Cáceres’ Corner Case 256 – SOLVED

Dear Friends,

welcome to the second trimester of 2021! Showing today PA chest radiograph of a 66-year-old man with chest pain without any other symptoms.

What do you see?
More images will be shown on Tuesday and Wednesday.

Dear friends, showing today the lateral chest view.
Does it help?

Today I am showing an enhanced axial CT.
What would be your diagnosis?

Click here to see the answer

Findings: PA chest radiograph shows an increase in size and opacity of the left hilum
(A, arrow), due to superimposition of a well-defined posterior mass visible in the lateral view (B, arrow). At first glance, the appearance of the mass is compatible with an extrapulmonary lesion. However, there is retrocardiac nodule in the PA view (A, red arrow), suggesting a metastasis from an intrapulmonary mass.

Enhanced axial CT confirms an irregular pulmonary mass (C, arrow), which is invading the chest wall, as confirmed by the displaced intercostal artery (C, yellow arrow) and erosion of the underlying rib (D, circle).

Caudal slices confirm the retrocardiac nodule (E, white arrow) and additional nodules (E-F, red arrows) representing pleural implants.
Biopsy of the main mass returned as lung carcinoma.

Final diagnosis: Carcinoma of the lung simulating an enlarged hilum in the PA view.
Congratulations to Dr LeLam and thaf1212, who detected the retrocardiac nodule, which is the clue to determine that the main mass is intrapulmonary.
Teaching point: Remember that one of the three causes of unilateral enlarged hilum is superposition of a pulmonary opacity either in front or behind the hilum (the other two are enlarged hilar lymph nodes and increase in size of the pulmonary artery)

Dr. Pepe’s Diploma Casebook 170 – SOLVED

Dear Friends,

This week’s case follows the pattern of a “Meet the Examiner” presentation, with questions and answers similar to a real examination. Take your time before scrolling down for the answer.

There will be no new blog posts over the Easter period. The next case will be published on Monday, April 5, 2021.

The images belong to a 65-year-old woman with cough and low-grade fever. The referred physician demanded a chest CT.

What would be your diagnosis?

1. Pneumonia
2. Pulmonary infarction
3. Peripheral adenocarcinoma
4. Any of the above

Click here to see the answer

Findings: unenhanced axial and sagittal CTs show LLL airspace disease with a surrounding halo (B-C arrows). In my opinion, the sensible answer is 4. Any of the above, although I liked adenocarcinoma because of the peripheral halo and air bubbles within the infiltrate (A, circle).

Click here to see more images

Patient was diagnosed of pneumonia and treated with antibiotics, without improvement. Chest radiographs taken 13 days later shows progression of the LLL opacity (A and B, arrows).

A CT was recommended.

Click here to see the CT images

Two axial and one sagittal views are selected. What would your diagnosis be:

1. Peripheral adenocarcinoma
2. Tuberculosis
3. Covid pneumonia
4. None of the above

Click here to see the answer

In comparison with the previous CT, the LLL infiltrate has increased markedly in less than two weeks. An upper halo persists (A and C, arrows). A small infiltrate has appeared at the right lung base (B, arrow) In my opinion, this rapid progression rules out carcinoma and TB. A PCR was negative. Blood tests were not remarkable. It was considered that the patient had an unusual pneumonia, and the antibiotic was changed.

Click here to see more images

The fever disappeared with the new antibiotic and the patient improved moderately. A new CT was taken three weeks later. What would your diagnosis be?

1. Löffler syndrome
2. Goodpasture syndrome
3. Cryptogenic organizing pneumonia
4. Any of the above

Click here to see the answer

Findings: The most striking finding is the disappearance of the LLL infiltrate and the apparition of two new areas of airspace disease in RLL and LLL (A, arrows). There is a halo sign in the LUL infiltrate (B, arrows) and a negative halo in the RLL infiltrate (B and C, arrows).
This change of location of the opacities falls in the category of migratory infiltrates which are caused by several diseases, some of them listed in the previous questions.

The patient had no risk factors for parasitic infection and no peripheral eosinophilia, ruling out Löffler syndrome. Renal function was not altered, excluding Goodpasture’s syndrome

The combination of migratory infiltrates and a negative halo sign was very suggestive of a cryptogenetic organizing pneumonia, that was confirmed with BAL and an excellent response to corticosteroid treatment.

