Objectives: The purpose of this study was to evaluate image quality and diagnostic performance of deep learning-based virtual contrast-enhanced (VCE) images generated from photon-counting CT (PCCT) datasets. Material and Methods: Forty consecutive patients who underwent contrast-enhanced PCCT were retrospectively included and divided into training ( n = 20) and testing ( n = 20) cohorts. A supervised U-Net-based convolutional neural network was trained to generate VCE images from virtual non-contrast inputs, using true contrast-enhanced (TC) images as the reference. Quantitative similarity was assessed using the structural similarity index measure (SSIM), mean absolute error (MAE), mean squared error (MSE), and peak signal-to-noise ratio (PSNR). Qualitative evaluation was performed independently by two radiologists using a 5-point Likert scale across thoracic and abdominal structures, with assessment of exact, ±1-point, and diagnostic agreement. Results: Quantitative analysis demonstrated high similarity between VCE and TC images, with very high SSIM and PSNR values and low MAE, while MSE showed a right-skewed distribution. Qualitatively, VCE images were consistently rated lower than TC images. However, central thoracic vascular structures, cardiac chambers, and mediastinal lymph nodes were frequently rated as diagnostic (Likert ≥3) with high diagnostic agreement. In contrast, abdominal solid organs and vessels were often judged non-diagnostic, mainly due to heterogeneous enhancement and apparent contrast defects. Conclusion: The synthesis of VCE images from PCCT datasets is feasible and shows excellent quantitative similarity to TC images, with promising results for thoracic applications but limited reliability for abdominal evaluation at this stage.
Objectives: There is a lack of literature detailing evidence of osseous fusion following mandibular free flap reconstruction. This purpose of this study was to determine the presence of osseous union following mandibular free flap reconstruction, the timing of fusion and risk factors associated with non-union. Material and Methods: A retrospective chart and imaging review was performed to determine the presence of fusion and risk factors for non-union following fibular free flap reconstruction of the mandible. Indications for surgery included malignancy, benign lesions, osteoradionecrosis, and trauma. Chi-square analyses were performed in aggregate and for each subgroup to determine associations between different factors for the presence of fusion. Results: This study included 79 subjects with 62 (78%) achieving at least partial fusion, and 53 (67%) achieving complete fusion. Subjects who underwent surveillance imaging for longer periods of time were more likely to achieve fusion. ( p <0.005). Malignant lesions were more likely to fuse than other subgroups ( p <0.029). T4 lesions had less fusion ( p <0.048). Adjuvant chemotherapy ( p <0.035), steroids ( p <0.046), and prior radiotherapy ( p <0.024) were associated with transient delays in fusion. Conclusion: Most patients undergoing mandibular reconstruction demonstrate complete fusion at one year after surgery. Transient delays in bone union may occur secondary to adjuvant chemotherapy, perioperative steroid use and prior radiotherapy.
Lower extremity swelling has a broad differential diagnosis, including lymphedema, obesity-induced lymphedema, phlebolymphedema, and lipedema. Although these conditions may appear similar clinically, their pathophysiology and lymphoscintigraphic findings differ. Obesity, venous insufficiency, and abnormal adipose tissue can complicate image interpretation. We present four representative cases to illustrate characteristic imaging patterns across these conditions. These cases highlight the importance of interpreting lymphoscintigraphy in a clinical context.
