<prompt> Non contrast ct is investigation of choice forMediastinal massLung massNodular thickening of pleuraInterstitial lung disease  <response>: 16 D Interstitial lung disease 707- Davidson 22ndHigh resolution CT is superior to the plain chest x ray for early defection and confirmation of suspected ILD 2163-H 18TH.Clinical assessment including chest x-ray, pulmonary function test, haematology, biochemical andimmunological investigations High -resolution CT Appearances consistent with usual interstitial pneumonia Inconsistent clinical or CT appearances Appearances consistent with another diffuse parenchymal lung disease e,g, sarcoid Diagnose idiopathic pulmonary fibrosis Further investigations, e,g, bronchoalveolar lavage, transbronchial biopsy, surgical biopsy Diagnose and treat accordinglyAlgorithm for the investigation of patients with interstitial lung disease following initial clinical and chest X-ray examination. 