Final diagnosis: cryptogenic organizing pneumonia

Organizing pneumonia (OP) is a clinical, radiological and histological entity usually associated to other pathologies. The idiopathic form of OP is called cryptogenic organizing pneumonia (COP).
Clinical manifestations of COP begin with a mild flu-like illness with fever, cough and malaise.
In chest imaging it may appear as localized airspace opacity that may be confused with ordinary pneumonia, adenocarcinoma or aspiration, among others. The lack of response to antibiotic treatment and the peripheral location may help in suggesting the diagnosis.

I am presenting this case because it shows two features the help in the diagnosis: migratory infiltrates and the reverse halo sign.
Migratory infiltrates are not unique to COP, but they occur in a limited number of diseases (Loeffler syndrome, vasculitis, etc.) and their presence in the adequate clinical setting should suggest COP.
The reverse halo was originally described as specific of COP, but since then it has been seen in many other entities. It is defined as a central ground-glass opacity  surrounded by denser consolidation of crescentic shape or a complete ring. It is visible in about 20% of cases.

In this patient the combination of both signs strongly pointed towards COP, that was confirmed and responded brilliantly to corticoid treatment.

To complete the presentation, I am showing two more examples of reversed halo and migratory infiltrates (CASES 1 and 2, below).

CASE 1. 61-year-old woman with COP and basilar infiltrates (A, arrows). During treatment, coronal and axial CTs show bilateral and symmetrical reversed halo signs (B and C, arrows)

CASE 2. 51-year-old woman with COP and migratory pulmonary infiltrates (A and B). The second CT shows nice examples of reversed halo sign (B, circle), better seen in the cone down axial view (C, arrows).

Follow Dr. Pepe’s advice:

1. Localized cryptogenic organizing pneumonia may mimic other pulmonary processes

2. Migrating infiltrates and reverse halo sign (or both) are helpful in suspecting COP

Cáceres’ Corner Case 253 – SOLVED

Dear Friends,

Today’s case is a PA chest radiograph for knee surgery in a 28-year-old man.

What do you see?

Click here to see the answer

Findings: PA chest radiograph shows an osteochondroma in the right humerus (A, yellow arrow). There are two more in the anterior arch of the left fifth rib and in the proximal end of the right clavicle (A, red arrows).
They are better seen in the cone down views (B-D, arrows).

The first and only diagnosis that comes to mind is multiple osteochondromatosis, confirmed with views of the lower extremities (E-G).

Final diagnosis: Multiple osteochondromatosis.
Most of you did very well in this case. Congratulations to Mauro, who was the first and to Kaushalya and Ali who made back-to-back diagnosis in a five-minute interval.
Teaching point: remember to look at the bones of the chest, especially when taking an examination. It may surprise the examiner and win you a few extra points.

Cáceres’ Corner Case 248 – SOLVED

Dear Friends,

today I am showing preop radiographs for knee surgery of a 71-year-old man.
What do you see?

More images will be shown on Wednesday.

Click here to see new images

Dear friends, showing additional images of the sternum taken six years earlier, in 2014.
What do you think?

Click here to see the answer

Findings: PA chest is unremarkable (A). The lateral radiograph shows an expanding lytic lesion in the sternal manubrium (B, circle).

Cone down view shows the lesion better (C, arrows). Sagittal, coronal and axial unenhanced CT taken six years earlier (2014) demonstrate that the cortical bone is broken in several places, suggesting an aggressive process (D-F, arrows). A soft-tissue mass is not visible.

No other skeletal lesions were found. Biopsy of the sternum confirmed the diagnosis of solitary myeloma (plasmocytoma), that was subsequently treated. The patient remained asymptomatic.
Final diagnosis: Plasmocytoma of the sternum
Congratulations to Priyanka Chhabra and Olena, who made the correct diagnosis. And kudos to all of you who saw the lesion in the lateral chest radiograph.
Teaching point: Remember that a lytic lesion of the sternum in an adult is malignant until proven otherwise. Main etiologies are primary tumors (chondrosarcoma) and metastases.

Reviewing the literature, I found a case report with similar findings: Solitary plasmacytoma of the sternum with a spiculated periosteal reaction: A case report. ONCOLOGY LETTERS 9: 191-194, 2015

Cáceres’ Corner Case 246 – SOLVED

Dear Friends,

Today I am showing the PA radiograph of an 82-year-old woman. Preoperatory for cataracts.

What do you think about the right hilum?

1. Calcified TB nodes
2. Sarcoidosis
3. Amyloid
4. None of the above

More images will be shown on Wednesday.

