MR imaging of the head and neck

The purpose of this paper is to describe current imaging protocols for MR imaging of the head and neck region and to define results and clinical impact. Depending on the clinical question, different MRI protocols are presented for imaging of the head and neck. The appearance of different pathologic findings on imaging studies and how adapted imaging protocols help to improve differential diagnosis is discussed. In summary, MRI is the method of choice for imaging of the head and neck.     

Value of retrospective image fusion of F-FDG PET and MRI for preoperative staging of head and neck cancer: Comparison with PET/CT and contrast-enhanced neck MRI

Purpose

To assess the clinical value of retrospective image fusion of neck MRI and ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) PET for locoregional extension and nodal staging of neck cancer.

Materials and methods

Thirty patients with carcinoma of the oral cavity or hypopharynx underwent PET/CT and contrast-enhanced neck MRI for initial staging before surgery including primary tumor resection and neck dissection. Diagnostic performance of PET/CT, MRI, and retrospective image fusion of PET and MRI (fused PET/MRI) for assessment of the extent of the primary tumor (T stage) and metastasis to regional lymph nodes (N stage) was evaluated.

Results

Accuracy for T status was 87% for fused PET/MRI and 90% for MRI, thus proving significantly superior to PET/CT, which had an accuracy of 67% (p = 0.041 and p = 0.023, respectively). Accuracy for N status was 77% for both fused PET/MRI and PET/CT, being superior to MRI, which had an accuracy of 63%, although the difference was not significant (p = 0.13). On a per-level basis, the sensitivity, specificity and accuracy for detection of nodal metastasis were 77%, 96% and 93% for both fused PET/MRI and PET/CT, compared with 49%, 99% and 91% for MRI, respectively. The differences for sensitivity (p = 0.0026) and accuracy (p = 0.041) were significant.

Conclusion

Fused PET/MRI combining the individual advantages of MRI and PET is a valuable technique for assessment of staging neck cancer.     

Cross-sectional imaging in non-melanoma skin cancer of the head and neck

AIM: To investigate in head and neck non-melanoma skin cancers (NMSCs) the accuracy of cross-sectional imaging for detection of local tumour extent, recurrent tumour and prediction of patient outcome. METHODS: This retrospective study included 33 NMSC patients (22 men, 11 women, median age 69 years) with 8 primary and 25 suspected recurrent tumours. The findings of magnetic resonance imaging (MRI) and computed tomography (CT) were compared with histopathology, and accuracy of MRI or CT in detecting local recurrence was determined. Extent of disease on imaging was compared with patient outcome assessed by clinical follow-up to a mean of 26.4 months. RESULTS: Lesions were identified in 29 patients, whose mean disease-free survival (DFS) was 25.5 months. In 4 of these cases, where imaging showed no invasion of deep structures, DFS was 56 months. In the other 25 cases DFS was 20.6 months, irrespective of treatment but varying with site of involvement. Of 19 patients treated with surgery, imaging of 16 showed deep invasion, which was confirmed at histology in 15 (93.7% accuracy), and 3 had superficial tumours on imaging all confirmed by histology (100% accuracy). Imaging accuracy for identifying recurrent tumour was 96% (24 of 25 patients). CONCLUSION: In NMSC, cross-sectional imaging accurately identifies tumour extent and local recurrence. The extent of disease and invasion of deeper structures predicts patient outcome.     

Characterization of pediatric head and neck masses with diffusion-weighted MR imaging

We aimed to assess the clinical usefulness of the ADCs calculated from diffusion-weighted echo-planar MR images in the characterization of pediatric head and neck masses. This study included 78 pediatric patients (46 boys and 32 girls aged 3 months–15 years, mean 6 years) with head and neck mass. Routine MR imaging and diffusion-weighted MR imaging were done on a 1.5-T MR unit using a single-shot echo-planar imaging (EPI) with a b factor of 0.500 and 1,000 s mm⁻². The ADC value was calculated. The mean ADC values of the malignant tumours, benign solid masses and cystic lesions were (0.93 ± 0.18) × 10⁻³, (1.57 ± 0.26) × 10^–3 and (2.01 ± 0.21 )× 10^–3 mm² s⁻¹, respectively. The difference in ADC value between the malignant tumours and benign lesions was statistically significant (p < 0.001). When an apparent diffusion coefficient value of 1.25 × 10^–3 mm² s⁻¹ was used as a threshold value for differentiating malignant from benign head and neck mass, the best results were obtained with an accuracy of 92.8%, sensitivity of 94.4%, specificity of 91.2%, positive predictive value of 91% and negative predictive value of 94.2%. Diffusion-weighted MR imaging is a new promising imaging approach that can be used for characterization of pediatric head and neck mass.     

