Diagnositic value and image classification of 99Tcm-DX lymphoscintigraphy in intestinal lymphangiectasia

Abstract

Objective To investigate the image classification and diagnostic value of 99Tcm-DX lymphoscintigraphy in intestinal lymphangiectasia (IL).Methods A total of 68 patients (the study group) with clinical suspicion of IL from June 2007 to September 2012 were retrospectively analyzed.Using a stratified sampling method,60 patients with lower limb lymphedema or chylous ascites (the control group) were selected by age-and gender-matched with the study group.All patients underwent 99Tcm-DX lymphoscintigraphy.The lymphoscintigraphic findings were classified according to the imaging characteristics in abdomen.The intestinal tract could be shown on the images of 99Tcm-DX lymphoscintigraphy was the diagnostic standard of IL.Results According to the histopathology results,60 cases of the study group were finally diagnosed as IL and 8 cases were excluded.Five patterns of 99Tcm-DX images in abdomen were classified as following:pattern Ⅰ,consecutive visualization of intestine; pattern Ⅱ,delayed visualization of intestine; pattern Ⅲ,accumulation in ascites ; pattern Ⅳ,hybrid; pattern Ⅴ,negative results.The cases of Ⅰ,Ⅱ,Ⅲ,ⅣandⅤin the study group and control group were 19 vs 0,17 vs 4,11 vs 13,6 vs 0 and 7 vs 43,respectively.The sensitivity,specificity,accuracy,positive predictive value and negative predictive value of 99Tc m-DX lymphoscintigraphy in diagnosing IL were 70.0％ (42/60),94.1％ (64/68),82.8 ％ (106/128),91.3％(42/46) and 78.0％(64/82),respectively.Conclusions 99Tcm-DX lymphoscintigraphy may be an important diagnostic method for IL,and the visualization of intestine is an important evidence for the diagnosis of IL. Key words: Lymphangiectasis, intestinal; Radionuclide imaging; Dextrans