The deltopectoral flap in the management of tracheostomal stenosis post laryngectomy and radiotherapy.

BACKGROUND: Tracheostomal stenosis is a distressing complication with a high incidence rate post laryngectomy. We aimed to assess the deltopectoral flap (DPF) for tracheostomal stenosis correction in irradiated patients. METHODS: Six patients with tracheostomal stenosis, 3 of whom developed restenosis after prior use of local flaps, were managed using a DPF to reconstruct the defect following a vertical incision release of the stenotic band down to the inferior tracheal cartilaginous ring. Healing absence of restenosis, alleviation of the symptoms of difficulty in breathing and clearance of secretions were considered a successful composite endpoint. RESULTS: Over a median follow-up period of 11 months all patients maintained patency, and symptoms of difficulty in breathing and clearing of secretions were alleviated. CONCLUSION: The deltopectoral flap is a rapid, reliable flap for the management of tracheostomal stenosis in irradiated patients. It brings well-vascularised tissue into the site of reconstruction and, in the short term, stomal patency and symptom relief were achieved.

Short-Range Disorder in TeO2 Melt and Glass.

High-resolution X-ray pair distribution functions for molten and glassy TeO2 reveal coordination numbers nTeO ≈ 4. However, distinct from the known α-, ß-, and γ-TeO2 polymorphs, there is considerable short-range disorder such that no clear cutoff distance between bonded and nonbonded interactions exists. We suggest that this is similar to disorder in δ-TeO2 and arises from a broad distribution of asymmetric Te-O-Te bridges, something that we observe becomes increasingly asymmetric with increasing liquid temperature. Such behavior is qualitatively consistent with existing interpretations of Raman scattering spectra, and equivalent to temperature-induced coordination number reduction, for sufficiently large cutoff radii. Therefore, TeO2 contains a distribution of local environments that are, furthermore, temperature dependent, making it distinct from the canonical single-oxide glass formers. Our results are in good agreement with high-level ab initio cluster calculations.

Overcoming the learning curve in hand-assisted laparoscopic live donor nephrectomy - a study in the animal model.

The demand for kidneys in South Africa is staggering. Only 38% of the kidney transplants done in 2008 were from related living donors. Laparoscopic living donor nephrectomy has been shown to have the advantages of decreased postoperative pain, better cosmesis and a quicker return to work when compared with the open technique. With limited surgical expertise, a realistic model was needed to overcome the learning curve. Methods. A total of 21 nephrectomies were performed on 12 pigs. The transperitoneal hand-assisted laparoscopic technique was used. Results. The median operative time was 75 minutes and the median warm ischaemic time 88 seconds. Three cases were aborted owing to major vascular injuries. Discussion. The advent of laparoscopic techniques has been associated with an increase in morbidity and complications in donor and recipient during the initial learning curve. We found that with our porcine model, 21 nephrectomies were adequate in overcoming the learning curve. After 15 nephrectomies no complications were noted.

Hand-assisted laparoscopic live donor nephrectomy - initial experience.

INTRODUCTION: The advantages of minimally invasive live donor nephrectomy have been well documented, with no adverse effect on graft function. Minimal access nephrectomy has now become the standard of care in many units. We have adopted the hand-assisted laparoscopic live donor (HALLDN) technique, and present our initial experience with the first 24 cases. MATERIAL AND METHODS: HALLDNs were performed trans-peritoneally. Primary outcomes included total operative time, warm ischaemic time, time to discharge, and post-operative complications. Warm ischaemic time was measured from the time of clamping the renal artery to the time of perfusing the kidney on the back table. RESULTS: Mean total operative time was 143 minutes and mean warm ischaemic time was 188 seconds. A downward trend was displayed for operative times. Mean time to discharge was 60 hours. A right nephrectomy was performed in 2 cases. No surgical morbidity is reported. We describe 1 donor mortality. DISCUSSION: Our results compare favourably with those documented in the literature. Aberrant renal vascular anatomy had no adverse effect on operative or warm ischaemic times. HALLDN proved beneficial in patients with a high BMI. CONCLUSION: Surgical experience is vital when performing HALLDN. Overcoming the learning curve with an animal model is beneficial.

Theoretical study of glass systems using molecular electronic structure theory. 2. Structure and spectroscopy of the B2O3 glass.

The structure and spectroscopic properties of B 2O 3 glass are examined from a theoretical point of view by using a model of 20 B 2O 3 molecules at the DFT/6-31G* level of theory and no predetermined constraints. Useful results are deduced regarding the structure, the fraction of boroxol rings, and the infrared and Raman spectra.