Implementation of a brain injury screen MRI for infants at risk for abusive head trauma

BACKGROUND

Head computed tomography (CT) is the current standard of care for evaluating infants at high risk of abusive head trauma.

OBJECTIVE

To both assess the feasibility of using a previously developed magnetic resonance imaging (MRI) brain injury screen (MRBRscreen) in the acute care setting in place of head CT to identify intracranial hemorrhage in high-risk infants and to compare the accuracy of a rapid imaging pulse sequence (single-shot T2 fast spin echo [ssT2FSE]) to a conventional pulse sequence (conventional T2 fast spin echo [conT2FSE]).

MATERIALS AND METHODS

This was a quality improvement initiative to evaluate infants <12 months of age who were screened for intracranial hemorrhage using an MRBRscreen as part of clinical care. The MRBRscreen included axial conT2FSE, axial gradient recalled echo, coronal T1-weighted inversion recovery, axial diffusion-weighted image and an axial ssT2FSE. A comparison of ssT2FSE to conT2FSE with respect to lesion detection was also performed.

RESULTS

Of 158 subjects, the MRBRscreen was able to be completed in 155 (98%); 9% (14/155) were abnormal. Ninety-four percent (137/145) of subjects underwent only an MRBRscreen and avoided both radiation from head CT and sedation from MRI. The axial ssT2FSE and conT2FSE results were congruent 99% of the time.

CONCLUSION

An MRBRscreen in place of a head CT is feasible and potentially could decrease head CT use by more than 90% in this population. Using a rapid ssT2FSE in place of a conT2FSE can reduce total scan time without losing lesion detection. If an MRBRscreen is readily available, physicians' threshold to perform neuroimaging may be lowered and lead to earlier detection of abusive head trauma.

Development and Modification of an Outcome Measure to Follow Symptoms of Children with Sinusitis

OBJECTIVE

To develop a parent-reported Pediatric Rhinosinusitis Symptom Scale (PRSS) that could be used to monitor symptoms of young children with acute sinusitis in response to therapy.

STUDY DESIGN

We developed an 8-item symptom severity scale and evaluated its internal reliability, construct validity, and responsiveness in children 2-12 years of age with acute sinusitis. Parents of 258 children with acute sinusitis completed the PRSS at the time of diagnosis, as a diary at home, and at the follow-up visit at days 10-12. Based on psychometric results and additional parent feedback, we revised the scale. We evaluated the revised version in 185 children with acute sinusitis.

RESULTS

Correlations between the scale and reference measures on the day of enrollment were in the expected direction and of the expected magnitude. PRSS scores at the time of presentation correlated with radiographic findings (P < .001), functional status (P < .001), and parental assessment of overall symptom severity (P < .001). Responsiveness (standardized response mean) and test-retest reliability of the revised scale were good (2.17 and 0.75, respectively).

CONCLUSIONS

We have developed an outcome measure to track the symptoms of acute sinusitis. Data presented here support the use of the PRSS as a measure of change in symptom burden in clinical trials of children with acute sinusitis.

Are nasopharyngeal cultures useful in diagnosis of acute bacterial sinusitis in children?

The diagnosis of acute bacterial sinusitis can be challenging because symptoms of acute sinusitis and an upper respiratory tract infection (URI) overlap. A rapid test, if accurate in differentiating sinusitis from URI, could be helpful in the diagnostic process. We examined the utility of nasopharyngeal cultures in identifying the subgroup of children with a clinical diagnosis of acute sinusitis who are least likely to benefit from antimicrobial therapy (those with completely normal sinus radiographs). Nasopharyngeal swabs were collected from 204 children meeting a priori clinical criteria for acute sinusitis. All children had sinus X-rays at the time of diagnosis. To determine if negative nasopharyngeal culture results could reliably identify the subgroup of children with normal radiographs, we calculated negative predictive values and negative likelihood ratios. Absence of pathogens in the nasopharynx was not helpful in identifying this low-risk subgroup.

