Cone-beam Computed Tomography Images Research Articles

Comparative Analysis of Impacted Mandibular Third Molar Root Proximity to the Mandibular Canal using Orthopantomography and Cone-beam Computed Tomography Imaging Modalities: A Pilot Study

Abstract Introduction: Fully detect risks of nerve damage, which can lead to temporary or permanent issues. Cone-beam computed tomography (CBCT) offers a three-dimensional (3D) view, providing more detailed visualisation of anatomical structures and their spatial relationships, which improves the accuracy of predicting nerve exposure. The study aims to evaluate and compare these imaging techniques’ effectiveness in categorising the relationship between third molars and the inferior alveolar canal, emphasising the importance of precise imaging for safer surgical outcomes. Materials and Methods: A pilot study involving 20 patients, representing 10% of the total sample size of 200, was conducted at Ahmedabad Dental College’s Department of Oral Medicine and Radiology. Investigators, trained to interpret radiological images from orthopantomography (OPG) and CBCT, compared their interpretations with those of two experts. A high inter-rater reliability was confirmed with a kappa statistic of 0.98. Following ethical approval, data were retrospectively collected from 20 cases, with digital OPG and CBCT images analysed and classified according to established criteria. Results: The results revealed a significant association between the results diagnosed through OPG and CBCT indicating similarity in their diagnosis. It was also seen that there was no bias towards the gender and the distribution was similar in case of diagnosis through OPG or CBCT. Conclusion: CBCT demands an in-depth understanding of anatomy and pathology, coupled with proficiency in operating imaging software and the ability to identify abnormalities in cross-sectional images. When executed and interpreted accurately, CBCT proves to be an exceptionally valuable tool in clinical dental practice. Its detailed 3D imaging capabilities enhance the assessment of complex cases, such as those involving intricate anatomical structures and pathologies. By providing comprehensive views that surpass traditional two-dimensional imaging, CBCT aids in precise diagnosis and treatment planning, making it an indispensable resource for addressing various dental conditions effectively.

Pulp calcification identification on cone beam computed tomography: an artificial intelligence pilot study

BackgroundThis study aims to verify the effectiveness of a deep neural network (DNN) in automatically identifying pulp calcification on cone beam computed tomography (CBCT) images.MethodsThis study retrospectively analysed 150 CBCT images. Pulp calcification was identified and manually annotated by three endodontists with 10 years of experience. A DNN model based on the U-Net architecture was constructed to identify pulp calcification, and ten rounds of fourfold cross-validation were conducted. The model performance was evaluated using sensitivity, specificity, accuracy, and the area under the receiver operating characteristic curve (AUC).ResultsThe model achieved a sensitivity of 75.91 ± 2.84% in automatically identifying pulp calcification, with a specificity of 68.88 ± 2.35%, an accuracy of 72.78 ± 2.13%, and an AUC of 73.68 ± 3.09%. According to the ranking for diagnostic tests, the proposed method achieved a “good” grade for sensitivity, accuracy, and AUC and a “fair” grade for specificity.ConclusionsThe results indicate that the proposed method shows promise for identifying pulp calcification on CBCT images. Future research aims to expand the dataset and refine the model, thereby enhancing its clinical applicability. The integration of artificial intelligence into diagnostic and treatment systems is anticipated to increase the efficiency of diagnosing pulp calcification and assist dentists in assessing the difficulty of root canal treatment cases preoperatively.Clinical registrationRegistration was performed on the Chinese Clinical Trial Registry (https://www.chictr.org.cn/) (Registration number: ChiCTR2300077078, 27/10/2023) and National Medical Research Registry Information System (https://www.medicalresearch.org.cn/, 30/10/2023) (Number: MR-44–23-039664).

Assessment of the Trabecular Bone Microstructure Surrounding Impacted Maxillary Canines Using Fractal Analysis on Cone-Beam Computed Tomography Images.

To assess the impact of the presence or position (buccal/palatal) of impacted canines on trabecular bone density using fractal analysis (FA) on cone-beam computed tomography (CBCT) images, and to compare the results with a control group without impacted canines. This retrospective study included 41 patients with unilateral impacted canines (30 palatal, 11 buccal) and a control group of 39 patients who underwent surgically assisted rapid maxillary expansion. All patients had CBCT images recorded for diagnostic and treatment purposes. Cross-sectional CBCT images were obtained between the first and second premolars on both sides of the patients' maxilla. From these images, fractal dimension (FD) was measured in a 20 × 20 pixel region of interest in the trabecular bone using the ImageJ software. The FD values were significantly higher on the impacted side in the impacted canine group (p = 0.02). Within the impacted canine group, a significant increase in FD was observed on the impacted side in the buccal-impacted subgroup (p = 0.02), while no significant difference was observed in the palatal-impacted subgroup (p > 0.05). According to the results of our study, there is an association between the position of the impacted canine and trabecular bone density. An increased trabecular bone density may play a role in the etiology of buccally impacted canines. Clinicians should consider anchorage planning, and appropriate force level, during the forced eruption of buccally impacted canines with high surrounding bone density, to minimize undesirable movements and achieve optimal treatment outcomes.

The short-term postoperative pain and impact upon quality of life of pulpotomy and root canal treatment, in teeth with symptoms of irreversible pulpitis: A randomized controlled clinical trial.

Few studies focus upon patient-reported outcomes in endodontics. To determine whether full pulpotomy offers a less painful, improved health-related quality of life (HRQoL) compared with root canal treatment (RCT) in cases of irreversible pulpitis (IP) in the 7 days after the treatment. One hundred sixty-eight participants presenting with symptoms of IP were randomized to either pulpotomy (n = 86) or RCT (n = 82). Two participants were excluded, 61 participants underwent full pulpotomy with Biodentine (35.7%), 80 had RCT (46.8%), and 25 were randomized to have pulpotomy which progressed to RCT (PRCT) due to uncontrollable bleeding (14.6%). Clinical and radiographic assessments, using CBCT and periapical radiographs, were carried out preoperatively, for the evaluation of the results only CBCT images were used. Pain (VAS) and HRQoL (EQ 5D) assessments were carried out at baseline and Days 1, 3, 5 and 7 post-baseline. Analysis included descriptive and continuous variables, chi-squared, Fisher's exact, and two-sample t-tests. In pulpotomy and RCT groups, VAS pain decreased significantly over the first week (p < .001). The magnitude of reduction was similar in RCT and pulpotomy (p = .804), RCT and PRCT (p = .179), pulpotomy vs. PRCT (p = .144) and in the comparison of combined RCT /PRCT groups (ORCT) with Pulpotomy (0.729). However, the overall level of VAS pain was significantly higher in the PRCT group than in the Pulpotomy (p = .045) and RCT group (p = .049). Using CBCT, significantly more radiolucencies were found in the PRCT group than in the pulpotomy group and overall teeth presenting with CBCT radiolucencies had significantly higher pain scores (p = .015), particularly at Days 1, 3 and 5. There were significant differences in many OHRQoL domains (Questions 1, 6, 11 and 12) between RCT and PRCT groups with higher frequencies of the impact of oral health problems at Day 0 and Day 7 in the PRCT group. In the treatment of IP, pulpotomy is as effective as RCT in reducing post-operative pain, and improving QoL and HRQoL, teeth displaying uncontrollable bleeding and periapical radiolucencies detected using CBCT are associated with more intense postoperative pain and lower QoL.

Comparative Assessment of Pharyngeal Airway Dimensions in Skeletal Class I, II, and III Emirati Subjects: A Cone Beam Computed Tomography Study.

The aim of the current study was to evaluate the pharyngeal airway dimensions of individuals with different skeletal patterns in a cohort of the Emirati population. The specific aim was to assess the relationship between pharyngeal airway dimensions and anterior facial height in relation to different skeletal patterns. This retrospective study was conducted on a sample of 103 CBCT scans of adult Emirati subjects categorized into three groups according to their skeletal classification as indicated by the ANB angle: Class I (n = 35), Class II (n = 46), and Class III (n = 22). All CBCT scans were taken using an i-CAT CBCT imaging machine (Imaging Sciences, Hatfield, PA, USA). The age range of the patients was 19 to 68 years (62 women and 41 men). ANOVA, t-tests, Kruskal-Wallis, and Mann-Whitney tests were employed for comparing means among groups. The correlation coefficient was used to evaluate the association between variables. A p-value of less than 0.05 was considered statistically significant. This study revealed significant associations between various airway parameters and cephalometric measurements. Positive correlations were observed between nasal cavity volume and nasopharynx volume, as well as anterior facial height. Oropharynx volume exhibited positive correlations with hypopharynx volume and total airway volume, and negative correlations with overjet, ANB angle, and patient age. Hypopharynx volume correlated positively with total airway volume and the most constricted area of the airway (MCA). Total airway volume showed positive correlations with MCA and anterior facial height. MCA had negative correlations with ANB angle and patient age. Nasopharynx volume was significantly larger in the skeletal Class I group than in the Class II or Class III groups, while the other airway parameters showed no significant differences among the groups (p > 0.05). Several airway parameters showed a correlation with anterior facial height among the different skeletal patterns. Nasopharyngeal airway volume was significantly larger in the skeletal Class I group than in Class II and III groups in the studied sample.

