Accuracy of magnetic resonance imaging for measuring maturing cartilage: A phantom study

OBJECTIVES: To evaluate the accuracy of magnetic resonance imaging measurements of cartilage tissue-mimicking phantoms and to determine a combination of magnetic resonance imaging parameters to optimize accuracy while minimizing scan time. METHOD: Edge dimensions from 4 rectangular agar phantoms ranging from 10.5 to 14.5 mm in length and 1.25 to 5.5 mm in width were independently measured by two readers using a steel ruler. Coronal T1 spin echo (T1 SE), fast spoiled gradient-recalled echo (FSPGR) and multiplanar gradient-recalled echo (GRE MPGR) sequences were used to obtain phantom images on a 1.5-T scanner. RESULTS: Inter- and intra-reader reliability were high for both direct measurements and for magnetic resonance imaging measurements of phantoms. Statistically significant differences were noted between the mean direct measurements and the mean magnetic resonance imaging measurements for phantom 1 when using a GRE MPGR sequence (512x512 pixels, 1.5-mm slice thickness, 5:49 min scan time), while borderline differences were noted for T1 SE sequences with the following parameters: 320x320 pixels, 1.5-mm slice thickness, 6:11 min scan time; 320x320 pixels, 4-mm slice thickness, 6:11 min scan time; and 512x512 pixels, 1.5-mm slice thickness, 9:48 min scan time. Borderline differences were also noted when using a FSPGR sequence with 512x512 pixels, a 1.5-mm slice thickness and a 3:36 min scan time. CONCLUSIONS: FSPGR sequences, regardless of the magnetic resonance imaging parameter combination used, provided accurate measurements. The GRE MPGR sequence using 512x512 pixels, a 1.5-mm slice thickness and a 5:49 min scan time and, to a lesser degree, all tested T1 SE sequences produced suboptimal accuracy when measuring the widest phantom

Clinical Impact of Chronic Venous Changes Induced by Central Lines in Children: A Cohort with Abnormal Venograms

PURPOSE To explore the hypothesis that central venous stenosis/obstructions (CVS/O) in children are influenced by prior central venous access devices (CVADs) and are associated with future risk for thromboses. MATERIAL AND METHODS A convenience sample of 100 patients with abnormal venography (stenosis, collaterals, occlusions) documented during peripherally inserted central catheter (PICC) placements were identified from consecutive PICC placements (January 2008 to November 2012). The patients (41 males, 59 females, median age 2.7 years, median weight 11 kg) were categorized based on venographic presence (Group A, n = 53) or absence (Group B, n = 47) of visible connection to the superior vena cava. Each patient's CVAD history, before and after venography, was analyzed (until October 2016). RESULTS Before venogram, Group B patients were associated with a higher number of previous CVADs, larger diameter devices, greater incidence of malposition, and more use of polyurethane catheters than Group A patients (P < .001). An ipsilateral PICC was successfully placed in 98% of Group A, compared to 32% of Group B (P < .001). After venogram, significantly more Doppler ultrasounds (DUS) were performed and thromboses diagnosed in Group B (57% and 36%) compared to Group A (21% and 8%) (P < .003; P = .001), respectively. CONCLUSIONS Previous catheter characteristics influenced the severity of venographic changes of CVS/O (Group B). Group B was associated with more subsequent symptomatic thromboses. This information may assist parents and referring physicians to anticipate potential adverse sequelae from CVS/O on the child's venous health

Analyzing Barriers and Enablers for the Acceptance of Artificial Intelligence Innovations into Radiology Practice: A Scoping Review

