PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “FACIAL MUSCLES”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 325 records · Page 18Linked to original sources

Ephaptic transmission in hemifacial spasm: a single-fiber EMG study.

In two patients with hemifacial spasm (HFS), single-fiber EMG recordings in facial muscles demonstrated low jitter in the late responses produced by stimulation of peripheral branches to other facial muscles. Surgical decompression of the facial nerve in one patient was followed by clinical improvement and disappearance of the abnormal late responses. These observations are consistent with the hypothesis that there is ephaptic transmission among peripheral branches of the facial nerve at the site of compression in HFS.

Action Potentials↗

Familial nemaline myopathy: case reports.

Two siblings of two generations in the same family with nemaline myopathy are described. The disease affects all skeletal muscles, especially the facial muscles, producing a typical facial appearance. The diagnosis was made by light microscopy of histologically stained sections of muscle biopsy. The disease in our patients seems to be transmitted in an autosomal dominant manner. The purpose of this article is to emphasize the importance of recognition of the facial appearance by maxillofacial surgeons and the appropriate referral of patients for further neurologic examination.

Adult↗

Contralateral reinnervation of midline muscles in facial paralysis.

We report on a patient with recovery of activity of the left orbicularis oris and nasalis muscles 3 months after a complete left facial palsy. Stimulation of the affected facial nerve evoked no responses, whereas contralateral facial nerve stimulation showed polyphasic responses with very long latencies in the nasalis and orbicularis oris muscles. Needle electromyography (EMG) revealed abnormal spontaneous activity in the left orbicularis oris muscle. The motor unit action potentials on the left side of the face could be recruited only during marked contraction of the corresponding muscles on the right and were of low voltage and polyphasic ("nascent potentials"). Contralateral reinnervation is probably due to sprouting of terminal branches crossing the midline of the face and innervating bundles of muscle fibers on the affected side. This phenomenon seems unfamiliar to most clinicians. Whether the activity is due to conduction along nerve fibers or muscle fibers crossing the midline is discussed.

Adult↗

[Morphological connections between the Hypoglassal and facial nerve in the brain stem of the rat].

BACKGROUND AND OBJECTIVE: The perfect coordination and synchronization of hypoglossal and facial muscles during chewing, swallowing, breathing, and vocalization requires particular concomitant activities of the facial muscles. In contrast, no direct connection between the facial and hypoglossal nucleus on the level of the brain stem has been detected until now. PATIENTS/METHODS: Facial and hypoglossal nuclei of rats were identified on the basis of their antidromic field potential recorded after peripheral stimulation of the corresponding nerves. Stereotactically single or double fluorescence tracer injections (Biotin-Dextran, Fluorescine-Dextran, Rhodamine-Dextran, Fluoro Gold) were placed into the nuclei. RESULTS: Retrograde tracer injections into the facial nucleus consistently labeled small neurons in the hypoglossal nucleus. In reverse experiments the injection of anterograde tracers into the hypoglossal nucleus labeled fine caliber varicose nerve fibers, but no somata in the facial nucleus. Synchronous injections of different tracers into the facial and hypoglossal nucleus produced a small, but constant number of double-labeled cells in the parvocellular reticular formation. CONCLUSIONS: Both, hypoglossal interneurons projecting to the facial nucleus and neurons of the parvocellular reticular formation double-projecting to the facial and hypoglossal nucleus might play an important role in coordinated orofacial movements. Moreover, both populations of neurons might be responsible for the excellent postoperative results after hypoglossal-facial anastomosis.

Animals↗

Topical papaverine and facial nerve dysfunction in cerebellopontine angle surgery.

HYPOTHESIS: Topical application of 3% papaverine hydrochloride in the cerebellopontine angle (CPA) produces reversible conduction block of the facial nerve. BACKGROUND: A case of loss of spontaneous and evoked facial muscle activity, and transient postoperative facial paralysis, after topical application of papaverine in the CPA during surgery for an acoustic neuroma using intraoperative cranial nerve monitoring is reported. Other cases of transient neurologic dysfunction after use of this drug have been reported. METHODS: A rabbit model of CPA surgery via suboccipital craniectomy, with intraoperative monitoring of the facial nerve, was used in this experiment. RESULTS: No significant difference in facial muscle stimulation thresholds was identified after application of varying concentrations of papaverine to the facial nerve in the CPA. CONCLUSION: Although the intraoperative event described in the report is suggestive of an effect of papaverine on facial nerve function, this effect could not be reproduced in an established animal model of CPA surgery.

Action Potentials↗

Selective reinnervation of somatotopically appropriate muscles after facial nerve transection and regeneration in the neonatal rat.

