Skull Dimensions Research Articles

Growth and Age Structure in an Introduced and Hunted Cervid Population: White-Tailed Deer in Finland

White-tailed deer were introduced to Finland in 1934 from Minnesota, North America. The population has expanded and is now an important wildlife species, managed through hunting. We determined the age of 451 individuals harvested in the 2012 hunting season. Hunters measured their body mass after slaughter and we measured the dimensions of the lower jaw (in both sexes) as well as skull dimensions and antler scores (in males). The sample indicated a deficit of older males in the population. Females seem to gain their size at the age of two while males continue to increase their body size and that of skeletal traits until the age of four. The size traits measured were similar to those in the North American studies. Based on population growth patterns and introduction history, the white-tailed deer population is performing well in Finland but the potentially skewed sex-specific age distribution warrants further attention.

Comparing methods for estimating cranial capacity in incomplete human fossils using the Jingchuan 1 partial cranium as an example

Cranial capacity is one of the most important features used in hominin taxonomic and morphological analyses. For complete or nearly complete modern human crania, the traditional methods of estimating cranial capacity include filling the vault with seeds, the water displacement method, and the use of regression formulae based on craniometrics. For incomplete human fossils, cranial capacities are estimated by reconstructing endocasts manually or virtually or by using existing modern human skull regression formulae; however, the accuracies of these methods are usually dubious. To find a more accurate way of estimating cranial capacity of partial skulls, seven different estimation methods are compared, including the manual reconstruction of the endocast, models built on skulls and models built on endocasts. We then estimated the cranial capacity of a fragmentary Late Pleistocene cranium, Jingchuan 1. The models are tested on 30 modern human skulls, three Homo erectus fossils and one Late Pleistocene Homo sapiens fossil. In terms of estimating the cranial capacity of the fossil humans, our results indicate that the cranial capacity estimates based on endocasts are more precise than those from exterior skull dimensions, that multivariate models are better than univariate ones, and that the new models using PCR and PLSR have the smallest errors (<50 ml). From the seven methods, the cranial capacity of Jingchuan 1 is estimated to be 1630 ml, 1505 ml, 1533 ml, 1468 ml, 1512 ml, 1470 ml, and 1457 ml, respectively. The most reliable results for the Jingchuan 1 cranial capacity are between 1470 and 1457 ml, and the average is 1464 ml. This study has direct applications to future studies of cranial capacity variation and brain evolution in fossil and modern humans.

An anatomical study of the dorsal and ventral nasal conchal bullae in normal horses: Computed tomographic anatomical and morphometric findings.

Infection of the dorsal nasal conchal bulla and ventral nasal conchal bulla has recently been shown to cause clinical disease in horses, but the anatomy of these 2 structures is poorly documented. To describe the anatomical features, dimensions and relationships to adjacent structures of the dorsal conchal bulla and ventra conchal bulla in normal horses using computed tomography (CT). Descriptive imaging study using cadavers. Computed tomographic images acquired from 60 equine cadaver heads that were shown to be free of sinonasal disease were categorised into 3 age groups (0-5; 6-15; >16 years old). Linear and volumetric measurements and descriptive anatomical assessments of the dorsal conchal bulla and ventral conchal bulla were produced from these CT images and the anatomical relationships between the dorsal conchal bulla and ventral conchal bulla and the adjacent structures, particularly the maxillary cheek teeth, were examined. The associations between bullae dimensions with horse ages and skull dimensions were assessed using linear regression. Mean (range) dorsal conchal bulla measurements were: length 7.5 cm (4.6-14), width 1.9 cm (1.3-2.5), height 2.8 cm (1.8-4), volume 24 cm3 (5.9-50.5). Mean ventral conchal bulla measurements were: length 5.7 cm (2.5-8.5), width 1.6 cm (0.7-2.9), height 2.4 cm (0.8-3.7), volume 15 cm3 (0.4-30). In both dorsal conchal bulla and ventral conchal bulla, there were significant differences in sizes between the different age groups (smaller in younger animals). In the ventral conchal bulla, this was probably related to protrusion of the large dental alveoli of younger horses into the lateral nasal cavity. Measures of bullae size and volume were significantly associated with head size. The anatomical positions (rostro-caudal boundaries) of the dorsal conchal bulla and ventral conchal bulla were closely associated with specific maxillary cheek teeth. Computed tomography was a useful technique to establish the linear and volumetric dimensions of the nasal conchal bullae in normal horses. Both dorsal conchal bulla and ventral conchal bulla sizes increased with animal age. Relatively consistent anatomical relationships were shown between the rostral and caudal limits of the bullae and certain maxillary cheek teeth, which would be of diagnostic value with conventional radiography and act as landmarks in the surgical treatment of nasal bulla disease.

