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1.
Rev. ADM ; 81(4): 220-224, jul.-ago. 2024. ilus
Article in Spanish | LILACS | ID: biblio-1572789

ABSTRACT

Introducción: el alargamiento de corona relacionado con la estética tiene como objetivo revelar una longitud adecuada de la corona y disminuir la exposición gingival. El procedimiento incluye gingivectomía y alveolectomía para restablecer el tejido gingival supracrestal requerido protésicamente según la dimensión fisiológica. Mediante un escaneo intraoral del maxilar, mandíbula y posición intercuspídea máxima y utilizando un software especializado, se diseña de manera digital la forma de los dientes y el contorno gingival. Este diseño genera una imagen de la restauración estética deseada para el prostodoncista y periodoncista. La fabricación física del diseño es asistida por computadora (CAD-CAM), creando una guía quirúrgica de resina acrílica moldeada al vacío para determinar la longitud de la corona clínica requerida en la cirugía. Objetivo: el caso interdisciplinario presentado describe una técnica innovadora empleando el flujo digital mediante un software que, a partir de un escaneo oral, diseña de manera digital un Mock-Up utilizado como guía para la cirugía periodontal. Presentación del caso: acude a clínica de la Maestría en Periodoncia de la Universidad Autónoma de Coahuila (UAdeC) paciente de 52 años, ASA I, para una cirugía periodontal con fines estéticos. Se procedió a la cirugía, colocando el Mock-Up en la región anterosuperior como guía para la gingivectomía. Luego, se realizó el levantamiento de colgajo antes de la alveolectomía, tomando en cuenta la longitud del tejido gingival supracrestal. Por último, se suturaron los tejidos blandos con técnica de colchonero horizontal. Resultados: siete días después, se retiran los puntos apreciando una cicatrización correcta y uniforme de los tejidos. Conclusiones: este abordaje digital ofrece una reducción significativa del tiempo quirúrgico, además de una estética satisfactoria y una precisa arquitectura gingival (AU)


Introduction: crown lengthening for aesthetic purposes aims to reveal an adequate crown length and reduce gingival exposure. The procedure includes gingivectomy and alveolectomy to restore the prosthetically required supracrestal gingival tissue according to physiological dimensions. Through an intraoral scan of the maxilla, mandible, and maximum intercuspidal position, and using specialized software, the shape of the teeth and the gingival contour are digitally designed. This design generates an image of the desired aesthetic restoration for the prosthodontist and periodontist. The physical fabrication of the design is computer-assisted (CAD-CAM), creating a vacuum-formed acrylic resin surgical guide to determine the clinical crown length required in surgery. Objective: the presented interdisciplinary case describes an innovative technique using digital workflow through software that, from an oral scan, digitally designs a Mock-Up used as a guide for periodontal surgery. Case presentation: a 52-year-old ASA I patient attended the Periodontics Master's clinic at Universidad Autónoma de Coahuila (UAdeC) for periodontal surgery with aesthetic purposes. The surgery was performed by placing the Mock-Up in the anterosuperior region as a guide for gingivectomy. Then, a flap was raised before the alveolectomy, considering the length of the supracrestal gingival tissue. Finally, the soft tissues were sutured with a horizontal mattress suture technique. Results: seven days later, the sutures were removed, showing correct and uniform tissue healing. Conclusions: this digital approach offers a significant reduction in surgical time, in addition to satisfactory esthetics and precise gingival architecture (AU)


Subject(s)
Humans , Male , Middle Aged , Image Processing, Computer-Assisted/methods , Crown Lengthening , Computer-Aided Design , Imaging, Three-Dimensional/methods , Esthetics, Dental , Schools, Dental , Gingivectomy/methods , Mexico
2.
J. oral res. (Impresa) ; 13(1): 15-25, mayo 29, 2024. ilus, tab
Article in English | LILACS | ID: biblio-1563133

ABSTRACT

Aim: This study aimed to collect evidence on the validity and reliability of measurements obtained from digital impression techniques. Materials and Methods: This comparative study was conducted on 31 patients. Intraoral scanner was applied to all patients. For each patient, an alginate impression of the upper maxilla was taken and later the 3D digital model was extracted by dental cone-beam computed tomography (CBCT). For preparation of plaster models, alginate impressions were taken and immediately poured with dental stone. In the next stage, a comparison was performed among the intraoral scanner, CBCT, and plaster models in terms of tooth size, dental width, and intra-arch dimensions. Results: Measuring tooth size and intra-arch dimensions in digital images obtained from intraoral scanner and CBCT were in most cases lower than the results obtained in the plaster models but the differences between digital techniques and plaster models are not clinically noticeable. Conclusions: Digital systems including intraoral scanner and CBCT are acceptable for clinical use in terms of accuracy.


Objetivo: Este estudio tuvo como objetivo recopilar evidencia sobre la validez y confiabilidad de las mediciones obtenidas a partir de técnicas de impresión digital. Materiales y Métodos: Este estudio comparativo se realizó en 31 pacientes. A todos los pacientes se les aplicó escáner intraoral. Para cada paciente, se tomó una impresión de alginato del maxilar superior y posteriormente se extrajo el modelo digital 3D mediante Tomografía computarizada de haz cónico (CBCT) dental. Para la preparación de los modelos de yeso se tomaron impresiones de alginato y se vertieron inmediatamente con yeso dental. En la siguiente etapa, se realizó una comparación entre el escáner intraoral, CBCT y los modelos de yeso en términos de tamaño de diente, ancho dental y dimensiones intraarcada. Discusión: Se encontró que la apariencia microscópica de las células fusiformes era comparable en ambos grupos. Los resultados de la citometría de flujo demostraron expresiones comparables en ambos grupos, siendo las muestras positivas para CD90, CD73, CD105, HLA ABC y negativas para CD34, CD45 y HLA DR. Hubo variaciones en la expresión de los marcadores cuando se evaluaron los potenciales de diferenciación. Conclusión: Los sistemas digitales como el escáner intraoral y el CBCT son aceptables para uso clínico en términos de precisión.


