Radiographic Diagnosis of Pleural Effusion and Pulmonary Edema in Dogs and Cats
犬貓胸腔積水和肺水腫的 X 光診斷

Pleural effusion and pulmonary edema both cause increased soft tissue opacity of the thoracic cavity; however, the disease processes are within different compartments or spaces.
胸腔積水、肺水腫均造成胸腔軟組織透光度增加；然而，疾病過程發生在不同的區域或空間內。
An interpretation paradigm that can be used to review the thoracic structures includes extrathoracic structures, pleural space, pulmonary parenchyma, and the mediastinum (including the cardiac silhouette).
可用於檢查胸腔結構的解釋範例包括胸腔外結構、胸膜腔、肺實質和縱膈（包括心影）。
Abnormally increased soft tissue opacity can border efface with the normal soft tissue opaque structures of the thorax from any of these compartments; however, the focus of this article is recognizing pleural disease (effusion specifically) and pulmonary edema.
異常增加的軟組織不透明度可與胸部任何區域正常的軟組織不透明結構邊界消失；然而，本文的重點是識別胸膜疾病（特別是積液）和肺水腫。
Some disease processes will cause an increased soft tissue opacity within both the pleural space and the pulmonary parenchyma (e.g., dilated cardiomyopathy, left- and right-sided heart failure).
有些疾病過程會導致胸膜腔和肺實質內的軟組織不透明度增加（例如擴張型心肌病變、左側和右側心臟衰竭）。
Depending on the assessment and the differential diagnoses (prioritized according to signalment, presenting signs, and clinical physical findings), the specific differentials for pleural effusion and pulmonary parenchymal changes could be the same or totally different.
根據評估和鑑別診斷（根據訊號、表現體徵和臨床體徵進行優先排序），胸腔積液和肺實質變化的具體鑑別可能相同或完全不同。
The radiographic evaluation will lead to appropriate next steps for further evaluation, which could include sampling of fluid or pulmonary parenchyma or further evaluation of the thorax by using additional imaging modalities (e.g., ultrasonography, computed tomography).
放射線評估將引導採取適當的後續步驟進行進一步評估，其中可能包括採集液體或肺實質樣本或透過使用其他影像方式（例如超音波檢查、電腦斷層掃描）對胸腔進行進一步評估。

Normal Anatomy  正常解剖學

In the healthy dog, a scant volume of pleural fluid separates the visceral and parietal pleural margins, but this volume is so small that there is no separation between these margins that can be visualized on thoracic radiographs.
在健康的狗中，少量的胸膜液將髒層胸膜邊緣和壁層胸膜邊緣分隔開，但這種量非常少，以至於這些邊緣之間沒有可以在胸部 X 光片上看到的分隔。
The interlobar fissures are found in expected anatomic locations that can be associated with the intercostal spaces as found on lateral and ventrodorsal/dorsoventral (VD/DV) radiographs (FIGURE 1).
葉間裂位於預期的解剖位置，可能與側位和腹背/背腹 (VD/DV) X 光片上的肋間隙相關（圖 1）。

Figure 1. Ventrodorsal radiograph of a normal dog; white lines indicate areas where a pleural fissure line would occur when an effusion is present.
圖 1.正常犬的腹背 X 光片；白線表示積液存在時會出現胸膜裂線的區域。

The pleural space exists between each lung lobe at the interlobar fissure as well as around the lung lobes themselves. The pleural space reflects back on itself at the mediastinum.^1,2 These fissures are not seen on normal thoracic radiographs unless directly tangential to the x-ray beam. The most common pleural fissure noted is the one between the right middle and right caudal lung lobes on a left lateral radiograph (FIGURE 2).
胸膜腔位於肺葉間裂處的每個肺葉之間以及肺葉周圍。胸膜腔在縱膈處反射回自身。 ^1,2 除非這些裂縫直接與 X 射線束相切，否則在正常的胸部 X 光片上是看不到的。最常見的胸膜裂是左側位 X 光片上右中肺葉和右尾肺葉之間的胸膜裂（圖 2）。

