Nasal Muscle Research Articles

Transection of the Nasal Base Muscles for the Correction of Plunging Tip: An Outcome Analysis.

The plunging-tip deformity has been attributed to the combined actions of nasal base muscles. However, there are no quantitative data in the literature to discuss the effect of muscle transections on the clinical outcome. This study was designed to assess the actions of the nasal tip, nasal base, and upper lip in patients with plunging-tip deformity and to compare their preoperative and postoperative activities following multiple myotomies. Patients were treated for nasal base animation deformity by the transection of the depressor septi nasalis, myrtiformis, nasalis, and levator labii superior alaeque nasi muscles. The profile views of preoperative and 12 months postoperative photographs were selected for measurements. Rest and smile images were overlaid to achieve alignment, and movements were measured with reference to the Frankfurt horizontal plane. Twenty-seven (27) patients were included in the study. Movements of the nasal tip and nasal base were significantly reduced postoperatively. The upper lip shortened significantly in smile poses postoperatively compared with preoperative measurements. The change in the tip angle during animation significantly decreased in the postoperative measurements. Movements of the nasal tip and the alar base contributed significantly to the hyperdynamic nasal tip deformity. Transection of the nasal base muscles is an effective treatment method with a weaker recovery of the muscle function in the long term. Dynamic upper lip shortening is an unexpected finding following surgery and should be investigated further.

S12-1. Diagnostic sensitivity and specificity of the laboratory tests in myasthenia gravis

The diagnostic sensitivity of repetitive nerve stimulation (RNS) in patients with myasthenia gravis (MG) varies as the choice of muscles studied and method used as “gold standard” to judge sensitivity and specificity. Many research in MG-RNS studies for more high sensitivity were reported previously, almost generalized MG RNS sensitivity was from 60% to 80% slight more sensitive than serological study. We recommend RNS examination of at least 3 muscles, nasalis, trapezius, and deltoid. Sensitivity of RNS in generalized seropositive MG were 54%, 51%, 62%. The seronegativity of AChR frequency reported subsequently has ranged from 7% to 40% for all acquired MG patients, and from 6% to 30% for generalized MG. We hope RNS and SFEMG for diagnosis of MG could help to pick up from seronegative patients. SFEMG is one of the key, and combination of selection of examination for RNS is another key of diagnosis for MG. Pitfall of specificity of RNS is misdiagnosis of motor neuron disease decrement as same as neuromuscular transmission dysfunction. We should be aware of sensitivity of RNS for ALS is higher than MG except nasalis muscle.

Occipitalis muscle: using for repetitive facial nerve stimulation in myasthenia gravis

Repetitive nerve stimulation (RNS) is a highly sensitive electrophysiological test used for diagnosing myasthenia gravis (MG). Here, we evaluated electrodiagnostic value of RNS using facial nerve and occipitalis muscle. Patients with generalized MG were included. Clinical findings were assessed. RNS test was performed on occipitalis, nasalis, trapezius, abductor policis brevis (APB) and abductor digiti minimi (ADM) muscles. Twenty-five (78%) patients had relevant decrement during RNS test of at least one muscle. Nasalis muscle had the highest diagnostic potential (68.8%), followed by trapezius (53.3%), occipitalis (50%), APB (30%) and ADM (16.7%) muscles. There was not a significant relationship between clinical symptoms and facial RNS recorded on occipitalis muscle. In conclusion, we suggest that facial RNS recording over occipitalis muscle can be added in electrodiagnosis of MG because of cranial nerve innervation and proximal location. Facial RNS recording over occipitalis muscle provides a good choice under the conditions such as atrophy, cosmetic surgery, or botulinum toxin application in which nasalis muscle is unavailable for use.

Non-auditory, electrophysiological potentials preceding dolphin biosonar click production

The auditory brainstem response to a dolphin’s own emitted biosonar click can be measured by averaging epochs of the instantaneous electroencephalogram (EEG) that are time-locked to the emitted click. In this study, averaged EEGs were measured using surface electrodes placed on the head in six different configurations while dolphins performed an echolocation task. Simultaneously, biosonar click emissions were measured using contact hydrophones on the melon and a hydrophone in the farfield. The averaged EEGs revealed an electrophysiological potential (the pre-auditory wave, PAW) that preceded the production of each biosonar click. The largest PAW amplitudes occurred with the non-inverting electrode just right of the midline—the apparent side of biosonar click generation—and posterior of the blowhole. Although the source of the PAW is unknown, the temporal and spatial properties rule out an auditory source. The PAW may be a neural or myogenic potential associated with click production; however, it is not known if muscles within the dolphin nasal system can be actuated at the high rates reported for dolphin click production, or if sufficiently coordinated and fast motor endplates of nasal muscles exist to produce a PAW detectable with surface electrodes.