Subject(s)
Humans , Tooth/anatomy & histology , Image Interpretation, Computer-Assisted/methods , Casts, Surgical , Mandible/anatomy & histology , Imaging, Three-Dimensional/methods , Cone-Beam Computed Tomography , Flow Cytometry , Iran/epidemiology
3.
Chin. med. j ; Chin. med. j;(24): 329-337, 2024.
Article in English | WPRIM | ID: wpr-1007634

ABSTRACT

BACKGROUND@#Pathological scars are a disorder that can lead to various cosmetic, psychological, and functional problems, and no effective assessment methods are currently available. Assessment and treatment of pathological scars are based on cutaneous manifestations. A two-photon microscope (TPM) with the potential for real-time non-invasive assessment may help determine the under-surface pathophysiological conditions in vivo . This study used a portable handheld TPM to image epidermal cells and dermal collagen structures in pathological scars and normal skin in vivo to evaluate the effectiveness of treatment in scar patients.@*METHODS@#Fifteen patients with pathological scars and three healthy controls were recruited. Imaging was performed using a portable handheld TPM. Five indexes were extracted from two dimensional (2D) and three dimensional (3D) perspectives, including collagen depth, dermo-epidermal junction (DEJ) contour ratio, thickness, orientation, and occupation (proportion of collagen fibers in the field of view) of collagen. Two depth-dependent indexes were computed through the 3D second harmonic generation image and three morphology-related indexes from the 2D images. We assessed index differences between scar and normal skin and changes before and after treatment.@*RESULTS@#Pathological scars and normal skin differed markedly regarding the epidermal morphological structure and the spectral characteristics of collagen fibers. Five indexes were employed to distinguish between normal skin and scar tissue. Statistically significant differences were found in average depth ( t = 9.917, P <0.001), thickness ( t = 4.037, P <0.001), occupation ( t = 2.169, P <0.050), orientation of collagen ( t = 3.669, P <0.001), and the DEJ contour ratio ( t = 5.105, P <0.001).@*CONCLUSIONS@#Use of portable handheld TPM can distinguish collagen from skin tissues; thus, it is more suitable for scar imaging than reflectance confocal microscopy. Thus, a TPM may be an auxiliary tool for scar treatment selection and assessing treatment efficacy.


Subject(s)
Humans , Cicatrix/diagnostic imaging , Skin/pathology , Collagen , Imaging, Three-Dimensional/methods
4.
Rev. Fac. Odontol. (B.Aires) ; 39(91): 41-48, 2024. ilus
Article in Spanish | LILACS | ID: biblio-1554951

ABSTRACT

La microtomografía es un estudio que utiliza la ra-diación X para obtener imágenes de tamaños de mi-lésimas de milímetros y de alta resolución. Las imá-genes 2D son procesadas por diferentes softwares para lograr obtener volúmenes capaces de ser ana-lizados tridimensionalmente. La microtomografía es el estudio de elección a la hora de evaluar caracte-rísticas muy pequeñas con gran precisión. La obtu-ración endodóntica buscar lograr un sellado que no tenga espacios vacíos dentro de la masa de obtura-ción. Esto es importante debido a que los poros pue-den permitir, si están en contacto con la pared den-tinaria, la entrada de microorganismos al conducto radicular. El objetivo de este trabajo fue describir el procedimiento para el análisis y visualización de los espacios vacíos dentro de la obturación endodónti-ca, utilizando la microtomografía de rayos x, y esta-blecer un protocolo para ser utilizado por cualquier investigador(AU)


Microtomography is a study that uses X-radiation to obtain high-resolution images of sizes of thousandths of millimeters. The 2D images are processed by different software to obtain volumes capable of being analyzed three-dimensionally. Microtomography is the study of choice when evaluating very small features with great precision. Endodontic filling seeks to achieve a seal that does not have voids within the filling obturation. This is important because the voids can allow, if they are in contact with the dentin wall, the entry of microorganisms into the root canal. The objective of this work was to describe the procedure for the analysis and visualization of voids within the endodontic filling using microtomography and to establish the protocol to be used by any researcher (AU)


Subject(s)
Root Canal Obturation/adverse effects , Clinical Protocols , X-Ray Microtomography/methods , Porosity , Imaging, Three-Dimensional/methods , Dental Leakage/prevention & control
5.
Article in Spanish | LILACS, CUMED | ID: biblio-1536331

