Application value of adrenal venous sampling in the surgical treatment of primary aldosteronism.

The diagnosis of primary aldosteronism (PA) is critical for determining treatment strategies. The aim of the present study was to investigate the clinical value of preoperative adrenal venous sampling (AVS) for determining the benefit of PA surgery. Patients diagnosed with PA at Liaocheng People's Hospital (Liaocheng, China) between January 2015 and December 2020 were selected and divided into two groups: Group A underwent adrenal computed tomography (CT) only, whereas Group B underwent adrenal CT and successful AVS. Subsequently, the improvement rate of adrenal CT and adrenal CT + AVS in the treatment of PA was compared. A total of 164 patients were included, with an average age of 46.69±13.64 years. There were 62 patients in Group A and 102 in Group B. Among the patients diagnosed with unilateral lesions on adrenal CT scan, 82.61% of patients in group A and 87.72% in group B showed improvement; however, the difference was not significant (χ2=0.534, P=0.465). Among the patients diagnosed with bilateral lesions on adrenal CT images, 62.50% of patients in Group A and 91.11% of patients in Group B showed improvement (P=0.019). In conclusion, unilateral adrenal lesions detected by CT did not benefit significantly from surgical decision-making after AVS. AVS should be advised for all patients with bilateral adrenal PA who are willing to undergo adrenal surgery, which is conducive to correct lateral segmentation and improve treatment choices.

Seizures as the only presentation of Pulmonary Embolism in the absence of Respiratory Symptoms.

Pulmonary embolism is a life-threatening emergency. Seizure as the clinical presentation of pulmonary embolism is extremely rare. In this case report a 47-year-old female had an episode of seizure after undergoing total abdominal hysterectomy with bilateral salpingo-oophorectomy due to myometrial uterine fibroids. The patient had no past history of seizure or cardiovascular disease. Based on raised D-Dimers and echocardiography a provisional diagnosis of pulmonary embolism was made, which was confirmed on CT angiogram that showed bilateral saddle pulmonary embolism. Clinicians need to be aware that Pulmonary embolism is a possibility as the differential diagnosis for unexplained, new-onset of seizure activity.

The Role of CT Perfusion in Differentiating Benign Versus Malignant Focal Pulmonary Lesions.

BACKGROUND: Contrast-enhanced CT scan is the standard imaging for the characterization and evaluation of focal parenchymal lung lesions. It relies on morphology and enhancement patterns for the characterization of lung lesions. However, there is significant overlap among imaging features of various malignant and benign lesions. Hence, it is often necessary to obtain tissue diagnosis with invasive percutaneous or endoscopic-guided tissue sampling. It is often desirable to have non-invasive techniques that can differentiate malignant and benign lung lesions. CT perfusion is an emerging CT technology that allows functional assessment of tissue vascularity through various parameters and can help in differentiating benign and malignant focal lung lesions. OBJECTIVE: The purpose of this study was to assess the role of the CT perfusion technique in differentiating malignant and benign focal parenchymal lung lesions. MATERIALS AND METHODS: In this prospective observational study, CT perfusion was performed on 41 patients with focal parenchymal lung lesions from December 2020 to June 2022. The four-dimensional range was planned to cover the entire craniocaudal extent of the lesion, followed by a volume perfusion CT (VPCT) of the lesion. A total of 27 dynamic datasets were acquired with a scan interval of 1.5 seconds and a total scan time of 42 seconds. CT perfusion parameters of blood flow (BF), blood volume (BV), and k-trans of the lesion were measured with mathematical algorithms available in the Syngo.via CT perfusion software (Siemens Healthcare, Erlangen, Germany). RESULTS: The median BV in benign lesions was found to be 5.5 mL/100 g, with an interquartile range of 3.3-6.9 and a p-value < 0.001. The median BV in malignant lesions was found to be 11.35 mL/100 g, with an interquartile range of 9.57-13.21 and a p-value ≤ 0.001. The median BF for benign lesions was 45.5 mL/100 g/min, with an interquartile range of 33.8-48.5 and a p-value ≤ 0.001. The median BF for malignant lesion was 61.77 mL/100 g/min, with an interquartile range of 33.8-48.5 and a p-value ≤ 0.001. The median k-trans in the case of benign lesions was found to be 4.2 mL/100 g/min, with an interquartile range of 3.13-6.8 and a p-value ≤ 0.001. The median k-trans in the case of the malignant lesion was found to be 12.05 mL/100g/min, with an interquartile range of 7.20-33.42 and a p-value < 0.001. Our study has also shown BV to have an accuracy of 92.68%, sensitivity of 93.3%, and specificity of 90.01%. CONCLUSION: Our study has shown that CT perfusion values of BV, BF, and k-trans can be used to differentiate between benign and malignant focal lung parenchymal lesions. K-trans is the most sensitive parameter while BV and BF have greater accuracy and specificity.

