Automatic segmentation and classification of frontal sinuses for sex determination from CBCT scans using a two-stage anatomy-guided attention network.

Sex determination is essential for identifying unidentified individuals, particularly in forensic contexts. Traditional methods for sex determination involve manual measurements of skeletal features on CBCT scans. However, these manual measurements are labor-intensive, time-consuming, and error-prone. The purpose of this study was to automatically and accurately determine sex on a CBCT scan using a two-stage anatomy-guided attention network (SDetNet). SDetNet consisted of a 2D frontal sinus segmentation network (FSNet) and a 3D anatomy-guided attention network (SDNet). FSNet segmented frontal sinus regions in the CBCT images and extracted regions of interest (ROIs) near them. Then, the ROIs were fed into SDNet to predict sex accurately. To improve sex determination performance, we proposed multi-channel inputs (MSIs) and an anatomy-guided attention module (AGAM), which encouraged SDetNet to learn differences in the anatomical context of the frontal sinus between males and females. SDetNet showed superior sex determination performance in the area under the receiver operating characteristic curve, accuracy, Brier score, and specificity compared with the other 3D CNNs. Moreover, the results of ablation studies showed a notable improvement in sex determination with the embedding of both MSI and AGAM. Consequently, SDetNet demonstrated automatic and accurate sex determination by learning the anatomical context information of the frontal sinus on CBCT scans.

Three-Dimensional Volumetric Analysis of Frontal Ethmoidal Cells and Evaluation of Influential Factors: A Helical Computed Tomography Study.

In the present study, we aimed to assess frontal ethmoidal cells by using segmentation 3D software to establish a possible correlation between volume variation and both gender and age, as well as a relationship with Keros classification. Helical computed tomography images were obtained from 71 patients for analysis, in which the agger nasi cell, supra agger cell, supra agger frontal cell, supra bulla frontal cell, supraorbital ethmoidal cell, supra bulla cell, and frontal septal cell were identified and segmented to obtain their volume. Significant differences in volume were found for age and gender regarding agger nasi cells (p-value = 0.017), supra agger cells (p-value < 0.001), and frontal septal cells (p-value = 0.049). In the frontal septal cells, an increase of one year in age reduced the volume by 0.309, on average. According to Keros classification, the mean volumes were 10.07 and 25.64, respectively, for types II and III, both being greater than that of type I. Extracting volumetric data by using segmentation software in agger nasi cells, supra agger cells, and frontal septal cells may be useful for obtaining additional information related to age, in addition to possibly contributing to elucidating the anatomical variations in the region and an identification forensic tool.

Endoscopic management of frontal sinus CSF leaks.

INTRODUCTION: Endoscopic management of frontal sinus cerebrospinal fluid leaks has become the gold standard of treatment, with high success rates and low morbidity. The aim of this study is to review our experience in managing this challenging condition. OBJECTIVE: To review our experience in treating frontal sinus cerebrospinal fluid leaks through an endonasal endoscopic approach. METHODS: A retrospective evaluation of patients undergoing endoscopic surgery for frontal sinus cerebrospinal fluid leaks was performed. Demographics, defect location and etiology, surgical and reconstructive technique, complications, and postoperative followup were examined. RESULTS: Twenty-two patients with a mean age of 40.4 years were treated surgically by the senior author between 2015 and 2019. Cerebrospinal fluid leak was either traumatic (17) or spontaneous (5). Successful first-attempt endoscopic repair was accomplished in all cases. A combined endoscopic-trephination approach was necessary in 5 patients (22.8%). No serious complications were reported, and frontal sinus drainage pathway was patent in all our cases. Revision surgery was necessary in only 2 patients for synechia formation. The mean patient followup was 22.7 months (range: 7 - 41 months). CONCLUSION: Progress in the field of endoscopic surgery has shifted the paradigm, establishing endoscopic repair of frontal sinus leaks as the standard of care. A few remaining limits of this approach could be addressed by combining endoscopy with frontal trephination.

