Cáceres Corner Case 235 – Vignette

Dear Friends,

Recommendations for this week: two series, Goliath and Fleabag both of them in Amazon. 

Today’s radiographs belong to a 32-year-old man with persistent cough. Non-smoker.


1. Bronchogenic carcinoma
2. Benign endobronchial tumor
3. Endobronchial TB
4. Any of the above

Click here to see the answer

Findings: PA shows a triangular opacity in the right upper lung (A, arrow), suggestive of RUL collapse. The collapsed lobe abuts against the major fissure in the lateral view (B, arrow).
The findings point to an obstructive lesion at the origin of the RUL bronchus. I would say that the most likely diagnosis is carcinoma, despite the age of the patient, because it is a common lesion, but I could not discard the other options. A CT is indicated.

Click here to see more images

Unenhanced CT was done. What would be your diagnosis?

1. Carcinoma
2. Benign endobronchial tumor
3. Tuberculosis
4. None of the above

Click here to know the answer

Findings: coronal reconstruction shows obstruction of the RUL (C, arrow). Unenhanced axial slice shows the collapsed lobe with rounded high-attenuation areas within it (D, circle).

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Coronal reconstruction shows high-attenuation branching structures within the collapsed lobe which represent mucous impaction (E, circle). Dense mucus at CT is very characteristic of allergic bronchopulmonary aspergillosis (ABPA), which is the most likely diagnosis.
ABPA is accompanied by chronic sinus disease and facial CT shows marked affectation of both maxillary sinuses (F).

Final diagnosis: RUL collapse secondary to mucous plugs in ABPA

After removal of the plugs by bronchoscopy, the chest shows marked improvement.

Allergic bronchopulmonary aspergillosis is caused by hypersensitivity reaction to Aspergillus organisms. Excessive mucus production and abnormal ciliary function lead to mucoid impaction.
Radiologic manifestations include finger-in-glove images in a bronchial distribution They are related to plugging by hyphal masses with distal mucoid impaction. Occasionally, isolated lobar or segmental atelectasis may occur.
In approximately 30% of patients, the impacted mucus has high attenuation at CT

N.B. For those of you who noticed the similarity with case 232 (azygos lobe pneumonia), I should point some subtle but important differences between both cases:

In case 232 the fissure is convex (unusual in collapse). In the present case is straight.
In case 232 the fissure ends before reaching the hilum. In the present case the fissure ends in the hilum.
In case 232 the hilum is of normal size and the RUL artery is visible (arrow). In the present case the hilum is smaller because the RUL artery is included in the collapse.

Cáceres Corner Case 234 – Vignette

Dear Friends,

Today´s radiographs belong to a 48-year-old woman with aortic stenosis.

Most likely diagnosis:

1. Intrathoracic goiter
2. Aortic arch malformation
3. Neurogenic tumor
4. Any of the above

Click here to see the answer

Findings: PA radiograph shows a left mediastinal mass superimposed on the artic knob (A, arrow). The trachea is not displaced. In the lateral view the mass is in the anterior/middle mediastinum (B, arrows).
Regarding the diagnosis offered, the location excludes neurogenic tumor which usually arises in the posterior mediastinum. Intrathoracic goiter is a possibility, but the fact that part of it is the anterior mediastinum and that there is no tracheal displacement goes against this diagnosis. The location of the mass around the aortic knob plus knowing that the patient has aortic valve stenosis point to an aortic arch malformation.

Click here to see more images

Enhanced CT shows that the mass corresponds to a high aortic knob (C, arrow). An oblique view demonstrates the high knob (D, arrow) with a kink and angulation of the aorta representing the lower knob in the PA radiograph (D, red arrow).
My apologies for showing only 3-D images, but the CT was done during the lockdown and they are all I could get.
The patient has no collateral circulation. He had no systemic hypertension and no gradient across the zone of kinking.

Final diagnosis: aortic pseudocoarctation

Pseudocoarctation of the aorta occurs when the aortic arch originates from the 3rd arch, instead of the 4th. In this condition, the aortic arch is higher than usual, with a kinking at the union of the aortic arch and descending aorta, simulating aortic coarctation. Rib notching is absent and systemic hypertension is not present.
This is a rare condition is, but it is not unusual to see it in clinical practice.

