Detection of Osteoporosis from Percussion Responses Using an Electronic Stethoscope and Machine Learning.

Osteoporosis is an asymptomatic bone condition that affects a large proportion of the elderly population around the world, resulting in increased bone fragility and increased risk of fracture. Previous studies had shown that the vibroacoustic response of bone can indicate the quality of the bone condition. Therefore, the aim of the authors' project is to develop a new method to exploit this phenomenon to improve detection of osteoporosis in individuals. In this paper a method is described that uses a reflex hammer to exert testing stimuli on a patient's tibia and an electronic stethoscope to acquire the impulse responses. The signals are processed as mel frequency cepstrum coefficients and passed through an artificial neural network to determine the likelihood of osteoporosis from the tibia's impulse responses. Following some discussions of the mechanism and procedure, this paper details the signal acquisition using the stethoscope and the subsequent signal processing and the statistical machine learning algorithm. Pilot testing with 12 patients achieved over 80% sensitivity with a false positive rate below 30% and accuracies in the region of 70%. An extended dataset of 110 patients achieved an error rate of 30% with some room for improvement in the algorithm. By using common clinical apparatus and strategic machine learning, this method might be suitable as a large population screening test for the early diagnosis of osteoporosis, thus avoiding secondary complications.

[New technique for intestinal lengthening -- from the idea to the clinical application]. / Új bélhosszabbító mutéti technika -- az ötlettol a klinikumig.

INTRODUCTION: In severe short bowel syndrome, as a result of the natural adaptation, the bowel becomes overdilated, this interferes with the persitalsis and may lead to stasis, bacterial translocation and sepsis. At present two techniques are used to improve peristalsis. The Bianchi procedure is technically challenging, the Serial Transverse Enteroplasty (STEP) is easy however it results in an aphysiological ultrastructure altering the orientation of the muscle fibres. Our aim was to develop an easy technique, which does not alter intestinal muscular ultrastructure dramatically. MATERIAL AND METHODS: The idea, Spiral Intestinal Lengthening and Tailoring (SILT), is based on a spiral shape incision of the intestine and retubularisation in a longer but narrower fashion. The feasibility and the effect on the muscular ultrastructure were tested on bowelsimulator and porcine intestine. The intramural microcirculation was checked with intravital microscopy. The outcome was assessed on minipigs (n = 6) than clinical application was commenced. RESULTS: SILT was feasible, did not change the orientation of muscle fibres significantly, did not compromised microcirculation, no surgical complication was noted when tailoring did not exceed 75%. The first clinical application was successful. CONCLUSION: SILT is a safe and easy technique and not altering the intestinal musculature significantly.

Short-term adaptation of rat intestine to ileostomy: implication for pediatric practice.

BACKGROUND: Surgical neonates with complex intestinal conditions, such as enterocolitis, midgut volvulus with bowel loss and multiple atresias, often require temporary stomas. Little is known on the postsurgical response of the altered gut segments, although adaptation is an important consideration in neonatal postoperative care, particularly after stoma closure. MATERIALS AND METHODS: Rats underwent bowel resection at a point 15 cm proximal to the ileocecal valve, and a split ileostomy was performed. On the 6th postoperative day the mucosal thickness was calculated with Soft Imaging System Analysis Pro, the rate of proliferation was measured following Ki67 immunohistochemistry and the apoptotic index was determined on sections stained with ApopTag Plus. The intestinal motor activity was recorded on isolated gut segments. Neuronal nitric oxide synthase (nNOS) expression and distribution was examined with NADPH-diaphorase histochemistry and Western blot analysis. RESULTS: An increased wet weight of the mucosa and a pronounced mucosal thickening were observed in the proximal functional bowel segment. Enterocyte proliferation rate was increased significantly, while the apoptotic index remained unchanged in the epithelial layer. The dilation of the gut lumen resulted in a morphological change in the nitrergic myenteric network with an overexpression of nNOS. As a consequence of the surgical procedure, the functional proximal gut segment showed strong and frequent contraction waves, with an enhanced responsiveness to cholinergic stimuli. CONCLUSIONS: The dilated functional bowel segment was characterized by hyperplasic changes in the mucosa and stronger mechanical activity with overproduction of nNOS. Although early restoration of intestinal continuity is recommended, our observations on adaptive changes may partly explain intestinal motility disorders after early stoma closure, suggesting the need for a careful approach to a redo-laparotomy.

Central venous line dressings: can you stick it?

AIM: The objective of this study is to investigate which central venous catheter dressing is most secure. BACKGROUND: Central venous catheter insertion is a common procedure. A secure dressing is essential to prevent early line displacement. Many different dressings are used, but there is no consensus in choosing an optimal dressing. METHODS: A sandwich, loop-line, or bridge technique was used to apply each of the dressings. Two mechanisms of displacement were tested: dressing adherence to skin and dressing adherence to line. Dressing to skin adherence was tested on a relatively hairless part of the upper arm. Weights were added sequentially until the dressing peeled off. Dressing to line adherence was tested by applying the dressing to a 7F Dual Lumen Bard Hickman line passing through a piece of foam (measuring 13 x 12 cm). Weights were attached to the line until the cuff was pulled through the foam. RESULTS: Dressing to skin adherence was poorest for the clear dressings, followed by Mefix and Sleek, and greatest for a combination of Tegaderm and Mefix. Dressing to line adherence was improved using a sandwich technique instead of a loop-line technique and most secure when a bridge technique was used to the thicker shaft of the line. CONCLUSIONS: The dressings used for securing Hickman lines are not all equally secure. The least effective is the IV 3000 loop-line dressing. Tegaderm-Mefix bridge and Tegaderm-Mefix-Sleek combination dressings are the most secure and cost effective.