The results suggest that the performance advantage of expert radiologists is underpinned by superior pattern recognition skills, as evidenced by a quicker time to first fixate the pathology, and less time spent searching the image.

Function studies after total knee arthroplasty (TKA) generally use either self-reported instruments or objective quantitative measurements of walking activities, but it is unclear how objective factors influence self-reports. This retrospective multicenter study assessed the impact of objective variables on subjective self-reported functional outcome after TKA in 128 patients at a mean of 41 months after TKA. Self-reported disability was measured by the Western Ontario and McMaster University (WOMAC) scale, and the quality of walking and representative daily activities were determined objectively by the DynaPort knee test. Objective assessment was found to be a poor predictor of WOMAC abnormality, with correlations of 0.343, 0.246, and 0.269 with WOMAC function, stiffness, and pain, respectively. The results of WOMAC are thus strongly influenced by factors other than quantitative parameters of the lower extremity. These findings provide support for including an objective assessment of activities of daily living together with a subjective self-report.

ABSTRACT. Increasing trainee numbers and changes to working patterns have resulted in a scarcity of training opportunities for training-grade doctors wishing to learn nephrostomy tube insertion techniques. A method of introducing trainees to the skills required to perform percutaneous nephrostomy in a safe, non-threatening environment, without risk to patients, is desirable. Commercial and biological nephrostomy phantoms are available, but they are expensive and not widely available, and a cheap, safe, valid alternative is desirable. We describe a simple technique for producing a gelatin-based phantom, which we suggest has face and content simulator validity. The use of this nephrostomy phantom could optimise existing clinical training opportunities through familiarisation with nephrostomy technique and equipment, and development of the psychomotor skills required for successful nephrostomy insertion prior to undertaking supervised procedures on patients. Skills in ultrasound-guided percutaneous nephrostomy insertion are desirable for trainee radiologists. Nephrostomy is often the method of choice for emergency decompression of an obstructed renal system, particularly in the presence of urinary infection. This intervention is frequently required as an "on-call" procedure. Moreover, the skills required for ultrasound needle guidance and the Seldinger technique are crosstransferable, being of use in the drainage of collections elsewhere in the body and in the performance of ultrasound-guided biopsies. Preferably, trainees should acquire these skills in a safe, non-threatening environment, without patient risk.Commercial nephrostomy phantoms are available and biological phantoms have been described [1,2], but both of these have disadvantages (including cost and hygiene considerations, respectively). Gelatin-based phantoms have been described for developing ultrasound-guided biopsy technique [3,4], but these do not facilitate the complex procedural sequence required to insert a drain into a dilated pelvicalyceal system. A gelatin-based system has recently been described that allows ultrasound-guided puncture of a simulated pelvicalyceal system [5], but the costs and complexity of production may be prohibitive for routine use by trainees. We therefore describe a cheap and relatively simple technique, adapted from previously described methodology [3,4], for producing a gelatinbased phantom that permits ultrasound-guided puncture, wire insertion, serial dilatation and drainage of a fluid-filled cavity that simulates the dilated collecting system of a hydronephrotic kidney.

No abstract

Surgical subcutaneous emphysema is known to be a potential complication of the use of high-speed air-driven dental drills (air turbines) and compressed air syringes. Often, however, we assume that it is just a theoretical risk to be taught to undergraduates that never actually happens in practice. Here, we present a case of extensive surgical subcutaneous emphysema secondary to tongue trauma from a high-speed drill, extending far from the site of air entry.