Cranial Structures Research Articles

Peculiarities of Early Ontogenesis of Nose Char (N1-form), Endemic Lacustrine and Riverine Form of Salvelinus malma Complex (Salmonidae), of the Lake Kronotskoe (Eastern Kamchatka, Russia)

The growth, order of anlage, and features of transitive stages of skeletal elements (cranial bones and serial structures: teeth, gill rakers, fin rays, pterigyophores, vertebrae muscles, predorsalia, and scales) in were studied in pre-larvae, larvae, and fingerlings of the nose char (N1-form), endemic lakustrine-riverine form of the Dolly varden Salvelinus malma complex of the Lake Kronotskoe, reared in the laboratory at a constant temperature. A comparative analysis of the early ontogenesis of sympatric species of nose char and white char of the Lake Kronotskoe evidences on a high similarity in the growth rate and development of the two forms, differing by the body length of free embryos and the larvae coloration.

Pak1ip1 Loss-of-Function Leads to Cell Cycle Arrest, Loss of Neural Crest Cells, and Craniofacial Abnormalities.

Neural crest cells (NCCs) comprise a transient progenitor cell population of neuroepithelial origin that contributes to a variety of cell types throughout vertebrate embryos including most mesenchymal cells of the cranial and facial structures. Consequently, abnormal NCC development underlies a variety of craniofacial defects including orofacial clefts, which constitute some of the most common birth defects. We previously reported the generation of manta ray (mray) mice that carry a loss-of-function allele of the gene encoding the preribosomal factor Pak1ip1. Here we describe cranioskeletal abnormalities in homozygous mray mutants that arise from a loss of NCCs after their specification. Our results show that the localized loss of cranial NCCs in the developing frontonasal prominences is caused by cell cycle arrest and cell death. In addition, and consistent with deficits in ribosome biosynthesis, homozygous mray mutants display decreased protein biosynthesis, further linking Pak1ip1 to a role in ribosome biogenesis.

Cranial evolution in the extinct Rodrigues Island owl Otus murivorus (Strigidae), associated with unexpected ecological adaptations

Island birds that were victims of anthropic extinctions were often more specialist species, having evolved their most distinctive features in isolation, making the study of fossil insular birds most interesting. Here we studied a fossil cranium of the ‘giant’ extinct scops owl Otus murivorus from Rodrigues Island (Mascarene Islands, southwestern Indian Ocean), to determine any potential unique characters. The fossil and extant strigids were imaged through X-ray microtomography, providing 3D views of external and internal (endocast, inner ear) cranial structures. Geometric morphometrics and analyses of traditional measurements yielded new information about the Rodrigues owl’s evolution and ecology. Otus murivorus exhibits a 2-tier “lag behind” phenomenon for cranium and brain evolution, both being proportionately small relative to increased body size. It also had a much more developed olfactory bulb than congeners, indicating an unexpectedly developed olfactory sense, suggesting a partial food scavenging habit. In addition, O. murivorus had the eyes placed more laterally than O. sunia, the species from which it was derived, probably a side effect of a small brain; rather terrestrial habits; probably relatively fearless behavior; and a less vertical posture (head less upright) than other owls (this in part an allometric effect of size increase). These evolutionary features, added to gigantism and wing reduction, make the extinct Rodrigues owl’s evolution remarkable, and with multiple causes.

Dermal modifications of the red lionfish, Pterois volitans

Vertebrates have evolved flexible and hard dermal armor, but there is often a tradeoff between mobility and protection. Skeletal modifications include fish scales, the shells of tortoises and turtles, and the cranial projections that are found in marine iguanas and lionfish. Sexual dimorphisms of cranial structures are prominent in fishes; we hypothesized that cranial projections of Pterois volitans will change over ontogeny and are sexually dimorphic. The goal of this study is to quantify differences in the cranial armor of P. volitans over a range of sizes (juveniles to adults) to understand allometric growth and possible sexual dimorphisms using specimens from invaded ranges. We found no difference in the total number of cranial spines between sexes, suggesting that the number of cranial spines is not a sexually dimorphic trait in P. volitans. We found positive allometry for total cranial spine number, and length and width of the three largest cranial spines, with respect to the fish total length. Here, we also document another skeletal modification in P. volitans, which is the addition of spines on the caudal fin. Overall, these data show that P. volitans' develop robust dermal modifications as they grow larger, and we suggest that phenotypic plasticity of this species should be explored in their native and invaded ranges.

