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1.
Angle Orthod ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39223719

RESUMEN

OBJECTIVE: In this retrospective case-control study, we aimed to evaluate the nasopharyngeal airway volume of children with Down syndrome (DS) and compare the results with those of control participants well matched for sex and age. MATERIALS AND METHODS: Fifteen children with DS (mean age = 9.43 ± 0.38 years; 8 boys, 7 girls) and 15 control participants (mean age = 9.51 ± 0.40 years; 8 boys, 7 girls) were enrolled. The nasopharyngeal airway volume and the cross-sectional morphology were measured with cone-beam computed tomography taken for orthodontic treatment. All measurements were assessed by analysis of covariance (ANCOVA) using Bonferroni post hoc pairwise comparison tests. Covariates were body height and body weight, and the ANB angle and the mandibular plane angle. Significance was set at P < .0019. RESULTS: Nasal airway, superior airway, and total airway volumes of DS participants were significantly smaller than those of the control participants in ANCOVA results adjusted for ANB angle and mandibular plane angle (P = .000). In ANCOVA results adjusted for body height and body weight, no statistically significant differences in the volume measurements were found. CONCLUSION: The results indicate that the nasopharyngeal airway volume differs between children with and without DS and that the airway volume tends to be smaller in DS children than in children without DS.

2.
Sensors (Basel) ; 24(16)2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39205140

RESUMEN

Accurate and precise rigid registration between head-neck computed tomography (CT) and cone-beam computed tomography (CBCT) images is crucial for correcting setup errors in image-guided radiotherapy (IGRT) for head and neck tumors. However, conventional registration methods that treat the head and neck as a single entity may not achieve the necessary accuracy for the head region, which is particularly sensitive to radiation in radiotherapy. We propose ACSwinNet, a deep learning-based method for head-neck CT-CBCT rigid registration, which aims to enhance the registration precision in the head region. Our approach integrates an anatomical constraint encoder with anatomical segmentations of tissues and organs to enhance the accuracy of rigid registration in the head region. We also employ a Swin Transformer-based network for registration in cases with large initial misalignment and a perceptual similarity metric network to address intensity discrepancies and artifacts between the CT and CBCT images. We validate the proposed method using a head-neck CT-CBCT dataset acquired from clinical patients. Compared with the conventional rigid method, our method exhibits lower target registration error (TRE) for landmarks in the head region (reduced from 2.14 ± 0.45 mm to 1.82 ± 0.39 mm), higher dice similarity coefficient (DSC) (increased from 0.743 ± 0.051 to 0.755 ± 0.053), and higher structural similarity index (increased from 0.854 ± 0.044 to 0.870 ± 0.043). Our proposed method effectively addresses the challenge of low registration accuracy in the head region, which has been a limitation of conventional methods. This demonstrates significant potential in improving the accuracy of IGRT for head and neck tumors.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Aprendizaje Profundo , Neoplasias de Cabeza y Cuello , Radioterapia Guiada por Imagen , Humanos , Radioterapia Guiada por Imagen/métodos , Tomografía Computarizada de Haz Cónico/métodos , Neoplasias de Cabeza y Cuello/radioterapia , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Algoritmos , Cabeza/diagnóstico por imagen , Cuello/diagnóstico por imagen
3.
Phys Med ; 125: 104502, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39216313

RESUMEN

PURPOSE: This study aims to evaluate the positioning correction extracted from Intra-fraction Cone Beam (IF-CBCT) images obtained during Stereotactic Body Radiotherapy (SBRT) treatments, and to assess whether its magnitude justifies its acquisition. In addition, the results obtained in lung, liver, and pancreas SBRTs with two deep inspiration breath-hold systems (DIBH), and for prostate with/without ultrasound (US) monitoring were compared. METHODS: 1449 treatments, performed with two linear accelerators (LINACs) were retrospectively analyzed. DIBH were performed either with a spirometry-based device or a surface-guidance system and one LINAC was equipped with US monitoring system for prostate. Significance tests were used to account for differences between units. RESULTS: Group systematic error (M) was approximately -0.7 mm for DIBH treatments in superior-inferior (SI) direction with no difference (p > 0.7) between LINACs. Moreover, there was a SI difference of 0.5 mm for prostate treatments (p = 0.008), in favor of the US monitored one. In anterior-posterior (AP) direction, only liver treatments exhibited differences between LINACs, with the spirometer-based system being 0.8 mm inferior (p = 0.003). M<0.4 mm in left-right (LR) direction was found for all locations and LINACs. The spirometer-based system resulted in lower standard deviation of systematic and random errors in most components and locations, with a greater effect observed in liver SBRTs. CONCLUSIONS: The corrections made with IF-CBCT during SBRT treatments were not negligible. Both DIBH systems were effective in managing respiratory movements. However, the spirometry-based system was slightly more accurate. In addition, US monitoring of the prostate appeared to be useful in reducing target shift.

