Introduction
Kidney stone formation is a frequent medical condition and is more common in men. The stones can form in any part of the urinary tract. If the ureter gets blocked, urine gets built up in the kidneys, leading to kidney damage. There is also an increased risk of developing kidney infection, which may progress to kidney failure. Ureteroscopy has been used since 1980 for renal stone clearance and diagnosis of renal diseases.
What Are Kidney Stones?
Kidney stones are known as nephrolithiasis. Kidney stones form 10 to 20 percent of all renal stones and require surgical intervention. The type of surgical intervention depends on the size and location of the renal stone. Surgically treating the renal stones helps relieve the patient’s discomfort, clears infection, and improves kidney function impairment caused by renal or ureter stones.
What Are the Prerequisites for Surgical Intervention of Renal Stones?
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The surgical procedure is successful when stones are completely removed, or there is a higher stone-free rate. The need for surgical treatment must be lower.
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The surgical technique must have fewer complications.
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Following the procedure, the patient’s quality of life must be improved.
What Are the Indications for Renal Stone Clearance?
Surgical treatment for asymptomatic stones less than 5 mm (millimeter) is not required. A surgical procedure is indicated when the patient develops pain, urinary tract obstruction, or infection. However, surgical renal stone removal is recommended for pilots, women wanting to conceive, or individuals who like to avoid emergency renal complications.
Indication for an Emergency Procedure: When a patient has severe pain and urinary tract infection, emergency decompression of the collecting system is carried out along with antimicrobial therapy. A stent is placed to drain the collecting duct.
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Individuals with obstructing renal stones along with urinary tract infections.
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Individuals with bilateral renal stone obstruction and acute renal injury.
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Patients with unilateral renal obstruction and acute kidney injury in functional kidney.
Indications for Elective Surgery:
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Urethral stones larger than 10 mm.
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Uncomplicated urethral stones less than 10 mm that have not passed even after four to six weeks of observation.
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In patients with symptomatic kidney stones.
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Recurrent urinary tract infections due to renal stones.
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Kidney obstruction caused by renal stones.
What Is Ureteroscopy?
Ureteroscopy is an emergency or elective renal surgical procedure. Ureteroscopy uses a ureteroscope device that is flexible or rigid and can directly treat kidney stones. A video image and small channels are available on the device. With the help of video, the cystoscopy is inserted into the bladder and ureter until the stone is found. Followed by guidewire and ureteroscope insertion. The stones are broken with the help of laser fiber and removed by small baskets inserted through small channels. In a few cases, the smaller stones are left behind to pass from the body naturally. The benefit of this procedure is the body’s openings are used for passing the device, and no incisions are required.
The procedure effectively removes small stones but may cause mild discomfort when stents are needed. However, the treatment of larger stones is complex due to the smaller instrument size. The ureteroscope is the first line of treatment for proximal, distal, and mid-ureteral stones that are larger or smaller than 10 mm. A second or third ureteroscopy is needed for the removal of complex stones.
In Which Patient Groups Are Ureteroscopy Preferred?
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Obese Patients: Ureteroscopy is a preferred surgical procedure in obese patients as it depends less on body habits.
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Pregnant Patients: Ureteroscopy is the preferred technique in pregnant patients needing surgical stone removal.
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Bleeding Diathesis Patients: For individuals with bleeding disorders or requiring continuous antiplatelet and anticoagulant therapy, ureteroscopy is considered the first line of treatment.
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Abnormal Ureter or Kidney Anatomy: Patients with abnormal kidneys or ureters are treated with an endoscopic procedure using a ureteroscope. A ureteroscopy can also help with the correction of anomalies.
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Stone Composition: The composition of the renal stone is inspected by pre-procedure computed tomography. Kidney stones composed of calcium oxalate monohydrate, brushite, cystine, and high-density homogeneous substances are harder to treat and require ureteroscopy intervention.
What Are the Measures to Follow After Ureteroscopy?
For the initial days after the procedure, the doctor may prescribe antibiotics. Most patients experience mild to moderate pain that is relieved with pain medications. After two hours of ureteroscopy, the patient must drink two glasses of water.
What Are the Complications Seen Following Ureteroscopic Renal Stone Clearance?
The following complications develop after ureteroscopy:
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Silent obstruction is a significant complication that can cause progressive renal failure. Therefore, imaging after three months of ureteroscopic stone removal helps avoid this complication.
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Urinary tract infection can develop after ureteroscopy. After stone removal, a follow-up urine analysis is needed. If there is an infection, appropriate antibiotics must be taken.
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Other Complications: Sepsis, urethral stricture, urethral avulsion, and urethral perforation.
How Successful Is Ureteroscopy for Renal Stone Clearance?
Ureteroscopy is a minimally invasive procedure. Introducing a flexible ureteroscope has enabled the clearance of renal stones from the upper ureters and kidneys. The success of the ureteroscope is examined by the stone-free rate following ureteroscopy. The stone-free rate is 77 to 81 percent for kidneys and 91 to 100 percent for ureter stones. The main goal of treatment with a ureteroscope is to break the larger stone and remove stones larger than 1 mm. It allows the natural clearance of smaller kidney stones. However, one of the limitations of a ureteroscope is that residual stones that must undergo natural clearance from the body could regrow. It could cause recurrent renal stones needing retreatment. Therefore, all renal stones in the initial ureteroscopy must be removed to avoid the need for subsequent intervention.
The stone-free rate of the ureteroscope can be improved by using medical expulsion therapy like Tamsulosin or anti-retropulsion devices. Placing the patient in a flank position during the ureteroscope can move the stones in a favorable position and help in effective stone removal. However, further research is required to determine their efficacy.
Conclusion
Renal stone is a common health issue, and asymptomatic cases do not need treatment. If the patient is symptomatic, elective or emergency procedure is advised. Ureteroscopy is a preferred minimal-invasive surgery for most renal stones. This procedure removes larger stones, and stones less than 1 mm are left to be cleared naturally. However, there is an increased risk of stone regrowth requiring additional ureteroscopy. Studies are ongoing to avoid retreatment procedures after ureteroscopy.
