Journal of Computer Assisted Tomography最新文献

Objective: To evaluate whether our new protocol that uses a saline test injection and a leak detection sensor (LDS) reduces the frequency and amount of contrast media (CM) extravasation during the intravenous CM administration for CT.

Methods: This retrospective study included 20,342 patients who underwent CECT at our hospital from March 2021 to November 2021 (old protocol, direct patient observation, and CM injection pressure monitoring, n=10,529) and from March 2024 to November 2024 (new protocol, old protocol plus saline test injection, and the LDS attachment, n=9813). We compared the frequency and the volume of extravasation between the 2 protocols using the Fisher exact test and the Mann-Whitney U test. We also evaluated the accuracy of the LDS.

Results: Extravasation occurred in 51 patients (age 72.1±12.2 y, 33 men) under the old protocol and in 26 patients (age 73.6±9.0 y, 17 men) with the new protocol. The overall frequency of extravasation and the number of patients with an extravasation volume of at least 20 mL were significantly lower with the new protocol than the old protocol (0.48% vs. 0.26%; 0.16% vs. 0.03% all, P<0.01). The extravasation volume was significantly reduced with the new protocol (14 vs. 6 mL, P<0.01). The sensitivity of the LDS to detect extravasation of 3, 5, 10, and 15 mL was 50%, 88%, 93%, and 100%, respectively; specificity was 99% for all.

Conclusions: Our new protocol reduced the frequency and dose of CM extravasation.

Acquired diverticular disease of the small bowel is often seen in the duodenum. It is an uncommon but under-recognized entity in the jejunum and the ileum. Meckel's diverticulum, a true diverticulum arising in the distal ileum, although the most common congenital abnormality of the gastrointestinal tract, is rare and occurs in about 2% of the population. Most of the time, diverticular disease of the small bowel is asymptomatic. Common complications of small bowel diverticular disease include diverticulitis and hemorrhage. Diverticulitis of the small bowel is an uncommon cause of acute abdomen and may be misdiagnosed if not included in differential considerations based on the imaging features. Certain specific complications can occur related to the location of the diverticulum or due to other factors associated with the diverticulum. For example, obstructive jaundice (Lemmel syndrome) can occur in the setting of a duodenal diverticulum, and intestinal obstruction can occur in the setting of a Meckel's diverticulum. Familiarity with the different imaging manifestations of small bowel diverticular disease complications can help with appropriate diagnoses, thereby improving patient management.

Preoperative computed tomography (CT)-guided localization is widely used to facilitate the surgical resection of pulmonary nodules (PNs) through video-assisted thoracoscopic surgery (VATS). This meta-analysis aims to compare the clinical performance and safety profile of 2 commonly used localization techniques: the anchored needle (AN) and the hook-wire (HW) method. A systematic search was conducted using the PubMed, Wanfang, and Cochrane Library databases to identify relevant comparative studies. Key outcome measures were extracted and analyzed using Stata v12.0 and RevMan v5.3. Seven retrospective studies conducted in China met the inclusion criteria, encompassing a total of 1557 patients. Among these, 889 patients with 961 PNs underwent CT-guided AN localization, whereas 668 patients with 697 PNs received HW localization. Compared with HW, AN localization demonstrated a significantly higher rate of successful localization (P <0.001), lower rates of overall complications (P=0.01), pneumothorax (P=0.003), and pulmonary hemorrhage (P=0.004). Patients in the AN group also reported significantly lower pain scores (P <0.001). Two groups exhibited similar localization (P=0.48) and VATS (P=0.93) time. Notable heterogeneity was observed in localization time, complication rate, VATS time, and pain score (I²=91%, 73%, 94%, and 94%, respectively). No evidence of publication bias was detected across the analyzed outcomes. CT-guided AN localization seems to offer higher successful localization rate and a lower complication rate compared with HW localization for patients undergoing surgical management of PNs.

Objective: Changes in bone marrow fat content measured through relative fat fraction (rFF) obtained from dual-echo gradient-recalled echo (GRE) in- and opposed-phase (IOP) MRI have been proposed to evaluate treatment response for multiple myeloma. However, rFF suffers from several significant limitations that lead to inaccurate fat fraction measurements. In contrast, proton density fat fraction (PDFF) is the most objective and validated MRI metric of tissue fat content, and it is measured through confounder-corrected, multiecho, chemical-shift-encoded (CSE) MRI. The purpose of this study was to evaluate the linearity and bias of bone marrow rFF compared with PDFF.