Click here to see the images shown on Monday

Dear friends, showing today PA and lateral radiographs taken two years earlier. Hope they help.

Click here to see the new images

Click here to see the answer

Findings: Initial PA radiograph shows opacities in the right hilum (A, circle), unchanged in comparison with a previous film taken two years earlier (B, circle).

The clue to the diagnosis lies in the density and appearance of the opacities. They are denser than the typical lymph node calcifications, suggesting that they are metallic. In addition, some of them look tubular or branching (C, red arrows). A lateral view taken two years earlier confirms dense lineal and branching opacities in right lung (D, arrows).
The combination of linear and branching metallic opacities suggests that they are either in the bronchi (previous bronchography) or within the pulmonary vessels (embolism after vertebroplasty o treatment of AV malformation). See Diploma # 44.

Lateral view of the lumbar spine shows surgical changes with vertebroplasty of L3 to L5 and leakage of the cement into the epidural veins (E, arrows), better seen in the sagittal CT (F, arrows).

Unenhanced CT confirms multiple cement emboli in the pulmonary arteries (G-J, circles)

Final diagnosis: cement embolization of the lung after vertebroplasty
I must mention Olena and Ayudi who suggested amyloid and broncholithiasis but failed to notice the metallic opacity of the findings.
Teaching point: Consider previous vertebroplasty when you see metallic opacities in the lungs. It is a common complication.

Dr. Pepe’s Diploma Casebook 161 – Meet the examiner

Dear Friends,

This week’s case follows the pattern of a “Meet the Examiner” presentation, with questions and answers similar to a real examination. Take your time before scrolling down for the answer.

The images belong to a 60-year-old man with moderate cough and dyspnea

What would you recommend?

1. Compare with previous films
2. Chest CT
4. None of the above

Click here to see the answer

Findings: PA radiograph shows large bullae in both upper lobes. There is a nodule in the RUL projected over one bulla (A, arrow). Two small calcified granulomas are visible in the periphery of the LUL (A, circle). PA film taken five years earlier (B) does not show any nodule in the RUL. The granulomas in the LUL are unchanged.

Report of the chest : bullous emphysema with a nodule not visible in 2014. Given the relationship between bullous disease and carcinoma, it is imperative to do a chest CT.

Enhanced CT was done the next day. What would you suggest?

1. Antibiotic treatment and CXR in one month
3. Antibiotic treatment and CT in one month
4. None of the above

Click here to see the answer

Findings: aside form large bullae in both upper lobes, an irregular nodule is evident in the RUL (A-B, arrows). In my opinion, given the appearance of the nodule I would suspect malignancy and request a PET-CT. However CT was reported as: Pseudonodular opacity in RUL that could be related to an infectious/inflammatory process. A neoplasm cannot be excluded. Recommend control after treatment

Click here to see more images

A chest radiograph was taken one month later.
What would you do?

2. CXR in three months
3. CT in three months
4. Control in one year

Click here to see more images

The chest radiograph one month later was reported as unchanged and no further suggestions were made by the radiologist. The clinician took no further action.

The patient came back ten months later, and a new radiograph showed an obvious increase in size of the nodule (B, arrow) when compared to the initial film (A, arrow)

Click here to see more images

Enhanced CT confirms the increase in size of the nodule (A-B, arrows). Surgery discovered a carcinoma in the wall of a bulla.

Final diagnosis: adenocarcinoma of the lung associated to bullous disease.

Lung carcinoma seems to occur more often in bullous disease, although there is not enough evidence compiled at the present time. Despite the lack of evidence, knowing
this association may prevent misdiagnosis.
A lesser known fact is that the cystic space may disappear after the carcinoma develops, as occurred in a second case (see below). Spontaneous regression of a bulla may be due to non-malignant causes, but carcinoma should be excluded with CT because it may take years for the lesion to be visible in the chest radiograph.

I am showing this case because the opinion given in the chest radiograph was unequivocal, whereas the CT report was vapid, giving the impression that the nodule was infectious, and that malignancy was less likely. The follow-up radiograph was disregarded by the radiologist and clinician and this caused a delay in diagnosis of almost one year.

To complete the information, I am showing a second case of carcinoma developing in the wall of a cystic space

Images of the second case were obtained during routine CT screening in a 72-year-old man, heavy smoker.
Apical axial CT image shows a small nodule in the LUL (A, arrow), with increased uptake on PET-CT (C, arrow). There is a cystic airspace in the LLL (B, arrow) with no PET-CT uptake, interpreted as a non-specific cystic airspace lesion.