Objectives:To evaluate the effect of COVID-19 on a mobile screening mammography program as measured by turnaround time (TAT) in days between an abnormal screening mammogram (sMG) and diagnostic mammography. Material and Methods:All of our institution's sMG (mobile and non-mobile) from January 2017, to December 2022 were retrospectively reviewed, and those dated March 7, 2020-July 7, 2020 were excluded because our mobile sMG program was non-operative at that time due to COVID-19. TATs and patient demographics were compared for mobile and non-mobile sMG patients between 2 time periods: Pre-pandemic (January 1, 2017-March 6, 2020) and pandemic (July 8, 2020-December 31, 2022). Statistics included multiple linear regression analysis, Fisher's Exact, and Wilcoxon Rank Sum tests. Results:During the pre-pandemic period, 11,439 female patients (9309 without insurance, 81.3%) underwent 14,161 mobile sMG, while 28,737 female patients (429 without insurance, 1.5%) underwent 57,840 non-mobile sMG. During the pandemic period, 6805 female patients (6720 without insurance, 98.8%) underwent 7663 mobile sMG, while 32,655 female patients (868 without insurance, 2.7%) underwent 53,540 non-mobile sMG. Median TATs for mobile uninsured patients increased from 41 days during the pre-pandemic period to 51 days during the pandemic period (p < 0.001), while median TATs for non-mobile insured patients decreased from 20 days during the pre-pandemic period to 14 days during the pandemic period (p < 0.001). Increased TATs were associated with Asian, African American, and Other race compared with White race (Asian, p = 0.004; African American, p < 0.001; and Other, p = 0.02) and self-pay insurance status (p = 0.006). Conclusion:For mobile uninsured screening patients, the number of days between screening and diagnostic mammography increased with the COVID-19 pandemic, while it decreased for non-mobile insured screening patients. Mobile uninsured mammography patients may represent a population that needs additional attention. These findings highlight a health equity concern, as the pandemic disproportionately widened disparities in timely follow-up care for uninsured patients served by mobile mammography programs.
Objectives:Single-shot echo-planar imaging sequences with parallel imaging are widely used for diffusion-weighted imaging (DWI). However, when small fields of view and higher phase-encoding reduction ratios (PRs) are applied, image quality may deteriorate because of imperfections in the unfolding process of parallel imaging. Previous studies have suggested that Zoomed DWI (Zoom-DWI) may address this limitation. Therefore, we compared Zoom-DWI with parallel DWI (Parallel-DWI) across different PRs to evaluate image quality. Material and Methods:Zoom-DWI and Parallel-DWI were performed using identical acquisition times and imaging parameters at different PRs. Signal-to-noise ratio (SNR), image uniformity, slice thickness, spatial resolution, and image distortion were evaluated. Results:At a PR of 66.6%, the SNR of Zoom-DWI was approximately 1.4-3.3-fold higher than that of Parallel-DWI at the image center, where reconstruction errors in parallel imaging become more pronounced as PR increases. Image uniformity was also higher in Zoom-DWI than in Parallel-DWI, and the difference increased by approximately 41.0% at a PR of 66.6%. Slice thickness, spatial resolution, and image distortion were comparable between the two methods. Conclusion:In this phantom study, Zoom-DWI demonstrated higher SNR and greater image uniformity than Parallel-DWI, particularly at higher PRs and in the central image region.
Objectives:Struma ovarii (SO) is an extremely rare clinical condition. This study retrospectively analyzes clinical and imaging data from 11 misdiagnosed cases of struma ovarii to identify key diagnostic and differential imaging features. Material and Methods:A retrospective analysis was performed on the clinical and imaging features of 11 patients with initially misdiagnosed but postoperatively confirmed ovarian struma, who were treated at our hospital. Imaging features analyzed included lesion size, computed tomography (CT) density, calcification status, magnetic resonance imaging (MRI) signal characteristics (cystic/solid components), enhancement intensity, and lymph node or distant metastasis. Clinical features analyzed comprised patient symptoms and laboratory test results. Results:All 11 unilateral ovarian lesions measured 10.77 ± 4.43 cm. MRI demonstrated markedly hypointense foci on T2-weighted images in the cyst wall septa in 90.9% of cases (10/11), isointense to mildly hyperintense signal on T1-weighted images in cystic cavities in 63.6% (7/11), and small to moderate volume ascites in 81.8% (9/11). On contrast-enhanced MRI, the solid components exhibited a honeycomb-like enhancement pattern: enhancement was comparable to the myometrium in 4 cases, greater in 4 cases, and slightly lower in 3 cases. One case demonstrated restricted diffusion on diffusion-weighted imaging along with multiple pelvic disseminated nodules. On non-contrast CT, all cases showed slightly high-density foci (66.56 ± 8.23 HU), with punctate or nodular calcifications in 54.5% (6/11). In the subset of three patients who underwent contrast-enhanced CT, marked enhancement of the solid components was observed in all cases. Conclusion:The radiological manifestations of SO demonstrate distinct characteristic features. When combined with clinical findings, these imaging features may assist in diagnosis and improve diagnostic accuracy.