Myastenia gravis s protilátkami proti MuSK

Myastenia gravis je autoimunitni onemocněni s tvorbou protilatek proti postsynapticke casti nervosvalove plotenky. Při průkazu protilatek proti acetylcholinovým receptorům se jedna o seropozitivni myastenia gravis a pokud tyto protilatky nejsou přitomny, pak je to seronegativni myastenia gravis. U 35 % (0–49 %) seronegativnich forem byla prokazana protilatka proti svalove specificke tyrozin-kinaze (MuSK). Tyto anti-MuSK myasthenia gravis se vyznacuji převahou postiženi žen, casnějsich vznikem, charakteristickým klinickým nalezem, horsi a nekonstantni reakci na lecbu inhibitory cholinesterazy. Z neurofyziologických vysetřeni je důležite vysetřit repetitivni stimulaci i proximalni svaly (m. trapezius, m. deltoides) a mimicke svaly (m. nasalis, m. orbicularis oculi). Při vysetřeni SF EMG (single-fiber EMG) je podstatně vyssi pozitivita při vysetřeni m. frontalis ci m. orbicularis oculi. Neni indikovana thymektomie. Ucinna je imunoterapie – podani imunoglobulinů, plazmafereza, kortikoidy v kombinaci s dalsimi imunosupresivy. Myastenia gravis s anti-MuSK protilatkami se vyznacuje nestabilnim průběhem, větsi frekvenci myastenických krizi a větsi terapeutickou narocnosti.

Anatomical Study and Comprehensive Review of the Incisivus Labii Superioris Muscle: Application to Lip and Cosmetic Surgery.

ObjectivesThe incisivus labii superioris muscle, which originates from the floor of the incisive fossa of the maxilla, has previously been described, it is not well understood. The purpose of this study was to investigate the incisivus labii superioris muscle with detailed dissection.MethodsTwenty-six halves from thirteen fresh frozen cadaveric Caucasian heads were used in this study. First, the incisivus labii superioris muscle was dissected to reveal its origin and insertion, and its relationship to other mimetic muscles. Secondly, the distance from the midline to the innermost part of the bony attachment of the muscle was measured. The literature describing the incisivus labii superioris muscle was reviewed.ResultsThe incisivus labii superioris muscle consisted of two parts, inferior and superior. The former merged into the orbicularis oris and the latter into the nasalis. The mean distance from the midline to the innermost part of the bony attachment of the incisivus labii superioris muscle was 4.8 ± 1.7 mm on the right side and 4.9 ±1.7 mm on the left.ConclusionsThe results of the present study suggest that the inferior part of the incisivus labii superioris should be considered as an accessory muscle of the orbicularis oris complex, and the superior part is the nasalis muscle.

Repetitive Facial Nerve Stimulation Using Occipitalis Muscle.

We aimed to evaluate the reliability and reproducibility of repetitive nerve stimulation recorded on occipitalis muscle by comparing recordings on nasalis muscle in healthy subjects. A total of 23 healthy subjects (mean age: 44.7 ± 13.8 years) underwent detailed neurological examination and repetitive nerve stimulation using nasalis and occipitalis muscles. Amplitude and area percentage changes of compound muscle action potentials (CMAPs) after repetitive nerve stimulation with different frequency were compared between right and left sides and between recordings on nasalis and occipitalis muscles. Comparisons of percentage amplitude changes of nasalis and occipitalis CMAPs showed no differences (+0.1% ± 3.8% vs. +1.4% ± 3.9%, P = 0.129). Average area percentage change of nasalis CMAPs was 0.3% ± 19.0%, whereas the value of occipitalis CMAP was +2.8% ± 15.2% (P = 0.851). Comparisons of nasalis and occipitalis CMAPs values showed no differences. The repetitive nerve stimulation recorded on occipitalis muscle is simple, easy to apply, noninvasive, consistent, and reproducible.

