Visual Spatial Ability – Are Surgeons Born or Made?

Zackary Boom-Saad, Pamela Andreatta, EdD, Miranda L. Hillard, Anthony G. Gallagher, PhD†, Scott Langenecker, PhD, Angela Caveny, PhD,

Paul G. Gauger, MD, and Rebecca M. Minter, MD

University of Michigan and Royal College of Surgeons in Ireland†

Background

• “…ultimately the level of surgical technical performance at the end of training that an individual can achieve is determined by…innate ability…”1

• “…advanced trainees and experts do not score higher on carefully selected visual-spatial tests, suggesting that practice and surgical experience may supplant the influence of visual-spatial ability over time…”2

1 MacMillan et al. Am Jour Surg 1999.:177: 274-2772 Wanzel et al. Surgery 2003:134: 750-7

Hypothesis

No significant baseline differences in visual-spatial, psychomotor, and minimally invasive surgical skills exist between students entering procedural and non-procedural fields.

Methodology: Protocol

Thirty M4s

Procedural Group(n=17)

Non-procedural Group(n=13)

1. Visual-Spatial Ability and Psychomotor Testing2. PicSOr and LapSim Exercises

Comparison of Group Performance

Subject Demographics

• Procedural (n=17)– General surgery– Urology– Orthopaedics– Ophthalmology– Plastic surgery– ENT– Ob/Gyn

• Non-procedural (n=13)– Internal medicine– Pediatrics– Med/Peds– Anesthesiology– Radiation oncology– PM&R– Pathology– Emergency Medicine– Family medicine

Subject Demographics

Procedural: Non-Procedural:

Gender Male 14 5 Female 3 8 Handedness Right 16 13 Left 1 0 Video game experience: Prior 11/17 6/13 Current 6/17 4/13

Mental Rotations Test

Surface Development Test

Put picture here

CANTAB

• Cambridge Neuropsychological Test Automated Battery

• Three component assessments– Procedural learning and visual memory– Rapid visual information processing– Motor dexterity and reaction time

PicSOr

• Tests subject’s ability to discern orientation of a 3-D object shown in two-dimensions1

1 Gallagher et al. Surg Endosc 2003; 17: 168-71

LapSim™

• Virtual reality laparoscopic simulator

• Built-in metrics with established construct validity

• Performance on five basic skills tasks assessed

Statistical Analysis

• ANOVA for differences between groups on LapSim

• t-tests for MRT, CANTAB, SDT, and PicSOr

• Pearson correlation coefficient between PicSOr and LapSim

Results: MRT and SDTM

RT

Sco

re

0

5

10

15

20

25

30

35

Procedural Non-Procedural

SD

T S

core

0

10

20

30

40

50

60

Procedural Non-Procedural

Results: CANTAB

Procedural

(Mean±SD)

Non-procedural

(Mean±SD)

Significance

Procedural learning

Stages completed 1st trial

Mean errors to succes

Total errors (adjusted)

3.93±0.73

0.64±0.85

3.21±4.25

3.69±0.75

0.85±0.73

4.23±3.63

p=0.42

p=0.51

p=0.51

Rapid visual processing

Mean latency

Probability of false alarm

Probability of hit

392±47

0.003±0.006

0.89±0.07

394±39

0.001±0.003

0.84±0.11

p=0.88

p=0.29

p=0.15

Reaction time

5-ch movement time

5-ch reaction time

327±75

312±36

377±105

315±50

p=0.17

p=0.19

Results – PicSOr

Correlation Coefficient (Mean±SD)

Procedural students 0.93 ± 0.04*

Non-procedural students 0.82 ± 0.12 *p<0.01

Results – LapSim™

Procedural

(Mean±SD)

Non-procedural

(Mean±SD)

Significance

(p value)

Grasping

L instr time

L instr misses

L instr path length

L instr ang path

R instr time

R instr ang path

Max damage

47.26±9.71

0.90±1.10

2.16±0.44

454.79±69.29

37.78±7.00

372.20±65.57

4.34±1.78

59.42±13.74

5.77±7.19

2.73±0.71

581.41±186.14

48.41±9.52

486.95±122.17

8.83±6.71

0.016

0.024

0.022

0.031

0.003

0.006

0.029

Results – LapSim

Procedural

(Mean±SD)

Non-procedural

(Mean±SD)

Significance

(p value)

Lifting and Grasping Time

L instr path length

L instr ang path

R instr path length

R instr ang path

56.10 ±16.01

1.63 ±0.31

441.04±70.50

1.63±0.29

362.31±47.83

68.03±10.22

1.98±0.41

517.66±104

1.96±0.35

424.63±61.18

0.038

0.024

0.040

0.016

0.009

Clip Applying Blood loss 0.12±0.05 0.21±0.14 0.044

Performance Correlation – PicSOr and LapSim

• Coordination– 6/8 parameters, p<0.05

• Grasping– 7/11 parameters, p<0.05

• Lifting and Grasping – 8/10 parameters, p<0.05

• Clip Applying– 6/9 parameters, p<0.05

Summary

• No significant difference between groups– Visual spatial ability– Pyschomotor ability

• Procedural students demonstrate a higher baseline performance level with respect to minimally invasive surgical skills– PicSOr performance– LapSim performance

Conclusions

• Are surgeons born or made?– Differences in laparoscopic performance exist

and can be measured– Creates possibility of performing an early

needs assessment, and the ability to develop individualized curricula for MIS skills training

• Can individuals be trained to equivalent performance levels with focused instruction?

Limitations

• Small sample size– Type II error

– Inability to stratify by specialty

• Laparoscopic performance assessment was based only on simulated exercises, not on actual intra-operative performance

Acknowledgements

• Association for Surgical Education Foundation – Center for Excellence in Surgical Education, Research, and Training (CESERT)

• United States Surgical Corporation