Technical Note: New similarity index for radiotherapy and medical imaging.

To describe a new similarity index and consider its biomedical applications. Similarity index for a pair of objects is defined by the number of shared features and total number of features in these objects. Similarity measure for more than two objects is commonly defined by using pairwise similarity indices. In the current study we suggest a novel similarity index which depends on the number of features shared between multiple objects and does not have the limitations of the recently described similarity measures. In order to introduce the new index, we consider a concept of "commonality." For a collection of sets , commonality of a given element equals the number of sets this element belongs to. The similarity index for the compared sets is then defined by a weighted sum of normalized commonalities. The considered biomedical applications of the proposed index include comparison of independent delineations of critical cranial structures in MR images and comparison of isodose distributions from different radiotherapy plans. This study describes a novel similarity index which can be used to assess the similarity of multiple independent delineations of the anatomical structure or similarity of multiple dose distributions. Unlike the commonly used pairwise similarity indices, the new index is defined by the number of elements shared between multiple sets. Potential applications of the suggested similarity index for radiotherapy and medical imaging have been described.

Introduction of MOLUMA’S Implant-An Innovation to permanent cure of Trigeminal neuralgia and several Neurovascular compression syndrome

Introduction of MOLUMA’S Implant-An Innovation to permanent cure of Trigeminal neuralgia and several Neurovascular compression syndrome - IJN- Print ISSN No: - 2581-8236 Online ISSN No:- 2581-916X Article DOI No:- 10.18231/j.ijn.2020.021, IP Indian Journal of Neurosciences-IP Indian J Neurosci

Contribution to understanding the evolution of holometaboly: transformation of internal head structures during the metamorphosis in the green lacewing Chrysopa pallens (Neuroptera: Chrysopidae)

BackgroundMetamorphosis remains one of the most complicated and poorly understood processes in insects. This is particularly so for the very dynamic transformations that take place within the pupal sheath of holometabolous insects. Only few studies address these transformations especially with regard to cranial structures of those holometabolous species where the larval and adult forms have a similar diet. It thus remains unclear to what extent the internal structures undergo histolysis and rebuilding. Here, the development of the brain and skeleto-muscular system of the head of Chrysopa pallens (Rambur, 1838) is studied. This species is a predator of aphids in the larval and adult stage.ResultsWe used micro-computed-tomography (μ-CT) to study the transformations of the larval, prepupal and pupal head within the cocoon. We first assessed the morphological differences and similarities between the stages. We then determined the point in time when the compound eyes appear and describe the re-orientation of the head capsule which transforms the prognathous larva into a hypognathous adult. The internal head muscles are distinctly more slender in larvae than adults. In addition, the adults have a significantly larger brain which is likely needed for the processing of the signals obtained by the adults vastly expanded sensory organs that are presumably needed for dispersal and mating. Our study shows that the histolysis and modification of the inner muscles and skeletal elements take place within the prepupa. The central nervous system persists throughout metamorphosis but its morphology changes significantly.ConclusionOur study reveals that not only the inner structures, but also the outer morphology continues to change after the final larval moult. The adult cuticle and internal structures form gradually within the cocoon. The histolysis and rebuilding begin with the skeletal elements and is followed by changes in the central nervous system before it concludes with modifications of the musculature. This order of events is likely ancestral for Holometabola because it is also known from Hymenoptera, Diptera, Mecoptera, and Coleoptera.

Volumetric analysis of the cranial and nasal cavity from micro-computed tomography scans in the rabbit.

The aim of the study was to estimate the volume values of the cranial cavity and nasal cavity structures and to compare the efficiency of manual segmentation of three-dimensional reconstruction and Cavalieri's principle (CP) methodologies. Volume values of the cranial cavity, maxillary sinus (MS), dorsal conchal sinus (DCS), dorsal nasal meatus (DNM), middle nasal meatus (MNM), ventral nasal meatus (VNM), ventral nasal concha (VNC), middle nasal concha (MNC) and nasal vestibule (NV) were estimated with manual segmentation and CP from micro-computed tomography images in 5 male New Zealand white rabbits. Volume measurements and elapsed time were compared with each other. Three-dimensional reconstruction models of nasal and cranial cavity structures were created. There was a statistically significant difference between methods of the MS, DCS, DNM, MNM, VNM, VNC, and MNC volume measurements. Additionally, there was a statistically significant difference between the volumetric analysis time period of the methods and CP was found much shorter than manual segmentation. Realistic results were achieved in a short time with the CP among the stereology methods. It is thought that these image and quantitative data results can be used for modelling, toxicology and pathology studies such as acute and chronić rhinitis or rhino sinusitis as well as a good understanding of the relationship of the anatomical structures in the nasal cavity.