At surgery a carcinoma of the LUL was found.

It was decided to continue with yearly follow-up studies. The cystic air space (A, arrow) increased in size in 2008 but still had a thin wall (B, arrow). In 2009 it has decreased slightly in size and the wall is thicker than the previous year (C, arrow). A new PET-CT shows increased uptake in the posterior wall (D, arrow).

Malignancy was suspected. The patient refused further surgery or percutaneous biopsy and it was decided to do a follow up study three months later.
Axial CT shows that the cystic airspace has disappeared and in its place, a solid mass has developed (A and B, arrows) with increased overall uptake on PET-CT (C, arrow). At surgery, an adenocarcinoma was found.

Final diagnosis: adenocarcinoma arising in the wall of a cystic airspace, which disappeared as the tumour progressed.

Follow Dr. Pepe’s advice:

1. Bullous emphysema and isolated cystic spaces may be associated with an increased incidence of carcinomas

2. A poorly worded report may cause an unnecessary delay in diagnosis

Dr. Pepe’s Diploma Casebook 160 – With a webinar! – SOLVED

Dear friends, I am starting a new webinar series entitled “Things that we already know, but are important to remember”. The objective is to refresh basic concepts that often are forgotten.

This week’s webinar title is “Who is afraid of the bad, big lateral chest”. The webinar will take place on Wednesday, September 30 at 12:00 CEST. You can register here.

The initial case is a PA chest radiograph of a 61-year-old man with hemoptysis.

Do you see any abnormality?
1. Yes
2. No
3. I want a lateral chest

Register for the webinar and lear more about this case and others!

Click here to see the answer

Findings: PA radiograph (A) does not show any significant findings. The lateral view shows a posterior pulmonary nodule with irregular contour (B, arrow). A typical donut sign is visible (B, circle), indicative of enlarged subcarinal lymph nodes.

Enhanced axial CT and PET-CT show confirm the pulmonary nodule (C-D, arrows) and the subcarinal lymphadenopathies (C-D, red arrows).

Final diagnosis:

Carcinoma hidden in the PA view behind the right hilum with metastases to subcarinal lymph nodes.
Congratulations to drpeca who was the first to want a lateral view.
Teaching point: remember that about 26% of the lung is hidden in the PA view. A lateral chest radiograph is indispensable to study the chest.

Cáceres’ Corner Case 242 – SOLVED

Dear friends, welcome back!

Today I am showing a straightforward case to ease you into the new season. Promise I will not mention Covid-19 at all.

Today’s case is a pre op PA radiograph for knee surgery in a 47-year-old woman.

What do you see?

Come back on Friday to see the answer!

Click here to see the answer

Lung and mediastinum do not show any relevant findings. An isolated air-fluid level is visible in the left upper quadrant of the abdomen (A, arrow). The inner border of the cavity is smooth. The gastric bubble is visible under the left hemidiaphragm (A, red arrow).

Given that the patient is asymptomatic, an abdominal abscess or bowel obstruction/ volvulus can be safely excluded. A large intestinal diverticulum could be a possibility. I suspected a more mundane diagnosis: a review of the clinical history discovered that an intragastric balloon had been inserted fourteen months earlier.

Final diagnosis: air-fluid level in an intragastric balloon for morbid obesity
Congratulations to all of you who detected the air-fluid level. Kudos to Flemming Ghomsen who came close to the diagnosis.

Intragastric balloons for bariatric surgery may be filled with air or with saline. In the second case they may present an air-fluid level due to room air mixing during the injection of fluid.

Teaching points:

1. Remember to look under the diaphragm. You may discover interesting findings.
2. In your differential diagnosis always include iatrogenesis as a possible cause.

Dr. Pepe’s Diploma Casebook 158 – SOLVED

Dear Friends,

this is the last case of the first semester. Will meet again in September.
Wish all of you a very happy summer vacation!

This is a new “art of interpretation” case. Radiographs belong to a 40-year-old woman with mild cough.

What do you see?


1. Chronic TB changes
2. AV malformation
3. Bronchial atresia
4. Any of the above

Click here to see the answer

To refresh your memory, remember that interpreting a chest radiograph involves three basic steps:

1. Gather information. Examine the radiographs carefully and collect all the pertinent information. Remember that overlooking visible findings is the main cause of errors.