Objectives: Neonatal imaging is particularly challenging because newborns are prone to head motion, which can degrade image quality and complicate interpretation. Improving brain magnetic resonance imaging (MRI) image quality may help reduce diagnostic uncertainty and facilitate the nuanced assessment of early myelinating structures in the neonatal brain. Although deep learning reconstruction algorithms designed to improve MRI image quality have been evaluated in pediatric imaging, they have not been specifically studied in exclusively neonatal populations. This pilot study sought to evaluate image quality improvement through the employment of a deep learning reconstruction algorithm in neonatal brain imaging. Materials and Methods: 3D T1-weighted brain MRIs were obtained in a small cohort of 15 neonates. A deep learning reconstruction algorithm was applied to the image sets using low, medium, and high levels of denoising. Three radiologists qualitatively rated image quality (signal-to-noise ratio [SNR], presence of artifacts, and overall clarity) on a 4-point scale of eight early myelinating structures. Objective apparent SNR (aSNR) and apparent contrast-to-noise ratio (aCNR), based on signal intensities of white and gray matter, were measured across all three denoising levels. Results: Evaluation by radiologists indicated an overall increase in all image quality categories and increased conspicuity of the early myelinating structures as the level of denoising increased. Objective aSNR and aCNR values also increased progressively with denoising, with significant differences observed for nearly all pairwise comparisons. Conclusion: Our findings suggest improvement in image quality with the use of the deep learning reconstruction algorithm in 3D T1-weighted neonatal brain MRI, though the small sample size and pilot design limit generalizability. Diagnostic accuracy and clinical outcomes were not evaluated and warrant future investigation.
Although uterine leiomyomas (fibroids) are benign and frequently seen in genitourinary imaging, their degeneration features may overlap with malignant entities. Accurate characterization of uterine fibroids (UFs) and its differentiation from other malignancies not only helps alleviate patients’ anxiety but also assists with treatment plans, either medical or surgical. This article aims to outline the main magnetic resonance imaging characteristics of each fibroid degenerating type with case-based illustrations. This will also outline essential imaging features to differentiate degenerating UFs from other malignant entities.
Objectives:The objective of the study is to assess the technical feasibility, safety, and clinical efficacy of balloon-occluded retrograde transvenous obliteration (BRTO) using low-cost, off-label balloon catheters. Material and Methods:A retrospective study was conducted on 31 patients (20 males, 11 females; mean age 56.6 years; range 47-75 years) who underwent BRTO between January 2009 and November 2023. All patients had gastric varices with a demonstrable gastrorenal shunt on pre-procedural computed tomography; six of them presented with intractable hepatic encephalopathy. Off-label balloon catheters (Swan-Ganz, Fogarty, or stone extractor) were selected based on shunt anatomy. Sodium tetradecyl sulfate foam, with or without Lipiodol, was used as the sclerosing agent. Technical success was defined as sustained sclerosant stasis during balloon inflation. Clinical success was defined as cessation of variceal bleeding or resolution of encephalopathy. Results:Technical success was achieved in 29 of 31 patients (93.5%). Balloon rupture or deflation occurred in two patients; however, hemostasis was successfully maintained without any rebleeding. Of the 25 patients with follow-up data (mean 953.6 days; range 1-4015 days), clinical success was observed in 23 (92%). One patient required surgical shunt creation for immediate post-procedure bleeding, and another experienced rebleeding after 1 year, which was successfully managed with a transjugular intrahepatic portosystemic shunt. Among 17 patients with follow-up imaging or endoscopy, complete obliteration of gastric varices was observed in 70.5% and partial obliteration in 29.5%. Balloon-related complications were rare and not associated with adverse clinical outcomes. Conclusion:BRTO using inexpensive off-label balloon catheters is a technically feasible, safe, and clinically effective treatment for gastric varices and hepatic encephalopathy. In combination with a modified Lipiodol-free sclerosant protocol, this technique offers a cost-effective alternative to conventional BRTO in resource-constrained environments. Prospective studies are needed to confirm these findings and to develop standardized clinical guidelines.