Edema in the retropharyngeal space associated with head and neck tumors: CT imaging characteristics

To determine computed tomographic (CT) imaging characteristics of retropharygeal edema, we reviewed CT images in 18 patients with head and neck tumors. Retropharyngeal edema spread craniocaudally between soft palate and upper half of thyroid cartilage in all patients. No edema fluid extended above soft palate and below thyroid cartilage. Horizontally, it spread symmetrically in ten and asymmetrically in eight patients. Predominance in asymmetrical retropharyngeal edema was found on the same side as that of unilateral predominance both in lymph nodes enlargement and jugular vein stenosis/occlusion. All patients had edema also in other cervical spaces. Edema of retropharyngeal and other spaces fluctuated synchronously. In 14 patients, as primary lesion and/or cervical lymph nodes regressed, retropharyngeal edema disappeared or decreased. Retropharyngeal edema had some imaging characteristics. With knowledge of that, we could avoid diagnostic confusion when evaluating head and neck CT images.     

放射性125I粒子植入治疗头颈部肿瘤

目的 探讨超声或CT引导下放射性^125I粒子组织间植入治疗头颈部肿瘤的技术可行性和近期疗效。方法 40例头颈部癌和转移癌患者。4例采用全身麻醉，在CT引导下行^125I粒子植入术；36例采用局部麻醉，行超声引导下^125I粒子植入术。粒子针平行排列，间距1～1．5cm，原发肿瘤植入靶体积影像学边界外放lcm，转移瘤植入靶体积为影像学边界。粒子间距1cm。肿瘤周边匹配剂量（matched peripheral dose，MPD）90～145Gy，每颗粒子活度0．40～0．70mCi，每个病灶植入3～84颗粒子。5例患者术后1周加外放疗，每次200cGy，总剂量45～50Gy。术后24h拍头颈正侧位平片或CT，行质量验证。术后24～48h拍胸部x线片了解有无粒子移位或游走。结果 随访3～33月，10例舌癌3例完全缓解，3例部分缓解，3例稳定，1例进展；2例颈部淋巴结转移的患者经粒子治疗后完全缓解，局部控制率为60％，中位生存期11个月，1年和2年生存率分别为87．50％和35％。14例头颈部癌粒子治疗后，局部控制率为76．47％，中位生存期9个月，1年和2年生存率为66．08％和24％。16例头颈部转移癌粒子治疗后，局部控制率95．23％，中位生存期9个月，1年和2年生存率为54．55％和32．73％。没有1例发生严重的皮肤反应。结论 放射性^125I粒子粒子植入治疗头颈部癌疗效确切，尤其是为那些手术后或放疗复发患者提供了一种新的、可行的、安全和微创治疗手段。     

基于锥形束CT的头颈部肿瘤在线与离线结合图像引导放疗的研究

目的 分析锥形束CT(CBCT)在线摆位校正与离线自适应校正在减小头颈部肿瘤临床靶区(CTV)外放,从而减轻正常组织并发症中的作用.方法 16例行三维适形放疗的头颈部癌症患者入组.分次放疗前后均行在线CBCT扫描1次,并与计划CT图像配准,记录各个方向的配准差值.放疗前后的配准差值分别作为放疗分次间误差和分次内误差,用于计算每例患者的系统误差和随机误差.利用CTV外放计算公式,计算在线校正前后CTV外放;以0.5 mm为允许的最大残余系统误差,计算离线校正系统摆位误差后CTV外放.结果 未经在线校正,左右、头脚和前后方向上群体化CTV外放分别为5.7mm、5.6 mm和7.3 mm;每分次放疗均行在线校正,3个方向上群体化CTV外放分别为1.7 mm、1.7 mm和2.3 mm;对系统摆位误差进行离线自适应校正,3个方向上群体化CTV外放分别为2.7 mm、2.5mm和3.6 mm.结论 基于CBCT图像分析的在线校正和离线自适应校正均能明显减小摆位误差,有助于缩小CTV外放,并有望减轻正常组织并发症.     

基于锥形束CT的头颈部肿瘤在线与离线结合图像引导放疗的研究

目的 分析锥形束CT(CBCT)在线摆位校正与离线自适应校正在减小头颈部肿瘤临床靶区(CTV)外放,从而减轻正常组织并发症中的作用.方法 16例行三维适形放疗的头颈部癌症患者入组.分次放疗前后均行在线CBCT扫描1次,并与计划CT图像配准,记录各个方向的配准差值.放疗前后的配准差值分别作为放疗分次间误差和分次内误差,用于计算每例患者的系统误差和随机误差.利用CTV外放计算公式,计算在线校正前后CTV外放;以0.5 mm为允许的最大残余系统误差,计算离线校正系统摆位误差后CTV外放.结果 未经在线校正,左右、头脚和前后方向上群体化CTV外放分别为5.7mm、5.6 mm和7.3 mm;每分次放疗均行在线校正,3个方向上群体化CTV外放分别为1.7 mm、1.7 mm和2.3 mm;对系统摆位误差进行离线自适应校正,3个方向上群体化CTV外放分别为2.7 mm、2.5mm和3.6 mm.结论 基于CBCT图像分析的在线校正和离线自适应校正均能明显减小摆位误差,有助于缩小CTV外放,并有望减轻正常组织并发症.     

基于锥形束CT的头颈部肿瘤在线与离线结合图像引导放疗的研究

目的 分析锥形束CT(CBCT)在线摆位校正与离线自适应校正在减小头颈部肿瘤临床靶区(CTV)外放,从而减轻正常组织并发症中的作用.方法 16例行三维适形放疗的头颈部癌症患者入组.分次放疗前后均行在线CBCT扫描1次,并与计划CT图像配准,记录各个方向的配准差值.放疗前后的配准差值分别作为放疗分次间误差和分次内误差,用于计算每例患者的系统误差和随机误差.利用CTV外放计算公式,计算在线校正前后CTV外放;以0.5 mm为允许的最大残余系统误差,计算离线校正系统摆位误差后CTV外放.结果 未经在线校正,左右、头脚和前后方向上群体化CTV外放分别为5.7mm、5.6 mm和7.3 mm;每分次放疗均行在线校正,3个方向上群体化CTV外放分别为1.7 mm、1.7 mm和2.3 mm;对系统摆位误差进行离线自适应校正,3个方向上群体化CTV外放分别为2.7 mm、2.5mm和3.6 mm.结论 基于CBCT图像分析的在线校正和离线自适应校正均能明显减小摆位误差,有助于缩小CTV外放,并有望减轻正常组织并发症.     

基于锥形束CT的头颈部肿瘤在线与离线结合图像引导放疗的研究

目的 分析锥形束CT(CBCT)在线摆位校正与离线自适应校正在减小头颈部肿瘤临床靶区(CTV)外放,从而减轻正常组织并发症中的作用.方法 16例行三维适形放疗的头颈部癌症患者入组.分次放疗前后均行在线CBCT扫描1次,并与计划CT图像配准,记录各个方向的配准差值.放疗前后的配准差值分别作为放疗分次间误差和分次内误差,用于计算每例患者的系统误差和随机误差.利用CTV外放计算公式,计算在线校正前后CTV外放;以0.5 mm为允许的最大残余系统误差,计算离线校正系统摆位误差后CTV外放.结果 未经在线校正,左右、头脚和前后方向上群体化CTV外放分别为5.7mm、5.6 mm和7.3 mm;每分次放疗均行在线校正,3个方向上群体化CTV外放分别为1.7 mm、1.7 mm和2.3 mm;对系统摆位误差进行离线自适应校正,3个方向上群体化CTV外放分别为2.7 mm、2.5mm和3.6 mm.结论 基于CBCT图像分析的在线校正和离线自适应校正均能明显减小摆位误差,有助于缩小CTV外放,并有望减轻正常组织并发症.     

