The Anatomy Study of Temporal Region based on Ultrasound Investigation: A Spatial Structure Study.

BACKGROUND: With the growing popularity of rejuvenation, people are giving more concerns on their temporal depression which makes them look older and wishing to improve it by injection. The complex structure of the temporal region leads to a higher risk of failed injection. The temporal region is well understood based on cadaver anatomy, but few studies have described its spatial structure. The purpose of this study was to improve the efficacy and safety of temporal injection by studying the spatial structure of the soft tissues and major blood vessels in each layer of the temporal region. METHODS: A total of 30 volunteers (24 men and 6 women, 60 temporal regions) were investigated. Color Doppler ultrasound was used to measure the thickness of the temporal layers at the selected measurement points (A, B, C, D, E, and F). The maximum thickness of the temporal fat pads was also measured, and the layers, depths and diameters of the major temporal vessels (frontal branch of superficial temporal artery and vein, middle temporal vein and deep temporal artery) were measured. RESULTS: At the various measurement points, the thickness and position of the skin, subcutaneous fat superficial fascia, and temporalis muscle did not differ significantly, whereas the superficial temporal fat pad and deep temporal fat pad differed significantly. The diameter and depth of the superficial temporal artery, superficial temporal vein, and deep temporal artery did not differ significantly, whereas the diameter of the middle temporal vein differed slightly, whereas the depth differed more obviously. CONCLUSIONS: The temporal structure is very complex, and understanding the spatial position of each layer of tissue plays an important role in improving the efficacy and safety of temporal filler injection. Ultrasound can help us to understand this information and assist in therapy. LEVEL OF EVIDENCE: Level II.

Location of the split line of the deep temporal fascia when reducing a zygomatic arch fracture.

BACKGROUND: The deep temporal fascia (DTF) is known to separate into two layers that descend to attach to the zygomatic arch. When surgeons reduce an isolated fracture of the zygomatic arch through a temporal approach, the temporal incision site needs to be superior to the split line of the DTF. MATERIALS AND METHODS: Sixty-seven hemifacial cadavers were investigated after removing the skin, subcutaneous tissue, and superficial temporal fascia. The superficial layer of the DTF was exposed. We cut the superficial layer along the line along, which it adhered to the deep layer inseparably. The heights of the split line of the DTF from the superior border of the zygomatic arch and from the top of the helix were measured at three points: at the jugale, zygion, and 3 cm from the tragus. RESULTS: In all cases there were thick identifiable deep layers of the DTF. The mean heights of the split line of the DTF from the superior border of the zygomatic arch were 49.8, 46.7, and 42.6 mm at the jugale, zygion, and 3 cm from the tragus, respectively; the corresponding mean heights of the split line from the top of the helix were 19.1, 15.6, and 11.4 mm. CONCLUSIONS: Knowledge of the mean height of the split line of the DTF will be helpful for surgeons to determine the temporal incision site for ensuring the safe reduction of a zygomatic arch fracture.

Intraoral Endoscopic Ligation of Maxillary Artery in the Infratemporal Fossa.

Ligation of the sphenopalatine and posterior nasal arteries is indicated for posterior epistaxis as initial treatment or when conservative measures fail. In some patients, a transnasal approach or its alternative transantral approach are not possible due to tumor filling the nasal corridor, pterygopalatine fossa, or maxillary sinus. Aim of this study was to evaluate feasibility of endoscopically assisted transoral approach for the ligation of the maxillary artery (MA). Six fresh cadaver specimens (12 sides), previously prepared with intravascular injections of colored latex, were dissected. A combined transnasal and transoral approach exposed the MA from the deep belly of the temporalis muscle laterally to its terminal branches medially. Anatomical relationships of the MA with the deep belly of the temporalis muscle and the lower head of the lateral pterygoid muscle, and feasibility of access to the MA via a transoral approach were assessed. In all specimens, the MA was found at the point where horizontal fibers of the lower head of the lateral pterygoid muscle cross the vertical fibers of the deep belly of the temporalis muscle. In 5 specimens, the artery ran anteriorly and laterally to lower head of the lateral pterygoid muscle, and in 1 specimen, it ran posteriorly and medially to this muscle, diving between its fibers. The modified endoscopically assisted transoral approach is feasible to ligate the MA. It can be used for proximal vascular control in cases when transnasal and transantral approaches are not viable.