The organization of the facial motor nucleus (FMN) has been examined after transection and regeneration of the facial nerve (FN) in neonatal and adult rats. In one series of experiments, horseradish peroxidase (HRP) was applied bilaterally to the superior or inferior buccal ramus 5 months after neonatal FN transection. In another series of experiments, wheat germ agglutinin-horseradish peroxidase conjugate was injected in selected vibrissae follicular muscles on both sides in animals surviving 5 months after FN transection at the neonatal or adult stage. The number and distribution of HRP-labeled cell bodies in the FMN after regeneration was compared with the contralateral side. On the uninjured side, labeled neurons were somatotopically organized. Ipsilateral to nerve injury the number of labeled cells was markedly reduced after neonatal nerve transection, but somatotopy was preserved. However, after nerve lesion at the adult stage, no significant loss of motoneurons occurred, but motor nucleus somatotopy was not maintained. Two alternative principal explanations are proposed for the re-establishment of the normal somatotopy after neonatal injury: that regenerating axons grow in a random fashion but inappropriate connections are subsequently eliminated or that regenerating axons of surviving neurons immediately follow a pathway leading to the appropriate muscle.

Aging↗

A comparative study of primary and secondary hemifacial spasm.

BACKGROUND: Hemifacial spasm (HFS) is a common movement disorder. OBJECTIVE: To evaluate possible differences in the demographic and clinical features between primary and secondary HFS. DESIGN: In-person interview using a standardized questionnaire to collect demographic and clinical data. SETTING: A multicenter study that included patients with HFS attending 3 Italian academic centers. Patients Two hundred fourteen patients with HFS. MAIN OUTCOME MEASURE: A complete neurological examination assessed the current muscle distribution of spasm and the presence of synkinetic movements between upper and lower facial muscles. RESULTS: The study sample comprised 214 patients with HFS, 81 men and 133 women, having a mean +/- SD age of 65.9 +/- 12.3 years; 164 patients were classified as having primary HFS and 50 patients (48 postparalytic and 2 symptomatic cases) were classified as having secondary HFS. Patients with primary and those with secondary HFS had similar mean +/- SD ages at onset (54.9 +/- 13.5 vs 57.0 +/- 12.8 years), male-female ratios (63:101 vs 18:32), right-sided-left-sided HFS (77:86 [1 bilateral] vs 21:28 [1 bilateral]), and frequencies of familial cases (2.9% vs 2.0%), respectively. Most patients (65.0%) with primary HFS had initial symptoms of periocular muscle contractions alone and had subsequent involvement of the lower facial muscles. Most patients (72.0%) with secondary HFS reported initial involvement of the upper and lower facial muscles simultaneously. Signs of synkinesis were present in primary (43.3%) and secondary (58.0%) HFS. CONCLUSIONS: Patients with primary and those with secondary HFS share common demographic and clinical features, including sex distribution, age at onset, affected side of HFS, synkinesis, and rarity of familial cases. Signs of synkinesis were present in significant proportions of patients with primary or secondary HFS. The 2 forms differed in clinical presentation.

Adolescent↗

Video-endoscopic facelift.

We report on our experience with 22 video-endoscopic facelift cases. We prefer the term facelift to rhytidoplasty because with the endoscopic facelift facial wrinkles are not eliminated by resecting skin but by elevating facial structures, treating the facial muscles, and improving facial contour. We treat the frontal region subperiosteally by elevating the eyebrows, minimizing wrinkles, and avoiding the coronal incision. The midthird of the face is treated subcutaneously by dissecting the skin from the SMAS, from the ear to the nasolabial fold. The endoscope is inserted through one incision and a cautery through the other. Blood vessels are cauterized. Plicating the SMAS and premalar fat pads to the temporal fascia treats the nasolabial fold and the "jowl." In the cervical region we treat the plastysma, and, with superficial liposculpture, remove excess fat and provoke skin retraction, which allows us to treat older patients who have a more flaccid skin tone. The endoscope is used to help the cauterizing and the suturing. The platysma can be sutured in the midline, if necessary. The cervical mental angle can be redefined with a Goretex 0 suture that passes from mastoid to mastoid. Modified instruments and different approaches to this technique can be expected, but we believe video endoscopy is going to have an important impact on the future of plastic surgery.

Endoscopy↗

Speed, amplitude, and asymmetry of lip movement in voluntary puckering and blowing expressions: implications for facial assessment.

The context of voluntary movement during facial assessment has significant effects on the activity of facial muscles. Using automated facial analysis, we found that healthy subjects instructed to blow produced lip movements that were longer in duration and larger in amplitude than when subjects were instructed to pucker. We also determined that lip movement for puckering expressions was more asymmetric than lip movement in blowing. Differences in characteristics of lip movement were noted using facial movement analysis and were associated with the context of the movement. The impact of the instructions given for voluntary movement on the characteristics of facial movement might have important implications for assessing the capabilities and deficits of movement control in individuals with facial movement disorders. If results generalize to the clinical context, assessment of generally focused voluntary facial expressions might inadequately demonstrate the full range of facial movement capability of an individual patient.

Adult↗

Electrophysiological investigations in a case of cephalic tetanus.

