title: Lean and fat mass loss in obese patients before and after Roux-en-Y gastric bypass: a new application for ultrasound technique.
abstract: OBJECTIVE
  This study aims to evaluate the thickness of the femoral quadriceps and biceps brachii and brachialis muscles bilaterally and the adjacent subcutaneous fat in patients undergoing gastric bypass Roux-en-Y before and after surgery, using ultrasound as the diagnostic method of choice.
  
  
  METHODS
  We studied 12 patients undergoing this surgical method preoperatively and during the first, third, and sixth postoperative months. During these periods, patients were evaluated by ultrasound to determine the thickness of subcutaneous adipose tissue and muscle of the upper and lower limbs.
  
  
  RESULTS
  Postoperatively, these patients showed a reduction in the thickness of the upper and lower extremities muscle and adipose tissue as compared to their preoperative values. There was a significant difference in the loss of muscle thickness in all postoperative months and in the thickness of fatty tissue in the sixth month after surgery, compared to the preoperative muscle and fatty tissue thickness.
  
  
  CONCLUSIONS
  Ultrasound can be considered as the diagnostic method of choice when assessment of the fat and lean body mass is required in morbidly obese patients before and after bariatric surgery.
authors: Department of Medicine, Division of Endocrinology, UNIFESP, São Paulo, Brazil. andreap_pereira@hotmail.com
authors: A Z
authors: AZ
authors: Pereira
authors: J S
authors: JS
authors: Marchini
authors: G
authors: G
authors: Carneiro
authors: C H
authors: CH
authors: Arasaki
authors: M T
authors: MT
authors: Zanella
mesh_terms: D000328:Adult; D001823:Body Composition; D005260:Female; D005500:Follow-Up Studies; D015390:Gastric Bypass / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D011184:Postoperative Period; D057234:Preoperative Period; D052097:Quadriceps Muscle / Q000000981:diagnostic imaging* / Q000473:pathology; D050151:Subcutaneous Fat / Q000000981:diagnostic imaging* / Q000473:pathology; D014463:Ultrasonography; D055815:Young Adult