Evaluation of the ScopeControl endoscope test system in six hospitals in The Netherlands.

As rigid endoscopes are re-used after minimal invasive surgery, they degrade over time. To guarantee the optical quality of a rigid endoscope, the ScopeControl has been developed to measure key optical parameters such as, light transmission (LT), color correctness (CC), focus (FC), fiber transmission (FT), viewing angle (VA) and field of view (FV). To evaluate the performance of the ScopeControl, five ScopeControls SV (study version) have been tested in six hospitals in the Netherlands. Aspects such as robustness, precision, usability of the measured data, acceptation criteria and ergonomic aspects have been assessed. The ScopeControl maintains its stability over time and can measure LT, CC and FC with 5% precision, VA and FV with 2% accuracy and FT with 10% precision. The final thresholds above which an endoscope could still be considered to be in good condition, appeared to be: VA at 75%, CC, FC and FV at 70%, LT at 65% and FT at 35% of that of the best endoscope of that type ever found. The ScopeControl SV fits the workflow of the sterilization department as it is easy to use and can easily be cleaned. The time to perform a measurement is 2-3 min (one minute is spent to select the correct endoscope). The ScopeControl PV (launched in November 2013), has been used clinically from April to November 2014. It proves to be more stable, well accepted by personnel from the sterilization department and be of large value of preventing defect endoscopes on the surgery table.

Part 2: ultrastructural changes of fibrin networks during three phases of pregnancy: a qualitative investigation.

INTRODUCTION: Normal pregnancy is characterized by significant alterations in the haemostatic system accompanied by an augmented risk of thrombosis. MATERIALS AND METHODS: The fibrin network ultrastructure of different phases of pregnancy, namely early pregnancy (week 8-14), late pregnancy (week 36-40) as well as post-partum (week 6-8 after birth) were compared with nonpregnant fibrin networks as well as each other to establish whether differences in fibrin network morphology exist during pregnancy. Scanning electron microscopy was employed to analyse fibrin network morphology. RESULTS: The fibrin networks from all phases of pregnancy appeared similar to each other, exhibiting prominent coagulant formation, an increase in the formation of minor, thin fibers, and the presence of granular globules. All three phases, however, differ from the typical fibrin network ultrastructure exhibited by the fibrin networks from nonpregnant individuals. The increase in estrogen associated with pregnancy may cause the increase in coagulation factors and ultimately the prothrombotic state characteristic of pregnancy. CONCLUSIONS: Since no differences were apparent between the different phases of pregnancy it suggests that activation of the coagulation system commences with pregnancy and this pro-thrombotic state continues till at least 8 weeks after birth. These results may shed light on possible pathological mechanisms employed in the development of abnormal or ailing pregnancy.

Estrogen causes ultrastructural changes of fibrin networks during the menstrual cycle: a qualitative investigation.

INTRODUCTION: Hormonal fluctuations may influence fibrin structure. During the menstrual cycle, plasma fibrinogen levels change, mainly due to the variations of estrogen. Throughout the menstrual cycle estrogen levels peak twice, first during the mid-follicular phase and then a lower second peak during the luteal phase. MATERIALS AND METHODS: In order to investigate the possible changes in the fibrin network throughout the menstrual cycle, the fibrin network ultrastructure of six healthy female participants were studied at different intervals in the menstrual cycle where differences in estrogen levels are prevalent. Blood plasma smears were prepared for scanning and transmission electron microscopy analysis. RESULTS: The external and internal structure of the fibrin fibers showed different morphologies throughout the menstrual cycle. The fibrin fibers were smooth during days 1-5. However, during days 12-14 of the menstrual cycle the fibrin fiber morphology started to change, becoming less smooth. During the luteal phase of the cycle (days 20-25), the network appears sticky, where the minor, thin fibers are more prominent between the thick fibers when compared to the menstrual phase. CONCLUSION: The two estrogen peaks of the menstrual cycle coincide with the changes seen in the current qualitative research, where the fibrin morphology changes during the same time as the estrogen peaks occur. Purified fibrinogen confirmed that it is indeed estrogen that causes the altered fibrin network morphology. This research is the first to show ultrastructural changes in fibrin fiber morphology resulting from estrogen changes during the menstrual cycle.