4.
BMC Oral Health ; 24(1): 953, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39152371

RESUMEN

BACKGROUND: To evaluate the accuracy of the electronic apex locators (EALs), and Cone-Beam Computed Tomography (CBCT) scanning, both in working length (WL) determination and in the detection of root canal perforations in retreatment cases. METHODS: Sixty human mandibular premolars were selected. After crown removal partially and canal access, root canals were instrumented and irrigated. The obturation process utilized gutta-percha and sealer with warm vertical compaction. Two groups were distinguished: one without perforation (Group 1) and the other with an apical third perforation (Group 2). Retreatment included filling removal, apical preparation, and irrigation. Actual working lengths (AWL) were determined using a stereomicroscope. CBCT images were used to measure CBCT working length (CWL), with adjustments for optimal views. Propex II and Dentaport ZX were used to measure electronic working length (EWL). Differences between EWL and AWL, as well as CWL, were analyzed to gauge accuracy. Data underwent Two-way ANOVA analysis. Measurements within ± 0.5 and ± 1 mm tolerance ranges were deemed successful for each device, followed by applying the Pearson Chi-square test. RESULTS: The study reveals no significant inter-group variations in device performance (p > .05). Dentaport ZX missed detecting perforation in two Group 2 (apical perforation) cases. For ± 1 mm tolerance, Propex II displayed the highest success in Group 2 (apical perforation). CONCLUSION: This study demonstrates the comparable performance of Propex II, Dentaport ZX, and CBCT in endodontic retreatment, providing insights into diagnostic reliability.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Cavidad Pulpar , Odontometría , Retratamiento , Preparación del Conducto Radicular , Ápice del Diente , Humanos , Cavidad Pulpar/diagnóstico por imagen , Cavidad Pulpar/anatomía & histología , Ápice del Diente/diagnóstico por imagen , Ápice del Diente/anatomía & histología , Preparación del Conducto Radicular/instrumentación , Odontometría/instrumentación , Odontometría/métodos , Diente Premolar/diagnóstico por imagen , Diente Premolar/lesiones , Tratamiento del Conducto Radicular/instrumentación , Obturación del Conducto Radicular
5.
Clin Oral Investig ; 28(9): 484, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39138740