Functional repair of cleft lip: from anatomical resetting to biomechanical simulation

We are no longer entangled in the anatomical resetting of the labial-nasal muscle itself, but the sight to the muscle fiber level, to study the relationship between the muscle fiber force line and the labial-nasal shape. In the past ten years, we focused on the lip of nasal muscle fiber anatomy, imageology and biomechanics, carried out a series of research works, realized the three-dimensional (3D) visualization of small labial-nasal muscle fiber, established configuration models of normal and cleft lip with nasal muscle fibers, and put forward the hypothesis of naso-labial muscle tension band. According to the biomechanical parameters of lip nasal muscle, cartilage, skin and subcutaneous tissue, we initially established a biomechanical model elaborating the relationship between labial-nasal muscle tension lines and surface morphology; we summed up three muscle tension group which determines labial-nasal contour, explained the biomechanical mechanism in cleft lip and various lip nasal deformities, and realized the possibility to freely change the 3D labial-nasal contour by lip nasal lip nasal muscle tension theory; Finally we carried out clinical validation in clinical treatment of cleft lip, achieved the effect of detail cleft lip repairing.

Anatomical relationships of the procerus with the nasal ala and the nasal muscles: transverse part of the nasalis and levator labii superioris alaeque nasi.

The aim of this study was to clarify the anatomical relationship of the procerus with the nose, especially focusing on the transverse part of the nasalis, the nasal ala, and the levator labii superioris alaeque nasi (LLSAN). The 53 faces from Korean cadavers were examined anatomically. The procerus originated from the superficial and deep layers in all specimens. Some fibers of the lateral part of the superficial layer extended to connect to the transverse part of the nasalis, while other such fibers extended to attach to the skin of the upper nasal ala in all specimens. The superficial and deep layers of the procerus merged and then intermingled with the frontalis. The anatomical relationship between the superficial layer of the procerus and the LLSAN was classified into the following two categories according to their connections. Some medial originating fibers of the LLSAN extended superomedially to blend in the area between the superficial layer of the procerus and the depressor supercilii (13.5%). And, some medial originating fibers of the LLSAN extended superomedially and then constituted the lateral portion of the superficial layer of the procerus (7.7%). This study has yielded crucial data for understanding the anatomical relationships and functions of the procerus in relation to the nose. They will be helpful when designing effective therapies involving botulinum toxin type A, performing various types of rhinoplasty and facial surgeries, and in electromyography analyses.

Pathologic anatomy of the soft palate, part 1: Embryology, the hard tissue platform, and evolution

The purpose of this communication is to explore in detail the developmental anatomy of the soft palate, its pathologies, and strategies for management. Despite the voluminous literature regarding complete cleft palate in its usual presentation, little attention has been paid to the biology of the isolated soft palate cleft. It exists as a spectrum, ranging in severity from the submucous variant, with nothing notable save a groove and a palpable defect of the posterior spine, all the way to a complete disruption of the soft tissue envelope and the horizontal palatine shelves. All these presentations are but variations of common pathology. Much can be gained from a disciplined examination of these. Our discussion includes two parts. The first part is on the embryologic events that generate the mesenchymal building blocks from which the posterior palate is constructed: palatine bone, oral and nasal mucosa, palatine aponeurosis, and muscle slings. Palate structures develop from neural crest and mesoderm; these tissues originate at specific sites along the axis of the embryo and they can be mapped according to the developmental units of the central nervous system (CNS) from which they are innervated. These units, called neuromeres, are specific zones within the neural tube, the boundaries of which are established by the expression pattern of homeotic genes. The forebrain (prosencephalon) has telencephalon and 3 prosomeres, the midbrain (mesencephalon) has 1-2 mesomeres, and the hindbrain (rhombencephalon) has 12 rhombomeres. Each neuromere has a specific neuroanatomic content and is hardwired to specific tissues outside the brain. We next consider a model of the palate which is analogous to a pinball machine that consists of a platform (bone) and mobile “flippers” or lever arms (the velum). In this study, the osseous platform is discussed in detail with neural crest bones being coded by the sensory innervation of their surrounding soft-tissue envelope. Maxilla, palatine bone, and vomers are all derivatives of hindbrain neural crest arising from rhombomere 2 but distributed according to various neurovascular pedicles of the V2 stapedial system, the anatomy of which will be explained in detail. Next, the evolution of palate will be presented as a series of innovations favoring increased metabolic capacity. A final appendix presents a functional classification of cranial nerves which I have endeavored to make straightforward. This will prove useful when reading the second part of this manuscript having to do with the neuromuscular apparatus of the soft palate.

Facing the Worst Risk: Confronting the Dorsal Nasal Artery, Implication for Non-surgical Procedures of Nasal Augmentation.