Challenges and Successes in Introducing Coronary CT Angiography in an Emergency Medicine-Run Observation Unit.

This study was designed to analyze the departmental changes in transitioning the Emergency Department (ED)-run Observation Medicine Unit's routine noninvasive cardiac evaluation from the traditional standard-of-care procedures to coronary computed tomography angiography (CCTA).  While the routine use of CCTA for the evaluation of chest pain has been deemed feasible and safe, provider confidence appears apprehensive, and ordering patterns appear reluctant to change.  We conducted a retrospective analysis of data from two risk-matched cohorts of ED patients who presented with symptoms suggestive of acute coronary syndrome (ACS) but without ischemic electrocardiogram (ECG) changes or positive troponin. Endpoints included length of stay, major adverse cardiovascular event (MACE) rates at 28 days, recidivism rate, and downstream findings on coronary catheterization.  The adoption of CCTA led to a significant reduction in the length of stay for patients in the ED-run Observation Medicine Unit. Provider and nursing education initiatives were crucial in overcoming initial resistance and improving the implementation of CCTA. Post-education, there was a marked increase in the volume of CCTA performed and a decrease in the length of stay, enhancing overall departmental throughput.  The results suggest that CCTA offers a reliable and efficient diagnostic alternative to traditional noninvasive tests, with high diagnostic accuracy contributing to faster decision-making and reduced need for invasive procedures. Continuous education for providers and nursing staff was essential to ensure adherence to the new protocol and improve clinical outcomes.  Transitioning to CCTA for routine noninvasive cardiac evaluation in the ED-run Observation Medicine Unit demonstrated significant efficiency and diagnostic accuracy benefits. Successful implementation requires targeted educational efforts to ensure competency and confidence among healthcare providers. The findings support the integration of CCTA into standard clinical practice for the evaluation of chest pain in the emergency setting, with future research needed to validate these results in broader patient populations and assess long-term outcomes.

Enhanced CT-Based Intratumoral and Peritumoral Radiomics Nomograms Predict High-Grade Patterns of Invasive Lung Adenocarcinoma.

RATIONALE AND OBJECTIVES: Extraction of intratumoral and peritumoral radiomics features combined with clinical factors to establish nomograms to predict high-grade patterns (micropapillary and solid) of invasive adenocarcinoma of the lung (IAC). MATERIALS AND METHODS: A retrospective study was conducted on 463 patients with pathologically confirmed IAC. Patients were randomized in a 7:3 ratio into a training cohort (n = 324) and a testing cohort (n = 139). A total of 2154 CT-based radiomic features were extracted from each of the four regions: gross tumor volume (GTV) and gross peritumoral tumor volume (GPTV3, GPTV6, GPTV9) containing peri-tumor regions of 3 mm, 6 mm, and 9 mm. A radiomics nomogram was constructed based on the optimal radiomics model and clinically independent predictors. RESULTS: The GPTV3 radiomics model showed better predictive performance in the testing group compared to the GTV (0.840), GPTV6 (0.843), and GPTV9 (0.734) models, with an AUC value of 0.889 in the testing group. In the clinical model, tumor density and the presence of a spiculation sign were identified as independent predictors. The nomogram, which combined these independent predictors with the GPTV3-Radscore, proved to be clinically useful. CONCLUSION: The GPTV3 radiomics model was superior to the GTV, GPTV6, and GPTV9 radiomics models in predicting high-grade patterns (HGP) of IAC. In addition, nomograms based on GPTV3 radiomics features and clinically independent predictors can further improve the prediction efficiency.

Effect of Matrix Size and Acquisition Mode on Image Quality and Radiation Dose of Ultra-High-Resolution CT of the Temporal Bone: An Anatomical Study.

