Michiko Nakajima MD, PhD, Presenter: Nothing to Disclose

Yoshio Kiyohara, Abstract Co-Author: Nothing to Disclose

Masao Shimizu MD, Abstract Co-Author: Nothing to Disclose

Masahito Taguchi MD,PHD, Abstract Co-Author: Nothing to Disclose

Tetsuya Tsuchida MD, PhD, Abstract Co-Author: Nothing to Disclose

Masayuki Kobayashi MD, PhD, Abstract Co-Author: Nothing to Disclose

To evaluate the diagnostic performance of real-time freehand elastography by using the extended combined autocorrelation method (CAM)　and color （power)Doppler sonography to differentiate benign from malignant skin lesions.

Studies were made on the 40 cases of benign skin tumors and 40 cases of malignancy. In Elastographic study , we used EUB 8500 system. During our conventional examination, we obtained B-mode images first, and then color Doppler US was performed. One the same day, we next obtained elasticity images as motion images. we assigned each image an elasticity score on a five point scores. Score 1: the entire lesion was evenly shaded green. Score 2a: the lesion shows mosaic of green and blue. and the thing of green predominance. Score 2b:the lesion shows mosaic of green and blue. and the thing of blue predominance. Score 3:The central part of the hypoechoic lesion is blue and the peripheral part of the lesion is green. Score 4: The entire lesion is blue. Score 5: Both the entire lesion and its surrounding area are blue. In color Doppler imaging, We classified 4 types. Type 1: color signal is not detected in the lesions. Type 2: Single vascular pole in the lesions is detected Type 3: A lot of straight internal vessels and branches are detected. Type 4:A lot of tortuous internal vessels and branches are detected. We used pathologic diagnosis as the reference standard.

In color Doppler examination, 31 benign lesions were showed type 1 or 2, whereas the malignant tumors were showed type 3 or 4. But 9 benign lesions were showed type 3 or 4, namely they were hypervascular tumors as same as malignancy. In elastographic examination all benign lesions were showed score 1 or 2a and all malignant tumors were showed score 2b or above 2b. Moreover about within 2 cm malignant tumors(36 cases) , they were all showed score3,4 and 5.

It is useful for differential diagnosis of skin tumors to use elastography combined color Doppler sonography.

Elastograly study is safety and can demonstrate eloquent areas of malignant skin tumors and this exam is recommended when the underlying cause of such a lesion is unclear.

Nakajima, M, Kiyohara, Y, Shimizu, M, Taguchi, M, Tsuchida, T, Kobayashi, M, Elastographic and Color Doppler Diagnosis of Skin Tumors.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5008520.html