耳鼻咽喉科領域におけるＣＴ上の辺縁増強効果についての検討

Abstract

The authors evaluated various head and neck lesions seen from April 1988 through March 1990 both by plain and enhanced CT, examined the incidence of rim effect (or rim enhancement), classified these effects, and discussed underlying mechanisms. Materials consisted of 177 cases including primary tumors (28 benign and 49 malignant cases) and lymphadenopathy associated with malignancy (9 cases, metastatic nodes and malignant lymphomas), inflammatory lesions (20 cases), cystic lesions (12 cases), other lesions (7 cases, jugular thrombosis, carotid atheroma and aural lesions), and 22 cases without abnormal findings. Among the 177 cases, rim effects were observed in 22 cases (12%). These effects were analyzed and classified. The incidences of rim effect according lesion type are as follows; cervical lymphadenopathy associated with malignancy 5/9 (56%), primary tumors 8/77 (10%), inflammatory lesions none, cystic lesions 7/12 (58%), and others 3/7 (43%). The highest incidence was seen with cystic lesions including mucoceles of the paranasal sinuses and cervical cysts. Rim effects were classified as follows; Type 1: cystic pattern, Type 2: parenchymatous pattern, Type 3: vascular pattern and Type 4: others. Type 1 was seen in 15 cases (68%), Type 2 in 3 cases (14%), Type 3 in 3 cases (14%), and Type 4 in 1 case (5%). Type 1 included 6 cystic lesions, 3 malignant lymphadenopathies, 3 benign tumors and others. Type 2 included 2 malignant lymphadenopathies and 1 benign tumor, and Type 3, 2 jugular thromboses and 1 carotid atheroma. There was only one Type 4, a cystic lesion. Of interest is the mode of incidences among cervical lymphadenopathies associated with malignancy.(ABSTRACT TRUNCATED AT 250 WORDS)