Dr. Dean Cerf, Ridgewood Veterinary Hospital NJ and Dr. Eric Lindquist, SonoPath.com
For More Information Contact Dr. Dean Cerf at Ridgewood Veterinary Hospital, Ridgewood, NJ, USA 001 201 447 6000 or lnk to www.ridgewoodvet.com.
Video 1 - Ultrasound-guided endoscopic biopsy of a cystourethral junction transitional cell carcinoma in a 13-year-old FS Pit Bull Terrier. This is performed before the Ultasound-Guided Endoscopic Laser Ablation (UGELAB) procedure is performed.
Video 2 - Low wattage UGELAB procedure demonstrating the formation of the Hyperechoic Tissue Necrosis Line (HTNL) during endoscopic-guided diode laser ablation. As the tumor tissue necrosis occurs the tumor becomes more dense and, therefore, more hyperechoic causing the formation of the HTNL. The sonographer can monitor the progression of the HTNL to maximize tumor kill and maintain bladder wall integrity to avoid perforation. The remaining HTNL tissue sloughs and is voided over the following days post UGELAB.
Video 3: HTNL formation within the tumor at 25 Watts shows rapid extention to the bladder wall as a "soft spot" is ablated. Without sonographic assessment of the HTNL the endoscopy-laser operator would not see the potential for rupture of the bladder wall. Based on this occurrence, the wattage was reduced to 16 Watts to allow for less aggressive laser penetration during the remainder of the UGELAB procedure.
Image 4: Endoscopic view of the UGELAB. As the endoscope enters the urethra and cystourethral junction where the tumor resides in this patent, we can see the full obstruction of the urinary tract by the tumor and imagine how the clinical signs of mid voiding dysuria occurs since urine passes when the bladder is full but is obstructed when the bladder collapses to moderate repletion. Laser ablation is then seen but the endoscope-laser operator can only visualize the superficial aspects of the tumor. "It is like imagining what a room has in it by looking at the door." Simultaneous sonography allows for visualization of the "contents of the room" such as blood vessels, ureters, and bladder wall. The sonographic aspects show HTNL formation and a tumor "tunnel" that was produced during the procedure. End procedure endoscopic view shows the minimal remaining tumor followed by a 1 month follow-up demonstrating full patency with minimal tumor presence and a minor laser clean-up procedure.The 3 still image series shows a) Tumor before UGELAB b) End procedure, and c) Follow-up images demonstrating full patency of the cystourethral junction.
Video 5: End of procedure. Foley catherter placement. Post UGELAB procedure in which a foley catheter is placed. Ultrasound guidance allows for correct seating of the catheter at the cystourethral junction to ensure adequate voiding and allow for passive healing of the urinary tract to occure in the few days post UGELAB.