Description of the sagittal jaw relation in cephalometric analysis – a review of literature

Abstract Introductionː Lateral cephalometry is commonly used to analyse craniofacial morphology, soft tissue profile and the direction of facial growth in an attempt to predict the possibilities and limits of orthodontic therapy. The aim of the study was to present the most frequently used cephalometric measurements to assess the skeletal class on a lateral cephalometric headfilm. Materials and methods: A Pubmed search was undertaken to systematize information on ANB angle, WITS appraisal, APDI and Harvold measurements. The keywords used were “cephalometry AND evaluation of sagittal malocclusion AND reference lines AND accuracy OR ANB angle OR WITS appraisal OR APDI”. A manual search was performed from the reference lists of studies found in order to identify and include pioneer studies. Results: A total number of 1258 records were found and finally 23 studies were included in the review. Four of them were descriptive, the other 19 were randomized control trials. Conclusionsː 1. ANB angle cannot be used as the only indicator of sagittal skeletal discrepancy. 2. WITS appraisal is independent of the variability of cranial base structures, thus may be an important supplement to the diagnosis, although it depends on the variability of the occlusal plane. 3. APDI can reliably distinguish between class I, II and III malocclusions.

Correlations of linear sizes of molars with cephalometric indicators of practically healthy men of the northern region of Ukraine

The question of the relationship between the metric characteristics of cranial structures and odontometric parameters, and the possibility of building models based on them, which can later find their practical application in dental practice, remain a pressing problem of modern medical science. The purpose of the study is to establish the features of the relationship between the linear dimensions of molars with the cephalometric parameters of the brain and facial skull of practically healthy men in the northern region of Ukraine. 32 practically healthy residents of the northern region of Ukraine (from Kyiv, Zhytomyr, Sumy and Chernihiv regions) underwent computed tomography followed by odontometry of molars and cephalometry. The correlations between odontometric and cephalometric parameters were assessed using Spearman’s nonparametric statistics in the licensed package “Statistica 6.1”. The peculiarities of the correlations of the studied characteristics of molars with the indicators of the cerebral skull are established – multiple, only direct reliable (r = 0.35-0.57) and unreliable (r = 0.30-0.35) average correlation force (18.7% on the upper jaw, of which the relative majority with vestibular-lingual and mesio-distal dimensions and 24.1% on the lower jaw, of which the relative majority with the height of the teeth, their crowns and the length of the tooth roots); as well as with the indicators of the facial skull – mostly direct reliable (r = 0.35-0.51) and unreliable medium strength (r = 0.30-0.37) correlations, in most cases of a single nature (6.0% on the upper jaw and 6.6% on the lower jaw, almost uniformly with the height of the teeth, their crowns, root length, vestibular-lingual and mesio-distal dimensions). The results of correlation analysis of craniofacial structures are necessary for the correct construction of mathematical models, which can later find their practical application in dental practice and forensic medicine.

Considerações sobre abelisauridae (Dinosauria: Theropoda) e o registro brasileiro

Abelisauridae é uma ampla família de dinossauros do grupo Theropoda, que inclui grandes animais carnívoros extintos bem como as aves dos dias atuais. Sua distribuição é majoritariamente sulista, mas alguns espécimes são oriundos da Europa. As relações filogenéticas dos abelissaurídeos têm se tornado refinadas, mas ainda existem discordâncias quanto ao posicionamento de grupos incluídos na família que merecem atenção. O plano corporal dos abelissaurídeos é conservador entre o grupo, mas apresenta uma grande disparidade morfológica no crânio. Eles também possuem uma tendência a desenvolver estruturas cranianas que variam entre chifres, espessamentos do crânio e coberturas córneas. A variedade de tecido mole craniano associado à estrutura esquelética sugerem que os abelissaurídeos poderiam apresentar comportamentos de marradas de baixo impacto. O registro brasileiro de abelissaurídeos ainda é escasso e são reconhecidas apenas duas espécies em diferentes unidades geológicas. Ainda assim, é possível verificar que a diversidade desse grupo no Brasil foi grande.

