Mastoid and opisthion-bimastoid triangles for sex determination in a Brazilian sample / Triangulos mastoideo y opistión-bimastoideo para la determinación del sexo en una muestra brasileña

SUMMARY: Human identification involving mutilation, advanced decomposition, and skeletonized materials is a challenge for professionals in forensic medicine and dentistry. This study was aimed at a morphometric analysis of the mastoid and bimastoid triangles to determine sex in a Brazilian population. The sample included 80 human skulls (34 females and 46 males; age: 18 to 60 years) from individuals with death certificates. Linear measurements (mm) of the mastoid process - right (n=3) and left (n=3) - and the opisthion- bimastoid (n=3) triangles were taken (digital caliper) by two previously trained researchers. Three cranial points - asterion, porion and process - were determined for the right and left mastoid triangle and three others - (1) opisthion and (2) right and (3) left mastoid - for the bimastoid triangle. Heron's formula was used to calculate the area of the triangles assessed. Data were submitted to the Shapiro- Wilk normality test, followed by the unpaired Student's t test or the Mann-Whitney U test, depending on the data distribution verified in the normality test (GraphPad Prism 5.01; p<0.05). The ROC curve was used to measure the accuracy of the variables toward sex determination. The opisthion-bimastoid triangle showed high accuracy and significant differences in all the variables assessed and thus was considered a potential element for sex determination in the Brazilian population assessed.

RESUMEN: La identificación humana que comprende la mutilación, descomposición avanzada y materiales esqueletizados, es un desafío para los profesionales de la medicina forense y de la odontología. Este estudio tuvo como objetivo un análisis morfométrico de los triángulos mastoideo y bimastoideo para determinar el sexo en una población brasileña. La muestra incluyó 80 cráneos humanos (34 mujeres y 46 hombres; edad: 18 a 60 años) de sujetos con certificado de defunción. Se tomaron las medidas lineales (mm) del proceso mastoides - derecha (n = 3) e izquierda (n = 3) - y los triángulos opistion-bimastoide (n = 3) (caliper digital) por dos investigadores previamente entrenados. Se determinaron tres puntos craneales - asterion, porion y proceso mastoides - para el triángulo mastoideo derecho e izquierdo y otros tres - (1) opistion y (2) proceso mastoides derecho e izquierdo - para el triángulo bimastoideo. Se utilizó la fórmula de Heron para calcular el área de los triángulos evaluados. Los datos se analizaron con la prueba de normalidad de Shapiro-Wilk, seguida de la prueba t de Student para datos no apareados o la prueba U de Mann-Whitney, según la distribución de datos verificada en la prueba de normalidad (GraphPad Prism 5.01; p <0.05). La curva ROC se utilizó para medir la precisión de las variables hacia la determinación del sexo. El triángulo opistion-bimastoide mostró una alta precisión y diferencias significativas en todas las variables evaluadas, por lo que se consideró un elemento probable para la determinación del sexo en la población brasileña evaluada.

Sex determination by osteometric assessment of the mastoid process using Cone Beam Computed Tomography / Determinação do sexo em uma população Iraniana por avaliação osteométrica do processo mastóide em imagens de TCFC

Objective: Sex determination is one of the most important parameters to identify in forensic science. Because the mastoid process is the most resistant to damage due to its position in the skull base, it can be used for sex determination. The purpose of this study was to measure the dimensions and convexity and internal angles of the mastoid process to present a model of sex determination in Iranian population. Material and methods: This study was performed on three-dimensional images of 190 Cone Beam Computed Tomography (CBCT) of 105 women and 85 men. On each CBCT the distance between the porion and the mastoid (PM), mastoid length (ML), the distance between the mastoidale and the mastoid incision (M-I), the mastoid height (MH), the mastoid width (MW), intermastoidale distance (IMD) the lateral surfaces of the left and right mastoids (IMLSD) and the Mastoid medial convergence angle (MMCA) was measured on both the right and the left. The data were analyzed by descriptive statistics, t-test, and discriminant function analysis. Results: Significant differences were found for all variables except MMCA and MF in both sex. All measured variables except MW were greater for men than women. The discriminant model achieved a total accuracy of 93.7%. Among the measured factors IMD and IMSLD had the most influence on sex determination. Conclusion: Measuring the dimensions of the mastoid process is a very good method for sex determination with high accuracy of 90% (AU)