ABSTRACT

Para afrontar la reciente emergencia global por COVID-19, la comunidad científica y los profesionales de la salud en Cuba trabajan constantemente en el desarrollo de nuevos tratamientos y tecnologías que posibiliten el diagnóstico precoz de esta enfermedad, todo ello para facilitar el manejo general de esta pandemia.1) De ahí que se requiere el perfeccionamiento continuo de este proceso en correspondencia con los principios de la medicina, con una formación humanista, científica y con una visión integral de los problemas de salud como elemento esencial que caracteriza la formación de profesionales de la salud en territorio cubano donde la especialidad de Medicina General Integral constituye la principal disciplina integradora de contenidos, para ofrecer una atención preventiva, sistemática y continua al paciente a lo largo del tiempo, donde el médico en formación sea expresión de sus cualidades humanas. Coherente con esto, en 1984 se inició en Cuba la formación de especialistas en Medicina General Integral (MGI). Esta especialidad no tenía antecedentes en el país, por lo cual su propuesta constituye el perfeccionamiento del enfoque social de la medicina, que desde su implantación es la premisa básica del sistema de salud cubano. La formación de estos profesionales ocurre en la propia comunidad, con una alta calidad en los servicios que se brindan a la población.2 Para cumplir con esta función...(AU)


Subject(s)
Humans , Male , Female , Imaging, Three-Dimensional/methods , COVID-19/epidemiology , Cuba
6.
Int. j. morphol ; 41(2): 401-409, abr. 2023. ilus, tab, graf
Article in English | LILACS | ID: biblio-1440294

ABSTRACT

SUMMARY: Hyoid bone measurements have been proposed to vary between different genders and age groups. The aim of the study is to study hyoid morphometrics among Jordanian patients. 3D-CT scans of 637 patients were analyzed. Ten parameters of hyoid bone were measures, including the anteroposterior length, length of greater horns (right and left), height of greater horns (right and left), width of hyoid body, height of hyoid body, the distance between the midpoints of the posterior ends of the greater horns of the hyoid bone, the angle between right and left greater horns, and the distance of the hyoid bone to the vertebral column. Also, vertebral level, fusion rank, morphology of hyoid body lingula, and shape of hyoid bone were documented. All hyoid dimensions were longer in males, but greater horns angle was wider in females. In patients younger than 30 years, the parameters are the smallest with the widest angle. The distance from hyoid to vertebral column is higher in males (30-49) years of age. No fusion between hyoid body and greater horns was observed in patients younger than 10 years, but fusion (unilateral or bilateral) was found in only 73.2 % of patients ≥ 70 years. The hyoid was mostly at vertebra C3 level and "U" shaped. The lingula shape was mostly "Scar" in males (especially ≥ 50 years) and "Nothing" in females (especially < 50 years). The maximum growth of hyoid dimensions is before age of 30 years. Fusion between hyoid body and greater horns was not seen in patients younger than 10 years. Otherwise, the hyoid features failed to predict age or gender in our sample. Furthermore, 3D-CT scan is an excellent tool to assess the anatomy of head and neck region.


Se ha propuesto que las medidas del hueso hioides varían entre los diferentes sexos y grupos de edad. El objetivo del estudio fur estudiar la morfometría del hueso hioides en pacientes jordanos. Se analizaron tomografías computarizadas en 3D de 637 pacientes. Se midieron diez parámetros del hueso hioides, incluyendo la longitud anteroposterior, la longitud de los cuernos mayores (derecho e izquierdo), la altura de los cuernos mayores (derecho e izquierdo), el ancho del cuerpo hioides, la altura del cuerpo hioides, la distancia entre los puntos medios de los extremos posteriores de los cuernos mayores del hueso hioides, el ángulo entre los cuernos mayores derecho e izquierdo, y la distancia del hueso hioides a la columna vertebral. Además, se documentaron el nivel vertebral, el rango de fusión, la morfología de la língula del cuerpo hioides y la forma del hueso hioides. Todas las dimensiones del hioides fueron más largas en los hombres, pero el mayor ángulo de los cuernos fue más ancho en las mujeres. En pacientes menores de 30 años, los parámetros son los más pequeños con el ángulo más amplio. La distancia del hioides a la columna vertebral es mayor en el sexo masculino (30-49) años. No se observó fusión entre el cuerpo hioides y los cuernos mayores en pacientes menores de 10 años, pero se encontró fusión (unilateral o bilateral) en solo el 73,2 % de los pacientes ≥ 70 años. El hioides estaba mayormente al nivel de la vértebra C3 y en forma de "U". La forma de la língula era mayoritariamente "Cicatriz" en los hombres (especialmente ≥ 50 años) y "Nada" en las mujeres (especialmente < 50 años). El máximo crecimiento de las dimensiones del hioides es antes de los 30 años. La fusión entre el cuerpo hioides y los cuernos mayores no se observó en pacientes menores de 10 años. No obstante, las características del hueso hioides no pudieron predecir la edad o el sexo en nuestra muestra. Además, la tomografía computarizada 3D es una herramienta excelente para evaluar la anatomía de la región de la cabeza y el cuello.


Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Aged , Young Adult , Tomography, X-Ray Computed/methods , Imaging, Three-Dimensional/methods , Hyoid Bone/diagnostic imaging , Sex Factors , Age Factors , Hyoid Bone/anatomy & histology
7.
Chinese Journal of Stomatology ; (12): 519-526, 2023.
Article in Chinese | WPRIM | ID: wpr-986104

ABSTRACT

In light of the increasing digitalization of dentistry, the automatic determination of three-dimensional (3D) craniomaxillofacial features has become a development trend. 3D craniomaxillofacial landmarks and symmetry reference plane determination algorithm based on point clouds has attracted a lot of attention, for point clouds are the basis for virtual surgery design and facial asymmetry analysis, which play a key role in craniomaxillofacial surgery and orthodontic treatment design. Based on the studies of our team and national and international literatures, this article presented the deep geometry learning algorithm to determine landmarks and symmetry reference plane based on 3D craniomaxillofacial point clouds. In order to provide reference for future clinical application, we describe the development and latest research in this field, and analyze and discuss the advantages and limitations of various methods.


