Dr. Cáceres is taking a well-earned holiday with his new bodyguard but he does not forget you! He has recorded his last webinar and we are publishing it today! Enjoy it and learn a few tips about lobar collapse :D. Will see you again on September.
presenting chest radiograph of a 77-year-old man with malaise and weight loss.
What do you see?
This is the last case before the summer. Will see you again in September. Enjoy your vacation!
Click here to see the solution
Findings: PA radiograph shows increased opacity of the left hilum (A, arrow), which is due to a mass projected over it, as seen in the lateral view (B, arrows). In addition, there is convexity of the aortopulmonary window (A, red arrow)
The increased hilar opacity (C, arrow) was not visible in a PA radiograph taken six months earlier (D, circle). Convexity of the aortopulmonary window (C, red arrow) was not present at that time.
In the lateral view, the mass (E, arrows) was visible six month earlier, albeit smaller (F, arrow). This progression indicates rapid growth.
Enhanced axial and coronal CT confirms a pulmonary mass invading the aortopulmonary window (G and H, arrows). Lung metastases were present (insert, red arrows)
Diagnosis: lung carcinoma invading the aortopulmonary window
I am presenting this case to discuss the aortopulmonary window (APW), which is a small mediastinal space located between the aortic knob and the pulmonary artery in the PA view (Fig 1A). The APW is normally concave; convexity (Fig 1B) suggests an abnormality that should be studied with enhanced CT.
Visibility of the APW is difficult in the elderly, because the superimposed uncoiled descending aorta makes the interpretation more difficult (Fig 2).
Convexity of the APW may be overlooked unless we look specifically at the area (fig 3). The larger the abnormality, the more readily it is detected in the chest radiograph. Subtle changes are more difficult to identify and comparing with previous films is very helpful.
Causes that may alter the APW are: tumors, enlarged lymph nodes, aortic aneurysms and increased mediastinal fat. The phrenic nerve crosses this space and a phrenic neurinoma may also grow in the APW, although I have never seen a case.
Enlarged lymph nodes are by far the most common cause of occupation of the APW. They may occur in malignant and non-malignant diseases. They usually coexist with radiographic manifestations of the primary process (Figs 4 and 5).
In isolated occupation of the APW the etiology cannot be determined in the chest radiograph and enhanced CT should be obtained (fig 6).
Aortic aneurysm is an uncommon cause of convexity of the APW (Fig 7). The abnormality is initially subtle and it becomes more evident as the aneurysm grows (Fig 8).
Radiographs taken five years earlier did not show the abnormality (E and F, circles).
Enhanced axial and coronal CT demonstrate that the mass represents a saccular aneurysm arising from the aortic arch (G and H, arrows).
Comparison with previous films shows a normal APW in 2007 and progression of the opacity over a three-year period (arrows).
Enhanced CT shows that the opacity represents a partially thrombosed aneurysm arising from the inferior aspect of the aortic arch (C-D and E, arrows).
Last but not least, we should remember that mediastinal fat is an innocuous cause of convexity of the APW (Fig 9).
Follow Dr. Pepe’s advice:
1. Convexity of the APW suggests underlying pathology.
2. Enlarged lymph nodes are the most common cause of a convex APW.
3. Aneurysm and mediastinal fat may also enlarge the APW
This case belong to the section “The wisdom of Dr. Pepe”, in which an (useful?) aphorism ends the presentation.
I am presenting a routine PA radiograph in an asymptomatic 79-year-old woman operated on for a breast DCIS five years ago. PA radiograph taken five years earlier is shown for comparison. More images will be shown on Wednesday.
3. Primary lung tumor(s)
4. Any of the above
showing CT images with and without contrast enhancement.
What would your diagnosis be?
2. Active TB
3. Fibrous lung tumor
4. Any of the above
Click here to see the answer
Findings: The PA chest radiograph shows two obvious small nodules in the left middle lung field (A, circle), not present five years earlier (B). In my experience, two nodules close together are usually granulomas. But in this case we have another finding: a subtle bulge in the left hilum (A, arrow), not visible in the previous film, highly suspicious of hilar adenopathy. This changes the diagnostic orientation and makes us think of an active process.
Unenhanced axial CT shows an hourglass-shaped pulmonary lesion (C and D, arrows) that simulated two nodules in the chest radiograph. The lesion enhances after contrast injection and contains a large arterial vessel (E, arrow). Non-enhancing lymph nodes are visible in the left hilum (F, arrow).
Although all three diagnoses offered in the blog can cause hilar adenopathy, the vascularity of the lesion points to a tumor.
PET-CT shows faint uptake of the primary lesion and the hilar lymph nodes (G and H, arrows). A needle biopsy (I, arrow) came back as an atypical small-cell tumor.