Methods: This single-center, retrospective study included 100 patients who underwent clinical MRI for liver fat/iron quantification at 1.5T and 3.0T (50 exams/patients for each field strength), which included dual-echo GRE IOP and commercial multiecho CSE MRI (IDEAL-IQ). One region of interest (ROI) was placed in each of the T12, L1, and L2 vertebral bodies. Per-ROI rFF was calculated using (SIP and SOP = signal intensities on IP and OP images, respectively). rFF was correlated with PDFF using linear regression and coefficient of determination (R2). Bland-Altman analysis evaluated rFF bias across the observed range for R2* and PDFF; mean bias and 95% limits of agreement (LOA) were reported.

Results: Bone marrow rFF demonstrated no linearity against PDFF at 1.5T or at 3.0T (R2 = 0.032 and 0.057, respectively). Moreover, bone marrow rFF demonstrated significant bias with respect to PDFF at 1.5T and 3.0T, with significant bias that increases directly with bone marrow fat fraction.

Conclusions: Bone marrow rFF is nonlinear and variably biased compared with PDFF and should not be used in research or clinical settings.

Objectives: To evaluate the feasibility of generating high-resolution CT-like bone images from shoulder 3D-VIBE CAIPIRINHA Dixon MRI using vendor-independent deep-learning reconstruction.

Methods: This IRB-approved retrospective study included patients who underwent shoulder MRI and CT between January 2023 and 2024. MRI was performed on a 3.0-T system with a dedicated coil. Patients with study dates >6 months apart or poor image quality were excluded. A 3D multiecho VIBE CAIPIRINHA-Dixon sequence was postprocessed with a DL-based tool. In-phase and opposed-phase images before (Ori-In, Ori-Op) and after DL processing (DL-In, DL-Op) were evaluated by 2 musculoskeletal radiologists for pathology, anatomic visibility, artifacts, and glenoid dimensions, using a Likert scale. CT served as the gold standard. Relative contrast-to-noise (rCNR) and signal-to-noise ratios (rSNR) were assessed by radiologists and a computer scientist. Statistical tests included Friedman, Wilcoxon Rank, Kruskal-Wallis, and intraclass correlation coefficients.

Results: Ninety-nine patients (52 males, 47 females; age range: 17-87) were included. Cortical visibility score of humerus was significantly higher in DL-Op [median value: 2.75, interquartile range (IQR): 1.5 to 3.5 than Ori: 2 (1.5 to 2.44), P<0.001]. Trabecular score was higher on DL-In and Op (2.63 and 2.75) than Ori (2, P<0.001). DL-In images had the minimal artifacts [2 (1.5 to 2.38)] with the best rSNR (humerus: 110.82; glenoid: 92.14) and rCNR (humerus: 39.45; glenoid: 21.40). Ori-In underestimated longitudinal diameter compared with CT (P=0.046); transverse diameters were similar across sequences. The median DL-in and DL-op scores of rotator cuff calcification were 2.38 (IQR: 2.5 to 3.06) and 2.25 (2.06 to 2.94), significantly higher compared with the 1.25 (1 to 2.75) of fat-saturated T2WI. Inter-reader agreement ranged from 0.62 to 0.82 (P<0.001).

Conclusions: DL-3D-VIBE CAIPIRINHA Dixon MRI can generate high-quality CT-like images of shoulder joint, providing a potential for a radiation-free bone imaging.

Objectives: This study aims to evaluate various large language models (LLMs) for their effectiveness in answering Japan Radiology Board Examination (JRBE).

Materials and methods: A total of 315 examination questions from 2021 to 2023 JRBE were administered to 14 LLMs, comprising 7 open-source and 7 closed-source models. Each model processed the questions in their original Japanese language and after translating them into English by LLMs themselves. Performance metrics, including median scores, interquartile ranges (IQR), P-values, and correlation coefficients, were analyzed using Python.