Subject(s)
Humans , Imaging, Three-Dimensional/methods , Facial Asymmetry , Algorithms
8.
Chinese Journal of Stomatology ; (12): 554-560, 2023.
Article in Chinese | WPRIM | ID: wpr-986110

ABSTRACT

Objective: To explore an automatic landmarking method for anatomical landmarks in the three-dimensional (3D) data of the maxillary complex and preliminarily evaluate its reproducibility and accuracy. Methods: From June 2021 to December 2022, spiral CT data of 31 patients with relatively normal craniofacial morphology were selected from those who visited the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology. The sample included 15 males and 16 females, with the age of (33.3±8.3) years. The maxillary complex was reconstructed in 3D using Mimics software, and the resulting 3D data of the maxillary complex was mesh-refined using Geomagic software. Two attending physicians and one associate chief physician manually landmarked the 31 maxillary complex datasets, determining 24 anatomical landmarks. The average values of the three expert landmarking results were used as the expert-defined landmarks. One case that conformed to the average 3D morphological characteristics of healthy individuals' craniofacial bones was selected as the template data, while the remaining 30 cases were used as target data. The open-source MeshMonk program (a non-rigid registration algorithm) was used to perform an initial alignment of the template and target data based on 4 landmarks (nasion, left and right zygomatic arch prominence, and anterior nasal spine). The template data was then deformed to the shape of the target data using a non-rigid registration algorithm, resulting in the deformed template data. Based on the unchanged index property of homonymous landmarks before and after deformation of the template data, the coordinates of each landmark in the deformed template data were automatically retrieved as the automatic landmarking coordinates of the homonymous landmarks in the target data, thus completing the automatic landmarking process. The automatic landmarking process for the 30 target data was repeated three times. The root-mean-square distance (RMSD) of the dense corresponding point pairs (approximately 25 000 pairs) between the deformed template data and the target data was calculated as the deformation error of the non-rigid registration algorithm, and the intra-class correlation coefficient (ICC) of the deformation error in the three repetitions was analyzed. The linear distances between the automatic landmarking results and the expert-defined landmarks for the 24 anatomical landmarks were calculated as the automatic landmarking errors, and the ICC values of the 3D coordinates in the three automatic landmarking repetitions were analyzed. Results: The average three-dimensional deviation (RMSD) between the deformed template data and the corresponding target data for the 30 cases was (0.70±0.09) mm, with an ICC value of 1.00 for the deformation error in the three repetitions of the non-rigid registration algorithm. The average automatic landmarking error for the 24 anatomical landmarks was (1.86±0.30) mm, with the smallest error at the anterior nasal spine (0.65±0.24) mm and the largest error at the left oribital (3.27±2.28) mm. The ICC values for the 3D coordinates in the three automatic landmarking repetitions were all 1.00. Conclusions: This study established an automatic landmarking method for three-dimensional data of the maxillary complex based on a non-rigid registration algorithm. The accuracy and repeatability of this method for landmarking normal maxillary complex 3D data were relatively good.


Subject(s)
Male , Female , Humans , Adult , Imaging, Three-Dimensional/methods , Reproducibility of Results , Algorithms , Software , Tomography, Spiral Computed , Anatomic Landmarks/anatomy & histology
9.
J. biomed. eng ; Sheng wu yi xue gong cheng xue za zhi;(6): 1168-1174, 2023.
Article in Chinese | WPRIM | ID: wpr-1008947

ABSTRACT

Reconstructing three-dimensional (3D) models from two-dimensional (2D) images is necessary for preoperative planning and the customization of joint prostheses. However, the traditional statistical modeling reconstruction shows a low accuracy due to limited 3D characteristics and information loss. In this study, we proposed a new method to reconstruct the 3D models of femoral images by combining a statistical shape model with Laplacian surface deformation, which greatly improved the accuracy of the reconstruction. In this method, a Laplace operator was introduced to represent the 3D model derived from the statistical shape model. By coordinate transformations in the Laplacian system, novel skeletal features were established and the model was accurately aligned with its 2D image. Finally, 50 femoral models were utilized to verify the effectiveness of this method. The results indicated that the precision of the method was improved by 16.8%-25.9% compared with the traditional statistical shape model reconstruction. Therefore, the method we proposed allows a more accurate 3D bone reconstruction, which facilitates the development of personalized prosthesis design, precise positioning, and quick biomechanical analysis.


