Determination of age and sex using bimastoid diameter: a cone beam computed tomography Study / Deteminación de la edad y el sexo mediante el diámetro bimastoide: un estudio en tomografía computarizada de haz cónico (CBCT)

Abstract This study aimed to investigate the possibility of age and sex determination using bimastoid diameter with cone-beam computed tomography (CBCT). This retrospective study investigated 100 female and 100 male patients aged 18-83 years (mean age: 45.55±16.28 years). To measure bimastoid diameter, the appropriate image was chosen from sagittal, coronal, and axial images of CBCT in which the measurement points could be best detected. The distance between the points of the mastoid process was measured using three-dimensional coronal reconstruction. The mean bimastoid breadth was 106.12±6.22mm. The bimastoid diameter in male cases was higher than that in female cases (110.69±4.53mm vs. 101.65±4.00mm). There was no significant difference in bimastoid breadth with advancing age. For sex determination, morphometric measurements of bimastoid diameter ensured a high rate of dimorphism in the Turkish subpopulation. CBCT morphometric analysis may be reliable and convenient for evaluating sex and may be recommended to compare population data.

Resumen Este estudio tuvo como objetivo investigar la posibilidad de determinar la edad y el sexo utilizando el diámetro bimastoideo con tomografía computarizada de haz cónico (CBCT). Este estudio retrospectivo investigó a 100 mujeres y 100 hombres de entre 18 y 83 años (edad media: 45,55±16,28 años). Para medir el diámetro bimastoideo, se eligió la imagen adecuada de las imágenes sagital, coronal y axial de CBCT en las que los puntos de medición se podían detectar mejor. La distancia entre los puntos del proceso mastoideo se midió mediante reconstrucción coronal tridimensional. La amplitud media del bimastoide fue de 106,12± 6,22mm. El diámetro del bimastoide en los casos masculinos fue mayor que en los casos femeninos (110,69±4,53 mm frente a 101,65±4,00mm). No hubo diferencias significativas en la amplitud del bimastoide con la edad. Para la determinación del sexo, las mediciones morfométricas del diámetro bimastoide aseguraron una alta tasa de dimorfismo en la subpoblación turca. El análisis morfométrico CBCT puede ser confiable y conveniente para evaluar el sexo y puede recomendarse para comparar datos poblacionales.

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.

Estudio morfométrico del punto asterional y su relación con los senos venosos durales / Morphometric study of the asterional point and its relationship with the dural venous sinuses

INTRODUCCIÓN: la importancia de conocer las diferentes reparaciones anatómicas que involucran la parte ósea de la fosa posterior con estructuras neurovasculares, disminuye la incidencia de complicaciones relacionadas con su acceso dentro del procedimiento neuroquirúrgico. MATERIALES Y MÉTODOS: estudio descriptivo basado en la evaluación de 90 hemicráneas secas, del Museo de Anatomía de la Universidad Mayor de San Andrés. RESULTADOS: la prevalencia de asterión tipo I fue de 28.9%, mientras que la de tipo II fue de 71.1%. La prevalencia del número de venas emisarias fue: una vena 54.4%, dos venas 42.2% y tres venas 3.3%. Los promedios para las características morfométricas son los siguientes: de Asterion a protuberancia occipital externa de 68.8 mm, de Asterion a cresta suprameatal de 50.1 mm, de Asterion a vena emisaria de 54.1 mm, de Asterion a Vértice del proceso mastoideo de 54.1 mm y de asterion a plano horizontal de Francfort 14.6 mm. La ubicación del asterión en el seno transverso fue la siguiente: al mismo nivel del seno, 47.8% de los casos, en el codo en 13.3%, superior al seno 31.1% e inferior a este en el 7.8%. CONCLUSIONES: hay una diferencia en algunos resultados morfométricos del asterión con respecto a otros autores, lo que podría determinar una configuración craneal diferente para nuestra población. Esto debe considerarse para evitar complicaciones durante el período transoperatorio en una cirugía de fosa posterior. Estos resultados reflejan la necesidad de realizar un estudio con una población más grande para obtener resultados reales, estableciendo así parámetros de corte que nos permitirán tener nuestra propia bibliografía sobre cómo proceder en nuestra actividad quirúrgica.