2. Analyze the findings. Once collected, the findings should be properly evaluated, and an opinion should be offered.

3. Decide on the next step to reach the diagnosis.

Step 1. Information:

In this patient the lateral view is unremarkable.
All relevant findings are seen in the PA radiograph:

1. Tubular branching opacities in the left upper lung (A, red arrows)
2. Increased lucency of left upper lung (A, circle)
3. Negative finding: the left hilum is in its normal position.

Step 2. Analysis of the findings:

1. Branching tubular opacities have a limited differential diagnosis: either they are pulmonary vessels or mucous-filled dilated bronchi.

2. Hyperlucent lung is a reliable sign of lung disease when complemented with an expiration film to demonstrate air-trapping.

3. The normal position of the left hilum is a negative finding that excludes a fibrotic process in the LUL (I.e. chronic TB), which should cause upper retraction of the hilum.

The combination of a lucent lung lesion with branching tubular opacities points towards an obstructive process of a segmental bronchus with mucous impaction (Obstruction of a lobar bronchus would cause lobar collapse instead of increased lucency).


Step 3. Decide on the next step

Once segmental bronchial obstruction is suspected in the chest radiograph, the best procedure to confirm it is an enhanced chest CT with expiratory views. In this case it shows attenuated upper lobe vessels (B, arrows) and obvious mucous impactions (B-C, red arrows).
Axial CT with lung window confirms the increased lucency of the apical-posterior segment of the RUL (D, circle)

Inspiration/expiration axial CT views (E-F) confirm segmental air trapping on the left.

Bronchoscopy did not show any inflammatory or tumoral changes in the LUL bronchus. The orifice of the apical-posterior segment was missing.

Final diagnosis: bronchial atresia of apical-posterior segment of LUL

In my experience, bronchial atresia is the most common congenital lung malformation seen in adults. Congenital bronchial atresia results from proximal interruption of a segmental bronchus, which causes overinflation of the affected segment and secondary mucus impaction. Chest radiography shows a focal hyperlucent area with internal mucus impaction. CT depicts these findings to better advantage. Inspiration and expiration views help to confirm air-trapping. In case of doubt, bronchoscopy excludes other causes of bronchial obstruction.

Congenital bronchial atresia may present different appearances, as shown in the following case of one of our X-ray technicians.

30-year-old female, asymptomatic. PA chest radiograph (A) shows hyperlucent left lung with discrete dextroposition of the heart. Expiration film (B) shows air-trapping on the left with deviation of the mediastinum towards the right. Note a thick tubular shadow in the left lower lung (A-B, red arrows), compatible with bronchial impaction. The findings are suggestive of congenital bronchial atresia

Axial and coronal enhanced CT show increased lucency of the posterior segments of LLL with a central mucous impaction (C-D, red arrows)

Decreased vascularity of LLL and central mucous impaction (E-F, red arrows) are better demonstrated in the MIP reconstruction.

Coronal view eleven years later show that air is now present within the dilated bronchus, confirming the diagnosis (G-H, circles) .

Dr. Pepe’s teaching point:

Hyperlucent lung with mucous impaction are the hallmark of congenital bronchial atresia.

Cáceres’ Corner Case 241 – SOLVED

Dear Friends,

Today’s radiographs belong to a 24-year-old woman with cough and fever. What do you see?

More images will be shown next Wednesday and the answer will be published on Friday.

Click here to see Monday images

Dear Friends,

Showing today CT images of the chest. What do you think?

Click here to see the new images

Click here to see the answer

Findings: Chest radiographs show air-space disease in the right lower lobe (A-B, arrows). There is marked widening of the right paratracheal line (A, red arrow) suggestive of mediastinal lymphadenopathy.

Axial CT with lung window shows RLL air-space disease without cavitation (C, arrow). Mediastinal window at different levels confirms enlarged paratracheal, subcarinal and neck lymph nodes with hypodense center (D-F, red arrows). These findings should suggest active tuberculosis as the first possibility.
Although TB usually affects upper lobes, isolated involvement of lower lobes occurs in about 7% of cases.
Mycobacterium tuberculosis was found in the sputum.

Final diagnosis: active TB.
Congratulations to Archanareddyt who was the first to make the diagnosis.
 Teaching point: lymph nodes with hypodense center may occur in several processes (treated tumors, Whipple’s, etc.), but in the appropriate clinical situation, the first diagnostic consideration should be tuberculosis.