Frontal sinuses as tools for human identification: a systematic review of imaging methods.

The frontal sinuses are potential evidences for human identification because of the inherent distinctiveness of their morphology. Over the last decades, several techniques emerged to enable the visualization and analysis of the frontal sinuses via bi- and three-dimensional imaging. This systematic review aimed to compile different methodological approaches found in the scientific literature to contribute to human identification. Three examiners revisited the scientific literature in order to find imaging techniques for the visualization of the frontal sinuses applied to human identification. The standard search strings built-up from a PICO question identified 404 unique articles in the following databases Medline/Pubmed, Web of Science, Scopus, Lilacs and Scielo. Based on eligibility criteria applied during title, abstract and full-text reading, the sample reduced to 19 articles. The articles were published between 1987 and 2019 by research groups from 10 different countries. Computed tomography was used in 37% of the techniques, while the remaining (63%) techniques used skull radiographs. The techniques were highly heterogeneous and varied between metric analysis, direct image superimposition and morphology code-based systems. The authors considered their techniques useful for human identification and reported accuracy rates from 13 to 100%. Most of the studies revealed low risk of bias. More advantages were related with the techniques based on direct image superimpositions and three-dimensional visualization. Forensic experts must be aware of the use of frontal sinuses for human identification, especially when three-dimensional images are available as ante-mortem and post-mortem evidences for superimposition and comparison.

Sinus computed tomography findings in patients with COVID-19.

OBJECTIVE: To analyze computed tomography scans of paranasal sinuses of a series of patients with coronavirus disease 2019, and correlate the findings with the disease. METHODS: Computed tomography scans of 95 adult patients who underwent a polymerase chain reaction test for severe acute respiratory syndrome coronavirus 2 were analyzed. Clinical data were obtained from patients' records and telephone calls. Paranasal sinus opacification was graded and compared according to severe acute respiratory syndrome coronavirus 2 positivity. RESULTS: Of the patients 28 (29.5%) tested positive for severe acute respiratory syndrome coronavirus 2 (median age 52 [range 26-95] years) and 67 were negative (median age 50 [range 18-95] years). Mucosal thickening was present in 97.4% of maxillary sinuses, 80% of anterior ethmoid air cells, 75.3% of posterior ethmoid air cells, 74.7% of frontal sinuses, and 66.3% of sphenoid sinuses. Minimal or mild mucosal thickening (score 1)and normally aerated sinuses (score 0) corresponded to 71.4% and 21.3% of all paranasal sinuses, respectively. The mean score of each paranasal sinus among severe acute respiratory syndrome coronavirus 2 positive and negative patients was 0.85±0.27 and 0.87±0.38, respectively (p=0.74). Median paranasal sinus opacification score among severe acute respiratory syndrome coronavirus 2 positive patients was 9 (interquartile range 8-10) compared to 9 (interquartile range 5-10) in negative patients (p=0.89). There was no difference in mean score adjusted for age and sex. Nasal congestion was more frequent in severe acute respiratory syndrome coronavirus 2 positive than negative patients (p=0.05). CONCLUSION: Severe acute respiratory syndrome coronavirus 2 infection was associated with patient recall of nasal congestion, but showed no correlation with opacification of paranasal sinuses.

Development and validation of a new formula for sex estimation based on multislice computed tomographic measurements of maxillary and frontal sinuses among Brazilian adults.

