Pterion: Morphometry and Surgical Significance

Introduction: Pterion is a H-Shaped formation of sutures and cranio-metric point on the lateral side of skull. It is marked by the junction of frontal, parietal, greater wing of sphenoid & squamous temporal bone. Objective: The study is aimed to determine prevalence of types of pterions, presence of epipteric bone. We also tried to find pterion’s relationship with anterior branch of middle meningeal artery Materials and methods: Study was done in department of Anatomy, GMCH-32, Chandigarh on 40 adult dried skulls without calvaria, of unknown age, gender and race. The skulls with broken lateral wall were excluded. Skulls were examined for 1. A. prevalence of pterion shape B. Prevalence of bilaterality of similar shape of pterion. C. Prevalence of unilateral variation of pterion on two sides of skull. 2. Epipteric bone A. Presence of epipteric bone B. relation to the suture on both sides. 3. Distance of pterion center point to frontozygomatic suture and upper border of zygomatic arch. 4. relationship of pterion on external and internal surface of skull and on inner side its relationship with anterior branch of Middle meningeal artery. Observations: In the present study 3 types of pterions i.e., Sphenoparietal, stellate, frontotemporal were observed. Sphenoparietal was found to be present bilaterally 40% on both sides. Frontotemporal & stellate were 2.5%. Sphenoparietal type of pterion was 55% on right side & 67.5% on left side. frontotemporal type of pterion was 5% on right side & 2.5% on left side, stellate type was 7.5% on right side & 2.5% on left side. epipteric bone were present in pterion on right side in 32.5% & on left side 27.5%. Pterion was lying approximately 3.5 cm above the zygomatic arch and 2.83 cm behind the posterior margin of frontozygomatic suture. Conclusion: in our study the commonest type of pterion shape was Sphenoparietal. This type was most common to be present bilaterally. Epipteric bone was found in Sphenoparietal type both unilaterally & bilaterally. The anterior branch of MMA was closest and farthest in stellate type.

Anatomical variations and morphometric study of pterion in a Thai population associated with clinical implications / Variaciones anatómicas y estudio morfométrico del pterion en una población tailandesa asociada con implicaciones clínicas

SUMMARY: The objective of this study was to consider the type of variation and to estimate the landmarks for localizing the pterion. One hundred twenty Thai dry skulls were selected randomly from the Forensic Osteology Research Center, Faculty of Medicine, Chiang Mai University. The distances of the parameters were measured via Vernier caliper. The sphenoparietal type is the most dominant in the Thai population with 88.75 %. In the male, the distance of the midglabella to the pterion was 9.94?0.64 mm The distance of the frontozygomatic suture to the pterion was 35.41?4.38 mm The distance of the zygomatic arch to the pterion was 39.39?4.69 mm and the distance of the mastoid process tip to the pterion was 86.88?4.44 mm In the female, the distance of the midglabella to the pterion was 9.27?0.63 mm The distance of the frontozygomatic suture to the pterion was 33.08?4.12 mm The distance of the zygomatic arch to the pterion was 33.08?4.12 mm and the distance of the mastoid process tip to the pterion was 83.62?5.16 mm. The pterion approach is the most popular method for neurosurgical procedures, and it provides anatomical variations in the pattern. The sphenoparietal type of pterion is the most common form and the stellate type of pterion is the least common form in Thai skulls. Sex influences the location of the pterion. These findings will be of importance to predict the pterion type in Thai skull and estimate the localization of pterion by using a bony landmark. Knowledge of the precise location of the pterion is an important landmark in the neurosurgical approach.