Purpose: To compare image quality and radiation exposure between super- and ultra-high-resolution helical and super-high-resolution volumetric CT of the temporal bone. Methods: Six cadaveric temporal bone specimens were used to evaluate key temporal bone structures using the following CT reconstruction and acquisition modes: helical and single-volume acquisition modes in super-high resolution (0.25-mm slice thickness, 10242 matrix), and helical mode in ultra-high resolution (0.25-mm slice thickness, 20482 matrix). Two observers performed 5 previously described preoperative measurements, measured noise and signal-to-noise ratios for air, and noise for bone, and rated the visualization of 5 anatomical structures on a 4-point scale, for each reconstruction mode. Radiation dose exposure was recorded for each examination. Results: There was no significant difference between any of the quantitative or qualitative measurements in any of the reconstruction and acquisition modes. There was a slight increase in noise and a decrease in signal-to-noise ratio in the air using the single-volume mode (115 ± 13.1 HU and 8.37 ± 0.91, respectively) compared to the helicoidal super-high-resolution (92.4 ± 11.8 HU and 10.8 ± 1.26, respectively) and helicoidal ultra-high-resolution (91.1 ± 10.7 HU and 10.9 ± 1.39, respectively) modes (P < .002). The volumic CT dose index was 50.9 mGy with helical acquisition and 29.8 mGy with single-volume acquisition mode (P < .0001). Conclusion: The single-volume super-high-resolution acquisition mode allows a reduction in radiation dose exposure without compromising image quality compared to helical scanning, but with a slightly lower signal-to-noise ratio in air with the single-volume mode, while there was no difference in image quality between the helical super- and ultra-high-resolution modes.

The treatment effect across ASPECTS in acute ischemic stroke: Analysis from the AcT Trial.

BACKGROUND: Early ischemic changes on baseline imaging are commonly evaluated for acute stroke decision-making and prognostication. AIMS: We assess the association of early ischemic changes on clinical outcomes and whether it differs between intravenous tenecteplase versus Alteplase. METHODS: Data are from the phase 3, Alteplase compared to Tenecteplase (AcT) trial. Subjects with anterior circulation stroke were included. Early ischemic changes were assessed using the Alberta Stroke Program Early CT score (ASPECTS). Efficacy outcomes included modified Rankin scale (mRS) 0-1, mRS 0-2, and ordinal mRS at 90 days. Safety outcomes included 24-hour symptomatic intracerebral hemorrhage (sICH), any hemorrhage on follow-up scan, and 90-day mortality rate. Mixed effects logistic regression was used to assess the association of ASPECTS [continuous and categorical (0-4 vs. 5-7 vs. 8-10)] with outcomes and if these associations were modified by thrombolytic type after adjusting for age, sex, and baseline stroke severity. RESULTS: Of the 1577 patients in the trial, 901 patients (56.3%) (median age 75 years [IQR 65-84], 50.8% females, median NIHSS 14 [IQR 17-19]) with anterior circulation stroke were included. mRS 0-1 at 90d was achieved in 1/14 (0.3%), 43/160 (14.7%) and 252/726 (85.1%) in the ASPECTS 0-4, 5-7 and 8-10 groups respectively. Every 1-point decrease in ASPECTS was associated with 2.7% and 1.9% decrease in chances of mRS 0-1 and mRS 0-2 at 90 days, respectively, and 1.9% chances of increase in mortality at 90 days. Subgroup analysis in EVT treated population showed similar results. Thrombolytic type did not modify this association between ASPECTS and 90-day mRS 0-1 (P interaction 0.75). There was no significant interaction by thrombolytic type with any other outcome. CONCLUSIONS: Similar to prior studies, we found that every one-point decrease in ASPECTS was associated with poorer clinical and safety outcomes. This effect did not differ between alteplase and tenecteplase.

Evaluation of the pit and fissure system in primary and permanent molars with micro-computed tomography and 3D printing.

This study aimed to characterize the anatomical and physiological features of pits and fissures in primary and permanent molars by microtomographic (micro-CT) examination and three-dimensional (3D) printing. The occlusal surfaces of 84 primary molars and 60 permanent third molars were examined. The samples were scanned with micro-CT and the occlusal surface separated. The areas of the crown, its occlusal part, and fissures and pits were calculated. Digital impression of the occlusal surface was created and 3D printed. The frequency of different fissure types was determined by direct observation. Data were subjected to statistical analysis using Mann-Whitney U Test and chi-square test (p < 0.05). There was statistically significant difference between the ratio of occlusal surface and the crown area for the molars in primary and permanent dentitions (24.78% and 28.85% respectively, p < 0.05). In terms of the percentage ratio of the fissure area to the occlusal surface (24.24% and 22.30%) and the fissure area to the crown (6.02% and 6.52%), no significant difference was observed (p > 0.05). V-shaped fissures were predominant in both primary and permanent teeth, with a higher occurrence in primary dentition (59.48%, p < 0.05). Permanent molars exhibited a higher prevalence of I-type and U-type fissure configurations compared to primary molars (p < 0.05), with I-type fissures being the least common in primary molars. In both dentitions there was no statistically significant difference in the prevalence of IK-configuration (p > 0.05). The fissure depth was significantly greater in permanent molars than primary molars (p < 0.05). In conclusion, this study revealed remarkable diversity in fissure morphology among primary and permanent molars.