Comparative correlation analysis of cranial capacity

The objectives of this study were to apply craniometric method in assessing skull capacity, determining the distribution of the known skull dimensions (length, width and height) and determining the cranial capacity separately by gender in the total sample and to examine the correlation between the results of cranial capacity in relation to gender and age. The materials used for this study were samples of 120 macerated and degreased skulls, 60 male and 60 female, with a average age of 57.97 years (±SD 18.45). The operating method was the craniometric method. The results showed that gender affects the value of cranial capacity, which was higher in males, whereas the effect of age was not proven statistically significant. The capacity of the skull had highly positive statistic correlation with the width, height and length of the particular. Male’s skulls were on average longer, higher and wider than the female’s skulls. Male’s skulls were on average of larger capacity than the female’s skull. Skull age as a factor had no effect on the value of cranial capacity. The skull length was the most dominant factor in determining the cranial capacity.

Aging-related changes in the skulls of Japanese macaques (&lt;i&gt;Macaca fuscata&lt;/i&gt;)

We investigated aging-related changes in the skulls of Japanese macaques (Macaca fuscata). A total of 145 (70 males, 75 females) skulls from macaques aged 7.0–26.9 years (males) and 7.0–30.7 years (females) were measured for 22 craniometric items. Some skull dimensions increased from young adulthood (7.0 years) to the peak at 13.3–19.0 years in males and at 19.7–22.6 years in females. Some dimensions remained at their peak value right through into very old age whereas others continued increasing during this stage of life. Continued increase of cranial size in adulthood has been also observed in humans, but the magnitude of change was greater in macaques. Facial and mandibular dimensions showed larger and more significant increases than neurocranial dimensions in macaques, as in humans, including facial height, bizygomatic breadth, mandibular body height, and ramus breadth in both sexes. Intertemporal distance and biorbital breadths after 16.0 years of age decreased significantly in males, and cranial and posterior basicranial lengths increased only in males. We suggest that these craniometric changes are associated with the development of the insertion area onto which muscles attach (by accumulation of physical stress). The face and mandible are greatly influenced by tooth loss and/or dental disorders, both of which are evident in humans. In the present study large changes were also found in skulls that had lost several teeth.

Ursus arctos L., 1758 from Bukovynka Cave (W Ukraine) in an overview on the fossil brown bears size variability based on cranial material

Brown bear Ursus arctos is a permanent member of European Middle and Late Pleistocene carnivore assemblages, which shows great body size fluctuation over time. To study this subject we carried out extensive comparison of 37 cranial metric features based on 2954 measurements coming from 263 specimens. In the statistical analyses we included a new complete brown bear calvarium which was found in Bukovynka Cave in Ukraine and dated to postglacial period. The cranial material was divided into male and female sets and classified according to geographic and stratigraphic affiliation of the samples. Analyses revealed clear decrease in many skull dimensions from the Middle Pleistocene specimens through the Late Pleistocene and postglacial to the Holocene skulls. The trend is probably related with general climatic changes during this period. However, Late Pleistocene specimens from Iberian Peninsula were significantly smaller from other Late Pleistocene European skulls or even a bit younger from the Late Glacial and postglacial period for some dimensions. The deviation from the global trend could result from their isolation from other European populations. These conclusions can be drawn both for male and female skulls. The decrease in body size showed that U. arctos is dynamically evolving species. Thus, the size does not seem to be a perfect criterion in determining the biochronological age of the brown bear findings although a general decreasing trend in size with time is clearly visible. The size of brown bear is under the influence of many factors such as great sexual dimorphism, individual and population variability as well as global and local climatic conditions.

THICKNESS OF THE CRANIAL VAULT IN AUSTRALIAN ABORIGINALS

/CONSIDERING the extensive array of measurable characters usually VJ associated with human craniometry it is surprising that studies of thickness of the cranial vault bones are relatively few in number. However, useful data relating to contemporary populations are accumulating to provide an insight into variability of cranial thickness in relation to sex differences and age changes. Following the comprehensive study of sectioned museum material by Todd (1924), recent investigations have been based on radiographie cephalometry, the usual method for measuring dimensions of the skull in the living. Growth changes in the thickness of frontal and parietal bones at various sites have been studied longitudinally on North American whites by Roche (1953), Young (1957), Hansman (1966) and Knott (1969, 1971). Cross-sectional findings are available for Danish males (Stramrud, 1959) and North American blacks and whites (Adeloye, Kattan and Silverman, 1975). In addition, Israel (1968) has commented on the continuing growth in skull thickness of North American white adults.

