Does Manual Abdominal Pressure During Colonoscopy Put Endoscopy Staff and Patients at Risk? Experiences of Endoscopy Nurses and Technicians.

Endoscopy staff suffer work-related musculoskeletal disorders at a rate greater than or comparable to nurses and technicians in other subspecialities, which may be attributable to the widespread use of manual pressure and repositioning during colonoscopy. In addition to negatively impacting staff health and job performance, colonoscopy-related musculoskeletal disorder injuries may also signal potential risks to patient safety. To assess the prevalence of staff injury and perceived patient harm relating to the use of manual pressure and repositioning techniques during colonoscopy, 185 attendees of a recent national meeting of the Society of Gastroenterology Nurses and Associates were asked to recall experiencing injuries to themselves or observing injuries to other staff or patients during colonoscopy. A majority of respondents (84.9%, n = 157) reported either experiencing or observing staff injury, whereas 25.9% ( n = 48) reported observing patient complications. Among respondents who perform manual repositioning and apply manual pressure during colonoscopy (57.3%, n = 106), 85.8% ( n = 91) reported experiencing musculoskeletal disorders from performing these tasks; 81.1% ( n = 150) reported no awareness of colonoscopy-specific ergonomics policies at their facility. Results highlight the relationship between the physical job requirements of endoscopy nurses and technicians, staff musculoskeletal disorders, and patient complications, and suggest that implementation of staff safety protocols may benefit patients as well as endoscopy staff.

Quantifying the architectural complexity of microscopic images of histology specimens.

Tumour grade (a measure of the degree of cellular differentiation of malignant neoplasm) is an important prognostic factor in many types of cancer. In general, poorly differentiated tumours are characterized by a higher degree of architectural irregularity and complexity of histological structures. Fractal dimension is a useful parameter for characterizing complex irregular structures. However, one of the difficulties of estimating the fractal dimension from microscopic images is the segmentation of pathologically relevant structures for analysis. A commonly used technique to segment structures of interest is to apply a pixel intensity threshold to convert the original image to binary and extract pixel outline structures from the binary representation. The difficulty with this approach is that the value of the threshold required to segment the histological structures is highly dependent on the staining technique chosen and imaging conditions (i.e., illumination time, intensity, and uniformity) of the microscopic system. In this work, we present a method for finding the optimal intensity threshold by maximizing the corresponding fractal dimension. This method results in the segmentation of histological structures and the estimation of their fractal dimension (independent of imaging conditions). We applied our technique to 164 prostate histology sections from 82 prostate core biopsy specimens (two serial sections from each of the 63 benign prostate tissues and 19 high grade prostate carcinoma). We stained one of the serial sections with conventional hemotoxylin and eosin (H&E) and the other with pan-keratin, and found that the difference in mean fractal dimension between the two groups was statistically significant (p<0.0001) for both stains. However, using receiver operating characteristics (ROC) analysis, we conclude that our fractal dimension method applied to the images of pan-keratin stained sections provides greater classification performance (benign versus high grade) than with those stained with H&E when compared to the original histological diagnosis. The sensitivity and specificity achieved with the pan-keratin images were 89.5% and 90.5%, respectively.