Now showing 1 - 10 of 26
  • Publication
    Poor agreement between operators on grading of the placenta
    Abnormal placental grading is associated with poor pregnancy outcome. The aim of this study was to measure intra- and interobserver variability in placental grading. Five expert sonographers independently graded 90 images on two occasions, each viewing separated by 1 week. A number of measures were employed to standardise assessment and minimise potential for variation: prior agreement was established between observers on the classifications for placental grading; a controlled viewing laboratory was used for all viewings; ambient lighting was optimal and monitors were calibrated to the GSDF standard. Kappa (κ) analysis was used to measure observer agreement. Substantial variations between individuals' scores were observed. A mean κ-value of 0.34 (range from 0.19 to 0.50) indicated fair interobserver agreement over the two occasions and only nine of the 90 images were graded the same by all five observers. Intraobserver agreement had a moderate mean κ-value of 0.52, with individual comparisons ranging from 0.45 to 0.66. This study demonstrates that, despite standardised viewing conditions, Grannum grading of the placenta is not a reliable technique even among expert observers. The need for new methods to assess placental health is required and work is ongoing to develop 2D and 3D software-based methods.
      689Scopus© Citations 18
  • Publication
    Gait Biomechanics in Participants, Six Months after First-Time Lateral Ankle Sprain
    No research currently exists predicating a link between the injury-affiliated sensorimotor deficits of acute ankle sprain and those of chronic ankle instability during gait. This analysis evaluates participants with a 6-month history of ankle sprain injury to affirm this link. 69 participants with a 6-month history of acute first-time lateral ankle sprain were divided into subgroups (‘chronic ankle instability’ and 'coper') based on their self-reported disability and compared to 20 non-injured participants during a gait task. Lower extremity kinematic and kinetic data were collected from 200 ms pre- to 200 ms post-heel strike (period 1) and from 200 ms pre- to 200 ms post-toe off (period 2). The ‘chronic ankle instability’ subgroup (who reported greater disability) displayed increased knee flexion during period 1. During period 2, this subgroup exhibited greater total displacement at their ankle joint and greater extensor dominance at their knee. That many of these features are present, both in individuals with acute ankle sprain and those with chronic ankle instability may advocate a link between acute deficits and long-term outcome. Clinicians must be aware that the sensorimotor deficits of ankle sprain may persevere beyond the acute stage of injury and be cognizant of the capacity for impairments to pervade proximally.
      653Scopus© Citations 8
  • Publication
    3D Power Doppler ultrasound and computerised placental assessment in normal pregnancy
    Background: In recent years there have been significant developments in the use of 3D Power Doppler (3DPD) imaging and quantitative 3DPD histogram analysis to estimate both placental volume and intra-placental vasculature. This study aims to determine if placental volume, vascularisation and blood flow are correlated with gestational age in normal pregnancy. It also examines whether or not a new software method for analysis of percentage calcification (the ‘placentometer’) correlates well with gestation. Material and method: This was a prospective cohort study of 250 women with normal pregnancies (12 + 6 to 39 + 5 weeks gestation). 3DPD ultrasound was used to evaluate placental volume, vascularisation index (VI), flow index (FI) and vascularisation-flow index (VFI). Placental volume (calculated at 35–40 weeks gestation), was correlated with birth weight. Following each scan the percentage of calcification was also calculated using the placentometer. Results: Placental volume correlated significantly with gestational age: 66.676 + 0.623 × GA (P < 0.001). No significant change with gestation was noted in VI, FI and VFI (VI: P = 0.199, FI: P = 0.299, VFI: P = 0.557). Software analysis of the percentage of calcification, demonstrated the expected increase in calcification as gestation increased: −4.605 + 0.032 × GA (P < 0.001). From 35 to 40 weeks gestation volume was related to birth weight (P < 0.01). Conclusion: This study shows that in normal low-risk pregnancy placental volume increases with gestational age, whereas vascularisation and blood flow are independent of gestation. Placental volume in late pregnancy is related to birth weight. Software analysis of the percentage of calcification demonstrates an increase with advancing gestation.