Afrotropical forest-dwelling mongooses (Mammalia: Herpestidae:Crossarchus) investigated by craniometry and mitochondrial DNA

On the basis of craniometry, the last systematic revision of cusimanses recognized four species distributed from Guinea (Conakry) to the eastern Democratic Republic of the Congo (DRC). Here, we (re)investigated cusimanses including new specimens collected in Benin, in eastern Cameroon (near the Dja River) and in Central African Republic (CAR) where cusimanses were so far presumed to be absent or had been barely sampled. Using craniometry and two mitochondrial DNA fragments (16S rDNA and cytochrome b), we were able to classify most investigated specimens according to the current taxonomy (viz. Crossarchus obscurus, C. platycephalus, C. alexandri and C. ansorgei). Interestingly, all the specimens from CAR clustered unambiguously with Crossarchus alexandri in the DNA-based analyses but exhibited skull dimensions that were distinct from the four recognized species. Our craniometric and mitochondrial DNA analyses offered two valuable complementary viewpoints to characterize cusimanses but were insufficient to provide a firm taxonomic conclusion about the specimens from CAR. Phylogenetic analyses based on mitochondrial DNA suggested that the two sympatric species living on the left bank of the Congo River were sister-species.

Morphometric characteristics of craniofacial features in patients with schizophrenia

Background: High incidence of craniofacial dysmorphology in patients with schizophrenia confirms the developmental disruptions during embryonic period. Anthropometry of head and face can give us several clues regarding the maldevelopment of brain. The aim of this study was to assess various dimensions of skull in Schizophrenics. Methods: One hundred and one (101) male and female patients that have been diagnosed with chronic schizophrenia were selected from a psychiatric hospital and 101 healthy controls, which were mostly the paramedical staff of another hospital, were included in the study. The age for both the groups was between 20 to 60 years. The head length, width and height and coronal, axial and sagittal arc lengths, and also body height and weight and BMI of participants were measured. Results: Mean anthropometric measurements of head length, width and height were 18.92, 14.08 and 12.69 in patients and 18.90, 13.89 and 13.38 centimeter in control, also axial, coronal and sagittal arc lengths were 55.85, 35.21 and 33.00 in patients and 55.70, 34.54 and 32.19 centimeter in control group, respectively. Compared to controls the patients had significantly increased coronal (P< 0.022) and Sagittal (P< 0.001) arc lengths. The patients also showed significantly lesser head height (P< 0.001) as compared with controls. Conclusion: The linear measurements of skull in patients with Schizophrenia do not significantly differ from normal populations and/or have slightly differences. Future studies may investigate whether head can be an anatomical marker for patients with schizophrenia.

How reliable are morphological and anatomical characters to distinguish European wildcats, domestic cats and their hybrids in France?

Phenotypic variation in hybridizing species or subspecies is a prerequisite for allowing conservation ecologists and wildlife managers to identify parental populations and their hybrids in the field. We assessed the reliability of a set of eight morphological (body size and pelage characters) and four anatomical criteria (skull and intestine morphometric measurements) to distinguish between 302 French specimens classified as wildcat, domestic cat or hybrid on the basis of a Bayesian analysis (STRUCTURE) of their multilocus microsatellite genotypes. This aim was achieved by performing a set of multivariate analyses on morphological, anatomical and genetic data sets (Hill and Smith's analysis, co-inertia analysis and discriminant analysis of principal components). Wildcats and domestic cats were very satisfactorily distinguished, even when using simple non-invasive morphological criteria easily usable in the field like the morphology of the tail, dorsal line or flank stripes. Using anatomical instead of morphological characters slightly increased the discriminating power. Many more difficulties arose when we tried to distinguish hybrid specimens from both wildcat and domestic ones. Anatomical characters performed better than morphological ones in recognizing hybrids, but the assignment success rate remained very low, about 31.6% and 1.5%, respectively. Overall, the most discriminating characters were two continuous, derived anatomical characters: the cranial index followed by the intestinal index. Classification of specimens in three classes based on their microsatellite genotypes appeared to be inadequate for identifying hybrid specimens, as hybrid specimens seemed to be distributed along an anatomical continuum. With this observation in mind, we assessed the linear relationships between a proxy of the individual level of hybridization (qik) and the cranial and intestinal indices, respectively. Both relationships were highly significant. The greatest correlation was found with the cranial index (R² = 60.4%). Altogether, our results suggest that future work should be geared towards enhancing the measure of hybridization using more discriminating molecular markers and improving morphometric skull measurements through the use of modern geometric morphometric methods, using landmarks rather than skull dimension.