Objetivo: A determinação do sexo é um dos parâmetros mais importantes para identificação na ciência forense. Por ser o processo mastóide resistente a danos, devido a sua posição na base do crânio, este poderia ser usado na determinação do sexo. O objetivo deste estudo foi mensurar as dimensões, convexidade e ângulos internos do processo mastóide para apresentar um modelo de determinação do sexo em uma população Iraniana. Material e métodos: Este estudo foi realizado em 190 imagens de tomografia computadorizada de feixe cônico (TCFC), sendo 105 mulheres e 85 homens. Em cada TCFC foram realizadas medidas no processo mastóide em comprimento (ML), altura (MH), largura (MW) em ambos os lados direito e esquerdo, também foi medida a distância entre o Pórion e o processo mastóide (PM), distância até incisura mastoidea (M-I), distância entre as superfícies mediais (IMD) distância entre as superfícies laterais dos processos direito e esquerdo (IMLSD) e o ângulo de convergência medial (MMCA). Os dados foram analisados por estatística descritiva, teste t e análise de função discriminante. Resultados: Diferenças significativas foram encontradas para todas as variáveis, exceto MMCA e MF em ambos os sexos. Todas as variáveis medidas, exceto MW, foram maiores para os homens do que para as mulheres. O modelo de análise de função discriminante alcançou uma precisão total de 93,7%. Entre os fatores medidos, o IMD e o IMSLD tiveram a maior influência na determinação do sexo. Conclusão: Podemos concluir que as dimensões do processo mastóide constituem um método para determinação do sexo, em população Iraniana, com precisão de 90% (AU)

A 3D-Computed Tomography Angiography Study to Help in Surgical Planning for Retrosigmoid Craniotomies

Aims and Objectives: It is impossible to precisely anticipate the course of the transverse and sigmoid sinuses and theirindividual relationship to superficial landmarks such as the asterion during retrosigmoid approaches. This study was done todetermine the position of the asterion and the relationship between asterion and the transverse-sigmoid sinus junction (TSSJ)in making precise burr hole without damaging sinuses during retrosigmoid craniotomies.Materials and Methods: Computed tomography (CT) angiography was performed in 50 patients to obtain 3D-CT volumerendering images of cranial bone and dural sinuses. After delineating the sinuses, by simple restructuring using software andopacity modulation, bone image is reinforced. Asterion type, distance from the tip of mastoid process to asterion and root ofzygoma (ROZ) to asterion, and location of asterion in relation to TSSJ and distance between asterion and TSSJ were analyzedand measured.Results: The incidence of type 1 (presence of sutural bones) in our study was 24% and type 2 (absence of sutural bones) was76%. There was no statistically significance in the side and gender differences. The distance between the asterion and fromthe ROZ was 54.70 ± 3.68 on the right side and 54.32 ± 3.41 on the left side (P-0.612). The distance between asterion and tipof mastoid was 50.51 ± 2.67 on the right side and 50.12 ± 3.06 on the left side (P-0.716). The asterion was located on the T-Ssinus complex in 36 (72%) cases. The asterion was below the T-S sinus complex in 13 (26%) cases, and above the T-S sinuscomplex in only 1 (2%) cases.Conclusion: 3D-CT volume rendering imaging is capable of accurately visualizing the bony landmark and dural sinuses. Aneasy and simple restructured image provides precision and safety for the patient by ready and easy localization of asterionand TSSJ. This study was done to show that the previous cadaver-based anatomical studies can be done now in a moresophisticated and accurate manner with the latest technological advancements. This offers new options for anatomic researchand morphometric investigations.

