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Medial Portion (medial + portion)
Selected AbstractsA Method of Augmenting the Cheek Area Through SMAS, subSMAS, and Subcutaneous Tissue Recruitment During Facelift SurgeryDERMATOLOGIC SURGERY, Issue 3 2003Dominic A. Brandy MD BACKGROUND As the human face ages, there is a depletion of fat that occurs in the submalar region. Various techniques such as fat transfers, fillers, alloplastic implants, and composite rhytidectomies have been used to augment this area in the past. OBJECTIVE To describe a technique that augments the submalar areas during facelift surgery without the use of fat transfer, fillers, alloplastic implants, or a risky composite technique. METHOD An oval is scribed over the depressed submalar areas preoperatively. During facelift surgery, a fusiform area is scribed over the SMAS. This fusiform is scribed so that the medial end is directed at the center of the submalar depression, and the lateral end is toward the posterior earlobe. A defect is created within the lateral aspect of the fusiform, but not the medial portion. The fusiform is subsequently closed with a 2-0 Ethibond suture using three horizontal mattress sutures and two interrupted sutures. Upon closure of this defect, SMAS, subSMAS, and subcutaneous tissue overlying the SMAS are recruited into the submalar defect by the simple phenomenon of dog-ear formation. Additionally, there is a component of frank elevation of the tissues inferior to the medial aspect of the fusiform and submalar space. RESULTS The aforementioned technique has been performed on 123 patients over 7 years and has resulted in consistently good improvement in the submalar space. The procedure is not difficult to learn, and good results can be achieved with initial cases. The learning curve was not found to be steep, with good results being achieved quickly. CONCLUSION Depression of the submalar space plays a significant role in creating an aged face. In the past, various fillers and/or alloplastic implants have been used to augment this region. A low-risk method is described that mobilizes SMAS, subSMAS, and subcutaneous tissues into the submalar space through the phenomenon of dog-ear formation after fusiform closure. [source] Photoperiodic differences in a forebrain nucleus involved in vocal plasticity: Enkephalin immunoreactivity reveals volumetric variation in song nucleus lMAN but not NIf in male European starlings (Sturnus vulgaris)DEVELOPMENTAL NEUROBIOLOGY, Issue 11 2010Tyler J. Stevenson Abstract Seasonal variation in the volume of various song control nuclei in many passerine species remains one of the best examples of naturally occurring adult neuroplasticity among vertebrates. The lateral portion of the magnocellular nucleus of the anterior nidopallium (lMAN) is a song nucleus that is important for song learning and seems to be critical for inducing variability in the song structure that is later pruned via a feedback process to produce adult crystallized song. To date, lMAN has not been shown to exhibit seasonal changes in volume, probably because it is difficult to resolve the boundaries of lMAN when employing histological methods based on Nissl staining. Here, lMANcore volumes were examined in intact photostimulated (i.e., breeding), castrated photostimulated and photorefractory (i.e., nonbreeding) male starlings (Sturnus vulgaris) to investigate the degree of seasonal variation in brain morphology. We present data demonstrating that the volumes of the total MAN and lMANcore delineated by enkephalin immunoreactivity are greater in photostimulated male starlings as compared to photorefractory males. Moreover, two other regions associated with the song system that have not been investigated previously in the context of seasonal plasticity namely (i) the medial portion of MAN (mMAN), and (ii) the nucleus interfacialis (NIf) did not display significant volumetric variation. We propose that greater lMANcore volumes are associated with the increase in vocal plasticity that is generally observed prior to production of stereotyped song. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 70: 751,763, 2010 [source] A possible case of coccidioidomycosis from the Los Muertos site, Tempe, ArizonaINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 4 2006D. H. Temple Abstract Coccidioidomycosis is a fungal disease endemic to southwestern North America and parts of Central and South America. Coccidioidomycosis frequently disseminates to the human skeleton and produces mostly lytic skeletal lesions. However, this disease is infrequently described within archaeological populations. As a result, it is important to report potential cases in order to improve current understanding of the appearance and distribution of lesions resulting from coccidioidomycosis in archaeological specimens. This study describes skeletal lesions in an adult male recovered from the Los Muertos site, Tempe, Arizona (AD 