Acta radiologica open最新文献

Background: Bedside insertion of peripherally inserted central venous catheter (PICC) is still needed in the various clinical settings. For this procedure, the accuracy of predicting the PICC catheter length is important, however, only a few methods have been proposed so far.

Purpose: A new formula using pre-procedural chest X ray (pre-CXR) was validated for placing the PICC catheter tip precisely in the actual clinical setting.

Material and methods: The formula predicting the PICC catheter length was formed by the hybrids of the calculated expression in the thorax and the actual measurement of the outer arm. The predicted length in the thorax was based on the half ellipse formed by the three landmarks on the pre-CXR. Prospectively, this formula was applied in the 110 patients. The results were compared to those in the traditional anthropometrical measurements (TAM) in the 48 patients.

Results: The discrepancy of the catheter distance from the carina and the variance of the tip position were smaller by using the Formula than by the TAM (P = .00053 and P = .038). Comparing to the other patient's valuables, the Formula had the strongest correlation coefficient with the true PICC length (r = 0.787). Evaluation of validation success showed that the tip position was "optimal" in 79 cases (71.8%) and "suboptimal" in 26 cases (23.6%) in the clinical setting. There were no venous thromboses or catheter occlusions during the catheter placements.

Conclusion: This Formula could be acceptable in performing the bedside PICC placement in the real clinical settings.

Background: Signal-to-noise ratio (SNR) is a key metric for evaluating MRI image quality, but conventional measurement methods are time-consuming and operator-dependent. Deep learning offers potential for automating this process.

Purpose: To develop and validate a deep learning-based method for automatic SNR measurement from single MRI images.

Material and methods: A Pix2Pix framework with a U-Net++ generator and GAN-based discriminator was trained using axial brain MRI images (T1WI, T2WI, and FLAIR) from a 3T scanner. The model generated signal and noise maps from a single image, and SNR maps were computed by pixel-wise division. Whole-brain, white matter (WM), and cerebrospinal fluid (CSF) regions were automatically segmented for regional SNR measurement. The subtraction-map method served as the reference. Structural similarity index (SSIM), correlation coefficients, and Bland-Altman analyses were used to evaluate agreement.

Results: Across all sequences, the mean SSIM was 0.95 ± 0.02. SNR values showed strong correlations with the reference method (r > 0.86) and low relative errors (<7%) for whole-brain, WM, and CSF. Bland-Altman analysis demonstrated a small paired bias and narrow 95% limits of agreement across sequences.

Conclusion: The proposed deep learning method enables automatic, accurate, and observer-independent SNR quantification from single MR images, supporting clinical and research image quality evaluation.

Although a routine and generally safe procedure, central venous catheter insertion has inherent risks, which can be mitigated with the use of imaging studies. This case report describes the unrecognized intrathoracic placement of a central venous catheter in a 15-year-old female with a history of anorexia nervosa. A chest radiograph obtained immediately after the procedure appeared normal at the time, but retrospective review revealed a subtle right-sided pneumothorax. Subsequent computed tomography demonstrated that the catheter had perforated the right internal jugular vein and entered the thoracic cavity. The case highlights the limitations of relying solely on chest radiography for central venous catheter placement confirmation, the potential for missed subtle complications, and emphasizes the importance of clinical vigilance and additional imaging when catheter malposition is suspected.

Background: Right iliac fossa (RIF) pain is a frequent and challenging presenting complaint in emergency departments, encompassing a wide spectrum of acute and chronic conditions.

Purpose: To compare effectiveness of ultrasound versus initial clinical and lab tests for diagnosing acute appendicitis in patients with RIF pain, while also evaluating the impact of ultrasound operator experience as well as portable ultrasound system.

Materials and methods: This retrospective study included 525 patients (aged ≥15 years) presenting with acute RIF pain to three emergency departments in Thi-Qar Governorate, Iraq (January 2024-January 2025). Sensitivity, specificity, predictive values (PPV and NPV), and accuracy for diagnosing acute appendicitis were calculated. Multivariable logistic regression identified independent predictors of diagnostic accuracy for both modalities.