Morphological and morphometric characterization of the "sphenoidal tubercle" / Caracterización morfológica y morfométrica del tubérculo esfenoidal

The sphenoidal tubercle is a bone elevation located in the anterior edge of the infratemporal crest of the sphenoid greater wing, where the temporal and lateral pterygoid muscles have their origin. This bone accident presents varied morphology so its description and denomination are a topic of discussion. 60 dry skulls obtained from the morphology laboratory of the Biomedical Basic Sciences Department of the University of Talca were used for a morphological and morphometric analysis of the sphenoidal tubercle including its morphology, diameters (anteroposterior, transverse and vertical) and the distance to the grooves for the maxillary artery and maxillary nerve. Sphenoidal tubercle had a prevalence of 98.4 % of all dry skulls analyzed with a bilateral presentation in the 76.6 % of the cases. According to its different forms of presentation established by Cáceres et al., (2016) the pyramidal form was the most frequent with a 25.7 %. The average diameters were of 4.12 mm anteroposterior, 5.50 mm transverse and 3.89 mm vertical. The average distance to the grooves of the maxillary artery and maxillary nerve were 9.04 mm and 7.6 mm, respectively. Sphenoidal tubercle is a constant bone accident with a variated morphology and measures. Due to its anatomical relations with important neurovascular elements such as the maxillary artery and the maxillary nerve, it may be used as a reference point for surgical access to the infratemporal fossa. From this analysis we establish that the denomination of "infratemporal process" is more accurate, because the development of this bone accident is from muscular traction performed by the lateral pterygoid muscle and the deep portion of the temporal muscle causing great variations in its morphology, probably due to external and functional parameters or even influenced by the biotype.

El tubérculo esfenoidal es una elevación ósea ubicada en el extremo anterior de la cresta infratemporal del ala mayor del hueso esfenoides, donde presta inserción al músculo temporal y pterigoideo lateral. Presenta morfología variada, por lo que su descripción y denominación resultan motivo de discusión. 60 cráneos secos obtenidos del Laboratorio de Morfología del Departamento de Ciencias Básicas Biomédicas de la Universidad de Talca, fueron utilizados para realizar un análisis morfológico y morfométrico del tubérculo esfenoidal evaluando forma, diámetros (anteroposterior, laterolateral y vertical) y distancia con el surco de la arteria y nervio maxilar. El tubérculo esfenoidal tuvo una prevalencia del 98,4 % del total de cráneos analizados, presentándose bilateralmente en el 76,6 % de los casos. De acuerdo a las diferentes formas de presentación establecidas por Cáceres et al (2016) la forma piramidal fue la más frecuente con un 25,7 %. Los diámetros promedio fueron de 4,12 mm anteroposterior, 5,50 mm laterolateral y 3,89 mm vertical. Las distancias promedio con el surco de la arteria y nervio maxilar fueron de 9,04 mm y 7,6mm, respectivamente. El tubérculo esfenoidal es un accidente óseo constante de morfología y dimensiones variadas. Debido a sus relaciones con elementos vasculares de importancia, tales como la arteria y nervio maxilar, podría ser utilizado como elemento de referencia para el acceso quirúrgico a la fosa infratemporal. A partir de su análisis planteamos que su denominación como "proceso infratemporal" sería más apropiado, debido a que se desarrollaría a partir de la tracción muscular ejercida por el musculo pterigoideo lateral y la porción profunda del músculo temporal, ocasionando variaciones notables en su morfología, probablemente debido a factores externos y funcionales o incluso influenciada por el biotipo.

Does the Deep Layer of the Deep Temporalis Fascia Really Exist?

