title: The Liss maneuver: a nonendoscopic technique for difficult Foley catheterization.
abstract: OBJECTIVE
  Difficult male catheterization often results in the need for bedside cystoscopy; herein, we describe a simple maneuver that may preclude the need for a more involved and expensive endoscopic procedure.
  
  
  METHODS
  A 0.035-inch Amplatz Super Stiff guidewire was placed floppy end first, down an 18F Foley catheter lumen; the guidewire was then clamped proximally to the body of the catheter at its point of exit. To test the added stiffness that the wire imparted to the tip and body of the catheter, different size Bardex I.C. Foley catheters were tested with a 0.035-inch 145-cm Amplatz Super Stiff guidewire placed in an Chattillon Force Gauge (TCM 201 Asset #4665) to measure bending force and tip strength in pounds of pressure.
  
  
  RESULTS
  The catheter body bending force (stiffness) was increased on average 359%, but the tip of the catheter, holding the floppy end of the guidewire, showed no significant increase in stiffness. A trend was seen showing larger percent differences in stiffness for smaller catheters (12F and 14F); indeed, the guidewire shaft stiffness approached the same stiffness as the shaft of a standard 20F catheter, but the stiffness of the catheter's tip remained unchanged. Clinically, the guidewire stiffening technique was used successfully in five of six patients; the failure was in a patient with a hitherto undiagnosed 8F urethral stricture.
  
  
  CONCLUSIONS
  In cases of difficult bladder catheter placement, the Super Stiff guidewire technique can be used to increase the stiffness of the catheter to navigate the torturous urethra with any size catheter before pursuing other more invasive and time-consuming techniques. If this maneuver fails, the same guidewire can be used in conjunction with the flexible endoscope to then place a Councill catheter.
authors: Department of Urology, University of California, Irvine, California 92868, USA. mliss@uci.edu
authors: Michael A
authors: MA
authors: Liss
authors: Sara
authors: S
authors: Leifer
authors: Ghassan
authors: G
authors: Sakakine
authors: Maria
authors: M
authors: Esparza
authors: Ralph V
authors: RV
authors: Clayman
mesh_terms: D002404:Catheterization / Q000191:economics / Q000379:methods*; D004724:Endoscopy; D006801:Humans; D008297:Male; D055595:Mechanical Phenomena