OBJECTIVES: To evaluate the accuracy of the measurements of the maxillary sinus (MS) and frontal sinus (FS) in sex estimation among Brazilian adults using multislice computed tomography (MCT) and to develop and cross-validate a new formula for sex estimation. METHODS: The present cross-sectional research was conducted in two phases: (1) development of a formula on the basis of the measurements of both the sinuses (50 males and 50 females); and (2) validation study (20 males and 20 females). The linear measurements (height, width and diameter) were assessed using the RadiAnt DICOM software. A new formula for sex estimation was developed (multivariate statistical approach) and validated. Receiver operating characteristic curves, area under the curve, sensitivity, specificity, positive and negative predictive values, accuracy and likelihood ratio were estimated. RESULTS: Males displayed higher mean values (width, height and diameter) of the FS and MS (p < 0.05). The MS was a better predictor in sex estimation (males vs females), compared to the FS (accuracy between 61-74% and 58-69%, respectively). The distance between the right and left MS displayed the highest accuracy (74%). The sensitivity, specificity and accuracy of the new formula were 80%, 95.5% and 87.5%, respectively. 63.1% reduction was observed in the number of predictive values for sex estimation (individuals older than 30 years). CONCLUSIONS: The present MCT measurements showed a higher accuracy in the estimation of sex in males. The highest accuracy was associated with the distance between the right and left MS. The new formula displayed high precision for sex estimation.

Sinus computed tomography findings in patients with COVID-19 / Achados de imagem em tomografias computadorizadas de seios paranasais em pacientes com COVID-19

ABSTRACT Objective: To analyze computed tomography scans of paranasal sinuses of a series of patients with coronavirus disease 2019, and correlate the findings with the disease. Methods: Computed tomography scans of 95 adult patients who underwent a polymerase chain reaction test for severe acute respiratory syndrome coronavirus 2 were analyzed. Clinical data were obtained from patients' records and telephone calls. Paranasal sinus opacification was graded and compared according to severe acute respiratory syndrome coronavirus 2 positivity. Results: Of the patients 28 (29.5%) tested positive for severe acute respiratory syndrome coronavirus 2 (median age 52 [range 26-95] years) and 67 were negative (median age 50 [range 18-95] years). Mucosal thickening was present in 97.4% of maxillary sinuses, 80% of anterior ethmoid air cells, 75.3% of posterior ethmoid air cells, 74.7% of frontal sinuses, and 66.3% of sphenoid sinuses. Minimal or mild mucosal thickening (score 1)and normally aerated sinuses (score 0) corresponded to 71.4% and 21.3% of all paranasal sinuses, respectively. The mean score of each paranasal sinus among severe acute respiratory syndrome coronavirus 2 positive and negative patients was 0.85±0.27 and 0.87±0.38, respectively (p=0.74). Median paranasal sinus opacification score among severe acute respiratory syndrome coronavirus 2 positive patients was 9 (interquartile range 8-10) compared to 9 (interquartile range 5-10) in negative patients (p=0.89). There was no difference in mean score adjusted for age and sex. Nasal congestion was more frequent in severe acute respiratory syndrome coronavirus 2 positive than negative patients (p=0.05). Conclusion: Severe acute respiratory syndrome coronavirus 2 infection was associated with patient recall of nasal congestion, but showed no correlation with opacification of paranasal sinuses.