Finite element analysis of non-ultraviolet and ultraviolet-irradiated titanium implants.

The purpose of this study is to calculate von Mises stresses, von Mises strains, deformation, principal stresses and principal elastic strains of non-UV and UV-irradiated hybrid SLA (sandblasted, large-grit, acid-etched)-coated titanium implants. A cross-sectional analytical study was conducted at the Institute of Dentistry, CMH Lahore Medical College. Cone beam computed tomography (CBCT) data of One Hundred and Thirty Eight Dio Hybrid sandblasted and acid-etched implants of identical dimensions (10mm in length and 4.5mm in diameter) were allocated in the three groups. Control group A samples were not given UV irradiation, while groups B and C were given UVA (382nm, 25 mWcm-2) and UVC (260nm, 15 mWcm-2) irradiation, respectively. The CBCT data were analyzed using FEA (ANSYS software). CBCT images were taken before functional loading (8thweek) and after functional loading (26thweek). A 3-way ANOVA test was employed to see the difference between the three groups. Tukey test was utilized for multiple comparisons. p ≤ 0.05 was considered significant. The control group exhibited the highest average values for maximum von Mises stress, von Mises strain, deformation, principal stress, and principal elastic strain in both the maxilla and mandible compared to the UV-irradiated groups. Additionally, these measures consistently displayed higher averages in the maxilla across all groups compared to the mandible. Particularly, the UVC-irradiated group demonstrated the lowest von Mises stresses around the implants compared to the UVA group. Insignificant differences were observed between UVA- and UVC-irradiated implants in terms of principal stress, deformation, von Mises strain, and principal elastic strain. The only notable distinction was in von Mises stress, where the UVC-irradiated group exhibited lower von Mises stress around SLA-coated titanium implants.

Measurement of Anterior Maxillary Alveolar Ridge Dimension and Assessment of Sagittal Root Position by Cone Beam Computerized Tomography (CBCT)

Maxillary anterior region is the implant site that may require the most rigorous pre-operative assessment as it will have a direct influence on aesthetic outcome and stability of the dental implant. In the present study, CBCT (cone beam computerized tomography) images were used to evaluate alveolar ridge dimension in the maxillary anterior region. This observational radiographic study was done at Nepal Medical College Teaching Hospital. The width of the alveolar bone was measured from the labial cortex to the palatal cortex of the maxillary anterior teeth in mm at the alveolar crest (L1), mid-root (L2), and apical root region (L3) for each tooth. Alveolar height was also measured from the alveolar crest to the floor of the nasal fossa. The Sagittal Root Position (SRP) of the maxillary anterior teeth was also assessed. Results showed that the maximum width of the alveolar bone was seen at L3 of canine and lateral incisor showed least width of alveolar bone width at L1. Maximum alveolar bone height was seen in canines. Males were seen to have increased width of the alveolar bone as compared to the females in all anterior teeth. The most frequent sagittal root position was class I which was seen in 270 (51.4%) of the total teeth examined, which was followed by class IV observed in 210 (40%) of the teeth examined. It could be concluded that for maxillary anterior region, additional regeneration therapy maybe required since class I is the most frequent SRP observed.

Evaluation and Comparison of Dentin Thickness, Centering Ability, Canal Transportation, and Instrumentation Time of Pro AF Baby Gold and Pedoflex Files in Primary Root Canals Using a Cone Beam Computed Tomographic Analysis: An In Vitro Study.

Pediatric rotary systems have the advantage of improved canal centricity and conservative canal preparation with better obturation quality. Pro AF Baby Gold and Pedoflex files are two exclusive pediatric rotary file systems that were introduced in recent times. The aim of the present study is to compare and evaluate the dentine thickness, centering ability, canal transportation, and instrumentation time of Pro AF Baby Gold and Pedoflex files using cone beam computed tomography (CBCT). A total of 40 extracted human primary molar teeth with a minimum 7 mm root length were included in the study and randomly divided into two groups: group I, Pro AF Baby Gold; group II, Pedoflex files. Teeth were imaged preoperatively with CBCT, then root canal preparation was done in both groups with respective files, followed by postoperative CBCT imaging to evaluate the dentin thickness, centering ability, and canal transportation of both groups. Instrumentation time was noted using a stopwatch. There is a statistically significant difference in the instrumentation time; Pedoflex took a shorter time when compared to Pro AF Baby Gold files. Regarding canal transportation, there was no significant difference between the two files, with Pedoflex showing a better value than the other files. Regarding centering ability, there was no significant difference between the two files, with Pro AF Baby Gold having a better value than the other files (p < 0.001). From the findings of our present study, it was found that both systems were able to effectively shape curved root canals in terms of canal transportation and centering ability. Busi S, PJ N, Deoghare A, et al. Evaluation and Comparison of Dentin Thickness, Centering Ability, Canal Transportation, and Instrumentation Time of Pro AF Baby Gold and Pedoflex Files in Primary Root Canals Using a Cone Beam Computed Tomographic Analysis: An In Vitro Study. Int J Clin Pediatr Dent 2024;17(8):892-897.

Optimal Training Positive Sample Size Determination for Deep Learning with a Validation on CBCT Image Caries Recognition.

Objectives: During deep learning model training, it is essential to consider the balance among the effects of sample size, actual resources, and time constraints. Single-arm objective performance criteria (OPC) was proposed to determine the optimal positive sample size for training deep learning models in caries recognition. Methods: An expected sensitivity (PT) of 0.6 and a clinically acceptable sensitivity (P0) of 0.5 were applied to the single-arm OPC calculation formula, yielding an optimal training set comprising 263 carious teeth. U-Net, YOLOv5n, and CariesDetectNet were trained and validated using clinically self-collected cone-beam computed tomography (CBCT) images that included varying quantities of carious teeth. To assess performance, an additional dataset was utilized to evaluate the accuracy of caries detection by both the models and two dental radiologists. Results: When the number of carious teeth reached approximately 250, the models reached the optimal performance levels. U-Net demonstrated superior performance, achieving accuracy, sensitivity, specificity, F1-Score, and Dice similarity coefficients of 0.9929, 0.9307, 0.9989, 0.9590, and 0.9435, respectively. The three models exhibited greater accuracy in caries recognition compared to dental radiologists. Conclusions: This study demonstrated that the positive sample size of CBCT images containing caries was predictable and could be calculated using single-arm OPC.

Condylar Remodeling and Skeletal Changes Following Occlusal Splint and Manual Therapy: A Cone Beam Computed Tomography Study in Temporomandibular Disorders.

Background: Temporomandibular disorders (TMD) may be associated with degenerative disease of temporomandibular joint (TMJ), such as condyle erosion and subchondral cysts. Occlusal splint and cranio-mandibular manual therapy, or combined therapy, is recommended as a conservative treatment to alleviate pain-related signs and symptoms in TMD. This study aimed to assess osseous condylar changes and skeletal changes following occlusal splint and cranio-mandibular manual therapy in TMD using cone beam computed tomography (CBCT). Methods: A retrospective cohort study included 24 patients diagnosed with TMD. Combined therapy was performed until pain-related signs and symptoms disappeared. CBCT scans were performed before and after therapy. Osseous structure of condyles and their subsequent modifications were analyzed on CBCT images: flattening, erosion, and subchondral cyst. Sella-Nasion-A point (SNA), Sella-Nasion-B point (SNB), A point-Nasion-B point (ANB), Sella-Articulare-Gonion (Condylar angle), and anterior and posterior facial height (AFH, PFH) were measured on CBCT-generated lateral cephalograms. A paired t-test, Wilcoxon rank-sum test, McNemar test, and Stuart-Maxwell test were used for the statistical analyses. Results: The treatment period with combined therapy was 7.42 ± 3.27 months, and 21 out of 33 TMJ presenting degenerative disease (63.6%) had significant complete remodeling (p < 0.05). Following therapy, SNB significantly decreased from 75.61 ±3.47° to 74.82 ± 3.41° (p = 0.02), ANB significantly increased from 4.05° (3.35-4.9°) to 4.8° (3.3-6.12°) (p < 0.001), AFH significantly increased from 112.85 mm (109.28-118.72) to 115.3 mm (112.58-118.88) (p < 0.001), PFH/AFH significantly decreased from 64.17 (61.39-66.1) to 63 (59.68-64.51) (p = 0.012), and condylar angle significantly increased from 140.84 ± 8.18° to 144.42 ± 8.87° (p = 0.007). Conclusion: Combined therapy promoted significant condylar remodeling in TMJ degenerative disease, along with skeletal changes (mandibular retrusion and increase in facial height). Therapeutic strategies should consider condylar remodeling in TMD. Skeletal and dental parameters should be evaluated prior to occlusal splint therapy.

