Cone-beam volumetric tomography for applications in the temporal bone

Hypothesis: Cone beam volumetric tomography (CBVT) has better spatial resolution compared with multi slice computed tomography (MSCT) in temporal bone imaging for superior canal dehiscence (SCD). Background: Imaging of SCD has traditionally used MSCT, but the ability to resolve thin bone next to low-radiodensity brain and inner ear fluids at the interface of the superior canal (SC) with the middle cranial fossa can be adversely affected by partial volume averaging, errors in registration of successive slices, and other factors. CBVT may offer advantages in these regards and may have better spatial resolution for this application. Methods: Five cadaveric temporal bones were scanned using both CBVT and MSCT. The information content at the interface of the SC and the middle cranial fossa was measured for each method using spatial differential transformations. The ability of each method to resolve progressively smaller interfaces between bone and fluid was measured by creating a spatial grating model from a human temporal bone. Results: The information content and spatial resolution were superior for CBVT compared with MSCT. Conclusion: The gold standard for diagnosis of SCD has been MSCT, but CBVT may offer improvements in information content and spatial resolution at the interface of the SC and the middle cranial fossa

Multislice computed tomography in the diagnosis of superior canal dehiscence: how much error, and how to minimize it?

Hypothesis: Multi-slice computed tomography (MSCT) overestimates the size of superior semicircular canal dehiscences (SSCDs) and also can misinterpret thin bone over the superior semicircular canal as dehiscent. A threshold of the radiodensity of the bone over the superior semicircular canal may exist that could optimize prediction of an actual SSCD. Background: The gold standard for diagnosis of SSCD is MSCT, but there is a higher prevalence of SSCD based on MSCT compared with histologic studies. Overestimation of SSCD can lead to inappropriate diagnosis and treatment. Methods: We correlated radiographic and surgical findings in SSCD to determine if MSCT overestimated the size of SSCD and if a threshold radiodensity could be defined, below which actual dehiscence could best be predicted. Participants were 34 humans with SSCD confirmed at surgery. MSCT scans were acquired axially with 0.5-mm collimation and a small field of view (24 cm). Dehiscence sizes measured from radial reconstructions were compared with measurements made during surgery. Results: There were significant differences between radiographic and actual length and width, indicating that MSCT tends to overestimate the size of SSCD. Receiver operating characteristic analysis found a threshold in Hounsfield units that optimized the prediction of dehiscence. Conclusion: Computed tomographic imaging alone can be misleading for diagnosis of SSCD. It can overestimate the size of the dehiscence, and it can falsely detect dehiscences. Clinical symptoms and other signs must be clearly indicative before surgery, and MSCT cannot be used exclusively for the diagnosis of SSCD

Children’s evaluation of verified and unverified claims

Critical to children’s learning is the ability to judiciously select what information to accept–to use as the basis for learning and inference—and what to reject. This becomes especially difficult in a world increasingly inundated with information, where children must carefully reason about the process by which claims are made in order to acquire accurate knowledge. In two experiments, we investigated whether 3- to 7-year-old children (N=120) understand that factual claims based on verified evidence are more acceptable than claims that have not been sufficiently verified. We found that even at preschool age, children evaluated verified claims as more acceptable than insufficiently verified claims, and that the extent to which they did so was related to their explicit understanding, as evident in their explanations of why those claims were more or less acceptable. These studies lay the groundwork for an important line of research studying the roots and development of this foundational critical thinking skill

Deal Me in: Playing Cards in the Home to Learn Math

Recent meta-analyses have demonstrated a significant association between children’s early math achievement and their experiences with math at home, including their caregivers’ talk about math. However, few studies have investigated the relations between caregiver math talk and children’s learning with experimental designs. Eighty-six children (M = 5.0 years) and their caregivers were randomly assigned to play either a numeracy or a shape card game at home for six weeks. Data were collected on children’s number and shape knowledge and families’ math talk during gameplay. There was substantial participant attrition (42% did not return completed materials), however, both an intent-to-treat analysis of the sample that received study materials and a subgroup analysis of study completers showed that children who played the shape game significantly improved their shape naming and matching skills relative to children who played the number game. Children who played the number game did not significantly improve their numerical skills relative to children who played the shape game. Mathematical talk during gameplay varied between families but was correlated over time within families. Caregivers’ and children’s talk about matching cards by shape or color predicted children’s learning from the shape game. The results suggest that despite receiving uniform instructions and materials, there was significant variability in children’s home math experiences that predicted their learning from the card game

Deal Me in: Playing Cards in the Home to Learn Math

Recent meta-analyses have demonstrated a significant association between children’s early math achievement and their experiences with math at home, including their caregivers’ talk about math. However, few studies have investigated the relations between caregiver math talk and children’s learning with experimental designs. Eighty-six children (M = 5.0 years) and their caregivers were randomly assigned to play either a numeracy or a shape card game at home for six weeks. Data were collected on children’s number and shape knowledge and families’ math talk during gameplay. There was substantial participant attrition (42% did not return completed materials), however, both an intent-to-treat analysis of the sample that received study materials and a subgroup analysis of study completers showed that children who played the shape game significantly improved their shape naming and matching skills relative to children who played the number game. Children who played the number game did not significantly improve their numerical skills relative to children who played the shape game. Mathematical talk during gameplay varied between families but was correlated over time within families. Caregivers’ and children’s talk about matching cards by shape or color predicted children’s learning from the shape game. The results suggest that despite receiving uniform instructions and materials, there was significant variability in children’s home math experiences that predicted their learning from the card game