Tomography, Volume 11, Issue 7 (July 2025) – 9 articles

Background/Objectives: Multiparametric MRI (mpMRI) is widely established as the standard imaging modality for detecting clinically significant prostate cancer (csPCa), yet it can be limited by cost, accessibility, and the need for specialized radiologist interpretation. Micro-ultrasound (micro-US) has recently emerged as a more accessible alternative imaging modality. This review evaluates whether the evidence base for micro-US meets thresholds comparable to those that led to MRI’s guideline adoption, synthesizes diagnostic performance data compared to mpMRI, and outlines future research priorities to define its clinical role. Methods: A targeted literature review of PubMed, Embase, and the Cochrane Library was conducted for studies published between 2014 and May 2025 evaluating micro-US in csPCa detection. Search terms included “micro-ultrasound,” “ExactVu,” “PRI-MUS,” and related terminology. Study relevance was assessed independently by the authors. Extracted data included csPCa detection rates, modality concordance, and diagnostic accuracy, and were synthesized and, rarely, restructured to facilitate study comparisons. Results: Micro-US consistently demonstrated non-inferiority to mpMRI for csPCa detection across retrospective studies, prospective cohorts, and meta-analyses. Several studies reported discordant csPCa lesions detected by only one modality, highlighting potential complementarity. The recently published OPTIMUM randomized controlled trial offers the strongest individual-trial evidence to date in support of micro-US non-inferiority. Conclusions: Micro-US shows potential as an alternative or adjunct to mpMRI for csPCa detection. However, additional robust multicenter studies are needed to achieve the evidentiary strength that led mpMRI to distinguish itself in clinical guidelines. Full article

Background/Objectives: One of the surgical interventions applied in the cervical region is the pedicle screw method. The cervical pedicle screw is stronger than any other screw method; however, use of the cervical pedicle screw is limited due to the variability in the anatomy of the cervical vertebrae and the risks to the neurological and vascular structures in this region. This study aimed to determine the morphological features of subaxial cervical vertebrae of the adult Turkish population and to provide guidance for the pedicle screwing method. Methods: In our study, pedicle analyses were examined in the subaxial neck vertebrae of a total of 60 patients, 30 male and 30 female, using computed tomography images. In subaxial vertebrae (C3–C7), bilateral pedicle width, pedicle axis length, pedicle transverse angle, sagittal and transverse diameter of vertebral foramen, and the distance between two pedicles were measured. Results: Pedicle widths that did not fit the commonly used 3.5 mm pedicle screw were detected in both male and female patients. The mean bilateral pedicle width in male patients was found to be greater than in female patients. When the parameter results were compared according to the levels, it was found that the pedicle width, pedicle axis length, transverse diameter, and the distance between the two pedicles increased statistically significantly. Conclusions: We think that the data obtained from the study will help determine the appropriate screwing (screw selection) in subaxial vertebra pedicle surgery and increase the success of the surgical procedure. Full article

The rapid growth of artificial intelligence, particularly in the field of deep learning, has opened up new advances in analyzing and processing large and complex datasets. Prospects and emerging trends in this area engage the development of methods, techniques, and algorithms to build autonomous systems that perform tasks with minimal human action. In medical practice, radiological imaging technologies systematically boost progress in the clinical monitoring of cancer through the information that can be analyzed in these images. This review gives insight into deep learning-based approaches that strengthen the assessment of the response to the treatment of non-small-cell lung cancer. This systematic survey delves into the various approaches to morphological and metabolic changes observed in computerized tomography (CT) and positron emission tomography (PET) imaging. We highlight the challenges and opportunities for feasible integration of deep learning computer-based tools in evaluating treatments in lung cancer patients, after which CT and PET-based strategies are contrasted. The investigated deep learning methods are organized and described as instruments for classification, clustering, and prediction, which can contribute to the design of automated and objective assessment of lung tumor responses to treatments. Full article