INTRODUCTION: the importance of knowing the different anatomical repairs that involve the bony part of the posterior fossa with neurovascular structures, decreases the incidence of complications related to its access within the neurosurgical procedure. MATERIALS AND METHODS: descriptive study based on the evaluation of 90 dry hemicranial, from the Anatomy Museum of the Universidad Mayor de San Andrés. RESULTS: the prevalence of asterion type I was 28.9%, while that of type II was 71.1%. The prevalence of the number of emissary veins was: One vein 54.4%, Two veins 42.2% and Three veins 3.3%. The averages for morphometric characteristics are as follows: from Asterion to external occipital protuberance 68.8 mm, from Asterion to suprameatal crest 50.1 mm, from Asterion to emissary vein 54.1 mm, from Asterion to Vertex from the mastoid process 54.1 mm and from asterion to horizontal plane of Frankfurt 14.6 mm. The location of asterion in the transverse sinus was the following: at the same level of the sinus 47.8% of the cases, in the elbow in 13.3%, superior to the sinus 31.1% and inferior to this in the 7.8%. CONCLUSIONS: there is a difference in some morphometric results of the asterion with respect to other authors, which could determine a different cranial configuration for our population. This should be considered to avoid complications during the transoperative period in a posterior fossa surgery. These results reflect the need to carry out a study with a larger population, in order to have real results, thus establishing cutting parameters that will allow us to have our own bibliography on how to proceed in our surgical activity.

Study of Sigmoid Sinus Variations in the Temporal Bone by Micro Dissection and its Classification - A Cadaveric Study

Abstract Introduction Sigmoid sinus (SS) variations have been classified variously in the literature. These classifications suffer from some form of shortcoming from a clinical point of view for their application. Objective We propose a clinically relevant classification of the SS in relation to the posterior semicircular canal (PSCC) and to the exposure of the presigmoid dural plate. The positioning of the SS was analyzed with reference to the volume of themastoid and to the level of mastoid pneumatization. Methods A total of 94 formalin-preserved human cadaveric temporal bones were microdissected to carry out a complete mastoidectomy. The SS, the presigmoid dural plate, and the PSCCwere exposed, and the position of the former was analyzed in relation to the latter two in order to classify the position of the SS into three grades. Results GradeI hadthebest exposureof the presigmoid dura andof the PSCC,while grade III had the poorest exposure of the presigmoid dura and of the PSCC. Grade I SS was associated with good pneumatization and highermastoid volumescompared with grades II and III. Conclusions The SS exhibits considerable anatomic variability. A favorable positioning of the SS is associated with a large mastoid volume and pneumatization. A careful preoperative study of the imaging may help in understanding the positioning of the SS and the safety of various transmastoid approaches.

Síndrome de Eagle: relato de caso / Eagle Syndrome: a case report

A síndrome de Eagle é uma condição rara e com etiologia ainda não bem estabelecida, a qual se deve ter bastante suspeição para seu correto tratamento. Seu tratamento deve ser definido em conjunto com o paciente, seja ele conservador ou cirúrgico, sempre levando em consideração as expectativas do paciente, além da maior expertise do profissional na modalidade escolhida para o tratamento. Neste artigo, apresentamos uma paciente de 35 anos atendida no Hospital Felício Rocho, discutindo os diversos aspectos da doença, inclusive a modalidade de tratamento escolhida para o caso.

Eagle syndrome is a rare condition, and its etiology has not yet been well established and its correct treatment is uncertain. Its treatment must be defined together with the patient, be it conservative or surgical, always taking into consideration the patient's expectations, in addition to a solid professional expertise in the modality chosen for the treatment. In this article, we present the case of a 35-year-old patient who was admitted to the Felício Rocho Hospital and discuss the various aspects of the disease, including the treatment modality chosen for the case.

Prevalencia y características morfométricas del foramen mastoideo y vena emisaria mastoidea en población mexicana / Prevalence and morphometric characteristics of mastoid foramen and mastoid emmisary vein in the Mexican population

Las descripciones anatómicas del foramen mastoideo (FM) y la vena emisaria mastoidea (VEM) son escasas en la literatura. Dicho conocimiento es fundamental para realizar un abordaje quirúrgico de la fosa craneal posterior o región mastoidea. El objetivo del estudio fue determinar la prevalencia, variantes y características morfométricas del FM y VEM en población mexicana. Se evaluaron 176 hemicráneos por dos observadores independientes cegados el uno del otro, se determinaron la prevalencia, número y características morfométricas. La prevalencia del FM entre los dos lados fue de 75% con una mayor frecuencia de forámenes del lado izquierdo comparado con el lado derecho; respecto al número de forámenes se encontraron 108 hemicráneos con un foramen único, 22 con doble foramen y 2 con triple foramen. La prevalencia del FM y VEM fue de 75%, siendo la variante única la más frecuente.

