Acoustic Radiation Force Impulse quantitative elastography: a new noninvasive technique for the evaluation of parotid glands. A preliminary study in controls and in patients with irradiated nasopharyngeal carcinoma.
OBJECTIVE
We aim to define the values of the shear wave velocity (SWV) in the normal parotid glands (PG) and to identify the modifications of tissue stiffness in patients with irradiated nasopharyngeal carcinoma.


METHODS
Sixty normal parotid glands pertaining to 30 healthy volunteers and 40 pathological parotid glands pertaining to 20 patients who had had underwent radiation therapy for nasopharyngeal carcinoma were included in this study. The patients underwent a B mode ultrasonography examination and the volume of the parotid gland was determined. A subsequent Acoustic Radiation Forde Impulse Imaging (ARFI) examination was performed and the SWV were determined for the central and the periphery of the glandular parenchyma.


RESULTS
The mean volume of the gland in the volunteers' group (12.02+/-0.6 ml) was significantly higher than in the group of patients who underwent radiation therapy (10.3+/-0.74 ml) (p<0.0001). The SWV values in the normal group were lower compared to the patients group (1.54+/-0.6 m/s vs. 1.76+/-0.73 m/s, p<0.0001).


CONCLUSIONS
Elastography using the ARFI technique constitutes an objective method used for the evaluation of glandular stiffness in both normal and post radiotherapy glands. The SWV values determined in patients who underwent head and neck radiotherapy are increased, indicating a greater tissue stiffness thereby implying a structural transformation of the glandular parenchyma.
Department of Preventive Dentistry, "Iuliu Hatieganu" University of Medicine and Pharmacy, Cluj Napoca, Romania.
Iulia
I
Badea
Imaging Department, "O. Fodor" Institute of Gastroenterology and Hepatology, "Iuliu Hatieganu" University of Medicine and Pharmacy, Cluj Napoca, Romania. tamas-szora.attila@umfcluj.ro.
Attila
A
Tamas-Szora
Department of Mathematics, Faculty of Mathematics and Informatics, Babas-Bolyai University, Cluj Napoca, Romania.
Ioana
I
Chiorean
Department of Histology, "Iuliu Hatiegenu" University of Medicine and Pharmacy,Cluj Napoca, Romania.
Maria
M
Crisan
Department of Radiotherapy, Oncologic Institute "Prof. Dr. Ion Chiricuta", Cluj Napoca, Romania.
Elisabeta
E
Ciuleanu
Departemnt of Maxillofacial Surgery, "Iuliu Hatieganu" University of Medicine and Pharmacy, Cluj Napoca, Romania.
Grigore
G
Baciut
Department of Preventive Dentistry, "Iuliu Hatieganu" University of Medicine and Pharmacy, Cluj Napoca, Romania.
Mindra
M
Badea
D000328:Adult; D002277:Carcinoma; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000532:radiotherapy*; D010306:Parotid Gland / Q000000981:diagnostic imaging* / Q000528:radiation effects*; D011446:Prospective Studies; D012472:Salivation