Automated Analysis of Metacarpal Cortical Thickness in Serial Hand Radiographs

To understand the roles of various genes that influence skeletal bone accumulation and loss, accurate measurement of bone mineralization is needed. However, it is a challenging task to accurately assess bone growth over a person\u27s lifetime. Traditionally, manual analysis of hand radiographs has been used to quantify bone growth, but these measurements are tedious and may be impractical for a large-scale growth study. The aim of this project was to develop a tool to automate the measurement of metacarpal cortical bone thickness in standard hand-wrist radiographs of humans aged 3 months to 70+ years that would be more accurate, precise and efficient than manual radiograph analysis. The task was divided into two parts: development of automatic analysis software and the implementation of the routines in a Graphical User Interface (GUI). The automatic analysis was to ideally execute without user intervention, but we anticipated that not all images would be successfully analyzed. The GUI, therefore, provides the interface for the user to execute the program, review results of the automated routines, make semi-automated and manual corrections, view the quantitative results and growth trend of the participant and save the results of all analyses. The project objectives were attained. Of a test set of about 350 images from participants in a large research study, automatic analysis was successful in approximately 75% of the reasonable quality images and manual intervention allowed the remaining 25% of these images to be successfully analyzed. For images of poorer quality, including many that the Lifespan Health Research Center (LHRC) clients would not expect to be analyzed successfully, the inputs provided by the user allowed approximately 80% to be analyzed, but the remaining 20% could not be analyzed with the software. The developed software tool provides results that are more accurate and precise than those from manual analyses. Measurement accuracy, as assessed by phantom measurements, was approximately 0.5% and interobserver and intraobserver agreement were 92.1% and 96.7%, respectively. Interobserver and intraobserver correlation values for automated analysis were 0.9674 and 0.9929, respectively, versus 0.7000 and 0.7820 for manual analysis. The automated analysis process is also approximately 87.5% more efficient than manual image analysis and automatically generates an output file containing over 160 variables of interest. The software is currently being used successfully to analyze over 17,000 images in a study of human bone growth

Body Positions Used by Healthy and Frail Older Adults to Rise from the Floor

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111270/1/j.1532-5415.2000.tb03874.x.pd

Rising from the Floor in Older Adults

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111267/1/j.1532-5415.1997.tb03088.x.pd

Obstetric anal sphincter injuries before and after the introduction of the Episcissors-60: A multi-centre time series analysis.

Abstract Obstetric anal sphincter injuries before and after the introduction of the Episcissors-60: A multi-centre time series analysis. Paul Ayuk , Allison Farnworth , Jon Rees , Aethele Khunda , Dawn Edmundson , Vinita Raheja , Aarti Ullal , Velauthapillai Ravimohan , Ena Lu , S C Robson Objective To investigate the impact of the Episcissors-60 on obstetric anal sphincter injury (OASI) rates. Study design Observational multi-centre time series analysis at four maternity units in the North-East of England. The main outcome measures were obstetric anal sphincter injury rates and delivery blood loss Results Data were analysed for women who had a vaginal birth of a singleton pregnancy before (11,192) and after (8,064) the introduction of the Episcissors-60. There were 2115 episiotomies before and 1498 after the introduction of the Episcissors-60, of which 1311 (87.5%) were undertaken with the Episcissors-60, 114 (7.6%) with other scissors and the scissors used were not stated in 73 (4.8%) women. There was no significant association between the introduction of Episcissors-60 and the performance of an episiotomy (χ2 = 0.006, p = 0.94). Episiotomy was associated with a significant reduction in OASI rates (1.9% Vs 2.8%, odds ratio = 0.67 [0.51 – 0.86]; p = 0.001). There was no significant association between the introduction of the Episcissors-60 and the occurrence of OASIs in all women (χ2 = 0.6, p= 0.46) or in women who had an episiotomy (χ2 = 0.20, p = 0.71). In women who had an episiotomy, the mean estimated delivery blood loss was 550.3 ± 8.2 ml before and 598.8 ± 10.9 ml after the introduction of the Episcissors-60 (p < 0.001). Conclusion Introduction of the Episcissors-60 was not associated with a change in OASI or episiotomy rates but may be associated with a small increase in delivery blood loss. Key words: Episcissors-60, obstetric anal sphincter injur

The Development of Abstract Letter Representations for Reading: Evidence for the Role of Context

We review evidence that in the course of reading, the visual system computes abstract letter identities (ALIs): a representation of letters that encodes their identity but that abstracts away from their visual appearance. How could the visual system learn such a seemingly nonvisual representation? We propose that different forms of the same letter tend to appear in similar distributions of contexts (in the same words written in different ways) and that this environmental correlation interacts with correlation-based learning mechanisms in the brain to lead to the formation of ALIs. We review a neural network model that demonstrates the feasibility of this common contexts hypothesis and present two experiments confirming some novel predictions: (a) repeatedly presenting arbitrary visual stimuli in common contexts leads those stimuli to be confusable with each other, and (b) different forms of the same letter are more confusable with each other in word-like contexts than in nonword-like contexts. We then extend the model to use real pictures of letters as input and simulate some of the novel empirical findings from the experiments