Background: The use of photon-counting detector computed tomography (PCD-CT) has improved image quality in cardiac, pulmonary, and musculoskeletal imaging. Abdominal imaging research, especially about the use of PCD-CT in hepatocellular carcinoma (HCC), is sparse. Objectives: We aimed to compare the image quality of tumors, the liver parenchyma, and the vasculature in patients with HCC using PCD-CT reconstructions at different slice thicknesses and kernels to identify the most appropriate settings for the clinical routine. Methods: CT exams from twenty adult patients with HCC performed with a clinically approved, first-generation PCD-CT scanner (Naeotom Alpha^®, Siemens Healthineers), were retrospectively reviewed. For each patient, images were reconstructed at four different sharp kernels, designed for abdominal imaging (Br40; Br44; Br48; Br56) and at three slice thicknesses (0.4 mm; 1 mm; 3 mm). The reconstruction with the Br40 kernel at 3 mm (Br40_{3 mm}) was used as a clinical reference. Three readers independently assessed the image quality of different anatomical abdominal structures and hypervascular HCC lesions using a five-point Likert scale. In addition, image sharpness was assessed using line-density profiles. Results: Compared with the clinical reference, the Br44_{1 mm} and Br48_{1 mm} reconstructions were rated superior for the assessment of the hepatic vasculature (median difference +0.67 [+0.33 to +1.33], p < 0.001 and +1.00 [+0.67 to +1.67], p < 0.001). Reconstructions for Br40_{1 mm} (+0.33 [−0.67 to +1.00], p < 0.001), and Br44_{3 mm} (+0.0 [0.0 to +1.00], p = 0.030) were scored superior for overall image quality. The noise demonstrated a continuous increase when using sharper kernels and thinner slices than Br40_{3 mm} (p < 0.001), leading to a decrease in contrast-to-noise ratio. Although there was a trend toward increased image sharpness using the slope analysis with higher kernels, this was not significantly different compared with the reference standard. Conclusion: PCD-CT reconstruction Br40_{1 mm} was the most suitable setting for overall image quality, while reconstructions with sharper kernels (Br44_{1 mm} and Br48_{1 mm}) can be considered for the assessment of the hepatic vasculature in patients with HCC. Full article

Background/Objectives: Spread through air spaces (STAS) is defined as the spread of tumor cells into the parenchymal alveolar space beyond the margins of the main tumor, and it is associated with worse clinical outcomes in resected lung adenocarcinoma. This study aimed to evaluate the preoperative computed tomography (CT) findings of primary lung adenocarcinoma in surgically resected T1 cases and to compare CT findings with and without STAS. Methods: A total of 145 patients were included in this study. The following factors were evaluated on CT images: nodule type (pure ground-glass nodule [GGN], part-solid nodule, or solid nodule), margin (smooth or irregular), the presence of lobulation, spicula, cavity, calcification, central low attenuation, peripheral opacity (well-defined or ill-defined), air bronchogram, satellite lesions, pleural retraction, pulmonary emphysema, and interstitial pneumonia; CT values (maximum, minimum, and mean); volume (tumor and solid component); and diameter (tumor and solid component). CT criteria were compared between the presence and absence of STAS. Results: Lobulation and central low attenuation were significantly more frequent in patients with STAS (p < 0.05). The mean CT value, and the volume, rate, and diameter of the solid component were significantly larger in cases with STAS (p < 0.05). A multiple logistic regression analysis identified central low attenuation as an indicator of the presence of STAS (p < 0.001; odds ratio, 3.993; 95% confidence interval, 1.993–8.001). Conclusions: Quantitative and qualitative analyses are useful for differentiating between the presence and absence of STAS. Full article

Background: Extracranial arteriovenous malformations (AVMs) are rare congenital vascular anomalies that often require endovascular treatment due to symptoms such as pain, bleeding, or functional impairment. Endovascular strategies include arterial, venous, or combined embolization approaches; however, recurrence remains a major challenge. We retrospectively evaluate the technical success, safety, and clinical outcomes of arterial-only versus combined arterial and venous embolization for the treatment of extracranial AVMs. Materials and Methods: This single-center retrospective study included 14 patients (mean age 31.8 ± 21.7 years; 64% female) with symptomatic extracranial AVMs (Schobinger stage II) treated between 2017 and 2023. AVMs were classified angiographically (Yakes classification) and treated with embolization via arterial or combined access routes. The primary endpoint was technical success (defined as angiographic nidus occlusion), while secondary endpoints included clinical recurrence and procedure-related complications. Follow-up included clinical and Doppler ultrasound assessments. Results: Nine patients (64%) underwent arterial embolization alone; five (36%) received combined arterial and venous embolization, including Lauromacrogol injection via direct puncture. Technical success was achieved in all cases (100%). Clinical recurrence occurred in two patients (14%), both from the arterial-only group. One major complication (tongue ischemia) occurred in a single patient (7%). No complications or recurrences were observed in the combined treatment group. Statistical analysis showed no significant difference in recurrence or complication rates between groups. Full article