RESUMEN: El objetivo de este estudio fue considerar el tipo de variación del pterion y estimar los puntos de referencia para localizarlo. Se seleccionaron al azar 120 cráneos secos de individuos tailandeses del Centro de Investigación de Osteología Forense de la Facultad de Medicina de la Universidad de Chiang Mai. Las distancias de los parámetros se midieron mediante un caliper Vernier. El tipo esfenoparietal es el más dominante en la población tailandesa con 88,75 %. En el hombre, la distancia de la glabella al pterion fue de 9,94 ? 0,64 mm. La distancia de la sutura frontocigomática fue de 35,41 ? 4,38 mm La distancia del arco cigomático fue de 39,39 ? 4,69 mm y la distancia del ápice del proceso mastoideo al pterion fue de 86,88 ? 4,44 mm. En la mujer, la distancia de la glabella al pterion fue de 9,27 ? 0,63 mm. La distancia de la sutura frontocigomática al pterion fue de 33,08 ? 4,12 mm. La distancia del arco cigomático al pterion fue de 33,08 ? 4,12 mm y la distancia del ápice proceso mastoideo al pterion fue de 83,62 ? 5,16 mm. El abordaje del pterion es el método más utilizado para procedimientos neuroquirúrgicos y proporciona variaciones anatómicas en el patrón. El tipo esfenoparietal del pterion es la forma más común y el tipo estrellado del pterion es la forma menos común en los cráneos tailandeses. El sexo influye en la ubicación del pterion. Estos hallazgos serán importantes para predecir el tipo de pterion del cráneo en tailandeses y a la vez estimar su localización mediante el uso de un punto de referencia óseo. El conocimiento de la ubicación precisa del pterion es un hito impor- tante en el abordaje neuroquirúrgico.

Morphology of the pterion in Serbian population / Morfología del pterion en población serbia

The pterion is a topographic point on the lateral aspect of the skull where frontal, sphenoid, parietal and temporal bones form the H or K shaped suture. This is an important surgical point for the lesions in anterior and middle cranial fossa. This study was performed on 50 dry skulls from Serbian adult individuals from Department of Anatomy, Faculty of Medicine in Novi Sad. The type of the pterion on both sides of each skull was determined and they are calcified in four types (sphenoparietal, frontotemporal, stellate and epipteric). The distance between the center of the pterion and defined anthropological landmarks were measured using the ImageJ software. Sphenoparietal type is predominant with 86 % in right side and 88 % in left side. In male skulls, the distance from the right pterion to the frontozygomatic suture is 39.89±3.85 mm and 39.67±4.61 mm from the left pterion to the frontozygomatic suture. In female skulls the distance is 37.38±6.38 mm on the right and 35.94±6.46 mm on the left. The shape and the localization of the pterion are important because it is an anatomical landmark and should be used in neurosurgery, traumatology and ophthalmology.

El pterion es un punto topográfico en la cara lateral del cráneo donde los huesos frontales, esfenoides, parietales y temporales forman la sutura en forma de H o K. Este es un punto quirúrgico importante para las lesiones en la fosa craneal anterior y media. Este estudio se realizó en 50 cráneos secos de adultos serbios del Departamento de Anatomía de la Facultad de Medicina de Novi Sad. Se determinó el tipo de pterión en ambos lados de cada cráneo y se calcifican en cuatro tipos (esfenoparietal, frontotemporal, estrellado y epipterico). La distancia entre el centro del pterion y los puntos de referencia antropológicos definidos se midió utilizando el software ImageJ. El tipo esfenoparietal es predominante con 86 % en el lado derecho y 88 % en el lado izquierdo. En los cráneos masculinos, la distancia desde el pterion derecho hasta la sutura frontocigomática es 39,89 ± 3,85 mm y 39,67 ± 4,61 mm desde el pterion izquierdo hasta la sutura frontocigomática. En los cráneos femeninos, la distancia es 37,38 ± 6,38 mm a la derecha y 35,94 ± 6,46 mm a la izquierda. La forma y la localización del pterion son importantes debido a que es un indicador anatómico y debe usarse en neurocirugía, traumatología y oftalmología.

