RESUMO

This study explores the efficacy of texture analysis by using preoperative multi-slice spiral computed tomography (MSCT) to non-invasively determine the grade of cellular differentiation in head and neck squamous cell carcinoma (HNSCC). In a retrospective study, MSCT scans of patients with HNSCC were analyzed and classified based on its histological grade as moderately differentiated, well-differentiated, or poorly differentiated. The location of the tumor was categorized as either in the bone or in soft tissues. Segmentation of the lesion areas was conducted, followed by texture analysis. Eleven GLCM parameters across five different distances were calculated. Median values and correlations of texture parameters were examined in relation to tumor differentiation grade by using Spearman's correlation coefficient and Kruskal-Wallis and Dunn tests. Forty-six patients were included, predominantly female (87%), with a mean age of 66.7 years. Texture analysis revealed significant parameter correlations with histopathological grades of tumor differentiation. The study identified no significant age correlation with tumor differentiation, which underscores the potential of texture analysis as an age-independent biomarker. The strong correlations between texture parameters and histopathological grades support the integration of this technique into the clinical decision-making process.

RESUMO

OBJECTIVES: This study aimed to assess the morphological differences in the articular disc (AD) between hemophilic patients and healthy individuals of the control group for further association with signs and symptoms. METHODS: Fourteen severe hemophilic patients had their AD evaluated by magnetic resonance imaging (MRI). The morphological findings were compared to those of a control group consisting of 14 healthy individuals. MRI was used to evaluate all the components of the temporomandibular (TMJ), including the AD, resulting in sequential T1-weighted parasagittal images. All the images were acquired with teeth in maximum intercuspation position. RESULTS: Morphological alterations showed significant statistical differences (P-value = 0.0068), whereas no statistical differences were found in the other variables, including TMJ pain, headache, bruxism and mouth opening limitation. In the group of non-hemophilic individuals, only two (14.29%) presented AD with non-biconcave features, whereas in the group of hemophilic patients, nine (64.29%) presented AD with a morphology other than biconcave. CONCLUSIONS: In patients with severe hemophilia, there seems to be a pattern of morphological alterations in the articular disc over time. The standard biconcave morphology of AD tends to change into other ones, particularly biplanar, hemiconvex and folded.

Assuntos

RESUMO

OBJECTIVE: Texture analysis is an image processing method that aims to assess the distribution of gray-level intensity and spatial organization of the pixels in the image. The purpose of this study was to investigate whether the texture analysis applied to cone beam computed tomography (CBCT) images could detect variation in the condyle trabecular bone of individuals from different age groups and genders. METHODS: The sample consisted of imaging exams from 63 individuals divided into three groups according to age groups of 03-13, 14-24 and 25-34. For texture analysis, the MaZda® software was used to extract the following parameters: second angular momentum, contrast, correlation, sum of squares, inverse difference moment, sum entropy and entropy. Statistical analysis was performed using Mann-Whitney test for gender and Kruskal-Wallis test for age (P = 5%). RESULTS: No statistically significant differences were found between age groups for any of the parameters. Males had lower values for the parameter correlation than those of females (P < 0.05). CONCLUSION: Texture analysis proved to be useful to discriminate mandibular condyle trabecular bone between genders.

Assuntos

RESUMO

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.

Assuntos

RESUMO

Abstract Objective: Oral Squamous Cell Carcinoma (OSCC) is conventionally treated by surgical resection, and positive surgical margins strongly increase local recurrence and decrease survival. This study aimed to evaluate whether a Three-Dimensional Segmentation (3DS) image of OSCC confers advantage over Multiplanar Reconstruction (MPR) of OSCC using images of computed tomography scan in surgical planning of tumor resection. Methods: Twenty-six patients with locally advanced OSCC had tumor morphology and dimensions evaluated by MPR images, 3DS images, and Surgical Pathology Specimen (SPS) analyses (gold standard). OSCC resection was performed with curative intent using only MPR images. Results: OSCC morphology was more accurately assessed by 3DS than by MPR images. Similar OSCC volumes and dimensions were obtained when MPR images, 3DS images and SPS measurements were considered. Nevertheless, there was a strong correlation between the OSCC longest axis measured by 3DS and SPS analyses (ICC = 0.82; 95% CI 0.59-0.92), whereas only a moderate correlation was observed between the longest axis of OSCC measured by MPR images and SPS analyses (ICC = 0.51; 95% CI 0.09-0.78). Taking only SPS with positive margins into account, MPR images and 3DS images underestimated the tumor's longest axis in eight out of 11 (72.7%) and 5 out of the 11 (45.5%) cases, respectively. Conclusion: Our data present preliminary evidence that 3DS model represents a useful tool for surgical planning of OSCC resection, but confirmation in a larger cohort of patients is required. Level of evidence: Laboratory study.