To compensate for the lack of CT images in this case, I am showing another pseudocoarctation with similar findings (Fig 1).

Fig 1. PA chest radiograph shows a superior middle mediastinal mass (A, arrow), displacing the trachea. Mass is vaguely seen on the lateral view (B, circle). The most common diagnosis should be an endothoracic goiter but remember that a vascular structure should be always ruled out with enhanced CT.

Coronal CT demonstrates that the mass corresponds to a dilated aortic arch located higher than usual (C, arrow). On the oblique reconstruction, the high aneurysmatic aortic arch is well seen as well as the kinking at the junction with the descending aorta (D, red arrow).
Final diagnosis: aortic pseudocoarctation with aneurysm of the aortic arch.

Cáceres Corner Case 233 – Vignette

Dear Friends,

Recommendations for this week: A history of the world in 100 objects written by Neil McGregor, Director of the British Museum. Series: Good omens (Amazon). 

Today’s radiographs belong to a 51-year-old man with moderate cough.
Do you see any abnormality?
If so, where?

1.  Upper third
2. Middle third
3. Lower third
4. Don’t see it

Click here to see the answer

Findings: PA radiograph shows a left parahilar opacity (A, arrow), seen as an anterior elongated opacity in the lateral view (B, arrow). Its shape in the lateral view suggests mucous impaction.

Click here to see more images

Enhanced CT was done. What would be your diagnosis?

1. Benign endobronchial tumor
2. Allergic aspergillosis
3. Foreign body
4. None of the above

Click here to see the answer

Findings: enhanced axial CT shows an endobronchial obstruction with a distal mucous impaction (C, arrow), also visible in the coronal reconstruction (D, arrow). The clue to the diagnosis lies in recognizing two small lung nodules in the axial view ( C, red arrows) and another one in the right lung in the coronal view (D, red arrow). In addition, there is an enhancing nodule in the gallbladder (D, yellow arrow). These findings suggest widespread malignancy and the correct answer should be 4. None of the above.

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Bronchoscopy discovered a dark tumor in the lingular bronchus (E), as well as numerous small implants in the trachea, also visible in the CT (F, arrow).
Review of the clinical history discovered that the patient had been operated on for melanoma of the back four years earlier.

Final diagnosis: widespread metastases from melanoma, one of them causing bronchial mucous impaction

Mucous impactions may be multiple or localized. Multiple impactions are related to respiratory diseases that cause bronchiectasis and thick mucus (allergic aspergillosis, cystic fibrosis) whereas localized ones are secondary to segmental endobronchial lesions.

The prevalence of bronchogenic carcinoma makes it the most common cause of localized mucus impaction in clinical practice. Other malignant tumoral lesions are metastases and carcinoids.

Endobronchial metastases represent about 2% of lung metastases. They are usually accompanied by metastatic nodules. They may occur in association with any tumor, but the most common sources are colon, breast, kidney and melanoma.

Cáceres Corner Case 232 – Vignette

Dear friends, today I am showing radiographs of a 43-year-old man with fever.


1. RUL pneumonia
2. RUL collapse
3. Mucous impaction
4. None of the above 

Click here to see the answer

Findings: There is a triangular pulmonary opacity in the upper lung that at first glance looks like RUL collapse, limited by the minor fissure (A, arrow). There are two important negative findings against collapse : the right hilum is not elevated and the trachea is not displaced to the right. Also the lateral view does not show any signs of RUL collapse. A careful look discovers a trigone in the upper part of the fissure (A, red arrow), raising the possibility of pneumonia within an azygos lobe.

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The patient was treated with antibiotics. A radiograph three weeks later shows complete resolution of the pneumonia and an azygos lobe (C, arrow).

Final diagnosis: Pneumonia in an azygos lobe simulating RUL collapse

I am showing this case to emphasize the importance of negative findings. In this patient they lead to a reevaluation of the image, leading to the discovery of the azygos fissure.

