Distribution of amyloid precursor protein and amyloid-beta in ocular hypertensive C57BL/6 mouse eyes

Amyloid precursor protein (APP) and amyloid-beta (Abeta) appear to participate in the pathophysiology of retinal ganglion cell (RGC) death in glaucoma. We, therefore, determined the distribution of APP and Abeta in the retinas of C57BL/6 mice after induction of chronic ocular hypertension.

The ocular pulse amplitude at different intraocular pressure: a prospective study

To investigate changes in ocular pulse amplitude (OPA) during a short-term increase in intraocular pressure (IOP) and to assess possible influences of biometrical properties of the eye, including central corneal thickness (CCT) and axial length.

How should bladder wall thickness be measured? A comparison of vaginal, perineal and abdominal ultrasound

Measurement of bladder wall thickness using transvaginal ultrasound has previously been shown to discriminate between women with diagnosed detrusor overactivity and those with urodynamic stress incontinence. So far, no comparison has been made between abdominal, perineal and vaginal route for the measurement of bladder wall thickness. The aim of this prospective study was to determine if abdominal, perineal and vaginal ultrasound measurements of bladder wall thickness are comparable with each other.

A study of progress of labour using intrapartum translabial ultrasound, assessing head station, direction, and angle of descent

Intrapartum translabial ultrasound (ITU) has the potential to objectively and quantitatively assess the progress of labour. The relationships between the different ITU parameters and their development during normal term labour have not been studied.

Reproducibility of sensory nerve conduction studies of the sural nerve using ultrasound-guided needle positioning

In this study we sought to evaluate the reproducibility of sensory nerve conduction studies (NCS) using ultrasound-guided needle positioning (USNP).

A shortened radiofrequency denervation method for cervical zygapophysial joint pain based on ultrasound localization of the nerves

Radiofrequency neurotomy is a recognized treatment for cervical zygapophysial joint pain. In several studies, the method has provided complete pain relief in 60-70% of the patients for approximately 9 months. The validated technique has the disadvantage of procedural times of 2-4 hours because several lesions are performed to take into account the variable nerve course. We tested the hypothesis that ultrasound localization of the nerves would enable us to reduce the number of lesions performed, while reaching the benchmark of at least 80% pain relief in 80% of patients with a median duration of 35 weeks, as achieved by a previous investigation using the standard method.

Ultrasound anatomy of the nerves supplying the cervical zygapophyseal joints: an exploratory study

Nerve blocks and radiofrequency neurotomy of the nerves supplying the cervical zygapophyseal joints are validated tools for diagnosis and treatment of chronic neck pain, respectively. Unlike fluoroscopy, ultrasound may allow visualization of the target nerves, thereby potentially improving diagnostic accuracy and therapeutic efficacy of the procedures. The aims of this exploratory study were to determine the ultrasound visibility of the target nerves in chronic neck pain patients and to describe the variability of their course in relation to the fluoroscopically used bony landmarks.

Evaluation of a novel needle guide for ultrasound-guided phantom vessel cannulation

We evaluated a novel, sled-mounted needle guide for ultrasound-guided vessel cannulation. Fifty medical students were randomly assigned to use ultrasound with the sled (sled group, n = 23) or ultrasound without the sled (control group, n = 27) for vessel cannulation in a phantom. For each of 15 attempts we recorded cannulation time and designated a successful cannulation as 1 and a failure as 0. Our primary outcome was the mean overall success rate. The median (IQR [range]) number of successes in the sled group and control group were 15.0 (13.0-15.0 [11.0-15.0]) and 11.0 (9.0-13.0 [6.0-15.0]), respectively (p < 0.001). Cannulation time decreased from the first to the last attempt in the sled group from 7.0 s (6.0-10.0 [4.0-16]) s to 4.0 s (3.0-4.0 [1.0-6.0]) s and in the control group from 35.0 s (27.0-35.0 [11.0-35.0]) s to 7.0 s (5.0-10.0 [3.0-25.0]) s. The sled group demonstrated a shorter cannulation time at each attempt (p < 0.001). The novel sled improved the success rate and efficiency of ultrasound-guided phantom vessel cannulation.

Ultrasound-guided percutaneous tracheal puncture: a computer-tomographic controlled study in cadavers

Ultrasound-guided techniques are increasingly used in anaesthetic practice to identify tissues beneath the skin and to increase the accuracy of placement of needles close to targeted structures. To examine ultrasound's usefulness for dilatational tracheostomy, we performed ultrasound-guided tracheal punctures in human cadavers followed by computer-tomographic (CT) control.

Different Learning Curves for Axillary Brachial Plexus Block: Ultrasound Guidance versus Nerve Stimulation

Little is known about the learning of the skills needed to perform ultrasound- or nerve stimulator-guided peripheral nerve blocks. The aim of this study was to compare the learning curves of residents trained in ultrasound guidance versus residents trained in nerve stimulation for axillary brachial plexus block. Ten residents with no previous experience with using ultrasound received ultrasound training and another ten residents with no previous experience with using nerve stimulation received nerve stimulation training. The novices' learning curves were generated by retrospective data analysis out of our electronic anaesthesia database. Individual success rates were pooled, and the institutional learning curve was calculated using a bootstrapping technique in combination with a Monte Carlo simulation procedure. The skills required to perform successful ultrasound-guided axillary brachial plexus block can be learnt faster and lead to a higher final success rate compared to nerve stimulator-guided axillary brachial plexus block.

Thin-Film Sparse Boundary Array Design for Passive Acoustic Mapping During Ultrasound Therapy

A new 2-D hydrophone array for ultrasound therapy monitoring is presented, along with a novel algorithm for passive acoustic mapping using a sparse weighted aperture. The array is constructed using existing polyvinylidene fluoride (PVDF) ultrasound sensor technology, and is utilized for its broadband characteristics and its high receive sensitivity. For most 2-D arrays, high-resolution imagery is desired, which requires a large aperture at the cost of a large number of elements. The proposed array's geometry is sparse, with elements only on the boundary of the rectangular aperture. The missing information from the interior is filled in using linear imaging techniques. After receiving acoustic emissions during ultrasound therapy, this algorithm applies an apodization to the sparse aperture to limit side lobes and then reconstructs acoustic activity with high spatiotemporal resolution. Experiments show verification of the theoretical point spread function, and cavitation maps in agar phantoms correspond closely to predicted areas, showing the validity of the array and methodology.