Study of the Location and Morphology of the Pterion in Dry Skulls and Their Clinical Implications

Background: Pterion is usually marked by an H-shaped formof sutures that forms the union of the frontal, parietal, greaterwing of sphenoid, and temporal bones. The center of pterion isaround 4.0 cm higher to the zygomatic arch and 3.0-3.5 cmposterior to frontozygomatic suture. The present study wasconducted with the aim to determine the location of pterion andits clinical implications.Materials and Methods: The present study was conducted inthe Department of Anatomy, Mahatma Gandhi Medical College& Hospital, Jaipur, Rajasthan, India. The study included 40skulls of unknown gender. PT was taken as the distance fromthe center of Pterion to the superior part of thetemporozygomatic suture. For the linear measurements, onejaw of caliper pointed at the frontozygomatic suture and theother at the pterion center. All the data thus obtained wasarranged in a tabulated form and analyzed using SPSSsoftware. Mean and median values of all the results werecalculated.Results: A total of 40 skulls were studied in the present study.The mean distance on the right side was 3.5 cm and on leftside was 3.6 cm with variation between 2.1 To 4.4 cm on bothsides. The median distance on the right side was 3.46 cm andon the left side was 3.48 cm.Conclusion: The location and the type of pterion variesamongst different ethnic and racial groups. The present studymay be of use to the forensic experts and anthropologists.

Sutural Bones: A Study On Incidence, Laterality And Co-relation With Cephalic Index In Dry Crania Of East Indian Ethnicity

Background: Sutural bones are supranumary bones occurring along the sutures and completely surrounded bysutures of the skull. Their number, morphology and location in skull vary in skulls. The knowledge of these bonesis imperative in surgery, medicolegal cases involving child abuse or fracture of skulls and for anthropologicidentification of human populations. This study was undertaken to examine incidence and pattern of distributionof sutural bones in dry skulls from Eastern India and compare the findings with similar studies across the world.Materials and Method: 180 dry crania were identified as male or female skulls and studied for the incidence andpattern of distribution of sutural bones. Also the Cephalic Index was measured for finding its correlation withthe number of sutural bones appearing in a skull.Results: 124 skulls were identified as male and 56 as female skulls. Overall incidence of sutural bone occurrencewas found to be 72.28% which was essentially similar across sexes. The most common sites for sutural bones,in descending order of occurrence, were found to be parieto-occipital suture, asterion, pterion and lambda.Bregma was the least common site where no sutural bone was encountered. A highly statistically significantfinding was in regard to laterality of sutural bone occurrence. Sutural bones occurring along coronal, parietotemporal, parieto-mastoid, occipito-mastoid sutures and pterion exhibited more than 80% tendency towardsunilateral occurrence while those occurring at asterion exhibited around 70% tendency towards unilateraloccurrence. All these findings, although displayed variable degree of sexual dimorphism, were statisticallyinsignificant for variation among sexes. No correlation between the number of sutural bones with cephalic indexwas found.Conclusion: The findings of this study are in agreement with the findings of many similar suitably poweredstudies across the world.

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.

Morphometric Analysis Of Pterion In Adult Human Dry Skull Of Gujarat Region

Background: Pterion is an area present on anterior part of floor of temporal fossa, formed by four bones frontal,parietal, squamous temporal and greater wing of sphenoid joined each other and form ‘H’ shaped suture. Thereare important neurovascular structure lies beneath the pterion. It is weakest area of skull, as the bones here arevery thin so it is more prone to fracture by traumatic blow over it or by indirect blow from top or back of head.Pterion is an important extracranial landmark for lateral or pterional approaches in various neurosurgicalprocedures.Objectives: The aim of this study was to observe various types of pterion and to determine exact location ofpterion from various bony landmarks like Frontozygomatic suture and zygomatic arch.Materials and methods: The present study was carried out on 326 adult human dry skulls collected from variousmedical colleges of Gujarat. The lateral side of skull was visually assessed for the various types of pterion as perMurphy’s classification. The measurements were carried out from center of pterion to superior edges of midpointzygomatic arch (PMPZ) and from center of pterion to posterolateral aspect of frontozygomatic suture (PFZS).Measurements were taken using a digital vernier caliper.Results: We found all four types of pterion in our study. The most common type of pterion is Sphenoparietal 523(80.21%), followed by Epipteric 71 (10.89%), Frontotemporal 34 (5.22%) and Stellate 24 (3.68%). The meandistance of PMPZ was 36.85 ± 3.61 mm and PFZS was 29.69 ± 3.91. The Mean & SD of PMPZ & PFZS on right sidewas little more as compared to left side.Conclusion: The knowledge of various types of the pterion and exact location of center of pterion from variousbony landmarks are important not only to anatomist but also important for neurosurgeon for pterional approachesin various neurovascular surgery, for radiologist to accurate interpretation of radiograph, CT & MRI of skull andfor anthropologist to racial comparison.