Figure 2. Left lateral radiograph with a pleural fissure line indicated (white arrow). This fissure line is a common finding on left lateral radiographs in dogs. Note that it is a relatively consistent thickness throughout and the fissure does not widen toward the periphery.
圖 2. 左側位 X 光片顯示胸膜裂線（白色箭頭）。這種裂縫線在狗的左側 X 光片上很常見。請注意，其整體厚度相對一致，且裂縫不會向周邊變寬。
The cardiac silhouette and diaphragm can be easily visualized, indicating that a pleural effusion is not present.
心影和橫膈膜清晰可見，表示沒有胸腔積水。

Occasionally, fat deposits within a fissure will separate the 2 lung lobes, most commonly between the right cranial and right middle lung lobes, as seen on a VD/DV radiograph (FIGURE 3). The pleural fissures are in classic anatomic positions, and one should be familiar with these positions as well as the basic anatomic shape of the lung lobes themselves.
有時，裂隙內的脂肪沉積會將兩個肺葉分開，最常見的是右顱葉和右中肺葉之間，如 VD/DV 射線照片所示（圖 3）。胸膜裂處於經典的解剖位置，應該熟悉這些位置以及肺葉本身的基本解剖形狀。

Figure 3. Fat is noted on this ventrodorsal radiograph of a small-breed dog between the right cranial and right middle lung lobes (white arrows). Note that the fat within the fissure is thickest centrally and thinnest peripherally.
圖 3. 在小型犬的腹背 X 光片上可以看到位於右側顱骨和右中肺葉之間的脂肪（白色箭頭）。請注意，裂縫內的脂肪在中心最厚，在外圍最薄。
This appearance is the opposite of that of pleural effusion, in which the widest portion of the pleural fluid is peripheral and thins as it extends medially in the pleural fissure line.
這種表現與胸腔積液的表現相反，胸腔積液最寬的部分是外周，並且在胸膜裂線向內側延伸時變薄。

Each lung lobe has a distinct anatomic location. On each lateral radiograph, a dorsal fissure is located around T6 between the cranial and caudal lung lobes. Attempt to identify each lobar bronchus on each radiographic view. On lateral views, the ventrally oriented lobe bronchi may be difficult to visualize (especially the right middle bronchus on a right lateral radiograph).
每個肺葉都有獨特的解剖位置。在每個側位片上，背裂位於顱側肺葉和尾側肺葉之間的 T6 周圍。嘗試在每張射線視圖上識別每個葉支氣管。從側面看，腹側葉支氣管可能難以看見（尤其是右側位 X 光片上的右中支氣管）。
The right cranial lung lobe bronchus exits the carina dorsal to the heart base and turns 90° in a ventral and cranial direction (FIGURE 4). The left cranial lung lobe bronchus exits the ventral trachea at the carina (FIGURE 4). Within approximately a centimeter from its origin, the left cranial lobar bronchus divides into the cranial and caudal segmental bronchi. Just caudal and ventral to the carina, the right middle lung lobar bronchus originates from the ventral and lateral aspect of the right caudal lobe bronchus.
右顱肺葉支氣管從心底背側的隆突出來，向腹側和顱側旋轉 90°（圖 4）。左顱肺葉支氣管在隆突處從腹側氣管出來（圖 4）。左側顱葉支氣管距其起源約一公分內分為顱段支氣管和尾段支氣管。右中肺葉支氣管位於隆突的尾部和腹側，起源於右尾葉支氣管的腹側和外側。
The accessory lung lobar bronchus originates from the right caudal lobe bronchus, 2 to 3 cm caudal to the carina in a ventromedial position.
副肺葉支氣管起源於右尾葉支氣管，位於隆突尾部 2 至 3 公分處的腹內側位置。

Figure 4. Right lateral radiograph of a normal dog in which the origin of the right cranial lobe bronchus is noted as a radiolucent circle in the cranial aspect of the carina (white arrow). The opening of the left cranial lobe bronchus points straight down (asterisk) from the floor of the carina and then bifurcates into the cranial and caudal subsegments.
圖 4. 正常狗的右側位 X 光片，其中右側顱葉支氣管的起源在隆突顱側有一個透射線圓圈（白色箭頭）。左顱葉支氣管的開口從隆突底部垂直向下（星號），然後分為顱側和尾側亞段。