Objectives: Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer lacking estrogen receptor, progesterone receptor, and human epidermal growth factor R expression. This study aimed to identify ultrasound features associated with TNBC and construct a robust diagnostic model using machine learning techniques. Material and Methods: A total of 433 BC patients (47 TNBC and 386 non-TNBC) with complete clinical and ultrasound data were retrospectively analyzed. Univariate and multivariate logistic regression analyses identified independent ultrasound predictors of TNBC. Subsequently, 108 combinations of feature selection methods and machine learning classifiers were systematically evaluated to identify the optimal diagnostic model. Model performance was assessed using receiver operating characteristic curves, decision curve analysis (DCA), and calibration plots in both training and validation cohorts. The ethical approval was obtained from the institutional review board, and the requirement for individual written informed consent was waived due to the retrospective nature of the study. Results: Multivariate analysis identified posterior acho, margins, calcification, and aspect ratio as independent predictors of TNBC ( p < 0.05). Among all model combinations, the Stepwise Generalized Linear Model combined with Random Forest model achieved the best performance, with an area under the curve (AUC) of 1.000 in the training set and 0.913 in the validation set. Subgroup analysis revealed higher model accuracy in patients aged ≤50 years (AUC = 0.911) compared to those >50 years (AUC = 0.706). DCA and calibration plots indicated high clinical utility and excellent calibration performance. Conclusion: Specific ultrasound features can effectively distinguish TNBC from non-TNBC. A machine learning-based diagnostic model that integrates multiple algorithmic combinations demonstrates strong generalizability and may serve as a valuable clinical tool, particularly for younger patients.
Objectives: This study evaluates the diagnostic yield and utilization patterns of head and neck computed tomography angiography (CTAHN) in screening patients in the emergency department (ED) for blunt cerebrovascular injury. This study was conducted at a Level 1 trauma center serving a large geographical area with a high number of regional transfers. This study evaluates the prevalence of CTAHN overutilization in the ED and examines whether diagnostic yield correlates with adherence to the modified Denver criteria, transfer status, and trauma severity. Material and Methods: A retrospective chart review was conducted of patients presenting to the ED between January 01, 2021, and December 31, 2023. Patients over the age of 16 were included in this study if they presented with blunt traumatic injury and subsequently underwent CTAHN or neck CTA (CTAN) imaging during their ED evaluation. A multivariable regression analysis was performed to evaluate the association between CTA yield and factors including patient transfer status, trauma severity designation, and adherence to the modified Denver criteria. Results: A total of 643 patients met the inclusion criteria. A substantial proportion (74.2%) of CTAHN and CTAN examinations yielded negative results, with significant correlation to nonadherence to the modified Denver criteria. We found no significant association between CTAHN yield and transfer status or trauma level designation. Of the patients found to have trauma related actionable findings, 71.8% had adherence to the modified Denver criteria during triage screening. Conclusion: A high proportion of CTAHN and CTAN studies ordered from the ED yield low-value diagnostic results, with overutilization closely linked to nonadherence to the modified Denver criteria. Our findings carry important implications for quality improvement efforts, including unnecessary radiation exposure to patients and reduced efficiency in the ED. Enhanced guideline compliance may serve as a modifiable target to reduce diagnostic imaging overutilization.
Objectives: The objective of this study is to assess cases of septic arthritis of the glenohumeral joint and its association with intravenous drug use. Material and Methods: Retrospective data from the past 10 years were obtained from the University Hospital System in Appalachia. 53 shoulders in 50 patients fit the inclusion criteria for glenohumeral septic arthritis and are included in the study. Statistical analyses were carried out using statistical software R (version 3.6.3, R Foundation, Vienna, Austria). Comparisons were made between cases with intravenous drug use versus all other cases. Results: The mean age for intravenous drug users with glenohumeral septic arthritis is lower than non-users. Intravenous drug users with glenohumeral septic arthritis also had higher rates of sepsis, bacteremia, endocarditis, septic emboli, and involvement of other joints compared to non-users. Conclusion: A younger age, the involvement of other joints, and presence of other severe infections should prompt the radiologist to further probe into any intravenous drug use, which may not always be previously divulged. Conversely, having a known history of intravenous drug use should prompt the radiologist to be on the lookout for other joint infections, endocarditis, and septic emboli.