In a case of cephalic tetanus the amplitudes and the latencies of the compound action potentials recorded from the facial muscles after stimulation of the facial nerve at the mastoid were not significantly different on the two sides. With repetitive stimulation at 30/sec a pathological facilitation was observed on both sides. The blink reflex bilaterally had normal latencies but the amplitudes of the reflex potentials were always significantly lower on the paretic side. It is concluded that facial palsy in cephalic tetanus is mainly due to a functional block of conduction in the course of the peripheral nerve whereas the disturbance of neuromuscular transmission probably has little importance in these cases.

Action Potentials↗

Related timing for peripheral and central plasticity in hypoglossal-facial nerve anastomosis.

The aim of this work was to determine the role of peripheral facial muscle reinnervation in the central reorganization of the blink reflex (BR) after hypoglossal-facial anastomosis (HFA). An electrophysiological study was performed on seven patients who underwent HFA after facial nerve transection during surgery for acoustic neuroma. HFA was performed within 15 days after surgery in five patients (group 1) and later for the two others (group 2). We studied the motor responses (MR) and the BR evoked on the affected side, before and over 3 years after the HFA. The MR appeared by the third month for the first group, and by the sixth and twelfth for the second group. After 36 months, the amplitude of MR was significantly higher than its control value, showing hyperinnervation of the facial muscles. Study of the BR evoked only an R1-type blink response that was observed 4 and 6 months after the MR for groups 1 and 2, respectively. This central reorganization appeared closely correlated with muscle reinnervation and its related timing. The occurrence of peripheral nerve-muscle contacts seems to be a necessary condition for reorganization of the trigemino-hypoglossal-facial reflex.

Adult↗

[Mime functional evaluation in facial paralysis following a stroke].

BACKGROUND: Functional evaluation of the facial movements in patients with facial paralysis following a stroke. AIM: To evaluate the function of the facial muscles of patients after central facial paralysis following a stroke. METHOD: Nine patients referred by the Neurology Service were evaluated. The evaluation focused on spontaneous, voluntary and reflex movements. RESULTS: Reflex and voluntary movement of the eyelid and forehead were preserved in all patients. However, spontaneous and voluntary movements of the lips and nose were limited according to the location and extension of lesion. CONCLUSION: The symptoms of central facial paralysis, in which paralysis only of voluntary movements of the lower two-thirds of the face is expected, occurred in the minority of the patients.

Adult↗

Functional mapping of the motor cortex of the white mouse by a microstimulation method.

Studies on 33 anesthetized white mice were used to determine the motor representation of facial muscles and limb muscles by an intracortical microstimulation method. Microstimulation produced predominantly ipsilateral movement responses of facial muscles and contralateral responses in fore- and hindlimb muscles. Low-threshold stimulation in the left and right hemispheres showed a clear asymmetry of the motor representation of the facial muscles. Movement responses of the hindlimbs were obtained on microstimulation of the frontal regions of the neocortex, demonstrating the existence of multiple motor representations of muscles in the neocortex.

Animals↗

Management of facial spasm with Clostridium botulinum toxin, type A (Oculinum)

One hundred five patients received 391 graded injections of Clostridium botulinum type A toxin (Oculinum) to treat uncontrollable facial muscle spasm. Patients had essential blepharospasm (n = 61), hemifacial spasm (n = 24), or aberrant regeneration of the seventh cranial nerve (n = 20). Muscle spasms were reduced within two days of the first injection of toxin and, in most cases, the drug effect lasted three to four months. Control of facial muscle spasm was achieved in all patients. Complications related to treatment included transient blepharoptosis (n = 7), diplopia (n = 2), and altered facial expression (n = 11). Systemic side effects were not observed. Select chemodenervation of facial muscles with graded injections of botulinum toxin is a useful adjunct to control blepharospasm, hemifacial spasm, and facial spasm due to aberrant regeneration of the facial nerve.

Blepharoptosis↗

Changes in oral functions and muscular behavior due to surgical orthodontic treatment.

The faces of fifteen adult patients who had undergone surgical orthodontic treatment were videotaped frontally and laterally in order to observe their oral circumferential behavior for function and their facial muscle posture at rest. As the ANB angle became 0.9 degrees from -3.5 degrees and the occlusal relationship improved to normal, facial morphology became harmoneous. In general observation, habits of facial muscle tensity at rest was reduced and lip sucking following forward tongue thrusting was decreased after treatment. Pronunciation of previously unclear sounds such as 'Ta' and 'Sa' improved and breath leakage decreased after treatment. The cooperative motions between lips and tongue improved significantly. Although a few subjects still had weak lip tensity and facial muscles, habits of tongue thrusting during swallowing were generally reduced and swallowing motions became more natural. As the movement of tongue tip became smoother, rhythmical chewing improved, and they became capable of chewing on both sides. Good relationships between morphology, oral function, and muscular behavior are very important in stabilization of the normal dentition after surgical orthodontic treatment. Normally maintained forces of balanced occlusion reduce the possibility of relapse.

Adult↗