Objectives: This scoping review was conducted to determine the barriers and enablers associated with the acceptance of artificial intelligence/machine learning (AI/ML)-enabled innovations into radiology practice from a physician’s perspective. Methods: A systematic search was performed using Ovid Medline and Embase. Keywords were used to generate refined queries with the inclusion of computer-aided diagnosis, artificial intelligence, and barriers and enablers. Three reviewers assessed the articles, with a fourth reviewer used for disagreements. The risk of bias was mitigated by including both quantitative and qualitative studies. Results: An electronic search from January 2000 to 2023 identified 513 studies. Twelve articles were found to fulfill the inclusion criteria: qualitative studies (n = 4), survey studies (n = 7), and randomized controlled trials (RCT) (n = 1). Among the most common barriers to AI implementation into radiology practice were radiologists’ lack of acceptance and trust in AI innovations; a lack of awareness, knowledge, and familiarity with the technology; and perceived threat to the professional autonomy of radiologists. The most important identified AI implementation enablers were high expectations of AI’s potential added value; the potential to decrease errors in diagnosis; the potential to increase efficiency when reaching a diagnosis; and the potential to improve the quality of patient care. Conclusions: This scoping review found that few studies have been designed specifically to identify barriers and enablers to the acceptance of AI in radiology practice. The majority of studies have assessed the perception of AI replacing radiologists, rather than other barriers or enablers in the adoption of AI. To comprehensively evaluate the potential advantages and disadvantages of integrating AI innovations into radiology practice, gathering more robust research evidence on stakeholder perspectives and attitudes is essential

Increased risk of symptomatic upper-extremity venous thrombosis with multiple peripherally inserted central catheter insertions in pediatric patients

BACKGROUND Peripherally inserted central catheters (PICCs) are associated with superficial and deep venous thrombosis of the arm. OBJECTIVE The purpose of this study was to analyze the sequelae of repeated upper limb PICC insertions in children, in terms of the frequency of upper limb thrombosis in this patient group. MATERIALS AND METHODS The study population included all children who underwent their first successful arm PICC insertion between January 2010 and December 2015. We included subsequent ipsilateral arm PICCs in the analysis. Patients were followed until March 2016 or until any alternative central venous line insertion. For each PICC insertion, we collected demographic variables and line characteristics. We correlated all symptomatic deep and superficial thromboses of the arm with the PICC database. RESULTS Applying inclusion and exclusion criteria, 2,180 PICCs remained for analysis. We identified first, second, third and fourth PICC insertions in the same arm in 1,955, 181, 38 and 6 patients, respectively. In total there were 57 upper body deep symptomatic thrombotic events. An increasing odds ratio was seen with higher numbers of PICC insertions, which was significant when comparing the first with the third and fourth PICC insertions in the same arm (odds ratio [OR] 6.00, 95% confidence interval [CI] 2.25-16.04, P=0.0004). Double-lumen PICCs were associated with a significantly higher risk of thrombosis than single lumen (OR 2.77, 95% CI 1.72-4.47, P=0.0003). CONCLUSION Repetitive PICC insertions in the same arm are associated with an increased risk of symptomatic thrombosis. Double-lumen PICCs are associated with a higher risk of thrombosis compared to single-lumen lines

Accuracy of magnetic resonance imaging for measuring maturing cartilage: A phantom study

OBJECTIVES: To evaluate the accuracy of magnetic resonance imaging measurements of cartilage tissue-mimicking phantoms and to determine a combination of magnetic resonance imaging parameters to optimize accuracy while minimizing scan time. METHOD: Edge dimensions from 4 rectangular agar phantoms ranging from 10.5 to 14.5 mm in length and 1.25 to 5.5 mm in width were independently measured by two readers using a steel ruler. Coronal T1 spin echo (T1 SE), fast spoiled gradient-recalled echo (FSPGR) and multiplanar gradient-recalled echo (GRE MPGR) sequences were used to obtain phantom images on a 1.5-T scanner. RESULTS: Inter- and intra-reader reliability were high for both direct measurements and for magnetic resonance imaging measurements of phantoms. Statistically significant differences were noted between the mean direct measurements and the mean magnetic resonance imaging measurements for phantom 1 when using a GRE MPGR sequence (512x512 pixels, 1.5-mm slice thickness, 5:49 min scan time), while borderline differences were noted for T1 SE sequences with the following parameters: 320x320 pixels, 1.5-mm slice thickness, 6:11 min scan time; 320x320 pixels, 4-mm slice thickness, 6:11 min scan time; and 512x512 pixels, 1.5-mm slice thickness, 9:48 min scan time. Borderline differences were also noted when using a FSPGR sequence with 512x512 pixels, a 1.5-mm slice thickness and a 3:36 min scan time. CONCLUSIONS: FSPGR sequences, regardless of the magnetic resonance imaging parameter combination used, provided accurate measurements. The GRE MPGR sequence using 512x512 pixels, a 1.5-mm slice thickness and a 5:49 min scan time and, to a lesser degree, all tested T1 SE sequences produced suboptimal accuracy when measuring the widest phantom