A 55-year-old female presented with a persistent headache in the left parietal region for more than 2 months. Non-contrast computed tomography demonstrated irregular cast-like soft tissue densities along the walls of both lateral ventricles, with a cystic-solid mass located in the anterior horn of the left lateral ventricle. Magnetic resonance imaging findings strongly suggested a subependymoma involving both lateral ventricles. The patient underwent tumor resection, and histopathology confirmed subependymoma (World Health Organization Grade I) with cystic degeneration and hemosiderin deposition. This case is a rare diffuse subependymoma of both lateral ventricles with cystic degeneration and old hemorrhage. The clinical and imaging features are reported as follows.
Small bowel bleeding is an uncommon cause of gastrointestinal hemorrhage and is often difficult to diagnose when upper and lower endoscopy fail to identify the bleeding source. Dynamic contrast-enhanced computed tomography (DCE-CT) has emerged as an important imaging modality for localizing lesions, estimating the underlying etiology, and guiding treatment strategies. We report two cases of small bowel bleeding with distinct etiologies: Arteriovenous malformation (AVM) and gastrointestinal stromal tumor (GIST). In the first case, DCE-CT demonstrated a mass-like lesion with intense arterial-phase enhancement comparable to adjacent arteries and early venous drainage, strongly suggesting a vascular lesion. Elective surgical resection was performed, and histopathological examination confirmed AVM. In the second case, CT revealed a well-defined mass with relatively persistent enhancement and contrast extravasation, indicating active bleeding from a neoplastic lesion. Due to hemodynamic deterioration, emergency surgical resection was required, and the lesion was diagnosed as GIST. These cases indicate that systematic evaluation of enhancement patterns and associated CT findings, including early venous drainage and contrast extravasation, can facilitate differentiation between vascular and neoplastic causes of small bowel bleeding and support appropriate treatment selection.
Uterine leiomyomas are common benign smooth muscle tumors typically confined to the uterus and hormonally responsive to estrogen and progesterone, typically regressing after menopause. Rarely, they demonstrate metastatic behavior despite benign histology, a condition known as benign metastasizing leiomyoma (BML). BML is exceedingly rare and can mimic malignancy, posing diagnostic challenges. We report a rare case of a 53-yearold woman with a history of hysterectomy for leiomyomas who presented with dyspnea and chest pain. Imaging revealed numerous bilateral pulmonary nodules, later confirmed to be smooth muscle tumors. After being lost to follow-up, she returned 2 years later with new breast and forearm masses. Imaging and biopsy confirmed metastatic smooth muscle tumors consistent with BML. Breast lesions mimicked benign cysts on ultrasound, underscoring the importance of clinical and histological correlation. The patient responded well to treatment with symptom improvement. This case highlights the rare phenomenon of BML metastasizing to multiple extrauterine sites, including the breast and soft tissues, locations infrequently reported. Imaging findings, particularly in the breast, can mimic benign lesions such as simple cysts, underscoring the need for biopsy and correlation with clinical history. BML should be considered in women with a history of uterine fibroids and indolent-appearing metastases without fludeoxyglucose uptake on positron emission tomography, computed tomography, and cystic appearance on ultrasound of breast lesions. Early recognition is crucial to avoid misclassification as malignancy and to guide effective hormonal treatment.
Adrenal masses are increasingly detected incidentally on imaging due to the widespread use of advanced imaging modalities and require a multidisciplinary approach for accurate diagnosis and management. This case report describes a patient who initially presented with lower extremity deep vein thrombosis and was found to have a right adrenal mass upon cross-sectional imaging. Atypical features noted on further imaging prompted investigation of the mass, with histopathologic analysis and PCR sequencing ultimately identifying Mycobacterium genavense infection as the cause. This case highlights the importance of maintaining a broad differential for incidental adrenal findings and the critical role of histopathology for definitive diagnosis.