RESUMO Objetivo: Analisar imagens de tomografia computadorizada de seios paranasais de pacientes com a doença por coronavírus 2019, e correlacionar os achados com a doença. Métodos: Foram analisadas imagens de tomografia computadorizada de 95 pacientes submetidos a teste de reação em cadeia da polimerase para coronavírus 2 da síndrome respiratória aguda grave. Os dados clínicos foram obtidos por meio dos prontuários dos pacientes e de ligações telefônicas. A opacificação dos seios paranasais foi graduada e comparada entre pacientes positivos e negativos para coronavírus 2 da síndrome respiratória aguda grave. Resultados: Vinte e oito (29,5%) dos pacientes tiveram resultado positivo para coronavírus 2 da síndrome respiratória aguda grave (idade mediana de 52 [26-95] anos) e 67, resultado negativo (idade mediana de 50 [18-95] anos). O espessamento mucoso estava presente em 97,4% dos seios maxilares, 80% das células etmoidais anteriores, 75,3% das células etmoidais posteriores, 74,7% dos seios frontais e em 66,3% dos seios esfenoidais. Mínimo ou discreto espessamento mucoso (pontuação 1) e seios com aeração normal (pontuação 0) corresponderam a 71,4% e 21,3% de todos os seios paranasais, respectivamente. A nota média de cada seio paranasal entre pacientes positivos e negativos para coronavírus 2 da síndrome respiratória aguda grave foi de 0,85±0,27 e 0,87±0,38, respectivamente (p=0,74). A nota mediana de opacificação dos seios paranasais entre pacientes positivos para coronavírus 2 da síndrome respiratória aguda grave foi de 9 (intervalo interquartil de 8 a 10), comparada a 9 (intervalo interquartil de 5 a 10) em pacientes negativos (p=0,89). Não houve diferença na nota média ajustada para idade e sexo. A congestão nasal foi mais frequente em pacientes positivos para coronavírus 2 da síndrome respiratória aguda grave que naqueles com resultados negativos (p=0,05). Conclusão: A infecção pelo coronavírus 2 da síndrome respiratória aguda grave apresentou associação com congestão nasal, mas não mostrou correlação com espessamento mucoso dos seios paranasais.

The incidence of sinus crista galli in children and adults: a computerized tomography study / La incidencia del sinus crista galli en niños y adultos: un estudio de tomografía computarizada

The pneumatization area in the crista galli region of the ethmoid bone can be called Sinus Crista Galli (SCG). The authors would like to recommend the terminology as sinus crista galli for pneumatized crista galli. Our aims in this study are to determine SCG on three dimensional Computerized Tomography (CT) images, to investigate its frequency, dimension and to emphasize their clinical significance in children and adults. A total of 360 adult images (160 female, 200 male) and 68(43 female, 25 male) pediatric images were examined. The presence SCG was recorded with axial and coronal paranasal sinus CT images. The height, width, anterposterior diameter of the sinus was measured. All the data we obtained from this study were analyzed using the SPSS 18.0 program. Descriptive statistics are shown as mean ± Sdt. Sinus crista galli was found in 17 examined images of the 360 (4.72 %) in adult group. Chronic pansinusitis was detected in 7 of 17 cases. Frontal sinusitis findings were detected in 7 cases. Sinusitis was not observed in 3 cases. The incidence of SCG was found in 4 pediatric images out of 68 (5.88 %). In 1 out of 4 cases, infection was detected in SCG. We did not observe SCG in the pediatric group with 0-7 years of age. Sinus crista galli was found at low rates in adult and pediatric age group. However; relationship was found between these variation and chronic rhinosinusitis. Additionally, detection of SCG in paranasal sinus CT can be provided better results and reduce complications in anterior cranial fossa surgery.

El área de neumatización en la crista galli del etmoides se puede denominar sinus crista galli (SCG). Los autores recomiendan incluir en la terminología anatómica el término sinus crista galli para la crista galli neumatizada. Los objetivos del estudio fueron determinar la SCG en imágenes tridimensionales de tomografía computarizada (TC), investigar su frecuencia, dimensión y enfatizar su importancia clínica en niños y adultos. Se examinaron un total de 360 imágenes de adultos (160 mujeres, 200 hombres) y 68 (43 mujeres, 25 hombres) en imágenes pediátricas. La presencia de SCG se registró con imágenes de tomografía axial y axial del seno paranasal. Se midió la altura, anchura y diámetro anteroposterior del seno del proceso crista galli. Todos los datos obtenidos se analizaron mediante el programa SPSS 18.0. Las estadísticas descriptivas se muestran como media ± DS. El seno crista galli se encontró en 17/360 (4,72 %) de las imágenes examinadas en el grupo de adultos. Se detectó pansinusitis crónica en 7 de 17 casos. Se detectaron hallazgos de sinusitis frontal en 7 casos. Sinusitis no se observó en 3 casos. La incidencia de SCG se encontró en 4 imágenes pediátricas de 68 (5,88 %). En 1 de cada 4 casos, se detectó infección en SCG. No observamos SCG en el grupo pediátrico con 0-7 años de edad. El seno crista galli se encontró en bajas tasas en adultos y en niños. Sin embargo, se encontró relación entre estas variaciones y la rinosinusitis crónica. Además, la detección de SCG en la tomografía computarizada del seno paranasal puede proporcionar mejores resultados y reducir las complicaciones en la cirugía de la fosa craneal anterior.