The anatomic descriptions of mastoid foramen (MF) and mastoid emissary vein (MEV) are lacking in the literature. This knowledge is fundamental for the surgeon who is about to perform surgery of the posterior fossa or mastoid region. This study aims to determine the prevalence of MF and MEV in Mexican population, determine the morphometric characteristics of MF and describe possible variations in the number, size, location and asymmetry. In this study 88 craniums were evaluated (176 hemicranium) by two independent observers who did not have access to information of each other´s results. The prevalence, number and the morphometric characteristics were determined. MF prevalence of the two sides of the skull was 75 % with a higher frequency of the left foramina compared to the right side; in reference to the number of foramina we found 108 hemicranium with a single MF, 22 double and 2 triple foramen. In conclusion, the prevalence of MF and MEV in this study is 75%, this single variant noted as being the most frequent.

Relação entre área e volume da mastoide em adultos brasileiros / Mastoid surface area-to-volume ratios in adult Brazilian individuals

As medidas de área e volume da mastoide por tomografia computadorizada não foram previamente descritas em adultos brasileiros. O conhecimento dessas medidas é muito importante para o entendimento da fisiologia da orelha média e seus estados patológicos, refletindo diretamente na pneumatização mastoídea. OBJETIVO: Verificar a existência de relação entre a área e o volume da mastoide. MÉTODO: Estudo de coorte contemporânea com corte transversal, no qual 28 pacientes foram submetidos à tomografia de mastoides. Foram reconstruídas as medidas de área e volume das mastoides por cortes seriados usando o software Image Pro Plus. RESULTADOS: Os volumes das mastoides variaram de 5,5 até 72,4 cm³. As áreas variaram de 43,9 até 525,2 cm². A área da mastoide foi uma função linear do volume. CONCLUSÃO: As medidas de área e volume da mastoide em adultos brasileiros seguem uma correlação linear, concordando com estudos realizados em outros países. As médias de área e volume encontradas foram superiores às previamente publicadas, ao contrário da média da relação área/volume, que foi inferior. Futuros estudos, com número maior de indivíduos, poderão esclarecer se a população brasileira tem ou não maiores médias de área e volume da mastoide em relação a outras populações específicas.

Computed tomography-based measurements of mastoid surface area and volume have not been described for adult Brazilian individuals. These measurements add to the understanding of middle ear physiology, related diseases, and their impact on mastoid pneumatization. OBJECTIVE: To check the ratio between mastoid surface area and volume. METHOD: This contemporary cross-sectional cohort study included 28 patients submitted to CT imaging of the mastoid. Measurements of surface area and volume were made based on serial CT scans and produced with the aid of software package Image Pro Plus. RESULTS: Mastoid volumes ranged from 5.5 to 72.4 cm³. Surface areas ranged from 43.9 to 525.2 cm². Surface areas varied linearly with volumes. CONCLUSION: Mastoid surface areas and volumes of adult Brazilian subjects followed a linear correlation, as also described in studies carried out in other countries. Mean surface areas and volumes were higher than previously published, unlike surface area-to-volume ratios, which were lower. Further studies with larger populations will provide evidence as to whether Brazilian subjects have larger surface areas and volumes than other populations.

Emissary foramens of the human skull: anatomical characteristics and its relations with clinical neurosurgery / Forámenes emisarios del cráneo humano: características anatómicas y sus relaciones con la neurocirugía clínica

The recognition of emissary foramens is important not only for understanding the regional neurovascular anatomy, but also to distinguish normal from potentially abnormal structures. Thus, the aim of this study was to review the literature on anatomical and clinical aspects of the mastoid, parietal and sphenoid emissary foramens. It was found that the emissary foramen presents importance in clinical practice because it acts as a route of spread of extracranial infection to the intracranial structures and also possible complications in neurosurgery, due to its influence in the performance of techniques such as radiofrequency rhizotomy for treatment of trigeminal neuralgia. The anatomical knowledge of the emissary foramens is important due to variability in their incidence in the human skull and its relation to the dura mater sinuses.