RESUMEN

OBJECTIVES: To assess and compare the clinical, radiological, and histological outcomes of socket seal surgery between two protocols: deproteinized demineralized tooth matrix (dpDTM) and freeze-dried bone allograft (FDBA) each covered with a free gingival graft. MATERIALS AND METHODS: Twenty extraction sockets in the anterior or premolar region were randomly allocated to either the dpDTM or FDBA protocol (n = 10 per group). Measurements of the alveolar ridge changes were obtained using an intraoral scanner and cone-beam computed tomography at 3 months post-operation. Three-month post surgery, the dental implant was installed (n = 5 per group), bone biopsies were obtained for histomorphometrical and micro-computed tomography analyses. Implant stability quotients (ISQs) were determined and compared at 3 months post-implant. RESULTS: Lower significant reductions in buccal alveolar ridge height and hard tissue volume were observed in dpDTM group compared to FDBA group at 3 months (0.25 ± 0.35 mm vs. 1.60 ± 0.66 mm [p = .000] and 9.64 ± 15.39% mm3 vs. 31.45 ± 18.11% mm3 [p = .010], respectively). At the same time, lower soft tissue volume reduction was detected in the dpDTM group compared to FDBA group (4.21 ± 5.25% mm3 vs. 5.25 ± 5.79% mm3). No statistically significant difference in the percentage of mineralized tissue formation was found between dpDTM group (53.39 ± 11.16%) and FDBA group (49.90 ± 3.27%). Even though the ISQ in the dpDTM group showed a higher value than the FDBA group at 3 months post-implant, the results were without statistical significance. CONCLUSIONS: Alveolar ridge preservation using dpDTM is an efficacious procedure for providing the conditions for the development of functional and esthetic implants.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Alveolo Dental , Humanos , Alveolo Dental/cirugía , Masculino , Femenino , Persona de Mediana Edad , Adulto , Resultado del Tratamiento , Trasplante Óseo/métodos , Microtomografía por Rayos X , Implantación Dental Endoósea/métodos , Aumento de la Cresta Alveolar/métodos , Extracción Dental , Biopsia , Encía , Pérdida de Hueso Alveolar/prevención & control , Pérdida de Hueso Alveolar/diagnóstico por imagen , Proceso Alveolar/diagnóstico por imagen , Proceso Alveolar/patología , Proceso Alveolar/cirugía , Dentina
6.
Cureus ; 16(7): e64456, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39139310

RESUMEN

Cleidocranial dysplasia (CCD) is a rare, congenital disorder characterized by a unique constellation of skeletal and dental abnormalities. The imaging findings, combined with clinical examination, help establish a definitive diagnosis. Understanding the broad spectrum of manifestations in CCD is essential for effective management and treatment. This case report aims to provide a comprehensive overview of a 25-year-old male patient with CCD, highlighting the genetic etiologies, clinical presentation, radiological findings, and a review of current literature to enhance understanding and awareness of this rare condition.

7.
Radiat Oncol ; 19(1): 109, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39143640

RESUMEN

BACKGROUND AND PURPOSE: Cone beam computed tomography (CBCT) is routinely used in radiotherapy to localize target volume. The aim of our study was to determine the biological effects of CBCT dose compared to subsequent therapeutic dose by using in vitro chromosome dosimetry. MATERIALS AND METHODS: Peripheral blood samples from five healthy volunteers were irradiated in two phantoms (water filled in-house made cylindrical, and Pure Image CTDI phantoms) with 6 MV FFF X-ray photons, the dose rate was 800 MU/min and the absorbed doses ranged from 0.5 to 8 Gy. Irradiation was performed with a 6 MV linear accelerator (LINAC) to generate a dose-response calibration curve. In the first part of the investigation, 1-5 CBCT imaging was used, in the second, only 2 Gy doses were delivered with a LINAC, and then, in the third part, a combination of CBCT and 2 Gy irradiation was performed mimicking online adapted radiotherapy treatment. Metaphases were prepared from lymphocyte cultures, using standard cytogenetic techniques, and chromosomal aberrations were evaluated. Estimate doses were calculated from chromosome aberrations using dose-response curves. RESULTS: Samples exposed to X-ray from CBCT imaging prior to treatment exhibited higher chromosomal aberrations and Estimate dose than the 2 Gy therapeutic (real) dose, and the magnitude of the increase depended on the number of CBCTs: 1-5 CBCT corresponded to 0.04-0.92 Gy, 1 CBCT + 2 Gy to 2.32 Gy, and 5 CBCTs + 2 Gy to 3.5 Gy. CONCLUSION: The estimated dose based on chromosomal aberrations is 24.8% higher than the physical dose, for the combination of 3 CBCTs and the therapeutic 2 Gy dose, which should be taken into account when calculating the total therapeutic dose that could increase the risk of a second cancer. The clinical implications of the combined radiation effect may require further investigation.


