Laser lithotripsy is a minimally invasive medical procedure used to treat hard deposits, known as calculi, that form in the urinary tract. This technology uses concentrated laser energy delivered through a thin, flexible scope to break down stones located in the kidneys, ureters, or bladder. Urologists access and treat stones without requiring a surgical incision. By fragmenting the stones into manageable pieces, the procedure enables them to be removed or passed naturally. This method manages stones that are too large, too hard, or improperly positioned to pass.
How Laser Energy Breaks Down Stones
Focused laser light is delivered directly onto the calculus through a fine fiber optic cable to destroy the stone material. The specific mechanism depends on the type of laser used, with the two most common being the Holmium:YAG (Ho:YAG) and the Thulium Fiber Laser (TFL). The Ho:YAG laser, long considered the standard, operates primarily through a photothermal effect. This means the laser energy is intensely absorbed by the water within the stone’s structure, causing rapid heating and vaporization.
This intense heat leads to the thermochemical decomposition of the stone material and the creation of a small vapor bubble at the fiber tip. The energy transfer is focused on dissolving the stone rather than relying on mechanical force. In contrast, the newer TFL uses a synergic approach, combining thermal destruction with the explosive boiling of water within the stone’s pores. This high-efficiency method converts the stone material into a very fine powder, referred to as “dusting.”
The ability to control the laser parameters allows the surgeon to choose between two main outcomes: fragmentation or dusting. Fragmentation uses higher pulse energy to break the stone into larger pieces that must be physically removed. Dusting uses lower energy pulses at a high frequency, which vaporizes the stone into fine particles that can be flushed out or passed naturally. The TFL is especially effective at dusting, ablating the stone more quickly and reducing the need for physical extraction of fragments.
Step-by-Step Guide to the Procedure
The laser lithotripsy procedure typically begins with the patient under general anesthesia for comfort and immobility. The patient is carefully positioned on the operating table, and the surgical team prepares the area for sterile access to the urinary tract. The procedure is performed by inserting a thin, specialized instrument called a ureteroscope into the body through the urethra, requiring no external incisions.
The urologist guides the ureteroscope through the bladder and up the ureter, the tube connecting the kidney and bladder. For stones lodged in the middle or lower ureter, a semi-rigid scope may be used. A flexible ureteroscope is necessary to navigate tight bends and reach stones located within the kidney. The scope contains an optical system that transmits a video image to a monitor, allowing the surgeon to visualize the stone clearly.
Once the stone is located, a fine laser fiber is passed through a working channel in the scope until its tip rests in direct contact with the stone. The surgeon activates the laser, applying energy precisely to break the calculus into smaller pieces.
Following fragmentation, the resulting pieces are managed in one of two ways. Smaller pieces or fine dust are flushed out with irrigation fluid and passed from the urinary tract. Larger fragments are captured using a tiny basket device inserted through the scope and withdrawn. The entire procedure generally takes between 30 and 90 minutes, depending on the stone’s size, composition, and location.
What to Expect During Recovery
Immediately following the procedure, patients are monitored in a recovery area; most patients go home the same day, as it is an outpatient procedure. It is common to experience discomfort, including pain in the abdomen or flank, and increased urinary frequency for a few days. Seeing blood in the urine is normal and temporary, resulting from the scope’s passage and the laser’s action within the urinary tract.
In many cases, a temporary ureteral stent is placed at the end of the operation while the patient is still under anesthesia. This thin, hollow tube runs from the kidney into the bladder, designed to keep the ureter open and allow post-procedure swelling to subside. The stent ensures that urine and any remaining stone fragments can pass freely, protecting the kidney from obstruction and potential infection.
The stent itself can cause noticeable symptoms, including bladder irritation, a strong urge to urinate, and flank pain that may worsen during urination as urine flows back up the stent. These symptoms are expected and typically resolve once the stent is removed. Removal generally occurs between 3 and 14 days after the procedure, though the stent may remain in place for several weeks depending on the surgery’s complexity. Maintaining a high fluid intake helps to flush the urinary system and expedite the passage of any residual stone dust.