Compare Computed Tomography Images Research Articles

Pre-procedure 18F-FDG PET/CT imaging improves the performance of CT-guided transthoracic biopsy

To compare computed tomography (CT)-guided transthoracic lung biopsies (CTLB) with and without pre-procedure 18F-fludeoxyglucose positron emission tomography (18F-FDG PET)/CT images in the diagnosis of pulmonary nodules/masses. This is a case-control study in a single center. The data of patients with a transthoracic lung biopsy guided by CT and pre-procedure 18F-FDG PET/CT (group 2, here called the “PETCTLB” group), including demographics, clinical characteristics, and biopsy-related parameters, were collected. The PET/CT scan was performed within 15 days before the biopsy. The data from patients with CTLB were used as controls (group 1). Biopsies for all patients were performed by the same physician between January 2019 and December 2021. The final diagnosis was based on surgical outcomes, or imaging findings, and the results of at least one 6-month follow-up. The demographics and clinical characteristics of patients, lesions and biopsy-related variables, diagnostic yields, and incidence of complications were compared between the two groups. Two-tailed t-tests were used to compare the mean values in the two independent groups, while categorical variables were compared using the Pearson chi-squared test, and P values < 0.05 were considered to be significant. A total of 84 patients were included, and 84 biopsies of 84 lung nodules/masses were analyzed. The demographics and clinical characteristics of group 2 (n = 39; 21 men; mean age, 63.2 ± 9.29 years) and group 1 (n = 45; 30 men; mean age, 61.2 ± 12.3 years) had no significant difference (P = 0.230 and 0.397, respectively). The procedure duration (11.1 ± 3.0 vs. 12.9 ± 3.3 minutes, P = 0.008), the number of samples (2.6 ± 0.5 vs. 3.1 ± 0.4, P < 0.001), diagnostic accuracy (97.4% vs. 82.2%, P = 0.033), and bleeding complication (25.6% vs. 42.2%, P = 0.034) of group 2 and group 1 were statistically different. A biopsy guided by CT plus pre-procedure 18F-FDG PET/CT (PETCTLB) is a safe procedure that can provide a precise diagnosis in the majority of lung nodules/masses. It has better diagnostic performance than CTLB.

Correlation Between Computed Tomography Findings and the Laboratory Test-Derived Severity Score in Patients With Severe Acute Alcoholic Hepatitis.

This study aimed to compare computed tomography (CT) findings between patients with severe and nonsevere acute alcoholic hepatitis (AAH). We included 96 patients diagnosed with AAH between January 2011 and October 2021 who underwent 4-phase liver CT and laboratory blood tests. Two radiologists reviewed the initial CT images with respect to distribution and grade of hepatic steatosis; transient parenchymal arterial enhancement (TPAE); and presence of cirrhosis, ascites, and hepatosplenomegaly. A Maddrey discriminant function score (4.6 × [patient's prothrombin time - control] + total bilirubin [mg/mL]) was used as cutoff indicator for severity, with a score of 32 or higher indicating severe disease. The image findings were compared between the severe (n = 24) and nonsevere (n = 72) groups using the χ 2 test or Fisher exact test. After univariate analysis, the most significant factor was identified using a logistic regression analysis. In the univariate analysis, there were significant between-group differences in the TPAE, liver cirrhosis, splenomegaly, and ascites ( P < 0.0001, P < 0.0001, P = 0.0002, and P = 0.0163, respectively). Among them, TPAE was the only significant factor for severe AAH ( P < 0.0001; odds ratio, 48.1; 95% confidence interval, 8.3-280.6). Using this single indicator, the estimated accuracy, positive predictive, and negative predictive values were 86%, 67%, and 97%, respectively. Transient parenchymal arterial enhancement was the only significant CT finding in severe AAH.

Computed tomography-based radiomics machine learning classifiers to differentiate type I and type II epithelial ovarian cancers.