Testing Adaptive Hypotheses of Convergence with Functional Landscapes: A Case Study of Bone-Cracking Hypercarnivores

Morphological convergence is a well documented phenomenon in mammals, and adaptive explanations are commonly employed to infer similar functions for convergent characteristics. I present a study that adopts aspects of theoretical morphology and engineering optimization to test hypotheses about adaptive convergent evolution. Bone-cracking ecomorphologies in Carnivora were used as a case study. Previous research has shown that skull deepening and widening are major evolutionary patterns in convergent bone-cracking canids and hyaenids. A simple two-dimensional design space, with skull width-to-length and depth-to-length ratios as variables, was used to examine optimized shapes for two functional properties: mechanical advantage (MA) and strain energy (SE). Functionality of theoretical skull shapes was studied using finite element analysis (FEA) and visualized as functional landscapes. The distribution of actual skull shapes in the landscape showed a convergent trend of plesiomorphically low-MA and moderate-SE skulls evolving towards higher-MA and moderate-SE skulls; this is corroborated by FEA of 13 actual specimens. Nevertheless, regions exist in the landscape where high-MA and lower-SE shapes are not represented by existing species; their vacancy is observed even at higher taxonomic levels. Results highlight the interaction of biomechanical and non-biomechanical factors in constraining general skull dimensions to localized functional optima through evolution.

Morphometric analysis of posterior fossa and foramen magnum

Introduction:Configuration and size of the foramen magnum and posterior fossa plays an important role in the pathophysiology of the posterior fossa and craniovertebral junction disorders. This study is aimed to find out various dimensions of the foramen magnum and posterior fossa.Materials and Methods:This is a prospective study of 100 consecutive normal computerized tomography (CT) scans of posterior fossa and 100 dry adult skulls without any bony abnormality. The posterior fossa volume was calculated by abc/2 in method 1 and by advanced work station of CT scan in method 2. Various dimensions of posterior fossa and foramen magnum were also studied.Results:Age ranged from 16 to 89 years with a mean of 51.3 years. Mean height of posterior fossa were 3.01 cm (±0.22) and 3.52 (±0.43) cm in dry skull and CT scan group, respectively (P < 0.0001). Mean volume of posterior fossa were 157.88 (±27.94) cm3 and 159.58 (±25.73) cm3 by method 1 and method 2, respectively (P > 0.05). All the dimensions of posterior fossa and foramen magnum were larger in male as compared to female. Mean anteroposterior (AP), transverse diameter and surface area of the foramen magnum were 3.31 (±0.35) cm, 2.76 (±0.31) cm, and 729.15 (±124.87) mm2, respectively, in CT scan group as compared to 3.41 (±0.29) cm, 2.75 (±0.25) cm, and 747.67 (±108.60) mm2, respectively, in dry skull group.Conclusion:Normal values of posterior fossa and foramen magnum could serve as a future reference. Dry skull dimensions could be different from CT scan measurement. More studies are needed as there could be variations in dimensions in different regions in India

Thickened skull, scoliosis and other skeletal findings in Unverricht–Lundborg disease link cystatin B function to bone metabolism

PurposeUnverricht–Lundborg disease (EPM1) is a rare type of inherited progressive myoclonic epilepsy resulting from mutations in the cystatin B gene, CSTB, which encodes a cysteine cathepsin inhibitor. Cystatin B, cathepsin K, and altered osteoclast bone resorption activity are interconnected in vitro. This study evaluated the skeletal characteristics of patients with EPM1. MethodsSixty-six genetically verified EPM1 patients and 50 healthy controls underwent head MRI. Skull dimensions and regional calvarial thickness was measured perpendicular to each calvarial bone from T1-weighted 3-dimensional images using multiple planar reconstruction tools. All clinical X-ray files of EPM1 patients were collected and reviewed by an experienced radiologist. A total of 337 X-ray studies were analyzed, and non-traumatic structural anomalies, dysplasias and deformities were registered. ResultsEPM1 patients exhibited significant thickening in all measured cranial bones compared to healthy controls. The mean skull thickness was 10.0±2.0mm in EPM1 patients and 7.6±1.2mm in healthy controls (p<0.001). The difference was evident in all age groups and was not explained by former phenytoin use. Observed abnormalities in other skeletal structures in EPM1 patients included thoracic scoliosis (35% of EPM1 patients) and lumbar spine scoliosis (35%), large paranasal sinuses (27%), accessory ossicles of the foot, and arachnodactyly (18%). ConclusionsSkull thickening and an increased prevalence of abnormal findings in skeletal radiographs of patients with EPM1 suggest that this condition is connected to defective cystatin B function. These findings further emphasize the role of cystatin B in bone metabolism in humans.