A correct diagnosis avoids unnecessary and potentially expensive additional procedures. Three years ago I was abroad and had an unenhanced abdominal CT which gave an equivocal diagnosis, leading to a three-days hospital stay and a hefty bill.

Cáceres Corner Case 231 – Vignette

Dear Friends, 

Recommendations for this week: The apartment directed by Willy Wilder (any of his pictures are excellent). A book: Lonesome dove by Larry McMurtry. Both of them are oldies, but very good.

Today’s case: radiographs of a 60-year-old woman  in whom a chest abnormality was discovered during initial workup for breast carcinoma.


1. McLeod syndrome
2. LLL collapse
3. Agenesis of left pulmonary artery
4. None of the above

Click here to see the answer

Findings: PA radiograph shows a hyperlucent left lung with loss of volume. The left hilum is descended and hidden behind the cardiac silhouette (A, arrow). The heart is rotated to the left showing a straight left heart border. There is an ill-defined opacity behind the heart shadow (A, red arrow).
In the lateral view there is an ill-defined opacity in the posterior lower lung (B, arrow) and blurring of the left hemidiaphragm.
Al these findings are typical of LLL collapse with compensatory overinflation of the left upper lobe.

Click here to see more images

Enhanced CT of the chest was obtained. What would be your diagnosis?

1. Hamartoma
2. Carcinoid
3. Endobronchial metastasis
4. Any of the above

Click here to see the answer

Findings: Coronal CT shows marked LLL collapse with bronchiectasis (C, arrow). Coronal MIP shows a rounded mass at the origin of the LLL bronchus (D, circle). Mediastinal window demonstrates popcorn calcifications in a low-enhancing mass (E, circle).

Of the diagnoses offered I believe endobronchial metastasis can be excluded because of the coarse calcification of the nodule.
The differential diagnosis lies between hamartoma and carcinoid. Both may appear as rounded masses with calcification. Endobronchial carcinoids are far more frequent than endobronchial hamartomas, but they usually have higher contrast enhancement.
When I saw the images, I favored hamartoma, but I was wrong. Biopsy and subsequent surgery discovered a carcinoid tumor.

Final diagnosis: Type I carcinoid tumor causing collapse of LLL with bronchiectasis.

I chose this case because it is a nice example of LLL collapse. It is also interesting that a slow-growing process may cause severe collapse without significant symptoms.

Cáceres Corner Case 230 – Vignette

Dear friends,

Today’s radiographs belong to a 27-year-old with dyspnea.


1. Giant bulla
2. Emphysema
3. Loculated pneumothorax
4. Any of the above

Click here to see the answer

Findings: PA radiograph shows overinflation of the lower right lung pushing the minor fissure upward (A, arrow), simulating partial RUL collapse. In the lateral view there is a circular line (B, red arrows) suggesting the wall of a giant bulla. The correct diagnosis is made by detecting overinflation of the left lower lung and scarce vascularity, an indication that we are not dealing with localized disease of RLL (giant bulla or pneumothorax) but with disease of both lower lobes. Therefore the correct diagnosis should be 3. Emphysema.

Another finding in favor of emphysema of lower lobes is redistribution of the pulmonary circulation in which the diameter of the vessels of upper lobes (B) is larger than those of the lower lobes (C).
Pulmonary vascular redistribution is usually due to cardiac failure but it may also occur in emphysema of lower lobes in which vascular flow is redirected to the functioning upper lobes.

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Unenhanced axial CT confirm the relative sparing of upper lobes (D) and the severe emphysematous changes of lower lobes (E).

Coronal CT (F) shows severe emphysema of lower lobes and increased vascularity of upper lobes as well as discrete bronchial dilatations. Sagittal reconstruction demonstrates that the apparent wall of a bulla seen in the lateral chest radiograph represents the minor and major fissures (G, arrows) limiting a markedly emphysematous right middle lobe.

Diagnosis: Pulmonary emphysema secondary to alpha 1 antitrypsin deficiency.

This condition affects young persons and causes severe emphysema of lower lobes and bronchial dilatations.