PURPOSE: It has been widely accepted that a split of the deep temporal fascia occurs approximately 2 to 3 cm above the zygomatic arch and extends into the superficial and deep layers. The deep layer of the deep temporal fascia is between the superficial temporal fat pad and the temporal muscle. However, during procedures, the authors noted the absence of the deep layer of the deep temporal fascia between the superficial temporal fat pad and the temporal muscle. This prospective study was conducted to clarify the presence or absence of a deep layer of the deep temporal fascia. MATERIALS AND METHODS: Anatomic layers of the soft tissues of the temporal region, with reference to the deep temporal fascia, were investigated in 130 cases operated on for zygomaticofacial fractures using the supratemporal approach from June 2013 to June 2017. RESULTS: Of 130 surgeries, the authors found the absence of a thick, obviously identifiable, fascial layer between the superficial temporal fat pad and the temporal muscle. In fact, the authors found nothing above the temporal muscle in most cases. In a few cases, the authors observed only a small amount of scattered loose connective tissue between the superficial temporal fat pad and the temporal muscle. CONCLUSIONS: This clinical study showed the absence of a thick, obviously identifiable, fascial layer between the superficial temporal fat pad and the temporal muscle, which suggests that a "deep layer of the deep temporal fascia" might not exist.

Characterization and morphological comparison of human dura mater, temporalis fascia, and pericranium for the correct selection of an autograft in duraplasty procedures.

PURPOSE: The objective of this study was to characterize and compare the morphological characteristics of the dura mater, the pericranium, and the temporal fascia to ascertain the most adequate tissue to use as a dura graft. METHODS: 20 dura mater, 20 pericranium and 20 temporalis fascia samples were analyzed. Each of the samples was stained with hematoxylin and eosin, orcein, Van Gieson, Masson's trichrome and Verhoeff-Van Gieson (600 slides in total) for a general morphological evaluation, as well as a quantitative, morphometric and densitometric analysis of elastic fibers present in each of the tissues. RESULTS: The micro-densitometric analysis of the tissues indicated that the area occupied by the elastic fibers showed values of 1.766 ± 1.376, 4.580 ± 3.041, and 8.253 ± 4.467 % for the dura mater, the temporalis fascia and the pericranium, respectively (p < 0.05, all pairs). The values observed in the analysis of the density intensity were 3.42E+06 ± 2.57E+06, 1.41E+07 ± 1.28E+07, and 1.63E+07 ± 9.19E+06 for the dura mater, the temporalis fascia and the pericranium, respectively (p < 0.05), dura mater vs. temporalis fascia and dura mater vs. pericranium). CONCLUSIONS: This is the first study to compare the dura mater with tissues for dural autograft and to quantify the elastic component present in these tissues. The results indicate that the temporalis fascia is a better dural graft because of its intrinsic tissue properties.

Postoperative temporal hollowing: Is there a surgical approach that prevents this complication? A systematic review and anatomic illustration.

BACKGROUND: Temporal hollowing is a common complication following surgical dissection in the temporal region. Our objectives were to: (1) review and clarify the temporal soft tissue relationships - supplemented by cadaveric dissection - to better understand surgical approach variations and elucidate potential etiologies of postoperative hollowing; (2) identify if there is any evidence to support a surgical approach that prevents hollowing through a systematic review. METHODS: Cadaveric dissection was performed on six hemi-heads. A systematic review of the literature was undertaken to identify surgical approaches with a decreased risk of postoperative hollowing. RESULTS: A total of 1212 articles were reviewed; 19 of these met final inclusion criteria. Level I and II evidence supports against the use of a dissection plane beneath the superficial layer of the deep temporal fascia or through the intermediate temporal fat pad. Level II evidence supports preservation of the temporalis muscle origin - no evidence is available to support other temporalis resuspension techniques. For intracranial exposure, refraining from temporal fat pad dissection (Level I Evidence) and use of decreased access approaches such as the minipterional craniotomy (Level I Evidence) appear to minimize temporal soft tissue atrophy. CONCLUSIONS: This study highlights the significance of preservation of the temporal soft tissue components to prevent hollowing. Preserving the temporalis origin and avoiding dissection between the leaflets of the deep temporal fascia or through the intermediate temporal fat pad appear to minimize this complication.