Abordaje endoscópico del seno frontal mediante Draf III: experiencia de la Red de Salud UC Christus / The Draf III procedure as an endoscopic frontal sinus approach: Red de Salud UC Christus' experience

RESUMEN Introducción: El Draf III es una técnica quirúrgica que permite el abordaje endoscópico de los senos frontales. Fue descrita como un procedimiento de rescate para la rinosinusitis crónica (RSCr) frontal en que falla la cirugía estándar. Actualmente, su uso se ha extendido a otras aplicaciones. Objetivo: (1) Revisar las indicaciones del abordaje Draf III, (2) Revisar si el abordaje permitió el manejo adecuado de la patología y (3) Evaluar la permeabilidad de los senos frontales. Material y método: Estudio retrospectivo descriptivo. Se evaluaron los registros de pacientes sometidos a un abordaje Draf III entre los años 2013-2016 (n =11). Se revisaron las indicaciones quirúrgicas, utilidad del Draf III para manejar la patología, permeabilidad de los senos frontales y complicaciones quirúrgicas. Resultados: Indicaciones quirúrgicas incluyeron la RSCr con pólipos, osteoma frontoetmoidal, mucocele frontal, papiloma invertido y estesioneuroblastoma. En todos los casos, el abordaje permitió un adecuado manejo de la patología. Todos los pacientes presentaron permeabilidad adecuada del Draf III al último control. Un paciente debió ser reoperado a los 15,5 meses por recidiva de papiloma invertido. Ningún paciente requirió cirugía de revisión por estenosis crítica del Draf III. No hubo complicaciones quirúrgicas. Discusión: El Draf III fue útil para manejar la RSCr, patologías benignas del seno frontal, y como parte de un abordaje extendido a la fosa craneal anterior. Conclusión: En nuestra serie, el Draf III resultó ser una excelente opción quirúrgica para el tratamiento de diversas patologías del seno frontal.

ABSTRACT Introduction: The Draf III procedure is an effective approach for the management of frontal sinus disorders. It was originally described as a rescue procedure for the treatment of refractory frontal sinusitis. Currently, it can be used to treat a variety of other disorders. Aim: (1) To review the indications for the Draf III procedure, (2) To evaluate if it enabled appropriate management of the disease, and (3) To evaluate frontal sinus patency. Material and Method: Retrospective descriptive study. Clinical records of patients who underwent a Draf III procedure between the years 2013-2016 (n=11) were reviewed. Surgical indications, the appropriateness of the approach to manage the frontal sinus disease, frontal sinus patency, and complications were analyzed. Results: Surgical indications included chronic rhinosinusitis with polyps, frontoethmoidal osteoma, frontal mucocele, inverted papilloma and esthesioneuroblastoma. In all cases, the approach allowed adequate management of the pathology. All patients had adequate patency of the Draf III at their last follow-up. One patient required a revision Draf III at 15.5 months follow-up because of an inverted papilloma recurrence. No patient required revision surgery for critical stenosis of the Draf III. No surgical complications were observed. Discussion: The Draf III procedure was useful for the management of chronic rhinosinusitis, for benign frontal sinus pathologies, and as part of an extended approach to the anterior cranial fossa. Conclusion: In our series, the Draf III procedure was an excellent surgical option for the management of a variety of frontal sinus pathologies.