RESUMO

The differentiation between ameloblastoma (AB) and odontogenic keratocyst (OKC) is essential for the formulation of the surgical plan, especially considering the biological behavior of these two pathological entities. Therefore, developing means to increase the accuracy of the diagnostic process is extremely important for a safe treatment. The aim of this study was to use magnetic resonance imaging (MRI) based on texture analysis (TA) as an aid in differentiating AB from OKC. This study comprised 18 patients; eight patients with AB and ten with OKC. All diagnoses were determined through incisional biopsy and later through histological examination of the surgical specimen. MRI was performed using a 3 T scanner with a neurovascular coil according to a specific protocol. All images were exported to segmentation software in which the volume of interest (VOI) was determined by a radiologist, who was blind to the histopathological results. Next, the textural parameters were computed by using the MATLAB software. Spearman's correlation coefficient was used to assess the correlation between texture parameters and the selected variables. Differences in TA parameters were compared between AB and OKC by using the Mann-Whitney test. Mann-Whitney test showed a statistically significant difference between AB and OKC for the parameters entropy (P = 0.033) and sum average (P = 0.033). MRI texture analysis has the potential to discriminate between AB and OKC as a noninvasive method. MRI texture analysis can be an additional tool to differentiate ameloblastoma from odontogenic keratocyst.

Assuntos

RESUMO

OBJECTIVE: Oral Squamous Cell Carcinoma (OSCC) is conventionally treated by surgical resection, and positive surgical margins strongly increase local recurrence and decrease survival. This study aimed to evaluate whether a Three-Dimensional Segmentation (3DS) image of OSCC confers advantage over Multiplanar Reconstruction (MPR) of OSCC using images of computed tomography scan in surgical planning of tumor resection. METHODS: Twenty-six patients with locally advanced OSCC had tumor morphology and dimensions evaluated by MPR images, 3DS images, and Surgical Pathology Specimen (SPS) analyses (gold standard). OSCC resection was performed with curative intent using only MPR images. RESULTS: OSCC morphology was more accurately assessed by 3DS than by MPR images. Similar OSCC volumes and dimensions were obtained when MPR images, 3DS images and SPS measurements were considered. Nevertheless, there was a strong correlation between the OSCC longest axis measured by 3DS and SPS analyses (ICC = 0.82; 95% CI 0.59‒0.92), whereas only a moderate correlation was observed between the longest axis of OSCC measured by MPR images and SPS analyses (ICC = 0.51; 95% CI 0.09‒0.78). Taking only SPS with positive margins into account, MPR images and 3DS images underestimated the tumor's longest axis in eight out of 11 (72.7%) and 5 out of the 11 (45.5%) cases, respectively. CONCLUSION: Our data present preliminary evidence that 3DS model represents a useful tool for surgical planning of OSCC resection, but confirmation in a larger cohort of patients is required. LEVEL OF EVIDENCE: Laboratory study.

Assuntos

RESUMO

A hemofilia é uma doença hemorrágica hereditária ligada ao cromossomo X, decorrente da ausência ou da baixa quantidade no plasma dos fatores de coagulação VIII (hemofilia A) ou IX (hemofilia B). Clinicamente, a hemofilia se caracteriza por episódios recorrentes de sangramentos, que podem ocorrer espontaneamente ou em decorrência de traumas. O sistema músculo-esquelético é freqüentemente afetado pelos eventos hemorrágicos nos indivíduos portadores de hemofilia. Dentro desse sistema, as articulações são alvos de episódios recorrentes de sangramentos, resultando no fenômeno a que chamamos de hemartrose, responsável por estimular a hiperplasia da membrana sinovial articular e caracterizando o quadro das sinovites hemofílicas. O ciclo vicioso típico de hemartrose-sinovite-hemartrose quando estabelecido, tem como consequência a cronificação das alterações agudas articulares. Histologicamente, na sinovite, é observada a proliferação de fibroblastos sinoviais e a presença de um infiltrado de células inflamatórias. Apesar de a articulação temporomandibular (ATM) ser uma articulação do tipo sinovial, são poucos os relatos sobre o seu envolvimento na hemartrose e na sinovite hemofílica. Em razão disso, o objetivo deste estudo foi o de avaliar a ATM por meio de imagens de ressonância magnética (RM) utilizando-se a técnica denominada relaxometria. A relaxometria, também chamada de mapeamento T2, consiste em calcular as variações na intensidade do sinal de radiofrequência (RF) emitido pelos prótons das moléculas de água em função da variação do tempo quando excitados por um pulso externo de RF e submetidos à influência de um campo magnético estático. Esta mensuração é possível de ser realizada por meio da chamada sequência multieco de spin. A literatura científica descreve que a concentração de ferro nos tecidos resulta em encurtamento do tempo T2 e em consequente diminuição da intensidade de sinal das amostras biológicas. Desta forma, a relaxometria realizada com o objetivo de quantificar a concentração de ferro pode servir como uma forma de se estudar as propriedades intrínsecas dos tecidos e o ambiente molecular das estruturas analisadas. Foram selecionados pacientes maiores de 18 anos de idade, comprovadamente portadores de hemofilia A ou B classificadas como grave e que tiveram seguimento regular ambulatorial. O grupo controle foi pareado por idade e sexo com os pacientes, sendo representado por voluntários sem histórico de discrasia sanguínea ou disfunção temporomandibular (DTM). Foram avaliados 39 indivíduos (18 pacientes e 21 controles). Os critérios de exclusão foram: pacientes portadores de próteses metálicas, marca-passo cardíaco, clipes metálicos intracranianos (para aneurisma), claustrofobia severa e não consentimento à participação no estudo. Este estudo observou que a morfologia dos discos articulares se altera com o passar do tempo em indivíduos portadores de hemofilia grave (p-valor = 0,006), entretanto, nenhuma diferença estatística foi observada no que diz respeito à intensidade de sinal calculada em 4 momentos distintos (p-valor > 0,05), sugerindo não haver uma concentração maior de ferro no interior do disco articular na amostra estudada, nem entre os grupos e nem na transição entre os momentos avaliados. Também não foi observada diferença estatística (p-valor > 0,05) no que diz respeito aos sintomas relatados (sintomatologia dolorosa, cefaleia e alteração no movimento de abertura bucal e lateralidade da mandíbula) entre indivíduos portadores de hemofilia e indivíduos do grupo controle, sugerindo que a ATM possui uma forte capacidade de adaptação em comparação com as demais articulações do tipo sinovial diante dos efeitos provocados pela degradação da cartilagem articular.

