Predicting lamb carcase composition from tissue depth measured at a single point with an ultrawide-band microwave scanner

This study evaluated the ability of portable ultra-wide band microwave system (MiS) to predict lamb carcase computed tomography (CT) determined composition % of fat, lean muscle and bone. Lamb carcases (n = 343) from 6 slaughter groups were MiS scanned at the C-site (45 mm from spine midline at the 12th /13th rib) prior to CT scanning to determine the proportion of fat, muscle and bone. A machine learning ensemble stacking technique was used to construct the MiS prediction equations. Predictions were pooled and divided in 5 groups stratified for each CT composition trait (fat, lean or bone%) and a k-fold cross validation (k = 5) technique was used to test the predictions. MiS predicted CT fat% with an average RMSEP of 2.385, R2 0.78, bias 0.156 and slope 0.095. The prediction of CT lean% had an average RMSEP of 2.146, R2 0.64, bias 0.172 and slope 0.117. CT bone% prediction had an average RMSEP of 0.990, R2 0.75, bias 0.051 and slope 0.090. Predictions for CT bone% met AUS-MEAT device accreditation error tolerances on the whole range of the dataset. Predictions for CT lean% and fat% met AUS-MEAT error tolerances on a constrained dataset.

Outpatient argon laser iridectomy for angle closure glaucoma: a two-year study

A technique for iridectomy in the the treatment of angle-closure glaucoma utilizing laser beams has been developed. The operation is performed in two steps. In step 1 a partially penetrating burn of the iris is made to produce an iris hump. In step 2 a penetrating burn is used to pierce the crown of the previously produced hump. Tables 1, 2, and 3 summarize current recommendations and the detailed steps that must be followed (without exception) to achieve success with this technique. Of 22 phakic eyes, fellow eyes, or eyes with narrow-angle glaucoma, instantaneous, permanent iris perforation was produced in all except two. In these two, a second treatment on the following day produced a permanent perforation. Serious complications were encountered in only one patient who received treatment at a greater energy level than we now recommend. In that patient striate keratopathy became apparent, as well as a decrease in vision which has lasted five months. No significant complication was encountered in any eye treated with the currently recommended procedure.