The Morphologicalanalysis Of Pterion In North Indian Population

Pterion is defined as an H-shaped small circular area formed by the junction of four bones: Frontal, Parietal, Temporal and Sphenoid on Norma lateralis of the skull. A 35 dry adult human skulls of unknown sex without any gross pathology or abnormalitywere taken for the study. Sphenoparietal was the commonest type of pterion observed on both the sides. Second most common type of pterion found in our study was stellate type. Stellate type of pterion was present only on right side of skull. The accomplishments of this study contribute to anatomical variations of the pterion, which are of interest to anthropologists, forensic pathologists and surgeons. This topic of study deserves further investigation in other populations from different geographical areas.

Classification and incidence of pterion patterns of Thai skulls / Clasificación e incidencia de los patrones de pterion en cráneos de Tailandia

SUMMARY: The pterion, a landmark for neurosurgery, is the weakest part of the skull owing to relatively thin bone. Variant patterns of pterion can confuse the clinicians during diagnosis of the lateral skull fractures in emergency situations. Thedifferent pterion types of many races have been reported but not of Thais. In this study; therefore, we investigated the incidence of sutural pterion patterns on of Thai skulls. The infratemporal fossa of 110 sides from 55 dried skulls identified as Thais were observed and classified for individual pterion types. The results showed that the pterion patterns can be classified into 4 types; spheno-parietal (87.27 %), fronto-temporal (4.55 %), uni-epipteric (6.36 %), and multi-epipteric (1.82 %) types. It was found that the spheno-parietal type was dominant in males (61.81 %) than in females (25.45 %). The majority of the skulls showed bilateral symmetry (85.45 %) in all types and the unilateral ones were far less (14.55 %). In bilateral pterion incidence, the spheno-parietal type was approximately 93.61 % while the uni-epipteric type was not found. Moreover, the bilateral multi-epipteric type was found only in one female skull (2.13 %). These findings will be useful for the radiologists and the neurosurgeons concerning lateral skull fractures in emergency diagnosis.

RESUMEN: El pterion es un punto de referencia para la neurocirugía, y es la parte más débil del cráneo debido a estar conformado por hueso relativamente delgado. Los diversos patrones de pterion pueden confundir a los clínicos durante el diagnóstico de fracturas laterales de cráneo en situaciones de emergencia. Con excepción de los tailandeses, diferentes tipos de pterion se han reportado en muchas razas. hemos investigado la incidencia de diversos patrones de pterion en cráneos de Tailandia. Analizamos 110 fosas infratemporales, correspondientes a 55 cráneos secos del Noreste de Tailandia y se clasificaron de acuerdo al tipo de pterion. Los resultados mostraron que el pterion puede clasificarse en 4 tipos: esfeno-parietal (87,27 %), fronto-temporal (4,55 %), epiptérico (3,63 %) y multi-epiptérico (1,81 %). Se encontró que el tipo esfeno-parietal tuvo mayor incidencia en hombres (61,81 %) que en mujeres (25,45 %). Además, la incidencia de simetría bilateral (85,45 %) fue mayor que la unilateral (14,55 %). A nivel bilateral, el tipo esfeno-parietal fue de 93,61 %, mientras que el tipo epiptérico no se observó. Por otra parte, el tipo multiepiptérico fue encontrado bilateralmente en un solo cráneo femenino (2,13 %). Esta incidencia puede ser utilizada como un conocimiento básico para los radiólogos tailandeses sobre las fracturas laterales del cráneo en un diagnóstico de emergencia.

Morphological Study on Shapes of Pterion.

Background: Pterion is defined as an H-shaped small circular area formed by the junction of four bones: frontal, parietal, temporal and sphenoid on norma lateralis of the skull, Pterion junction has been used as a common extra-cranial landmark for surgeons in microsurgical and surgical approaches towards important pathologies of this region. Pterion is an important landmark for anterior branch of middle meningeal artery, Broca’s motor speech area to the left, insula, the lateral cerebral fissure, for the pathologies of optic nerve, orbit, sphenoidal ridge and for the anterior circulation aneurysm and tumors, because of its clinical importance we focused our present study on morphology of shape of pterion. Materials and Methods: A total of 500 pterions were examined from 250 adult dry skulls. The present study was undertaken in adult south Indian skulls from different regions of south India, from different medical colleges. We have observed different shapes of pterion like sphenoparietal frontotemporal, stellate and epipteric. Results: The sutural morphology of the pterion and asterion is important in surgical approaches to the cranial fossae. 250 human skulls of known gender (148 male, 102 female) were examined on both sides. Four types of pterion were observed – sphenoparietal 72.8%, frontotemporal 16.4%, stellate 8.8% and epipteric 2%. Conclusion: The pterion is points of sutural confluence seen in the norma lateralis of the skull. The patterns of formation exhibit population based variations. The sutural morphology of the pterion is important in surgical approaches to the cranial fossae. These findings may helpful in surgical approaches and interventions via the pterion.

