You may get the following investigations to ascertain the cause;
A) Pulmonary function tests;
1) In spirometry you exhale in a mouthpiece which is connected to a computer. How fast and how much you exhale tells about the various lung functions and capacities.
2) Lung volume measurement is done by body plethysmography. One sits in a clear airtight small chamber and technologist asks you to breathe in and out of a mouthpiece. Changes in pressure inside the box help determine the lung volume.
3) The diffusion capacity is measured by breathing a harmless gas, for only one breath. The concentration of the gas in the air one breathes out is measured. The difference in the amount of gas inhaled and exhaled measures how effectively gas travels from the lungs into the blood.
B) High resolution CT scan of the chest.
C) MRI of neck; pinched nerves in neck can cause your symptoms.
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