HIGH-RESOLUTION 25-MEGAHERTZ ULTRASONOGRAPHY OF THE GASTROINTESTINAL WALL - HISTOLOGIC CORRELATES

High-frequency ultrasonography (25 MHZ) with histologic correlation wa s used to examine surgical specimens from the gastrointestinal tract. Although the stomach, colon, and rectum demonstrated the usual five-la yered appearance, we found that the esophagus had additional layers wh en imaged with the high-resolution probe. These layers correspond to t he following: (1) superficial epithelium, (2) deep epithelium, (3) lam ina propria plus the acoustic interface echo between the lamina propri a and muscularis mucosa, and (4) muscularis mucosa minus the acoustic interface echo between the lamina propria and muscularis mucosa. This pattern is not found in regions of the gastrointestinal tract where th e muscularis mucosa is relatively thin compared with the axial resolut ion of the ultrasound system. These results suggest that within the es ophagus additional structural information may be obtained when higher- resolution ultrasound systems are used.