Temporal Bone Arrangements in Turtles: An Overview

The temporal region of turtles is characterized by significant anatomical diversity. Turtles show a pure anapsid morphotype that exhibits various different marginal reductions known as emarginations. As a result of this diversity, turtles can be taken as a model by which to understand the processes that may have resulted in the highly debated anatomy of the amniote temporal region in general. In this review on almost forgotten literature, I summarize ten potential factors that may act on the skull to shape the temporal region of turtles. These are: (1) phylogenetic constraints, (2) skull weights, (3) type of food, (4) skull dimensions, (5) muscle bulging, (6) ear anatomy and jaw muscle bending mechanisms, (7) extent and nature of muscle attachment sites, (8) internal forces within the jaw adductor chamber, (9) environmental pressure, and (10) neck bending mechanisms. Particular focus is laid on the interrelationship of the jaw musculature and the dermatocranial armour, which were assumed to influence each other to a certain degree. In the literature, cranial dimensions were assumed to influence temporal bone formation within major tetrapod groups. Among these, turtles seem to represent a kind of intermixture, a phenomenon that may be reflected in their specific anatomy. The references presented should be understood as product of the scientific environment in which they developed and the older literature does not always insist current empirical demands. However, the intuitive and creative ideas and the comprehensive anatomical considerations of these authors may inspire future studies in several fields related to this topic.

Size structure of introduced and native populations of sable in Yakutia

Skull dimensions of nine sable populations in Yakutia (n = 1230 ind.) were studied. Differentiation in the size structure between autochthonous left-bank (large skull) and introduced right-bank (small skull) population groups was revealed. Allochthonous groups occupy an intermediate position between the founders (Vitim, Bureya, Kamchatka) and left-bank aboriginals exhibiting morphological trends that lead to the appearance of new forms of the species.

The identity of Myotis punensis (Chiroptera: Vespertilionidae)

Currently twelve species of Myotis Kaup, 1829 (Vespertilionidae: Myotinae) are recognized from South America, with several other named taxa regarded as synonyms, among them Myotis punensis J.A. Allen, 1914. This name was first regarded as a junior synonym of Myotis albescens (É. Geoffroy, 1806) and subsequently of Myotis nigricans (Schinz, 1821). To address the taxonomic status of the holotype of M. punensis, we compared it to all South American species in the genus. The fringe of hairs on the trailing edge of the uropatagium, the fur color, and external and skull dimensions all suggest M. punensis should be treated as a junior synonym of M. albescens

Cranial ontogenetic variability, sex ratio and age structure of the Red fox

Abstract Describing the sex ratio, age structure of the population and ontogenetic variability of Red fox, Vulpes vulpes (Canidae, Carnivora) skull parameters, this study is based on 416 male and 289 female skulls collected in the Czech Republic. The skulls analysed came from feral individuals, that were shot by hunters. The male to female ratio was 1:0.69 regarding the whole population. Individuals younger than one year prevailed in the population (54% males, 48% females were in their first year of life). Four growth patterns of skull dimensions were described. The first group included mainly skull length dimensions (e.g. condylobasal length). They grew rapidly until the sixth month of life, becoming stabilised afterwards. The second group comprised parameters that were stable throughout the life (e.g. cheek tooth rows). Measurements representing the third growth pattern showed continual growth (mainly width dimensions, e.g. zygomatic breadth). Conversely, smaller dimensions of postorbital breadth were observed after the sixth month of life. Postorbital breadth represented the fourth growth pattern. It was concluded, that male and female Red foxes had similar ontogenetic skull development, even though there were some differences, e.g. in jugular breadth, which increased after the age of six months in males unlike in females.