基于锥形束CT的头颈部肿瘤在线与离线结合图像引导放疗的研究

目的 分析锥形束CT(CBCT)在线摆位校正与离线自适应校正在减小头颈部肿瘤临床靶区(CTV)外放,从而减轻正常组织并发症中的作用.方法 16例行三维适形放疗的头颈部癌症患者入组.分次放疗前后均行在线CBCT扫描1次,并与计划CT图像配准,记录各个方向的配准差值.放疗前后的配准差值分别作为放疗分次间误差和分次内误差,用于计算每例患者的系统误差和随机误差.利用CTV外放计算公式,计算在线校正前后CTV外放;以0.5 mm为允许的最大残余系统误差,计算离线校正系统摆位误差后CTV外放.结果 未经在线校正,左右、头脚和前后方向上群体化CTV外放分别为5.7mm、5.6 mm和7.3 mm;每分次放疗均行在线校正,3个方向上群体化CTV外放分别为1.7 mm、1.7 mm和2.3 mm;对系统摆位误差进行离线自适应校正,3个方向上群体化CTV外放分别为2.7 mm、2.5mm和3.6 mm.结论 基于CBCT图像分析的在线校正和离线自适应校正均能明显减小摆位误差,有助于缩小CTV外放,并有望减轻正常组织并发症.     

基于锥形束CT的头颈部肿瘤在线与离线结合图像引导放疗的研究

目的 分析锥形束CT(CBCT)在线摆位校正与离线自适应校正在减小头颈部肿瘤临床靶区(CTV)外放,从而减轻正常组织并发症中的作用.方法 16例行三维适形放疗的头颈部癌症患者入组.分次放疗前后均行在线CBCT扫描1次,并与计划CT图像配准,记录各个方向的配准差值.放疗前后的配准差值分别作为放疗分次间误差和分次内误差,用于计算每例患者的系统误差和随机误差.利用CTV外放计算公式,计算在线校正前后CTV外放;以0.5 mm为允许的最大残余系统误差,计算离线校正系统摆位误差后CTV外放.结果 未经在线校正,左右、头脚和前后方向上群体化CTV外放分别为5.7mm、5.6 mm和7.3 mm;每分次放疗均行在线校正,3个方向上群体化CTV外放分别为1.7 mm、1.7 mm和2.3 mm;对系统摆位误差进行离线自适应校正,3个方向上群体化CTV外放分别为2.7 mm、2.5mm和3.6 mm.结论 基于CBCT图像分析的在线校正和离线自适应校正均能明显减小摆位误差,有助于缩小CTV外放,并有望减轻正常组织并发症.     

基于锥形束CT的头颈部肿瘤在线与离线结合图像引导放疗的研究

目的 分析锥形束CT(CBCT)在线摆位校正与离线自适应校正在减小头颈部肿瘤临床靶区(CTV)外放,从而减轻正常组织并发症中的作用.方法 16例行三维适形放疗的头颈部癌症患者入组.分次放疗前后均行在线CBCT扫描1次,并与计划CT图像配准,记录各个方向的配准差值.放疗前后的配准差值分别作为放疗分次间误差和分次内误差,用于计算每例患者的系统误差和随机误差.利用CTV外放计算公式,计算在线校正前后CTV外放;以0.5 mm为允许的最大残余系统误差,计算离线校正系统摆位误差后CTV外放.结果 未经在线校正,左右、头脚和前后方向上群体化CTV外放分别为5.7mm、5.6 mm和7.3 mm;每分次放疗均行在线校正,3个方向上群体化CTV外放分别为1.7 mm、1.7 mm和2.3 mm;对系统摆位误差进行离线自适应校正,3个方向上群体化CTV外放分别为2.7 mm、2.5mm和3.6 mm.结论 基于CBCT图像分析的在线校正和离线自适应校正均能明显减小摆位误差,有助于缩小CTV外放,并有望减轻正常组织并发症.     

