Radiographic differentiation of mediastinal versus pulmonary masses in dogs and cats can be challenging

犬猫X 线片上的纵膈肿物和肺肿物的鉴别是具有挑战性的

翻译 by / 高健

Abstract 摘要

The ability to differentiate thoracic masses of mediastinal and pulmonary origins is often confounded by their complex spatial relationship. The objectives of this retrospective, observational cross‐sectional study were to assess radiographic differentiation of mediastinal versus pulmonary masses, and to determine if there are any correlations with specific radiographic findings. Thoracic radiographs of 75 dogs and cats with mediastinal and/or pulmonary masses identified on CT were reviewed. Radiographic studies were anonymized, randomized, and reviewed twice by three reviewers. Reviewers categorized the origin of each mass(es) as mediastinal, pulmonary, or both. On the second review, the presence or absence of 21 different radiographic findings was recorded for each mass. Agreement between the radiographic and CT categorization of mass origin, as well as inter‐ and intraobserver agreement, was calculated. Overall agreement between radiographs and CT was moderate for both mediastinal (68.6%) and pulmonary masses (63%). Overall, interobserver agreement was moderate (κ = 0.50‐0.74), with moderate to strong intraobserver agreement (κ = 0.58‐0.93). Masses within the mediastinum were significantly more likely to displace other mediastinal structures. Alternatively, masses lateral to midline and in the caudal thorax were found to be significantly positively correlated with a pulmonary origin. The results of this study highlight the limitations of radiography for differentiation of mediastinal and pulmonary masses, with mass location and displacement of other mediastinal structures potentially useful for radiographic findings that may help improve accuracy.

鉴别纵隔肿物和肺源性肿物的能力常常被它们复杂的空间关系所混淆。

这项回顾性、观察性横断面研究的目的是

评估纵隔肿物和肺肿物的X线片的鉴别，

并确定其与特定的影像学表现是否存在相关性。

我们回顾了75只犬猫在CT上发现的纵膈肿物和/或肺肿物的胸片。

影像学研究是匿名的，随机的，由三位阅片员回顾两次。

阅片员将每个肿物的来源分为纵隔肿物、肺肿物或都有。

在第二次回顾中，记录了每个肿物的21种不同的x线表现的存在或不存在。

我们计算了影像学和CT对肿物来源分类的一致性，以及观察者间和观察者内的一致性。

纵隔肿物(68.6%)和肺肿物(63%)的X线片和CT的总体一致性中等。

总的来说，观察者间的一致性是中等的(κ= 0.50-0.74),

观察者内的一致性是中等至高度的(κ= 0.58-0.93)。

纵隔内的肿物明显更有可能使其他纵隔结构移位。

另外，在中线外侧和后侧胸腔发现肿物与肺起源呈显著正相关。

本研究的结果强调了X线片鉴别纵隔肿物和肺肿物的局限性，

肿物的位置和其他纵隔结构的移位对于X线的发现可能有助于提高准确性。

图 FIGURE 1

Left lateral (A) and ventrodorsal (B) thoracic radiographs and transverse postcontrast CT image (C) in a soft tissue window (window width 290 HU, window level 45 HU) at the level of the fourth thoracic vertebra of a 12‐year‐old female spayed Airedale terrier with a cranial mediastinal mass diagnosed as a thymic squamous cell carcinoma on surgical biopsy. Note the dorsal displacement of the trachea by the cranial mediastinal mass on the radiographs

12 岁雌性已绝育万能梗（Airedale terrier），

左侧位(A)和腹背位 (B)胸片

和 第四胸椎横断面增强后CT图像软组织窗(C)(窗宽290HU，窗位45HU)，

一个前纵隔肿物，手术活检后诊断为胸腺鳞状细胞癌。

在X线片上可见经前纵隔肿物引起的气管向背侧移位。

图 FIGURE 2

Right lateral (A) and ventrodorsal (B) thoracic radiographs and transverse postcontrast CT image (C) in a lung window (window width 1400 HU, window level −500 HU) at the level of the eighth thoracic vertebra of an 11‐year‐old male castrated West Highland White Terrier with a left caudal lung lobe mass diagnosed as a pulmonary adenocarcinoma on surgical biopsy. Note the lateral and caudal location of the mass on the radiographs