Subject(s)
Imaging, Three-Dimensional/methods , Tomography, X-Ray Computed/methods , Femur/surgery , Models, Statistical , Lower Extremity
10.
Beijing Da Xue Xue Bao ; (6): 174-180, 2023.
Article in Chinese | WPRIM | ID: wpr-971292

ABSTRACT

OBJECTIVE@#To explore an efficient and automatic method for determining the anatomical landmarks of three-dimensional(3D) mandibular data, and to preliminarily evaluate the performance of the method.@*METHODS@#The CT data of 40 patients with normal craniofacial morphology were collected (among them, 30 cases were used to establish the 3D mandibular average model, and 10 cases were used as test datasets to validate the performance of this method in determining the mandibular landmarks), and the 3D mandibular data were reconstructed in Mimics software. Among the 40 cases of mandibular data after the 3D reconstruction, 30 cases that were more similar to the mean value of Chinese mandibular features were selected, and the size of the mandibular data of 30 cases was normalized based on the Procrustes analysis algorithm in MATLAB software. Then, in the Geomagic Wrap software, the 3D mandibular average shape model of the above 30 mandibular data was constructed. Through symmetry processing, curvature sampling, index marking and other processing procedures, a 3D mandible structured template with 18 996 semi-landmarks and 19 indexed mandibular anatomical landmarks were constructed. The open source non-rigid registration algorithm program Meshmonk was used to match the 3D mandible template constructed above with the tested patient's 3D mandible data through non-rigid deformation, and 19 anatomical landmark positions of the patient's 3D mandible data were obtained. The accuracy of the research method was evaluated by comparing the distance error of the landmarks manually marked by stomatological experts with the landmarks marked by the method of this research.@*RESULTS@#The method of this study was applied to the data of 10 patients with normal mandibular morphology. The average distance error of 19 landmarks was 1.42 mm, of which the minimum errors were the apex of the coracoid process [right: (1.01±0.44) mm; left: (0.56±0.14) mm] and maximum errors were the anterior edge of the lowest point of anterior ramus [right: (2.52±0.95) mm; left: (2.57±1.10) mm], the average distance error of the midline landmarks was (1.15±0.60) mm, and the average distance error of the bilateral landmarks was (1.51±0.67) mm.@*CONCLUSION@#The automatic determination method of 3D mandibular anatomical landmarks based on 3D mandibular average shape model and non-rigid registration algorithm established in this study can effectively improve the efficiency of automatic labeling of 3D mandibular data features. The automatic determination of anatomical landmarks can basically meet the needs of oral clinical applications, and the labeling effect of deformed mandible data needs to be further tested.


Subject(s)
Humans , Imaging, Three-Dimensional/methods , Mandible/diagnostic imaging , Software , Algorithms , Anatomic Landmarks/anatomy & histology
11.
J. biomed. eng ; Sheng wu yi xue gong cheng xue za zhi;(6): 202-207, 2023.
Article in Chinese | WPRIM | ID: wpr-981530

ABSTRACT

The registration of preoperative magnetic resonance (MR) images and intraoperative ultrasound (US) images is very important in the planning of brain tumor surgery and during surgery. Considering that the two-modality images have different intensity range and resolution, and the US images are degraded by lots of speckle noises, a self-similarity context (SSC) descriptor based on local neighborhood information was adopted to define the similarity measure. The ultrasound images were considered as the reference, the corners were extracted as the key points using three-dimensional differential operators, and the dense displacement sampling discrete optimization algorithm was adopted for registration. The whole registration process was divided into two stages including the affine registration and the elastic registration. In the affine registration stage, the image was decomposed using multi-resolution scheme, and in the elastic registration stage, the displacement vectors of key points were regularized using the minimum convolution and mean field reasoning strategies. The registration experiment was performed on the preoperative MR images and intraoperative US images of 22 patients. The overall error after affine registration was (1.57 ± 0.30) mm, and the average computation time of each pair of images was only 1.36 s; while the overall error after elastic registration was further reduced to (1.40 ± 0.28) mm, and the average registration time was 1.53 s. The experimental results show that the proposed method has prominent registration accuracy and high computational efficiency.


Subject(s)
Humans , Imaging, Three-Dimensional/methods , Magnetic Resonance Imaging/methods , Ultrasonography/methods , Algorithms , Surgery, Computer-Assisted/methods
12.
J. biomed. eng ; Sheng wu yi xue gong cheng xue za zhi;(6): 226-233, 2023.
Article in Chinese | WPRIM | ID: wpr-981533

ABSTRACT

Magnetic resonance (MR) imaging is an important tool for prostate cancer diagnosis, and accurate segmentation of MR prostate regions by computer-aided diagnostic techniques is important for the diagnosis of prostate cancer. In this paper, we propose an improved end-to-end three-dimensional image segmentation network using a deep learning approach to the traditional V-Net network (V-Net) network in order to provide more accurate image segmentation results. Firstly, we fused the soft attention mechanism into the traditional V-Net's jump connection, and combined short jump connection and small convolutional kernel to further improve the network segmentation accuracy. Then the prostate region was segmented using the Prostate MR Image Segmentation 2012 (PROMISE 12) challenge dataset, and the model was evaluated using the dice similarity coefficient (DSC) and Hausdorff distance (HD). The DSC and HD values of the segmented model could reach 0.903 and 3.912 mm, respectively. The experimental results show that the algorithm in this paper can provide more accurate three-dimensional segmentation results, which can accurately and efficiently segment prostate MR images and provide a reliable basis for clinical diagnosis and treatment.