Results: Among 525 patients, appendicitis was the final diagnosis in 273 (52.00%). For diagnosing acute appendicitis, ultrasound demonstrated significantly higher sensitivity (89.7% vs 67.4%), specificity (67.1% vs 46.4%), and overall accuracy (78.9% vs 57.3%) compared to clinical-laboratory assessment. Independent predictors of higher ultrasound accuracy included US operator experience (Senior EM Physician vs. Resident: aOR 3.15, 95% CI: 1.80-5.52) and presence of rebound tenderness (aOR 2.40, 95% CI: 1.35-4.27). For clinical-laboratory assessment, ED physician experience (Senior vs. Resident: aOR 1.48, 95% CI: 1.15-2.41) was one of the independent predictors of higher accuracy.

Conclusion: Ultrasound significantly outperforms initial clinical-laboratory assessment in diagnosing acute appendicitis among patients with RIF pain in this setting. US operator experience is a key determinant of ultrasound accuracy. Our findings support the effective use of portable ultrasound systems in the emergency setting.

Background: Lumbar disc degeneration (LDD) is frequently evaluated using the Pfirrmann classification. While this composite grading system provides an overview of degeneration severity, it may oversimplify LDD by overlooking variability in individual disc components, reducing its effectiveness in longitudinal studies and constraining its applicability in artificial intelligence-based image analysis.

Purpose: To examine the 14-year progression of LDD using the Pfirrmann classification and its individual components, and to evaluate the potential of component-based analysis.

Material and methods: LDD was assessed using MRI in 19 males (95 discs) at ages 37 and 51 by two radiologists. Evaluations included Pfirrmann grading, quantitative nucleus pulposus (NP) signal intensity, and visual grading of NP inhomogeneity, annulus fibrosus (AF) border distinction, and disc height (DH). Analyses included longitudinal changes in LDD variables and correlations between Pfirrmann grading and disc components. To assess overall LDD, a summary score was calculated by summing individual disc grades.

Results: Pfirrmann grading correlated strongly with AF border distinction, moderately with NP signal intensity, and weakly with NP inhomogeneity and DH. Pfirrmann summary score (range 5-25) increased by 3 points over time. Variability was observed in the progression of individual disc component degeneration. While mean NP signal intensity significantly decreased, some discs exhibited increase.

Conclusion: This longitudinal study highlights complexity of LDD and variability in disc component changes. While Pfirrmann classification captures overall degeneration, its limitations in detecting subtle variations in disc components suggest a need for more detailed assessments to enhance diagnostic precision and support the development of automated analysis tools.

Dropped head syndrome, characterized by excessive flexion of the neck, frequently leads to significant impairment in quality of life. Among the various causes of this syndrome, some cases respond effectively to internal medicine. We report a case of a woman in her 70s who presented with dropped head syndrome and was finally diagnosed with hypothyroid myopathy limited to the extensor muscles of the neck. Cervical spine MRI at the initial examination indicated thyroid atrophy, increased subcutaneous fat, and a mild high signal in the right cervical extensor muscles on fat-suppressed T2-weighted images. Blood tests confirmed hypothyroidism. Treatment with levothyroxine improved the symptoms and normalized the blood test results. This case highlights the importance of careful evaluation of the thyroid gland and paravertebral muscles in cervical spine MRI. They can offer diagnostic clues for underlying the important causative role of thyroid disease in dropped head syndrome.

Teratomas are a common type of germ cell tumours which may be benign or malignant. Benign mature teratomas are the most frequent subtype and typically show intralesional fat and calcifications within a cystic mass. Immature/malignant teratomas are usually larger with irregular solid components, coarse calcifications, small amounts of fat, and with or without necrosis or haemorrhage. Teratomas can manifest in various anatomical locations, particularly in the sacrococcygeal, gonadal, mediastinal, retroperitoneal, and intracranial regions. This article explores the imaging characteristics and diverse locations of teratomas as well as discusses about possible differential diagnoses to facilitate early detection and ensure prompt treatment.