The nose is a dangerous site for filler injection. This study investigated the anatomy of the dorsal nasal artery at the upper part of the nose to clarify how ocular complications occur. Dissections were performed in 50 noses of the embalmed cadavers. Either the soft embalming or formaldehyde embalming processes were used. The dorsal nasal artery is not a constant artery. The artery traveled in the subcutaneous tissue layer of the nasal dorsum on the transverse nasalis muscle and its midline nasal aponeurosis which connected the muscles on both sides. Bilateral dorsal nasal arteries existed only in 34%. In 28% of the specimens, a single and large dorsal nasal artery was presented. The diameter was 0.4 ± 0.2mm when bilateral dorsal nasal arteries were present and 0.7 ± 0.3mm in a single artery. The largest artery was 1.2mm. The artery usually crossed the midline at the middle third part of the nose over the upper lateral cartilages to form an anastomosis with the contralateral lateral nasal artery as the oblique nasal artery in 14%. The artery might descend and communicate with the ipsilateral lateral nasal artery in 6% or descended as a midline artery and form the nasal tip plexus in 8%. In 38% of the specimens, the arteries became small, formed a subcutaneous plexus and randomly distributed on the superficial layer of the subcutaneous tissue in the upper two-thirds of the nose. During the injections at the upper (bony) and middle (cartilaginous) part of the nose for nasal dorsal augmentation, the injector has to make sure the cannula tip is in the preperiosteal plane by reinsertion of the cannula if needed, due to the chance of encountering the large single dorsal nasal artery at the midline. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

The effect of a Le Fort I incision on nose and upper lip dynamics: Unraveling the mystery of the "Le Fort I lip".

Postoperative flattening of the upper lip with loss of lip pout and down turning of the corners of the mouth is often seen after Le Fort I surgery. We aim to determine which facial muscles are involved in this phenomenon to update the literature on this subject. In 6 cadavers, a unilateral Le Fort I incision was executed. After removal of the skin, all individual facial muscles were identified and submitted to bilateral tactile traction, comparing incised sides with non-incised sides. All the components of the deep layer of the modiolus alae nasi (transverse part of the nasalis muscle and the myrtiformis muscle) and the deep layer of the midface musculature (levator anguli oris muscle) were transected by the Le Fort I incision. After performing the incision, the majority of the depressor septi nasi is intact. Further, the superficial layer of the midface musculature is intact but it loses tension because of its connection to the deep layer. This study suggests the importance of correctly suturing the deep muscular layers to maintain the 3-dimensional facial contour. Moreover, in this cadaver study, we attempt to predict the functional consequences on the impairment of facial mimics related to the Le Fort I incision.

Motor unit number index in the nasalis muscle in healthy subjects and patients with amyotrophic lateral sclerosis.

Motor unit number index (MUNIX) is a quick and feasible electrophysiological technique that estimates the number of motor neurons in limb muscles in healthy and amyotrophic lateral sclerosis (ALS) subjects. In this study we explored the feasibility, reliability, and differences of MUNIX in nasalis muscles in healthy subjects and ALS patients. MUNIX of the nasalis muscle of 50 healthy and 20 ALS subjects with bulbar involvement was compared. Functional impairment was evaluated by the ALS Functional Rating Scale-Revised and its bulbar subscore. MUNIX was well tolerated and quickly performed. Bulbar ALS patients showed non-significant lower nasalis MUNIX values and a lower functional bulbar subscore. Intra- and interrater reliability showed high intraclass correlation coefficients (ICCs) in healthy subjects (0.87) and ALS patients (0.92). MUNIX of the nasalis muscle is a reproducible method, but it showed no significant difference between healthy and bulbar ALS subjects and seems not to be a useful marker of disease progression in ALS. Muscle Nerve 54: 733-737, 2016.

Electrophysiologic Evaluation of the Facial Nerve and Blink Reflex Pathways in Asymptomatic Cochlear Implant Users.

To evaluate the functional integrity of the facial nerve and blink reflex (BR) pathways in asymptomatic patients who underwent cochlear implantation (CI). Case series with planned data collection. Tertiary referral center. Twenty-four deafened patients with unilateral CI who had no complications were enrolled. Bilateral compound muscle action potentials (CMAPs) of the facial nerve were recorded over the nasalis and occipitalis muscles, whereas BR responses were recorded over the orbicularis oculi after supraorbital nerve stimulation. All recordings were performed when the external part of the implant was in place (CIp) and after its removal (CIr), except occipitalis recordings, which were performed only after removal. The amplitude and latency of CMAP were measured to evaluate the axonal integrity of the zygomatic and posterior branches of the facial nerve. Latency, amplitude, and duration of the BR were measured to investigate the integrity of trigeminofacial connections. The amplitude and latency of CMAP over the nasalis muscle were bilaterally normal, and the difference between CIp and CIr was not statistically significant. No CMAP of the occipitalis muscle was recorded in 4 (16.7%) patients, and low-amplitude responses were recorded on the implant side of 20 (83.3%). Amplitudes of the contralateral R2 response were higher in the CIp condition versus the CIr condition (P = .031). There were no differences among other BR components. During functioning of the CI system, excitability of the facial circuit may increase either through the facial motor nucleus or through removal of the inhibitory effect of the descending pathway.

A Predictable Approach for Osteotomy in Rhinoplasty: A New Concept of Open External Osteotomy.

Summary:Nasal osteotomies are a cornerstone step for closing an open roof deformity after dorsal hump surgery. Notwithstanding, the optimal method of nasal osteotomy remains controversial, as evidenced by the variety of approaches with no consensus between authors. Moreover, the election of the technique responds to surgeon’s preference. We proposed a new way to perform both medial and lateral osteotomies under direct vision. Direct vision of nasal osteotomies provides more predictable control and precision than blind procedures, making this procedure more reliable and easier for both novel and experienced surgeons. Other advantages include conservation of nasal muscle, angular vasculature, and periosteum, which allow less postoperative ecchymosis and edema and less risk of synechia and lacrimal sac injury.

Safe Planes for Injection Rhinoplasty: A Histological Analysis of Midline Longitudinal Sections of the Asian Nose.

Dorsal nasal augmentation is an essential part of injection rhinoplasty on the Asian nose. Aesthetic physicians require detailed knowledge of the nasal anatomy to accurately and safely inject filler. One hundred and thirty-five histological cross sections were examined from 45 longitudinal strips of soft tissue harvested from the midline of the nose, beginning from the glabella to the nasal tip. Muscles and nasal cartilage were used as landmarks for vascular identification. At the nasal tip, a midline longitudinal columellar artery with a diameter of 0.21 ± 0.09 mm was noted in 14 cadavers (31.1 %). At the infratip, subcutaneous tissue contained cavernous tissue similar to that of the nasal mucosa. The feeding arteries of these dilated veins formed arteriovenous shunts, into which retrograde injection of filler may be possible. All of the nasal arteries present were identified as subcutaneous arteries. They coursed mainly in the superficial layer of the subcutaneous tissues, with smaller branches forming subdermal plexuses. A substantial arterial anastomosis occurred at the supratip region, in which the artery lay in the middle of the subcutaneous tissue at the level of the major alar cartilages. These arteries had a diameter ranging between 0.4 and 0.9 mm and were found in 29 of 45 specimens (64.4 %). This was at the level midway between the rhinion above the supratip and the infratip. This anastomotic artery also crossed the midline at the rhinion superficial to the origin of the procerus on the lower end of the nasal bone. Here the arterial diameter ranged between 0.1 and 0.3 mm, which was not large enough to cause arterial emboli. Fascicular cross sections of the nasalis muscle directly covered the entire upper lateral cartilage. The subdermal tissue contained few layers of fat cells along with the occasional small artery. The procerus arose from the nasal bone and was continuous with the nasalis in 16 cadavers (35.6 %). There was fatty areolar tissue between the procerus and the periosteal layer and no significant arteries present. The procerus ascended beyond the brow to insert into the frontalis muscle with very few cutaneous insertions. The supratrochlear vessels and accompanying nerve were occasionally found on the surface of the frontalis muscle. Most nasal arteries found in the midline are subcutaneous arteries. Filler should be injected deeply to avoid vascular injury leading to compromised perfusion at the dorsum or filler emboli at the nasal tip. This journal requires that the authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Detailed Anatomy of the Nasolabial Muscle in Human Fetuses as Determined by Micro-CT Combined With Iodine Staining.

