Abstract
For the differential diagnosis of tumors, we studied the internal echo histograms of 20 head and neck tumors with a 7.5MHz probe; the width of the histograms was of 0%, 25%, 50%, 75% frequency and the echo level was of maximum shades of grey.
1) An analysis of the width of the histograms showed three patterns: mountain type with a narrow base for normal tissue, mountain type with a wide base for benign tumors and bell type with wide base and sides for malignant tumors.
2) There was no statistically significant difference in the echo level of the maximum shades of grey between benign and malignant tumors.