The patient was treated with chemotherapy and radiotherapy, with a good response of the primary tumor (J, arrow) and lymph nodes (K, circle).
Final diagnosis: SCLC with hilar metastasis and a good response to QT and RT
Discussion: I just finished reading “The subtle art of not giving a f*ck“ and there is an enlightening (and sadly true) chapter entitled “You are not special”. In this particular case I was feeling special, as I diagnosed a malignant pulmonary fibroma based on a single case seen 20 years ago (see below) because of the similarity of the vascular pattern in the two cases. After 50 years of practice, I forgot a basic principle: common conditions are, well, common. I’m showing this case to remind you that when faced with a diagnostic dilemma you should first consider common options rather than uncommon ones.
To redeem myself, I am showing my only case of fibrous tumor of lung in a 37-year-old woman with hemoptysis. The PA radiograph shows a well-defined paramediastinal nodule (A, arrow). Enhanced coronal and sagittal CT confirms the intrapulmonary location of the nodule, which has a large arterial vessel in the center with an aneurysm at the end (B and C, arrows).
Two bits of information about fibrous tumor of the lung: It is a very unusual spindle-cell tumor with the same histology as fibrous tumors of pleura, and like them, it has malignant potential. It is usually asymptomatic and is seen as a rounded or ovoid nodule of varying size. Immunohistochemistry is important for the diagnosis.
Follow Dr. Pepe’s pearls of wisdom:
Always consider that what you are seeing is a rare manifestation of a common disease rather than a common manifestation of a rare disease.
today I am presenting another “Art of interpretation” case. I like them and think they have good teaching value.
Radiographs were taken for preoperative knee surgery in a 21-year-old man.
What is the most likely diagnosis?
1. Swyer-James-McLeod syndrome
2. Congenital hypoplasia of left lung
3. LUL collapse
4. None of the above
Click here to see the answer
Findings: PA radiograph shows a hyperlucent left lung with a small elevated hilum (A, white arrow). The trachea is deviated towards the left and the left main bronchus is curved upward (A, blue arrow). There is a small peak in the left hemidiaphragm (A, red arrow). And there is a triangular-shaped paraspinal opacity (A, circle), better seen in the cone down view (B, white arrow), with two linear metallic opacities inside (B, red arrows).
The lateral view (C) is unremarkable. Although the PA findings suggest loss of volume of the LUL, there are some negative findings: no anterior displacement of the left major fissure and no opacity indicative of LUL collapse.
Analysis of the findings
There are four obvious findings:
1. Hyperlucent left lung with small left hilum
2. Tracheal deviation to the left
3. Upward curving of left main bronchus
4. Juxtaphrenic peak (*)
All these findings are indicative of LUL volume loss with compensatory overinflation of the LLL.
There are two less obvious findings, which are diagnostic:
Paramediastinal opacity with surgical staples
No signs of LUL collapse in the lateral view
The first indicates previous surgery and the second excludes LUL collapse. Taken together, these findings lead to the obvious conclusion that the patient had undergone a previous lobectomy.
(*) The juxtaphrenic peak sign was described by my late friend Kenneth Kattan as an indirect sign of LUL collapse. Semin Roentgenol 1980; 15:187-193
LOSS OF VOLUME OF LUL + SURGICAL STAPLES = LUL LOBECTOMY
In the past, the patient had embryonal carcinoma of the testicle with a metastatic nodule in the LUL (A and B, arrows). He had undergone LUL lobectomy by video-assisted thoracic surgery one year before.
Final diagnosis: LUL lobectomy for metastasis of embryonal testicular carcinoma
I’m showing this case to emphasize the importance of identifying metal sutures in the chest radiograph. Nowadays, most surgical procedures are done by video thoracoscopy which doesn’t leave any telltale signs other than surgical staples. These are difficult to see because of their small size and because high kV “burns” metal density.
Staples are visible as a faint longitudinal ring chain somewhat denser than the surrounding tissues. It’s very important to be familiar with their radiographic appearance because they offer valuable information about previous surgery.
When staples are detected, our interpretation of associated findings may change, as occurred with the case presented.
To familiarize you with the radiological appearance of surgical staples, I’m showing three more cases.
88-year-o.ld man with dementia and moderate dyspnea. Chest radiographs show a nodule in the RUL (A and B, arrows). PA view shows post-surgical changes at the left 6th and 7th ribs and a hyperlucent left lung with a small hilum. There are surgical clips in the mediastinum (A and B, red circles). These findings suggest a previous LUL lobectomy and a second primary tumor. The patient’s records disclosed a LUL lobectomy for carcinoma twenty years earlier. The second primary tumor was confirmed by needle biopsy.
