MR imaging features of cuboid fractures in children.

BACKGROUND: Cuboid fractures are rare, usually occult on initial radiographs and are often underdiagnosed. MRI is more sensitive than radiographs for detecting acute, non-displaced cuboid fractures in adults, but only case reports have described these findings in children. OBJECTIVE: To summarize the MR and clinical features of cuboid fractures and compare MR findings with initial and follow-up radiographs in a cohort of children. MATERIALS AND METHODS: A retrospective search for patients <18 years of age with cuboid fractures was performed during a 10-year period at a large tertiary children's hospital. Subjects with cuboid fractures reported on MRI and available clinical history were included. MR images were evaluated for fracture location, fracture morphology, percentage of marrow edema in the cuboid, subchondral disruption, and associated tendon or ligamentous injury. Initial and short-term follow-up radiographs were also reviewed when available. RESULTS: Nineteen children ages 18 months to 17 years (mean: 9.0 years, standard deviation: 4.1 years, 63% boys) were diagnosed with cuboid fractures by MRI. Most cases of cuboid fractures are related to acute trauma (63%) but can be seen as stress fractures (16%). Most fractures (17/19, 89%) were linear in configuration. Fractures were most commonly adjacent to the tarsometatarsal joint (10/19, 52%). The degree of marrow edema was variable. Ligamentous injury was seen in two patients and tendon pathology was seen in one, all adolescents. Initial radiographs (n=10) were negative in 9 cases (90%). All available follow-up radiographs (n=12, obtained 19-42 days after MRI) demonstrated sclerosis in the region of the fracture. CONCLUSION: MR-depicted cuboid fractures in children typically occur in isolation. The fractures were most commonly adjacent to the tarsometatarsal joint and linear in morphology. Initial radiographs were usually normal and follow-up radiographs depicted sclerosis at the site of fracture in all available cases.

Emergent Endovascular Treatment of Penetrating Trauma: Solid Organ and Extremity.

Penetrating injuries can result in acute or subacute arterial injuries of the solid organs or extremities. Although most penetrating injuries are managed conservatively, some patients require endovascular or surgical treatment. Often, the best method for management is controversial and the level of urgency for clinical decision-making is high. Once the decision has been made to intervene, the operator must also determine the best embolization material and technique to use. Not unfrequently, these decisions are made during the course of the procedure. There are numerous embolization agents, each of which serves a very specific purpose, depending on the clinical scenario. Within this article, we will review endovascular treatment indications, contraindications, and endovascular techniques for the treatment of penetrating trauma of the solid organs or extremities.

CT Radiation Dose Reduction in Robot-assisted Pediatric Spinal Surgery.

STUDY DESIGN: Retrospective consecutive cohort series. OBJECTIVE: The aim of this study was to develop a low-dose computed tomography (CT) protocol for use in robot-assisted pediatric spinal surgery. SUMMARY OF BACKGROUND DATA: CT scans are utilized preoperatively for preoperative planning, by navigation software during robot-assisted surgery, and postoperatively to assess surgical implant placement. Traditionally high radiation doses produced by CT scanning are a concern in the highly radiosensitive pediatric population. METHODS: We developed a low-dose protocol using phantom scans. A cohort of patients undergoing CT scanning using the low-dose protocol was collected. Further, a matching cohort of patients who underwent standard scanning was collected. Image quality was assessed by observer ratings. Radiation doses and image quality metrics were compared for the standard and low-dose protocol patients. RESULTS: Effective dose significantly decreased 84% to 91% depending on patient size and whether the scan was preoperative or postoperative. All scans were compatible with the navigation software. No clinically significant differences in image quality were observed between low-dose and standard patient cohorts. CONCLUSIONS: Task-based CT protocol optimization can produce acceptable image quality with dose comparable to standard two-view radiography. LEVEL OF EVIDENCE: 2.

Juvenile myelomonocytic leukemia presenting as bilateral breast masses.

An 8-year-old girl presented with bilateral breast masses and was subsequently diagnosed with juvenile myelomonocytic leukemia. Juvenile myelomonocytic leukemia is a rare myelodysplastic syndrome that typically presents in boys younger than 3 years of age with splenomegaly, lymphadenopathy and skin findings. Bilateral breast masses in a child are rare and, as such, present a diagnostic dilemma due to the relative paucity of cases in the literature. We present a case of granulocytic sarcoma of the breasts in a patient with juvenile myelomonocytic leukemia. The authors hope that increased reporting and research regarding pediatric breast masses will help create awareness for such cases.

Imaging of Sports-related Injuries of the Lower Extremity in Pediatric Patients.

With increasing participation and intensity of training in youth sports in the United States, the incidence of sports-related injuries is increasing, and the types of injuries are shifting. In this article, the authors review sports injuries of the lower extremity, including both acute and overuse injuries, that are common in or specific to the pediatric population. Common traumatic injuries that occur in individuals of all ages (eg, tears of the acetabular labrum and anterior cruciate ligament) are not addressed, although these occur routinely in pediatric sports. However, some injuries that occur almost exclusively in high-level athletes (eg, athletic pubalgia) are reviewed to increase awareness and understanding of these entities among pediatric radiologists who may not be familiar with them and thus may not look for them. Injuries are described according to their location (ie, hip, knee, or foot and ankle) and pathologic process (eg, apophysitis, osteochondritis dissecans). Examples of abnormalities and normal variants of the anatomy that are often misdiagnosed are provided. The injuries reviewed represent a common and growing subset of pathologic processes about which all pediatric and musculoskeletal radiologists should be knowledgeable. Understanding physeal injury is especially important because missed diagnoses can lead to premature physeal closure and osteoarthritis. ©RSNA, 2016.