Technical Radiographic Considerations
射線照相技術考量

In veterinary medicine, the standard of care has become a minimum of 3 radiographic views of the thorax. There is a “blind spot” ventrally and centrally along the cardiac silhouette on the VD/DV images where pulmonary lesions may not be seen.
在獸醫學中，護理標準已成為至少 3 次胸部放射檢查。在 VD/DV 影像上，心臟輪廓的腹側中央有一個“盲點”，在該處可能看不到肺部病變。
Recumbent lesions (lesions in the down lung when the patient is in lateral recumbency) will border efface with the surrounding pulmonary parenchyma from atelectasis. These lesions can be up to 5 cm and still not be seen on the image.
臥位病灶（患者處於側臥時，病灶位於下肺）將與因肺不張而導致的周邊肺實質邊界消失。這些病變可達到 5 厘米，但在圖像上仍無法看到。
For emergency cases, a dorsoventral thoracic radiograph can be performed initially but should be followed up with a complete set of thoracic radiographs (right lateral, left lateral, and VD/DV) after the patient has been stabilized.
對於緊急情況，可以先進行背腹側胸部 X 光檢查，但應在患者情況穩定後進行全套胸部 X 光檢查（右側面、左側面和 VD/DV）。

The thoracic radiographs should be taken during peak inspiration and should be centered over the cardiac silhouette so that the thoracic inlet and the caudodorsal portion of the caudal lung lobes appear on the same radiograph.
胸部 X 光片應在吸氣高峰時拍攝，並應位於心影的中心，以便胸腔入口和尾部肺葉的尾背部分出現在同一 X 光片上。
Doing so may not be possible with a 14” × 17” or a 17” × 17” DR/CR (digital radiography/computed radiography) plate on a large breed dog (e.g., Great Dane), for which 2 images would be required for each view (cranial thorax and caudal thorax), ensuring that there is overlap in the middle.
對於大型犬（例如大丹犬），使用 14” × 17” 或 17” × 17” DR/CR（數位射線照相/電腦射線照相）板可能無法做到這一點，因為每個視圖（前胸部和尾胸）都需要 2 張影像，以確保中間有重疊。
The technique typically involves high kVP and low mA; the highest mA and fastest time setting(s) used to obtain mAs are in the 1 to 5 range. For a small dog or cat, the kVP may still be in the 60 to 70 range.
該技術通常涉及高 kVP 和低 mA；用於獲得 mAs 的最高 mA 和最快時間設定在 1 至 5 範圍內。對於小型犬或貓來說，kVP 可能仍在 60 到 70 範圍內。

Straight positioning is essential for accurate interpretation. The VD/DV images should be straight. On lateral views, the sternum should align with the thoracic vertebrae, and each left and right rib head should be superimposed over the other.
直線定位對於準確的解釋至關重要。 VD/DV 影像應該是直的。從側面看，胸骨應與胸椎對齊，並且左右肋骨頭應相互重疊。
Sometimes for lateral radiographic views, a triangular sponge positioning device is required to lift the sternum away from the table to get the sternum and spine at a similar height before taking the radiograph.
有時對於側位射線照相視圖，需要使用三角形海綿定位裝置將胸骨抬離桌子，以使胸骨和脊椎處於相似的高度，然後再進行射線照相。
Peak inspiration means that the cupola of the diaphragm is drawn caudal to the cardiac silhouette and the caudodorsal lung margins reach to the level of T12 to T13 in dogs and T13 to L1 in cats. An expiratory radiograph will negatively affect interpretation in 2 primary ways.
峰值吸氣意味著膈肌穹窿被拉向心影的尾部，並且尾背肺邊緣達到狗的 T12 至 T13 水平或貓的 T13 至 L1 水平。呼氣 X 光片主要會透過兩種方式對解釋產生負面影響。
First, the cardiac silhouette will always look big relative to the overall thoracic volume; and second, the lungs will look whiter (more opaque) than is typical because the decreased pulmonary volume results in less gas between the pulmonary vascular structures.
首先，相對於整個胸腔體積而言，心臟輪廓總是看起來很大；其次，由於肺部容量減少導致肺血管結構之間的氣體減少，肺部看起來會比正常情況下更白（更不透明）。
For a small dog being evaluated for a cough, if only a right lateral radiograph is taken on expiration, it is likely that the cardiac silhouette will appear enlarged and opacity of the pulmonary parenchyma increased, which could be mistaken for pulmonary edema.
對於正在評估咳嗽的小型犬，如果在呼氣時只拍攝右側 X 光片，則心臟輪廓可能會擴大並且肺實質的不透明度增加，這可能會被誤認為是肺水腫。
If you were to repeat the radiograph on inspiration and take the dorsoventral or ventrodorsal views, you may realize that the thorax could be normal.
如果您在吸氣時重複拍攝射線照片並進行背腹側或腹背側視圖，您可能會發現胸腔可能是正常的。

