title: Lymphangioleiomyomatosis: CT of diurnal variation of lymphangioleiomyomas.
abstract: OBJECTIVE
  To evaluate the imaging and clinical features of lymphangioleiomyomas and to describe the phenomenon of diurnal variation in the size of lymphangioleiomyomas in patients with lymphangioleiomyomatosis.
  
  
  METHODS
  One hundred twenty-eight patients with lymphangioleiomyomatosis underwent chest and abdominopelvic computed tomography (CT). Thirteen patients underwent CT in the morning and afternoon of the same day to assess diurnal variation in lymphangioleiomyoma size.
  
  
  RESULTS
  Twenty-seven of 128 patients (21%) had 54 lymphangioleiomyomas. The vast majority (96%) of these masses contained material of low attenuation at CT. Associated CT findings included enlarged abdominal lymph nodes, pleural effusions, ascites, and dilatation of the thoracic duct. The prevalence of lymphangioleiomyomas was 15% in patients who had mild pulmonary disease, 19% in patients who had moderate disease, and 26% in patients who had severe disease. Diurnal variation in size of masses was demonstrated in 12 of 13 patients. Seven of the 27 patients who had masses underwent biopsy; all seven were confirmed to have lymphangioleiomyomas. The most common symptoms associated with lymphangioleiomyomas were bloating, abdominal pain, and edema of the lower extremities. The majority of the patients reported worsening of symptoms as the day progressed.
  
  
  CONCLUSIONS
  Lymphangioleiomyomas are common in patients with lymphangioleiomyomatosis. Diurnal variation in size may explain worsening of symptoms during the day.
authors.affiliation: Department of Diagnostic Radiology, Warren Grant Magnuson Clinical Center, National Institutes of Health, Bldg 10, Rm 1C-660, 10 Center Dr MSC 1182, Bethesda, MD 20892-1182, USA. navila@nih.gov
authors.forename: N A
authors.initials: NA
authors.lastname: Avila
authors.forename: J
authors.initials: J
authors.lastname: Bechtle
authors.forename: A J
authors.initials: AJ
authors.lastname: Dwyer
authors.forename: V J
authors.initials: VJ
authors.lastname: Ferrans
authors.forename: J
authors.initials: J
authors.lastname: Moss
mesh_terms: D000008:Abdominal Neoplasms / Q000000981:diagnostic imaging*; D000328:Adult; D000368:Aged; D002940:Circadian Rhythm; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology; D018192:Lymphangioleiomyomatosis / Q000000981:diagnostic imaging*; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary / Q000000981:diagnostic imaging; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed