Urinary stones are solid masses made of crystals which usually develop in the kidneys, though they can develop anywhere along the urinary tract – kidney, ureter, bladder and urethra. Depending on the location of the stone, the stone is referred to as a kidney stone, ureteral stone or bladder stone. Also, varying by the location of the stone, the process of stone formation is called urolithiasis, renal lithiasis or nephrolithiasis. These stones are formed due to the excessive accumulation of certain minerals in the body and the lack of fluids to dissolve the accumulated minerals which can include calcium, oxalate and uric acid. Moreover, other factors such as poor diet, severe diarrhoea, excessive weight, family history or certain medications can also lead to the formation of stones along the urinary tract.
Urinary stones especially, kidney stones are one of the most painful medical conditions and are very common in middle-aged and older men and women. Stones vary in size from too small (not visible through the naked eye) to big approximately 2.5 centimetres in diameter or more. While tiny stones often do not cause any symptoms and can pass on their own, large stones can cause intense pain in the area between the ribs and hips in the back. Some stones can be passed with the help of medications, while others would need to be treated medically depending on the size, location and severity of symptoms.
Extracorporeal Shock Wave Lithotripsy (ESWL): This is a form of lithotripsy procedure that uses high-frequency shock waves to break down the stones in the urinary tract. In this method of treatment, an instrument known as a lithotripter is used to direct high-energy sound waves to focus ultrasonic energy directly at the stones, causing them to break into smaller pieces. The basic advantage of this type of treatment of urinary stone is that it does not cause any damage or harm to the surrounding organs and tissues since the energy is aimed directly at the stone, through shock waves which travel into the body from the skin and tissue. Post the treatment, the smaller pieces of stones are eventually passed through urine over several days or weeks. ESWL procedure is approximately an hour-long procedure and has a shorter hospital stay and faster recovery time. This method of urinary stone management is non-invasive and is preferred over invasive procedures; however, certain conditions must be met to perform the medical procedure.
Percutaneous Nephrolithotomy (PCNL): This method of urinary stone management is used when the stone is large enough and cannot pass on its own. The method involves making a small incision on the back to remove the stone; the surgery is performed majorly in case of kidney stones that are too large – more than 2 cms in diameter or are too dense to be treated with any other method such as an ESWL. PCNL is a minimally invasive method in which a tube is inserted into the kidney (via guidance from X-rays) through the incision made on the back. Once the tube is in place, a telescope is passed through the tube to get a clear picture of the stone/stones and then break the stone and remove it from the body. In case, the stone is too large, a lithotripter can be used to break the stone first before removing it through a PCNL procedure. A PCNL procedure is safe and has minimum post-operative complications, shorter recovery time and shorter stay in the hospital as compared to an open stone surgery. This form of treatment has more success rates as compared to an ESWL. Moreover, it is also very effective when large kidney stones cause a lot of complications such as blocking more than one collecting branch of the kidney; or there is the presence of large stones in the ureter and other therapies have failed to provide results.
Miniaturized Percutaneous Nephrolithotomy (PCNL) (MINI-PERC): This is a minimally-invasive form of PCNL method that has lesser disadvantages as compared to a PCNL technique of stone removal. This method is an improvised version of stone removal in which a percutaneous nephrolithotomy is performed in one step by using a 16 G micro-puncture needle. In more advancement, mini-micro perc uses an 8 Fr sheath to insert ultrasonic energy to treat urinary tract stones, especially kidney stones. This method has more advantages as compared to a PCNL, such as the low risk of haemorrhage, low post-operative pain, faster recovery and shorter hospital stay.
Retrograde Intrarenal Surgery (RIRS): RIRS is an endoscopic surgery performed to remove renal stones by reaching the kidney from the ureter. RIRS procedure uses a viewing tube called a fibre optic endoscope and a laser fibre – Holmium – to treat renal stones. Once the large stone is removed, small fragments of the stones are taken off through stone baskets. In some cases, a stent may be pushed into the kidney to improve drainage. Post the procedure, the endoscope is crushed, blasted or evaporated by using a laser probe or can also be manually removed through forceps. The surgery is performed by a urologist who has specialized expertise in RIRS. During the procedure, the patient is given local, spinal or general anaesthesia and the endoscope is inserted into the body through the urethra and then onto the kidney; the surgery does not involve any incisions and hence, has a very fast recovery time. With RIRS a vast majority of renal stones can be cleared without open surgery. Also, with recent medical advancements, RIRS has become none of the most reliable, safe and efficient methods to treat urinary tract stones. This method aims to clear the stones with minimum morbidity, RIRS clears renal stones through flexible ureterorenoscopy and lithotripters including holmium laser, ensuring no trace of stones are left. Moreover, advancements in related equipment such as guide wires, urethral access sheaths and stone baskets have enhanced the effectiveness of the RIRS procedure. As of today, RIRS is a prime method of treatment for renal stones that are less than 2 cm and cannot be successfully treated via other methods.
These methods of urinary stone management are minimally invasive and very effective in removing stones along the urinary tract.