Reading performance correlates with white-matter properties in preterm and term children

AIM

We used diffusion tensor imaging to investigate the association between white-matter integrity and reading ability in a cohort of 28 children. Nineteen preterm children (14 males, five females; mean age 11 y 11 mo [SD 1 y 10 mo], mean gestational age 30.5 wks (SD 3.2), mean birthweight was 1455 g [SD 625]); and nine term children (five males, four females; mean age 12 y 8 mo [SD 2 y 5 mo], mean gestational age 39.6 wks (SD 1.2), and mean birthweight 3877 g [SD 473]).

METHOD

We tested whether fractional anisotropy in a left hemisphere temporoparietal region and in the corpus callosum correlates with birthweight and scores on the following three subtests of the Woodcock-Johnson III Tests of Achievement: word identification, word attack, and passage comprehension.

RESULTS

Preterm children had lower reading scores than a comparison group for all reading subtests (p<0.05). We found significant correlations between birthweight and fractional anisotropy in the whole corpus callosum (p=0.001), and between fractional anisotropy and reading skill in the genu (p=0.001) and body (p=0.001) of the corpus callosum. The correlation between reading skill and fractional anisotropy in a left temporoparietal region previously associated with reading disability was not significant (p=0.095).

INTERPRETATION

We conclude that perinatal white-matter injury of the central corpus callosum may have long-term developmental implications for reading performance.

Radiologic evaluation of foreign bodies

The correct selection of a radiologic imaging modality along with knowledge of indirect radiologic findings can help determine the presence and location of a foreign body. Plain radiographs should be the initial screening modality for a suspected foreign body. Whereas most metal and glass foreign bodies are detectable on radiographs, many foreign bodies, including wood, are not. We do not advocate using xeroradiography for the detection of foreign bodies. When a suspected superficial foreign body is not delineated on radiographs, ultrasonography should be the next modality of choice. CT should be reserved for deep foreign bodies or when foreign bodies are not seen on radiographs or ultrasonography but are suspected.

Detection of soft-tissue foreign bodies by plain radiography, xerography, computed tomography, and ultrasonography

Detection of a soft-tissue foreign body is common yet often difficult, particularly when the foreign material is not radiopaque. Various imaging modalities have been advocated for detecting foreign bodies that are not revealed by plain radiography. The abilities of plain radiography, xerography, computed tomography, and ultrasonography to detect glass, wooden, and plastic foreign bodies in an in vitro preparation are compared. While all of these imaging techniques demonstrated a glass foreign body, only ultrasonography clearly identified wooden and plastic foreign bodies.

Effects of 2,4,6-triaminopyrimidine on the electromechanical properties of guinea-pig myocardium

The effects of 2,4,6-triaminopyrimidine (TAP) were studied in vitro on transmembrane potential and contractility in guinea-pig myocardium. In electrically driven Langendorff-perfused hearts, the addition of 1 and 5 mM TAP produced an initial dose-dependent positive inotropic response with no change in resting tension. The activation process was studied by means of microelectrode and tension recording from isolated electrically driven guinea-pig left atrial preparations. TAP (1-10 mM) produced dose-dependent changes in both electrical and mechanical properties of the tissue. In particular, 1,5 and 10 mM TAP increased the action potential duration by approximately 20, 40 and 60% while also increasing contractile strength by approximately 30, 60 and 90%, respectively. The mechanical effects of TAP were also observed in the presence of 10 muM propranolol. Experiments on catecholamine-restored hearts which were depolarized by potassium indicated that the inotropic action of TAP was associated with slow calcium influx channels. The inotropic effects of TAP were reduced by D600, a calcium antagonistic agent. These data are consistent with a hypothesis that the inotropic actions of TAP result from a decrease in potassium conductance as a result of the inhibition of Ca++-K+ interactions at the inner surface of the myocardial membrane.