Morphometric features of asterion in adult human skulls.

Background: Asterion is the meeting point of temporal, occipital and parietal bones on the posterolateral surface of skull and surgically an important point of reference for approaching the posterior cranial fossa structures. However surgeons have been skeptical about its reliability due to population based differences in its morphology, distance with other external landmarks and also to sigmoid and transverse sinuses. Methods: In this study 50 (27 male & 23 female) adult skulls were investigated to determine the type of asterion, its distance from important bony landmarks and also the nearby venous sinuses were measured. Results: Our study revealed that type II (absence of sutural bones) was commoner than type I (presence of sutural bones) asterion. The asterion was 4.82 ± 0.58 cm from tip of the mastoid process on the right side and 4.70 ± 0.70 cm on the left. It was greater in males than in females, p value being statistically significant (P = 0.00 & P = 0.02 for right & left sides respectively). The distance of asterion from supramastoid crest was 4.22 ± 0.73 cm on the right and 4.23+/-0.58 cm on the left. The distance in males was more than in females. The P value 0.00 was statistically significant on the right side. Regarding the position of the asterion in relation to transverse sinus, it was on the transverse sinus in 62% cases, below it in 32% and above in 6%. Conclusions: The data obtained shows that the asterion is located either at the level or below the level of the transverse sinus in majority of the cases. This information is useful to neurosurgeons to reduce the risk during posterior cranial fossa surgeries. This work will also be useful to anthropologists, forensic science experts for determination of sex of the skull along with other parameters.

Craniofacial Dimorphism in Young Jordanian Adults.

Aims: Was to develop a gender determination technique for young Jordanian adult population. Study Design: using osteometric data, from Cephalometric images, and discriminate function analysis. Place and Duration of Study: Section of Clinical Dentistry of the Jordan University Hospital, between October 2013 and July 2014. Methodology: A total of 146 randomly selected digital lateral cephalometric radiographs of young Jordanian adult patients were employed in the investigation, 47 patients were males and 99 were females. For each lateral cephalometric radiograph, one observer using a customized analysis created in Viewbox 4-Cephalometric Software subroutines digitized 19 craniofacial skeletal landmarks. Utilizing the digitized landmarks, 18 measurements that comprised 14 linear, 3 angular and 1 proportional parameters were carried out. Results: The results demonstrated that, with the exception of the Menton to Gonion distance, i. e., the length of the mandibular body, the mean values of all other parameters of male subjects were statistically significantly larger (p<0.05) than those for females. Mastoid height was found to be the best single predictor of gender and can provide an accuracy rate of 82.2%. Using Stepwise method revealed four dimensions (mastoid height, mastoid width, glabella to supraglabellare-nasion distance, and the length of skull base)were found to form the best combination of parameters most precisely depict the best possible prediction, raising the classification accuracy up to 87.7%. Conclusion: A discriminant function equation specific for Jordanian population has also been derived from cranio-mandibular variables. The equation can now be used for a calculable and more precise prediction of gender of Jordanian young adult population.

Auricle reconstruction with expanded auricle posterior flap on mastoidea and auto rib cartilage bracket for repair of congenital microtia / 中华医学美学美容杂志

