Normal Echo-Anatomy and Pathological US Findings in Rheumatology: Diagnostic Added Value of Elastography

Abstracts Results: The maximum and mean Young’s modulus of muscle (maximum: p 5 0.02; mean: p , 0.0001) and tendon (maximum: p , 0.0001; mean: p , 0.0001) were significantly different when different transducer pressures were applied. The maximum Young’s modulus of muscle (p , 0.0001) and tendon (p , 0.0001) was significantly different when different sizes of ROI were used. However, the mean Young’s modulus of muscle (p 5 0.88) and tendon (p 5 0.52) was not significantly different when different sizes of ROI were used. Conclusion: This study provides information about the maximum and mean Young’s modulus of muscle and tendon and variations between different transducer’s pressures and ROI’s sizes. P 263 ee Benign or Malignant? In Soft Tissue Tumor, Can You Suggest Unsuspected Results in the Ultrasound Images? J. B. Koo,1 D. J. Shin,1 D. Jung2 1 Radiology, Dongguk University Ilsan Hospital, Goyang/KR, 2 Radiology, Healthcare System Gangnam Center, Seoul National University Hospital, Seoul/KR Learning Objectives: Ultrasonography (USG) is fast and inexpensive. Also, it is an ideal method for differentiating solid and cystic lesions. The role of USG is to provide information about the extent of the mass, its nature and its relationship to the surrounding structures. USG cannot differentiate benign from malignant tumors exactly, but findings of the possibility of malignancy on USG are still an important and interesting subject to the radiologist. Background: Susggestive characteristics of benign and malignant soft tissue tumor on USG. Unsuspected result of two cases of malignant soft tissue tumor Imaging Findings or Procedure Details: USG reveals two welldefined small ovoid low echoic masses in the subcutaneous layer of the left thigh. There was no evidence of invasion to perilesional structures. Color Doppler USG shows no definite vascularity. These findings are features of benign tumor. But, the pathological diagnosis was malignant fibrohistiocytoma. Conclusion: Nevertheless, we have to know each characteristic of benign and malignant tumor. However, inapplicapable cases, such as two unsuspected cases mentioned above, can exist. Therefore, the final diagnosis must be confined to histologic results of core needle biopsy or open biopsy. P 264 ee Normal Echo-Anatomy and Pathological US Findings in Rheumatology: Diagnostic Added Value of Elastography E. Mastorakou,1 I. Theotokas,2 A. Plagou,2 J. Ruci,3 P. S. Zoumpoulis2 1 Ultrasound, Onaseio Hospital, Kallithea/GR, 2Ultrasound, Diagnostic Echotomography SA, Kifissia/GR, 3Klinika Ungjillizimi, Tirana/AL Learning Objectives: To evaluate the findings of US and color Doppler in rheumatic disease and estimate the diagnostic value of elastography. Background: We studied 12 cases of osteoarthritis, 8 of rheumatoid arthritis, 11 cases of seronegative spondylarthritis, 8 cases of crystalrelated orthropathies, 7 cases suffering from metabolic disease, 6 cases of synovial osteo-chondromatosis, 4 cases of septic arthritis and 8 cases of post-traumatic etiology. Imaging Findings or Procedure Details: Point effusion, synovial proliferation, osteopathies, bone erosions and tendon involvement were retained as the main echo-morphologic features with different US and shear wave elastography (SWE) expression of those pathologies. SW elastography has a significant added value to the diagnosis of synovial proliferation and tendon involvement. Conclusion: US is a self-obtained method for the imaging assessment of small joints adding pathologic features in rheumatologic disease. SW

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elastography adds specific features of stiffness of tisues regarding synovial profileration and tendon involvement. P 265 se Sonography Using the Waterbath Method for the Evaluation of Superficial Lesion in Children J. H. Yoo,1 M. J. Yi,2 R. Krishnamurthy3 1 Department of Radiology, Ewha Womans University, School of Medicine, Seoul/KR, 2Radiology, 21th Century Hospital, Seoul/KR, 3 Diagnostic Imaging, Texas childrens Hospital, Houston, TX/US Purpose: Sonographic evaluation of superficial lesion in children can be indicated in the presence of foreign body, infection, vascular malformation, trauma, and evaluation of soft tissue nodule and masses. Sonography is a very useful method for evaluation of superficial structure in children. However, there are several limitations because the lesion has small field of view, easy compressed lesion by the transducer, noncooperation, and motion during the study. Waterbath method of sonography overcomes those limitations. We present our experiences of waterbath method of superficial sonography in 14 pediatric patients. Material & Methods: Fourteen patients included sonography applied waterbath method for the evaluation of superficial lesions. Mean age was 4yrs (6month to 10yr old). Lesions were located in 4 cases of foot and ankle, 4 of finger and nail, 2 legs and 2 forearm lesions, 2 buttock lesions. Results: Waterbath technique was superior to the standard technique for depiction of shallow skin ulcers, subcutaneous masses, osteomyelitis, foreign body and vascular lesions. In Raynaud’s disease, varying temperature of the waterbath reproduced the skin changes of Raynaud’s phenomenon. Reduced compression of the superficial structures led to the diagnosis of a subcutaneous AVM. Conclusion: Waterbath technique is a very helpful method for the evaluation of superficial sonography of children, especially for the evaluation of small joint and painful lesion. It improves image quality and patients’ comfort as well as provides diagnostic information. It will be an important technique for the superficial sonography.

Neuro P 266 se Investigations of Neurophysiology in Human Health and Disease: Effects of Mental Arithmetic and Music on EEG M. Mitra School of Biomedical Sciences, University of Nottingham, Nottingham/UK Purpose: A study investigating the effects of mental arithmetic and classical music on EEGs using new ADI equipment. Material & Methods: EEG and heart rate were recorded from 17 healthy undergraduates during eye opening, mental arithmetic tasks and while listening to classical music, using closed eyes as the control. The EEG from the left frontopolar-occipital (O1-Fp1) and parietal (P8-P7) bipolar electrode positions was filtered into frequency bands delta (0.1-3.5Hz), theta (4-7.5Hz), alpha (8-13Hz), beta (14-30Hz) and gamma (30-50Hz) using LabChart7 software for analysis. Results: Eye opening showed a significant decrease in alpha activity. The addition arithmetic task showed a significant decrease in alpha amplitude (30.6% in O1-Fp1 and 27.4% in P8-P7) and power (3.5% in O1-Fp1 and 2.5% in P8-P7). Similarly, the multiplication arithmetic task showed a significant decrease in alpha amplitude (33.9% in O1-Fp1 and 29% in P8-P7) and power (2.1% in O1-Fp1 and 3.1% in P8-P7). Furthermore, both arithmetic tasks showed increased heart rate. Listening to classical music decreased the beta power (1.5% in O1-