I am showing this case because is a good example of satisfaction of search (missing changes of the left lower lobe will lead you to the wrong diagnosis).
It is also a nice example of vascular redistribution secondary to pulmonary disease.

Cáceres Corner Case 229 – Vignette

Hello friends,

After three weeks of confinement I believe I have seen all TV series available. If you like Sci-Fi I recommend The Expanse (Amazon Video) and for older citizens The Kominsky method(Netflix).

Today’s case was sent to me from my hospital in the early days of lockdown. The scout film belongs to a 78-year-old man with doubtful COVID-19 infection.
Do you see any abnormality?
If so, where is it?

1. Chest
2. Abdomen
3. Chest and abdomen
4. Don’t see it

Click here to see the answer

Findings: There is a rounded right mediastinal opacity at the junction of the trachea and right main bronchus (A, arrow). There is an apparent abdominal RUQ mass (A, red arrows) with an area of lesser opacity in the center (A, yellow arrow).
The correct answer would be number 3. Visible abnormalities in chest and abdomen

With these findings what would be your diagnosis?

1. Enlarged azygos arch
2. Azygos continuation of IVC
3. Right-sided stomach
4. All of the above

Click here to see the answer

The clue to the diagnosis resides in the apparent RUQ abdominal mass. The shape suggests a right-side stomach, with air in the antrum and duodenal bulb and lesser amount of air in the fornix (Fig A). Findings are better seen in the drawing (B).

A right-sided stomach with a normal-positioned heart is highly suggestive of a congenital abnormality, levocardia with abdominal situs inversus. In this malformation the chest structures are in their normal location, whereas the abdominal viscera are rotated 180 degrees.
This malformation is accompanied by partial interruption of the IVC and azygos continuation, which results in an enlarged azygos arch.
Therefore the correct answer is 4. All of the above

Click here to see the more images

Enhanced axial CT confirms the enlarged azygos arch (A, arrow). Coronal reconstruction demonstrates the dilated ascending azygos vein (B, arrows)

Axial images of the upper abdomen show the gastric fornix in the RUQ (C-D, arrows) as well as a normal left-sided heart (C) and a mid-line liver (D). There is a small splenic remnant in the RUQ (D, red arrow).

Final diagnosis: Levocardia with abdominal situs inversus

I am showing this case because this is our fourth patient with levocardia and abdominal situs inversus seen in the last four years (see Caceres´ corner cases 178 & 194 and Dr. Pepe´s Summer case 1). It may not be as rare as the textbooks state. In addition, the diagnosis can be suggested in the plain film if we discover the right-sided stomach.

Cáceres Corner Case 228 – Vignette

Dear Friends,

Today I am showing a preoperative chest radiograph for varices of a 60-year-old woman.
Do you see any abnormality?
If so, where is it?

1. Lung
2. Mediastinum
3. Pleura/chest wall
4. Don’t see it

Click here to see the answer

Findings: There are bilateral convex opacities in the lower mediastinum (A, arrows), better seen in the cone down view (B, arrows). The appearance suggests a lower central mediastinal mass and the most likely diagnosis should be hiatus hernia. A fact against this diagnosis is the gastric fornix in its normal location (A, red arrow).

What would you recommend:

1. Lateral view of the chest
2. Esophagogram
3. Chest CT
4. None of the above

Click here to see the answer

In my opinion, the best choice is a lateral view, which shows poor definition of the body of the eleventh dorsal vertebra with a sharp angulation of the spine (C, circle). There is no evidence of hiatus hernia.

Click here to see the more images

AP cone down view of the lower thoracic spine shows a butterfly deformity of D11 (D, circle) with the outer borders accounting for the convexities visible in the chest radiograph. Lateral cone down view confirms marked flattening and collapse of the vertebral body (E, circle)

The patient had been involved in a car accident five years ago resulting in a burst compression fracture of D11. Comparison with previous radiographs did nor show any change.

Final diagnosis: Traumatic compression fracture of D11, stable

Teaching point: Remember that not all opacities in the lower mediastinum in the PA view are hiatus hernias. A lateral view places them in the correct compartment and helps to clarify the etiology.