基于锥形束CT的头颈部肿瘤在线与离线结合图像引导放疗的研究

目的 分析锥形束CT(CBCT)在线摆位校正与离线自适应校正在减小头颈部肿瘤临床靶区(CTV)外放,从而减轻正常组织并发症中的作用.方法 16例行三维适形放疗的头颈部癌症患者入组.分次放疗前后均行在线CBCT扫描1次,并与计划CT图像配准,记录各个方向的配准差值.放疗前后的配准差值分别作为放疗分次间误差和分次内误差,用于计算每例患者的系统误差和随机误差.利用CTV外放计算公式,计算在线校正前后CTV外放;以0.5 mm为允许的最大残余系统误差,计算离线校正系统摆位误差后CTV外放.结果 未经在线校正,左右、头脚和前后方向上群体化CTV外放分别为5.7mm、5.6 mm和7.3 mm;每分次放疗均行在线校正,3个方向上群体化CTV外放分别为1.7 mm、1.7 mm和2.3 mm;对系统摆位误差进行离线自适应校正,3个方向上群体化CTV外放分别为2.7 mm、2.5mm和3.6 mm.结论 基于CBCT图像分析的在线校正和离线自适应校正均能明显减小摆位误差,有助于缩小CTV外放,并有望减轻正常组织并发症.     

基于锥形束CT的头颈部肿瘤在线与离线结合图像引导放疗的研究

目的 分析锥形束CT(CBCT)在线摆位校正与离线自适应校正在减小头颈部肿瘤临床靶区(CTV)外放,从而减轻正常组织并发症中的作用.方法 16例行三维适形放疗的头颈部癌症患者入组.分次放疗前后均行在线CBCT扫描1次,并与计划CT图像配准,记录各个方向的配准差值.放疗前后的配准差值分别作为放疗分次间误差和分次内误差,用于计算每例患者的系统误差和随机误差.利用CTV外放计算公式,计算在线校正前后CTV外放;以0.5 mm为允许的最大残余系统误差,计算离线校正系统摆位误差后CTV外放.结果 未经在线校正,左右、头脚和前后方向上群体化CTV外放分别为5.7mm、5.6 mm和7.3 mm;每分次放疗均行在线校正,3个方向上群体化CTV外放分别为1.7 mm、1.7 mm和2.3 mm;对系统摆位误差进行离线自适应校正,3个方向上群体化CTV外放分别为2.7 mm、2.5mm和3.6 mm.结论 基于CBCT图像分析的在线校正和离线自适应校正均能明显减小摆位误差,有助于缩小CTV外放,并有望减轻正常组织并发症.     

基于锥形束CT的头颈部肿瘤在线与离线结合图像引导放疗的研究

目的 分析锥形束CT(CBCT)在线摆位校正与离线自适应校正在减小头颈部肿瘤临床靶区(CTV)外放,从而减轻正常组织并发症中的作用.方法 16例行三维适形放疗的头颈部癌症患者入组.分次放疗前后均行在线CBCT扫描1次,并与计划CT图像配准,记录各个方向的配准差值.放疗前后的配准差值分别作为放疗分次间误差和分次内误差,用于计算每例患者的系统误差和随机误差.利用CTV外放计算公式,计算在线校正前后CTV外放;以0.5 mm为允许的最大残余系统误差,计算离线校正系统摆位误差后CTV外放.结果 未经在线校正,左右、头脚和前后方向上群体化CTV外放分别为5.7mm、5.6 mm和7.3 mm;每分次放疗均行在线校正,3个方向上群体化CTV外放分别为1.7 mm、1.7 mm和2.3 mm;对系统摆位误差进行离线自适应校正,3个方向上群体化CTV外放分别为2.7 mm、2.5mm和3.6 mm.结论 基于CBCT图像分析的在线校正和离线自适应校正均能明显减小摆位误差,有助于缩小CTV外放,并有望减轻正常组织并发症.     

Evaluation of suspected local recurrence in head and neck cancer: a comparison between PET and PET/CT for biopsy proven lesions

Background

¹⁸F-FDG PET has a high accuracy for re-staging of head and neck cancer. The purpose of this study was to determine whether the diagnostic accuracy can be further improved with integrated PET/CT.

Materials and methods

Forty-nine patients with a mean age of 59 ± 18 years were studied retrospectively. Histo-pathological verification was available either from complete tumor resection with or without lymph node dissection (n = 27) or direct endoscopic biopsy (n = 16) or ultrasound guided biopsy (n = 6). Two reviewers blinded to the pathological findings read all PET images in consensus. An experienced radiologist was added for the interpretation of the PET/CT images.

