Percutaneous retrogasserian glycerol rhizotomy for trigeminal neuralgia: an alternative technique.

One of the challenges faced by the modern-day NHS is workplace shortages, and experienced radiographers for intra-operative neurosurgical imaging is one such scenario. We describe our method for Percutaneous Retrogasserian Glycerol Rhizotomy (PRGR) using frameless neuronavigation which can be used effectively in such scenarios. Stealth neuronavigation is used for needle placement within the foramen ovale and injection of glycerol, under sedation.

Emissions of organic compounds from produced water ponds III: Mass-transfer coefficients, composition-emission correlations, and contributions to regional emissions.

A common method for treating the aqueous phase (produced water) brought to the surface along with oil and natural gas is to discharge it into surface impoundments, also known as produced water ponds. Here we analyze data on the concentration of organic compounds in the water and on the flux of the same compounds into the atmosphere. Flux data extending from about 5 × 10 to 10 mg m h are consistent with mass-transfer laws given by the WATER9 semi-empirical algorithm, although empirical data display a noise level of about one order of magnitude and predictions by WATER9 are biased high.

Emissions of organic compounds from produced water ponds II: Evaluation of flux chamber measurements with inverse-modeling techniques.

Unlabelled: In this study, the authors apply two different dispersion models to evaluate flux chamber measurements of emissions of 58 organic compounds, including C2-C11 hydrocarbons and methanol, ethanol, and isopropanol from oil- and gas-produced water ponds in the Uintah Basin. Field measurement campaigns using the flux chamber technique were performed at a limited number of produced water ponds in the basin throughout 2013-2016. Inverse-modeling results showed significantly higher emissions than were measured by the flux chamber.