pectoral muscle atrophy

  I have been examined for neuro disease and I pass with flying colors.
  However, the interpretation of recent CT scan of my chest said "the pectoral
  muscles appear atrophic bilaterally".  
  Can these muscles appear atrophic for any reason other than atrophy?  If they
  are atrophied, what would cause this?  The nerves for this area come from
  up in the neck, don't they?  If so, wouldn't I have problems with my arms
  and hands?  They sometimes feel weak, but this is just a sensation I have, the
  neuro tests of arms and hands have been fine.
  I do know that when I breathe, my chest simply doesn't rise and fall like it
  used to.  I use my abdomen to breathe, but contracting the muscles there to
  fill up my lungs.  
  How are the muscles definitely tested for possible atrophy?
  Thanks for any thoughts/suggestions you might have...
  Ellen
===========================================================================
Dear Ellen:
Yours is an interesting question. Your problem is unlikely to be from an injury to or compression of the nerves in the neck (cervical spinal roots or brachial plexus). The fact that the atrophy is symmetric, and that you are quite or almost asymptomatic makes me think of slowly progressive heredofamilial myopathies, or of mild or gradually progressive heredofamilial or degenerative disorders of nerves or anterior horn cells.
The foremost possibility is of facioscapulhumeral dystrophy (FSHD).
Do you  sleep with your eyes slighly open, and do you have difficulty whistling/sucking with a straw? Do you have any relative with any muscular problem?
You need to be seen by a neurologist expert in neuromuscular disorders or myology. I can strongly recommend Dr. Mitsumoto, Dr. Levin, or Dr. Shields at the Cleveland Clinic, if you live in this area.
Good Luck!