<prompt> Inferior rib notching is present in -Coarctation of aortaTAPVCFallots tetralogyVentricular septal defect  <response>: Ans. is ac i.e., Coarctation of aorta Fallots tetralogy o Causes of rib notching ae : -A Inferior surface1 Arteriali Coarctation of aorta Bilateral Rib notching is seen on the lower border of 3rd to 8th ribs. Rib notching is absent in the 1st 2nd ribs. Rib notching is usually present after the age of 7 years.ii Aortic thrombosis aortic obstruction or aortitis.iii Subclavian obstruction after Blalock operation for Fallots tetralogy Taussig Blalock operation.iv Pulmonary oligemia Pulmonary atresia, TOF, absent pulmonary artery.2 Venous : - SVC obstruction3 Arteriovenous : - Pulmonary arteriovenous malformation, chest wall arteriovenous malformation.4 Neurogenic : - Neurofibromatosis.B Superior surface1 Connective tissue diseases : - SLE, Scleroderma, RA, Sjogrens syndrome.2 Metabolic : - Hyperparathyroidism3 Miscellaneous : - Neurofibromatosis, Restrictive lung disease, Poliomyelitis, Marfans syndrome, progeria, Osteogenesis imperfecta. 