Mısırlıoglu Melda, Nalcaci Rana, Adisen Mehmet Zahit, Yardımcı Selmi
Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Kırıkkale University, Kırıkkale, Turkey.
Imaging Sci Dent. 2013 Sep;43(3):163-9. doi: 10.5624/isd.2013.43.3.163. Epub 2013 Sep 23.
Tonsilloliths are calcifications found in the crypts of the palatal tonsils and can be detected on routine panoramic examinations. This study was performed to highlight the benefits of cone-beam computed tomography (CBCT) in the diagnosis of tonsilloliths appearing bilaterally on panoramic radiographs.
The sample group consisted of 7 patients who had bilateral radiopaque lesions at the area of the ascending ramus on panoramic radiographs. CBCT images for every patient were obtained from both sides of the jaw to determine the exact locations of the lesions and to rule out other calcifications. The calcifications were evaluated on the CBCT images using Ez3D2009 software. Additionally, the obtained images in DICOM format were transferred to ITK SNAP 2.4.0 pc software for semiautomatic segmentation. Segmentation was performed using contrast differences between the soft tissues and calcifications on grayscale images, and the volume in mm(3) of the segmented three dimensional models were obtained.
CBCT scans revealed that what appeared on panoramic radiographs as bilateral images were in fact unilateral lesions in 2 cases. The total volume of the calcifications ranged from 7.92 to 302.5mm(3). The patients with bilaterally multiple and large calcifications were found to be symptomatic.
The cases provided the evidence that tonsilloliths should be considered in the differential diagnosis of radiopaque masses involving the mandibular ramus, and they highlight the need for a CBCT scan to differentiate pseudo- or ghost images from true bilateral pathologies.
扁桃体结石是在腭扁桃体隐窝中发现的钙化灶,可在常规全景检查中检测到。本研究旨在突出锥形束计算机断层扫描(CBCT)在诊断全景X线片上双侧出现的扁桃体结石中的作用。
样本组由7例在全景X线片上升支区域有双侧不透光病变的患者组成。为每位患者从颌骨两侧获取CBCT图像,以确定病变的确切位置并排除其他钙化灶。使用Ez3D2009软件在CBCT图像上评估钙化灶。此外,将获取的DICOM格式图像传输到ITK SNAP 2.4.0个人电脑软件进行半自动分割。利用灰度图像上软组织和钙化灶之间的对比度差异进行分割,获得分割后的三维模型的体积(单位为mm³)。
CBCT扫描显示,在全景X线片上表现为双侧影像的病变,实际上在2例中为单侧病变。钙化灶的总体积在7.92至302.5mm³之间。发现双侧有多个大钙化灶的患者有症状。
这些病例证明,在鉴别涉及下颌升支的不透光肿物时应考虑扁桃体结石,并且突出了需要进行CBCT扫描以区分伪像或幻影图像与真正的双侧病变。