title: Lymph proteins may access peripheral blood without entering thoracic duct in patients with lymphatic dysfunction.
abstract: OBJECTIVE
  The objective was to investigate the hypothesis that lymphovenous communications, which allow lymph proteins to access peripheral blood without first entering the thoracic duct, open in patients with abnormal lymphatic function.
  
  
  METHODS
  Routine lymphoscintigraphy of 182 patients, including 27 without clinical evidence of lymphedema (controls), was performed immediately and 45 and 150 minutes after subcutaneous injection of technetium Tc 99m nanocolloid into both feet. Counts per pixel in a region of interest over the liver (L) were divided by total counts in bilateral ilioinguinal nodes (N) at 45 minutes (L/N45) and 150 minutes (L/N150). If all activity leaving ilioinguinal lymph nodes entered the thoracic duct, these L/N ratios would be similar from patient to patient.
  
  
  RESULTS
  Eight patients were excluded because of immediate liver activity suggesting inadvertent intravascular injection of tracer. In controls (group 1), L/N150 displayed a normal distribution with mean (± standard deviation) of 0.16 (0.09) × 10(-4) pixels(-1). Patients with L/N150 >0.34 × 10(-4) pixels(-1) (ie, 0.16 + 2 standard deviations) were assumed to have lymphovenous communications. Of 34 patients with clinical evidence of lymphedema but with normal findings on lymphoscintigraphy (group 2), 3 (9%) had lymphovenous communications; of 114 with abnormalities on lymphoscintigraphy (group 3), 43 (38%) had lymphovenous communications (P = .001). N45/150 was significantly higher than L45/150 in all four groups, indicating arrival of activity in nodes before the liver. Abnormal features of lymphoscintigraphy-lymph transport delay, popliteal node visualization, and diversion of lymph through the skin-showed no association with L/N ratios.
  
  
  CONCLUSIONS
  Lymphovenous communications exist in about one-third of patients with abnormalities detected on lymphoscintigraphy. The timings of tracer arrival in the liver and lymph nodes is consistent with lymphovenous communication within lymph nodes themselves.
authors.affiliation: Molecular Imaging Department, Harley Street Clinic, London, United Kingdom.
authors.forename: Magda M
authors.initials: MM
authors.lastname: Soares
authors.affiliation: Molecular Imaging Department, Harley Street Clinic, London, United Kingdom; Division of Clinical and Laboratory Investigation, Brighton and Sussex Medical School, Brighton, United Kingdom.
authors.forename: Georgia
authors.initials: G
authors.lastname: Keramida
authors.affiliation: Molecular Imaging Department, Harley Street Clinic, London, United Kingdom.
authors.forename: Daphne M
authors.initials: DM
authors.lastname: Glass
authors.affiliation: Cardiovascular and Cell Sciences Research Institute, St George's, University of London, London, United Kingdom.
authors.forename: Peter S
authors.initials: PS
authors.lastname: Mortimer
authors.affiliation: Molecular Imaging Department, Harley Street Clinic, London, United Kingdom; Division of Clinical and Laboratory Investigation, Brighton and Sussex Medical School, Brighton, United Kingdom. Electronic address: a.m.peters@bsms.ac.uk.
authors.forename: Adrien Michael
authors.initials: AM
authors.lastname: Peters
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001798:Blood Proteins / Q000378:metabolism*; D002648:Child; D005260:Female; D006801:Humans; D008196:Lymph / Q000378:metabolism*; D008198:Lymph Nodes; D008208:Lymphatic System; D042601:Lymphatic Vessels; D008209:Lymphedema / Q000209:etiology; D061305:Lymphoscintigraphy; D008297:Male; D008875:Middle Aged; D013897:Thoracic Duct; D055815:Young Adult
chemical_list: D001798:Blood Proteins