Pseudo‐CT synthesis in adaptive radiotherapy based on a stacked coarse‐to‐fine model: Combing diffusion process and spatial‐frequency convolutions

AbstractBackgroundCone beam computed tomography (CBCT) provides critical anatomical information for adaptive radiotherapy (ART), especially for tumors in the pelvic region that undergo significant deformation. However, CBCT suffers from inaccurate Hounsfield Unit (HU) values and lower soft tissue contrast. These issues affect the accuracy of pelvic treatment plans and implementation of the treatment, hence requiring correction.PurposeA novel stacked coarse‐to‐fine model combining Denoising Diffusion Probabilistic Model (DDPM) and spatial‐frequency domain convolution modules is proposed to enhance the imaging quality of CBCT images.MethodsThe enhancement of low‐quality CBCT images is divided into two stages. In the coarse stage, the improved DDPM with U‐ConvNeXt architecture is used to complete the denoising task of CBCT images. In the fine stage, the deep convolutional network model jointly constructed by fast Fourier and dilated convolution modules is used to further enhance the image quality in local details and global imaging. Finally, the accurate pseudo‐CT (pCT) images consistent with the size of the original data are obtained. Two hundred fifty paired CBCT‐CT images from cervical and rectal cancer, combined with 200 public dataset cases, were used collectively for training, validation, and testing.ResultsTo evaluate the anatomical consistency between pCT and real CT, we have used the mean(std) of structure similarity index measure (SSIM), peak signal to noise ratio (PSNR), and normalized cross‐correlation (NCC). The numerical results for the above three metrics comparing the pCT synthesized by the proposed model against real CT for cervical cancer cases were 87.14% (2.91%), 34.02 dB (1.35 dB), and 88.01% (1.82%), respectively. For rectal cancer cases, the corresponding results were 86.06% (2.70%), 33.50 dB (1.41 dB), and 87.44% (1.95%). The paired t‐test analysis between the proposed model and the comparative models (ResUnet, CycleGAN, DDPM, and DDIM) for these metrics revealed statistically significant differences (p &lt; 0.05). The visual results also showed that the anatomical structures between the real CT and the pCT synthesized by the proposed model were closer. For the dosimetric verification, mean absolute error of dosimetry (MAEdoes) values for the maximum dose (Dmax), the minimum dose (Dmin), and the mean dose (Dmean) in the planning target volume (PTV) were analyzed, with results presented as mean (lower quartile, upper quartile). The experimental results show that the values of the above three dosimetry indexes (Dmin, Dmax, and Dmean) for the pCT images synthesized by the proposed model were 0.90% (0.48%, 1.29%), 0.82% (0.47%, 1.17%), and 0.57% (0.44%, 0.67%). Compared with 10 cases of the original CBCT image by Mann–Whitney test (p &lt; 0.05), it also proved that pCT can significantly improve the accuracy of HU values for the dose calculation.ConclusionThe pCT synthesized by the proposed model outperforms the comparative models in numerical accuracy and visualization, promising for ART of pelvic cancers.

Metal artifact reduction tool and mA levels impact on the diagnosis of fracture extension in endodontically treated teeth using cone-beam CT.

To evaluate the influence of different levels of metal artifact reduction (MAR) tool and milliamperage (mA) on the diagnosis of fracture extension in endodontically treated teeth using cone beam CT (CBCT). Ten maxillary premolars were endodontically treated and positioned in the empty sockets of a human maxilla covered with wax. CBCT acquisitions were performed using the Eagle Edge device (Dabi Atlante, Brazil) adjusted to 120 kVp, FOV of 4 × 6cm, exposure time of 24s and voxel size of 0.2mm in 8 different conditions with different MAR (1, 2 and 3) and mA (3.2 and 6.3) levels. Crown-root fractures were simulated in the universal testing machine, and CBCT images were acquired again. Five radiologists evaluated the presence and extension of fractures with a 5-point scale. Statistical analysis was performed by analysis of variance, Tukey and Kappa test (α = 0.05). Although different mA levels did not significantly (p > 0.05) affect the diagnosis values for fracture presence and extension, when evaluated the different levels of MAR, AUC and sensitivity showed significantly higher values (p < 0.05) for MAR 0 using 6.3mA and kappa agreement showed significantly higher values (p < 0.05) for MAR 0 and 2 using 6.3mA. Although mA levels do not have a diagnostic effect when isolating the MAR level; in 6.3mA, MAR 0 and 2 can positively influence the diagnosis of fracture extension in endodontically treated teeth using CBCT. The isolate evaluation of dental fracture presence can overlook diagnostics error of its extension.

Evaluation of Sphenoid Sinus Variations in Cleft Lip and Palate Patients: A Comprehensive Cone Beam Computed Tomography Analysis.