Relações entre potenciais elétricos dos músculos temporais e masseteres, força de mordida e índice morfológico da face / Relationship between electrical activity of the temporal and masseter muscles, bite force, and morphological facial index

RESUMO Objetivo Verificar e analisar possíveis correlações entre a atividade elétrica dos músculos temporais e masseteres, a força de mordida e os índices morfológicos da face, em indivíduos adultos. Método Participaram 43 indivíduos, adultos jovens de ambos os gêneros, entre 18 e 37 anos, submetidos à mensuração da face para cálculo do Índice Morfológico da Face (IMF), Eletromiografia de Superfície (EMGs) de Masseteres Direitos e Esquerdos (MD e ME), Temporais Direitos e Esquerdos (TD e TE) e obtenção da Força de Mordida (FM) nas regiões de pré-molares direitos, pré-molares esquerdos e incisivos. As provas eletromiográficas realizadas foram em repouso, Contração Voluntária Isométrica Máxima (CVIM) e mastigação habitual de uva-passa. Foi realizada análise estatística pelo coeficiente de correlação de Spearman com significância no nível de 5%. Resultados Os valores de repouso em TD e TE foram significativamente maiores que os de MD e ME. Foi encontrada correlação direta significativa entre IMF e a EMGs na prova de CVIM para o TE (rs=36, p=0,017). Observou-se correlação direta significativa entre o IMF com a EMGs durante a FM em Incisivos para os músculos TD, TE e Masseter Direito (MD). Durante as provas de força, foi possível observar correlação direta significativa entre a FM em pré-molares direitos com a EMGs do TE, MD, ME. Conclusões Não foi verificada correlação entre as respostas elétricas dos músculos temporais e masseteres, a força de mordida e os índices morfológicos da face, em indivíduos adultos a partir das provas realizadas. A atividade elétrica dos músculos temporais e masseteres parece associar-se apenas à força de mordida. Como dado de característica postural habitual, a atividade elétrica dos músculos temporais é maior que a atividade de masseteres, também independente do IMF.

ABSTRACT Purpose To analyze possible correlations between the electrical activity of masseter and temporal muscles, Bite Force (BF), and Morphological Facial Indices (MFI). Methods The study involved 43 young adults, both genders, 18 to 37 years old. The individuals were submitted to: face measurement to calculate MFI; Masseter and Temporal Surface Electromyography (sEMG) and BF measurements on right and left premolars and incisors. The following electromyographic tests were conducted: at rest position; Maximal Voluntary Isometrical Contraction (MVIC) and usual chewing of raisins. Statistical analysis was conducted using the coefficient of Spearman correlation with significance level of 5%. Results The values at rest in the temporal muscles were significantly higher than those in the masseter muscles. A meaningful correlation was found between MFI and sEMG in the MVIC test for the Left Temporal (rs=36, p=0.017). A significant correlation was observed between FMI and sEMG during BF in incisors for temporal muscles and the Right Masseter. During the force tests, it was possible to observe a meaningful correlation between BF in right premolars and the sEMG of the Left Temporal and Masseters. Conclusion No correlation was found between the sEMG of temporal and masseter muscles, BF, and FMI in adult individuals based on the tests performed. The SEMG of temporal and masseter muscles seems to be associated only with BF. As a datum of habitual postural characteristic, the electrical activity of temporal muscles is higher than the activity of masseters, also regardless of MFI.

[An anatomy study of temporal layers : the safe space for hyaluronic acid injection].

Objective: To determine the safe space for hyaluronic acid(HA) injection through anatomy study of temporal layers. Methods: 6 fresh and 8 formaldehyde-fixed cadaver heads were dissected. The skin soft-tissue layers of temporal region were incised through the cranial coronal plane and elevated layer by layer. The morphological features of layers were observed and documented, as well as the relationship of the superficial temporal artery (STA),the temporal branch of facial nerve (TFN) and the middle temporal vein(MTV) with corresponding layers. Relevant neasurements of the superficial temporal fat pad (sTFD) were recorded. With reference of cardever dissection, temporal region injection with HA was carried out clinically to confirm the safety and effect. Results: In the temporal region, from surface to the temporal fossa, the layers are skin, subcutaneous tissue, superfiacial temporal fascia (STF),loose areolar tissue, superficial layer of deep temporal fascia(sDTF), sTFD, deep layer of deep temporal fascia (dDTF),deep temporal fat pad (dTFD) and temporalis. The temporal skin is tightly attached with the subcutaneous tissue. The STA runs within the subcutaneous tissue on the STF, whereas the TFN within the areolar tissue was just beneath the STF. The loose areolar tissue is a potential layer space. The DTF splits into two sheets of fascia at the line 1 cm above the upper orbital rim to envelope the sTFD, within which the MTV runs backward. The dTFD is the temporal extension of buccal fat pad. With reference of cadever dissection, the target space of temporal HA injection was beneath the temporalis for the area superior to the MTV, whereas within the sTFD for the area inferior to the MTV.67 cases were completed with good result and no complication. Conclusions: In the upper area of temporal region adjacent to the frontal border, the sub-temporalis space is the safety space for HA injection, while inferior to the middle temporal vein and near the zygoma, the superficial temporal fat pad is the target space for safe HA injection.