Cáceres Corner Case 227 – Vignette

Dear friends, starting today I plan to show simple teaching cases (vignettes) hoping to ease the boredom of the confinement.
I will show two cases every week (Monday and Thursday). To make the presentation more agile the diagnosis will be included. If you get impatient all you have to do is press the answer button.

The first case is a routine control PA radiograph in a 67-year-old woman operated on for breast carcinoma three years ago.

Question: Do you suspect any bone metastasis?

Click here to see the answer

Findings: There is an apparent lytic lesion in the distal end of the right clavicle (A, arrow), better seen in the cone down view (B, arrow).

When I saw this case two months ago, I could not determine whether the lesion was real or not. What would you do?
1. Compare with previous films
2. Call the oncologist
4. Bone scintigraphy

Click here to see the answer

In my opinion, the first thing to do was comparing with previous films although
this brilliant idea was hampered by the technician placing the marker in top of the distal clavicle in two earlier radiographs (C-D).

What would you do now?
1. Bone scintigraphy
2. Call the oncologist
4. CT

Click here to see the answer

Since I was not sure about the lesion, I decided to call the oncologist to find out if she suspected any metastasis and if the patient had any pain in the right acromioclavicular area. The answer was negative. What would you recommend?

1. Bone scintigraphy
2. CT
4. Radiograph of the right clavicle

click here to see the answer

In my opinion the fastest way to clarify the diagnosis was to take a radiograph of both clavicles (with the left for comparison). The distal end of the right clavicle has a normal appearance and , since the patient had no local symptoms, no further studies were needed.

Final diagnosis: normal variant simulating pathology in an oncologic patient

I have seen several chest radiographs with apparent lytic lesion of the distal clavicle that turned out to be normal. It is described in the Atlas of normal variants by Keats. In this case I was doubtful because the patient had a carcinoma and the appearance of the lesion was ominous.
There are two teaching points in this case:
1. Talking to the referring physician is important to determine the management of findings.
2. A simple and inexpensive procedure clarified the diagnosis and avoided unnecessary additional studies.

Cáceres’ Corner Case 226 – SOLVED

Dear Friends,

Today’s radiographs belong to a 27-year-old woman who came for a routine check-up.

Most likely diagnosis:

1. Thymic tumor
2. Enlarged lymph nodes
3. Aortic arch malformation
4. None of the above

CT images will be shown next Wednesday.

Click here to see the first images

Dear Friends,

Today I am showing enhanced CT images of the mediastinum in the early (A-B) and late phases (C-E).
What do you think?

Click here to see more images

Click here to see the answer

Findings: PA chest radiograph shows a right upper mediastinal mass with undulated border (A, arrow). There is increased opacity of the anterior clear space in the lateral view (B, circle). In my opinion, the most likely diagnosis would be thymic tumor, although the undulated border favors enlarged lymph nodes.

Enhanced axial CTs in the arterial phase show an anterior mediastinal mass with minimal enhancement (C-D, arrows) and a vascular space in the center (C, yellow arrow).

Coronal and axial CTs in the late phase show partial washout of the vascular space (E, yellow arrow). The clue to the diagnosis lies in the presence of several punctate calcifications within the mass (F-G, red arrows) consistent with phleboliths, which are practically diagnostic of hemangioma. The central vascular space also supports the diagnosis.

The patient had been diagnosed of mediastinal hemangioma two years earlier and comparison with previous chest films and CTs did not show any change.
Final diagnosis: Mediastinal hemangioma
Congratulations to Naegleria and MK who gave similar diagnosis both at exactly 12:55 P.M.
Teaching point: This case is unusual (I have seen only two of them in the mediastinum) but can be easily diagnosed if phleboliths are present (and recognized). Early in my residency I learned that, when finding phleboliths within a mass, the diagnosis should be hemangioma until proven otherwise.
Ref. HP McAdams, ML Rosado de Christenson, CA Moran. Mediastinal hemangioma: radiographic and CT features in 14 patients. Radiology 1994; 193:399-402