To compare computed tomography (CT)-based radiomics for preoperatively differentiating type I and II epithelial ovarian cancers (EOCs) using different machine learning classifiers and to construct and validate the best diagnostic model. A total of 470 patients with EOCs were included retrospectively. Patients were divided into a training dataset (N = 329) and a test dataset (N = 141). A total of 1316 radiomics features were extracted from the portal venous phase of contrast-enhanced CT images for each patient, followed by dimension reduction of the features. The support vector machine (SVM), k-nearest neighbor (KNN), random forest (RF), naïve Bayes (NB), logistic regression (LR), and eXtreme Gradient Boosting (XGBoost) classifiers were trained to obtain the radiomics signatures. The performance of each radiomics signature was evaluated and compared by the area under the receiver operating characteristic curve (AUC) and relative standard deviation (RSD). The best radiomics signature was selected and combined with clinical and radiological features to establish a combined model. The diagnostic value of the combined model was assessed. The LR-based radiomics signature performed well in the test dataset, with an AUC of 0.879 and an accuracy of 0.773. The combined model performed best in both the training and test datasets, with AUCs of 0.900 and 0.934 and accuracies of 0.848 and 0.823, respectively. The combined model showed the best diagnostic performance for distinguishing between type I and II EOCs preoperatively. Therefore, it can be a useful tool for clinical individualized EOC classification. • Radiomics features extracted from computed tomography (CT) could be used to differentiate type I and II epithelial ovarian cancers (EOCs). • Machine learning can improve the performance of differentiating type I and II EOCs. • The combined model exhibited the best diagnostic capability over the other models in both the training and test datasets.

Preoperative planning using computed tomography in tibial plateau levelling osteotomy: A comparison with conventional radiography.

BackgroundTibial plateau levelling osteotomy (TPLO) is currently one of the most common surgical procedures for the correction of the stifle joint with a ruptured cranial cruciate ligament. TPLO is based on the preoperative tibial plateau angle (TPA); therefore, it is essential to optimise the consistency and repeatability of TPA measurements.ObjectivesThis study aims to compare computed tomography (CT) with conventional radiography in the preoperative planning of TPLO.MethodsThis prospective study included six dogs (12 hindlimbs) and 13 canine cadaveric hindlimbs. In the six beagle dogs, TPAs were measured by three radiologists using digital radiographic and CT images to evaluate the intra‐ and inter‐observer agreement. To evaluate the intra‐observer agreement of the TPA before and after surgery, and the intended angle of the postoperative TPA according to the preoperative planning method, 13 cadaveric hindlimbs were evaluated thrice at random by a single radiologist.ResultsThe intra‐ and inter‐observer intraclass correlation coefficients (ICCs) of the CT method were higher than those of the radiographic method in normal beagle dogs. The intra‐observer ICC of the CT method before and after TPLO was generally higher than that of the radiographic method in the cadaver. However, no significant difference was noted in the evaluation of the intended postoperative TPA according to the preoperative planning method.ConclusionsThe intra‐ and inter‐observer ICCs allowed for easy identification of landmarks required to consistently determine the TPA in the preoperative planning of TPLO based on CT images.

Periosteal reaction of medication-related osteonecrosis of the jaw (MRONJ): clinical significance and changes during conservative therapy.

We previously reported that the periosteal reaction (PR) in medication-related osteonecrosis of the jaw (MRONJ) is a poor prognostic factor in surgical cases, but it is not clear how PR changes during conservative therapy. The purpose of this retrospective study was to compare computed tomography (CT) findings at the first visit and during follow-up visits in MRONJ patients subjected to conservative therapy and to investigate factors associated with the exacerbation of PR during conservative therapy. Sixteen patients with MRONJ of the lower jaw who underwent conservative therapy and experienced a PR on CT images at the first visit and underwent CT examination again after 6 months or more were enrolled in the study. Clinical features and CT findings (extent of osteolytic lesion, extent of PR, type of PR, and changes during conservative treatment) were investigated. On the second CT scan, the osteolytic lesion improved in 4 patients, had not changed in 5, and deteriorated in 7, whereas the PR improved in 5 patients, had not changed in 4, and deteriorated in 7 patients. PR was significantly deteriorated in patients who continued to receive antiresorptive agents during conservative treatment and in patients with deteriorated osteolytic lesions. PR in MRONJ often expands during conservative therapy and the PR type progresses from the attached type to the gap type, and the irregular type, but discontinuation of antiresorptive agent may improve PR as well as osteolytic lesions.