An Anatomical Study of the Middle Temporal Vein and the Drainage Vascular Networks to Assess the Potential Complications and the Preventive Maneuver During Temporal Augmentation Using Both Anterograde and Retrograde Injections.

BACKGROUND: Non-thrombotic pulmonary embolism has recently been reported as a remote complication of filler injections to correct hollowing in the temporal region. The middle temporal vein (MTV) has been identified as being highly susceptible to accidental injection. METHODS: The anatomy and tributaries of the MTV were investigated in six soft embalmed cadavers. The MTV was cannulated and injected in both anterograde and retrograde directions in ten additional cadavers using saline and black filler, respectively. RESULTS: The course and tributaries of the MTV were described. Regarding the infusion experiment, manual injection of saline was easily infused into the MTV toward the internal jugular vein, resulting in continuous flow of saline drainage. This revealed a direct channel from the MTV to the internal jugular vein. Assessment of a preventive maneuver during filler injections was effectively performed by pressing at the preauricular venous confluent point against the zygomatic process. Sudden retardation of saline flow from the drainage tube situated in the internal jugular vein was observed when the preauricular confluent point was compressed. Injection of black gel filler into the MTV and the tributaries through the cannulated tube directed toward the eye proved difficult. CONCLUSION: The mechanism of venous filler emboli in a clinical setting occurs when the MTV is accidentally cannulated. The filler emboli follow the anterograde venous blood stream to the pulmonary artery causing non-thrombotic pulmonary embolism. Pressing of the pretragal confluent point is strongly recommended during temporal injection to help prevent filler complications, but does not totally eliminate complication occurrence. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors http://www.springer.com/00266 .

Microanatomical Location of Hyaluronic Acid Gel Following Injection of the Temporal Hollows.

PURPOSE: To examine the microanatomical location of hyaluronic acid gel injected within the temporal hollows of cadaver specimens. METHODS: The temporal hollows were injected subcutaneously with hyaluronic acid gel in 6 fresh frozen human cadaver hemifaces. Temporal soft tissues were dissected to a preperiosteal plane and fixated in 95% alcohol. A soft tissue section extending from skin to temporal bone was obtained for each specimen. Histologic examination was performed using hematoxylin and eosin stain. RESULTS: In 5 of 6 specimens, at least 95% of the hyaluronic acid was located within the subcutaneous fat. In 1 of 6 specimens, approximately 35% of the material was located within the subcutaneous fat and 60% was located within the superficial temporal fascia. Two specimens had 5% located within the temporalis muscle. In 1 specimen, hyaluronic acid was found to encompass a superficial muscular artery within the superficial temporal fascia. CONCLUSIONS: This study elucidates the location of hyaluronic acid gel after subcutaneous injection within the temporal hollow. Histology confirmed consistent placement of the gel within the subcutaneous tissues, but it also showed that injection in this region may produce unintended deeper location of filler, and a significant perivascular collection of the material. The proximity of dense temporal fascial and muscle arterial networks in this region may pose risk for perivascular injection and associated complications.

Experience and anatomical study of modified lengthening temporalis myoplasty for established facial paralysis.