Mapping wrist motion: 3D CT analysis after scapholunate ligament transection.

The injury of the scapholunate (SL) ligament is common in wrist traumas leading to pain and reduced wrist function. The wrist's unique joint design and possible underlying theories as the carpal row theory were subject to earlier investigations studying wrist kinematics. Nevertheless, a comprehensive understanding of how SL ligament injuries affect wrist biomechanics is still lacking. Through a quantitative analysis of carpal bone motion patterns, we evaluated the impact on wrist kinematics occurring after SL ligament injury. We conducted a study using computer tomography imaging to analyse wrist kinematics after SL ligament transection in 21 fresh-frozen anatomical specimens. The collected data were then transformed into 3D models, employing both standardized global and object coordinate systems. The study encompassed the evaluation of rotation and translation for each individual carpal bone, as well as the ulna, and all metacarpal bones in reference to the radius. The study showed a significant increase in rotation towards palmar (p < 0.01), particularly notable for the scaphoid, following transection of the SL ligament during palmar flexion. Ulnar deviation did not significantly affect rotation or translation, and radial deviation also showed no significant changes in rotation or translation. The study highlights the significance of the SL ligament in wrist kinematics, revealing that SL ligament tears lead to changes in wrist motion. While we observed significant rotational changes for the scaphoid, other carpal bones showed less pronounced alterations, emphasizing the complexity of wrist biomechanics.

Relationship between stone volume, average CT value and operation time and efficiency before ureteral soft lens laser lithotripsy.

BACKGROUND: Soft ureteroscopic holmium laser lithotripsy is becoming increasingly popular as the preferred method for treating mid-to-lower ureteral stones. Studies have indicated that the size, composition, hardness, and fragility of the stones can impact the treatment's effectiveness. OBJECTIVE: To explore the relationship between stone volume, average CT value and operation time and efficiency before ureteral soft lens laser lithotripsy. METHODS: Our study on 126 patients undergoing ureteroscopic holmium laser lithotripsy for ureteral calculi from May 2020 to January 2022 categorized them into groups based on stone volume and CT value. We compared surgical outcomes and analyzed correlations between stone characteristics, operation parameters, and stone clearance rate to identify independent risk factors influencing treatment efficacy. RESULTS: Group A demonstrated significantly shorter operation durations and lower blood loss compared to Group B, along with higher single stone clearance rates and fewer postoperative complications. Similarly, Group C exhibited shorter operation times, reduced blood loss, higher stone clearance rates, and lower complication rates than Group D. Preoperative stone volume and CT value correlated positively with operation time and stone clearance rate, with both factors identified as independent risk factors affecting ureteral stone clearance following holmium laser lithotripsy. CONCLUSION: The stone volume and average CT value before ureteral soft lens laser lithotripsy show a positive correlation with operation time and efficiency, indicating that larger stone volumes and higher CT values lead to slower lithotripsy speeds and reduced operation efficiency. Furthermore, preoperative stone volume and average CT value are identified as independent risk factors for residual stones.

Clinical Performance Comparison of a Long Versus a Short Axial Field-of-View PET/CT Using EARL-Compliant Reconstructions.

PURPOSE: To ensure comparable PET/CT image quality between or within centres, clinical inter-system performance comparisons following European Association of Nuclear Medicine Research Ltd. (EARL) guidelines is required. In this work the performance of the long axial field-of-view Biograph Vision Quadra is compared to its predecessor, the short axial field-of-view Biograph Vision. PROCEDURES: To this aim, patients with suspected tumour lesions received a single weight-based (3 MBq/kg) 2-deoxy-2-[18F]fluoro-D-glucose injection and underwent routine clinical ( ∼ 15 min) scans on the Vision and 3-min scans on the Quadra in listmode in balanced order. Image quality (IQ), image noise (IN), and tumour demarcation (TD) were assessed visually by four nuclear medicine physicians using a 5-point Likert scale and semiquantitative analysis was performed using standardised uptake values (SUVs). Inter-reader agreement was tested using Wilcoxon's signed rank test and the SUVs were statistically compared using a paired t-test. RESULTS: Twenty patients (mean age, 60 years ± 8.8 [standard deviation], 16 male) were enrolled. Inter-reader agreement ranged from good to very good for IQ and IN (0.62 ≤ W ≤ 0.81), and fair for TD (0.29 ≤ W ≤ 0.39). Furthermore, a significant difference was found for TD (p = 0.015) between the systems, showing improved TD for the Quadra. CONCLUSION: This study demonstrates that the Quadra can be used in routine clinical practice with multiple PET/CT systems or in multicentre studies. This system provides comparable diagnostic image quality and semiquantitative accuracy, improved TD, and has the advantage of shorter scan durations.