Results: Closed-source models achieved a higher median correct response rate of 44.28% (IQR: 32.38%-53.02%) compared with open-source models at 29.52% (IQR: 24.76%-36.67%), exhibiting a 50.2% improvement (P < 0.001). Translating questions to English improved performance, with median scores increasing from 33.02% (IQR: 27.86%-43.65%) to 40.00% (IQR: 27.54%-46.27%), representing a 21.1% increase (P = 0.005). A positive correlation was observed between the cost per 1M tokens and accuracy (Japanese: r = 0.623, P = 0.017; English: r = 0.613, P = 0.020). No significant correlation was found between model release dates and performance. Only the high-cost closed-source models, GPT-4 and Claude-3-Opus, surpassed the 60% passing threshold by Japanese Medical Specialty Board when using English translation. Among open-source models, LLama-3-70B demonstrated notable performance improvements compared with its predecessors.

Conclusions: Closed-source, high-end LLMs exhibit superior performance in JRBE, and translating questions into English by themselves further enhances their accuracy. There is a significant positive correlation between the cost of LLMs and their performance, whereas the release date does not significantly influence their performance.

Objectives: At present, the study of bronchiolar adenoma (BA) mainly focuses on its pathologic characteristics, but there is limited understanding of its clinical manifestations and imaging signs. This article aims to summarize the clinical manifestations and imaging features of 80 cases of BA, with the goal of achieving a comprehensive and systematic understanding of BA.

Materials and methods: We retrospectively analyzed 80 patients with BA confirmed by surgical pathology in our hospital. All subjects underwent thin-slice CT examination. The basic information, tumor history, clinical manifestations, and CT imaging features of the lesions were collected. The subjects' age, maximum diameter of BA, and shortest distance from the pleura were analyzed by t -test or 1-way ANOVA, while other clinical and radiologic characteristics were compared for differences among different BA types by the χ 2 test or Fisher exact probability method.

Results: The majority of the 80 patients were female, with an average age of 59.08±10.16 years. The majority of them do not manifest any clinical symptoms. All lesions are located in the subpleural area, including 63 cases in the lower lobe of the lungs. The average size of the tumors was 10.31±5.01 mm. The majority of the lesions exhibited irregular morphology (53 cases, 66.25%) and predominantly comprised solid nodules (46 cases, 57.50%). There were statistically significant differences in lesion morphology, boundary, and pseudocavity among pure ground-glass nodular BA, mixed ground-glass nodular BA, and solid density nodular BA. Compared with pure ground-glass density BA (1 case, 1.25%) and mixed ground-glass density BA (7 cases, 8.75%), the boundary of solid nodules BA (42 cases, 52.50%) was significantly clearer ( P <0.001). The presence of pseudocavity was found to be significantly higher in individuals with solid nodules compared with those with pure ground-glass nodules ( P <0.0167). Compared with BA without pseudocavity, BA with pseudocavity exhibited a clearer lung interface ( P <0.001), more abnormal vessel signs ( P =0.007), and a higher incidence of malignant preoperative diagnosis ( P =0.020).

Conclusions: BA mostly occurs in middle-aged and elderly women without any clinical symptoms. The imaging manifestations of BA are diverse, mainly presenting as irregular solid nodules. The interface between the tumor and lung is clear, and pseudocavity formation is common. In addition, BA with pseudocavity often exhibits abnormal vascular signs, which can lead to misdiagnosis as malignancy before surgery.

Objectives: This study aimed to develop a multiregional radiomics-based model using multisequence MRI to predict microvascular invasion in hepatocellular carcinoma.

Methods: We enrolled 141 patients with hepatocellular carcinoma, including 61 with microvascular invasion, who were diagnosed between March 2017 and July 2022. Clinical data were compared using the Wilcoxon rank-sum test or χ 2 test. Patients were randomly divided into training (n=112, 80%) and test (n=29, 20%) data sets. Four MRI sequences-including T2-weighted imaging, T2-weighted imaging with fat suppression, arterial phase-contrast enhancement, and portal venous phase contrast enhancement-were used to build the radiomics model. The tumor volumes of interest were manually delineated, and the expand-5 mm and expand-10 mm volumes of interest were automatically generated. A total of 1409 radiomic features were extracted from each volume of interest. Feature selection was performed using the least absolute shrinkage and selection operator and Spearman correlation analysis. Three logistic regression models (Tumor, Tumor-Expand5, and Tumor-Expand10) were established based on the radiomic features. Model performance was assessed using receiver operating characteristic analysis and Delong's test.

Results: Maximum tumor diameter, hepatitis B virus DNA, and aspartate aminotransferase levels were significantly different between the groups. The Tumor-Expand5mm model exhibited the best performance among the 3 models, with areas under the curve of 0.90 and 0.84 in the training and test data sets.