500,1450). These lesions are present on the inferior border of the left scapular spine, the medial portion of the left first metacarpal head, and the medial portion of the right first metatarsal. The lesions are predominantly lytic with sclerotic and, in some cases, healed cortical bone distributed around their margins. Evidence of skeletal healing is recorded within the destructive focus of one lesion. Geographical information on pathogen endemism, overall lesion distribution, and agricultural-era Hohokom behaviour suggest that coccidioidomycosis is the most likely diagnostic option for these lesions. Mounting evidence for possible infections in the palaeopathological literature, combined with high frequencies of nutritional stress levels in endemic regions, suggests that coccidioidomycosis contributed at least moderately to morbidity in the American Southwest. Copyright © 2006 John Wiley & Sons, Ltd. [source] Evaluation of the chondral modeling theory using fe-simulation and numeric shape optimizationJOURNAL OF ANATOMY, Issue 5 2009Jeffrey H. Plochocki Abstract The chondral modeling theory proposes that hydrostatic pressure within articular cartilage regulates joint size, shape, and congruence through regional variations in rates of tissue proliferation. The purpose of this study is to develop a computational model using a nonlinear two-dimensional finite element analysis in conjunction with numeric shape optimization to evaluate the chondral modeling theory. The model employed in this analysis is generated from an MR image of the medial portion of the tibiofemoral joint in a subadult male. Stress-regulated morphological changes are simulated until skeletal maturity and evaluated against the chondral modeling theory. The computed results are found to support the chondral modeling theory. The shape-optimized model exhibits increased joint congruence, broader stress distributions in articular cartilage, and a relative decrease in joint diameter. The results for the computational model correspond well with experimental data and provide valuable insights into the mechanical determinants of joint growth. The model also provides a crucial first step toward developing a comprehensive model that can be employed to test the influence of mechanical variables on joint conformation. [source] Arctic roars , laryngeal anatomy and vocalization of the muskox (Ovibos moschatus Zimmermann, 1780, Bovidae)JOURNAL OF ZOOLOGY, Issue 4 2006R. Frey Abstract The impressive roaring of adult male muskoxen most often occurs during rutting contests. Roaring in adult females is primarily relevant to mother,infant communication. Loud roars are produced by taking up a specific roaring posture. Acoustic recordings were made in a small herd of zoo muskoxen during three successive rutting seasons. Earlier recordings of a different herd were used for comparison. Head-and-neck specimens were subjected to vascular injection, macroscopic anatomical dissection, computer tomographic analysis and skeletonization. Isolated preserved larynges of young animals were dissected for ontogenetic comparison. Despite a pronounced sexual dimorphism of head mass, larynx size is almost identical in adult male and female muskoxen, as is the fundamental frequency of their roars. Remarkably, the larynges of both sexes of muskoxen are provided with an unpaired ventrorostral ventricle. Probably, this ventricle is inflated during the initial phase of a roar. The ventricle may have two functions: to increase the amplitude of roaring and to darken the timbre of the roars by acting as an additional resonance space. The vocal fold of adult female and young individuals has a sharp rostral edge and a vocal ligament is still present. During male ontogeny the vocal ligament becomes transformed into a large fat pad extending into the wall of the laryngeal vestibulum. Accordingly, the glottic region in the adult male lacks any sharp edges of the mucosa. In both sexes the thyroarytenoid muscle is divided into three portions. A single roar may comprise phases of different sound volume. The roars of both muskox sexes are characterized by a pulsed structure. We suggest that two oscillating systems are involved in the production of roars: one comprising only the medial portion of the vocal fold and one including its lateral portion. [source] A Quantitative Study of the Medial Surface Dynamics of an In Vivo Canine Vocal Fold during Phonation,THE LARYNGOSCOPE, Issue 9 2005Michael Doellinger PhD Abstract Objectives/Hypothesis: The purpose of this study was to measure the medial surface dynamics of a canine vocal fold during phonation. In particular, displacements, velocities, accelerations, and relative phase velocities of vocal fold fleshpoints were reported across the entire medial surface. Although the medial surface dynamics have a profound influence on voice production, such data are rare because of the inaccessibility of the vocal folds. Study Design: Medial surface dynamics