Lengthening temporalis myoplasty, reported by Daniel Labbé in 1997, is a unique and definite facial reanimation procedure that involves moving the whole temporal muscle anteroinferiorly and inserting its tendon directly into the nasolabial fold. In the present article, we report our experience in the use of his modified method of the procedure, which preserves the zygomatic arch by transecting the coronoid process through the nasolabial fold incision. We also describe our cadaveric study that aimed to elucidate a secure approach for coronoid process transection. We performed this procedure in five patients with permanent facial paralysis. To improve facial symmetry, we also performed several additional static reconstructions such as T-shaped double-sleeve fascia grafts for lower lip deformities. We were successful in achieving considerable static improvement at rest, immediately after the surgery, and the recovery of facial movement was apparent approximately 3 months after the surgery. With regard to the cadaveric study, we noted that the entry to the buccal fat region, which is also the pathway of the temporal fascia, was a narrow space, and a short transection of the medial upper edge of the masseter fascia would make it easy to locate the coronoid process. Therefore, for a safe and secure access to the coronoid process from the nasolabial fold, we believe that we should first expose the cranial side and continue to dissect along the side and lower edge of the maxilla to locate the medial upper edge of the masseter fascia. By transecting along its edge, we could easily access the coronoid process, located immediately behind it, and widen the pathway of the temporal fascia. This modified method is less invasive and simpler compared to the original procedure, and understanding the detailed anatomy for dissection would help surgeons perform this procedure more confidently.

[The study of stomatognathic muscles morphological changes after zygomatic plasty combined with mandibular angel plasty].

OBJECTIVE: To investigate the morphology change of stomatognathic muscles after zygomatic plasty combined with mandibular angel plasty. METHODS: 3D-CT facial soft tissue measurement was performed pre-operative and at 10 days,3 months post-operatively in 59 cases with prominent malar-complex and mandibular angle. The q test (Newman-Keuls method) was used to analyze the variance. RESULTS: The cross sectional area of masseter muscle and medial pterygoid muscle were both increased at 10 days, reduced at 3 months post-operatively (P < 0.05). The masseter muscle and medial pterygoid muscle cross sectional areas were (4.73 +/- 0.21) cm2 and (3.24 +/- 0.21) cm2 at anterior nasal spine plane, respectively; the pterygoid muscle cross-sectional area was (1.37 +/- 0.35 ) cm2 at the root of coronoid process plane, showing significant difference, when comparing with those before operation (P < 0.05). Lateral pterygoid muscle and temporal muscle had no statistical difference between the pre-and 10 days post-operatively(P > 0.05), however, the temporal muscle was reduced while the lateral pterygoid muscle was increased at 3 months post-operatively. The temporal muscle cross-sectional area was(2.35 + 0.25) cm2 at coronoid process plane; the temporal muscle and lateral pterygoid muscle cross-sectional areas were (1.00 +/- 0.16) cm2 and (3.54 +/- 0.61) cm2 at the root of coronoid process plane, which were significantly different from those before operation (P < 0.05 ). CONCLUSIONS: Because of osteotomy, muscles attached position are changed in the short term after zygomatic plasty combined with mandibular angel plasty. Masseter muscle and medial pterygoid muscle are inevitably injuried during the operation. With the postoperative recovery, muscles have adaptive changes which reduced compared with those before operation after their reattachment. Zygomatic plasty can cause temporal muscle atrophy;while the lateral pterygoid muscle is rarely involved, the cross sectional area had no statistical difference between the pre- and 10 days post-operative, and the cross sectional area increase at 3 months post-operatively may be due to a compensational enlargement.

The suborbicularis oculi fat (SOOF) and the fascial planes: has everything already been explained?