This study aims to compare sphenoid sinus variations between unilateral and bilateral cleft lip and palate (CLP) patients and healthy controls using CBCT images. It is notable for its large sample size and comparison of unilateral and bilateral cleft patients, cleft and noncleft sides, and different age groups. Retrospective cohort study. University Hospital. CBCT images of 97 CLP patients (76 unilateral, 21 bilateral) and 97 healthy controls were evaluated.Main Outcome Measures: Sphenoid sinus main types, sellar subtypes, clival, and lateral extensions were assessed for all groups. A significant increase in the anterior type was observed in both unilateral and bilateral CLP groups. The bilateral CLP group had a higher prevalence of the lesser wing type. In CLP and control groups, lesser wing, combined type, and lateral type were statistically significantly lower under 13 years of age. The study highlights an elevated prevalence of anterior pneumatization in unilateral and bilateral CLP individuals, emphasizing its significance in surgery planning due to proximity to critical structures like the optic nerve and sphenopalatine artery. The increased prevalence of the lesser wing type in bilateral CLP patients requires extra caution during anterior clinoidectomy. Lower pneumatization rates in CLP patients under 13 suggest their sphenoid sinus development is similar to that of healthy individuals. Understanding these variations is crucial for appropriate surgical planning and avoiding complications during transsphenoidal surgery.

Detection of hepatocellular carcinoma feeding vessels: MDCT angiography with 3D reconstruction versus digital subtraction angiography

BackgroundAccurate detection of Hepatocellular carcinoma (HCC) feeding vessels during transcatheter arterial chemoembolization (TACE) is important for an effective treatment, while limiting non-target embolization. This study aimed to investigate the feasibility and accuracy of pre-TACE three dimensional (3D) CT angiography for tumor-feeding vessels detection compared to DSA.MethodsSixty-nine consecutive patients referred for TACE from May 2022 to May 2023 were included. (3D) CT images were reconstructed from the pre-TACE diagnostic multiphasic contrast enhanced CT images and compared with non-selective digital subtraction angiography (DSA) images obtained during TACE for detection of HCC feeding vessels. A “Ground truth” made by consensus between observers after reviewing all available pre-TACE CT images, and DSA and CBCT images during TACE to detect the true feeding vessels was the gold standard. Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), accuracy and ROC curve with AUC were calculated for each modality and compared.ResultsA total of 136 active HCCs were detected in the 69 consecutive patients included in the study. 185 feeding arteries were detected by 3D CT and DSA and included in the analysis. 3D CT detection of feeding arteries revealed mean sensitivity, specificity, PPV, NPV and accuracy of 91%, 71%, 98%, 36%, and 90%, respectively, with mean AUC = 0.81. DSA detection of feeding arteries revealed mean sensitivity, specificity, PPV, NPV, and accuracy of 80%, 58%, 96.5%, 16.5% and 78%, respectively, with mean AUC = 0.69.ConclusionsPre-TACE 3D CT angiography has shown promise in improving the detection of HCC feeding vessels compared to DSA. However, further studies are required to confirm these findings across different clinical settings and patient populations.Trial registrationThis study was prospectively registered at Clinicaltrials.gov with ID NCT05304572; Date of registration: 2-4-2022.

Evaluation of a Metal Artifact Reduction Algorithm for Image Reconstruction on a Novel CBCT Platform.

The presence of metal implants can produce artifacts and distort Hounsfield units (HU) in patient computed tomography (CT) images. The purpose of this work was to characterize a novel metal artifact reduction (MAR) algorithm for reconstruction of CBCT images obtained by the HyperSight imaging system. Three tissue-equivalent phantoms were fitted with materials commonly used in medical applications. The first consisted of a variety of metal samples centered within a solid water block, the second was an Advanced Electron Density phantom with metal rods, and the third consisted of hip prostheses positioned within a water tank. CBCT images of all phantoms were acquired and reconstructed using the MAR and iCBCT Acuros algorithms on the HyperSight system. The signal-to-noise ratio (SNR), artifact index (AI), structural similarity index measure (SSIM), peak signal-to-noise ratio (PSNR), and mean-square error (MSE) were computed to assess the image quality in comparison to artifact-free reference images. The mean HU at various VOI positions around the cavity was calculated to evaluate the artifact dependence on distance and angle from the center of the cavity. The artifact volume of the phantom (excluding the cavity) was estimated by summing the volume of all voxels with HU values outside the 5th and 95th percentiles of the phantom CBCT with no artifact. The SNR, AI, SSIM, PSNR, and MSE metrics demonstrated significantly higher similarity to baseline when using MAR compared to iCBCT Acuros for all high-density materials, except for aluminum. Mean HU returned to expected solid water background at a shorter distance from metal sample in the MAR images, and the standard deviation remained lower for the MAR images at all distances from the insert. The artifact volume decreased using the novel MAR algorithm for all metal samples excluding aluminum (p<0.001) and all hip prostheses (p<0.05). Varian's HyperSight MAR reconstruction algorithm shows a reduction in metal artifact metrics, motivating the use of MAR reconstruction for patients with metal implants.

