Graduation thesis article 1 February 10, 2012, Delft, Netherlands IN-VITRO AND CLINICAL MORCELLATOR FUNCTIONALITY ASSESSMENT Ewout A. Arkenbout, Just L. Herder ∗ Department of Biomedical Engineering Delft University of Technology Mekelweg 2, 2628 CD Delft The Netherlands Email: ewoutarkenbout@gmail.com Email: j.l.herder@tudelft.nl Andreas Thurkow Minimally Invasive Surgery Sint Lucas Andreas Hospital Jan Tooropstraat 164, 1061 AE Amsterdam The Netherlands Email: a.thurkow@slaz.nl Frank Willem Jansen Minimally Invasive Surgery Leiden University Medical Center Albinusdreef 2, 2333 ZA Leiden The Netherlands Email: f.w.jansen@lumc.nl ABSTRACT Morcellator functionality information is relatively limited in literature and mainly restricted to general clinical data. No spe- cific parameters related to morcellator working principles have been reported, making a surgeons choice to use a specific device mostly based on past experience and potential risks vs. benefits. Gaining insight into the morcellation time, morcellator speed, the number of tissue strips removed at a certain uterus weight and the amount of debris created by the morcellation process, can aid in the assessment of the procedure. This research eval- uates these criteria both in-vitro and in clinical practice for a morcellator based on the electromechanical tissue peeling prin- ciple. Additionally, time-action analyses are performed to gain insight into the time division of the separate phases inherent to the morcellation procedure. Concluded is that the morcellation rates found in-vitro and from gynaecological procedures are dif- ferent, but still allow for working principle comparison and in- sight into the functional speed of the instrument combined with the surgeons experience. Morcellation speed is found to increase with larger uteri, showing better instrument functioning speed at larger tissue masses. Time gained with respect to optimal func- tioning of the instrument is offset by time lost due to longer in- spection and irrigation time necessary for debris removal after the morcellation procedure. Time-action analyses show an ap- proximate 80% downtime of the morcellator both in test setup and in clinical practice, displaying the room for improvement of the instrument. ∗ Address all correspondence to this author. NOMENCLATURE IMR Instrument Morcellation Rate (g/min). Morcellator functioning speed determined from in-vitro obtained data. PMR Procedure Morcellation Rate (g/min). Morcellator func- tioning speed determined from data collected at hys- terectomy procedures involving morcellation. MCR Morcellator Cutting Rate (g/min). Effective morcellator cutting speed determined by excluding tissue manipula- tion and depositing phases in the morcellation process. f morce The sum of time spend morcellating and afterwards in- specting and irrigating the abdomen for debris, divided by the full procedure time. f 1−3 Time found for a specific time-action analysis phase (1- 3) divided by morcellation time. INTRODUCTION The use of a morcellator has become standard practice in gynaecology for the partial or total removal of the uterus at hys- terectomies. As such, various morcellators exist, as Miller dis- cussed in 2001 [1], and over the years several different work- ing principles have been used. In literature, these instruments have been mainly assessed on the basis of operation time, blood loss, recuperation time, and other general clinical parameters, but rarely is the morcellation procedure itself analyzed, and never have more than two morcellators been compared at the same time. For example, Erian et al. evaluated the difference be- tween the use of a reusable versus disposable electromechani- 1 Copyright c  2012 by BME, TU Delft