Asunto(s)
Aberraciones Cromosómicas , Tomografía Computarizada de Haz Cónico , Linfocitos , Fantasmas de Imagen , Dosificación Radioterapéutica , Humanos , Tomografía Computarizada de Haz Cónico/métodos , Aberraciones Cromosómicas/efectos de la radiación , Linfocitos/efectos de la radiación , Rayos X , Relación Dosis-Respuesta en la Radiación , Radiometría/métodos
8.
Front Oncol ; 14: 1390398, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39161388

RESUMEN

Purpose: To enhance the accuracy of real-time four-dimensional cone beam CT (4D-CBCT) imaging by incorporating spatiotemporal correlation from the sequential projection image into the single projection-based 4D-CBCT estimation process. Methods: We first derived 4D deformation vector fields (DVFs) from patient 4D-CT. Principal component analysis (PCA) was then employed to extract distinctive feature labels for each DVF, focusing on the first three PCA coefficients. To simulate a wide range of respiratory motion, we expanded the motion amplitude and used random sampling to generate approximately 900 sets of PCA labels. These labels were used to produce 900 simulated 4D-DVFs, which in turn deformed the 0% phase 4D-CT to obtain 900 CBCT volumes with continuous motion amplitudes. Following this, the forward projection was performed at one angle to get all of the digital reconstructed radiographs (DRRs). These DRRs and the PCA labels were used as the training data set. To capture the spatiotemporal correlation in the projections, we propose to use the convolutional LSTM (ConvLSTM) network for PCA coefficient estimation. For network testing, when several online CBCT projections (with different motion amplitudes that cover the full respiration range) are acquired and sent into the network, the corresponding 4D-PCA coefficients will be obtained and finally lead to a full online 4D-CBCT prediction. A phantom experiment is first performed with the XCAT phantom; then, a pilot clinical evaluation is further conducted. Results: Results on the XCAT phantom and the patient data show that the proposed approach outperformed other networks in terms of visual inspection and quantitative metrics. For the XCAT phantom experiment, ConvLSTM achieves the highest quantification accuracy with MAPE(Mean Absolute Percentage Error), PSNR (Peak Signal-to-Noise Ratio), and RMSE(Root Mean Squared Error) of 0.0459, 64.6742, and 0.0011, respectively. For the patient pilot clinical experiment, ConvLSTM also achieves the best quantification accuracy with that of 0.0934, 63.7294, and 0.0019, respectively. The quantification evaluation labels that we used are 1) the Mean Absolute Error (MAE), 2) the Normalized Cross Correlation (NCC), 3)the Structural Similarity Index Measurement(SSIM), 4)the Peak Signal-to-Noise Ratio (PSNR), 5)the Root Mean Squared Error(RMSE), and 6) the Absolute Percentage Error (MAPE). Conclusion: The spatiotemporal correlation-based respiration motion modeling supplied a potential solution for accurate real-time 4D-CBCT reconstruction.

9.
Front Oncol ; 14: 1440944, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39175474

RESUMEN

Background: Cone-beam computed tomography (CBCT) is a convenient method for adaptive radiation therapy (ART), but its application is often hindered by its image quality. We aim to develop a unified deep learning model that can consistently enhance the quality of CBCT images across various anatomical sites by generating synthetic CT (sCT) images. Methods: A dataset of paired CBCT and planning CT images from 135 cancer patients, including head and neck, chest and abdominal tumors, was collected. This dataset, with its rich anatomical diversity and scanning parameters, was carefully selected to ensure comprehensive model training. Due to the imperfect registration, the inherent challenge of local structural misalignment of paired dataset may lead to suboptimal model performance. To address this limitation, we propose SynREG, a supervised learning framework. SynREG integrates a hybrid CNN-transformer architecture designed for generating high-fidelity sCT images and a registration network designed to correct local structural misalignment dynamically during training. An independent test set of 23 additional patients was used to evaluate the image quality, and the results were compared with those of several benchmark models (pix2pix, cycleGAN and SwinIR). Furthermore, the performance of an autosegmentation application was also assessed. Results: The proposed model disentangled sCT generation from anatomical correction, leading to a more rational optimization process. As a result, the model effectively suppressed noise and artifacts in multisite applications, significantly enhancing CBCT image quality. Specifically, the mean absolute error (MAE) of SynREG was reduced to 16.81 ± 8.42 HU, whereas the structural similarity index (SSIM) increased to 94.34 ± 2.85%, representing improvements over the raw CBCT data, which had the MAE of 26.74 ± 10.11 HU and the SSIM of 89.73 ± 3.46%. The enhanced image quality was particularly beneficial for organs with low contrast resolution, significantly increasing the accuracy of automatic segmentation in these regions. Notably, for the brainstem, the mean Dice similarity coefficient (DSC) increased from 0.61 to 0.89, and the MDA decreased from 3.72 mm to 0.98 mm, indicating a substantial improvement in segmentation accuracy and precision. Conclusions: SynREG can effectively alleviate the differences in residual anatomy between paired datasets and enhance the quality of CBCT images.