Image quality comparison of a nonlinear image-based noise reduction technique with a hybrid-type iterative reconstruction for pediatric computed tomography

PurposeTo compare computed tomography (CT) image properties between a vendor-independent image-based noise reduction technique, Image-space Noise Reduction (iNoir) and a hybrid-type iterative reconstruction technique, Adaptive Statistical Iterative Reconstruction (ASIR). MethodsA cylindrical water phantom, corresponding to pediatric body size, containing soft-tissue-equivalent rod and 12-mg iodine/ml rod was scanned at size-specific dose estimates of 8.4 and 16.7 mGy. For assessments of image quality and noise texture change, task-based system performance function (SPF) and peak frequency difference (PFD) were compared, respectively, among filtered back projection (FBP), IR image with 50%-blending rate (50%ASIR), 100%ASIR, 50%iNoir, and 100%iNoir. Human observer test for pediatric CT images was performed by radiologists. ResultsFor the soft-tissue contrast, SPF2 of 100%iNoir was the highest. The average SPF2 between 0.1 and 0.5 cycles/mm for 100%iNoir increased by approximately 70% compared with FBP, while ASIR indicted slight increases in the frequency region of >0.2 cycles/mm. For the iodine contrast, 100%iNoir indicated highest values at the spatial frequencies corresponding pediatric artery diameters. The PFDs of iNoir were negligible and lower than that of ASIR. The results of human observer test supported results of SPF2 and PFD. ConclusionsCompared with ASIR, iNoir provided better image quality for pediatric abdominal CT without compromising noise texture change.

Response evaluation of giant-cell tumor of bone treated by denosumab: Histogram and texture analysis of CT images

This study aimed to compare computed tomography (CT) features, including tumor size and textural and histogram measurements, of giant-cell tumors of bone (GCTBs) before and after denosumab treatment and determine their applicability in monitoring GCTB response to denosumab treatment. This retrospective study included eight patients (male, 3; female, 5; mean age, 33.4 years) diagnosed with GCTB, who had received treatment by denosumab and had undergone pre- and post-treatment non-contrast CT between January 2010 and December 2016. This study was approved by the institutional review board. Pre- and post-treatment size, histogram, and textural parameters of GCTBs were compared by the Wilcoxon signed-rank test. Pathological findings of five patients who underwent surgery after denosumab treatment were evaluated for assessment of treatment response. Relative to the baseline values, the tumor size had decreased, while the mean attenuation, standard deviation, entropy (all, P=0.017), and skewness (P=0.036) of the GCTBs had significantly increased post-treatment. Although the difference was statistically insignificant, the tumors also exhibited increased kurtosis, contrast, and inverse difference moment (P=0.123, 0.327, and 0.575, respectively) post-treatment. Histologic findings revealed new bone formation and complete depletion or decrease in the number of osteoclast-like giant cells. The histogram and textural parameters of GCTBs changed significantly after denosumab treatment. Knowledge of the tendency towards increased mean attenuation and heterogeneity but increased local homogeneity in post-treatment CT histogram and textural features of GCTBs might aid in treatment planning and tumor response evaluation during denosumab treatment.

Computed tomography and magnetic resonance imaging findings of nasal cavity hemangiomas according to histological type.