Rhinitis: The Osteopathic Modular Approach.

Historically, osteopathic principles have focused on the appropriate drainage of cranial structures to relieve symptoms of rhinitis, which include nasal congestion, anterior/posterior rhinorrhea, sneezing, and itching. Allergic rhinitis is primarily an aberrant immunologic reaction caused by cytokines secreted from lymphocytes that traverse the lymphatic pathway throughout the body. Several studies have documented that, when manipulated, the lymphatic system enhanced the motion of these lymphocytes to important immune structures in both human and animal models. Additionally, modulation of both sympathetic and parasympathetic outflow has been found either to inhibit or enhance secretion and/or drainage of important allergic sites. Osteopathic approaches to rhinitis play an effective role in the comprehensive management of rhinitis, and techniques based on these approaches are therapeutic options for rhinitis. This article provides an up-to-date literature review about the management of rhinitis using the 5 models of osteopathic medicine: biomechanical, respiratory-circulatory, metabolic, neurologic, and behavioral.

The effect of threshold level on bone segmentation of cranial base structures from CT and CBCT images

The use of a single grey intensity threshold is one of the most straightforward and widely used methods to segment cranial base surface models from a 3D radiographic volume. In this study we used thirty Cone Beam Computer Tomography (CBCT) scans from three different machines and ten CT scans of growing individuals to test the effect of thresholding on the subsequently produced anterior cranial base surface models. From each scan, six surface models were generated using a range of voxel intensity thresholds. The models were then superimposed on a manually selected reference surface model, using an iterative closest point algorithm. Multivariate tests showed significant effects of the machine type, threshold value, and superimposition on the spatial position and the form of the created models. For both, CT and CBCT machines, the distance between the models, as well as the variation within each threshold category, was consistently increasing with the magnitude of difference between thresholds. The present findings highlight the importance of accurate anterior cranial base segmentation for reliable assessment of craniofacial morphology through surface superimposition or similar methods that utilize this anatomical structure as reference.

Cranial Base Structures Geometric Morphometry and Description of a Clinical Relevant Anatomical Variation

The foramen magnum is a large median oval opening in the occipital bone in the base of the skull, which leads into the posterior fossa. The foramen magnum has a forwarded shift of its anterior border in humans causing a shortening of the cranial base. The foramen is described as oval, wider posteriorly than anteriorly, and its antero‐posterior diameter exceeds the transversal one. Anteriorly, the margin of the foramen magnum is slightly covered, on each side, by an occipital condyle. These condyles, oval in shape, are located obliquely, so that their anterior end is closer to the median plane. Thirty dry skulls, from adult individuals, present in the anatomy laboratory of our institution were evaluated and a study of the dimensional anatomy of the foramen magnum and the occipital condyles was performed. With the aid of an analog caliper (precision of 0.05mm), the antero‐posterior and transverse diameters of the foramen magnum (posterior to the occipital condyles) and occipital condyles were obtained. Our results showed that the mean antero‐posterior diameter of the foramen magnum was 36.1 ± 0.5 mm and the transverse diameter was 30.0 ± 0.4 mm. The mean antero‐posterior diameter of the right occipital condyle was significantly smaller than that of the left, being 22.2 ± 0.4 mm and 23.1 ± 0.4 mm, respectively. The mean transverse diameter of the right occipital condyle was also statistically smaller than that of the left, being 12.6 ± 0.2 mm and 13.2 ± 0.2 mm, respectively. One of the skulls studied (excluded from the previous statistic) showed anatomical variation in the shape and size of the foramen magnum. This foramen was narrow, with an antero‐posterior diameter of 26.75 mm and a transverse diameter of 22.50 mm. In addition, the occipital condyles were asymmetrical, with the right condyle being practically transverse in relation to the foramen magnum, making a protrusion into its interior, contributing to the transverse narrowing of this foramen. The left condyle presented antero‐posterior (22.95 mm) and transversal (15.95 mm) diameters larger than the right (19.35 mm and 13.10 mm respectively). There were no signs of fractures or previous craniotomies in this particular skull. The present study reports the geometric morphometry of some striking structures at the base of the skull, in addition to describing an important anatomical variation of these structures. We did not find reports of significant difference between the right and left condylar diameters in the literature. The anatomy of the skull base is useful for estimating the race and sex of individuals in forensic medicine. Furthermore, geometric morphometry is an important tool in primatology and anthropology.Support or Funding InformationFAPESP, CNPq, CAPES and FAEPA

Intrauterine and post-ovipositional embryonic development of Amerotyphlops brongersmianus (Vanzolini, 1976) (Serpentes: Typhlopidae) from northeastern Argentina.