11岁雄性已绝育西部高地白梗，

右侧位(A)和腹背位 (B)胸片

和 第八胸椎横断面增强后CT图像肺窗(C)(窗宽1400HU，窗位-500HU)，

手术活检左后肺叶肿物诊断为肺腺癌。

注意X线片上肿物的靠外侧和靠后侧的位置。

图 FIGURE 3

Challenging cases: Left lateral (A) and ventrodorsal (B) thoracic radiographs and transverse postcontrast CT image (C) in a lung window (window width 1400 HU, window level −500 HU) at the level of the second intercostal space of 12‐year‐old female spayed Cocker Spaniel with a left cranial lung lobe mass diagnosed as a pulmonary papillary adenocarcinoma on surgical biopsy. While this case was correctly classified on CT evaluation, none of the three reviewers correctly classified this mass as pulmonary in origin on the radiographic review. This case is one of the few examples of pulmonary masses that did not follow the pattern of being located lateral to midline and in the caudal thorax. Images (D‐F) represent a case in which there was a lack of consensus between reviewers; right lateral (D) and ventrodorsal radiographs (E) and a transverse postcontrast CT image (F) in a soft tissue window (window width 290 HU, window level 45 HU) at the level of the third intercostal space of a 6‐year‐old male child castrated Norfolk Terrier with a left cranial lung lobe torsion. Only two of the three reviewers correctly classified this lesion as pulmonary. While this lesion was located lateral to midline, the cranial location was misleadingly suggestive of a mediastinal origin

具有挑战性的病例:

12 岁雌性已绝育可卡犬，左前肺叶肿物，

左侧位(A)和腹背位(B)胸片

和第二肋间隙水平横断面增强后CT图像(C)肺窗(窗宽1400HU，窗位-500HU)，

手术活检诊断为肺乳头状腺癌。

虽然这个病例在CT上被正确地分类，

但是三位阅片员在影像学检查中都没有正确地将这个肿块归为肺源性肿块。

这个病例是少数肺部肿物不遵循中线外侧和后侧胸腔的模式的例子之一。

图片(D‐F)代表了阅片员之间缺乏共识的案例，

6岁雄性（幼年绝育）诺福克梗犬。

右侧位(D)、腹背位X线片(E)

和第三肋间隙横断面增强后CT图像(F)软组织窗(窗宽290 HU，窗位45 HU)，

左侧前肺扭转。

三位阅片员中只有两位正确地将这种病变归类为肺部病变。

虽然病灶位于中线的外侧，但其前侧位置会误导人认为其起源于纵隔。

图 FIGURE 4

Misclassified case: Left lateral (A) and ventrodorsal (B) radiographs and a transverse postcontrast CT image (C) in a soft tissue window (window width 290 HU, window level 45 HU) at the level of the eight intercostal space of a 14‐year‐old female spayed Jack Russell Terrier with a surgically confirmed pulmonary papillary adenocarcinoma. This case was incorrectly classified as mediastinal on the CT evaluation based on reviewer consensus predominately due to subjective midline location and displacement of mediastinal structures. Additionally, based on the radiographic review this case represents another case in which there was a lack of consensus between reviewers, while the primary bronchus of the right caudal lung lobe is abruptly tapered adjacent to the mass on the radiographs, the mass is located close to midline, which were confounding characteristics. Only two of the three reviewers correctly classified this mass as pulmonary in origin on the radiographic review

分类错误的病例:

14岁雌性已绝育杰克罗素梗犬，

左侧位(A)和腹背位 (B)X 线片和第八肋间隙横断面增强后CT图像(C)软组织窗口(窗宽290HU，窗位45HU)，手术证实肺乳头状腺癌。

该病例在CT评估中，主要是由于主观的纵隔中线位置和纵隔结构移位，

根据阅片员的共识，被错误地归类为纵隔。

此外，基于这个病例的X线检查代表了阅片者之间缺乏共识的又一个例子,

而右后肺叶的主支气管由于X线片上的邻近肿物而突然变细，肿物靠近中线，具有多样特征。

三位阅片员中只有两位在放射线检查中正确地将此肿块归类为肺源性肿块。