Comparative Evaluation of Supplementary Cleaning Techniques for Removal of Bio-C Sealer and AH-Plus from Oval Root Canals: A Micro-CT Analysis.

Introduction: This study aimed to compare the effectiveness of two endodontic cleaning techniques, passive ultrasonic irrigation (PUI) and the XP-endo Finisher R (XPR) system, in removing residual filling material during endodontic retreatment procedures. Materials and Methods: Forty mandibular premolars with oval canals were divided into four groups based on the sealer used (AH-Plus or Bio-C Sealer) and the cleaning technique employed (PUI or XPR). To ensure uniformity of canal volume among groups, initial micro-CT scans were conducted. The canals were instrumented, filled, and then re-instrumented before undergoing either PUI or XPR cleaning techniques. Residual filling material volumes were assessed through micro-CT scans, and statistical analysis was performed using the Kruskal-Wallis and Mann-Whitney U tests. Results: Following instrumentation, there was no significant difference in residual filling material volumes between AH-Plus and Bio-C Sealer groups (1.35 mm3and 1.02 mm3, respectively; P>0.05). However, after supplementary cleaning techniques, XPR-cleaned specimens exhibited significantly less residual material compared to PUI-cleaned specimens (0.01 mm3 and 0.29 mm3 for Bio-C Sealer, and 0.07 mm3 and. 0.30 mm3 for AH-Plus, P<0.05). Conclusion: The XPR system was found to be more effective than PUI in removing residual filling material from Bio-C Sealer-filled root canals. This highlights its potential as a useful supplementary cleaning technique in endodontic retreatment procedures.

CBCT-based synthetic CT image generation using a diffusion model for CBCT-guided lung radiotherapy.

BACKGROUND: Although cone beam computed tomography (CBCT) has lower resolution compared to planning CTs (pCT), its lower dose, higher high-contrast resolution, and shorter scanning time support its widespread use in clinical applications, especially in ensuring accurate patient positioning during the image-guided radiation therapy (IGRT) process. PURPOSE: While CBCT is critical to IGRT, CBCT image quality can be compromised by severe stripe and scattering artifacts. Tumor movement secondary to respiratory motion also decreases CBCT resolution. In order to improve the image quality of CBCT, we propose a Lung Diffusion Model (L-DM) framework. METHODS: Our proposed algorithm is based on a conditional diffusion model trained on pCT and deformed CBCT (dCBCT) image pairs to synthesize lung CT images from dCBCT images and benefit CBCT-based radiotherapy. dCBCT images were used as the constraint for the L-DM. The image quality and Hounsfield unit (HU) values of the synthetic CTs (sCT) images generated by the proposed L-DM were compared to three selected mainstream generation models. RESULTS: We verified our model in both an institutional lung cancer dataset and a selected public dataset. Our L-DM showed significant improvement in the four metrics of mean absolute error (MAE), peak signal-to-noise ratio (PSNR), normalized cross-correlation (NCC), and structural similarity index measure (SSIM). In our institutional dataset, our proposed L-DM decreased the MAE from 101.47 to 37.87 HU and increased the PSNR from 24.97 to 29.89 dB, the NCC from 0.81 to 0.97, and the SSIM from 0.80 to 0.93. In the public dataset, our proposed L-DM decreased the MAE from 173.65 to 58.95 HU, while increasing the PSNR, NCC, and SSIM from 13.07 to 24.05 dB, 0.68 to 0.94, and 0.41 to 0.88, respectively. CONCLUSIONS: The proposed L-DM significantly improved sCT image quality compared to the pre-correction CBCT and three mainstream generative models. Our model can benefit CBCT-based IGRT and other potential clinical applications as it increases the HU accuracy and decreases the artifacts from input CBCT images.

In vitro and in vivo optimized reconstruction for low-keV virtual monoenergetic photon-counting detector CT angiography of lower legs.