      423Scopus© Citations 5
  • Publication
    Recovery From a First-Time Lateral Ankle Sprain and the Predictors of Chronic Ankle Instability: A Prospective Cohort Analysis
    Background: Impairments in motor control may predicate the paradigm of chronic ankle instability (CAI) that can develop in the year after an acute lateral ankle sprain (LAS) injury. No prospective analysis is currently available identifying the mechanisms by which these impairments develop and contribute to long-term outcome after LAS. Purpose: To identify the motor control deficits predicating CAI outcome after a first-time LAS injury. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: Eighty-two individuals were recruited after sustaining a first-time LAS injury. Several biomechanical analyses were performed for these individuals, who completed 5 movement tasks at 3 time points: (1) 2 weeks, (2) 6 months, and (3) 12 months after LAS occurrence. A logistic regression analysis of several "salient" biomechanical parameters identified from the movement tasks, in addition to scores from the Cumberland Ankle Instability Tool and the Foot and Ankle Ability Measure (FAAM) recorded at the 2-week and 6-month time points, were used as predictors of 12-month outcome. Results: At the 2-week time point, an inability to complete 2 of the movement tasks (a single-leg drop landing and a drop vertical jump) was predictive of CAI outcome and correctly classified 67.6% of cases (sensitivity, 83%; specificity, 55%; P = .004). At the 6-month time point, several deficits exhibited by the CAI group during 1 of the movement tasks (reach distances and sagittal plane joint positions at the hip, knee and ankle during the posterior reach directions of the Star Excursion Balance Test) and their scores on the activities of daily living subscale of the FAAM were predictive of outcome and correctly classified 84.8% of cases (sensitivity, 75%; specificity, 91%; P < .001). Conclusion: An inability to complete jumping and landing tasks within 2 weeks of a first-time LAS and poorer dynamic postural control and lower self-reported function 6 months after a first-time LAS were predictive of eventual CAI outcome.
      2684Scopus© Citations 262
  • Publication
    Single-leg drop landing motor control strategies following acute ankle sprain injury
    No research currently exists investigating the effect of acute injury on single-limb landing strategies. The aim of the current study was to analyse the coordination strategies of participants in the acute phase of lateral ankle sprain (LAS) injury. Thirty-seven participants with acute, first-time, LAS and nineteen uninjured participants completed a single-leg drop landing task (DL) on both limbs. 3-dimensional kinematic (angular displacement) and sagittal plane kinetic (moment of force) data were acquired for the joints of the lower extremity, from 200ms pre-initial contact (IC) to 200ms post IC. The peak magnitude of the vertical component of the ground reaction force (GRF) was also computed. Injured participants displayed a bilateral increase in hip flexion, with altered transverse plane kinematic profiles at the knee and ankle for both limbs (p < 0.05). This coincided with a reduction in the net supporting flexor moment of the lower extremity (p < 0.05) and magnitude of the peak vertical GRF for the injured limb (21.82 ± 2.44 N/kg vs 24.09 ± 2.77 N/kg; p = 0.013) in injured participants compared to control participants. These results demonstrate that compensatory movement strategies are utilized by participants with acute LAS to successfully reduce the impact forces of landing.
      1231Scopus© Citations 35
  • Publication
    Is Grannum Grading of the Placenta Reproducible?
    Current ultrasound assessment of placental calcification relies on Grannum grading. The aim of this study was to assess if this method is reproducible by measuring inter- and intra-observer variation in grading placental images, under strictly controlled viewing conditions. Thirty placental images were acquired and digitally saved. Five experienced sonographers independently graded the images on two separate occasions. In order to eliminate any technological factors which could affect data reliability and consistency all observers reviewed images at the same time. To optimise viewing conditions ambient lighting was maintained between 25-40 lux, with monitors calibrated to the GSDF standard to ensure consistent brightness and contrast. Kappa (κ) analysis of the grades assigned was used to measure inter- and intra-observer reliability. Intra-observer agreement had a moderate mean κ-value of 0.55, with individual comparisons ranging from 0.30 to 0.86. Two images saved from the same patient, during the same scan, were each graded as I, II and III by the same observer. A mean κ-value of 0.30 (range from 0.13 to 0.55) indicated fair inter-observer agreement over the two occasions and only one image was graded consistently the same by all five observers. The study findings confirmed the lack of reproducibility associated with Grannum grading of the placenta despite optimal viewing conditions and highlight the need for new methods of assessing placental health in order to improve neonatal outcomes. Alternative methods for quantifying placental calcification such as a software based technique and 3D ultrasound assessment need to be explored.
      426Scopus© Citations 2
  • Publication
    Variability of Breast Density Classification Between US and UK Radiologists
    Purpose: To assess whether subjective breast density categorization remains the most useful way to categorize mammographic breast density and whether variations exist across geographic regions with differing national legislation. Methods: Breast radiologists from two countries (UK, USA) were voluntarily recruited to review sets of anonymized mammographic images (n = 180) and additional repeated images (n = 70), totaling 250 images, to subjectively rate breast density according to the Breast Imaging Reporting and Data system (BI-RADS) categorization. Images were reviewed using standardized viewing conditions and Ziltron software. Inter-rater reliability was analyzed using the Kappa test. Results: The US radiologists (n = 25) judged fewer images as being “mostly fatty” than UK radiologists (n = 24), leading a greater number of images classified in the higher BI-RADS categories, particularly in BI-RADS 3. Overall agreement for all data sets was k = 0.654 indicating substantial agreement between the two cohorts. When the data were split into BI-RADS categories, the level of agreement varied from fair to substantial. Conclusion: Variations in how radiologists from the USA and UK classify breast density was established, especially when the data were divided into breast density categories. This variation supports the need for a reliable breast density assessment method to enhance the individualized supplemental screening pathways for dense breasts. The use of two-scale categorization method demonstrated improved agreement.
