Feasibility of cannula-free single-port percutaneous cystolithotomy using a 5-mm operative hysteroscope in dogs with varying procedural constraints: a retrospective case series

Abstract Conventional percutaneous cystolithotomy (PCCL) in dogs typically relies on a transvesical access cannula as the working channel for stone retrieval. This retrospective case series evaluated the feasibility and clinical outcomes of a novel cannula-free single-port PCCL technique in dogs with varying procedural constraints. Procedural constraints were retrospectively characterized using an exploratory composite framework incorporating body-related and disease/anatomy-related factors. The technique repurposes a 5-mm operative hysteroscope as a laparoscopic access device, enabling bladder visualization and traction through an initial single 5-mm access site before conversion to a cannula-free working window for stone retrieval. Ten dogs underwent the procedure, and procedural completion, stone removal, operative time, postoperative recovery, and perioperative clinical findings were evaluated. The intended procedure was completed in all 10 dogs, including three cases classified as high-constraint, with complete stone removal achieved in every case. Operative times and times to sternal recumbency and standing varied among dogs, while postoperative pain scores decreased from 6 to 24 h after surgery. These findings provide preliminary evidence supporting the clinical feasibility of cannula-free single-port PCCL in dogs presenting a range of procedural constraints, including cases with multiple concurrent constraints. Larger studies are needed to further characterize its clinical outcomes.