El reconocimiento de forámenes emisarios es importante no sólo para la comprensión de la anatomía neurovascular regional, sino también para distinguir lo normal a partir de estructuras potencialmente anormales. El objetivo de este estudio fue revisar la literatura sobre los aspectos anatómicos y clínicos del proceso mastoide, huesos parietal y esfenoides y forámenes emisarios. El foramen emisario adquiere importancia en la práctica clínica debido a que actúa como una vía de propagación de la infección extracraneal a las estructuras intracraneales, y también con las posibles complicaciones en neurocirugía, debido a su influencia en el desarrollo de técnicas como rizotomía por radiofrecuencia en el tratamiento de neuralgia del trigémino. El conocimiento anatómico de los forámenes emisarios es importante debido a la variabilidad en su incidencia en el cráneo humano y su relación con los senos de la duramadre.

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.

Evaluating accuracy and precisión in morphologic traits for sexual dimorphism in malnutrition human skull: a comparative study

One of the most important purposes of anthropological studies of human skeletons protocol is the determination of sex. Some skulls may be wrongly classified due to systemic conditions presented during the life of individuals who affected the muscle forces that act on bones, as is the case of severe malnutrition. The purpose of this study is to analyze the effect of severe malnutrition on morphological determinants of sexual dimorphism classically studied in the visual analysis of the skull. 163 human skulls were analized with sex, age and cause of death known, belonging to the collection of Universidad Federal de Sao Paulo (UNIFESP). We performed visual inspection of the skull and diagnosis of sex based on size and overall architecture of the skull, an aspect of the zygomatic bone, size and roughness of the mastoid process, ridges of the occipital bone and general appearance of the jaw. The skulls were classified into two groups according to whether severe malnutrition had described in his cause of death (n=60) or had other cause of death (n=103). The results of the inspection were compared with the registry to determine the accuracy in diagnosis and sensitivity of the method for male and female in both groups analyzed. In the group with malnutrition the best indicator was the appearance of the zygomatic bone, with a 86.6 percent accuracy. In another group closely was found in the size of the mastoid (87.3 percent). In both groups the highest values of sensitivity were for male (83.3-95.3 percent). The sensitivity to female showed lower values in the group without malnutrition (69.2-76.9 percent) than in the group with malnutrition (72.4-89.65 percent), these differences were statistically significant (p<0.05 ).

Uno de los propósitos más importantes del protocolo antropológico de estudios de osamentas humanas, es la determinación del sexo. Algunos cráneos pueden ser clasificados erróneamente debido a condiciones sistémicas presentadas durante la vida de individuos que hayan afectado a las fuerzas musculares que actúan sobre el hueso, como es el caso de la desnutrición severa. El propósito de este estudio fue determinar la exactitud y confiabilidad, sobre los parámetros morfológicos determinantes de dimorfismo sexual, clásicamente estudiados en el análisis visual del cráneo, para los dos grupos que componen la muestra, uno con desnutrición acompañando el momento del deceso y otro con causa de muerte sin ese factor acompañante. Se utilizaron 163 cráneos humanos de sexo, edad y causa de muerte conocido, pertenecientes a la colección de la UNIFESP. Se realizaron la inspección visual del cráneo y el diagnóstico de sexo en base a: tamaño y arquitectura general del cráneo, aspecto del hueso cigomático, tamaño y rugosidades del proceso mastoides, rugosidades del hueso occipital y aspecto general de la mandíbula. Los cráneos fueron clasificados en dos grupos, de acuerdo a si presentaron desnutrición severa descrita en su causa de muerte (n=60) o presentaban otra causa de muerte (n=103). Los resultados de la inspección se compararon con la del registro para determinar la exactitud en el diagnóstico y la sensibilidad del método para hombres y mujeres, en los dos grupos analizados. En el grupo con desnutrición, el mejor indicador resultó el aspecto del hueso cigomático, con un 86,6 por ciento de exactitud. En el otro grupo, la mayor exactitud se encontró en el tamaño del proceso mastoides (87,3 por ciento). En ambos grupos, los mayores valores de sensibilidad fueron para hombres (83,3-95,3 por ciento). La sensibilidad para mujeres presentó menores valores en el grupo sin desnutrición (69,2-76,9 por ciento) que en el grupo con desnutrición (72,4-89,65 por...

