-MG patients had normal jitter in EDC despite abnormal jitter in OOc. These findings demonstrate clear differences between the neurophysiology of MuSK-MG and AChR-MG. Muscle Nerve, 2005 [source]


Lateral spread response elicited by double stimulation in patients with hemifacial spasm

MUSCLE AND NERVE, Issue 6 2002
Shinya Yamashita MD
Abstract In patients with hemifacial spasm (HFS), a lateral spread response (or abnormal muscle response) is recorded from facial muscles after facial nerve stimulation. The origin of this response is not completely understood. We studied the lateral spread responses elicited by double stimulation in 12 patients with HFS during microvascular decompression. The response was recorded from the mentalis muscle by electrical stimulation of the temporal branch of the facial nerve or from the orbicularis oculi muscles by stimulation of the marginal mandibular branch. The interstimulus intervals (ISIs) of double stimulation ranged from 0.5 to 7.0 ms. R1 was defined as the response elicited by the first stimulus, and R2 as the response elicited by the second stimulus. R1 had a constant latency and amplitude regardless of the ISI, whereas R2 appeared after a fixed refractory period without facilitation or depression in a recovery curve of latency and amplitude. From these findings, we consider that the lateral spread response is due to cross-transmission of facial nerve fibers at the site of vascular compression rather than arising from facial nerve motor neurons. © 2002 Wiley Periodicals, Inc. Muscle Nerve 25: 000,000, 2002 [source]


Pericranial muscular, respiratory, and heart rate components of the orienting response

PSYCHOPHYSIOLOGY, Issue 6 2002
J.J. Stekelenburg
We have earlier found that voluntary attention to weak auditory stimuli induces inhibition of respiration, heart rate, and electromyographic (EMG) activity of masticatory and lower facial muscles and that these responses lower the auditory threshold for low-frequency sounds. In the current study, we examined whether this inhibitory response pattern also occurs during involuntary orienting to novel, nonsignal sounds. Environmental sounds of low intensity were presented unexpectedly during the performance of a reading task. Orienting responses (ORs) were elicited as indicated by heart rate deceleration and skin conductance responses. Inhibitory respiratory and pericranial EMG responses appeared to be intrinsic components of the OR. Together with the autonomic responses, they habituated when a nonsignal auditory stimulus was repeatedly presented. Our results also suggest that eye and pinna movements occurred toward the sound source. The results of the current study are consistent with the hypothesis of Sokolov (1963) that the primary function of the OR is enhancement of sensory sensitivity. [source]