Pleural Effusion  胸腔積水

If you believe that the pleural space is abnormal, ask the following questions: Is there pleural fluid or pleural air? Are there any extrapleural signs or masses? Are the ribs and osseous structures of the thorax normal? Are there any diaphragmatic abnormalities such that a diaphragmatic rupture should be considered?
如果您認為胸膜腔異常，請詢問以下問題：是否有胸膜積水或胸膜空氣？有胸膜外體徵或腫塊嗎？胸部的肋骨和骨性結構是否正常？是否有任何橫膈肌異常，需要考慮橫膈膜破裂嗎？
If the answer to any of these questions is yes, then details regarding the abnormality should be described. See BOX 1 for radiographic interpretations of pulmonary lesions. For example, a large, expansile mass associated with the right 7th rib causes focal medial retraction of the pleural space and lung margins with a moderate volume of focal pleural effusion.
如果對其中任何一個問題的答案是肯定的，那麼就應該描述有關異常的詳細資訊。有關肺部病變的放射學解釋，請參閱框 1。例如，與右側第 7 肋相關的大的、膨脹性的腫塊導致胸膜腔和肺邊緣的局部內側回縮，並伴有中等量的局部胸腔積液。
An extrapleural sign is an area of increased soft tissue opacity that appears to be within the lung field and is being caused by indentation from an extrapleural structure. The structure could be normal (e.g., costochondral junction of a chondrodystrophic dog, such as a basset hound) or a primary abnormality (e.g., rib fracture, rib tumor).
胸膜外徵是指肺部區域內軟組織不透明度增加的區域，是由胸膜外結構的壓痕引起的。此結構可能是正常的（例如，軟骨營養不良症犬（如巴吉度獵犬）的肋軟骨連接處）或原發性異常（例如，肋骨骨折、肋骨腫瘤）。

Common causes of pleural effusion (transudate, modified transudate, or exudate) are listed in BOX 2.^2,3
胸腔積液（漏出液、改良漏出液或​​滲出液）的常見原因列於框 2 中。

The radiographic diagnosis of pleural effusion (FIGURES 5–7) is based on the radiographic abnormalities listed in BOX 3.
胸腔積水的 X 光診斷（圖 5-7）是基於框 3 中列出的 X 光異常。

Figure 5. A right lateral radiograph of a dog with a mild pleural effusion that is collecting ventrally. There is mild dorsal elevation of the pulmonary lobes ventrally with widening of the ventral pleural fissures in the caudoventral thorax over the region of the apex of the cardiac silhouette.
圖 5. 狗的右側 X 光片，顯示少量胸腔積液，積液向腹部聚集。肺葉向腹側輕度抬高，心影頂點區域的尾腹側胸膜裂隙增寬。

Figure 6. A right lateral radiograph of a dog with a chylothorax creating a moderate pleural effusion. There are similar features as in FIGURE 5 as well as border effacement of the cardiac silhouette and rounding of the caudodorsal lung lobes. The metallic staples are from a procedure for occlusion of the thoracic ducts.
圖 6. 患有乳糜胸並產生中度胸腔積液的狗的右側位 X 光片。具有與圖 5 相似的特徵，以及心影邊界消失和尾背肺葉變圓。這些金屬釘是來自胸導管阻塞手術。

Figure 7. Right lateral radiograph of a dog with a severe pleural effusion secondary to hypoproteinemia. There is border effacement of the cardiac silhouette and diaphragm along with the other features of pleural effusion described in the article text and shown on FIGURES 5 and 6.
圖 7. 因低蛋白血症而出現嚴重胸腔積水的狗的右側 X 光片。心影和橫膈膜邊界模糊，並有文章正文中描述的其他胸腔積液特徵，如圖 5 和圖 6 所示。
Three central catheters are noted: central venous line (bottom left), nasogastric feeding tube (middle), and pleural chest tube (top right).
值得注意的是三個中心導管：中心靜脈導管（左下）、鼻胃管（中）和胸膜胸管（右上）。

