<s>[INST] context: (Increased peristalsis of the ureter to overcome obstruction) (31-Smith Urology 17th,1274-Baily & Love 25th)The severity and colicky nature of ureteric colic pain are caused by the hyper peristalsis and spasm of smooth muscles of the ureter as it attempts to rid itself of a foreign body or to overcome obstruction (smith urology 17th)Pain from acute obstruction of ureter(Stone or Blood clot)|| |Back Pain Severe colicky painThis results from capsular distensionThis results from renal, pelvic and ureteral muscle spasm. The severity and colicky pain are caused by the hyperperistalsis and spasm of this smooth muscle organ (Ureter) as it attempts to rid itself of a foreign body or to overcome obstruction* Pain classically radiates from costovertebral angle down towards the lower anterior abdominal quadrant* In Men - It may also be felt in the bladder, scrotum or testicle* In women - it may also be felt in the vulvaLocation of Ureteric Pain Stone in upper ureter - Pain radiates to testicles (T11T12) Nerve supply of testicles is similar to that of kidney & upper ureter Stone in the midportion of ureter(i) Right side - Pain referred to Me Burney's point and stimulates appendicitis (T12L1)(ii) Left side - Pain referred to left lower quadrant and stimulates diverticulitis or other disease of the descending or sigmoid colon (T12-L1) Stone in the lower portion(i) Proximal to orifice - Pain is referred to inner side of thigh or groin (L1 L2)(ii) At the level of orifice or orifice involved due to edema symptoms of vesical irritability such as frequency and urgency may occur* Ureteric peristalsis is due to intact supply of - Intrinsic smooth muscle pacemaker activity of renal calyces**** The narrowest part of ureter is at the - uretero-vesical junction*** Highest incidence of ureteric injury in- Wertheim's hysterectomyUreteric Constriction - Sitesi. Ureteropelvic junctionii. Crossing of the iliac arteryiii. Juxta position of the vas deferens or broad ligamentiv. Uretero vesical junctionv. Ureteric orifice* Phosphate stones (Staghorn calculi)Excess alkali consumption, Alkali urine*Infection with urease splitting organism eg Proteus, kleibsella, Pseudomonas* Cystine stoneForm in acidic urine*, Extremely hard stone,Relatively resistant to fragmentation with ESWL**The most sensitive imaging modality for diagnosis ureteric stone in a patient with acute colic is - Non contrastCT scan of the abdomenArterial supply of ureter are as follows(a) upper end(b) Middle portion(c) PelvisRenal arteryTesticular or ovarian arterySuperior vesical artery [/INST] question: Ureteric colic due to stone is caused by | options: A: Stretching of renal capsule due to back pressure B: Increased peristalsis of ureter to overcome the obstruction C: Irritation of intramural ureter D: Extravasation of urine | answer: B </s>