Marked decreased FEV1 and FEV1/ FVC ratio are seen in
In obstructive diseases like asthma,marked fall in FEV1 and FEV1/FVC ratio is present.In restrictive diseases like kyphoscoliosis and fibrosis,lung volumes like TLC,FRC,RV as well as FVC are lowered.Maximal expiratory flows like FEV1 are also reduced compared with normal values,but are relatively elevated when considered in relation to lung volumes.So FEV1/FVC ratio will be normal or slightly increased Ref:Harrison's medicine-18th edition,page no:2093.
Asthma
Kyphosis
Scoliosis
Fibrosis of lung
Respiratory system