Giant fronto-ethmoidal osteoma - selection of an optimal surgical procedure / Osteoma fronto-etmoidal gigante - escolha do procedimento cirúrgico ideal

Abstract Introduction Osteomas of the paranasal sinuses are benign bone tumours that produce clinical signs depending on their size and location. In most reported cases large tumours are excised by an external approach or in conjunction with an endoscopic technique. Endoscopic treatment of such tumours is a huge challenge for the operator. Objective Determine the optimal surgical approach by analysing giant osteomas of the frontal and ethmoidal sinuses in the literature. Methods Group of 37 osteomas obtained from the literature review. A group of osteomas removed only by endoscopy was compared with a group in which an external approach (lateral rhynotomy or craniotomy) or combined external and endoscopic approach was applied. Results The authors, based on the statistical analysis of the literature data, have found that the average size of osteomas excised endoscopically and those removed by external approaches does not differ statistically, when the osteomas are located in the ethmoidal cells (p = 0.2691) and the frontal sinuses (p = 0.5891). Conclusion The choice of surgical method appears to be independent of the osteoma size and the decision is likely to be taken based on the experience of the surgeon, available equipment and knowledge of different surgical techniques.

Resumo Introdução Osteomas dos seios paranasais são tumores ósseos benignos cujas manifestações clínicas ocorrem em função de seu tamanho e localização. Na maioria dos casos relatados os tumores grandes são excisados por uma abordagem externa ou associada a uma técnica endoscópica. O tratamento endoscópico destes tumores ainda é um grande desafio para o cirurgião. Objetivo Determinar a abordagem cirúrgica ideal ao analisar osteomas gigantes dos seios frontal e etmoidal na literatura. Método Um total de 38 osteomas foram avaliados a partir da revisão da literatura. Um grupo de osteomas removidos apenas por cirurgia endoscópica foi comparado com um grupo para o qual foi utilizado uma abordagem externa (rinotomia lateral ou craniotomia) ou uma abordagem combinada, externa e endoscópica. Resultados Os autores, com base na análise estatística dos dados da literatura, observaram que o tamanho médio dos osteomas excisados endoscopicamente e daqueles que foram removidos através de uma abordagem externa não diferiram estatisticamente, tanto para osteomas localizados no seio etmoidal (p = 0.2691) quanto para os localizados no seio frontal (p = 0.5891). Conclusão A escolha do método cirúrgico parece ser independente do tamanho do osteoma e a decisão provavelmente será tomada com base na experiência prévia do cirurgião, nos equipamentos disponíveis e conhecimento de diferentes técnicas cirúrgicas.

Giant fronto-ethmoidal osteoma - selection of an optimal surgical procedure.

INTRODUCTION: Osteomas of the paranasal sinuses are benign bone tumours that produce clinical signs depending on their size and location. In most reported cases large tumours are excised by an external approach or in conjunction with an endoscopic technique. Endoscopic treatment of such tumours is a huge challenge for the operator. OBJECTIVE: Determine the optimal surgical approach by analysing giant osteomas of the frontal and ethmoidal sinuses in the literature. METHODS: Group of 37 osteomas obtained from the literature review. A group of osteomas removed only by endoscopy was compared with a group in which an external approach (lateral rhynotomy or craniotomy) or combined external and endoscopic approach was applied. RESULTS: The authors, based on the statistical analysis of the literature data, have found that the average size of osteomas excised endoscopically and those removed by external approaches does not differ statistically, when the osteomas are located in the ethmoidal cells (p=0.2691) and the frontal sinuses (p=0.5891). CONCLUSION: The choice of surgical method appears to be independent of the osteoma size and the decision is likely to be taken based on the experience of the surgeon, available equipment and knowledge of different surgical techniques.

The Frontal Sinus Cavity Exhibits Sexual Dimorphism in 3D Cone-beam CT Images and can be Used for Sex Determination.

