Pterion formation in North Indian population: an anatomico-clinical study / Formación del pterion en una población del norte de India: un estudio anátomo-clínico

Pterion is a point of sutural confluence seen in the norma lateralis where frontal, parietal, temporal and sphenoid bones meet. This craniometric point is related to various structures in the cranial cavity like middle meningeal artery, anterior pole of insula and Broca's area. This study was done to find most common variation in its shape and presence of epipteric bones and to compare with other racial groups from previous study. Fifty adult human skulls of unknown sex taken from Department of Anatomy, Sri Guru Ram Das Institute of Medical Sciences and Rsearch, Vallah (Amritsar, India) were examined on both sides for the type and position of the pterion. Four types of pterion formation were noted. Sphenoparietal was observed in 89%, frontotemporal in 7%, stellate in 4% and epipteric in 12% of cases. The pterion was found to be 3.1±0.44 cm on the right side, 3.4±0.40 cm on the left side from the frontozygomatic suture and 4.1±0.45 cm on the right side and 4.4±0.32 cm on the left side from the centre of zygoma. These variations in the sutural morphology is comparable to other population. Its position is of interest to anthropologists, forensic pathologists and surgeons who deserve further investigation in population of different area.

El pterion es un punto correspondiente con el extremo posterior de la sutura donde se ubican los huesos frontal, parietal, temporal y esfenoides. Este punto métrico del cráneo se relaciona con diversas estructuras en la cavidad craneal como la arteria meníngea media y polo anterior de la ínsula en el área de Broca. Este estudio se realizó para determinar la variación más común de la forma y presencia de huesos epiptéricos y comparar estos con otros grupos raciales. Cincuenta cráneos humanos adultos de sexo desconocido obtenidos en el departamento de anatomía, Sri Guru Ram Das Instituto de Ciencias Médicas e Investigaciones, Vallah (Amritsar, India) fueron examinados en ambos lados para el tipo y posición del pterion. Se observaron cuatro tipos de formación. Esfenoparietal en el 89% de las muestras, fronto temporal en el 7% de las muestras, estrelladas en 4% y epiptérico en el 12% de los casos. Desde la sutura frontocigomática el pterion se encontraba a 3,1±0,44 cm en el lado derecho, 3,4±0,40 cm en el lado izquierdo y desde el centro del hueso cigomático a 4,1±0,45 cm en el lado derecho y 4,4±0,32 cm en el lado izquierdo. Estas variaciones en la morfología de la sutura son comparables a otras poblaciones. Su posición es de interés para los antropólogos, patólogos forenses y cirujanos, y merece una mayor investigación en poblaciones de diferentes regiones.

Comparative morphometric study of the sigmoid sinus sulcus and the jugular foramen / Estudo morfométrico comparativo do sulco do seio sigmóideo e do forame jugular

Objective To compare the right and left sides of the same skulls as far as the described landmarks are concerned, and establish the craniometric differences between them. Method We carried out measurements in 50 adult dry human skulls comparing both sides. Results The sigmoid sinus width at the sinodural angle level was larger on the right side in 78% of the cases and at the level of the digastric notch in 72%. The jugular foramen width was also larger on the right side in 84% of the cases. The sigmoid sinus distance at the level of the digastric notch was larger on the right side in 64% of the cases, and the sigmoid sinus distance at the level of the digastric notch to the jugular foramen was larger on the right side in 70% of the cases. Conclusion Significant craniometric differences were found between both sides of the same skulls. .

Objetivo Comparar os lados direito e esquerdo no mesmo crânio nos pontos referenciais descritos e definir as diferenças craniométricas entre ambos. Método Realizamos mensurações em 50 crânios secos de humanos adultos comparando os lados direito e esquerdo. Resultados Como resultado, obtivemos as medidas da largura do seio sigmóideo na altura do ângulo sinodural maiores no lado direito em 78% dos casos e na altura do ponto digástrico em 72%. A largura do forame jugular foi também maior no lado direito em 84% dos casos. A distância do seio sigmóideo na altura do ângulo sinodural até a altura do ponto digástrico foi maior do lado direito em 64% dos casos, e a distância do seio sigmóideo na altura do ponto digástrico até o forame jugular foi maior do lado direito em 70% dos casos. Conclusão Diferenças craniométricas significativas foram encontradas entre os dois lados do crânio. .

Delimitação dos acessos cranianos / Definition of cranial approaches

São descritos os pontos craniométricos e, a partir deles, definidos os pontos referenciais e as linhas para delimitar os principais acessos cranianos: pterional, fronto-orbital, frontobasal, frontal, temporal anterior, parietal, occipital, suboccipital e pontos de punção dos cornos frontal e occipital do ventrículo lateral.

Craniometric points are described, and from them, set the reference points and lines to delimit the main cranial approaches: pterional, fronto-orbital, frontobasal, frontal, anterior temporal, parietal, occipital, suboccipital and points for puncture of the frontal and occipital horns of the lateral ventricles.

The Morphometric Study for the Rolandic Fissure

OBJECTIVE : The purpose of this study was to characterize the Rolandic fissure(Rf) and was to identify the Rf using the surface bony landmarks which can be usually exposed on craniotomy. METHODS : After morphological evaluation of the Rfs using 21 Korean adult formalin fixed cadavers, craniometric measurement was carried out from the surface bony landmarks of nasion, glabella, bregma, and lambda. RESULTS : The Rfs of both hemispheres did not show the mirror image. The Rfs ran forward and downward toward the sylvian fissure keeping the mean angle of 67degrees from mid-sagittal line as elongated S-shape in left and the elongated reverse S-shape in right hemisphere. Connections between the Rf and the longitudinal fissure and between the Rf and the sylvian fissure were found in 3 (7.1%) and 2 (4.8%) of 42 hemispheres, respectively. Most Rfs extended superiorly to 2-3mm lateral to the most superomedial surface of hemispheres and extended inferiorly to 3-5mm superior to the sylvian fissures. The mean distances from the nasion, glabella, bregma, and lambda to the most superomedial aspect of the Rf were 18.8+/-0.9cm, 16.6+/-0.8cm, 5.2+/-0.6cm, and 6.9+/-1.0cm, respectively. The mean distance measured between the Rf and the nasion using traditional method was 18.4+/-0.6cm. CONCLUSION : The distance between the Rf and the nasion roughly correspond within the range of mean 4 mm compared with that measured by the traditional measurement. These data may be more helpful to delineate the Rf after the placement of drapes for craniotomy.