In patients with effusion, soft tissue opacity or fluid accumulation will be present within the interlobar fissures, which will be widest peripherally and thinner centrally. The costophrenic and lumbar diaphragmatic angles will be rounded or blunted as a result of fluid accumulation in these regions.
積液患者的葉間裂隙內會出現軟組織不透明或積液，葉間裂隙週邊最寬，中心較薄。由於這些區域中的液體積聚，肋膈角和腰膈角將變圓或變鈍。
There will be partial or complete border effacement of the cardiac silhouette and diaphragm (FIGURE 6). In patients with severe pleural effusion, the trachea may be dorsally elevated (FIGURE 7).
心影和膈肌的邊界將會部分或完全消失（圖 6）。對於嚴重胸腔積水的患者，氣管可能會向背側隆起（圖 7）。

Unilateral pleural effusions are usually secondary to exudates because the mediastinum in dogs and cats is considered fenestrated. A transudate or a modified transudate should pass freely between the right and left pleural space through the mediastinal fenestrations.
單側胸腔積水通常是由於滲出液引起的，因為狗和貓的縱隔被認為是有孔的。漏出液或改良的漏出液應透過縱膈孔在左右胸膜腔之間自由通過。
With an exudative effusion, these fenestrations will become plugged, resulting in a unilateral pleural effusion (e.g., chylothorax, pyothorax, hemothorax, neoplastic effusion). In a reactive exudative effusion, such as one secondary to chylothorax, the visceral pleural surface will be thickened and the lung lobe margins rounded.
當發生滲出性胸腔積水時，這些孔洞會被阻塞，導致單側胸腔積水（例如乳糜胸、膿胸、血胸、腫瘤性積液）。在反應性滲出性胸腔積液中，例如繼發於乳糜胸的胸腔積液，臟層胸膜表面會變厚，肺葉邊緣會變圓。
This restrictive pleuritis results in the inability of the lung lobes to reinflate to their normal shape or volume (FIGURE 8).
限制性胸膜炎導致肺葉無法重新恢復正常形狀或體積（圖 8）。

Figure 8A. Right lateral (A) and ventrodorsal (B) radiographs of a cat with severe chronic chylothorax and pneumothorax
圖 8A。患有嚴重慢性乳糜胸和氣胸的貓的右側面 (A) 和腹背 (B) X 光片

Figure 8B. Right lateral (A) and ventrodorsal (B) radiographs of a cat with severe chronic chylothorax and pneumothorax. There is marked thickening of the visceral pleura and rounding of the lung lobe borders. There are multiple chronic rib fractures with callus formation consistent with a “thoracic bellows effect” from the chronic chylothorax.
圖 8B。患有嚴重慢性乳糜胸和氣胸的貓的右側面 (A) 和腹背 (B) X 光片。臟層胸膜明顯增厚，肺葉邊界圓。有多處慢性肋骨骨折，並有骨痂形成，與慢性乳糜胸的「胸廓風箱效應」相符。
Subcutaneous emphysema is noted on the left side of the thorax consistent with recent thoracentesis. There is also dorsal bowing of the caudal sternum (pectus excavatum).
胸部左側出現皮下氣腫，與最近的胸腔穿刺結果一致。尾部胸骨也向背側彎曲（漏斗胸）。

The differential diagnoses for chronic bilateral pleural effusion that should be ruled out include chronic diaphragmatic hernia, thoracic malignancy (commonly a rib tumor), and lung lobe torsion (may cause the effusion or be secondary to a chronic effusion).
應排除的慢性雙側胸腔積水的鑑別診斷包括慢性膈疝，胸部惡性腫瘤（常見為肋骨腫瘤）和肺葉扭轉（可能導致積液或繼發於慢性積液）。