The reproductive biology and embryonic development of Typhlopidae have rarely been explored. This family of snakes includes mostly oviparous species with uterine egg retention, but the morphology and development of embryos remain unknown. This work aimed to describe the embryonic development of Amerotyphlops brongersmianus from the northeast of Argentina. For this purpose, embryos from intrauterine eggs of gravid females and eight post-ovipositional eggs incubated in the laboratory were analyzed. Embryonic stages, corresponding to the early, mid and advanced development, and a hatchling were described. The main organs and systems form during the period of intrauterine embryonic retention. Comparing to other snakes, differences in the development of cranial structures such as encephalic vesicles and mandibular and maxillary processes were identified. After oviposition the development and differentiation of the tissues and organs completes, the body scales develop, the characteristic pattern of pigmentation establishes and the embryo grows and consumes the yolk. On average, the incubation period lasts 55 days. Differences in the stage of development at oviposition among females of different populations were observed. Embryonic retention could extend up to advanced stages of development.

Sociodemographic characteristics of patients with chronic headache

Introduction: Headache is an entity characterized by a painful process in the cephalic segment and may originate from cranial or facial structures, being considered a common medical complaint. The chronification process of the pain can present a decrease in quality, the functional capacity and the patient’s and labor environment, and also as well as affect their interpersonal relationships, since the chronic cephalalgic process can lead the patient to moments of social isolation, mood swings, depression. Methods: The research was conducted through a retrospective cross-sectional study, performing the analysis of medical records of patients seen at the Unifacisa’s outpatient neurology School Clinic complaining of chronic headache, from February 1st to August 31, 2019. Results: With the analysis of the medical records, 684 attendances were obtained, where 30 of the patients treated had the diagnosis of chronic headache, 29 women and 01 man. These patients received the following diagnoses: 18 (60%) patients with chronic migraine without aura, 4 (13.3%) patients with chronic migraine with aura, 12 (40%) patients with chronic daily medication overuse headache, 9 (30%) patients with chronic tensiontype headache (CTTH), 1 (3.3%) patient with basilar migraine, 2 (6.6%) patients with secondary headache. Conclusion: Although a small number of chronic headache patients were obtained, yet we realize that it is the migraine that leads to a greater demand for specialized medical care. In addition, as expected due to the latest research, a significant number of patients with headache due to excessive use of common painkillers.

Impact of the endocannabinoid system on murine cranial and alveolar bone phenotype

PurposeThe endocannabionoid signaling system has been demonstrated to be present in the skeleton, with involvement in the regulation of skeletal homeostasis. However, investigations substantiating these findings in cranial and alveolar bones are missing to date. The aim of our study was to investigate a potential impact of the endocannabinoid system on cranial and alveolar bone structures and phenotypes. Basic proceduresCB1-/-, CB2-/- and WT mice (n = 5) were scanned via μCT. Reconstructed datasets were processed for analyses. Cranial cephalometric measurements were performed with OnyxCeph3TMsoftware. Alveolar bone densities were determined via mean grey value measurements with Mimics research 18.0. Alveolar bone heights around teeth in upper and lower jaws were morphometrically analyzed. Alveolar osteoclasts were quantified via TRAP staining of paraffin-embedded histologies. Bone-marrow derived macrophages isolated from murine hind legs were analyzed for CD40 and MMR expression via flow cytometry. Main findingsCB2-/- mice exhibited significantly higher bone densities with mean grey values of 138.3 ± 22.6 compared to 121.9 ± 9.3 for WT for upper jaws, and 134.6 ± 22.9 compared to 116.1 ± 12.9 for WT 134.6 ± 22.9. Concurrently, CB2 receptor knockout entailed reduced alveolar bone heights of about 50% compared to WT mice. Antigen-presenting cell marker expression of MMR was significantly diminished in bone-marrow derived macrophages of CB2-/- mice. Cranium dimensions as much as alveolar osteoclasts were unaffected by receptor knockouts.CB1 receptor knockout did not involve statistically significant alterations in the parameters investigated compared to WT mice. Principal conclusionsThe endoncannabinoid system, and particularly CB2 receptor strongly affects murine alveolar bone phenotypes. These observations suggest CB2 as promising target in the modulation of oral bone phenotypes, probably by impact on bone dynamics via osteal immune cells.