Dynamic morphological changes in the skulls of mice mimicking human Apert syndrome resulting from gain‐of‐function mutation of FGFR2 (P253R)

Apert syndrome is caused mainly by gain-of-function mutations of fibroblast growth factor receptor 2. We have generated a mouse model (Fgfr2(+/P253R)) mimicking human Apert syndrome resulting from fibroblast growth factor receptor 2 Pro253Arg mutation using the knock-in approach. This mouse model in general has the characteristic skull morphology similar to that in humans with Apert syndrome. To characterize the detailed changes of form in the overall skull and its major anatomic structures, euclidean distance matrix analysis was used to quantitatively compare the form and growth difference between the skulls of mutants and their wild-type controls. There were substantial morphological differences between the skulls of mutants and their controls at 4 and 8 weeks of age (P < 0.01). The mutants showed shortened skull dimensions along the rostrocaudal axis, especially in their face. The width of the frontal bone and the distance between the two orbits were broadened mediolaterally. The neurocrania were significantly increased along the dorsoventral axis and slightly increased along the mediolateral axis, and also had anteriorly displayed opisthion along the rostrocaudal axis. Compared with wild-type, the mutant mandible had an anteriorly displaced coronoid process and mandibular condyle along the rostrocaudal axis. We further found that there was catch-up growth in the nasal bone, maxilla, zygomatic bone and some regions of the mandible of the mutant skulls during the 4-8-week interval. The above-mentioned findings further validate the Fgfr2(+/P253R) mouse strain as a good model for human Apert syndrome. The changes in form characterized in this study will help to elucidate the mechanisms through which the Pro253Arg mutation in fibroblast growth factor receptor 2 affects craniofacial development and causes Apert syndrome.

Anatomical and Physiological Changes Associated with a Recent Dietary Shift in the LizardPodarcis sicula

Dietary shifts have played a major role in the evolution of many vertebrates. The idea that the evolution of herbivory is physiologically constrained in squamates is challenged by a number of observations that suggest that at least some lizards can overcome the putative physiological difficulties of herbivory on evolutionary and even ecological timescales. We compared a number of morphological and physiological traits purportedly associated with plant consumption between two island populations of the lacertid lizard Podarcis sicula. Previous studies revealed considerable differences in the amount of plant material consumed between those populations. We continued the investigation of this study system and explored the degree of divergence in morphology (dentition, gut morphology), digestive performance (gut passage time, digestive efficiency), and ecology (endosymbiont density). In addition, we also performed a preliminary analysis of the plasticity of some of these modifications. Our results confirm and expand earlier findings concerning divergence in the morphology of feeding structures between two island populations of P. sicula lizards. In addition to the differences in skull dimensions and the prevalence of cecal valves previously reported, these two recently diverged populations also differ in aspects of their dentition (teeth width) and the lengths of the stomach and small intestine. The plasticity experiment suggests that at least some of the changes associated with a dietary shift toward a higher proportion of plant material may be plastic. Our results also show that these morphological changes effectively translate into differences in digestive performance: the population with the longer digestive tract exhibits longer gut passage time and improved digestive efficiency.

Evaluation of frontal sinus and skull measurements using spiral CT scanning: An aid in unknown person identification

The present study was undertaken to test a simple system for the identification of unknown bodies using spiral CT images of frontal sinus and other skull measurements among selected Iraqi sample. Ninety patients (45 males and 45 females) with age range from 20 to 49 years were selected in this study. Three features and two groups of measurements of frontal sinus and three skull dimensions were obtained from the CT images. Three basic features were F (presence or absence of frontal sinus), S (septum) and S (scalloping). Measurements selected for the study were frontal sinus width, height and anteroposterior length. In addition to measurements of total width, the distance between the highest points of the two sinuses, the distance between the highest points of each sinus to its maximum lateral limit. Skull measurements included; maximum skull length, prostio-bregmatic height and maximum skull width. All data were subjected to a descriptive and discriminative analysis using the SPSS (Version 17.0). The pre-post comparison (number of discordant items) resulted in 95% accurately predicted perfect match for intra-examiner calibration and 90% accurately predicted perfect match for inter-examiners calibration and the result for one discordant item was 5% for intra-examiner calibration and 10% for inter-examiners calibration. The discriminative analysis showed that the ability of the frontal sinus to identify gender was 76.9%, adding the skull measurements to the frontal sinus measurements gave a higher overall classification accuracy for gender (85.9%). Frontal sinus measurements are valuable method in differentiating gender. Adding skull measurements to the frontal sinus measurements can significantly improve accuracy of gender determination using discriminant analysis. CT based films can provide valuable and precise measurements not only for frontal sinus but even for the whole skull that cannot be approached by other means.