Marisa Louridas

July 2017

  • PGY4
  • Residency Program: University of Toronto
  • Supervisors: Dr. Teodor Grantcharov,


Marisa Louridas obtained both her undergraduate degree in genetics as well as her Medical Doctorate from the University of Manitoba. She is currently a General Surgery resident at the University of Toronto.  As part of her postgraduate training, she completed her PhD at the Institute of Medical Science under the auspices of the University of Toronto Surgeon Scientist Training Program, and participated in the Royal College Clinical Investigator Program under the mentorship of Dr. Teodor Grantcharov.

Her research interests are in surgical education. More specifically, she is interested strategies to improve acquisition of technical skill in surgical residents, ranging from screening for technical ability at the time of selection, to incorporating performance adjuncts into surgical training. Marisa has had the privilege of presenting her research at national and international conferences, and has more than 15 peer reviewed publications.

Her PhD was supported by the Queen Elizabeth II/William K. Kerr Scholarship in Science and Technology, and by the Royal College of Physicians and Surgeons of Canada H.S. Morton Fund. In 2016 she received the Gallie Bateman Award for best oral presentation from the Department of Surgery, University of Toronto.


Research Summary

Evidence suggests that not all surgical trainees reach technical competence. Therefore the purposes of these studies were to improve resident selection by investigating screening tools (visual spatial tests (VSTs) and technical tasks (TTs)) that may predict technical ability of incoming trainees, and to determine whether metal practice is beneficial as a performance enhancement strategy during training.

Screening with VSTs as a predictor of laparoscopic ability was evaluated using the PicSOr, cube comparison (CC) and card rotation (CR) tests and correlated to technical performance on the camera navigation (LCN) and laparoscopic circle cut (LCC) tasks. To screen trainees using TTs, a Delphi of Canadian general surgery (GS) program directors (PD), was performed to gain consensus on the simulated TTs best suited for incoming trainees. K-mean clustering learning curve (LC) analysis was used to determine acquisition of TTs. Next, mental practice was evaluated in a randomized control trial to assess its impact on advanced laparoscopic technical performance.

Thirty-seven residents were screened using VSTs. Residents who scored higher on the CC test had more accurate LCN path length (rs(PL) =-0.36, p=0.03) and angle path (rs(AP) =-0.426, p=0.01) scores. Eleven of 14 GS PDs participated in the Delphi, and consensus was reached that both basic laparoscopic and open skills would be appropriate for the assessment of TTs. LC analysis of 65 students revealed that 7-15% of trainees did not reach proficiency in laparoscopic skills. These students demonstrated poor innate ability, and remained disadvantaged with inconsistent performance throughout their LC. During training, mental practice significantly improved technical performance (p =0.003).

LC analysis of simulated technical skills proved more dependable than VSTs to screen for technical ability in novice trainees, while mental practice is an affective adjunct to technical skills performance and would be a beneficial addition to skills training for senior residents.