螺旋CT对腮腺恶性肿瘤的诊断价值

Diagnostic value of SCT to malignant parotid gland tumors

目的:分析腮腺恶性肿瘤的CT表现,以及MPR后处理图像对提高诊断率的价值。方法:分析经我院于术病理证实的腮腺原发恶性肿瘤2 2例,包括粘液表皮样癌9例,腺癌及鳞状细胞癌各4例,腺泡细胞癌3例,恶性混合瘤2例。结果:2 2例中肿物呈圆形及椭圆形8例,不规则形14例,边缘清楚9例(在MPR图像上总能发现边缘毛糙、周围脂肪受侵) ,边缘不清楚13例,肿瘤有不同程度的向周围组织浸润。增强扫描显示肿瘤均有不同程度的强化,其中18例明显强化,薄环状强化伴中央大片低密度坏死5例,肿块呈不规则型强化17例。颈部淋巴结转移11例。临床表现有面神经受累9例,其中6例横断位上下颌后静脉增强扫描显示不清;3例下颌后静脉较清晰可见,但在MPR图像上显示受压变形、移位。结论:面神经受累为腮腺恶性肿瘤的临床特点,肿块边缘不规则、边界不清、有明显强化、内部密度不均匀以及颈部淋巴结肿大为原发腮腺恶性肿瘤影像学特点。

Objective:To analyze CT appearances of malignant parotid gland carcinoma and the value of MPR in elevating diagnostic rate.Methods:22 cases of primary malignant parotid gland tumors proved surgically and pathologically were analyzed , including myxoepidermocarcinoma (n=9), adenocarcinoma (n=4), squamous cell carcinoma (n=4), acinus cell carcinoma (n=3), malignant mixed tumors (n=2).Results:In 22 cases, shape of the tumors were round and oval (n=8), irregular (n=14); the margin was clear in 9 cases (with rough margin and adjacent fat invasion on MPR); the margin was not clear in 13 cases, with invasion to the adjacent tissue variously. On enhanced images, the tumors were enhaced obviously (n=18), ring-like with thin wall and patchy necrosis (n=5), irregularly (n=17). Cervical lymph node metastasis was found in 11 cases.Facial nerve was involved clinically in 9 cases.Posterior mandibular vein was not clear on trnsverse enhanced scanning in 6 cases, it was clear in 3 cases but appeared being distorted and displaced on MPR.Conclusion:Facial nerve involved was clinical character of malignant parotid gland tumors, irregular margin, rough boundary, enhanced obviously, inner inhomogeneous density, and swollen cervical lymph nodes were radiological characters of primary parotid gland tumors.