Few studies have assessed the use of the frontal sinus cavities for sex differentiation. In this study, a new methodology was used to assess the reliability of CBCT images of the frontal sinus cavity for determining sex based on the sexual dimorphism found in this anatomical structure. The survey sample consisted of 130 scans that were reconstructed three-dimensionally. 3D images of the cavity volume in the frontal, lateral, and basal views were exported in TIFF. The following variables were measured in a second program: area, perimeter, bounding rectangle, ellipse fit, circularity, aspect ratio, roundness, solidity, and Feret's diameter. The methodology demonstrated the existence of sexual dimorphism with an accuracy of 80.0% in the logistic regression model. The basal view had the greatest explanatory power in the final model. This methodology may be used as an alternative way of determining a reliable biological profile during the analysis of skeletal remains.

Manejo endoscópico de osteoma etmoidal con extensión orbitaria: a propósito de un caso / Endoscopic manegement of frontoethmoidal osteoma: on case subject

El osteoma es el tumor más frecuente de los senos paranasales, habitualmente asintomático debido a su lento crecimiento, sin embargo, pueden desarrollarse síntomas dependiendo del tamaño, localización y extensión, con potencial compromiso de órbita y cerebro. La cirugía está indicada en casos sintomáticos pudiendo realizarse abordaje externo, endoscópico o combinado. Presentamos un caso de osteoma etmoidal con compromiso orbitario resuelto, manejado por medio de la cirugía endoscópica nasal, con apoyo de navegación.

The osteoma is the most common tumor of the paranasal sinuses, is usually asymptomatic because of their slow growth, however, may develop symptoms depending on the size, location and extent, with potential compromise of orbit and brain. Surgery is indicated in symptomatic cases, with external, endoscopic or combined approach. We present a case of ethmoidal osteoma with orbital involvement managed by endoscopic image guided surgery.

The possible effects of altitude and climate on the development of the frontal sinus in adults / Los posibles efectos de la altitud y el clima sobre el desarrollo del seno frontal en adultos

Climatic and altitude features of living region may affect human body. Many changes in several tissues and organs and several health problems due to climatic and altitude effects were defined in the literature. However, there were limited number of studies which evaluated correlation between development of frontal sinus and climatic/altitude effect. In this study, widths, heights, AP lengths and volumes of frontal sinus were compared by Paranasal CT scans in populations living in Van which has colder climate and higher altitude and Manisa which has milder climate and lower altitude. It was found that widths, antero-posterior lengths and volumes of frontal sinus were higher in populations living in colder climate and higher altitude according to populations living in milder climate and lower altitude. Heights of frontal sinuses were on the contrary of this. These results were found appropriate to increasing of cephalic index in cold climate according to Allen's Rule. We suggest that larger population study should be made with peoples having the same or similar race and genetic structure in different climate and altitude regions and the proportional comparison of frontal sinus measurements with cephalic index should be considered in future studies.

Las características climáticas y de altitud de una región pueden afectar al cuerpo humano. En la literatura se han identificado muchos cambios en varios tejidos y órganos, como así también numerosos problemas de salud debido a los efectos climáticos y de altitud. Sin embargo, existe un número limitado de estudios que han evaluado la correlación entre el desarrollo del seno frontal y el efecto climático / altitud. En este estudio, los anchos, alturas, longitudes antero-posteriores y volúmenes de seno frontal se compararon mediante tomografía computarizada paranasal en poblaciones que viven en Van, que tiene un clima más frío y mayor altitud, y Manisa, que tiene un clima más suave y menor altitud. Se encontró que los anchos, las longitudes antero-posteriores y los volúmenes de los senos frontales eran mayores en poblaciones que vivían en un clima más frío y de mayor altitud respecto a poblaciones que vivían en clima más suave y con menor altitud. En relación a la altura de los senos frontales, se dio la situación contraria a lo anterior. Estos resultados se encontraron adecuados con el aumento del índice cefálico en la región de clima frío, de acuerdo con la Regla de Allen. Sugerimos que se realice un estudio poblacional más amplio con poblaciones de raza y estructura genética iguales o similares en diferentes regiones climáticas y de altitud. La comparación proporcional de las mediciones de los senos frontales con índice cefálico debería considerarse en futuros estudios.

