title: Comparison of reaction response time between hand and foot controlled devices in simulated microsurgical testing.
abstract: OBJECTIVE
  We hypothesized that reaction times (RTs) for a switch release are faster for hand-controlled than for foot-controlled switches for physiological and anatomical reasons (e.g., nerve conduction speed). The risk of accidental trauma could be reduced if the surgeon reacted quicker and therefore improve the surgical outcome.
  
  
  METHODS
  We included 47 medical professionals at USC. Demographics and handedness were recorded. Under a microscope, a simple reaction time test was performed, testing all extremities multiple times in a random order. Additionally, a subjective questionnaire was administered.
  
  
  RESULTS
  The mean RTs for hands are 318.24 ms ± 51.13 and feet 328.69 ± 48.70. The comparison of hand versus foot showed significant shorter RTs for the hand (P = 0.025). Partially significant differences between and within the experience level groups could be demonstrated by level of education (LE) and microscopic surgeries/week (MSW) (P = 0.57-0.02). In the subjective questionnaire, 91.5% (n = 43/47) of test subjects prefer to use hand controls.
  
  
  CONCLUSIONS
  Our data show that the RT for hands is faster than feet. Similarly the subjective questionnaire showed a greater preference for hand actuation. This data suggest a hand-controlled ophthalmic instrument might have distinct advantages; however, clinical correlation is required.
authors.affiliation: Doheny Eye Institute, 1450 San Pablo Street, Los Angeles, CA 90033, USA ; Department of Ophthalmology, Keck School of Medicine, University of Southern California, 1450 San Pablo Street, Los Angeles, CA 90033, USA.
authors.forename: Marcel
authors.initials: M
authors.lastname: Pfister
authors.affiliation: Doheny Eye Institute, 1450 San Pablo Street, Los Angeles, CA 90033, USA.
authors.forename: Jaw-Chyng L
authors.initials: JC
authors.lastname: Lue
authors.affiliation: Doheny Eye Institute, 1450 San Pablo Street, Los Angeles, CA 90033, USA ; Department of Ophthalmology, Keck School of Medicine, University of Southern California, 1450 San Pablo Street, Los Angeles, CA 90033, USA ; Department of Ophthalmology and Visual Sciences, Federal University of Sao Paulo (UNIFESP), Rua Botucatu, No. 740, 04023-900 Sao Paulo, SP, Brazil.
authors.forename: Francisco R
authors.initials: FR
authors.lastname: Stefanini
authors.affiliation: Doheny Eye Institute, 1450 San Pablo Street, Los Angeles, CA 90033, USA ; Department of Ophthalmology, Keck School of Medicine, University of Southern California, 1450 San Pablo Street, Los Angeles, CA 90033, USA ; Department of Ophthalmology and Visual Sciences, Federal University of Sao Paulo (UNIFESP), Rua Botucatu, No. 740, 04023-900 Sao Paulo, SP, Brazil.
authors.forename: Paulo
authors.identifier: 0000-0001-8773-7168
authors.initials: P
authors.lastname: Falabella
authors.affiliation: Department of Preventive Medicine, University of Southern California, 1975 Zonal Avenue, Los Angeles, CA 90089, USA.
authors.forename: Laurie
authors.initials: L
authors.lastname: Dustin
authors.affiliation: Doheny Eye Institute, 1450 San Pablo Street, Los Angeles, CA 90033, USA ; Department of Ophthalmology, Keck School of Medicine, University of Southern California, 1450 San Pablo Street, Los Angeles, CA 90033, USA ; Department of Ophthalmology, Ruprecht-Karls-University, Grabengasse 1, 69117 Heidelberg, Germany.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Koss
authors.affiliation: Department of Ophthalmology, Keck School of Medicine, University of Southern California, 1450 San Pablo Street, Los Angeles, CA 90033, USA.
authors.forename: Mark S
authors.initials: MS
authors.lastname: Humayun
mesh_terms: D000328:Adult; D005260:Female; D005528:Foot / Q000502:physiology; D006225:Hand / Q000502:physiology; D006801:Humans; D008297:Male; D013508:Ophthalmologic Surgical Procedures / Q000592:standards*; D011930:Reaction Time / Q000502:physiology*; D013337:Students, Medical; D066231:Surgeons; D011795:Surveys and Questionnaires