IMPORTANCE: During anatomic and surgical dissections, a connection was seen between the superficial layer of the deep temporal fascia and the prezygomatic area. These findings were in contrast to previous evaluations. This study defines this connection, which is important to understand from both surgical and anatomic standpoints. OBJECTIVE: To define the connection between the superficial layer of the deep temporal fascia and the prezygomatic area and demonstrate the presence of a deep fascial layer in the midface. DESIGN AND SETTING: Anatomical study performed at the Laboratoire d'Anatomie de la Faculté de Médecine de Nice, Sophia Antipolis, France; at the Centre du Don des Corps de l'Université Paris Descartes, Paris, France; and at the Department of Experimental Medicine, Histology, and Embryology Unit of the University of Pavia, Pavia, Italy. Twenty-four hemifaces of 14 white cadavers were dissected to define the relationship between deep temporal fascia and the midface. Four biopsy samples were harvested for histologic analysis. MAIN OUTCOMES AND MEASURES: Dissection of 24 hemifaces from the fresh cadavers revealed the following findings. There is a connection of the deep fascia of the temple (superficial layer of deep temporal fascia) to the midface that divides the fat deep to the orbicularis muscle into 2 layers. One layer of fat is the so-called suborbicularis oculi fat (SOOF), which is superficial to the deep fascia, and the other layer of fat (preperiosteal) is deep to the deep fascia and adherent to malar bone. These findings are in contrast to previous anatomical findings. RESULTS In 12 hemifaces, the superficial layer of the deep temporal fascia directly reached the prezygomatic area as a continuous fascial layer. In 16 hemifaces, the superficial sheet of the deep temporal fascia inserted at the level of the zygomatic and lateral orbital rim and continued as a deep fascial layer over the prezygomatic area. In all specimens, a deep fascial layer was present in the prezygomatic-infraorbital area. This deep fascial layer is adherent to the muscles of the infraorbital area, and it divided the fat located deep to the orbicularis oculi muscle into 2 layers: the SOOF and a deeper layer. Histologic examination of the biopsy samples confirmed these findings. CONCLUSIONS AND RELEVANCE: This study demonstrates the existence of a deep fascial layer in the midface. This fascia is connected to the superficial layer of the deep temporal fascia, and it divides the fat deep to the orbicularis oculi muscle into 2 layers. This new finding carries interesting implications related to the classic concept of the superficial musculoaponeurotic system. LEVEL OF EVIDENCE: NA.

Sphenomandibular muscle or deep bundle of temporal muscle? / ¿Músculo esfenomandibular o fascículo profundo del músculo temporal?

The muscle designated by a group of authors as the sphenomandibular or, according to recent studies, the deep bundle of the temporal muscle, presents important anatomical relationships, especially in a medical-odontological context. In view of this divergence, the aim of the present study was to observe the morphology by means of dissection of the formaldehyde-preserved heads, using two different techniques to access the muscle region in question, designated as trans-zygomatic and frontal access routes. The results permitted, by observation of the dissections frontally, the presence of fascicles standing apart from the deep bundle muscle venter, which was named intermediary bundle. This bundle presented two portions, a meaty upper portion and a tendinous lower portion, which continues with the tendinous part of the superficial bundle present on the internal surface of the coronoid process. In view of the material observations, it can be concluded that, due to the total absence of muscular fascia between its bundles, the temporal muscle is a unique entity presenting three bundles ­ the deep, the intermediate and the superficial.

El músculo denominado como esfenomandibular por un grupo de autores o de acuerdo con estudios recientes, de fascículo profundo del músculo temporal, presenta importantes relaciones anatómicas, especialmente en un contexto médico-odontológico. En vista de esta discusión, el objetivo fue observar la morfología mediante la disección de cabezas conservadas en formaldehído, utilizando dos técnicas diferentes para acceder a la región del músculo, designadas como vías de acceso trans-cigomáticas y frontales. Los resultados mostraron, por la observación de las disecciones frontales, la presencia de fascículos que se ubican independientemente al vientre muscular del fascículo profundo, denominado fascículo intermediario. Este fascículo presentó dos porciones, una superior carnosa y una inferior tendinosa, que continuó con la parte tendinosa del fascículo superficial presente en la superficie interna del proceso coronoides. En vista de las observaciones realizadas, se puede concluir que debido a la ausencia total de la fascia muscular entre sus paquetes, el músculo temporal es una entidad única que presenta tres fascículos, el profundo, intermedio y superficial.

Temporal morphomics as a model for determining preoperative risk of blood transfusion in nonsyndromic craniosynostosis patients.

BACKGROUND: Estimates of blood loss during craniosynostosis surgeries have ranged from 42 to 126 percent of infant's total blood volume. Currently, no risk model has been developed to determine the likelihood of needing a blood transfusion. The authors propose an objective model, based on patients' three-dimensional anatomical characteristics, to stratify the likelihood of needing perioperative packed red blood cells. METHODS: High-throughput image analysis from already ordered preoperative computed tomographic scans was used to reconstruct the three-dimensional anatomy of the temporalis muscle and overlying temporal fat pad. Using these morphomic measurements, the authors created a risk assessment model of the amount of packed red blood cells infused based on morphomic variations in temporal soft tissue. RESULTS: The authors evaluated 139 infants with nonsyndromic craniosynostosis from the University of Michigan Health System. Results show the need for blood transfusion ranged from 94.1 percent among patients in the smallest quartile for temporal fat pad volume compared with 65.7 percent among the group with the largest quartile for temporal fat pad volume (p = 0.0057). Using multivariable linear regression, temporal fat pad volume (p = 0.012) and fat pad thickness (p = 0.036) were independent predictors for amount of packed red blood cells required. CONCLUSIONS: The authors demonstrate that patients with diminished temporal fat pad volume are significantly more likely to need increased packed red blood cell transfusions. In addition, by use of multivariable linear regression, their data suggest that temporal fat pad volume and thickness were independent predictors for the amount of required transfusion of packed red blood cells.