Células mastóideas: revisão anatomofuncional / Mastoid cells: anatomofunctional review

Modelo do estudo: revisão bibliográfica.Objetivo(s) do estudo: ampliar os conhecimentos sobre o desenvolvimento e pneumatizaçãodo osso temporal, bem como compreender a distribuição pelo osso das células mastóideascom suas características etárias e sexuais.

Research model: bibliography reviewing. Intends: maximize the knowledge aboutthe development and pneumatization of the temporal bone, understanding the mastoid air cellsdistribution over the bone, regarding sexual and ages characteristics.

Morphometric examination of the paranasal sinuses and mastoid air cells using computed tomography

The paranasal sinuses and mastoid air cells vary considerably in size and shape from person to person. The main structures are pneumatic. In this study, we investigated the relationship between right and left sides and evaluated the volume changes according to age and sex. Of all patients attending the radiology department, 91 cases without paranasal sinuses and mastoid air cells pathology [i.e., inflammation, operation or trauma] were selected for evaluation. Axial computed tomography [CT] scans were obtained for both paranasal sinuses and temporal bones. In all scans, the volumes of each area [maxillary sinus, frontal sinus, sphenoid sinus and mastoid air cell] were calculated and analyzed statistically. The volumes of paranasal sinuses and mastoid air cells increased with age and women had a lower mean volume. There was a positive correlation between right-left and ipsilateral structures [paranasal sinuses and mastoid air cells]. These results are helpful in understanding the normal and pathological conditions of the paranasal sinuses and the mastoid air cells

The Relationship between Presbycusis and Mastoid Pneumatization

Presbycusis is defined as the natural hearing loss accompanying aging, caused by degenerative changes in the inner ear. The etiology of presbycusis is uncertain. However, it would appear that a complex genetic cause is most likely. The determinants of mastoid size continue to be controversial. One of the pneumatization theories is the hereditary theory. In this study, the possible relationship between presbycusis and the extent of mastoid pneumatization was investigated. This study was carried out on 21 patients with presbycusis and 21 normal subjects of similar ages. The pneumatized volume was measured by computerized tomography. The temporal bone was scanned at 2 mm thickness intervals. Exposure (kV 130, mA105). The scan plane was parallel to the orbitomeatal line and the CT images covered the entire mastoid region. The average mastoid pneumatization in presbycusis group was 6.08 +/- 2.52 cm3 in the right ear and 6.19 +/- 2.93 cm3 in the left ear. However, in the control group it was 4.69 +/- 3.17 cm3 in the right ear (p=0.12) and 5.10 +/- 3.49 cm3 in the left ear (p=0.28). No significant difference was found between the presbycusis patients and normal subjects in terms of the volume of mastoid pneumatization.

Neumatocele craneal de origen mastoideo / Cranial pneumatocele of mastoid origin

Se presenta el caso de un paciente con neumatocele intracraneal espontáneo de origen mastoideo. Se le aplicó metilmetacrilato en la trompa de Eustaquio y se le colocó un tubo de ventilación en la membrana timpánica para lograr que saliera el aire atrapado. Su evolución fue tórpida, por lo que se requirió craneoplastia. Se hace un análisis del diagnóstico, el cual se efectuó con placas simples de cráneo, angiografía vertebral y carotídea, tomografía computarizada y estudio otoneurológico completo

O seio sigmóide no acesso mastóide ao nervo facial e conduto-auditivo interno / Sigmoid sinus in mastoid access to facial nerve and internal auditory pathway

Os autores estudam as medidas anatômicas do seio sigmóide em relaçäo ao nervo facial, no seu segundo joelho e na emergência do nervo-corda do tímpano, com o intuito de prevenir-se para abordagem cirúrgica de mastóide, especialmente para ouvido interno. Foi elaborada uma relaçäo anatômica/radiográfica a partir de medidas de 52 ossos temporais humanos dissecados. A partir dessa previsäo pode o cirurgiäo prevenir-se quanto à possibilidade de ter que afastar o seio sigmóide para estes procedimentos