Intra-articular psoas tendon release alters fluid flow during hip arthroscopy.

While not proven definitively, the hypothesis that intra-articular psoas tendon release allows fluid to track into the retroperitoneal space has been widely accepted. This study attempts to identify the path through which fluid enters the pelvis and retroperitoneal space. Six hemi-pelvis human cadaveric specimens were utilized for this study. 3 specimens underwent a capsulotomy and psoas tendon release, while 3 had only a capsulotomy. Arthroscopy fluid was combined with Barium and Methylene blue, and fluid was run at 50 mmHg for 2 hours. A gross dissection was performed at the end of the arthroscopy and the path of fluid flow into the pelvis and throughout the thigh was identified. All 6 specimens showed extravasation of fluid into the pelvis at the 5 minute mark. Specimens with a psoas tendon release showed an altered pattern of fluid flow. In all three of these specimens, the psoas muscle belly was bright blue, along with the remaining tendon. Two of the 3 specimens showed tracking of fluid along the vasculature in both directions. The volume of fluid tracking into the pelvis was increased following a psoas release. Arthroscopy fluid rapidly enters the pelvis following the initiation of hip arthroscopy, regardless of the status of the psoas tendon. Release of the psoas tendon allows fluid to diffuse into the psoas muscle and anterior medial thigh, tracking both proximally and distally along the neurovascular structures, and the volume of fluid tracking into the pelvis is increased following a psoas release.

Passivity test of Mueller matrices in the presence of additive Gaussian noise.

It is possible to introduce tolerancing with the realizability test of Givens and Kostinski [J. Mod. Opt.40, 471 (1993)] with a minor modification: it suffices to add a special matrix to [G][M](T)[G][M]. Consequently, it is possible to check experimental Mueller matrices with a more flexible tool. Application to the emblematic case of the Mueller images of the free space shows that more than 99% of the pixels are in fact physical, while only 2% initially passed the test.

Directional effects consideration to improve out-doors emissivity retrieval in the 3-13 mum domain.

This work analyses and solves for issues encountered when retrieving surface emissivity in LWIR (750 to 1250 cm(-1)) and MWIR (2000 to 3500 cm(-1)) bands under outdoor conditions. The Spectral Smoothness method, which takes advantage of high spectral resolution measurements to solve for temperature emissivity separation, and which has already proven its efficiency in the LWIR domain, was applied in an experimental campaign to assess its ability to operate both in the LWIR and MWIR domains. In the MWIR band, directional behaviour of surface emissivity is shown to be a source of systematic errors in the retrieved emissivity and a new method, called SmaC (SMoothness And Continuity), corrects for this error by providing quantitative estimates on the deviation of the surface from Lambertian behavior.

Multi temporal regression method for mid infrared [3-5microm] emissivity outdoor.

An experimental study to address issues encountered in the determination of surface bi-directional reflectivity and emissivity of materials [3-5microm] region has been conducted in outdoors conditions. The measurement protocol included radiometric infrared camera acquisitions in both [3-5microm] (band-2) and [8-14microm] (band-3). The band-2 bi-directional reflectivity is obtained from a sequence of sunlit and shade measurements. Best results are found with measurements relative to a diffuse aluminum reflector. Direct inversion of band-2 radiometric signal is unstable. A multitemporal method is introduced and the slope of the linear regression is the searched emisssivity. A detailed analysis is conducted to assess the impact of different sources of systematic errors. The proposed method is found to have a good potential with an estimated measurement error in the range of 2%.