Pulmonary Edema  肺水腫

Pulmonary edema is the abnormal accumulation of fluid within the interstitial space of the lungs, based on abnormalities of Starling’s forces across the capillary bed and interstitium.⁴ Common causes of pulmonary edema are listed in BOX 4. Net flow of fluid into the pulmonary interstitial space can result from alterations in plasma albumin (plasma oncotic pressure), elevated venous hydrostatic pressure (elevated left atrial pressures), increased capillary permeability (membrane breakdown), and increased osmotic (oncotic) pressures within the interstitial space.
肺水腫是由於毛細血管床和間質中 Starling 力異常而導致肺間質內液體積聚異常。 ⁴ 框 4 列出了肺水腫的常見原因。

Radiographic signs of pulmonary edema can be found in BOX 5.
肺水腫的 X 光影像可在框 5 中找到。

In patients with cardiogenic pulmonary edema, elevated venous hydrostatic pressure will lead to retention of interstitial fluid (unstructured interstitial pulmonary pattern).
在患有心源性肺水腫的患者中，靜脈靜水壓升高會導致間質液滯留（非結構性間質肺模式）。
In dogs, cardiogenic pulmonary edema is secondary to left-sided cardiac failure; therefore, radiographs will usually show left-sided cardiomegaly, elevation of the carina and caudal thoracic trachea, and a caudodorsal distribution of the increased pulmonary opacity (most commonly unstructured interstitial) that starts from a central or hilar location and spreads peripherally (FIGURE 9).
在狗中，心因性肺水腫是繼發於左側心臟衰竭的；因此，X 光通常會顯示左側心臟擴大、隆突和尾部胸氣管升高，以及增加的肺部不透明度（最常見的是非結構化間質）在尾部背側分佈，從中央或肺門位置開始並向周圍擴散（圖 9）。

Figure 9A. Right lateral (A) and ventrodorsal (B) radiographs of a Doberman pinscher with congestive heart failure secondary to dilated cardiomyopathy.
圖 9A。杜賓犬因擴張型心肌病變而出現充血性心臟衰竭的右側面 (A) 和腹背面 (B) X 光片。

Figure 9B. Right lateral (A) and ventrodorsal (B) radiographs of a Doberman pinscher with congestive heart failure secondary to dilated cardiomyopathy. There is a pleural effusion (mild in severity) noted secondary to right-sided heart failure as evidenced by multiple pleural fissure lines and mild retraction of the lung lobes away from the thoracic walls (arrows).
圖 9B。杜賓犬因擴張型心肌病變而出現充血性心臟衰竭的右側面 (A) 和腹背面 (B) X 光片。因右側心臟衰竭而出現胸腔積水（嚴重程度較輕），表現為多條胸膜裂隙線和肺葉輕度回縮遠離胸壁（箭頭）。
There is cardiomegaly and pulmonary venous enlargement. There is an unstructured interstitial pulmonary pattern noted, consistent with cardiogenic pulmonary edema.
有心臟擴大和肺靜脈擴張。注意到非結構化的間質性肺模式，與心源性肺水腫一致。

This caudodorsal distribution of the pulmonary changes is seen in dogs with mitral valve disease/insufficiency but not necessarily in dogs with left-sided cardiac failure secondary to cardiomyopathy, which could be more randomly distributed.
患有二尖瓣疾病/功能不全的狗會出現這種向尾背側分佈的肺部變化，但患有繼發於心肌病變的左側心臟衰竭的狗則不一定會出現這種變化，後者的分佈可能更加隨機。
In some dogs with mitral valve degenerative disease, the pulmonary edema will be distributed in the right caudal lobe due to the relative relationship between the right caudal lobe pulmonary vein and the direction of the regurgitant jet from the left ventricle into the left atrium (FIGURE 10). An unstructured interstitial pulmonary pattern can progress to an alveolar pulmonary pattern (part of a continuum of the same disease process, exhibiting different patterns depending on the severity of the disease). In dogs with dilated cardiomyopathy, congestive right- and left-sided heart failure can result in pleural effusion and pulmonary edema, respectively.
在一些患有二尖瓣退化性疾病的狗中，由於右尾葉肺靜脈與從左心室進入左心房的逆流噴射方向之間的相對關係，肺水腫將分佈在右尾葉（圖 10）。非結構化的間質肺模式可發展為肺泡肺模式（同一疾病過程的連續部分，根據疾病的嚴重程度表現出不同的模式）。對於患有擴張型心肌病變的狗來說，充血性右側和左側心臟衰竭分別可導致胸腔積水和肺水腫。