10.
Surg Radiol Anat ; 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39150555

RESUMEN

PURPOSE: Various anatomical variations of the inferior alveolar canal increase the incidence of surgical complications; Therefore, this study aimed to evaluate the frequency and configuration of bifid and trifid mandibular canals using cone beam computed tomography (CBCT) in the Turkish subpopulation. METHODS: The inferior alveolar canal was evaluated on 1014 hemi-mandibles in the CBCT (I-CAT 3D Imaging System) images of 513 patients. The frequency and configuration of the bifid and trifid mandibular canal (MC) were examined. The relationship between bifid MC configuration and dental status and age groups was analyzed. The distance of the accessory canal to the buccal and lingual walls and the alveolar crest was measured. The diameter of the main canal and accessory canal was measured and its relationship with dental status and age groups was evaluated. RESULTS: Bifid MC was found in 266 hemi-mandibles (24.7%) and 212 (41.3%) of 513 patients. The most common type of bifid MC was the retromolar canal (87 sides), followed by the forward canal without confluence (41; 4%) and the dental canal (34; 3.4%). 10 of the dental canals were opening to the 1st molar, 14 of the 2nd molars, and 10 of the 3rd molars. The number of retromolar foramina was 1 on 56 sides, 2 on 15 sides, and 3 on 4 sides. Forward canal without confluence was more common in edentulous patients than in dentulous patients, while the dental canal was more common in dentulous patients. The main canal diameter was 3.53 ± 0.97 mm and the bifid MC diameter was 1.82 ± 0.70 mm. Distance of the bifid MC to the lingual wall was higher in the > 64 years group than in the 18-39 years group (p = 0.022). Distance of the bifid MC to the alveolar crest was lower in the > 64 years group compared to the 18-39 years group and 40-64 years group (p = 0.015). The main canal diameter was higher in the 40-64 years group than in the 18-39 years group (p = 0.012). CONCLUSION: Bifid MC has a high prevalence, occurring in almost one in two patients. Dental and retromolar types, which are close to the teeth, are more common, and this increases the possibility of complications. CBCT is the most accurate imaging technique used to detect and define these variations.

11.
Cureus ; 16(7): e65287, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39184735

RESUMEN

BACKGROUND: Age estimation, whether for living or deceased individuals, is crucial in forensic sciences. Traditionally, the pulp-to-tooth area ratio determined from periapical radiographs has been employed as a non-invasive method for estimating age. Cone-beam computed tomography (CBCT) represents a newer technique, providing three-dimensional images of teeth in living individuals. AIM: This study aims to estimate age using the pulp-to-tooth area ratio of four teeth (the permanent maxillary central incisor, lateral incisor, canine, and first premolar. STUDY DESIGN: The study included ninety subjects ranging in age from 18 to 70 years. CONCLUSION: This study concluded that the correlation between actual age and estimated age varied across different tooth types. There was a strong positive correlation between the maxillary right central incisor and maxillary right canine tooth, while the maxillary left canine tooth exhibited a slightly weaker but still positive correlation. This indicates that the maxillary right central incisor and maxillary right canine tooth are the most reliable for estimating age. Additionally, the study found that the linear regression results for estimating age based on the pulp-to-tooth area ratio, categorised by sex and each type of tooth, showed strong associations between age and the ratio for the maxillary left central incisor and maxillary left canine teeth in males, and for the maxillary left central incisor in females.