Assuntos

RESUMO

Objective: The purpose of the present investigation was to assess whether possible changes in the dynamic movements of the TMJ might cause a greater variation between the volumes of the upper airways in open- and closed-mouth positions.Methods: CBCT scans of 92 subjects were used to assess the TMJ bilaterally. All scans were acquired in closed (CM) and maximum mouth opening (MMO) positions. The difference in the volume of the oropharyngeal cavity obtained by subtracting the CM volume from the MMO volume (delta volume or volume variation) was calculated. The resulting volume was analyzed by Mann-Whitney test for variation in rotation.Results: A significant difference was found (p-value = 0.0188) on the right side regarding changes in the rotational movement of the condyle (Mann-Whitney test).Conclusion: This study showed a relationship between degree of abnormal or limited rotation and variation in the upper airway volume on one side.

RESUMO

Objective: Forensic dentistry has used some methods for the human identification process. However, there is a need to study characteristics that are able to perform identification more specifically, increasing accuracy. Considering the role of dental arch assessment in prediction of gender and ethnicity, the purpose of this study was to assess the volume of pulp chamber as a mean to obtain new forensic evidence. Material and methods: For this task, 1.190 cone beam computed tomography (CBCT) images were retrospectively selected and subdivided according to the population number, gender, age and ethnicity. All DICOM files were imported to the open-source software ITK-SNAP®(http://www.itksnap.org/pmwiki/pmwiki.php). The segmentation process was performed in all pulp chamber aiming to obtain pulp tissue ́s volume. Results: As a result, the pulp chamber volume of mandibular canine teeth showed to be larger in white population than in non-white (P-value = 0.003) and in male individuals in comparison with female (P-value = 0.038). Conclusion: These results, however, must be confirmed by future studies with a larger sample size and by the assessment of other variables, including texture analysis and density of dental tissues. (AU)

Objetivo: A odontologia forense tem usado alguns métodos para o processo de identificação humana. Porém, há a necessidade de estudar características que consigam de forma mais específica realizar a identificação aumentando a precisão. Considerando o papel da avaliação da arcada dentária na predição de gênero e etnia, o objetivo deste estudo foi avaliar o volume da câmara pulpar mandibular como meio de obtenção de novas evidências periciais. Material e métodos: Foram selecionadas 1.190 imagens de tomografia computadorizada de feixe cônico (TCFC) e subdivididas de acordo com o número da população, sexo, idade e etnia. Todos os arquivos em formato DICOM foram importados para o software de código aberto ITK-SNAP® (http://www.itksnap.org/pmwiki/pmwiki.php) onde o processo de segmentação foi realizado em todas as câmaras pulpares visando a obtenção da volumetria. Resultados: Como resultado, o volume da câmara pulpar dos caninos inferiores mostrou-se maior na população branca do que na não branca (P-valor = 0,003), no sexo masculino em comparação ao feminino (P-valor = 0,038). Conclusão: Esses resultados, entretanto, devem ser confirmados por estudos futuros com maior tamanho amostral e pela avaliação de outras variáveis, incluindo análise de textura e densidade dos tecidos dentários. (AU)

Assuntos