Morphometric study of pterion in dry human skull bones of nigerians / Estudio morfométrico del pterion en huesos del cráneo humano secos de nigerianos

The pterion is an important landmark on the side of the skull as it overlies both the anterior branch of the middle meningeal artery and the lateral cerebral fissure intracranially. The study was carried out to determine the pterion types and define its distances to some neighboring structures in dry human skulls of Southern Nigerians. The study comprised 50 dry human skulls of unknown sex and age obtained from selected Nigerian Universities. Sutural patterns of the pterion on both sides of each skull based on the description of Murphy (1956), were observed and recorded. Distances of the pterion to neighboring structures were also measured using digital vernial caliper. Data obtained were subjected to statistical analysis using descriptive statistics and chi-square contingency table with the aid of the statistical package for social sciences (SPSS) version 16. P<0.05 is considered statistically significant. Results showed that the most common type of Pterion in Nigerian skulls was sphenoparietal. There was no significant association between side of the head and pterion type. The mean distance of the pterion to the frontozygomatic suture was 31.56±2.47 mm taking both side together, (left side = 31.08±2.24 mm; right side = 32.06±2.62 mm). The mean distance of the pterion to the midpoint of the zygomatic arch was 39.87±3.16 mm taking both sides together (left side = 39.52±3.32 mm; right side = 40.22±2.98 mm). The mean distance of the pterion to the glabella was 77.51±4.08 mm taking both side together (left side = 76.74±4.27 mm; right side = 78.27±3.77 mm). This will be useful in Surgery, Anthropology and for assessing the location of the pterion in incomplete archeological remains or forensic materials.

El pterion es un importante marcador del lado del cráneo, ya que se superpone a la rama anterior de la arteria meníngea media y a la cisura cerebral lateral por vía intracraneal. El estudio se realizó para determinar el tipo de pterion y definir las distancias con algunas estructuras cercanas, en cráneos humanos secos de nigerianos del Sur. Se utilizaron 50 cráneos humanos sin información de sexo y edad, obtenidos de Universidades. Fueron observados y registrados los patrones suturales del pterion en ambos lados de cada cráneo, basados en la descripción de Murphy en 1956. También se midieron las distancias del pterion hacia estructuras cercanas utilizando un cáliper digital. Los datos obtenidos fueron sometidos a análisis estadístico mediante estadística descriptiva y prueba de chi cuadrado con el programa estadístico SPSS versión 16. Un valor P<0,05 se consideró significativo. El tipo más común de pterion en cráneos de Nigeria fue esfenoparietal. No hubo asociación significativa entre el lado del cráneo y el tipo pterion. La distancia media del pterion a la sutura frontocigomática fue 31,56±2,47 mm (al lado izquierdo = 31,08±2,24 mm, al derecho = 32,06±2,62 mm). La distancia media del pterion hasta el punto medio del arco cigomático fue 39,87±3,16 mm (al lado izquierdo = 39,52±3,32 mm; al derecho = 40,22±2,98 mm). La distancia media del pterion a la glabela fue 77,51±4,08 mm (al lado izquierdo = 76,74±4,27 mm, al derecho = 78,27±3,77 mm). Esta información es útil para la cirugía y antropología, así como también en la evaluación de la ubicación del pterion en restos arqueológicos incompletos o material forense.

Surgery of Arterio-Sphenoparietal Sinus Fistula

A 7-month-old boy was presented with growth retardation. The brain CT scan and the cerebral angiography revealed hydrocephalus resulting from venous hypertension and a high-flow direct arteriovenous fistula at the distal M2 segmnt of the middle cerebral artery which was drained into the sphenoparietal sinus. The echocardiogram disclosed a ventricular hypertrophy. The patient was treated by gradual ligation of fistulous portion in ten minutes to prevent sudden increase of peripheral resistance and cardiac overloading. It is stressed that slow obliteration of an arteriovenous fistula is a paramount procedure to prevent congestive heart failure.