12.
Ann Anat ; : 152325, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39197665

RESUMEN

BACKGROUND: The aim of this study was to determine the effect of root canal filling using different obturation materials combined with apicoectomy in upper central incisors under loading with 1N and 100N. The effect of incomplete root formation was also investigated. METHODS: Based on a CBCT-scan, a model of an upper central incisor was created. The model was altered to simulate different clinical situations: root canal treatment, apicoectomy at two different lengths and with different obturation protocols, and immature root formation after trauma. In each model the tooth was loaded with 1 and 100N, and peak Von Mises stress of bone and tooth, elastic strain of the periodontal ligament, as well as rotation and displacement of the tooth were measured. RESULTS: Periapical surgery increases stress in dentin and the surrounding bone. Different obturation materials only produce minor differences in a coronally intact tooth. CONCLUSIONS: Interincisal angle or loading direction strongly affects all measured values and needs to be considered when planning periapical surgery or comparing finite element analysis. Immature roots show the highest stress values in this study, reaching half the yield strength of dentine.

13.
Spine J ; 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39154945

RESUMEN

BACKGROUND: Intraoperative 3D imaging with cone-beam CT (CBCT) improves assessment of implant position and reduces complications in spine surgery. It is also used for image-guided surgical techniques, resulting in improved quality of care. However, in some cases, metal artifacts can reduce image quality and make it difficult to assess pedicle screw position and reduction. PURPOSE: The objective of this study was to investigate whether a change in CBCT acquisition trajectory in relation to pedicle screw position during dorsal instrumentation can reduce metal artifacts and consequently improve image quality and clinical assessability. STUDY DESIGN: Experimental cadaver study. METHODS: A human cadaver was instrumented with pedicle screws in the thoracic and lumbar spine region (Th11 to L5). Then, the acquisition trajectory of the CBCT (Cios Spin, Siemens, Germany) to the pedicle screws was systematically changed in 5° steps in angulation (-30° to +30°) and swivel (-25° to +25°). Subsequently, radiological evaluation was performed by 3 blinded, qualified raters on image quality using 9 questions (including anatomical structures, implant position, appearance of artifacts) with a score (1-5 points). For statistical evaluation, the image quality of the different acquisition trajectories was compared to the standard acquisition trajectory and checked for significant differences. RESULTS: The angulated acquisition trajectory significantly increased the score for subjective image quality (p<.001) as well as the clinical assessability of pedicle screw position (p<.001) with particularly strong effects on subjective image quality in the vertebral pedicle region (d=1.61). Swivel of the acquisition trajectory significantly improved all queried domains of subjective image quality (p<.001) as well as clinical assessability of pedicle screw position (p<.001). CONCLUSIONS: In this cadaver study, the angulation as well as the swivel of the acquisition trajectory led to a significantly improved image quality in intraoperative 3D imaging (CBCT) with a constant isocenter. The data show that maximizing the angulation/swivel angle towards 30°/25° provides the best tested subjective image quality and enhances clinical assessability. Therefore, a correct adjustment of the acquisition trajectory can help to make intraoperative revision decisions more reliably. CLINICAL SIGNIFICANCE: The knowledge of enhanced image quality by changing the acquisition trajectory in intraoperative 3D imaging can be used for the assessment of critical screw positions in spine surgery. The implementation of this knowledge requires only a minor change of the current intraoperative imaging workflow without additional technical equipment and could further reduce the need for revision surgery.

14.
Bioengineering (Basel) ; 11(8)2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39199713

RESUMEN

The Eustachian tube (ET) is a bottleneck when it comes to middle ear (ME) health. If its function is impaired, this can lead to serious consequences for the patient, such as hearing problems or deafness. Therefore, this study investigated a tapered nitinol stent (3-5 mm × 14 mm) for the human ET as a potential new permanent treatment for chronic Eustachian tube dysfunction (ETD) and thus ME ventilation disorders. The self-expanding stent was inserted unilaterally into the ET of 24 sheep with observation periods of 3, 6, and 12 months. Local tissue effects and the safety of the stent insertion were analyzed based on regular endoscopic checks, weekly tympanometry measurements, final imaging, and histological examinations. The animals showed no stent-related health restrictions. However, the individual anatomy and stenting procedure had an influence on the results. The tissue reaction in the endoscopic examinations was mild even though no concomitant antibiotics were administered. After all three monitoring periods, stented ETs had a significantly larger ET lumen than the non-stented contralateral ETs. However, tissue growth was detected in the stent. Overall, the first long-term study on an ET stent showed that the tapered ET stent could be a promising treatment option for ETD.

