RASopathies for Radiologists Handa, Atsuhiko; Tsujioka, Yuko; Nishimura, Gen ...
Radiographics
44, Številka:
5
Journal Article
Recenzirano
RASopathies are a heterogeneous group of genetic syndromes caused by germline mutations in a group of genes that encode components or regulators of the Ras/mitogen-activated protein kinase (MAPK) ...signaling pathway. RASopathies include neurofibromatosis type 1, Legius syndrome, Noonan syndrome, Costello syndrome, cardiofaciocutaneous syndrome, central conducting lymphatic anomaly, and capillary malformation-arteriovenous malformation syndrome. These disorders are grouped together as RASopathies based on our current understanding of the Ras/MAPK pathway. Abnormal activation of the Ras/MAPK pathway plays a major role in development of RASopathies. The individual disorders of RASopathies are rare, but collectively they are the most common genetic condition (one in 1000 newborns). Activation or dysregulation of the common Ras/MAPK pathway gives rise to overlapping clinical features of RASopathies, involving the cardiovascular, lymphatic, musculoskeletal, cutaneous, and central nervous systems. At the same time, there is much phenotypic variability in this group of disorders. Benign and malignant tumors are associated with certain disorders. Recently, many institutions have established multidisciplinary RASopathy clinics to address unique therapeutic challenges for patients with RASopathies. Medications developed for Ras/MAPK pathway-related cancer treatment may also control the clinical symptoms due to an abnormal Ras/MAPK pathway in RASopathies. Therefore, radiologists need to be aware of the concept of RASopathies to participate in multidisciplinary care. As with the clinical manifestations, imaging features of RASopathies are overlapping and at the same time diverse. As an introduction to the concept of RASopathies, the authors present major representative RASopathies, with emphasis on their imaging similarities and differences.
RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.
Costochondral junction (CCJ) rib fractures pose a challenge in the radiographic detection and dating of infant abuse.
The purpose of this article was to assess the temporal pattern of radio-graphic ...findings of CCJ fractures on a serial skeletal survey (SS).
Reports of SSs performed for suspected infant abuse were reviewed to identify those reporting a CCJ fracture. Study inclusion required undergoing initial and approximately 2-week follow-up SSs that included anteroposterior and bilateral oblique radiographs of the reported CCJ rib fracture. Two pediatric radiologists retrospectively classified fractures in terms of the primary injury pattern (bucket-handle: visible crescentic fracture line; corner: visible triangular fracture line; other) and secondary healing pattern (growth disturbance; sclerosis; subperiosteal new bone formation SPNBF). Discrepant readings were resolved by consensus.
The final cohort included 26 infants with 81 CCJ fractures. On initial SS, 59% (48/81) of fractures showed a primary pattern, most commonly a bucket-handle pattern (46%; 37/81); 6% (5/81) showed a primary pattern on follow-up SS (
< .001). On initial SS, the prevalence of a secondary pattern was 89% (72/81), most commonly a growth disturbance (85%; 69/81), followed by sclerosis (57%; 46/81); 80% (65/81) showed a secondary pattern on follow-up SS (
= .12). Overall prevalence of SPNBF was 28% (23/81). Addition of bilateral oblique views on initial SS resulted in a significant increase relative to the anteroposterior views alone in the detection of primary and secondary patterns by 15% (
= .04) and 30% (
< .001), respectively.
A bucket-handle appearance is the most common primary pattern of fracture. The significantly lower prevalence of a primary pattern on follow-up vs initial SSs suggests that the CCJ fracture line is usually visible for only approximately 2 weeks. A growth disturbance of the rib end is the most common secondary pattern, followed by bony sclerosis, consistent with a healing injury. SPNBF is uncommon. Most CCJ fractures are in a healing phase at initial diagnosis. The signs of repair commonly remain visible on 2-week follow-up. The increased diagnostic yield of oblique views provides support to the inclusion of these projections in routine SS protocols.
The findings will help radiologists improve the diagnosis and dating of CCJ rib fractures.
Abstract Introduction Blunt abdominal trauma is a common problem in children. Computed tomography (CT) is the gold standard for imaging in pediatric blunt abdominal trauma, however up to 50% of CTs ...are normal and CT carries a risk of radiation-induced cancer. Contrast enhanced ultrasound (CEUS) may allow accurate detection of abdominal organ injuries while eliminating exposure to ionizing radiation. Methods Children aged 7–18 years with a CT-diagnosed abdominal solid organ injury underwent grayscale/power Doppler ultrasound (conventional US) and CEUS within 48 h of injury. Two blinded radiologists underwent a brief training in CEUS and then interpreted the CEUS images without patient interaction. Conventional US and CEUS images were compared to CT for the presence of injury and, if present, the injury grade. Patients were monitored for contrast-related adverse reactions. Results Twenty one injured organs were identified by CT in eighteen children. Conventional US identified the injuries with a sensitivity of 45.2%, which increased to 85.7% using CEUS. The specificity of conventional US was 96.4% and increased to 98.6% using CEUS. The positive predictive value increased from 79.2% to 94.7% and the negative predictive value from 85.3% to 95.8%. Two patients had injuries that were missed by both radiologists on CEUS. In a 100 kg, 17 year old female, a grade III liver injury was not seen by either radiologist on CEUS. Her accompanying grade I kidney injury was not seen by one of the radiologist on CEUS. The second patient, a 16 year old female, had a grade III splenic injury that was missed by both radiologists on CEUS. She also had an adjacent grade II kidney injury that was seen by both. Injuries, when noted, were graded within 1 grade of CT 33/35 times with CEUS. There were no adverse reactions to the contrast. Conclusion CEUS is a promising imaging modality that can detect most abdominal solid organ injuries in children while eliminating exposure to ionizing radiation. A multicenter trial is warranted before widespread use can be recommended. Level of evidence Level II; Diagnostic Prospective Study.