were investigated during both normal and fry-like phonation as a function of innervation to the recurrent laryngeal nerve for conditions of constant glottal airflow. Methods: An in vivo canine model was used. The larynx was dissected similar to methods described in previous excised hemilarynx experiments. Phonation was induced with artificial airflow and innervation to the recurrent laryngeal nerve. The recordings were obtained using a high-speed digital imaging system. Three dimensional coordinates were computed for fleshpoints along the entire medial surface. The trajectories of the fleshpoints were preprocessed using the method of Empirical Eigenfunctions. Results: Although considerable variability existed within the data, in general, the medial-lateral displacements and vertical displacements of the vocal fold fleshpoints were large compared with anterior-posterior displacements. For both normal and fry-like phonation, the largest displacements and velocities were concentrated in the upper medial portion. During normal phonation, the mucosal wave propagated primarily in a vertical direction. Above a certain threshold of subglottal pressure (or stimulation to the recurrent laryngeal nerve), an abrupt transition from chest-like to fry-like phonation was observed. Conclusions: The study reports unique, quantitative data regarding the medial surface dynamics of an in vivo canine vocal fold during phonation, capturing both chest-like and fry-like vibration patterns. These data quantify a complex set of dynamics. The mathematical modeling of such complexity is still in its infancy and requires quantitative data of this nature for development, validation, and testing. [source] Homologous Collagen Substances for Vocal Fold AugmentationTHE LARYNGOSCOPE, Issue 5 2001Mark S. Courey MD Abstract Objectives/Hypothesis Dysphonia resulting from failure of glottic closure during voicing is a difficult clinical problem. Recently developed homologous collagen compounds may be beneficial in treating this problem. The objectives of this thesis are to: 1) evaluate the potential site(s) of collagen graft placement in the human vocal fold, quantify the amount of graft material that can be injected into these sites, and determine how these sites are accessed by the currently available surgical tools for injection; 2) determine the effects of the superficial vocal fold implant on laryngeal vibratory patterns and characterize how the implant affects the forces required to bring vocal folds into an adducted position for vibration; and 3) evaluate the host response to two different forms of cadaveric collagen. Study Design Prospective laboratory. Methods Three separate experiments were undertaken: 1) Eight cadaver larynges were injected with collagen compounds through a 27-gauge needle. The amount of substance required to medialize the vocal fold and potential positions for graft placement were evaluated. 2) Six cadaver larynges were mounted on a stabilizing stand while airflow, vocal fold length, adduction forces, and abduction forces on the vocal folds were manipulated. Vibratory patterns before and after the injection of the vocal folds with solubilized collagen were assessed. 3) A nude mouse model was used to study the host response to two different exogenous collagen compounds. Results Solubilized collagen compounds could be injected reliably into the superficial layer of the lamina propria (SLLP), medial portion of the thyroarytenoid muscle, or lateral portion of the thyroarytenoid muscle. When injected superficially, significantly less material was required to displace the medial edge of the vocal fold to midline (P = .0001). When graft material was placed into the medial portion of the thyroarytenoid (TA) muscle, the forces required to bring the vocal fold into a position suitable for vibration were significantly reduced (P = .0106) and the vibratory patterns of the vocal folds were not impaired. Both AlloDerm® and Dermalogen® solubilized preparations of human dermal tissue were well tolerated in the nude-mouse model. Minimal inflammatory reaction occurred. Small amounts of graft material were identified histologically at the end of the 6-month study period. The graft material appeared organized and had been infiltrated with fibroblasts of host origin. Conclusions Homologous collagen compounds can be reliably injected into the cadaveric human larynx. When the substances are injected into the medial portion of the TA muscle, immediately deep to the vocal ligament, they decrease the force of contraction needed to bring the vocal folds into a position adequate for phonation and have minimal affect on the vibratory patterns. These forms of homologous collagen are well tolerated. A small amount persists over a 6-month interval. These materials warrant further clinical trials in human subjects. [source] Correction of involutional lower eyelid medial ectropion with transconjunctival approach retractor plication and lateral