Percutaneous Radiofrequency Disc Decompression: A Study of 27 Patients.

BACKGROUND: Percutaneous radiofrequency nucleoplasty is a true minimally invasive technique for treatment for radiculopathy caused by contained disc protrusions. This minimally invasive procedure uses controlled thermoablation for reducing the intervertebral disc and decompressing the lumbar nerve root. Material and Methods: Our study is a prospective analysis of 27 patients aged from 30 to 64 years with lumbar disc protrusion who were treated with percutaneous radiofrequency disc decompression (PRFD) between May 2018 and May 2019. Clinical follow-up was reported at 1 month, 3 months, and 6 months. The outcomes were assessed using a visual analog scale (VAS) and MacNab score. RESULTS: Of the 27 patients, 14 were female and 13 were male. Their mean age was 53 ± 2 years. In all 27 patients, percutaneous radiofrequency nucleotomy was performed. An excellent outcome as reflected by MacNab score was observed in 17 patients (63%), a good outcome in 8 patients (29.7%), and a poor outcome in 2 patients (7.3%). Prior to treatment, the average back and leg VAS scores were 7.95 and 7.82, respectively. At sixth month follow-up, the back and leg VAS scores were reduced to 3.17 and 3.04, respectively. Patients with a poor outcome developed early recurrent disc prolapse and required endoscopic discectomy. CONCLUSION: PRFD is a safe and effective treatment of contained disc protrusion. PRFD is a good alternative to surgery. These procedures significantly increase quality of life in patients with lumbar radiculopathy.

Verification of the sampling procedure for radioactivity analysis of waste and industrial material.

In accordance with ISO/IEC 17025:2017, the testing laboratory needs to verify its ability to properly perform methods. For radiological testing, the sampling does not affect the results directly, but it has to ensure that sample adequately represents the tested material. To verify the procedure, a sampling of red mud and bauxite ore was conducted. All samples were measured in identical geometry by HPGe spectrometer. The counting rates per unit mass in the recorded spectra were compared. For each measurement series, the mean and standard deviations of respected peaks were calculated, as well as average and standard deviation of all series. The obtained results of each individual series were considered satisfactory, i.e. sampling procedure ensures the representativeness of the bulk material, if it is within ± two standard deviations of the average of the mean values.

The prognostic value of estimating stroke volume before and after exercise during treadmill stress echocardiography.

BACKGROUND: Stress echocardiography (SE) is an established technique for assessment of coronary artery disease (CAD) which is difficult to perform and interpret. Left ventricular stroke volume (SV) is readily estimated with Doppler echocardiography. It can be affected by myocardial ischemia, with possible adjunctive value during SE. METHODS: Patients underwent Bruce protocol SE with SV estimated before and after maximal treadmill exertion post routine regional wall analysis. Incremental change in SV (ΔSV) with exercise was measured. RESULTS: A derivation cohort (n = 273) was established to test the hypothesis. An optimal cutoff for detection on inducible ischemia was ΔSV ≤ +10 mL. The validation cohort of consecutive patients (n = 1093, 376 [34%] female; age 59 ± 12 years) were followed clinically after SE for 20 460 patient-months. There were 1000 patients with nonischemic SE, and 93 patients with studies suggestive of myocardial ischemia. Secondary analysis yielded 831 patients with a normal exercise response (ΔSV > +10 mL) and 192 with an abnormal ΔSV ≤ +10 mL. Time to first combined adverse cardiac event (composite of angina, acute coronary syndrome, cardiac revascularization, worsening New York Heart Association (NYHA) class, a reduction in EF, and cardiovascular death) was analyzed and adjusted using Cox proportional hazards regression. The hazard ratio for an adverse event with an abnormal ΔSV response (≤10 mL) was 10.3 (95% confidence intervals 5.6-19.1, P < .0001). CONCLUSIONS: Stroke volume assessment during SE is feasible and readily performed. It is simple, practical, and has incremental diagnostic and prognostic value when added to exercise regional wall-motion analysis.