Frontal Sinus Volume and Frontal Bar Position Are Associated in Unicoronal Craniosynostosis.

BACKGROUND: Frontal sinus pneumatization plays an important role in brow protrusion, and absence of frontal sinus development may be associated with brow retrusion. Using unicoronal craniosynostosis as a model, the authors studied the relationship among frontal sinus volume, supraorbital retrusion, and brow position. METHODS: The authors conducted a retrospective review of unicoronal craniosynostosis patients with head computed tomographic scans and photographs taken from ages 5 to 18 years. Frontal sinus volume and supraorbital retrusion were calculated using three-dimensional computed tomographic reconstructions. A "brow score" from 0 to 3 was assigned to each patient's photographs by a consensus of two craniofacial surgeons; sinus morphology and brow scores were compared. RESULTS: The study included 20 unicoronal craniosynostosis patients. The affected side demonstrated increased retrusion (7.1 ± 3.7 mm versus 3.0 ± 3.1 mm; p < 0.001) and decreased frontal sinus volume (0.8 ± 0.9 cc versus 2.6 ± 1.8 cc; p < 0.001). Qualitative brow retrusion scores differed between affected and unaffected sides (score of 0, 17 percent affected versus 78 percent unaffected; score of 1, 28 percent versus 22 percent; score of 2, 39 percent versus 0 percent; and score of 3, 17 percent versus 0 percent; p < 0.001). Brow scores trended with retrusion measurements (score of 0, 2.7 ± 2.9 mm retrusion; score of 1, 6.1 ± 3.5 mm; score of 2, 8.9 ± 3.2 mm; and score of 3, 9.7 ± 2.8 mm; p < 0.001). Subjects with brow scores of 0 or 1 had larger frontal sinus volumes than subjects with brow scores of 2 or 3 (p = 0.018). CONCLUSIONS: Qualitative brow retrusion correlates strongly with both quantitative supraorbital retrusion and frontal sinus volume. Although this retrospective study cannot prove causality, which is likely multifactorial, its strong correlation with frontal sinus pneumatization highlights the importance of the frontal sinus in brow position in unicoronal craniosynostosis. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Prevalence of agenesis of frontal sinus in human skulls with metopism.

BACKGROUND: The frontal bone is an anatomical structure of the skull separated by the metopic suture in the childhood. The scientific literature indicates that metopic suture consolidates with closure in the early stages of life. Metopism is the term used to describe a metopic suture that persists up to the adulthood. Persistent metopic suture is associated potentially with the agenesis of the frontal sinus. AIM: To investigate the prevalence of absent frontal sinuses in dry skulls with metopism. MATERIALS AND METHODS: The present study was performed after the approval of the local Committee of Ethics in Research. The sample consisted of dry skulls (n=245), aging between 17 and 50 years old, of the Forensic Medical Institute of Goiânia, Brazil. The skulls underwent anthropological exam in the search for metopism. Radiographic exam was performed in the skulls with metopism to verify the presence or absence of the frontal sinus. The radiographic assessment was performed with a Mobile DaRt Evolution device (Shimadzu, Kyoto, Japan) with protocol set in 64 kV and 16 mA). RESULTS: From the 245 dry skulls, 17 presented metopism. The length of the metopic suture in the skulls, considering the distances between nasio and bregma craniometric landmarks, ranged between 114 mm and 137 mm. Radiographic exams were performed on 16 skulls (one skull was not analysed radiographically because of extensive destruction). Only one skull (6.25%) had the frontal sinus absent. Besides the agenesis, the present study also found four (12.5%) skulls with aplasia and eight (25.0%) hyperplasia of the frontal sinus in dry skulls with metopism. CONCLUSION: The present study found a low prevalence rate of the agenesis of frontal sinuses in dry skulls with metopism.