15.
J Forensic Leg Med ; 107: 102742, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39213905

RESUMEN

OBJECTIVE: The aim of this study was to estimate the chronological age (CA) of a growing individual using a new machine learning approach on Cone Beam Computed Tomography (CBCT). MATERIALS AND METHODS: The dataset included 48 CBCT and hand-wrist radiographs of growing individuals. 12 landmarks related to trigeminal trajectories were plotted on each CBCT and principal component analysis was applied for dimensionality reduction. The estimated CA was obtained using a decision tree. Finally, a genetic algorithm was implemented to select the best set of landmarks that would optimize the estimation. The age was also assessed following Greulich and Pyle's (GP) method on hand-wrist radiographs. The results (GP and Machine Learning) were then compared to the true CA. RESULTS: Among the 12 landmarks, the genetic algorithm selected 7 optimal features, and 12 principal components out of 36. The best results for age prediction were obtained by a combination of genetic algorithm, principal component analysis, and regression tree where the Mean Squared Error (MSE) and Mean Absolute Error (MAE) were respectively 1.29 and 0.92. These outcomes showed improved accuracy compared to those of the hand-wrist method (MSE = 2.038 and MAE = 1.775). CONCLUSIONS: A numerical application on a dataset of CBCT showed that the proposed machine learning method achieved an improved accuracy compared to conventional methods and had satisfying performance in assessing age for forensic purposes. Validation of the presented method on a larger and more diverse sample would pave the way for future applications in forensic science as a tool for age prediction.

16.
Children (Basel) ; 11(8)2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39201947

RESUMEN

BACKGROUND: The evaluation of midpalatal suture maturation is essential to undertake the most predictable maxillary expansion approach. Several factors, such as age, gender, and facial growth patterns, seem to be involved in midpalatal suture staging and, consequently, in its opening; however, the link between these variables and the stages of midpalatal suture development remains poorly understood. Our study aimed to analyse the midpalatal suture maturation in relation to age, sex, and skeletal growth patterns by CBCT. METHODS: We enrolled 263 patients (119 males and 144 females) aged from 8 to 20 years. The midpalatal suture maturation was defined according to Angelieri et al.'s classification using a low-dose CBCT. The chi-square test and linear regression were applied to investigate the suture stages by age, sex, and vertical and sagittal growth patterns. RESULTS: Stage A was present in 8- and 9-year-olds with a larger prevalence in boys, while the prevalence of stage E increased progressively with age. Stage D was the most prevalent in our sample. The statistical analysis described that stage A was more likely in the youngest subjects, and stage E in the oldest participants. The males tended to have lower maturation stages. Moreover, the hypodivergent and normodivergent subjects tended to have higher maturation stages, while Class III was more likely in subjects in stages D or E. CONCLUSIONS: A total of 127 patients were in stages A, B, and C, showing an unfused suture. In young individuals, the opening of the midpalatal suture leads to a proper facial growth development by correcting the transverse superior hypoplasia. The midpalatal sutural maturation classification was related to age, sex, and divergence.

17.
Diagnostics (Basel) ; 14(16)2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39202187

RESUMEN

Medication-related osteonecrosis of the jaw (MRONJ) is a debilitating condition associated with antiresorptive and antiangiogenic medications that are frequently used in treating osteoporosis and cancers. With the ability to produce high-resolution images with a lower radiation dose, cone beam computed tomography (CBCT) is an emerging technology in maxillofacial imaging that offers several advantages in evaluating MRONJ. This review aims to summarise the radiological features of MRONJ as observed via CBCT and highlight its advantages over two-dimensional plain films in assessing MRONJ. CBCT has the capability to detect early MRONJ lesions, characterise the extent and nature of lesions, distinguish MRONJ from other osseous pathologies, and assist in treatment planning. By leveraging the advantages of CBCT, clinicians can enhance their understanding of MRONJ, improve decision making, and ultimately optimize patient care.

