THREE-DIMENSIONAL RETINAL DISPLACEMENT BEFORE AND AFTER MACULAR PUCKER SURGERY.

PURPOSE: To measure the coronal and sagittal retinal displacement before and after surgery for epiretinal membranes in InfraRed horizontal foveal sections and optical coherence tomography scans and describe displacement tridimensionality, vision loss, and metamorphopsia. METHODS: Retrospective series with greater than 6-month average follow-up before and after surgery. The record included best-corrected visual acuity, optical coherence tomography, M-charts, and InfraRed retinography. Overall, pre- and postoperative coronal and sagittal retinal displacement across the entire field, concentric circles at 0.5-, 1.5-, and 4.5-mm radii, and the central horizontal and vertical meridian were calculated as the optical flow of consecutive images. RESULTS: This study comprised 10 patients (4 men, 6 women), with 22.7 ± 25.2 months follow-up before surgery and 16.2 ± 7.3 months after. Best-corrected visual acuity reduced before surgery (0.15 ± 0.67 logarithm of minimum angle of resolution to 0.38 ± 0.85 logarithm of minimum angle of resolution; P < 0.05) and increased afterward (0.086 ± 0.61 logarithm of minimum angle of resolution; P = 0.003). Preoperative coronal displacement was 30.1 ± 29.1 µm versus 67.0 ± 23.4 µm after (P = 0.002). Sagittal retinal displacement was 140.9 ± 84.6 µm before surgery, 339.7 ± 172.5 µm after (P = 0.017), and 357.6 ± 320.8 µm across the entire follow-up. Preoperative best-corrected visual acuity decreases correlated with the foveal coronal displacement. Vertical metamorphopsia correlated with the average coronal displacement within a 4.5-mm radius. Pre- and postoperative sagittal displacement correlated with horizontal metamorphopsia (P = 0.006 and P = 0.026). Postoperative sagittal displacement correlated with postoperative best-corrected visual acuity (P = 0.026) and foveal thickness (P = 0.009). CONCLUSION: This study confirms that postoperative displacement is greater than preoperative and that sagittal displacement is greater than coronal and correlates with best-corrected visual acuity and metamorphopsia changes.

Gastric band removal: mind the arterial anastomoses!

Bariatric surgery may sometimes be challenging and may lead to severe complications. Surgical re-intervention in such cases is not the preferred option due to co-morbidities. When severe bleeding occurs, embolization of the lacerated vessels is the preferred minimal invasive management option and needs to be available if possible. We would like to report a case of young patient who underwent severe bleeding after migration of a gastric band. The patient was successfully embolized and the band was removed. However, on the second post-operative day, the patient complained again for acute abdominal pain and turned haemodynamically unstable. Fresh blood was aspirated from the surgical drain. A new emergency CT scan was performed and a new large pseudoaneurysm was revealed taking origin from the left gastric artery. The second bleeding occurred due to an anastomotic communication and was also successfully embolized. The main take home messages are that bariatric surgery may lead to several complications including bleeding, gastric band may cause vessel erosion but also offer a tamponade effect, endovascular embolization of the lacerated vessels is the preferred management and pseudoaneurysms arising in hepato-splenic or gastroduodenal arteries should be treated with the sandwich embolization technique.

Evaluation of the point sampling method and inter-comparison of remote emission sensing systems for screening real-world car emissions.

Emissions from internal combustion vehicles are currently not properly monitored throughout their life cycle. Remote emission sensing (RES) is a technology that can measure emissions under real driving conditions without contact. Current light extinction based RES systems are capable of providing emission factors for various gases, but lack accuracy for particulate matter (PM). Point Sampling (PS) is an extraction-based RES technique that can measure gases as well as various particle metrics such as black carbon or particle number. In this work, we evaluated the performance of a recently developed PS system and the state-of-the-art light extinction based remote sensing devices EDAR (HEAT) and ORSD (OPUS RSE) during co-location measurements. Validation measurements with portable emission measurement systems and emissions screening of several thousand cars in three European cities provide detailed insights into system's performance. Meteorological evaluations showed that the PS capture rate is strongly influenced by wind, but no other weather influences were found. Both light extinction based systems are unable to measure during rain. We found that all three systems tested were capable of screening NOx emissions from pre-Euro 6 diesel cars. Measurement results show the ability of the PS system to quantify high and low PM emitters equally well. The open-path RES systems (EDAR, ORSD) are capable of estimating PM emissions from pre-Euro 5 diesel cars. However, deficiencies of open-path RES systems are evident in the quantification of PM emissions from newer engine technologies (diesel Euro 5 and beyond) and from petrol cars. The PS system has a 2 to 5 times lower capture rate than open-path RES systems, but the PS measurement results are more accurate (more than 5 times for PM and more than 1.35 times for NOx). The good accuracy of individual measurements makes PS a powerful tool for reliable high emitter identification.