Comparison of MRI and conventional radiography for assessment of acromial shape

OBJECTIVE: Our aim was to determine the value of different MRI planes independently and in combination for assessment of acromial shape. MATERIALS AND METHODS: Sixty-one patients with subacromial impingement syndrome who had undergone acromioplasty after failure to respond to conservative treatment were included in the study. Parasagittal T2-weighted MR images and outlet view radiographs of the affected shoulders were acquired preoperatively. Three-dimensional models of all acromions were constructed from the MR images, and the Bigliani type of acromion depicted by these models was determined. Results were compared with the acromial type assessed during acromioplasty. To provide a reliable reference for further processing and correlation, we used only those 56 acromions with agreement on acromial shape between intraoperative findings and 3D models. Then, acromial shape was determined for three MRI slice positions (S-1, lateral acromial edge; S-2, just lateral of acromioclavicular joint; and S-3, lateral portion of acromioclavicular joint), for a combination of S-1 and S-2, and for the radiographs. RESULTS: Kappa coefficients were 0.36 (36%) for S-1, 0.41 (41%) for S-2, and -0.10 (-10%) for S-3. For the outlet view radiographs, the kappa coefficient was 0.55 (55%), showing better correlation than any single slice position. Best results, however, were achieved with a combination of S-1 and S-2, with a kappa coefficient of 0.66 (66%). CONCLUSION: For determination of acromial shape, outlet view radiographs are superior to any single MRI slice position, but inferior to a combination of two MRI slices (S-1 and S-2). If a single MRI slice is being used, the slice position just lateral to the acromioclavicular joint is recommended.     

Prevalence, course, and predictors of emotional distress in pregnant and parenting adolescents

This study examines trajectories and correlates of emotional distress symptoms in pregnant adolescents (n = 203) and nulliparous adolescents (n = 188) from economically disadvantaged communities over an 18-month period. For both groups, the prevalence of significant emotional distress exceeded expectation based on adolescent norms; however, the severity of symptoms did not differ between the 2 groups. Results from growth curve modeling revealed a significant decline in symptoms during the study period for both groups, but pregnant adolescents experienced a different pattern of decline. Also, certain interpersonal factors (e.g., history of physical maltreatment, partner support) appeared to play a more important role in the emotional well-being of pregnant and parenting adolescents relative to nulliparous adolescents. Implications for early identification and intervention are discussed.     

Racial discrepancies in the association between paternal vs. maternal educational level and risk of low birthweight in Washington State

Background  

The role of paternal factors in determining the risk of adverse pregnancy outcomes has received less attention than maternal factors. Similarly, the interaction between the effects of race and socioeconomic status (SES) on pregnancy outcomes is not well known. Our objective was to assess the relative importance of paternal vs. maternal education in relation to risk of low birth weight (LBW) across different racial groups.     

Variations in adrenal androgen production among (nonhuman) primates

The synthesis and secretion of the adrenal androgens dehydroepiandrosterone (DHEA) and its sulfate (DS) is a phenomenon apparently unique to humans and nonhuman primates. It occurs at three life stages: in utero from the fetal zone (FZ) cells of the developing adrenal cortex, during adolescence with the onset of adrenarche and the development of the zona reticularis (ZR), and in ever decreasing amounts from the ZR with aging (adrenal senescence). Insufficient data exist to know if any single nonhuman primate exactly mirrors human adrenal androgen secretion through all three life stages, and detailed morphological, biochemical, and endocrinologic studies are required to do so. Androgen synthesis requires that cells express three key enzymes, 17alpha-hydroxylase/17,20-lyase cytochrome P450 (P450c17), nicotinamide-adenine dinucleotide phosphate (NADPH)-cytochrome P450 oxidoreductase (CPR), and cytochrome b5, and that they do not express 3beta-hydroxysteroid dehydrogenase (3beta-HSD). Cytochrome b5 has emerged as a particularly useful marker of androgen synthetic potential. Although a reliable index of the rate of adrenal androgen secretion, DS concentrations may not accurately reflect total adrenal androgen output because rates and routes of androgen metabolism may vary greatly among species. Based on the very limited available data, the most promising nonhuman primate models are marmosets for the human FZ, chimpanzees for human adrenarche, and macaques and baboons for mature ZR function that declines with senescence.     