Skull base osteomyelitis: clinical and radiologic analysis of a rare and multifaceted pathological entity.

Skull base osteomyelitis (SBO) is a potentially life-threatening inflammation of cranial base bony structures of variable origin. Criteria for diagnosis and treatment are still controversial. Demographics, predisposing factors, symptoms, imaging, and clinical, laboratory, histological, and microbiological data of patients managed for SBO at the University Hospital of Brescia (ASST Spedali Civili) between 2002 and 2017 were retrospectively reviewed. Patients were included in different etiological groups. The topographic distribution of magnetic resonance (MR) abnormalities was recorded on a bi-dimensional model of skull base, on which three different patterns of inflammatory changes (edematous, solid, or necrotic) were reported. In patients with a history of radiotherapy, the spatial distribution of SBO was compared with irradiation fields. The association between variables and etiological groups was verified with appropriate statistical tests. A classification tree analysis was performed with the aim of inferring a clinical-radiological diagnostic algorithm for SBO. The study included 47 patients, divided into 5 etiological groups: otogenic (n = 5), radio-induced (n = 16), fungal (n = 14), immune-mediated (n = 6), and idiopathic (n = 6). At MR, five types of topographical distribution were identified (central symmetric, central asymmetric, orbital apex, sinonasal, maxillary). In patients with a history of radiotherapy, the probability to develop SBO was significantly increased in areas receiving the highest radiation dosage. The analysis of patients allowed for design of a classification tree for the diagnosis of SBO. The integration of clinical and radiologic information is an efficient strategy to categorize SBO and potentially guide its complex management.

Diagnosis and Treatment of Pituitary Adenomas

Pituitary adenomas are among the most common primary intracranial tumours. They are predominantly benign and account for 10–15 % of all intracranial neoplasms. These tumours are divided into two subgroups: macroadenomas (> 1 cm) and microadenomas (<1 cm). About 30% of pituitary adenomas do not produce hormones. In other cases tumours can produce any of the hormones of the anterior pituitary gland and thus cause endocrine disorders. Compression of the pituitary gland, adjacent cranial nerves and brain structures can lead to gland failure, cranial nerve deficit and other neurological disorders. Visual impairment, usually with bitemporal hemianopia, is one of the most common primary symptoms. Diagnosis of the disease requires an interdisciplinary approach. Transnasal transsphenoidal resection is indicated for all patients with symptomatic pituitary adenomas except prolactinomas. Prolactinomas respond very well to treatment with dopamine agonists. In cases of pituitary insufficiency a timely start of adequate hormone replacement therapy is important. Long-term follow-up is an integral part of the treatment concept. In this review we examine the current diagnostic criteria and treatment methods for various forms of pituitary adenomas.

Clinical Facial Study of the Parents of Children with OAV (Oculo-Auriculo-Vertebral) Syndrome. Cases and Controls

Introduction: The oculo-auriculo-vertebral syndrome is a complex disease of the head and neck. Aim: The purpose of this study was to look for facial asymmetry, measuring both sides of the mandible and external ear in the parents of these patients in a clinical way, to see if it could be considered as a minor manifestation of the disease. Patients and Methods: A clinical, observational study was done with 50 trios and their parents’ controls, at the Instituto Nacional de Rehabilitacion LGII in 2019, from January to May. Mandible and ear measurements were done. Results: All of our patients had microtia and facial asymmetry, and in 17 cases, other anomalies. We compared both sides of the mandible in the patients’ parents and in the parents’ controls. The results showed differences only in the fathers, and in the comparison with the controls, we found statistical differences only in women, family and non-family cases. The ears did not show any differences. Discussion: It is very interesting that we found differences in the measurements of the mandible of the patients’ mothers and their controls; in the mothers the mandible was bigger than in the controls, this probably means that the development of the cranial structures is modified by some genetic variants. No differences were found in the measurements of the ears. Conclusion: It is very difficult to know exactly if the differences we found are important or not. The clinical measurements could be a good option to establish if the parents have minor manifestations that could explain some heritability.