    Scopus© Citations 12  401
  • Publication
    Single-leg drop landing movement strategies in participants with chronic ankle instability compared with lateral ankle sprain 'copers'
    Individuals with CAI display alterations in hip joint kinematics and energetics during a unipodal landing task compared to LAS 'copers'. These alterations may be responsible for the increased risk of injury experienced by individuals with CAI during landing manoeuvres. Thus, clinicians must recognise the potential for joints proximal to the affected ankle to contribute to impaired function following an acute lateral ankle sprain injury and to develop rehabilitation protocols accordingly.
      1205Scopus© Citations 48
  • Publication
    A review of cross sectional imaging, ultrasound & nuclear medicine utilisation patterns in paediatric patients in Ireland, 2003-12
    (British Institute of Radiology, 2015-02-26) ; ;
    Objective: Recent trends in paediatric imaging have been examined in Australia and the USA. Such literature in Europe is sparse, incomprehensive and outdated. This research investigated (1) population-based trends in the use of advanced medical imaging in children in Ireland from 2003 to 2012; (2) its use across age and gender; and (3) the most commonly performed examinations within each modality. Methods: A retrospective cohort analysis study was carried out within Irish paediatric hospitals. All CT, MRI, ultrasound and nuclear medicine (NM) annual examination data from 2003 to 2012 was obtained from radiology information systems. Results: 224,173 imaging procedures were carried out on 84,511 patients, 68% of which were ultrasound, 15% were MRI, 11% were CT and 6% were NM. Between 2003 and 2012, MRI (+280%) and CT (+80%) saw the largest increases in use, followed by ultrasound (+67%) and NM (+10%). Almost half of the study population were less than 3 years old. CT imaging was more frequent than MR in 2005. By 2012, MR rates were twice that of CT. CT imaging rates were the lowest in the youngest age categories. Conclusion: Advanced imaging use, particularly MRI, has risen substantially over the past 10 years. The utilization of non-ionizing modalities increased between 2003 and 2012, especially in brain, spinal and abdominal imaging. MR is now used at twice the frequency of CT. Advances in knowledge: Longitudinal advanced imaging utilization trends, including CT trends, have been established in the Irish paediatric population.
      356Scopus© Citations 5
  • Publication
    Best single slice location to measure visceral adipose tissue on paediatric CT scans and the relations between anthropometric measurements, gender and VAT volume in children
    (British Institute of Radiology, 2015-09-21) ; ;
    Objective: Visceral adipose tissue (VAT) is a significant risk factor for obesity-related metabolic diseases. This study investigates (1) the best single CT slice location for predicting total abdominal VAT volume in paediatrics and (2) the relationship between waist circumference (WC), sagittal diameter (SD), gender and VAT volume. Methods: A random sample of 130 paediatric abdomen CT scans, stratified according to age and gender, was collected. Three readers measured VAT area at each intervertebral level between T12 and S1 using ImageJ analysis (National Institute of Health, Bethesda, MD) software by thresholding −190 to −30 HU and manually segmenting VAT. Single-slice VAT measurements were correlated with total VAT volume to identify the most representative slice. WC and SD were measured at L3–L4 and L4–L5 slices, respectively. Regression analysis was used to evaluate WC, SD and gender as VAT volume predictors. Results: Interviewer and intraviewer reliability were excellent (intraclass correlation coefficient = 0.99). Although VAT measured at multiple slices correlated strongly with abdominal VAT, only one slice in females at L2–L3 and two slices in males at L1–L2 and L5–S1 were strongly correlated across all age groups. Linear regression analysis showed that WC was strongly correlated with VAT volume (beta = 0.970, p < 0.001). Conclusion: Single-slice VAT measurements are highly reproducible. Measurements performed at L2–L3 in females and L1–L2 or L5–S1 in males were most representative of VAT. WC is indicative of VAT. Advances in knowledge: VAT should be measured at L2–L3 in female children and at either L1–L2 or L5–S1 in males. WC is a strong indicator of VAT in children.
      415Scopus© Citations 17