Ans. a (Ileocolic) (Ref. Bailey and Love 26th/pg. 114).ACUTE INTUSSUSCEPTION# Telescoping/invagination of one portion of the gut within an immediately adjacent segment; invariably it is the proximal into distal bowel. An intussusception is composed of three parts: the entering or inner tube; the returning or middle tube; and the sheath or outer tube (intussuscipiens).# most common in children, where it occurs in an idiopathic form with a peak incidence at 3-9 months.# Seventy to 95% of cases are classed as idiopathic. It is believed that hyperplasia of Peyer's patches in the terminal ileum may be the initiating event. This is due to weaning/viral infection.# Ileocolic type is otherwise most common and the colocolic variety is common in adults.# C/F: Intermittent sudden spasmodic abdominal pain, the 'red currant' jelly stool, palpable lump, feeling of emptiness in the right iliac fossa (the sign of Dance) and Empty RIF sign.# Ultrasonography is preferred over Barium enema today.# Ultrasound shows the mass with pseudokidney apperance or a target lesion or a bowel mass-like'doughnut sign.# A barium enema may diagnose by demonstrating signs like the claw sign and the coiled spring appearance.# Hydrostatic reduction is contraindicated in the presence of obstruction, peritonism or a prolonged history (greater than 48 hours) and is unlikely to succeed where a lead point is likely. It is successful in 50% of cases with a recurrence rate 5%.# Surgery is required where hydrostatic reduction has failed or is contraindicated. Reduction is achieved by squeezing the most distal part of the mass in a cephalad direction. Do not pull. In difficult cases the little finger may he gently inserted into the neck of the intussusception to try and separate adhesions (Cope's method).# In the presence of an irreducible or gangrenous intussusception the mass should be excised in situ and an anastomosis or temporary end stoma created.