The radiographic findings are typical of “old” chest surgery.
PA radiograph of a 23-year-old woman with a nondescript LUL infiltrate (A, arrow). Close-up view reveals a longitudinal ring chain of staples within the infiltrate (B, arrows), pointing to a man-made opacity secondary to video thoracic surgery.
Diagnosis: changes after endoscopic LUL bullectomy for recurrent pneumothorax.
I saw this case three weeks ago and it is still unproven. A 44-year-old woman from another country came for a routine cardiac checkup. The PA chest radiograph shows a serpiginous opacity in the LLL (A, arrow) with a ring chain of staples in the periphery, better seen in the cone down view (B, arrows). On questioning, the patient mentioned previous endoscopic surgery for a nodule in the left lung two years ago. Enhanced CT shows a solid lesion with staples in the periphery (C, arrow).
As the patient could not provide previous medical records, we were unable to ensure that the changes were attributable to scar tissue. A follow-up CT has been scheduled.
Final words: Staples are difficult to reproduce on the computer screen, and I have done my best. I assure you that they are easily visible on a 14 by 17 reading console, provided that you see and recognize them 🙂
Follow Dr. Pepe’s teaching points:
1. Surgical staples are visible as a faint longitudinal ring chain.
2. They indicate previous surgery and help to interpret the chest findings under a new light.
Today I am showing radiographs of a 47-year-old woman with chronic cough.
What do you see?
Leave your comments here and come back on Friday to see the answer.
Click here to see the answer
Findings: PA radiograph shows marked downward displacement of the right hilum (A, white arrow) and verticalization of the intermediate bronchus (A, red arrow). These findings are indicative of marked volume loss of RLL. The lateral view (B) is unremarkable.
Enhanced coronal CT confirms the descended right hilum (C, white arrow), as well as the vertical intermediate bronchus (C, red arrow). A different slice shows a small calcified triangular shadow (D, arrow), which represents a markedly collapsed RLL.
Final diagnosis: severe RLL collapse due to previous TB
In the previous webinar (Diploma case 139), I described the common signs that suggest lobar collapse. In this presentation I want to review atypical forms of lobar collapse and how to recognize them.
The main signs of lobar collapse are volume loss and increased opacity of the lobe. Atypical presentations lack these traits, and the lobe appears to have an increased volume (drowned lobe) or to have collapsed without increased opacity (aerated collapse). A third variant would be a lobe that has lost most of its volume (extreme collapse) and therefore is difficult to identify as such, as occurred in the initial case.
In extreme collapse, the affected lobe is severely decreased in size and may be overlooked, or confused with a different process (Fig. 1). The diagnosis is suggested by secondary findings, such as hilar displacement and/or increased lucency of the unaffected lobe(s) (Figs. 2 and 3).
Enhanced axial CT image depicts a horizontal sliver of tissue, corresponding to the markedly collapsed RUL, sharply outlined by the minor fissure (C and D, white arrows). Note the obstructed RUL bronchus (D, red arrow). Bronchogenic carcinoma.
Enhanced axial CT shows the markedly collapsed lobe (C, arrow). Coronal CT depicts a mass obstructing the LLL bronchus (D, arrow). Final diagnosis: carcinoma.
Coronal and sagittal CT confirm the extreme LUL collapse with bronchiectasis. The major fissure is well depicted in the coronal and sagittal reconstructions (C and D, arrows).
The finding known as drowned lobe is a variant of lobar collapse in which the lobe does not decrease in size but instead, enlarges. It occurs when a slow-growing proximal tumor permits accumulation of distal secretions and infection, causing an increase in size of the lobe (Fig. 4). Bulky tumor masses may contribute to this enlargement (Fig. 5).
Enhanced axial and coronal CT shows the enlarged RUL lobe (C and D, white arrows), secondary to central obstruction of the RUL bronchus (C and D, red arrows). Diagnosis: drowned RUL secondary to central carcinoma
Enhanced axial CT confirms the swollen LLL (C, white arrow). PET-CT shows that part of the bulk is due to a large tumor mass (D, white arrow), invading the pulmonary veins and left atrium (C and D, red arrows).
In aerated collapse the lobe loses volume, but does not increase in opacity, making the collapse less obvious. This happens because increased opacity is not related with volume loss, but rather with the amount of secretions within the lobe. If the partially collapsed lobe contains air, the lobe will appear to have normal lucency.
In aerated collapse, the diagnosis is suspected by displacement of the hilum, the fissure, or both (Figs. 6-8).