The Ovarian-Adnexal Reporting and Data System (O-RADS) ultrasound and MRI lexicon guidelines have standardized preoperative assessment of adnexal masses and improved communication with clinicians. However, in premenopausal women who have undergone ovarian cystectomy, post-operative ovarian appearances may mimic indeterminate or suspicious lesions, posing interpreting challenges. This illustrative educational case series highlights characteristic post-operative imaging features following cystectomy for borderline ovarian tumors (BOTs), emphasizing some common pearls and pitfalls. The cases underscore that while O-RADS is validated for preoperative adnexal assessment, post-operative ovaries constitute a recognized gray zone where familiarity with these imaging nuances is crucial for accurate interpretation.
Objectives:Household air pollution from biomass fuel combustion remains a major global health burden, affecting nearly 3 billion people worldwide. Although biomass smoke exposure is a recognized risk factor for chronic airway disease, its role in interstitial lung disease (ILD) is less well defined, and characteristic CT features have not been systematically described in patients without coexisting chronic obstructive pulmonary disease (COPD). Material and Methods:We conducted a retrospective review of 23 patients with biomass smoke exposure and radiographic evidence of ILD, excluding those with alternative ILD etiologies or pre-existing COPD. CT scans were independently assessed by a thoracic radiologist and two pulmonologists for predominant patterns, distributions, and additional findings, with consensus classification. We report proportions with 95% confidence intervals (CIs) and performed exploratory Spearman correlation to assess associations between selected CT features. Results:The cohort (mean age 71.7 years; all females; 96% born outside the United States) most commonly demonstrated reticulation (16/23, 70%; 95% CI, 49-84%), ground-glass opacities (GGO) (15/23, 65%; 95% CI, 45-81%), mosaic attenuation (15/23, 65%; 95% CI, 45-81%), and bronchial wall thickening (14/23, 61%; 95% CI, 41-78%). Abnormalities were typically patchy (18/23, 78%; 95% CI, 58-90%) and peribronchial (13/23, 57%; 95% CI, 37-74%), without consistent apical or basal predominance. Traction bronchiectasis occurred in 12/23 (52%; 95% CI, 33-71%) and lymphadenopathy in 9/23 (39%; 95% CI, 22-59%). Honeycombing (5/23, 22%; 95% CI, 10-42%), centrilobular emphysema (4/23, 17%; 95% CI, 7-37%), nodules (3/23, 13%; 95% CI, 5-32%), cysts (2/23, 9%; 95% CI, 2-27%), tree-in-bud opacities (2/23, 9%; 95% CI, 2-27%), and centrilobular nodularity (1/23, 4%; 95% CI, 1-21%) were uncommon. Exploratory Spearman analyses showed strong associations between mosaic attenuation and bronchial wall thickening (ρ = 0.91) and between peribronchial distribution and mosaic attenuation (ρ = 0.83), with additional positive correlations between mosaic attenuation and bronchiectasis (ρ = 0.70), peribronchial distribution and bronchial wall thickening (ρ = 0.73), bronchial wall thickening and bronchiectasis (ρ = 0.77), bronchiectasis and traction bronchiectasis (ρ = 0.57), and reticulation and traction bronchiectasis (ρ = 0.69). Exploratory Spearman correlation analyses showed strong associations between mosaic attenuation and bronchial wall thickening (ρ = 0.91) and between peribronchial distribution and mosaic attenuation (ρ = 0.83), with additional positive correlations between mosaic attenuation and bronchiectasis (ρ = 0.70), peribronchial distribution and bronchial wall thickening (ρ = 0.73), bronchial wall thickening and bronchiectasis (ρ = 0.77), bronchiectasis and traction bronchiectasis (ρ = 0.57), and reticulation and traction bronchiectasis (ρ = 0.69). Conclusion:Biomass smoke-associated ILD demonstrates a distinctive CT pattern characterized by reticulation, GGOs, and mosaic attenuation with patchy and peribronchial distribution and no clear zonal predominance. Unlike hypersensitivity pneumonitis, it lacks centrilobular nodularity. Compared with idiopathic pulmonary fibrosis (IPF), it shows less extensive subpleural honeycombing, more peribronchial involvement, and no consistent basal predominance. These distinctions may improve recognition of biomass smoke-associated ILD in exposed patients. Further prospective studies are needed to validate these findings and clarify their prognostic significance.