BACKGROUND: Lower extremity peripheral artery disease frequently presents with calcifications which reduces the accuracy of computed tomography (CT) angiography, especially below-the-knee. Photon-counting detector (PCD)-CT offers improved spatial resolution and less calcium blooming. We aimed to identify the optimal reconstruction parameters for PCD-CT angiography of the lower legs. METHODS: Tubes with different diameters (1-5 mm) were filled with different iodine concentrations and scanned in a water container. Images were reconstructed with 0.4 mm isotropic resolution using a quantitative kernel at all available sharpness levels (Qr36 to Qr76) and using different levels of quantum iterative reconstruction (QIR-2-4). Noise and image sharpness were determined for all reconstructions. Additionally, CT angiograms of 20 patients, reconstructed with a medium (Qr44), sharp (Qr60), and ultrasharp (Qr72) kernel at QIR-2-4, were evaluated by three readers assessing noise, delineation of plaques and vessel walls, and overall quality. RESULTS: In the phantom study, increased kernel sharpness led to higher image noise (e.g., 16, 38, 77 HU for Qr44, Qr60, Qr72, and QIR-3). Image sharpness increased with increasing kernel sharpness, reaching a plateau at the medium-high level 60. Higher QIR levels decreased image noise (e.g., 51, 38, 25 HU at QIR-2-4 and Qr60) without reducing vessel sharpness. The qualitative in vivo results confirmed these findings: the sharp kernel (Qr60) with the highest QIR yielded the best overall quality. CONCLUSION: The combination of a sharpness level optimized reconstruction kernel (Qr60) and the highest QIR level yield the best image quality for PCD-CT angiography of the lower legs when reconstructed at 0.4-mm resolution. RELEVANCE STATEMENT: Using high-resolution PCD-CT angiography with optimized reconstruction parameters might improve diagnostic accuracy and confidence in peripheral artery disease of the lower legs. KEY POINTS: Effective exploitation of the potential of PCD-CT angiography requires optimized reconstruction parameters. Too soft or too sharp reconstruction kernels reduce image quality. The highest level of quantum iterative reconstruction provides the best image quality.

Dosimetric implications of kidney anatomical volume changes in 177Lu-DOTATATE therapy.

INTRODUCTION: This study aims to evaluate the use of CT-based whole kidney parenchyma (WKP) segmentation in 177Lu-DOTATATE dosimetry. Specifically, it investigates whether WKP volumes change during treatment and evaluates the accuracy of applying a single delineated WKP volume for dosimetry. Furthermore, it aims to determine the cause of WKP volume changes-whether caused by radiation or amino acid infusion-by comparing them with spleen volume changes as a marker for radiation-induced alterations. METHODS: SPECT/CT images of 18 patients were acquired over the abdomen approximately 4 h (h) (D0), 24 h (D1), 48 h (D2) and 168 h (D7) post-administration of 177Lu-DOTATATE. CT guided WKP volumes were measured before (baseline) and during treatment. Kidney activity concentrations at each time point were derived from CT-segmented WKP overlaid on SPECT scans. The accuracy of using WKP segmentation from a single CT for all time points was assessed against the gold standard of segmenting each WKP individually. Time-integrated activity calculations were based on a tri-exponential curve fit of the kidney activity concentration over time. Kidney absorbed doses were estimated under the assumption of local energy deposition. Additionally, the impact of various partial volume correction methods on dosimetry was evaluated. RESULTS: Whole-kidney parenchyma (WKP) volumes, ranging from 31 to 243 mL, showed a gradual increase from baseline (mean ± SD = 130.6 ± 46.1 mL) at the initial time points D0 (138.5 ± 44.7 mL) and D1 (139.4 ± 41.6 mL), followed by a slight decrease at D2 (132.8 ± 44.5 mL) and a further decrease at D7 (129.2 ± 42.7 mL). The volume increase at D0 and D1 was statistically significant. Spleen volume did not change during treatment, suggesting that amino acid infusion rather than irradiation effects caused WKP volume changes. Bland-Altman analysis revealed WKP volume biases of 8.77% (D0 vs. BL), 10.77% (D1 vs. BL), 1.10% (D2 vs. BL), and 1.10% (D7 vs. BL), with corresponding uncertainties of 24.4%, 23.6%, 25.4%, and 25.4%, respectively. When WKP segmentation from a single CT is applied across all SPECTs, these WKP volume changes could overestimate the activity concentration and mean absorbed doses up to 4.3% and 2.5%, respectively. The absorbed dose uncertainties using a recovery coefficient (RC) of 0.85 for single-time-point WKP delineation increase the absorbed dose uncertainty by 4% compared to the use of patient-specific RCs and time specific segmentation of WKP volumes. CONCLUSIONS: Kidney volume exhibited significant variation form D0 to D7, affecting the precision of dosimetry calculation, primarily due to errors in whole-kidney parenchyma (WKP) delineation. Notably, using WKP segmentation from a single CT scan applied to sequential SPECT images introduce further uncertainty and may lead to an overestimation of the absorbed dose. The fluctuations in kidney volume are most likely attributable to amino acid infusion.