18.
Diagnostics (Basel) ; 14(16)2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39202245

RESUMEN

BACKGROUND: For years, there has been a long debate about the impact of orthodontic treatment on the periodontium of patients. Therefore, it is important to understand the effects of orthodontic forces on the periodontium. The objective of this study was to evaluate the height of the alveolar bone at the four surfaces of specific teeth and the root length of the central incisors before and after orthodontic treatment. MATERIALS AND METHODS: CBCTs from a group of fifty patients were evaluated before (T0) and after orthodontic treatment (T1). Evaluations of the alveolar bone were performed by measuring the distance from the most apical point of the marginal portion to the CEJ at the buccal (B-ABL), lingual (L-ABL), mesial (M-ABL), and distal (D-ABL) surfaces of the central incisor (CI), first premolar (1st PM), and first molar (1st M). Meanwhile, root resorptions were evaluated by measuring the distance from the center of the tooth at the CEJ to the most apical point of the central incisor. RESULTS: The reduction in the alveolar bone level was highest at the buccal segment (75%) and lowest at the distal (42%) segment, although the decrease was not statistically significant. Root resorption, in terms of reduction in the total length, was detected in the upper central incisor. CONCLUSIONS: Fixed orthodontic treatment can produce a significant reduction in root length, but not at the level of the alveolar bone.

19.
Radiother Oncol ; 199: 110471, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39127406

RESUMEN

BACKGROUND AND PURPOSE: The quality of the Cone Beam Computed Tomography (CBCT) images used for patient set-up is essential to avoid geographical miss when narrower margins or shorter fractionation are used for example in Accelerated Partial Breast Irradiation (APBI). This study evaluates deep inspiration breath hold (DIBH) with skin guided radiotherapy as a tool for image improvement reducing motion artifacts. MATERIALS AND METHODS: Daily CBCT images of left and right breast cancer patients with well-defined surgical cavity on CT simulation were used for this study. Only left sided CBCT were acquired with DIBH. Trained and experienced radiation therapists were asked to evaluate the image quality using a cavity visualization score (CVS), an image quality Likert score, and to perform registration shifts. Images were anonymized and therapists were blinded to the use of DIBH. RESULTS: Images from 21 patients, with 15 CBCT each, were evaluated by 6 radiation therapists, generating 4,015 evaluation points. Statistically significant improvements were observed in CVS and image quality (p < 0.001) with DIBH. Also, the rate of surgical cavity identification increased to 76 % with DIBH compared to 56 % without (p < 0.001). DIBH significantly reduced the inter-observer variability in registration shift corrections (p < 0.001) CONCLUSION: Utilizing DIBH for motion control improves both the image quality and the surgical cavity identification. This results in a decrease in registration variability, which is important for APBI accuracy.

20.
Artículo en Inglés | MEDLINE | ID: mdl-39179918

RESUMEN

PURPOSE: To evaluate Vessel Tracking software for determining the prostatic arteries feeding the prostate gland during prostatic artery embolization (PAE) using Conebeam-CT (CBCT). MATERIALS AND METHODS: EmboGuide is a software developed to assist interventional radiologists in performing embolization of hypervascular tumors in the liver. In this study, a single-center retrospective image collection of 120 intraprocedural CBCT of 60 patients with benign prostatic hyperplasia treated using PAE between May 2017 and January 2019 was evaluated. All patients received 1 intraprocedural CBCT per side for evaluation of vessel anatomy. The "reference standard" of the vascular anatomy was defined by segmentation of the prostatic gland and marking of the prostatic artery in conjunction with pre-embolization DSA series. The datasets were then anonymized. Three interventional radiologists with experience in PAE from different centers reviewed the images and used the automatic feeder detection to determine the prostatic artery. Finally, two clinical experts compared the feeding vessels indicated in the "reference standard" and those identified by the readers. Objectives of the study were to evaluate the clinical performance of the software based on sensitivity and the agreement between interventional radiologists. RESULTS: Sensitivity was estimated as 0.968 with a 90% confidence interval. Overall agreement was estimated as 0.801 with a 90% confidence interval. On both objectives (Sensitivity and Agreement), specifications were met. CONCLUSIONS: The results of this study suggest that EmboGuide can be used to determine the prostate arteries in PAE. The findings could be used to expand the intended use of EmboGuide to include PAE.

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