New findings on clinical experience on surface-guided radiotherapy for frameless non-coplanar stereotactic radiosurgery treatments.

The aim of this study was to assess the accuracy of a surface-guided radiotherapy (SGRT) system for setup and intra-fraction motion control in frameless non-coplanar stereotactic radiosurgery (fSRS) using actual patient data immobilized with two different types of open-faced masks and employing a novel SGRT systems settings. Forty-four SRS patients were immobilized with two types of open-faced masks. Sixty lesions were treated, involving the analysis of 68 cone-beam scans (CBCT), 157 megavoltage (MV) images, and 521 SGRT monitoring sessions. The average SGRT translations/rotations and 3D vectors (MAG-Trasl and MAG-Rot) were compared with CBCT or antero-posterior MV images for 0° table or non-coplanar beams, respectively. The intrafraction control was evaluated based on the average shifts obtained from each monitoring session. To assess the association between the SGRT system and the CBCT, the two types of masks and the 3D vectors, a generalized estimating equations (GEE) regression analysis was performed. The Wilcoxon singed-rank test for paired samples was performed to detect differences in couch rotation with longitudinal (LNG) and lateral (LAT) translations and/or yaw. The average SGRT corrections were smaller than those detected by CBCT (≤0.5mm and 0.1°), with largest differences in LNG and yaw. The GEE analysis indicated that the average MAG-Trasl, obtained by the SGRT system, was not statistically different (p=0.09) for both mask types, while, the MAG-Rot was different (p=0.01). For non-coplanar beams, the Wilcoxon singed-rank test demonstrated no significantly differences for the corrections (LNG, LAT, and yaw) for any table rotation except for LNG corrections at 65° (p=0.04) and 75° (p=0.03) table angle position; LAT shifts at 65° (p=0.03) and 270° (p<0.001) table angle position, and yaw rotation at 30° (p=0.02) table angle position. The average intrafraction motion was<0.1mm and 0.1° for any table angle. The SGRT system used, along with the novel workflow performed, can achieve the setup and intra-fraction motion control accuracy required to perform non-coplanar fSRS treatments. Both masks ensure the accuracy required for fSRS while providing a suitable surface for monitoring.

Root canal morphology of mandibular anterior permanent teeth in Turkish sub-population using two classification systems: a cone-beam computed tomography study.

This study examined the root and canal morphology of mandibular anterior teeth (MA) in the Turkish sub-population using cone-beam computed tomography (CBCT), comparing the findings based on Vertucci's and Ahmed et al. classification systems. The CBCT images were acquired using the 3D Accuitomo CBCT device. Images that were deemed suitable for visualizing the roots, canals, and the complete pulp chamber and apex were included in the study. Vertucci and Ahmed et al. classification systems were employed to determine the root canal morphology. 500 CBCT images and 3000 teeth were analyzed. Type I (1MA1) was the most frequent, followed by Type III (1MA1-2-1). 3.8% of teeth could not be classified with Vertucci system. In canine teeth, Vertucci type III (1MA1-2-1) was significantly more prevalent in males than females (p = 0.038) and Type I (1MA1) was less frequent in individuals aged 41-50 (p < 0.05). Canal divergence/merging was the most common at the middle/apical level for central (15.5%) and lateral (10.3%) teeth, and at the coronal/middle level for canine teeth (1.9%). Bilateral similarity was high for all tooth groups (> 78%). One-third of mandibular incisor teeth have two canals, with a significant number exhibiting canal divergence/merging that was separated in the middle region and merged in the apical region. The Vertucci classification was found to be inadequate in some cases, while Ahmed et al. classification was able to classify all mandibular incisors with a single code. Ahmed et al. classification is a more useful system for classifying all MA.

Clinical implementation and evaluation of stereotactic liver radiotherapy in inspiration breath-hold using nasal high flow therapy and surface guidance.