Objective To explore the clinical effect of auricle reconstruction with expanded auricle posterior flap on mastoidea and auto rib cartilage bracket for repair of congenital microtia.Methods Twenty-one eligible patients with congenital auricle malformation and defect were recruited into this study and three-stage operation was performed.A 50 ml kidney-shaped expander was implanted at mastoid process area to expand skin in stage Ⅰ surgery,followed by a regular affusion to expand skin for 3 to 4 months.The average total waterflood was (80.51 ± 3.87) ml.The volume remained stable for 1 month,once up to the predetermined amount.In stage Ⅱ surgery autogenous costal cartilage was taken and carved into inverted conch shape.Auricle was reconstructed with the expanded flap to cover the auto rib cartilage bracket.The stage Ⅲ surgery was performed for details dressing of the auricle after 3 months.Results All 21 cases underwent operation successfully.Reconstructed ear auricles were similar to uninjured sides in size and shape.Both doctors and patients were contented with the auricles.Conclusions Expanded auricle posterior flap on mastoidea can cover the auto rib cartilage bracket.Autologous costal cartilage can be carved to four layers cartilage bracket that likes an inverted conch,and followed by realistic postoperative auricular shape and strong three-dimensional sense after operation.

Sex determination using mastoid process measurements in Brazilian skulls

The mastoid process characteristics are of great utility in the diagnosis of sex. De Paiva & Segre (2003) described that sex diagnosis was possible based on the determination of the area of the triangle formed by the points porion, mastoidale, and asterion. The purpose of this study was to determine the existence of sexual dimorphism in the dimensions and the area of the mastoid triangle using statistical and discriminant function analysis. A total of 81 skulls of Brazilian individuals that were part of the Museum of the Federal University of Sao Paulo (UNIFESP) collection were used, with sex and ages known: 50 men and 31 women between 40 and 70 years of age (mean 51.58 years, SD 7.319). Most of the lineal dimensions and the calculated areas were higher in men than in women. Only the distance porion-mastoidale, the area of the right mastoid triangle and the total area, was higher and more significant in men with p < 0.01. The analysis of the discriminant function showed that the group of analyzed lineal dimensions presents a low discriminant capacity (Lambda of Wilks = 0.960, Canonical Correlation = 0.199); only porion-mastoidale allowed one to distinguish men's groups from women with a general accuracy of 64.2 percent, but with a high sensibility to classify men (93 percent) and a very low sensibility for women (17.7 percent). These results indicate that the determination of sex based on the dimensions of the mastoid triangle leads to underestimate the women, henee being of less utility in practice.

Las características del proceso mastoides son de gran utilidad para el diagnóstico del sexo. De Paiva & Segre (2003) describieron que era posible el diagnóstico del sexo, en base a la determinación del área del triángulo formado entre los puntos porion, mastoidale y asterion. El propósito de este estudio fue determinar la existencia de dimorfismo sexual en las dimensiones y el área del triángulo mastoideo, mediante análisis estadístico y de función discriminante. Se utilizaron 81 cráneos de individuos Brasileños, pertenecientes a la colección de la UNIFESP, de sexo y edad conocidos, 50 hombres y 31 mujeres, de entre 40 y 70 años (media 51.58 años, DS 7.319). La mayoría de las dimensiones lineales y las áreas calculadas fueron mayores en hombres que en mujeres. Sólo la distancia porion-mastoidale (Po-Ma), el área del triángulo mastoideo derecho y el área total resultaron mayores y significativas en hombres con p<0.01. El análisis de la función discriminante mostró que el conjunto de dimensiones lineales analizadas presenta un bajo poder discriminante (Lambda de Wilks= 0.960, Correlación Canónica= 0.199), sólo Po-Ma permitió clasificar en grupos de hombres y de mujeres con una exactitud general del 64.2 por ciento, con una alta sensibilidad para clasificar hombres (93 por ciento) y una muy baja sensibilidad para mujeres (17.7 por ciento). Estos resultados indican que la determinación del sexo en base a las dimensiones del triángulo mastoideo, tiende a subestimar a las mujeres, siendo de baja utilidad en la práctica.

