Methods to increase response to postal and electronic questionnaires.

Background: Self-administered questionnaires are widely used to collect data in epidemiological research, but non-response reduces the effective sample size and can introduce bias. Finding ways to increase response to postal and electronic questionnaires would improve the quality of epidemiological research.

Objectives: To identify effective strategies to increase response to postal and electronic questionnaires.

Image-guided robotic interventions for prostate cancer.

Robotic prostatectomy is a common surgical treatment for men with prostate cancer, with some studies estimating that 80% of prostatectomies now performed in the USA are done so robotically. Despite the technical advantages offered by robotic systems, functional and oncological outcomes of prostatectomy can still be improved further. Alternative minimally invasive treatments that have also adopted robotic platforms include brachytherapy and high-intensity focused ultrasonography (HIFU).

A comprehensive cardiac motion estimation framework using both untagged and 3-D tagged MR images based on nonrigid registration.

In this paper, we present a novel technique based on nonrigid image registration for myocardial motion estimation using both untagged and 3-D tagged MR images. The novel aspect of our technique is its simultaneous usage of complementary information from both untagged and 3-D tagged MR images. To estimate the motion within the myocardium, we register a sequence of tagged and untagged MR images during the cardiac cycle to a set of reference tagged and untagged MR images at end-diastole.

Caffeine for the prevention of injuries and errors in shift workers.

Background: Sleepiness leads to a deterioration in performance and attention, and is associated with an increased risk of injury. Jet lag and shift work disorder are circadian rhythm sleep disorders which result in sleepiness and can elevate injury risk. They create a need for individuals to operate at times which are different to those dictated by their circadian rhythms.

Methods to increase response to postal and electronic questionnaires.

Background: Postal and electronic questionnaires are widely used for data collection in epidemiological studies but non-response reduces the effective sample size and can introduce bias. Finding ways to increase response to postal and electronic questionnaires would improve the quality of health research.

Objectives: To identify effective strategies to increase response to postal and electronic questionnaires.

Interventions for preventing injuries caused by impaired alertness in individuals with jet lag and shift work disorder.

This is the protocol for a review and there is no abstract. The objectives are as follows: To assess the effects of interventions for preventing injuries caused by impaired alertness in persons with jet lag or shift work disorder.

Non-rigid reconstruction of the beating heart surface for minimally invasive cardiac surgery.

This paper presents a new method to reconstruct the beating heart surface based on the non-rigid structure from motion technique using preprocessed endoscopic images. First the images captured at the same phase within each heart cycle are automatically extracted from the original image sequence to reduce the dimension of the deformation subspace. Then the remaining residual non-rigid motion is restricted to lie within a low-dimensional subspace and a probabilistic model is used to recover the 3D structure and camera motion simultaneously.

Instantiation and registration of statistical shape models of the femur and pelvis using 3D ultrasound imaging.

Statistical shape modelling potentially provides a powerful tool for generating patient-specific, 3D representations of bony anatomy for computer-aided orthopaedic surgery (CAOS) without the need for a preoperative CT scan. Furthermore, freehand 3D ultrasound (US) provides a non-invasive method for digitising bone surfaces in the operating theatre that enables a much greater region to be sampled compared with conventional direct-contact (i.e.

Postoperative calculation of acetabular cup position using 2-D-3-D registration.

A method to accurately measure the position and orientation of an acetabular cup implant from postoperative X-rays has been designed and validated. The method uses 2-D-3-D registration to align both the prosthesis and the preoperative computed tomography (CT) volume to the X-ray image. This allows the position of the implant to be calculated with respect to a CT-based surgical plan.

Validation of PET imaging by alignment to histology slices.

The aim of this project is to verify the accuracy of positron emission tomography (PET) in identifying the tumour boundary and eventually to enable PET-guided resection with removal of significantly smaller margins. We present a novel use of an image-guided surgery system to enable alignment of preoperative PET images to postoperative histology. The oral cancer patients must have a high resolution CT scan as well as undergoing PET imaging.

Self-calibrating ultrasound-to-CT bone registration.

We describe a new self-calibrating approach to rigid registration of 3D ultrasound images in which in vivo data acquired for registration are used to simultaneously perform a patient-specific update of the calibration parameters of the 3D ultrasound system. Using a self-calibrating implementation of a point-based registration algorithm, and points obtained from ultrasound images of the femurs and pelves of human cadavers, we show that the accuracy of registration to a CT scan is significantly improved compared with a standard algorithm. This new approach provides an effective means of compensating for errors introduced by the propagation of ultrasound through soft tissue, which currently limit the accuracy of conventional methods where the calibration parameters are fixed to values determined preoperatively using a phantom.

Self-calibrating 3D-ultrasound-based bone registration for minimally invasive orthopedic surgery.

Intraoperative freehand three-dimensional (3-D) ultrasound (3D-US) has been proposed as a noninvasive method for registering bones to a preoperative computed tomography image or computer-generated bone model during computer-aided orthopedic surgery (CAOS). In this technique, an US probe is tracked by a 3-D position sensor and acts as a percutaneous device for localizing the bone surface. However, variations in the acoustic properties of soft tissue, such as the average speed of sound, can introduce significant errors in the bone depth estimated from US images, which limits registration accuracy.

Registration and tracking to integrate X-ray and MR images in an XMR facility.

We describe a registration and tracking technique to integrate cardiac X-ray images and cardiac magnetic resonance (MR) images acquired from a combined X-ray and MR interventional suite (XMR). Optical tracking is used to determine the transformation matrices relating MR image coordinates and X-ray image coordinates. Calibration of X-ray projection geometry and tracking of the X-ray C-arm and table enable three-dimensional (3-D) reconstruction of vessel centerlines and catheters from bi-plane X-ray views.

Civilian infratentorial gunshot injuries: outcome analysis of 26 patients.

Background: Craniocerebral missile injuries have steadily increased to become the most common form of penetrating neurotrauma in our environment resulting in continued morbidity and neuropsychological sequelae. Civilian infratentorial gunshot injuries are uncommon but generally regarded as fatal injuries, with many patients dying before reaching hospital.

Methods: A retrospective analysis of 1,069 patients with civilian gunshot wounds (GSW), admitted to our unit over a 14-year period (1986-2000), identified 26 patients with infratentorial gunshot injuries (2.