Objectives: The objective of the study is to investigate the diagnostic value of apparent diffusion coefficient (ADC) parameters in differentiating prostate cancer (PCa) pathology grading groups (GG) and their correlation with Ki-67 proliferation index. Material and Methods: This single-center retrospective study analyzed magnetic resonance imaging data from 119 pathologically confirmed PCa cases with documented Ki-67 proliferation indices. Both mean ADC (ADC(mean)) and minimum ADC (ADC(min)) values were obtained from dominant lesions using ADC mapping. Comparative analysis was performed between high-risk PCa (hPCa) and non-high-risk PCa (nhPCa) groups. Diagnostic performance was assessed through receiver operating characteristic (ROC) curve analysis, while Spearman correlation was employed to evaluate relationships between ADC parameters, GG, and Ki-67 index. Results: Significantly lower ADC(mean )and ADC(min )values were observed in hPCa compared to nhPCa (P < 0.001). ROC analysis demonstrated the diagnostic utility of ADC parameters in distinguishing hPCa from nhPCa. Both ADC(mean )and ADC(min )showed significant negative correlations with GG and Ki-67 proliferation index (P < 0.001). Conclusions: This study demonstrates an inverse correlation between ADC values and tumor proliferative activity in PCa, providing biological validation for DWI in assessing tumor aggressiveness. While this quantitative parameter shows potential for risk stratification, its application requires further multicenter validation.
Objectives:This study aims to compare the effects of deep learning image reconstruction (DLIR) and adaptive statistical iterative reconstruction-veo (ASIR-V) algorithms on the image quality of cranial computed tomography angiography (CTA) reconstructed from computed tomography perfusion (CTP) data and to evaluate their agreement with digital subtraction angiography (DSA), the gold standard for diagnosing arterial stenosis. Material and Methods:This retrospective study enrolled patients with clinically suspected cerebrovascular disease who had undergone CTP examination. From the arterial peak phase of CTP raw data, four CTA datasets were reconstructed: ASIR-V 40%, ASIR-V 80%, DLIR low setting (DLIR-L), and DLIR high setting (DLIR-H). Regions of interest were placed at the M1 segment of the middle cerebral artery (MCA), basilar artery (BA), and internal carotid artery (ICA) on the healthy side and the temporalis muscle. Computed tomography attenuation values and standard deviations were measured, and the contrast-to-noise ratio(CNR) and signal-to-noise ratio (SNR) were subsequently calculated using the attenuation values and standard deviations. Vessel edge sharpness was objectively assessed using edge rise distance (ERD) and edge rise slope (ERS). Using DSA as the reference standard, diagnostic performance for vascular stenosis was evaluated, and agreement was analyzed with the Kappa test. Two radiologists independently scored subjective image quality using a 5-point Likert scale. Results:Sixty-five patients were included, 14 of whom additionally underwent DSA. For the MCA, ICA, and BA, image noise in the DLIR-H group was significantly lower than that in the other groups, with statistically significant differences compared with ASIR-V 40% (p < 0.05). For CNR and SNR, DLIR-H and ASIR-V 80% outperformed ASIR-V 40% and DLIR-L across all arterial levels (p < 0.05). ERD and ERS were significantly superior in the DLIR groups compared with the ASIR-V groups (p < 0.05). In subjective evaluations, the DLIR-H group achieved the highest scores across all parameters (p < 0.05). Agreement with DSA was excellent for DLIR-H (κ = 0.819), significantly higher than for ASIR-V (p < 0.05). Conclusion:In CTP examinations for suspected cerebrovascular disease, DLIR-H markedly improves cranial CTA image quality compared with ASIR-V, while achieving higher diagnostic agreement with DSA. DLIR-H can be recommended as the preferred clinical reconstruction method.