Uso do cimento de osso alfa-tricálcio-fosfato no tratamento cirúrgico da cavidade mastóidea / Use of alpha-tricalcium phosphate bone cement in the surgical treatment of mastoid cavity

Introdução: A mastoidectomia cavidade aberta pode gerar algumas complicações e a obliteração da cavidade mastóidea é uma técnica descrita e estudada para a eliminação desta cavidade. Materiais aloplásticos têm sido estudados em cirurgias de obliteração da cavidade mastóidea. O cimento de osso alfa-tricálcio-fosfato é um material composto por cálcio e fosfato e apresenta composição bioquímica semelhante à fase mineral do osso. Objetivo: Estudar a biocompatibilidade do cimento de osso alfa-tricálcio-fosfato na obliteração da cavidade mastóidea em "guinea pigs". Método: Vinte "guinea pig" foram submetidos a procedimento cirúrgico. Em 10 cobaias (grupo cimento) a bula timpânica foi obliterada com o cimento de osso alfa-tricálcio-fosfato e em 10 cobaias (grupo controle) a cavidade foi deixada sem preenchimento. Os animais foram avaliados quanto à presença de sinais clínicos de rejeição ao material e outras complicações. Os ossos temporais foram removidos e avaliados quanto ao tipo e o grau de resposta inflamatória e o grau de ossificação. Resultados: Entre as cobaias que completaram o estudo não foram observados sinais de complicações em nenhum caso. Também não foi observado presença de reação inflamatória crônica tipo corpo estranho em nenhuma amostra de ambos os grupos. Quanto ao grau de ossificação, a média dos escores de ossificação no grupo controle (3,5) foi maior que o observado no grupo cimento (1,0). Conclusões: 1) O cimento de osso alfa-tricálcio-fosfato é biocompatível em osso temporal de cobaia. 2) O cimento de osso alfatricálcio- fosfato sofre remodelação óssea, porém não apresenta propriedade de osteocondução.

Introduction: Open cavity mastoidectomy can generate some complications and mastoid cavity obliteration is a technique described and studied for the elimination of this cavity. Alloplastic materials have been studied in mastoid cavity obliteration surgery. Alpha-tricalcium phosphate bone cement is a material composed by calcium and phosphate and presents biochemical characteristics similar to the bone mineral phase. Objective: This study is aimed at evaluating the biocompatibility of alpha-tricalcium phosphate bone cement in the obliteration of the mastoid cavity in guinea pigs. Methods: 20 guinea pigs were submitted to surgical procedure. In 10 cement study group animals, the tympanic bulla was obliterated with alpha-tricalcium phosphate bone cement and in 10 guinea pigs (control group), the cavity was left unfilled. The animals were evaluated for clinical signs of material rejection and other complications. The temporal bones were removed and analyzed as for the type and degree of inflammatory response, as well as the degree of ossification. Results: In the animals that completed the study, there were no complications. There were not either the presence of foreign body inflammatory reaction in none of the samples of both groups. As for the ossification degree, the average ossification scores in the control group (3.5) was greater than that shown by the cement group (1.0). Conclusions: 1) The alpha-tricalcium phosphate bone cement is biocompatible in guinea pig's temporal bone 2) The alphatricalcium phosphate bone cement undergoes bone remodeling, but it doesnït present osteoconductive properties.

Effects of low frequency electric stimulation at bilateral mastoid processes on focal cerebral ischemia-reperfusion in rats / 中华物理医学与康复杂志

Objective To study the protective effects of low frequency electric stimulation at bilateral mastoid processes on the focal cerebral lesion induced by ischemia-reperfusion in rats. Methods Focal cerebral ischemia in rats was produced by 2 hours of the middle cerebral artery occlusion (MCAO) and 24 hours reperfusion. The neurological deficits scale was used to evaluate and screen the rats for tests. The cerebral water content was determined by wet/dry weighing method. The infarct volume was measured by 2,3,5-triphenyltetrazolium chloride (TTC) staining technique and image analysis instrument. The activity of superoxide dismutase (SOD) and the content of malondialdehyde (MDA) in ischemic tissue of brain were analyzed. Results Compared with the control group, the severity of cerebral edema in the treatment group, apart from the emergency group,was lessened(P