Background: Abdominal bulging affects up to one-fourth of patients after flank incision, with half experiencing impaired quality of life. Identifying patients at risk for morbid bulge could improve preventive and supportive care.

Purpose: To characterise muscular changes related to postoperative abdominal bulging and design a visual scoring system to grade bulge on postoperative CT scans.

Material and methods: Patients treated with open partial nephrectomy via a flank incision between 2005 and 2016 at the University Hospital of Umeå were included. Pre- and postoperative CT scans of the first 50 consecutive patients were used to characterise imaging features of the postoperative abdominal wall. From these features, a four-tiered scoring system for abdominal bulge was designed. Two independent observers tested the system on CT scans from the 50 next patients. Inter-rater reliability was assessed using Fleiss' Kappa.

Results: Common features of abdominal bulging were extracted and a four-tier visual score ranging from normal abdominal wall to severe bulge was developed. Among the patients, ∼70% had a normal abdominal wall, ∼25% had bulge score 1, ∼7% score 2, and ∼1% score 3. Inter-rater agreement was 73.5%, with Fleiss' Kappa 0.44.

Conclusion: Features of bulge were reduced muscle thickness and ipsilateral gravitational slump affecting part or all of the lateral abdominal wall. The proposed scoring system demonstrated only moderate inter-rater reliability in this pilot setting. Further research on postoperative abdominal wall changes is needed before implementing imaging-based assessments in clinical care.

Background: Management of rectal cancer requires accurate staging and treatment. Neoadjuvant chemoradiotherapy offers tumour size reduction and mitigation of the risk of local relapse. Patients with complete response to neoadjuvant treatment can be enclosed in watchful waiting (WW). Recent studies have explored magnetic resonance imaging (MRI) T1 relaxation time (T1RT) as a predictive biomarker for treatment response in rectal cancer. Preliminary findings indicate that lower T1RT correlates with pathologic complete response. However, inclusion of patients in WW remains unexplored.

Purpose: This prospective study aims to investigate T1RT 6 weeks after neoadjuvant treatment and the ability to determine complete response.

Material and methods: MRI scans are conducted on a 1.5 T MRI-unit. T1RT is measured at time of diagnosis and 6 weeks after neoadjuvant treatment. Experienced radiologists analyse T1RT using specialised software. Treatment decisions are made in multidisciplinary team conferences based on tumour staging. Endpoints include tumour visibility on MRI and endoscopy, along with histopathological analysis of surgical specimens. Statistical methods include t test and receiver operating characteristic curves. Sample size calculations showed we must enrol 76 participants to achieve a statistical power of 80% with an α = 0.05.

Results: Data analysis begins in winter 2025. Results are planned to be submitted in spring 2026.

Conclusion: The implications of this study extend to the potential refinement of treatment strategies, offering patients the prospect of improved outcomes and the potential avoidance of surgery-associated risks. We expect to find a lower relaxation time in fibrotic tissue compared to non-responsive cancerous tissue after 6 weeks.

Cholecystitis is a common disease, but the occurrence of gallbladder strangulation is extremely rare. Here, we report a case of an 88-year-old woman with strangulated cholecystitis caused by an intraperitoneal band. Computed tomography (CT) scan revealed a constriction of the gallbladder body and marked wall thickening at the fundus. Additionally, the finding suggested torsion at the constricted area, which we diagnosed as gallbladder torsion. Cholecystectomy was performed immediately, and the diagnosis was strangulated cholecystitis caused by a band. The imaging findings of strangulated cholecystitis are similar to gallbladder torsion, making it difficult to diagnose preoperatively. We will discuss the imaging findings of strangulated cholecystitis and gallbladder torsion.