Reappraising the neurosurgical significance of the pterion location, morphology, and its relationship to optic canal and sphenoid ridge and neurosurgical implications / 대한해부학회지

Microsurgical treatment of large parasellar meningiomas by pterional craniotomy: A clinical experience with 34 cases / 第二军医大学学报

Objective To introduce the microsurgery treatment method for large parasellar meningiomas by pterional craniotomy and its curative effect. Methods The clinical data of 34 patients with large parasellar meningiomas, who underwent microsurgery via pterional or extensive pterional craniotomy in Seventh People’s Hospital of Shanghai University of Traditional Chinese Medicine Jul. 2006 to Aug. 2016, were retrospectively analyzed. The patients included 13 men and 21 women with ages ranging from 21 to 72 (average, 49±13) years old. The course of disease ranged from 1 to 55 (average, 13±10) months. Maximum diameter of tumors ranged from 3.3 to 5.2 (average, [4.3±0.6]) cm. Results No surgical death occurred in this study. Postoperatively, the cranial imaging examination showed that 24 of 34 cases were totally removed, 5 cases were subtotally removed, and 5 cases were partially removed. The postoperative follow-up time was 24-48 (average, 36±13) months. Twenty-eight cases had good prognoses with Karnofsky score being 80 to 100, and six cases had fair prognoses with Karnofsky score being 60 to 79. Five cases had postoperative oculomotor paralysis, which was improved with nutritional nerve treatment. Conclusion The microsurgical treatment via pterional or extensive pterional craniotomy can improve the total resection rate of the large parasellar meningiomas. Palliative operations combined with postoperative radiotherapy may be employed for the tumors that can only be subtotally and partially removed.

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.

Superficial Temporal Artery-Sparing Mini-Pterional Approach for Cerebral Aneurysm Surgery

OBJECTIVE: The purposes of this study were to introduce a superficial temporal artery (STA)-sparing mini-pterional approach for the treatment of cerebral aneurysms and review the surgical results of this approach. METHODS: Between June 2010 and December 2015, we performed the STA-sparing mini-pterional approach for 117 patients with 141 unruptured intracranial aneurysms. We analyzed demographic, radiologic, and clinical variables including age, sex, craniotomy size, aneurysm location, height of STA bifurcation, and postoperative complications. RESULTS: The mean age of patients was 58.4 years. The height of STA bifurcation from the superior border of the zygomatic arch was 20.5 mm±10.0 (standard deviation [SD]). The craniotomy size was 1051.6 mm²±206.5 (SD). Aneurysm neck clipping was possible in all cases. Intradural anterior clinoidectomy was performed in four cases. Contralateral approaches to aneurysms were adopted for four cases. Surgery-related complications occurred in two cases. Permanent morbidity occurred in one case. CONCLUSION: Our STA-sparing mini-pterional approach for surgical treatment of cerebral aneurysms is easy to learn and has the advantages of small incision, STA sparing, and a relatively wide surgical field. It may be a good alternative to the conventional pterional approach for treating cerebral aneurysms.

A Study on the Occurrence of Wormian Bones Among the Male and Female Skulls of Tamil Nadu. India.

Background: Wormian bones, also known as intra sutural bones are extra bone pieces that occur within a suture in the cranium. These are irregular isolated bones which appear in addition to the usual centers of ossification of the cranium and, although unusual, are not rare. The number of sutural bones varies considerably because different individuals and different population have different numbers of sutural bones. They occur mostly along the sutures and meeting point of the cranial sutures. They occur most frequently in the course of the lambdoid suture. They are also occasionally seen within the sagittal and coronal sutures. Materials and Methods: In this present study we analyzed the occurrence of sutural bones among 50 male and female skulls in Tamil Nadu region and we compared the results along with the studies of Indian skulls. Result and Conclusion: Based on the study we concluded that sutural bones are more among male skulls than in females among the skulls of Tamil Nadu and this is exactly the opposite of the results given in Indian population.