Figure 10A. (A) Right lateral and (B) ventrodorsal (VD) radiographs of a dog with chronic mitral valve degenerative disease.
圖 10A。患有慢性二尖瓣退化性疾病的狗的 (A) 右側面和 (B) 腹背 (VD) 射線照片。

Figure 10B. (A) Right lateral and (B) ventrodorsal (VD) radiographs of a dog with chronic mitral valve degenerative disease. There is moderate to severe left-sided cardiomegaly with left atrial enlargement and dorsal elevation of the trachea and carina.
圖 10B。患有慢性二尖瓣退化性疾病的狗的 (A) 右側面和 (B) 腹背 (VD) 射線照片。左側心臟有中度至重度擴大，左心房擴大，氣管及隆突背側抬高。
There is an increased unstructured interstitial pulmonary pattern within the right caudal lung lobe, best visualized on the VD radiograph, consistent with cardiogenic pulmonary edema (arrow).
右尾肺葉內非結構性間質性肺圖案增加，在 VD 射線照片上看得最清楚，與心因性肺水腫（箭頭）一致。

Cardiogenic pulmonary edema in cats will be distributed more randomly than just caudodorsally (FIGURE 11); it can be distributed ventrally and multifocally. Cats with primary or secondary myocardial disease can exhibit left-sided heart failure (causing pulmonary edema and pleural effusion), right-sided heart failure (causing pleural and peritoneal effusion), or both.
貓的心因性肺水腫分佈不僅沿尾背部，而且更為隨機（圖 11）；可呈腹側分佈、多灶性分佈。患有原發性或繼發性心肌疾病的貓可能出現左側心臟衰竭（引起肺水腫和胸腔積液）、右側心臟衰竭（引起胸腔和腹腔積液）或兩者兼有。

Figure 11A. Right lateral (A) and ventrodorsal (B) radiographs of a cat with cardiogenic pulmonary edema.
圖 11A。患有心因性肺水腫的貓的右側面 (A) 和腹背面 (B) X 光片。

Figure 11B. Right lateral (A) and ventrodorsal (B) radiographs of a cat with cardiogenic pulmonary edema. The cardiac silhouette is severely enlarged and there is a randomly distributed mixed pulmonary pattern consisting of an unstructured interstitial to alveolar pulmonary patterns.
圖 11B。患有心因性肺水腫的貓的右側面 (A) 和腹背面 (B) X 光片。心影嚴重擴大，並有隨機分佈的混合肺部圖案，由非結構化的間質到肺泡肺部圖案組成。
The pulmonary vessels are enlarged centrally but not in the peripheral aspect of the lung field.
肺血管在中央擴張，但在肺野的周圍沒有擴張。

Summary  概括

Pulmonary edema should not be confused with pleural effusion. Although congestive right- and left-sided heart failure can result in both, usually the disease processes that will cause pulmonary edema versus pleural effusion differ.
肺水腫不應與胸腔積水混淆。儘管充血性右側和左側心臟衰竭可導致兩者，但通常導致肺水腫和胸腔積水的疾病過程不同。
Recognizing pleural effusion is based on seeing radiographic pleural fissure lines with retraction of the visceral pleural surface away from the parietal surface. Recognizing pulmonary edema as a pulmonary pattern is also critical for identifying parenchymal lesions versus pleural space abnormalities. Radiography is an essential part of classifying thoracic disease processes.
識別胸腔積液是基於看到 X 光胸膜裂隙線以及臟層胸膜表面從壁層表面回縮。認識到肺水腫是一種肺部疾病類型對於識別實質病變與胸膜腔異常也至關重要。放射線照相術是分類胸部疾病過程的重要部分。
Diagnosis can be facilitated by dividing the thorax into the 4 radiographic compartments (extrathoracic structures, pleural space, pulmonary parenchyma, and the mediastinum) and combining those findings with signalment, presenting complaint, and physical examination results.
可以透過將胸腔分為 4 個放射區（胸腔外結構、胸膜腔、肺實質和縱隔），並將這些發現與訊號、主訴和身體檢查結果相結合來促進診斷。