Localization and etiological stratification of non-neoplastic small bowel bleeding via CT imaging: a 10-year study.

OBJECTIVES: The purpose of this study is to assess the diagnostic efficacy of contrast-enhanced CT scans for small bowel bleeding. METHODS: This retrospective study evaluated patients diagnosed with non-neoplastic small intestinal bleeding (including duodenum) who underwent abdominal CT at our institution from December 2013 to March 2023. Patients were categorized into diverticulum and non-diverticulum groups based on the cause of bleeding. Active bleeding was defined on the CT images as extravasation of contrast material in the intestinal lumen during the arterial phase and/or progressive accumulation of contrast material during the venous phase. We have documented the original report (extracted from the medical record system and additional consultation opinions from senior radiologists), including the presence of active bleeding and its potential bleeding location. Furthermore, two radiologists reassessed the CT images, seeking consensus on the diagnosis between them. RESULTS: The study included 165 patients, predominantly male, with a median age of 30 years. Active bleeding was identified in 48.3% of patients. Notably, all identified bleeding diverticula in the diverticulum group exhibited cul-de-sac termination. Among the identified causes of bleeding, Crohn's disease was most prevalent (46.7%, N of causes = 64). Significant differences were observed in the diagnostic methods between the diverticulum and non-diverticulum groups, with surgery predominantly applied in the diverticulum group, and endoscopy in the non-diverticulum group (n = 49 vs n = 15, p = 0.001). Contrast agent extravasation was significantly higher in the diverticulum group (n = 54 vs n = 16, p = 0.001), and Meckel's diverticulum cases appearing tubular were significantly higher than in other diverticulum cases (n = 25 vs n = 3, p < 0.001). CONCLUSION: CT allows for a higher detection rate of diverticular bleeding, even if asymptomatic, guiding classification into multiple potentially clinically relevant categories. CRITICAL RELEVANCE STATEMENT: Contrast-enhanced CT imaging is effective in determining the location and cause of non-neoplastic small bowel bleeding, especially diverticular bleeding. Therefore, the use of enhanced CT should be prioritized in the diagnosis and management of small bowel bleeding. KEY POINTS: CT has potential value in the diagnosis of small bowel bleeding. CT imaging suggests possible surgical intervention for active bleeding detection. CT diagnoses and localizes small bowel bleeding, aiding in treatment and prioritizing in guidelines.

Predictors for acute exacerbation of interstitial pneumonia following lung cancer surgery: a multicenter study.

BACKGROUND: Acute exacerbation (AE) of interstitial lung disease (ILD) is one of the most serious complications during perioperative period of lung cancer resection. This study aimed to investigate the correlation between preoperative 2- deoxy-2-[18F]fluoro-D-glucose (18F-FDG) PET/CT findings and AE in lung cancer patients with ILD. METHODS: We retrospectively reviewed the data of 210 patients who underwent lung resection for non-small cell lung cancer. Relationships between clinical data and PET images and AE were evaluated. The patients were divided into an AE(+) and an AE(-) group for multivariate logistic regression analysis. Receiver operating characteristic (ROC) curve analysis was conducted and the area under curve (AUC) was used to assess the predictive values. RESULTS: Among 210 patients, 48 (22.8%) were diagnosed with ILD based on chest CT. Among them, 9 patients (18.75%) developed AE after lung resection and were defined as AE(+) group. The course of ILD was longer in AE(+) group compared to AE(-) group. More patients in AE(+) group had a history of AE and chronic obstructive pulmonary disease (COPD) than in AE(-) group. The maximum standardized uptake value (SUVmax) of the noncancerous interstitial pneumonia (IP) area and cancers in AE(+) group was significantly higher compared to AE(-) group. Univariate logistic regression analysis showed that AE, COPD, SUVmax of the noncancerous IP area, SUVmax of cancer, surgical method were significantly correlated with AE. The course of ILD[OR(95%CI) 2.919; P = 0.032], SUVmax of the noncancerous IP area[OR(95%CI) 7.630;P = 0.012] and D-Dimer level[OR(95%CI) 38.39;P = 0.041] were identified as independent predictors for AE in patients with ILD after lung cancer surgery. When the three indicators were combined, we found significantly better predictive performance for postoperative AE than that of SUVmax of the noncancerous IP area alone [0.963 (95% CI 0.914-1.00); sensitivity, 100%, specificity 87.2%, P < 0.001 vs. 0.875 (95% CI 0.789 ~ 0.960); sensitivity, 88.9%, specificity, 76.9%, P = 0.001; difference in AUC = 0.088, Z = 1.987, P = 0.04]. CONCLUSION: The combination of the course of ILD, SUVmax of the noncancerous IP area and D-Dimer levels has high predictive value for the occurrence of AE in patients with concomitant interstitial lesions.