Image quality and dose differences caused by vendor-specific image processing of neonatal radiographs.

BACKGROUND: Image processing plays an important role in optimizing image quality and radiation dose in projection radiography. Unfortunately commercial algorithms are black boxes that are often left at or near vendor default settings rather than being optimized. OBJECTIVE: We hypothesize that different commercial image-processing systems, when left at or near default settings, create significant differences in image quality. We further hypothesize that image-quality differences can be exploited to produce images of equivalent quality but lower radiation dose. MATERIALS AND METHODS: We used a portable radiography system to acquire images on a neonatal chest phantom and recorded the entrance surface air kerma (ESAK). We applied two image-processing systems (Optima XR220amx, by GE Healthcare, Waukesha, WI; and MUSICA(2) by Agfa HealthCare, Mortsel, Belgium) to the images. Seven observers (attending pediatric radiologists and radiology residents) independently assessed image quality using two methods: rating and matching. Image-quality ratings were independently assessed by each observer on a 10-point scale. Matching consisted of each observer matching GE-processed images and Agfa-processed images with equivalent image quality. A total of 210 rating tasks and 42 matching tasks were performed and effective dose was estimated. RESULTS: Median Agfa-processed image-quality ratings were higher than GE-processed ratings. Non-diagnostic ratings were seen over a wider range of doses for GE-processed images than for Agfa-processed images. During matching tasks, observers matched image quality between GE-processed images and Agfa-processed images acquired at a lower effective dose (11 ± 9 µSv; P < 0.0001). CONCLUSION: Image-processing methods significantly impact perceived image quality. These image-quality differences can be exploited to alter protocols and produce images of equivalent image quality but lower doses. Those purchasing projection radiography systems or third-party image-processing software should be aware that image processing can significantly impact image quality when settings are left near default values.

Alkaptonuria.

A 50-year-old woman with a chronic polyarthropathy was seen by her orthopedist for long-standing back and shoulder and worsening hip pain. A lateral labral tear and chronic trochanteric bursitis were diagnosed on hip magnetic resonance imaging, which was otherwise unremarkable. Hip arthroscopy was performed revealing an unusual bluish-tinged femoral head articular surface. Computed tomography scans of the spine were also obtained.

Magnetic Resonance Arthrography of the Wrist and Elbow.

Magnetic resonance (MR) arthrography of the wrist and elbow is useful for detecting a variety of intra-articular pathologies. MR dictations should address whether intrinsic ligament tears of the wrist are partial-thickness or full-thickness, and involve the dorsal, membranous, and/or volar components of the ligaments. With regard to elbow soft tissue pathology, partial-thickness tears of the anterior band of the ulnar collateral ligament in overhead-throwing athletes are well evaluated with MR arthrography. MR arthrography also is helpful in staging osteochondritis dissecans of the capitellum, caused by repetitive valgus impaction injury in adolescent or young adult baseball pitchers.

Cinegraphic versus Combined Static and Cinegraphic Imaging for Initial Cranial Ultrasound Screening in Premature Infants.

BACKGROUND: Cranial ultrasound is an essential screening and diagnostic tool in the care of neonates and is especially useful in the premature population for evaluation of potential germinal matrix/intraventricular hemorrhage (GM/IVH). There are typically two screening examinations, with the initial cranial sonography performed between 3 days and 14 days after birth, usually consisting of a series of static images plus several cinegraphic sweeps. OBJECTIVE: Our primary goal was to assess whether cinegraphic sweeps alone are as accurate for diagnosing neurological abnormalities as combined static and cinegraphic imaging in the initial cranial US evaluation of premature infants. Our secondary goal was to establish the difference in time required to perform these two examinations. MATERIALS AND METHODS: We retrospectively obtained 140 consecutive initial cranial US screening studies of premature infants. Three pediatric radiologists blinded to patient data read cinegraphic images alone and also combined (dual) imaging sets for a subset of subjects, recording findings for seven disease processes: germinal matrix/intraventricular hemorrhage (GM/IVH), right or left side; periventricular leukomalacia (PVL); choroid plexus cyst; subependymal cyst; cerebral and cerebellar infarction or hemorrhage; posterior fossa hemorrhage or infarction, and extra-axial hemorrhage. Separately, we compared retrospective dual imaging acquisition time against prospectively collected cinegraphic imaging time for premature infants undergoing initial cranial US evaluation. RESULTS: Equivalence testing demonstrated no difference in equivalency between initial cranial US screening using cinegraphic evaluation alone and dual imaging for GM/IVH, cerebral and cerebellar infarct or hemorrhage, and subependymal cyst (all P < 0.05). For PVL and choroid plexus cyst, cinegraphic imaging and dual imaging did not demonstrate equivalence (P > 0.05). Cinegraphic images were obtained in less than one-third of the time required for dual imaging. CONCLUSION: For the diagnoses that are critical to establish at initial screening (GM/IVH, cerebral and cerebellar infarct or hemorrhage) initial cranial US screening using cinegraphic sweeps was equivalent to dual imaging. Cinegraphic imaging required significantly less time to perform than dual imaging. We suggest that performance of cranial US screening using cinegraphic imaging alone is a potentially advantageous option in the initial evaluation of the premature neonate.