title: EFFECTS OF A MODIFIED VITRECTOMY PROBE IN SMALL-GAUGE VITRECTOMY: An Experimental Study on the Flow and on the Traction Exerted on the Retina.
abstract: OBJECTIVE
  Thorough this experimental study, the physic features of a modified 23-gauge vitrectomy probe were evaluated in vitro.
  
  
  METHODS
  A modified vitrectomy probe to increase vitreous outflow rate with a small-diameter probe, that also minimized tractional forces on the retina, was created and tested. The "new" probe was created by drilling an opening into the inner duct of a traditional 23-gauge probe with electrochemical or electrodischarge micromachining. Both vitreous outflow and tractional forces on the retina were examined using experimental models of vitreous surgery.
  
  
  RESULTS
  The additional opening allowed the modified probe to have a cutting rate of 5,000 cuts per minute, while sustaining an outflow approximately 45% higher than in conventional 23-gauge probes. The modified probe performed two cutting actions per cycle, not one, as in standard probes. Because tractional force is influenced by cutting rate, retinal forces were 2.2 times lower than those observed with traditional cutters.
  
  
  CONCLUSIONS
  The modified probe could be useful in vitreoretinal surgery. It allows for faster vitreous removal while minimizing tractional forces on the retina. Moreover, any available probe can be modified by creating a hole in the inner duct.
authors.affiliation: *Azienda Ospedaliero-Universitaria Careggi, Florence, Italy; †Department of Civil and Industrial, Engineering University, Pisa, Italy; ‡Centro E. Piaggio, Engineering University of Pisa, Pisa, Italy; §Erre Quadro s.r.l., Pisa, Italy; ¶Doheny Eye Institute, Los Angeles, California; **Azienda Ospedaliero-Universitaria Cisanello, Pisa, Italy; ††Federal University of Sao Paulo, Sao Paulo, Brazil; and ‡‡Ospedale Oftalmico di Torino, Turin, Italy.
authors.forename: Stanislao
authors.initials: S
authors.lastname: Rizzo
authors.forename: Gualtiero
authors.initials: G
authors.lastname: Fantoni
authors.forename: Giovanni
authors.initials: G
authors.lastname: de Santis
authors.forename: Jaw-Chyng Lormen
authors.initials: JL
authors.lastname: Lue
authors.forename: Jonathan
authors.initials: J
authors.lastname: Ciampi
authors.forename: Michele
authors.initials: M
authors.lastname: Palla
authors.forename: Federica
authors.initials: F
authors.lastname: Genovesi Ebert
authors.forename: Alfonso
authors.initials: A
authors.lastname: Savastano
authors.forename: Carmelo
authors.initials: C
authors.lastname: De Maria
authors.forename: Giovanni
authors.initials: G
authors.lastname: Vozzi
authors.forename: Rodrigo A
authors.initials: RA
authors.lastname: Brant Fernandes
authors.forename: Francesco
authors.initials: F
authors.lastname: Faraldi
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Criscenti
mesh_terms: D006801:Humans; D008866:Microsurgery / Q000295:instrumentation; D012160:Retina / Q000502:physiology*; D013314:Stress, Mechanical; D014143:Traction; D014821:Vitrectomy / Q000295:instrumentation* / Q000379:methods*; D014822:Vitreous Body / Q000378:metabolism*