Conclusions: The Tumor-Expand5 model based on multisequence MRI shows great potential for predicting microvascular invasion in patients with hepatocellular carcinoma, and may further contribute to personal clinical decision-making.

Objective: This study aimed to compare computed tomography (CT)/magnetic resonance imaging (MRI) characteristics of acute pancreatitis (AP) between patients with cholecystectomy and non-cholecystectomy and to validate the effect of prior cholecystectomy on the severity of subsequent pancreatitis.

Methods: This retrospective study included 384 inpatients with AP at our hospital from January 1, 2020 to December 31, 2023. Based on their history of cholecystectomy, the patients were split into cholecystectomy and non-cholecystectomy groups. propensity score matching was applied, considering age and sex, in a 1:3 ratio. Demographic, clinical, laboratory, and CT/MRI parameters of each group were analyzed.

Results: There were 200 (52.1%) males and 184 (47.9%) females, with a mean age of 53.55 ± 13.86 years (range: 18-98 y). Ninety-six patients were in the cholecystectomy group that had previously undergone cholecystectomy, and 288 in the non-cholecystectomy group. Creatinine and C-reactive protein levels were lower in the patients with cholecystectomy than in patients with non-cholecystectomy ( P 1 = 0.001, P 2 = 0.049). In the prevalence of biliary pancreatitis, the cholecystectomy patients are 27.1%, whereas the non-cholecystectomy patients are 45.8% ( P = 0.005). The non-cholecystectomy patients had a significantly higher mean CT/MRI severity index score (3.57 ± 1.72 points) than the cholecystectomy group (3.00 ± 1.58 points; P < 0.001). Regarding local complications, In the groups that underwent cholecystectomy and those that did not, the prevalence of acute peripancreatic fluid collection was 40.4% and 21.9%, respectively. ( P < 0.001).

Conclusions: AP following cholecystectomy exhibits unique imaging characteristics. Cholecystectomy reduces the severity and acute peripancreatic fluid collection rate of subsequent pancreatitis on CT/MRI.

Objective: Incomplete partition type II (IP-II) is one of the most common inner ear malformations that necessitates cochlear implantation. It is characterized by a cystic cochlear apex resulting from the coalescence of middle and apical turns due to modiolar hypoplasia and distal interscalar septal defect. Radiologic diagnosis of IP-II anomaly could be difficult with equivocal changes in tiny labyrinthine structures, especially with inexperienced observers. In our study, we aimed to determine pertinent quantitative radioanatomical measurements of inner ear structures (lateral interscalar notch angle, lateral interscalar notch depth, and lateral height) that may contribute to the diagnosis of IP-II anomaly using temporal bone high-resolution computed tomography (HRCT).

Methods: Our study was a retrospective case-control study approved by the institutional review board. We retrospectively reviewed temporal bone HRCT examinations for the preoperative assessment of cochlear implantation of patients with sensorineural hearing loss (SNHL), using the diagnosis code of IP-II anomaly. Patients with SNHL and a radiologic diagnosis of IP-II anomaly according to the Sennaroglu classification were recruited. Thirty-four SNHL patients with IP-II anomaly (66 ears) and 24 patients without SNHL (48 ears) who underwent temporal CT imaging for inflammatory conditions or trauma not involving labyrinthine structures were included in the study. The lateral interscalar notch angle, lateral interscalar notch depth, and lateral height were independently measured by 2 observers (a senior head and neck radiologist and a novice radiologist). The parameters measured in patient and control groups were compared using the Mann-Whitney U test, and interobserver reliability was calculated.

Results: Lateral interscalar notch angle and lateral height values were found to be significantly larger, while lateral interscalar notch depth value was significantly smaller in the IP-II group ( P <0.05). The agreement between the observers in all measurements, evaluated separately in IP-II and control groups, was excellent ( P <0.05). The cutoff values for determining the IP-II anomaly were found to be consistent between the 2 observers, with high sensitivity and specificity.

Conclusions: CT measurements of inner ear structures in SNHL could help to diagnose IP-II anomalies, especially in patients with equivocal audiological and radiologic findings. This study validates CT measurements in the evaluation of IP-II anomaly conducted by histologic specimens and MRI in previous studies. Lateral cochlear measurements with an angle of >130 degrees, a depth of ≤0.35 mm, and a height of >3.15 mm could support the diagnosis of the IP-II anomaly. These measurements are also reproducible.