ObjectiveTo compare computed tomography (CT) and magnetic resonance imaging (MRI) findings between two histological types of nasal hemangiomas (cavernous hemangioma and capillary or lobular capillary hemangioma).Materials and MethodsCT (n = 20; six pre-contrast; 20 post-enhancement) and MRI (n = 7) images from 23 patients (16 men and seven women; mean age, 43 years; range, 13-73 years) with a pathologically diagnosed nasal cavity hemangioma (17 capillary and lobular capillary hemangiomas and six cavernous hemangiomas) were reviewed, focusing on lesion location, size, origin, contour, enhancement pattern, attenuation or signal intensity (SI), and bony changes.ResultsThe 17 capillary and lobular hemangiomas averaged 13 mm (range, 4-37 mm) in size, and most (n = 13) were round. Fourteen capillary hemangiomas had marked or moderate early phase enhancement on CT, which dissipated during the delayed phase. Four capillary hemangiomas on MRI showed marked enhancement. Bony changes were usually not seen on CT or MRI (seen on five cases, 29.4%). Half of the lesions (2/4) had low SI on T1-weighted MRI images and heterogeneously high SI with signal voids on T2-weighted images. The six cavernous hemangiomas were larger than the capillary type (mean, 20.5 mm; range, 10-39 mm) and most had lobulating contours (n = 4), with characteristic enhancement patterns (three centripetal and three multifocal nodular), bony remodeling (n = 4, 66.7%), and mild to moderate heterogeneous enhancement during the early and delayed phases.ConclusionCT and MRI findings are different between the two histological types of nasal hemangiomas, particularly in the enhancement pattern and size, which can assist in preoperative diagnosis and planning of surgical tumor excision.

439P - Comparison of Ct and 18F-Flt Pet/Ct Imaging for Target Volume Delineating in Patients with Glioma

ABSTRACT Aim: The aim of this pilot study was to compare computed tomography (CT) and 3′-deoxy-3′-[18F] fluorothymidine (18F-FLT) positron emission tomography/ computed tomography (PET/CT) imaging for gross tumor volume (GTV) and clinical target volume (CTV) delineation, and to analyze the impact of proliferative tumor volume delineated by 18F-FLT PET/CT. Methods: 12 patients with glioma were enrolled into this study. The relation of 18F-FLT uptake and pathology, Ki-67 index were studied in 9 patients. All of the 12 patients underwent 18F-FLT PET/CT imaging before radiotherapy. The enhanced CT images and 18F-FLT PET/CT images were all transferred to planning system and the target volumes from each image were delineated and compared. Results: 18F-FLT PET/CT SUVmax increased significantly with glioma grade (p = 0.007). SUVmax of 18F-FLT PET/CT (p= 0.03), T/N ratio (p Conclusions: The uptakes of 18F-FLT were positively correlated with grade of glioma and tumor cell proliferation index. To delineate target volume by 18F-FLT PET/CT imaging, the GTV and CTV are smaller than CT. It maybe improves the accuracy of GTV and CTV in patients with glioma and, meanwhile, provides potential benefits to normal brain tissue. Disclosure: All authors have declared no conflicts of interest.

CT sensitivities for large (≥3cm) adrenal adenoma and cortical carcinoma.

To retrospectively compare computed tomography (CT) sensitivities of large (≥3cm) adenoma and cortical carcinoma. Between January 2004 and November 2012, 43 non-oncologic patients with 43 adrenal masses [31 large adenomas, and 12 carcinomas] underwent unenhanced CT, early contrast-enhanced CT, and delayed contrast-enhanced CT scans prior to adrenalectomy. Three types of region-of-interest (ROI) were used on early contrast-enhanced CT images:aROI (large ROI) covering more than half of a mass and two small ROIs fitted to the highest (high ROI) or lowest (low ROI) attenuation area. These ROIs were also placed in the same area on the other CT images. Adenoma was diagnosed if a mass measured≤10 HU on unenhanced CT image, or if it had≥60% absolute percentage washout (APW)or≥40% relative percentage washout (RPW).Carcinoma was diagnosed if a mass had<60% APW and<40% RPW. CT sensitivities for large adenoma and carcinoma were compared. CT sensitivities for large adenoma vs. carcinoma were 64.5% (20/31) vs. 100% (12/12) using a large ROI, 100% (31/31) vs. 50.0% (6/12) using a high ROI, and 51.6% (16/31) vs. 100% (12/12) using a low ROIs, respectively. CT sensitivities for large adenoma and cortical carcinoma are influenced by the size or location of an ROI.A large ROI helps to minimize loss of CT sensitivity for large adenoma and to detect carcinoma.

