Diagnostic value and image classification of ⁹⁹Tc^m-DX lymphoscintigraphy in intestinal lymphangiectasia

Objective: To investigate the image classification and diagnostic value of ⁹⁹Tc^m-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 ⁹⁹Tc^m-DX lymphoscintigraphy. The lymphoscintigraphic findings were classified according to the imaging characteristics in abdomen. The intestinal tract could be shown on the images of ⁹⁹Tc^m-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 ⁹⁹Tc^m-DX images in abdomen were classified as following: pattern I, consecutive visualization of intestine; pattern II, delayed visualization of intestine; pat-tern III, accumulation in ascites; pattern IV, hybrid; pattern V, negative results. The cases of I, II, III, IV and V in 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: ⁹⁹Tc^m-DX lymphoscintigraphy may be an important diagnostic method for IL, and the visualization of intestine is an important evidence for the diagnosis of IL. (authors)