tarsal stripACTA OPHTHALMOLOGICA, Issue 2 2006Kenneth C. S. Fong Abstract. Aim:,We describe the technique and our results in managing lower eyelid involutional medial ectropion using a combination of lateral tarsal strip to address horizontal eyelid laxity, and transconjunctival inferior retractor plication to address inferior retractor dehiscence. Methods:,Patients with symptoms of epiphora or signs of medial ectropion were offered this procedure. All had the following characteristics: medial lower eyelid eversion, punctal eversion >3 mm, medial canthal tendon laxity <4 mm, significant horizontal eyelid laxity and lacrimal systems that were patent to syringing. Results:,A total of 24 eyelids of 17 patients underwent this procedure over a 12-month period. The mean age of the patients was 79.7 years; 11 were male and six were female. The mean follow-up time was 18 months. Two eyes had undergone previous surgery. All patients had restoration of the eyelid margin to the globe and relief of symptoms. No complications were noted. Discussion:,These results suggest that excision of posterior lamellar tissue is not necessary for correction of involutional medial ectropion. Transconjunctival plication or reattachment of retractors is easy to perform and allows for the repair of more than the medial portion of the retractors if required. [source] Levator palpebrae superioris muscle in human fetuses: Anatomical findings and their clinical relevanceCLINICAL ANATOMY, Issue 7 2005J. Plock Abstract Accessory medial muscular bellies of the levator palpebrae superioris muscle and broad lateral insertion of its aponeurosis into tissue near the lacrimal gland have been reported as rare variations in adults. The anatomy of this muscle was studied in orbits of ten human fetuses between the 5th and 10th months of gestation. In each of the dissected orbits, the levator palpebrae superioris muscle had a broad lateral insertion into the capsule of the lacrimal gland or the periorbita, in this period of development. In addition, medial accessory muscles of the levator or singular muscle fibers within fibrous bands that inserted near the trochlear region and the medial portion of the upper eyelid were present in 70% of the fetuses, either unilaterally or bilaterally. These findings demonstrate new unreported aspects of levator palpebrae superioris development and morphology. Our findings suggest that an initial broad anterior primary anlage of the muscle is followed by secondary atrophy of lesser used marginal portions of this muscle, which are replaced by delicate connective tissue. These findings might force new considerations about diagnostic and therapeutic approaches to congenital mobility disorders of the levator palpebrae superioris muscle, such as blepharoptosis or eyelid retraction. The clinical relevance of our results are discussed along with a review of the embryogenesis of extraocular muscles and soft tissue of the orbit. Clin. Anat. 18:473,480, 2005. © 2005 Wiley-Liss, Inc. [source] Early onset of deafening-induced song deterioration and differential requirements of the pallial-basal ganglia vocal pathwayEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2008Haruhito Horita Abstract Similar to humans, songbirds rely on auditory feedback to maintain the acoustic and sequence structure of adult learned vocalizations. When songbirds are deafened, the learned features of song, such as syllable structure and sequencing, eventually deteriorate. However, the time-course and initial phases of song deterioration have not been well studied, particularly in the most commonly studied songbird, the zebra finch. Here, we observed previously uncharacterized subtle but significant changes to learned song within a few days following deafening. Syllable structure became detectably noisier and silent intervals between song motifs increased. Although song motif sequences remained stable at 2 weeks, as previously reported, pronounced changes occurred in longer stretches of song bout sequences. These included deletions of syllables between song motifs, changes in the frequency at which specific chunks of song were produced and stuttering for birds that had some repetitions of syllables before deafening. Changes in syllable structure and song bout sequence occurred at different rates, indicating different mechanisms for their deterioration. The changes in syllable structure required an intact lateral part but not the medial part of the pallial-basal ganglia vocal pathway, whereas changes in the song bout sequence did not require lateral or medial portions of the pathway. These findings indicate that deafening-induced song changes in zebra finches can be detected rapidly after deafening, that acoustic and sequence changes can occur independently, and that, within this time period, the pallial-basal ganglia vocal pathway controls the acoustic structure changes but not the song bout sequence changes. [source] | ||||||||||||||||||||||