Subject(s)
Male , Humans , Prostate/diagnostic imaging , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Imaging, Three-Dimensional/methods , Prostatic Neoplasms/diagnostic imaging
13.
Article in Chinese | WPRIM | ID: wpr-981630

ABSTRACT

OBJECTIVE@#To investigate the feasibility of MRI three-dimensional (3D) reconstruction model in quantifying glenoid bone defect by comparing with CT 3D reconstruction model measurement.@*METHODS@#Forty patients with shoulder anterior dislocation who met the selection criteria between December 2021 and December 2022 were admitted as study participants. There were 34 males and 6 females with an average age of 24.8 years (range, 19-32 years). The injury caused by sports injury in 29 cases and collision injury in 6 cases, and 5 cases had no obvious inducement. The time from injury to admission ranged from 4 to 72 months (mean, 28.5 months). CT and MRI were performed on the patients' shoulder joints, and a semi-automatic segmentation of the images was done with 3D slicer software to construct a glenoid model. The length of the glenoid bone defect was measured on the models by 2 physicians. The intra-group correlation coefficient ( ICC) was used to evaluate the consistency between the 2 physicians, and Bland-Altman plots were constructed to evaluate the consistency between the 2 methods.@*RESULTS@#The length of the glenoid bone defects measured on MRI 3D reconstruction model was (3.83±1.36) mm/4.00 (0.58, 6.13) mm for physician 1 and (3.91±1.20) mm/3.86 (1.39, 5.96) mm for physician 2. The length of the glenoid bone defects measured on CT 3D reconstruction model was (3.81±1.38) mm/3.80 (0.60, 6.02) mm for physician 1 and (3.99±1.19) mm/4.00 (1.68, 6.38) mm for physician 2. ICC and Bland-Altman plot analysis showed good consistency. The ICC between the 2 physicians based on MRI and CT 3D reconstruction model measurements were 0.73 [95% CI (0.54, 0.85)] and 0.80 [95% CI (0.65, 0.89)], respectively. The 95% CI of the difference between the two measurements of physicians 1 and 2 were (-0.46, 0.49) and (-0.68, 0.53), respectively.@*CONCLUSION@#The measurement of glenoid bone defect based on MRI 3D reconstruction model is consistent with that based on CT 3D reconstruction model. MRI can be used instead of CT to measure glenoid bone defects in clinic, and the soft tissue of shoulder joint can be observed comprehensively while reducing radiation.


Subject(s)
Male , Female , Humans , Young Adult , Adult , Imaging, Three-Dimensional/methods , Tomography, X-Ray Computed/methods , Joint Instability , Shoulder Joint/diagnostic imaging , Shoulder Dislocation , Magnetic Resonance Imaging/methods
14.
Article in English | LILACS, BBO | ID: biblio-1431044

ABSTRACT

Abstract Bitemark analysis is a challenging procedure in the field of criminal case investigation. The unique characteristics of dentition are used to find the best match between the existing patterned injury and the suspected perpetrator in bitemark identification. Bitemark analysis accuracy can be influenced by various factors, including biting pressure, tooth morphology, skin elasticity, dental cast duplication, timing, and image quality. This review article discusses the potential of a smartphone camera as an alternative method for 3D bitemark analysis. Bitemark evidence on human skin and food should be immediately recorded or duplicated to retrieve long-lasting proof, allowing for a sufficient examination period. Various studies utilizing two-dimensional (2D) and three-dimensional (3D) technologies have been developed to obtain an adequate bitemark analysis. 3D imaging technology provides accurate and precise analysis. However, the currently available method using an intraoral scanner (IOS) requires high-cost specialized equipment and a well-trained operator. The numerous advantages of monoscopic photogrammetry may lead to a novel method of 3D bitemark analysis in forensic odontology. Smartphone cameras and monoscopic photogrammetry methodology could lead to a novel method of 3D bitemark analysis with an efficient cost and readily available equipment.


Subject(s)
Bites, Human/diagnostic imaging , Photogrammetry/instrumentation , Smartphone , Forensic Dentistry , Identity Recognition , Forensic Anthropology , Imaging, Three-Dimensional/methods , Odontometry
15.
Rev. Asoc. Odontol. Argent ; 110(2): 1100831, may.-ago. 2022. ilus
Article in Spanish | LILACS | ID: biblio-1418460

ABSTRACT

Objetivo: El odontoma es una lesión hamartomatosa benigna formada por tejido dentario (cemento, esmalte, pul­ pa). Según su grado de diferenciación podrá ser clasificado en sus dos variantes: compuesto y complejo en una relación 2:1. El objetivo de este artículo es presentar un odontoma mixto de gran tamaño de localización mandibular y su resolución quirúrgica. Caso clínico: Se describe el caso de un paciente mascu­ lino de 16 años de edad, portador de ortodoncia, que presenta un odontoma mixto de gran tamaño de localización mandibular y su resolución quirúrgica utilizando planificación 3D y confección de placa de titanio customizada (AU)


Aim: Odontoma is a benign hamartomatous lesion formed by dental tissue (cementum, enamel, pulp). According to its degree of differentiation, it can be classified in its two variants: compound and complex in a 2:1 ratio. The objective of this article is to present a large mixed odontoma of mandi­ bular location and its surgical resolution. Clinical case: A 16-year-old male patient with ortho­ dontics, who presents a large mixed odontoma with mandibu­ lar location and its surgical resolution using 3D planning and customized titanium plate fabrication (AU)


Subject(s)
Humans , Male , Adolescent , Tooth Abnormalities/classification , Odontogenic Tumors/classification , Odontoma/surgery , Mandible/pathology , Patient Care Planning , Argentina , Oral Surgical Procedures, Preprosthetic/methods , Imaging, Three-Dimensional/methods , Dental Service, Hospital , Surgical Fixation Devices , Malocclusion, Angle Class III/therapy
16.
Article in Chinese | WPRIM | ID: wpr-936259