Results

Tissue verification was available for 110 lesions in 49 patients. Sixty-seven lesions (61%) were biopsy positive and 43 (39%) were negative for malignant disease. PET and PET/CT showed an overall accuracy for cancer detection of 84 and 88% (p = 0.06), respectively. Sensitivity and specificity for PET were 78 and 93% versus 84 (p = NS) and 95% (p = NS) with PET/CT. A patient-by-patient analysis yielded a sensitivity, specificity and accuracy for PET of 80, 56 and 76%, compared to 88% (p = NS), 78% (p = NS) and 86% (p = 0.06) for PET/CT.

Conclusion

The results of this study indicate that PET/CT does not significantly improve the detection of recurrence of head and neck cancer. However, a trend towards improved accuracy was observed (p = 0.06).     

Morphological MRI criteria improve the detection of lymph node metastases in head and neck squamous cell carcinoma: multivariate logistic regression analysis of MRI features of cervical lymph nodes

The aim was to evaluate whether morphological criteria in addition to the size criterion results in better diagnostic performance of MRI for the detection of cervical lymph node metastases in patients with head and neck squamous cell carcinoma (HNSCC). Two radiologists evaluated 44 consecutive patients in which lymph node characteristics were assessed with histopathological correlation as gold standard. Assessed criteria were the short axial diameter and morphological criteria such as border irregularity and homogeneity of signal intensity on T2-weighted and contrast-enhanced T1-weighted images. Multivariate logistic regression analysis was performed: diagnostic odds ratios (DOR) with 95% confidence intervals (95% CI) and areas under the curve (AUCs) of receiver-operating characteristic (ROC) curves were determined. Border irregularity and heterogeneity of signal intensity on T₂-weighted images showed significantly increased DORs. AUCs increased from 0.67 (95% CI: 0.61–0.73) using size only to 0.81 (95% CI: 0.75–0.87) using all four criteria for observer 1 and from 0.68 (95% CI: 0.62–0.74) to 0.96 (95% CI: 0.94–0.98) for observer 2 (p < 0.001). This study demonstrated that the morphological criteria border irregularity and heterogeneity of signal intensity on T2-weighted images in addition to size significantly improved the detection of cervical lymph nodes metastases.     

头颈部血管畸形的磁共振成像特征

明确头颈部血管畸形的磁共振影像特征。材料与方法对５１例头颈部血管畸形患者进行磁共振检查,其中静脉畸形３２例,毛细血管畸形３例,混合性血管畸形３例,动静脉畸形１３例。磁共振扫描仪为Ｐｈｉｌｐｓ ＧｙｒｏｓｃａｎＮＴ１．０Ｔ,常规进行Ｔ１及Ｔ２ＷＩ检查。结果静脉畸形为Ｔ２ＷＩ上高信号,均匀的团块影;毛细血管畸形在ＭＲＩ上不能显示;动静脉畸形为不规则的蜂窝状流空血管巢及曲张的营养血管,Ｔ１及Ｔ２ＷＩ都表     

头颈部嗜酸性淋巴肉芽肿的影像及病理学分析

目的 探讨头颈部嗜酸性淋巴肉芽肿(KD)的影像表现及病理特征,以提高对该病的术前诊断率。方法 回顾性分析8例经病理证实的头颈部KD患者的临床影像及病理表现。结果 8例KD患者中,单发与多发各4例;部位:腮腺6例、口底(颌下腺区)1例、眼睑1例,其中2例累及腹股沟。CT和MRI征象:①累及腮腺者(4例):患侧腮腺、面部弥漫性增大,结节边界欠清或较清,密度略高于腮腺,T1加权像多为等信号,T2加权像信号则多为等、低信号,增强扫描有不同程度强化;②累及头颈部其他部位(如颌下腺区、眼睑等)者:病变密度、信号、强化程度亦与累及腮腺者类似,但可有周围组织的受累(如颅骨);③周围淋巴结常不同程度受累、增大,密度、信号均匀,边界清楚,无坏死,无融合;往往累及局部皮下组织,邻近皮肤增厚。病理:KD组织成分基本一致,均由淋巴细胞、嗜酸性粒细胞、小血管和纤维组织以不同比例组成。结论 KD有一定的好发部位和临床特点,结合影像学检查与病理分析,可大大提高其术前诊断的正确率。