This study aims to investigate the 3-dimensional (3D) anatomical structure of the orbicularis oris and nasalis, which are closely associated with the appearance of the upper lip and lower part of the nose. The relationship of the complicated 3D anatomical structure with the outline shape was also determined. Microcomputed tomography combined with iodine staining was used to scan the nasolabial tissues of 3 aborted fetuses. The strictly aligned, corrected, full-capacity, 2-dimensional (2D) grayscale images obtained were then used to reconstruct 3D structures using a 3D reconstruction software. 2D grayscale slices and a 3D anatomical model of the orbicularis oris and nasalis of the specimens were obtained. The 2D images and the 3D model confirmed the orbicularis oris anatomical structure reported in previous studies and also provided new insights (such as the close association of the formation of the philtral dimple, lip peak, philtral ridge, and nasal sill with the orbicularis oris). In addition, the results show that the nasolabial muscle consists of muscle fibers from different sources and is divided into four distinct parts: pars marginalis, pars peripheralis, muscle fibers of the levator labii superioris, and nasalis muscle fibers. The 3D anatomical structures indicate that the orbicularis oris and nasalis are closely associated with the appearances of the upper lip and lower part of the nose. The results may aid plastic surgeons in performing cleft-lip correction surgery.

Aeração nasal e força muscular respiratória em crianças respiradoras orais

Resumo: OBJETIVO: observar se existe relação entre força muscular respiratória e área da aeração nasal em crianças respiradoras orais. MÉTODOS: trata-se de um estudo do tipo observacional, transversal comparativo entre dois grupos. Participaram 32 crianças com Respiração Oral secundária à rinite alérgica (21 meninos e 11 meninas) e 30 respiradoras nasais sem rinite alérgica (09 meninos e 21 meninas), 7 a 12 anos, submetidas à avaliação da aeração nasal com o espelho de Altmann e à avaliação da força muscular respiratória com o manovacuômetro digital (MVD(r)30). RESULTADOS: não houve correlação entre aeração nasal e força muscular respiratória em cada subgrupo. Houve diferença comparando-se valores das pressões expiratórias máximas entre meninos e meninas respiradores orais (p=0,0064) e entre meninos e meninas respiradores nasais (p=0,0030). Também houve diferença das pressões inspiratórias máximas entre meninos e meninas respiradores orais (p=0,0324) e entre meninos e meninas respiradores nasais (p=0,0210). CONCLUSÃO: não foi possível confirmar a relação entre a área de aeração nasal e a força muscular respiratória nos respiradores orais.

Motor unit number in a small facial muscle, dilator naris.

A loss of functioning motor units underlies many neuromuscular disorders. The facial nerve innervates the muscles of facial expression, including nasal muscles, which also play an important role in the regulation of airflow resistance. It is difficult to accurately assess motor unit number in the facial muscles, because the muscles are difficult to activate in isolation. Here, we apply the manual McComas method to estimate the number of motor units in a nasal dilator muscle. EMG of the dilator naris was recorded during graded stimulation of the zygomatic branch of the facial nerve in 26 subjects (12 males and 14 females), aged 20-41 years. Each subject was studied twice, on separate days, to estimate method reproducibility. As a check on our use of the McComas method, we also estimated motor unit number in the first dorsal interosseus muscle (FDI) of six subjects, as the muscle is also small and has been studied with the McComas method. Reproducibility was evaluated with a rigorous statistical approach, the Bland-Altman procedure. We estimate that dilator naris is composed of 75 ± 15.6 (SD) motor units, compared to 144 ± 35.5 in FDI. The coefficient of variation for test-retest reproducibility of dilator naris motor unit estimates was 29.6 %, similar to separate-day reproducibility reported for other muscles. Recording and stimulation were done with surface electrodes, and the recordings were of high quality and reproducible. This simple technique could be applied clinically to track motor neuron loss and to monitor facial nerve integrity.

Effects of Open Technique Rhinoplasty on Mimicry: Electroneurographic Evaluation.

This study was designed to investigate the effects of open technique rhinoplasty on facial nerve terminal branches more concerned with mimicry via electroneurography (ENoG). Twenty patients ages between 24 and 36 years were included in the study. Five nasal mimicry muscles were used to evaluate axonal loss of the facial nerve: bilateral transverse nasal, levator labii superioris alaeque nasi (LLSAN), and procerus muscles of all patients were evaluated preoperatively and postoperative third month by ENoG. The patients that have abnormalities regarding the amplitude and latency at third month were reevaluated at sixth month postoperatively. Mean latencies of the facial nerve were calculated to be increased for all muscles at third postoperative month, but this increase was significant only for left LLSAN (P = 0.002). Amplitudes of the facial nerve decreased in all of the groups, but this decrease was not significant (P > 0.05). Two patients with exceptionally long latency facial nerve response of transverse nasal muscle and 11 muscle recordings with abnormal low amplitudes of the facial nerve at the third month was reevaluated at sixth postoperative month and the values were improved. This study demonstrated that facial nerve integrity is minimally affected after rhinoplasty, yet all affected muscles were recovered on the long term.