ABSTRACT

Objective: The characteristics of 3D-FLAIR MRI images of the inner ear of patients with vestibular neuritis were preliminarily studied to explore the possible pathogenesis of vestibular neuritis, and the correlation analysis was conducted in combination with vestibular function to provide a basis for accurate diagnosis of vestibular neuritis. Methods: A total of 36 patients with vestibular neuritis (VN) from December 2019 to October 2020 were collected from the Vertigo Department of Shandong Provincial ENT Hospital, Cheeloo College of Medicine, Shandong University. There were 36 cases (18 females, 18 males) with unilateral acute vestibular neuritis, 17 cases of left ear and 19 cases of right ear. According to the results of 3D-FLAIR MRI in the inner ears, the patients were divided into the enhanced group and the non-enhanced group (the health side served as the normal control group). The results of vestibular function examination in the two groups were compared. SPSS19.0 software was used for statistical processing to analyze the relationship between the vestibular function and the characteristics of 3D-FLAIR imaging in the inner ears. Results: Abnormal enhancement of 3D-FLAIR was found in 31 cases (86.1%) of the 36 cases, including 14 cases of both vestibular nerve and vestibular terminal organ enhancement, eight cases of superior vestibular nerve enhancement alone, seven cases of vestibular terminal organ enhancement alone, and two cases of cochlear enhancement alone. Observation of abnormal reinforcement of vestibular nerve showed: twenty-one cases of superior vestibular nerve reinforcement, one case of superior and inferior vestibular nerve reinforcement. No abnormalities were found in 3D-FLAIR of inner ear in 5 cases. According to the analysis of vestibular function results, there were 19 cases (52.8%) with total vestibular involvement, sixteen cases (44.4%) with superior vestibular involvement alone, and one case (2.8%) with inferior vestibular involvement alone. Comparison of vestibular function between the five cases (non-enhancement group) and the 31 cases (enhanced group) in the 3D-FLAIR group of the inner ears showed that the CP values of caloric tests in the enhanced group were higher (60.81±3.49 vs 34.12±7.37), with statistically significant difference (t=-2.898, P<0.01). Conclusion: In patients with vestibular neuritis, 3D-FLAIR MRI scan of the inner ear provides visual imaging evidence for clinical practice, considering that the lesion site of vestibular neuritis is not only in the vestibular nerve, but also in the vestibular end organ. Patients with 3D-FLAIR enhanced in the inner ear may have more significant vestibular function damage.


Subject(s)
Female , Humans , Male , Caloric Tests , Imaging, Three-Dimensional/methods , Magnetic Resonance Imaging/methods , Vestibular Neuronitis/diagnosis , Vestibule, Labyrinth
17.
Chinese Journal of Stomatology ; (12): 358-365, 2022.
Article in Chinese | WPRIM | ID: wpr-935875

ABSTRACT

Objective: To explore the establishment of an efficient and automatic method to determine anatomical landmarks in three-dimensional (3D) facial data, and to evaluate the effectiveness of this method in determining landmarks. Methods: A total of 30 male patients with tooth defect or dentition defect (with good facial symmetry) who visited the Department of Prosthodontics, Peking University School and Hospital of Stomatology from June to August 2021 were selected, and these participants' age was between 18-45 years. 3D facial data of patients was collected and the size normalization and overlap alignment were performed based on the Procrustes analysis algorithm. A 3D face average model was built in Geomagic Studio 2013 software, and a 3D face template was built through parametric processing. MeshLab 2020 software was used to determine the serial number information of 32 facial anatomical landmarks (10 midline landmarks and 22 bilateral landmarks). Five male patients with no mandibular deviation and 5 with mild mandibular deviation were selected from the Department of Orthodontics or Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology from June to August 2021. 3D facial data of patients was collected as test data. Based on the 3D face template and the serial number information of the facial anatomical landmarks, the coordinates of 32 facial anatomical landmarks on the test data were automatically determined with the help of the MeshMonk non-rigid registration algorithm program, as the data for the template method to determine the landmarks. The positions of 32 facial anatomical landmarks on the test data were manually determined by the same attending physician, and the coordinates of the landmarks were recorded as the data for determining landmarks by the expert method. Calculated the distance value of the coordinates of facial anatomical landmarks between the template method and the expert method, as the landmark localization error, and evaluated the effect of the template method in determining the landmarks. Results: For 5 patients with no mandibular deviation, the landmark localization error of all facial anatomical landmarks by template method was (1.65±1.19) mm, the landmark localization error of the midline facial anatomical landmarks was (1.19±0.45) mm, the landmark localization error of bilateral facial anatomical landmarks was (1.85±1.33) mm. For 5 patients with mild mandibular deviation, the landmark localization error of all facial anatomical landmarks by template method was (2.55±2.22) mm, the landmark localization error of the midline facial anatomical landmarks was (1.85±1.13) mm, the landmark localization error of bilateral facial anatomical landmarks was (2.87±2.45) mm. Conclusions: The automatic determination method of facial anatomical landmarks proposed in this study has certain feasibility, and the determination effect of midline facial anatomical landmarks is better than that of bilateral facial anatomical landmarks. The effect of determining facial anatomical landmarks in patients without mandibular deviation is better than that in patients with mild mandibular deviation.