Morphometric Study of Pterion in Adult Dry Skulls in Dakshina Kannada District, Karnataka State, India.

Introduction: The objectives of the present study were to determine the type of the pterion in the dry human skulls of Dakshina Kannada district of Southern India and to study its topography. Materials and Methods: The present study included 32 adult human skulls of unknown gender. The pterions of both the right and left sides were studied. Results: The present study observed all the 4 types of pterion. Among them, Spheno-parietal type was higher in frequency. This type was found on right side 25 (78.1%) and left side 28 (87.5%) skulls. The distance between the centres of pterion to the midpoint of zygomatic arch (P-ZA) was 40.08±0.46 mm on the right side of the skull, whereas on left side of the skull it was 39.9±0.17 mm. Distance between the centre of pterion to the posterolateral aspect of fronto-zygomatic suture (P-FZ) on right side of the skull was 30.37±0.44 mm and it was 29.53±0.26 mm on the left side. Conclusion: We believe that the present study has provided the additional information about the morphology and morphometry of pterion, which is important to the neurosurgical and radiological literature.

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.

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.

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.

A Textiloma on the Pterion : A Rarely Occurred Craniotomy Complication

Textiloma is an inflammatory mass containing surgical sponges that are unintentionally left behind in a surgical wound. This complication has been most commonly described by abdominal and gynecologic surgeons. However, the occurrence of textiloma after intracranial procedures especially under the temporalis muscle has not been documented. The author reports a rare case of textiloma of the pterion in a patient who presented with a subcutaneous tumor developed eight years after frontotemporal craniotomy for aneurysm clipping.

Study of pterion and incidence of epipteric bones in dry human skulls of Gujarat.

Background: Pterion is present in floor of temporal fossa which is a meeting point of four bones, frontal and parietal bone superiorly and the greater wing of sphenoid and squamous temporal bone inferiorly. It is ‘H-shaped’ in most of the skulls. The most common variation is in its shape and presence of epipteric bone. Aim : To report the various types of pterion and incidence of epipteric bones in the human skulls and to compare with other racial groups from previous study. Methods: The present study was conducted using 311 dry, grossly normal human skulls from sources in Gujarat. Different types of pterion and the presence of epipteric bones were observed. Results: In the present study sphenoparietal variety of pterion was predominant and the incidence of epipteric bone was 11.73%. Conclusion: Knowledge of the presence of epipteric bones are important to prevent complications during burr hole surgery and to prevent misdiagnosis of fracture skull at the site of pterion.

Morphometric study of pterion in dry skull of Gujarat Region.

The pterion is a commonly used landmark on neurocranium; classified in four types: sphenoparietal, frontotemporal, stellate and epipteric. In this study we have found out morphology and location of pterion of skull of Gujarat region and comparison of their morphology with other populations. 42 skulls of unknown gender were examined on both sides from Department of Anatomy, Medical College Bhavnagar. Measurements of the location of the pterion were made by using stainless steel callipers. Sphenoparietal was the most common form comprising 91.7%. Measurements between from center of pterion to posterior end of frontozygomatic suture, vertical distance to upper margin of zygomatic arch, horizontal distance to lateral margin of optic canal and horizontal distance to outer end of the sphenoid ridge on the lesser wing of the sphenoid were taken. Anatomical variations of the pterion, which are of interest to anthropologists, forensic pathologists and surgeons, deserve further investigation in other populations from different areas.

Microsurgical removal of suprasellar craniopharyngioma via pterional approach / 中国基层医药

Objective To explore the microsurgical techniques for total removal of the suprasellar cranio pharyngiomas via the pterional approach.Methods The clinical data of 28 patients with suprasellar craniopharyngio mas resected by the microsurgery was analyzed retrospectively.Results The tumors were total removed in 24 cases (86%)and subtotal resected in 4 cases(14%).The frequent postoperative complications are diabetes insipidus,hy perthermy,imbalance of water and electrolyte and lower level of hormone.Conclusion It is the key to get fine operation effect that removal sclerotin of base of skull as far as possible and releasing cerebrospinal fluid sufficiently,paying attention to protect the perforating branch and nourishing artery in each operative spaces.