MMP-2 and MMP-9 and their tissue inhibitors in the plasma of preterm and term neonates

Matrix metalloproteinases (MMP) and their tissue inhibitors (TIMP) are involved in a variety of physiologic growth and development and pathophysiologic inflammatory conditions. We hypothesized that 1) MMP-2 and -9 plasma activities and TIMP-1 and -2 plasma concentrations in preterm and term neonates were dependent on the gestational and postnatal age; and 2) the respective MMP and their inhibitors were deranged in the development of bronchopulmonary dysplasia (BPD) and intraventricular hemorrhage (IVH) in preterm neonates. From 1998 to 1999, blood samples were collected from preterm neonates (25-36 wk gestation) with or without BPD and/or IVH as well as from healthy term (37-40 wk gestation) neonates during the first 28 d of life. MMP-2 and MMP-9 plasma activities were measured by zymography; TIMP-1 and TIMP-2 plasma concentrations were determined by ELISA. In neonates without BPD or IVH (n = 50), MMP-2 and MMP-9 plasma activities both appeared to be gestational age dependent, with the highest levels observed in neonates of 33-36 wk gestation. TIMP-1 plasma concentration was highest in term neonates but no gestational difference was found in TIMP-2. Only MMP-9 showed a 50% decrease after d 1 in the first postnatal month. Twelve preterm infants with BPD and/or IVH had significantly lower MMP-2 but higher MMP-9 activity and higher TIMP-1 concentration than those of corresponding neonates without BPD or IVH. These findings show the gestational age-dependent expression of plasma MMP activities and their inhibitors. MMP and TIMP may be involved in the feto-neonatal development and may contribute to the pathogenesis of BPD and/or IVH in critically ill preterm neonates.     

Fungal biofilm formation on cochlear implant hardware after antibiotic-induced fungal overgrowth within the middle ear

Cochlear implantation in patients with chronic suppurative otitis media is managed with perioperative antibiotics; however, fungal overgrowth can occur. We present a child who received oral cefdinir and topical ofloxacin (Floxin). After 6 weeks, a fungal (Candida) biofilm was demonstrated on the implant surface. In this clinical setting, an antimicrobial strategy using an oral antifungal to prevent fungal overgrowth is a possibility.     

Electrophysiologic effects of placing cochlear implant electrodes in a perimodiolar position in young children

OBJECTIVE: The purpose of this study was to intraoperatively record the electrically evoked auditory brainstem response (EABR) before and after placement of the electrode positioning system (EPS) (CII Bionic Ear with HiFocus I cochlear implant electrode array) as well as before and after stylet removal (Nucleus Contour cochlear implant electrode array). It was hypothesized that physiologic changes would occur after perimodiolar positioning of the electrode array and these changes would be evident from the EABR recordings. STUDY DESIGN: Consecutive young (11-36 month old) pediatric cochlear implant recipients (n = 17) had intraoperative EABRs recorded from three intracochlear electrodes that represented apical, medial, and basal locations. Wave V amplitudes and thresholds were studied relative to electrode location and pre- versus postperimodiolar positioning. These evoked potential measures were analyzed for statistical significance. SETTING: Tertiary referral children's hospital/medical college. RESULTS: Wave V thresholds of the EABR were lower, and amplitudes were larger after perimodiolar positioning, although the changes were dependent on electrode location and implant design. Statistically significant decreases in EABR wave V threshold and increases in suprathreshold wave V amplitude were found for the basal electrode for the CII Bionic Ear HiFocus I and for the apical electrode for the Nucleus Contour. CONCLUSIONS: Placement of either the CII Bionic Ear HiFocus I or Nucleus Contour cochlear implant electrode array in the perimodiolar position in young children resulted in less electrical current necessary to stimulate the auditory system. Changes in electrophysiologic thresholds and amplitudes, measured with EABR, indicate that the electrode array is placed closer to the modiolus with both electrode designs.