INTRODUCTION:The ingredient of substances which are implanted for breast augmentation sometimes remain unknown due to lack of information from patients, which may causes the significant clinical problems such as face flush, chronic pain, foreign body granuloma, etc.  To date, ultrasonography, mammography, X-ray CT, MRI, and histological examination have been developed for the ingredient analysis of the augmentation materials.  The purpose of this study is to summarize these imaging of implant materials in order to predict the substances preoperatively. 

MATERIALS AND METHODS:104 patients who had complaints of the late complications after breast augmentations between 1971 and 2002 were examined.  Precise medical examination revealed that 64 of those received injectable materials, 36 of those bag prostheses and 4 received both of these materials for augmentation.  46 of these patients who underwent mammography, CT, and MRI from 1989 to 2002 were reviewed for this study. 

RESULTS:The representative characteristics of the imaging in each material are summarized in table listed below. 

Materials	Mammography	CT	MRI (T1/T2)
Silicone bag	Radiopaque	Radiopaque	Low/Iso
Saline bag	Radiolucent	Radiolucent	Iso/Low
Hydrogel bag	Radiolucent	Radiolucent	Low�`Iso/High
Cohesive silicone bag	Radiopaque	Radiolucent	Low/High
Hydrocarbon	Radiolucent	Radiolucent	Iso/Low
Injected fat	Radiolucent	Radiolucent	High/Iso

However, some of the injectable materials were difficulty in being identified because they are mostly composed of several substances including silicone and hydrocarbon. 

CONCLUSIONS:We found that (1) The ingredient of implant materials for breast augmentation can be predicted through mammography, CT, MRI preoperatively and (2) These imaging of implant materials play an important role on planning surgical procedures.  In addition, further analysis such as postoperative chemical analysis may also be necessary for supporting above these findings.