MRI thresholds for discrimination between normal and mild temporomandibular joint involvement in juvenile idiopathic arthritis

Abstract Background Currently there is no consensus agreement on the degree of enhancement in normal temporomandibular joints (TMJ) in children, which makes it difficult for clinicians to distinguish between the presence/absence of mild synovitis. Quantitative measurements of synovial and condylar enhancement may be useful additions to current qualitative methods on early MRI diagnosis and follow up of TMJ involvement in JIA. The purpose of the study is to establish thresholds/tendencies for quantitative measures that enable distinction between mild TMJ involvement and normal TMJ appearance based on the degree of synovial and bone marrow enhancement in JIA patients. Methods TMJ MRI examinations in 67 children with JIA and in 24 non-rheumatologic children who underwent MRI for neurologic/orbit indications were retrospectively assessed. As a priori determined TMJs of JIA patients were categorized into three groups by experienced staff radiologists based on the degree of synovial and condylar enhancement: no active disease (rheumatologic control), mild and moderate/severe findings. The signal intensity (SI) of the synovial tissue around each condyle and of the bone marrow was measured to calculate the enhancement ratio (ER) and relative SI change. The ER was calculated using signal to noise ratios, while relative SI change was calculated using signal intensities alone. Quantitative measurements of synovial and condylar enhancement of TMJs with mild or moderate/severe findings were compared with the rheumatologic and non-rheumatologic controls. Results Mean ER values were significantly different between the TMJs without active disease and those with mild and moderate/severe synovial enhancement, with highest values in the moderate/severe group (P  0.10). 27/60 (45 %) TMJs without active disease had osteochondral changes. 8/40 (20 %) TMJs in the mild group did not demonstrate any synovial thickening. Conclusions Quantitative signal to noise ratios of TMJ synovial and condylar enhancement generate thresholds/tendencies, which offer additional information to differentiate mild synovitis from normal TMJs in JIA patients. Osteochondral changes and synovial thickening may not be reliable indicators of active TMJ involvement and should be differentiated from synovial enhancement

Usefulness of TI-scout images in the assessment of late gadolinium enhancement in children

Abstract Background Cardiovascular magnetic resonance (CMR) late gadolinium enhancement (LGE) requires identification of the normal myocardial nulling time using inversion time (TI)-scout imaging sequence. Although TI-scout images are not primarily used for myocardial assessment, they provide information regarding different signal recovery patterns of normal and abnormal myocardium facilitating identification of LGE in instances where standard LGE images alone are not diagnostic. We aimed to assess the diagnostic performance of TI-scout as compared to that of standard LGE images. Methods CMR studies with LGE imaging in 519 patients (345 males, 1–17 years) were reviewed to assess the diagnostic performance of LGE imaging in terms of the location of LGE and the pathologic entities. The diagnostic performance of the TI-scout and standard LGE imaging was classified into four categories: (1) equally diagnostic, (2) TI-scout superior to standard LGE, (3) standard LGE superior to TI-scout, and (4) complementary, by the consensus of the two observers. Results The study cohort consisted of 440 patients with negative LGE and 79 with evidence for LGE. For a negative diagnosis of LGE, TI-scout and standard LGE images were equally diagnostic in 75% of the cases and were complementary in 12%. For patients with LGE, TI-scout images were superior to standard LGE images in 52% of the cases and were complementary in 19%. The diagnostic performance of TI-scout images was superior to that of standard LGE images in all locations. TI-scout images were superior to standard LGE images in 11 of 12 (92%) cases with LGE involving the papillary muscles, in 7 /12 (58%) cases with subendocardial LGE, and in 4/7 (57%) cases with transmural LGE. TI-scout images were particularly useful assessing the presence and extent of LGE in hypertrophic cardiomyopathy (HCM). TI-scout was superior to standard LGE in 6/10 (60%) and was complementary in 3/10 (30%) of the positive cases with HCM. Conclusions TI-scout images enhance the diagnostic performance of LGE imaging in children

