I. What are urinary stones? We call stones that occur in the urinary system urinary stones. It includes stones in the kidney, ureter, bladder and urethra. Second, what are the risk factors for stone formation? There are many factors that affect stone formation. Age, gender, race, heredity, environmental factors, diet and occupation have a great impact on stone formation. Metabolic abnormalities in the body, obstruction of the urinary tract, infection, foreign body and drug use are common causes of stone formation. Attention to these problems can reduce stone formation and recurrence. What are the risks of urinary stones to the urinary system? The main risks of urinary stones to the urinary system are obstruction, infection and injury. Unilateral obstruction of the urinary system can cause hydronephrosis, which leads to enlargement of the renal pelvis and calyces in the long term, and finally the renal cortex atrophies into a water sac and loses its function. Bilateral obstruction can cause uremia. The combination of stone and infection can lead to stone pyelonephritis, pus accumulation, perinephritis, perinephric abscess, and eventually complete destruction of the kidney parenchyma. Stones, obstruction and infection are mutually beneficial, forming a vicious circle, i.e. stones cause obstruction, obstruction causes infection, and infection causes stones. In addition, stones can also directly cause damage to the kidney and bladder, and may cause squamous epithelial carcinoma through long-term stimulation of the mucosa, such as renal pelvis cancer and bladder cancer. 4.What are the main clinical symptoms of urinary stones? The common symptom of kidney and ureteral stones is back pain on the affected side. When renal colic attacks, the patient is restless and has paroxysmal severe pain, and because the kidney and gastrointestinal tract are innervated by the same abdominal cavity, renal colic is often accompanied by nausea, vomiting and abdominal distension. In colic caused by kidney stones, the pain may radiate in the direction of the ureter; in colic caused by ureteral stones, the pain may radiate in the direction of the groin, testicles or labia majora. Stones in the lower ureter may be accompanied by frequent and urgent urination. Blockage of the urinary tract by bilateral kidney, ureteral or isolated kidney stones may result in oliguria or anuria, and long-term severe obstruction may cause uremia. Symptoms of bladder and urethral stones are urinary frequency, urinary urgency, urinary pain, and difficulty in urination. Patients with urinary stones often have hematuria. V. What are the examination methods of urinary stones? The examination methods of urinary stones include laboratory tests and imaging tests. Among them, laboratory tests include blood analysis, urinalysis and stone analysis; imaging tests include ultrasound, plain urography (KUB), intravenous urography (IVU), CT scan, retrograde or percutaneous nephrostomy, magnetic resonance water imaging (MRU) and reflex nuclear scan. Ultrasound, plain urography (KUB) and intravenous urography (IVU) are the most commonly used imaging tests. ultrasound is easy, economical, non-invasive and can detect both positive and negative X-rays above 2 mm, and is the routine method for urinary stones, especially in cases of renal colic as the method of choice (Figure 1 shows ultrasound pictures of kidney, ureteral and bladder stones); plain urography ( KUB can detect about 90% of X-ray positive stones, and can roughly determine the location, morphology, size and number of stones, as well as give a preliminary indication of the chemical nature of the stones, it is also a routine method of stone examination (Figure 2 shows KUB pictures of kidney, ureter and bladder stones); intravenous urography (IVU) should be performed on the basis of urograms, which can not only understand the anatomy of the urinary tract, but also determine the location of stones in the urinary tract. It can not only determine the location of stones in the urinary tract and find out the X-ray negative stones that cannot be shown on the urogram, but also understand the function of the divided kidneys and determine the degree of hydronephrosis. Why some stones can be detected by ultrasound, but not by plain radiographs? This is because stones of different compositions appear differently on the plain urine film. According to the composition of the stones, they are in the following order: calcium oxalate, calcium phosphate and ammonium magnesium phosphate, cystine, and urate-containing stones. Simple uric acid stones and xanthine stones can pass through the X-ray, so these stones can be detected on ultrasound, but they do not show up on plain urine films. 7. Can intravenous urography be performed during an attack of colic for urinary stones? In general, intravenous urography is not recommended for urinary stones during an attack of colic. On the one hand, because of the poor visualization of intravenous urography during acute renal colic, it can only indicate acute renal impairment and cannot clarify the pathological pattern of the urinary tract; on the other hand, the contrast agent required for intravenous urography can further aggravate the renal impairment. What are the non-conservative treatment methods for urinary stones? The main treatment methods for kidney stones are: extracorporeal shock wave lithotripsy (ESWL), percutaneous nephrolithotomy (PNL), ureteroscopic stone extraction or lithotripsy, laparoscopic nephrolithotomy and open surgery. The main treatments for ureteral stones are: extracorporeal shock wave lithotripsy (ESWL), ureteroscopic lithotripsy or lithotripsy, percutaneous nephrolithotomy (PNL), laparoscopic ureterotomy and open surgery. The main treatment options for bladder stones are: extracorporeal shock wave lithotripsy (ESWL), intracavitary treatment and open surgery. Intracavitary treatment includes transurethral laser lithotripsy, transurethral pneumatic ballistic lithotripsy, transurethral mechanical lithotripsy, transurethral bladder ultrasound lithotripsy and transurethral electrohydraulic lithotripsy. The main treatment for urethral stones is similar to the intracavitary treatment for bladder stones, and the most commonly used treatments are holmium laser or pneumatic ballistic lithotripsy.