<prompt> Sequestration lung is best diagnosed by-CT. scanM.R.I.Barium swallowAngiography  <response>: A pulmonary sequestration bronchopulmonary sequestrationis a medical condition wherein a piece of tissue that ultimately develops into lung tissue is not attached to the pulmonary aerial blood supply.An angiogramaeriogram has been considered vital in documenting the systemic blood supply,allowing definitive diagnosis as well as preoperative planning. 