Normal mediastinal lymph node size and shape; CT and cadaver study

With the view point of size, shape and arrangement pattern, authors present normal mediastinal lymph node fromthe analysis of 61 cases of CT scan and multidirectional section of 2 cadavers. The results were as follows: 1.Transverse diameter of the lymph nodes, demonstrated in cadaver section, was 3 to 6mm in upper paratracheal areaand 5 to 14mm in juxta-carinal and AP-window area. Arrangement of the lymph nodes showed tendency of longitudinaldirection in lower paratracheal, and juxtacarinal area, while that of AP window showed tendency of AP direction aslong axis. 2. Mean and the largest size of the lymph nodes demonstrated in CT scan were 3.7mm, 8mm in upperparatracheal area, and 6mm, 12mm in lower paratracheal area, and 7.1mm, 14mm in juxtacarinal area, and 6.3mm and11mm in aorticopulmonary window area. 3. Size fo the lymph nodes in CT scan showed linear increasing tendencyaccording to increasing age(y=0.32, p<0.005). 4. Shape of the lymph nodes in CT scan were mostly round in upperparatracheal area while that of aorticopulmonary window showed higher incidence of oval and elongated shape. 5.Recommended size criterior of abnormal lymph node is 10mm in upper paratracheal are and 15mm in the other area.