Comparison of CT-Guided Percutaneous Biopsy with and Without Registration of Prior PET/CT Images to Diagnose Mediastinal Tumors

To compare computed tomography (CT)-guided percutaneous biopsy with and without registration of prior positron emission tomography (PET)/CT images in the diagnosis of mediastinal tumors. We performed clinically indicated percutaneous biopsy in 106 patients with mediastinal tumors in the anterior (n = 61), posterior (n = 21), middle (n = 16), and superior mediastinum (n = 8). The final diagnosis was based on surgical outcomes, or imaging findings and the results of at least 6-month follow-up. The patients underwent CT-guided percutaneous biopsy with (group 1, n = 56) or without (group 2, n = 50) registration of prior PET/CT images obtained no more than 22 days earlier. The registered images were used to plan the procedure and help target the tumors. CT-guided percutaneous needle biopsy yielded adequate samples in 101 of 106 (95 %) patients (group 1, n = 53; group 2, n = 48); in 95 patients (94 %), the diagnosis was confirmed by specific histological typing (group 1, n = 51; group 2, n = 44). The diagnostic accuracy of CT-guided percutaneous biopsy with and without the registration of prior PET/CT images was not statistically different (group 1, 96 %; group 2, 93 %, p = 0.324). CT-guided percutaneous biopsy is an easy and safe procedure that can provide a precise diagnosis in the majority of mediastinal tumors. PET/CT-guided biopsy yielded no special diagnostic advantages.

Computed tomography for the detection of thumb base osteoarthritis: comparison with digital radiography

To compare computed tomography (CT) with digital radiography for the detection of osteoarthritis (OA) of the first carpometacarpal (CMC1) and scaphotrapeziotrapezoid (STT) joint. We retrospectively identified patients who were assessed for CMC1 OA or STT OA at our hand surgery outpatient clinic between January 2008 and March 2011, and who had both a digital radiograph and a CT scan of the hand within a 3-month period. CT and radiographic images were scored independently by two musculoskeletal radiologists for joint space narrowing (JSN), osteophytes, subchondral sclerosis, bone cysts, and erosions in the CMC1 and STT joints. Thirty patients were identified. The inter-reader reliability of CT for the detection of CMC1 OA (ICC 1.00) and STT OA (ICC 0.80) was higher than radiography (ICC's 0.15 and 0.45). In comparison with their own radiographical scoring, both readers detected with CT 3 more patients with CMC1 OA, and 13 and 5 more patients with STT OA. Computed tomography had a higher inter-reader reliability and detection rate for both CMC1 and STT OA, compared with radiography. As surgical treatment selection of thumb base OA depends on the presence of pathology in the CMC1 and STT joints, CT may improve treatment selection and surgical planning.

Local Recurrence at the Bronchial Stump Site of Post-Operative Non-Small Cell Lung Cancer Patients: Comparison of CT Findings and Bronchoscopy

Purpose: To compare computed tomography (CT) images and bronchoscopic findings of local tumor recurrence at the bronchial stump site in post-operative non-small cell lung cancer (NSCLC) patients. Materials and Methods: A retrospective study was conducted to review the CT images of 9 lung cancer cases that recurred at the bronchial stump site on 576 resected primary non-small cell lung cancers over a 9-year period. The CT images of the bronchial stump site recurrence were classified as: bronchial wall thickening, nodular or endobronchial polypoid lesion, multiplicity, and enhancement patterns. We classified the bronchoscopic findings based on the revised classification by the Japan Lung Cancer Society. Results: The histologic types of the 9 cases of lung cancer that recurred, included 7 squamous cell carcinomas, 1 adenocarcinoma, and 1 adenoid cystic carcinoma. The CT findings included bronchial wall thickening with nodules (n = 6) and endobronchial polypoid nodules (n = 3) with heterogeneous enhancement. The CT findings were further classified as nodular infiltrating type (n = 5), polypoid type (n = 3) and superficial infiltrating type (n = 1) on bronchoscopy. Conclusion: Both a bronchoscopy and CT can be used as a complementary or alternative tool in evaluating bronchial stump site recurrences.

Comparison of CT and PET-CT based planning of radiation therapy in locally advanced pancreatic carcinoma

BackgroundTo compare computed tomography (CT) with co-registered positron emission tomography-computed tomography (PET-CT) as the basis for delineating gross tumor volume (GTV) in unresectable, locally advanced pancreatic carcinoma (LAPC).MethodsFourteen patients with unresectable LAPC had both CT and PET images acquired. For each patient, two three-dimensional conformal plans were made using the CT and PET-CT fusion data sets. We analyzed differences in treatment plans and doses of radiation to primary tumors and critical organs.ResultsChanges in GTV delineation were necessary in 5 patients based on PET-CT information. In these patients, the average increase in GTV was 29.7%, due to the incorporation of additional lymph node metastases and extension of the primary tumor beyond that defined by CT. For all patients, the GTVCT versus GTVPET-CT was 92.5 ± 32.3 cm3 versus 104.5 ± 32.6 cm3 (p = 0.009). Toxicity analysis revealed no clinically significant differences between two plans with regard to doses to critical organs.ConclusionCo-registration of PET and CT information in unresectable LAPC may improve the delineation of GTV and theoretically reduce the likelihood of geographic misses.

PET-CT Fusion in Radiation Management of Patients with Anorectal Tumors

To compare computed tomography (CT) with positron emission tomography-CT (PET-CT) scans with respect to anorectal tumor volumes, correlation in overlap, and influence on radiation treatment fields and patient care. From March to November 2003, 20 patients with rectal cancer and 3 patients with anal cancer were treated with preoperative or definitive chemoradiation, respectively. Computed tomography simulation data generated a CT gross tumor volume (CT-GTV) and CT planning target volume (CT-PTV) and (18)F-fluoro-2-deoxy-glucose PET (FDG-PET) created a PET-GTV and PET-PTV. The PET-CT and CT images were fused using manual coregistration. Patients were treated with three-dimensional conformal therapy to traditional doses. The PET, CT, and overlap volumes (OVs) were measured in cubic centimeters. Mean PET-GTV was smaller than the mean CT-GTV (91.7 vs. 99.6 cm(3)). The mean OV was 46.7%. As tumor volume increased, PET and CT OV correlated significantly (p < 0.001). In 17% of patients PET-CT altered the PTV, and in 26% it changed the radiation treatment plan. For 25% of patients with rectal cancer, PET detected distant metastases and changed overall management. Ten rectal cancer patients underwent surgery. When the pretreatment PET standardized uptake value was >10 and the posttreatment PET standardized uptake value was <6, 100% achieved pathologic downstaging (p = 0.047). Variation in volume was significant, with 17% and 26% of patients requiring a change in treatment fields and patient management, respectively. Positron emission tomography can change the management for anorectal tumors by early detection of metastatic disease or disease outside standard radiation fields.

Tarsal coalition: depiction and characterization with CT and MR imaging.

To compare computed tomography (CT) and magnetic resonance (MR) imaging in the detection, localization, and characterization of tarsal coalitions. Preoperative CT and MR images were obtained for 10 feet in nine patients (eight male and one female patients), aged 11-18 years who were unresponsive to conservative therapy. Results from two blinded readers were compared with results from surgery. Five calcaneonavicular and four medial subtalar coalitions were found at surgery. One patient had synovitis. CT depicted six coalitions and four were characterized correctly, but the fibrous coalitions were not characterized correctly. MR depicted all coalitions and seven were characterized correctly, including the fibrous coalitions. At MR imaging, proliferative synovitis was incorrectly characterized as a fibrous coalition. These results suggest that MR imaging depicts all coalitions but may not be able to help differentiate synovitis from fibrous coalitions and that CT has limitations in the depiction of fibrous coalitions.