Follow Dr. Pepe’s advice:
1. Common manifestations of lobar collapse are loss of volume and increased opacity.
2. Uncommon manifestations of lobar collapse are extreme collapse, drowned lobe, and aerated collapse.
3. These uncommon manifestations are suspected based on secondary signs: hilar and/or fissure displacement and increased lucency of the unaffected lobe(s).
I am presenting today a new “Art of interpretation” case.
Radiographs belong to a 51-year-old with chest pain, dyspnea and D-dimer of 750.
1. Pulmonary infarct
3. Chronic pulmonary changes
4. None of the above
What do you see? Come back on Friday to see the answer!
Click here to see the answer
Findings: the PA radiograph shows an ill-defined opacity in the right mid-lung field (A, white arrows) which looks intrapulmonary. There is blunting of the right costophrenic angle, indicative of pleural disease (A, red arrow).
The main diagnostic findings are seen in the lateral view. There are oblique posterior pulmonary strands (“crow’s feet”) (B, white arrow) which lead our attention to a posterior vertical white line (B, red arrows), which represents calcified pleura.
A negative finding is the absence of pulmonary disease in the lateral view.
These findings are better seen in the cone down views (C and D, arrows) .
Analysis of findings:
1. Apparent pulmonary disease in the PA radiograph
2. No visible pulmonary disease in the lateral view
3. Blunting of costophrenic angle with calcified posterior pleura
4. Crow’s feet
Summing up the findings: The apparent pulmonary disease in the PA view, which was not seen in the lateral view, together with chronic pleural disease (evidenced by blunting of the costophrenic angle and calcified posterior pleura) are highly suggestive of pleural disease simulating a pulmonary infiltrate.
APPARENT PULMONARY DISEASE IN THE PA RADIOGRAPH, NOT SEEN IN THE LATERAL VIEW + CALCIFIED PLEURA IN THE LATERAL VIEW = CALCIFIED PLEURA SIMULATING PULMONARY DISEASE.
Enhanced axial CT confirms the posterior calcified pleura (A, arrow), the lack of pulmonary infiltrate, and the crow’s feet adjacent to the diseased pleura (B, red arrow).
Crow’s feet are better seen in the coronal and sagittal reconstructions (C and D, red arrows), especially the sagittal view, which is practically identical to the lateral chest radiograph.
Final diagnosis: Pleural calcification simulating pulmonary infiltrate
(My heartfelt thanks to Dr. Eva Castañer for providing the CT images)
Pleural calcifications are not uncommon. Bilateral calcifications are almost always related to asbestos exposure. Unilateral calcifications are usually due to a previous infection or hemorrhage. In any case, when located in the anterior or posterior chest wall they are seen en face in the PA radiograph and may be confused with pulmonary infiltrates, as in the present case. Seen in profile in the lateral view they appear as a calcified line, and the diagnosis is then evident.
Sometimes, the calcified pleura are overlooked. In this particular case we have a useful marker that points our attention to the diseased pleura: the radiologic sign known as crow’s feet which represents subsegmental areas of peripheral fibrosis/atelectasis fixed by the fibrotic pleura. They are likely an early stage of rounded atelectasis. (Personally, I prefer the alternative term sun rays rather than crow’s feet. As a frequent visitor to Minorca, I am more familiar with sun rays than with crows, let alone their feet).
To emphasize the deceitful appearance of pleural calcification, I am showing two more cases.
Radiographs belong to a 52-year-old asymptomatic woman. The PA radiograph shows what appears to be a poorly-defined pulmonary infiltrate in the left lung (A, arrow). The lateral view shows two calcified pleural plaques: the posterior one is depicted as a calcified line (B, white arrow), whereas the anterior one is more oblique and simulates a rounded opacity (B, red arrow).
Sagittal CT clearly shows the anterior (C, arrow) and posterior plaques (D, arrow). No pulmonary infiltrates were seen in the lung view (not shown).
Preoperative PA chest radiograph in a 57-year-old man. There are several opacities in the left hemithorax that may be pulmonary infiltrates (A, white arrows) accompanied by left diaphragmatic and pleural calcifications (A, red arrows).
In the coronal CT (B) there are no lung abnormalities. Enhanced axial and sagittal CTs depict extensive pleural calcification (C and D, arrows). The apparent pulmonary infiltrates were due to pleural calcifications depicted en face. The patient had a history of TB in his youth.
Dr. Pepe’s teaching points:
1. Pleural disease can simulate pulmonary infiltrates.
2. Crow’s feet can direct our attention to overlooked pleural disease
Presenting PA chest radiograph of a 57-year-old woman with dyspnea and fever.
What would be your diagnosis?
1. Lobar collapse
3. Unilateral pulmonary edema
4. Any of the above
You have one week to post your answers. The correct answer will be given during the webinar of Wednesday 3 at 12:30 P.M.
You can join the webinar here