Objective: This ex vivo study aimed to evaluate the influence of different acquisition protocols, combining voxel size and field of view (FOV), across four cone-beam computed tomography (CBCT) systems, on the accuracy of alveolar bone level measurements for periodontal assessment. Materials and Methods: A dry human mandible was used, with standardized radiopaque markers placed on the cementoenamel junction (CEJ) of the buccal–mesial and buccal–distal aspects of teeth 34 and 43. CBCT scans were performed using four systems—Veraview^® X800, OP300 Pro^®, I-CAT Next Generation^®, and Orthophos XG^®—applying various combinations of field of view (FOV) and voxel resolution available in each device. Reference measurements were obtained in situ using a digital caliper. CBCT images were exported in DICOM format and analyzed with OnDemand3D software (version 4.6) to obtain paracoronal sections. Linear measurements from the CEJ to the alveolar crest were recorded in triplicate and compared to the gold standard using ANOVA and the Dunnett test (α = 0.05). Results: Protocols with smaller voxel sizes and limited FOVs generally yielded measurements closer to the gold standard. However, some larger-FOV protocols with intermediate voxel sizes also achieved comparable accuracy. Among the systems, the I-CAT showed lower agreement within in situ measurements, while others demonstrated reliable performance depending on the acquisition parameters. Conclusions: The findings suggest that CBCT protocols with smaller voxel sizes and reduced FOVs can enhance measurement accuracy in periodontal bone assessments. Nevertheless, intermediate protocols may offer a balance between diagnostic quality and radiation exposure, aligning with the ALADA principle. This study reinforces the need for standardized acquisition parameters tailored to periodontal imaging. Full article

Background/Objectives: The relationship between upper trapezius muscle stiffness and choroidal circulatory dynamics remains unclear. This study aimed to examine changes in upper trapezius muscle stiffness and choroidal circulatory dynamics before and after trapezius muscle self-stretching. Methods: Eighteen healthy adults in their 20s (median age ± standard error: 21.0 ± 4.9 years) and eight healthy adults in their 40s (age: 43.0 ± 15.2 years) were included. Intraocular pressure (IOP); systolic, diastolic, and mean blood pressure (BP); heart rate (HR); ocular perfusion pressure (OPP); and salivary alpha-amylase (sAA) activity—as an indicator of autonomic nervous system function—were measured at baseline and after trapezius muscle self-stretching. Upper trapezius muscle stiffness was assessed using ultrasound strain elastography, whereas choroidal circulation was evaluated using laser speckle flowgraphy to determine the mean blur rate (MBR), a relative measure of macular blood flow velocity. Results: Significant reductions in systolic and mean BP; OPP; sAA activity; and MBR were observed after trapezius muscle self-stretching in both groups; however, no significant changes were found in IOP and HR. A significant decrease in upper trapezius muscle stiffness was observed after self-stretching only in the 20-year-old group. Conclusions: In healthy adults in their 20s and 40s, trapezius muscle self-stretching may enhance parasympathetic nervous system activity, resulting in decreased systemic and choroidal circulatory parameters. However, the reduction in muscle stiffness observed only in younger participants suggests that short-term self-stretching may be less effective in reducing trapezius muscle stiffness with advancing age. Full article

Objectives: To evaluate the agreement between AI-CAD-guided mammographic and MRI measurements of tumor size and T stage in breast cancer patients being considered for neoadjuvant chemotherapy (NAC). Methods: This retrospective study included 144 women (mean age, 52 ± 11 years) with invasive breast cancer who subsequently received NAC and underwent both AI-CAD mammography (score ≥ 10) and pre-treatment MRI. Tumor sizes from AI-CAD contours were compared with MRI using Pearson correlation, intraclass correlation coefficients (ICCs), and Bland–Altman analysis. Concordance was defined as a ±0.5 cm difference. The contour showing the highest agreement was used to compare T stage with MRI using weighted kappa. Results: The mean AI-CAD abnormality score was 86.3 ± 22.2. Tumor sizes on mammography were 3.0 ± 1.2 cm (inner), 3.8 ± 1.5 cm (middle), and 4.8 ± 2.2 cm (outer), while the MRI-measured tumor size was 4.0 ± 1.9 cm. The middle contour showed the strongest correlation with MRI (r = 0.897; ICC = 0.866), the smallest mean difference (–0.19 cm; limits of agreement, –1.87 to 1.49), and the highest concordance (61.1%). Agreement was higher in mass-only lesions than in NME-involved lesions (ICC = 0.883 vs. 0.775; concordance, 70.9% vs. 46.6%). T stage comparison using the middle contour showed substantial agreement with MRI (κ = 0.743 [95% CI, 0.634–0.852]; agreement, 88.2%), with higher concordance in mass-only lesions (93.0%) than NME-involved lesions (81.0%) and more frequent understaging in the latter (17.2% vs. 2.3%). Conclusions: AI-CAD-guided mammographic assessment using the middle contour demonstrated good agreement with MRI for tumor size and T stage, indicating its value as a supportive tool for clinical staging in MRI-limited settings. Full article