Differentiating low-risk thymomas from high-risk thymomas: preoperative radiomics nomogram based on contrast enhanced CT to minimize unnecessary invasive thoracotomy.

BACKGROUND: This study was designed to develop a combined radiomics nomogram to preoperatively predict the risk categorization of thymomas based on contrast-enhanced computed tomography (CE-CT) images. MATERIALS: The clinical and CT data of 178 patients with thymoma (100 patients with low-risk thymomas and 78 patients with high-risk thymomas) collected in our hospital from March 2018 to July 2023 were retrospectively analyzed. The patients were randomly divided into a training set (n = 125) and a validation set (n = 53) in a 7:3 ratio. Qualitative radiological features were recorded, including (a) tumor diameter, (b) location, (c) shape, (d) capsule integrity, (e) calcification, (f) necrosis, (g) fatty infiltration, (h) lymphadenopathy, and (i) enhanced CT value. Radiomics features were extracted from each CE-CT volume of interest (VOI), and the least absolute shrinkage and selection operator (LASSO) algorithm was performed to select the optimal discriminative ones. A combined radiomics nomogram was further established based on the clinical factors and radiomics scores. The differentiating efficacy was determined using receiver operating characteristic (ROC) analysis. RESULTS: Only one clinical factor (incomplete capsule) and seven radiomics features were found to be independent predictors and were used to establish the radiomics nomogram. In differentiating low-risk thymomas (types A, AB, and B1) from high-risk ones (types B2 and B3), the nomogram demonstrated better diagnostic efficacy than any single model, with the respective area under the curve (AUC), accuracy, sensitivity, and specificity of 0.974, 0.921, 0.962 and 0.900 in the training cohort, 0.960, 0.892, 0923 and 0.897 in the validation cohort, respectively. The calibration curve showed good agreement between the prediction probability and actual clinical findings. CONCLUSIONS: The nomogram incorporating clinical factors and radiomics features provides additional value in differentiating the risk categorization of thymomas, which could potentially be useful in clinical practice for planning personalized treatment strategies.

A 18F-FDG PET/CT based radiomics nomogram for predicting disease-free survival in stage II/III colorectal adenocarcinoma.

OBJECTIVES: This study aimed to establish a clinical nomogram model based on a radiomics signatures derived from 18F-fluorodeoxyglucose positron-emission tomography (18F-FDG PET/CT) and clinical parameters to predict disease-free survival (DFS) in patients with stage II/III colorectal adenocarcinoma. Understanding and predicting DFS in these patients is key to optimizing treatment strategies. METHODS: A retrospective analysis included 332 cases from July 2011 to July 2021 at The Sixth Affiliated Hospital, Sun Yat-sen University, with PET/CT assessing radiomics features and clinicopathological features. Univariate Cox regression, the least absolute shrinkage and selection operator (LASSO) Cox, and multivariable Cox regression identified recurrence-related radiomics features. We used a weighted radiomics score (Rad-score) and independent risk factors to construct a nomogram. Evaluation involved time-dependent receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA). RESULTS: The nomogram, incorporating Rad-score, pN, and pT demonstrated robust predictive ability for DFS in stage II/III colorectal adenocarcinoma. Training cohort areas under the curve (AUCs) were 0.78, 0.80, and 0.86 at 1, 2, and 3 years, respectively, and validation cohort AUCs were 0.79, 0.75, and 0.73. DCA and calibration curves affirmed the nomogram's clinical relevance. CONCLUSION: The 18F-FDG PET/CT based radiomics nomogram, including Rad-score, pN, and pT, effectively predicted tumor recurrence in stage II/III colorectal adenocarcinoma, significantly enhancing prognostic stratification. Our findings highlight the potential of this nomogram as a guide for clinical decision making to improve patient outcomes.