Clinical anatomy of the periocular region.

The aims of this article are twofold: (1) to provide the facial plastic surgeon with a comprehensive and up-to-date overview of periocular anatomy including the brow, midface, and temporal region and (2) to highlight important anatomical relationships that must be appreciated in order to achieve the best possible functional and aesthetic surgical outcomes.

Muscle fiber type composition, fiber diameter, capillary density in temporalis and masseter muscles and correlation with bite force / Tipos de fibras musculares, diámetro de fibras y densidad capilar en los músculos masetero y temporal y su correlación con la fuerza de mordida

The jaw muscles are essential components in the stomatognatic system. Their complex architecture allows them to execute several motor tasks. One of the structural peculiarities is the presence of hybrid and neonatal fibers.We studied the differences of the fiber-type in masseter and temporalis muscles along the first to nineth decades in both genders. Seventy-four (74) samples were analyzed by immunohistochemistry. Slow and fast muscle fibers distribution was similar in both muscles in both genders. Hybrid fiber was observed in all decades, and its frequency decreased significantly (p<0.001) with aging in masseter. Neonatal myosin expression was observed in all decades, its expression was more frequent in masseter (p=0.01), and males in temporalis (p=0.025). Decrease of the cross sectional area of fast and slow fibers, and decrease of capillary density were detected with aging. These morpho-immunohistochemical alterations on masseter and temporalis muscles correlated to the decrease in bite force with aging.

Los músculos cráneomandibulares son componentes esenciales en el sistema estomatognático. Su arquitectura compleja les permite ejecutar variadas tareas motoras. Una de sus características estructurales es la presencia de fibras musculares híbridas y neonatales. Se estudiaron las diferencias del tipo de fibra en los músculos masetero y temporal en la primera a novena décadas dela vida en ambos sexos. Setenta y cuatro (74) muestras se analizaron por inmunohistoquímica. La distribución de lãs fibras musculares lentas y rápidas fue similar en ambos músculos en ambos sexos. Fibras musculares híbridas fueron observadas en todas las décadas, pero su frecuencia disminuyó significativamente (p <0,001) con el envejecimiento en el masétero. La expresión de miosina neonatal se observo em todas los grupos analizados, aunque su expresión era más frecuente en los músculos maseteros (p = 0,01) y en varones en el temporal (p = 0,025). Se observo una disminución del área de la sección transversal de las fibras rápidas y lentas, y disminución de la densidad capilar al aumentar La edad. Estas alteraciones morfológicas en los músculos masetero y temporal se correlacionan con la disminución de la fuerza asociada al envejecimiento.

Split temporalis muscle flap anatomy, vascularization and clinical applications.

INTRODUCTION: For more than a century, the temporalis muscle has been used for facial reconstructions. More recently, a split temporalis muscle flap elevated on the superficial temporal pedicle has been described, for which the resulting gain of length makes crossing of the midline possible, as well as reconstruction of substance losses exceeding the midline. MATERIALS AND METHODS: Fourteen fresh cadaveric dissections were performed to study the different techniques for splitting the temporalis muscle. Dissections with catheterization and injection of radio-opaque contrasting agent in the external carotid artery were then performed to specify the vascularization of the flap split on the superficial temporal pedicle. RESULTS: The duplication of the superficial temporal pedicle grants greater length compared to that of the deep pedicles, 57 mm versus 40 (p = 0.036). The middle temporal artery is capable of ensuring the vascularization, and therefore the viability, of the split flap. From these results, we spoke about the limitations of this study and we have inferred the main indications.