Subject(s)
Adolescent , Adult , Female , Humans , Male , Middle Aged , Young Adult , Algorithms , Anatomic Landmarks , Cephalometry/methods , Face/anatomy & histology , Imaging, Three-Dimensional/methods , Malocclusion , Orthodontics , Software
18.
Neuroscience Bulletin ; (6): 303-317, 2022.
Article in English | WPRIM | ID: wpr-929085

ABSTRACT

Understanding the connection between brain and behavior in animals requires precise monitoring of their behaviors in three-dimensional (3-D) space. However, there is no available three-dimensional behavior capture system that focuses on rodents. Here, we present MouseVenue3D, an automated and low-cost system for the efficient capture of 3-D skeleton trajectories in markerless rodents. We improved the most time-consuming step in 3-D behavior capturing by developing an automatic calibration module. Then, we validated this process in behavior recognition tasks, and showed that 3-D behavioral data achieved higher accuracy than 2-D data. Subsequently, MouseVenue3D was combined with fast high-resolution miniature two-photon microscopy for synchronous neural recording and behavioral tracking in the freely-moving mouse. Finally, we successfully decoded spontaneous neuronal activity from the 3-D behavior of mice. Our findings reveal that subtle, spontaneous behavior modules are strongly correlated with spontaneous neuronal activity patterns.


Subject(s)
Animals , Mice , Behavior, Animal , Brain/diagnostic imaging , Imaging, Three-Dimensional/methods , Neuroimaging , Rodentia
19.
J. biomed. eng ; Sheng wu yi xue gong cheng xue za zhi;(6): 1218-1232, 2022.
Article in Chinese | WPRIM | ID: wpr-970661

ABSTRACT

In recent years, the task of object detection and segmentation in medical image is the research hotspot and difficulty in the field of image processing. Instance segmentation provides instance-level labels for different objects belonging to the same class, so it is widely used in the field of medical image processing. In this paper, medical image instance segmentation was summarized from the following aspects: First, the basic principle of instance segmentation was described, the instance segmentation models were classified into three categories, the development context of the instance segmentation algorithm was displayed in two-dimensional space, and six classic model diagrams of instance segmentation were given. Second, from the perspective of the three models of two-stage instance segmentation, single-stage instance segmentation and three-dimensional (3D) instance segmentation, we summarized the ideas of the three types of models, discussed the advantages and disadvantages, and sorted out the latest developments. Third, the application status of instance segmentation in six medical images such as colon tissue image, cervical image, bone imaging image, pathological section image of gastric cancer, computed tomography (CT) image of lung nodule and X-ray image of breast was summarized. Fourth, the main challenges in the field of medical image instance segmentation were discussed and the future development direction was prospected. In this paper, the principle, models and characteristics of instance segmentation are systematically summarized, as well as the application of instance segmentation in the field of medical image processing, which is of positive guiding significance to the study of instance segmentation.


Subject(s)
Imaging, Three-Dimensional/methods , Image Processing, Computer-Assisted , Tomography, X-Ray Computed/methods , Algorithms
20.
Int. j. morphol ; 40(5): 1344-1348, 2022. ilus
Article in English | LILACS | ID: biblio-1405281

ABSTRACT

SUMMARY: Intracranial artery stenosis (ICAS) was one of the main causes of ischemic stroke onset and recurrence. About 30 % of strokes were caused by intracranial artery stenosis. Intracranial artery stenosis had a high incidence in China and faced a high risk of recurrence for a long time. It affected patient safety and quality of life seriously. At the same time, it caused a heavy financial burden for the patient´s family. Therefore, early detection and accuracy of intracranial artery stenosis evaluation were extremely important. High-resolution magnetic resonance imaging (HR-MRI) had been widely used in clinical examinations, making up for the shortcomings of traditional vascular imaging methods that could only show the degree of luminal stenosis, making it possible to perform lumens, tube wall and plaque features of atherosclerotic intracranial arteries at the same time. There were still some controversies about the credibility of this technique in assessing the intracranial artery lumen stenosis. This article reviewed the application efficacy of HR-MRI technology in evaluating the degree of intracranial atherosclerotic stenosis.


RESUMEN: La estenosis de arterias intracraneales (ICAS) es una de las principales causas del ictus isquémico, como así también de su recurrencia. Alrededor del 30 % de los ataques cerebrovasculares son causados por estenosis de la arteria intracraneal. La estenosis de arterias intracraneales tiene una alta incidencia en China y enfrenta un alto riesgo de recurrencia, afectando gravemente la seguridad y la calidad de vida de los pacientes. Al mismo tiempo, supone una importante carga financiera para la familia de los pacientes. Por lo tanto, la detección temprana y la precisión de la evaluación de la estenosis de arterias intracraneales es extremadamente importante. La resonancia magnética de alta resolución (HR-MRI, por sus siglas en inglés) es utilizada ampliamente en los exámenes clínicos, compensando las deficiencias de los métodos tradicionales de imágenes vasculares que solo pueden mostrar el grado de estenosis luminal, haciendo posible el estudio de las características del lumen, pared vascular y la placa ateroesclerótica, de las arterias intracraneales afectadas, al mismo tiempo. Aún existen algunas controversias sobre la credibilidad de esta técnica en la evaluación de la estenosis del lumen de arterias intracraneales. En este artículo se revisó la eficacia de la aplicación de la tecnología HR-MRI para evaluar el grado de estenosis aterosclerótica intracraneal.


Subject(s)
Humans , Magnetic Resonance Imaging/methods , Intracranial Arteriosclerosis/diagnostic imaging , Imaging, Three-Dimensional/methods , Constriction, Pathologic/diagnostic imaging , Stroke/prevention & control
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