Diagnostic imaging of the pediatric stomach often provides a challenge for practicing radiologists. Radiologists should be aware of relatively unusual congenital pathology, especially when imaging ...very young children with gastrointestinal symptoms. We review congenital pathology of the pediatric stomach.
Abstract Magnetic resonance imaging (MRI) could potentially be used to non-invasively predict the strength of an ACL graft after ACL reconstruction. We hypothesized that the volume and T2 relaxation ...parameters of the ACL graft measured with MRI will predict the graft structural properties and anteroposterior (AP) laxity of the reconstructed knee. Nine goats underwent ACL reconstruction using a patellar tendon autograft augmented with a collagen or collagen–platelet composite. After 6 weeks of healing, the animals were euthanized, and the reconstructed knees were retrieved and imaged on a 3T scanner. AP laxity was measured prior to dissecting out the femur–graft–tibia constructs which were then tested to tensile failure to determine the structural properties. Regression analysis indicated a statistically significant relationship between the graft volume and the failure load ( r2 =0.502; p =0.049). When graft volume was normalized to the T2 relaxation time, the relationship was even greater ( r2 =0.687; p =0.011). There was a significant correlation between the graft volume and the linear stiffness ( r2 =0.847; p <0.001), which remained significant with T2 normalization ( r2 =0.764; p =0.002). For AP laxity at 30° flexion, there was not a significant correlation with graft volume, but there was a significant correlation with volume normalized by the T2 relaxation time ( r2 =0.512; p =0.046). These results suggest that MRI volumetric measures combined with graft T2 properties may be useful in predicting the structural properties of ACL grafts.
Diagnostic imaging of pediatric gastric masses often provides a challenge for the practicing radiologist. Radiologists should be aware of this relatively unusual pathology, particularly in ...cross-sectional imaging findings. We will review pediatric gastric masses and mass-like lesions, focusing on neoplastic and inflammatory etiologies.
Although advances have been made in the prenatal diagnosis of esophageal atresia (EA), most neonates are not identified until after birth. The distended hypopharynx (DHP) has been suggested as a ...novel prenatal sign for EA. We assess its diagnostic accuracy and predictive value on ultrasound (US) and magnetic resonance imaging (MRI), both alone and in combination with the esophageal pouch (EP) and secondary signs of EA (polyhydramnios and a small or absent fetal stomach).
We retrospectively reviewed fetal US and MRI reports and medical records of 88 pregnant women evaluated for possible EA from 2000 to 2016. Seventy-five had postnatal follow-up that confirmed or disproved the diagnosis of EA and were included in our analysis.
Seventy-five women had 107 study visits (range 1–4). DHP and/or EP were seen on US and/or MRI in 36% of patients, and 78% of those patients had EA. DHP was 24% more sensitive for EA than EP, while EP was 30% more specific. After 28weeks of gestation, DHP had a predictive accuracy for EA of 0.929 (P=0.001).
DHP is a sensitive additional prenatal sign of EA. More accurate diagnosis of EA allows for improved counseling regarding delivery, postnatal evaluation, and surgical correction.
Diagnostic.
Level II.
To retrospectively analyze magnetic resonance (MR) arthrographic findings in patients with clinical cam-type femoroacetabular impingement.
This study was approved by the institutional review board, ...and informed consent was waived. Study was compliant with the Health Insurance Portability and Accountability Act. Forty-two MR arthrograms obtained in 40 patients with clinical femoroacetabular impingement were analyzed retrospectively by two radiologists. Quantitative analysis by using alpha angle measurement was performed to assess anterosuperior femoral head-neck morphology. Presence of labral tears, articular cartilage lesions, paralabral cysts, os acetabuli, and synovial herniation pits was recorded. Presence of the typical triad of anterosuperior labral tear, anterosuperior cartilage lesion, and abnormal alpha angle was recorded. Surgical comparison was available for 11 patients.
At imaging, in 40 patients (22 male, 18 female) with a mean age of 36.5 years, 39 of 42 hips (93%) had an abnormal alpha angle, with a mean angle of 69.7 degrees ; 40 of 42 (95%) had an anterosuperior cartilage abnormality; and 42 of 42 (100%) had an anterosuperior labral tear. Thirty-seven of 42 hips (88%) had the triad. Six had paralabral cysts, 17 had an os acetabuli, and two had synovial herniation pits. Surgical comparison for 11 hips led to confirmation of all labral and cartilage abnormalities seen at imaging.
MR arthrography demonstrated a triad of abnormal head-neck morphology, anterosuperior cartilage abnormality, and anterosuperior labral abnormality in 37 of 42 patients with cam-type femoroacetabular impingement.
Splenic masses present a diagnostic challenge to radiologists and clinicians alike, with a relative paucity of data correlating radiologic findings to pathological diagnosis in the pediatric ...population. To illustrate splenic mass imaging findings and approximate lesion prevalence, we retrospectively reviewed all splenectomies and splenic biopsies for splenic masses at a single academic pediatric hospital over a 10-year period in patients 18 years and younger. A total of 31 splenic masses were analyzed. Lesion prevalence, pathology and imaging features associated with sampled splenic masses are described. The lesions encountered include benign splenic cysts (9), vascular anomalies (7), hamartoma (3), leukemia/lymphoma (3), granulomata (3) and metastasis (2). We also identified single cases of angiosarcoma, splenic cord capillary hemangioma, congestive hemorrhage, and benign smooth muscle neoplasm.
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