Radiomic Features Based on MRI Predict Progression-Free Survival in Pediatric Diffuse Midline Glioma/Diffuse Intrinsic Pontine Glioma

Purpose: Biopsy-based assessment of H3 K27 M status helps in predicting survival, but biopsy is usually limited to unusual presentations and clinical trials. We aimed to evaluate whether radiomics can serve as prognostic marker to stratify diffuse intrinsic pontine glioma (DIPG) subsets. Methods: In this retrospective study, diagnostic brain MRIs of children with DIPG were analyzed. Radiomic features were extracted from tumor segmentations and data were split into training/testing sets (80:20). A conditional survival forest model was applied to predict progression-free survival (PFS) using training data. The trained model was validated on the test data, and concordances were calculated for PFS. Experiments were repeated 100 times using randomized versions of the respective percentage of the training/test data. Results: A total of 89 patients were identified (48 females, 53.9%). Median age at time of diagnosis was 6.64 years (range: 1–16.9 years) and median PFS was 8 months (range: 1–84 months). Molecular data were available for 26 patients (29.2%) (1 wild type, 3 K27M-H3.1, 22 K27M-H3.3). Radiomic features of FLAIR and nonenhanced T1-weighted sequences were predictive of PFS. The best FLAIR radiomics model yielded a concordance of .87 [95% CI: .86–.88] at 4 months PFS. The best T1-weighted radiomics model yielded a concordance of .82 [95% CI: .8–.84] at 4 months PFS. The best combined FLAIR + T1-weighted radiomics model yielded a concordance of .74 [95% CI: .71–.77] at 3 months PFS. The predominant predictive radiomic feature matrix was gray-level size-zone. Conclusion: MRI-based radiomics may predict progression-free survival in pediatric diffuse midline glioma/diffuse intrinsic pontine glioma

Findings in percutaneous trans-hepatic cholecysto-cholangiography in neonates and infants presenting with conjugated hyperbilirubinemia: emphasis on differential diagnosis and cholangiographic patterns

Abstract Background Biliary atresia (BA) is one of the causes of conjugated hyperbilirubinemia in infants which if untreated leads to end-stage liver disease and death. Percutaneous Trans-hepatic Cholecysto-Cholangiography (PTCC) is a minimally invasive study which can be utilized in the diagnostic work-up of these patients. This study’s purpose is to describe the experience with PTCC in neonates, the imaging findings encountered, and the abnormal patterns which warrant further investigation. Methods A 16-year single-center retrospective study of patients with persistent neonatal cholestasis (suspected BA) undergoing PTCC. Patient demographics, laboratory values, PTCC images, pathology and surgical reports were reviewed. Results 73 patients underwent PTCC (68% male, mean age 8.7 weeks, mean weight 4.0 Kg). The majority of studies were normal (55%). Abnormal patterns were identified in 33 cases, 79% were diagnosed with BA and 12% with Alagille syndrome. Non-opacification of the common hepatic duct with a narrowed common bile duct (42%) and isolated small gallbladder (38%) were the most common patterns in BA. Conclusion PTCC is a minimally invasive study in the diagnostic work-up of infants presenting with conjugated hyperbilirubinemia (suspected BA). Further invasive investigations or surgery can be avoided when results are normal