To evaluate two years of clinical experience with markerless breath-hold liver stereotactic radiotherapy (SBRT) using non-invasive nasal high flow therapy (NHFT) for breath-hold prolonging and surface guidance (SGRT) for monitoring. Heated and humidified air was administered via a nasal cannula (40 L/min, 80% oxygen, 34 °C). Patients performed voluntary inspiration breath-holds with visual feedback. After a training session, 4-5 breath-hold CT scans were acquired to delineate an internal target volume (ITV) accounting for inter- and intra-breath-hold variations. Patients were treated in 3-8 fractions (7.5-20 Gy/fraction) using SGRT-controlled beam-hold. Patient setup was performed using SGRT and CBCT imaging. A post-treatment CBCT was acquired for evaluation purposes. Fifteen patients started the training session and received treatment, of whom 10 completed treatment in breath-hold. Half of all 60-second CBCT scans were acquired during a single breath-hold. The average maximum breath-hold duration during treatment ranged from 47-108 s. Breath-hold ITV was on average 6.5 cm³/30% larger (range: 1.1-23.9 cm³/5-95%) than the largest GTV. Free-breathing ITV based on 4DCT scans was on average 16.9 cm³/47% larger (range: -2.3-58.7 cm3/-16-157%) than the breath-hold ITV. The average 3D displacement vector of the area around PTV for the post-treatment CBCT scans was 5.0 mm (range: 0.7-12.9 mm). Liver SBRT in breath-hold using NHFT and SGRT is feasible for the majority of patients. An ITV reduction was observed compared to free-breathing treatments. To further decrease the PTV, internal anatomy-based breath-hold monitoring is desired. Non-invasive NHFT allows for prolonged breath-holding during surface-guided liver SBRT.

Frequency, localization, and diameter of the accessory maxillary ostium and its relationship with sinus pathologies and nasal cavity variations: an anatomical study based on cone beam computed tomography.

The aim of the present study was to determine the presence, frequency, and characteristics of the accessory maxillary ostium (AMO) in a specific Turkish population using cone beam computed tomography (CBCT) and to evaluate the frequency of pathologies and anatomical variations in the nasal cavity and maxillary sinus and to assess their relationship with the AMO. This study retrospectively evaluated the presence of AMO in CBCT images of 543 patients, the patients' age, gender, and dentition status, the presence of nasal cavity variations and maxillary sinus pathologies, and their relationship to the presence of AMO. Descriptive values of the data and comparative results were included. 249 males and 294 females participated in the study. The majority of right and left sinus pathologies were irregular type mucosal thickenings (right/left; 14%, 14.9%). The majority of nasal variations were concha bullosa (right/left; 37.9%, 39.2%). There were 148 (27.3%) and 138 (25.4%) AMOs on the right and left sides, respectively, with the majority in the middle position (right/left; 21.2%/17.5%). The frequency of right and left AMOs was significantly higher in men (P = 0.019 and P = 0.020, respectively). The left AMO frequency was significantly higher in patients with left-sided sinus pathology (P = 0.003). AMO diameters were larger in men (right/left P = 0.010 and P = 0.021, respectively), and left AMO diameter was significantly larger in patients with left sinus pathology (P = 0.006). Before any surgical intervention in the maxillary sinus and osteomeatal region, the presence and location of the AMO, existing pathologies, and variations in the region should be carefully checked to avoid complications.

Morphology and morphometry of the greater palatine foramen: A radio‐anatomical study using cone‐beam computed tomography

AbstractObjectiveThe aim of this study was to evaluate the morphology and morphometry of the greater palatine foramen (GPF) using cone‐beam computed tomography (CBCT).Materials and MethodsThis study included 300 CBCT images and a total of 600 GPFs were evaluated bilaterally. GPF morphology was categorised as round, antero‐posteriorly elongated (APE), or latero‐medially elongated (LME). The distance of GPF relative to the palatine suture (PS), the incisive foramen (IF), and the palatine alveolar ridge (PAR), the distance between the right GPF (GPFr) and left GPF (GPFl) and the angle formed by GPF, IF, and PS were evaluated. The GPF location was also assessed in reference to the maxillary molars.Results64.1% of total GPFs were APE in shape. Male patients presented higher GPF‐related linear and angular measurements on both sides (p &lt; 0.05). Patients aged ≥25 years had larger distances between GPFr–PS, GPFl–PS, GPFr–GPFl, and GPFl–IF (p = 0.001, p = 0.009, p &lt; 0.001, and p = 0.048, respectively; p &lt; 0.05). Patients aged ≤24 years showed a larger distance between GPFl–PAR (p = 0.011; p &lt; 0.05). The distance between GPFl–IF was larger compared to the distance between GPFr–IF, but the angle between GPFr–IF–PS was larger than the angle between GPFl–IF–PS (p = 0.043 and p = 0.004, respectively; p &lt; 0.05). 64.83% of all GPFs were located opposite the maxillary third molar.ConclusionThe shape and location of the GPF exhibit considerable variability. CBCT is a valuable diagnostic modality for assessing anatomical differences in the GPF.