tuberculosis viral infections mediastinum radiology

1. Dr Saket Kumar Jain (Resident)
Dept. Of Radio-Diagnosis
MGM HOSPITAL

2. 
Two types – primary and post primary

Patients who develop disease after initial exposure are considered to
have primary TB .

Primary site of infection in the lungs is called the Ghon focus.

The combination of the Ghon’s focus and affected lymph nodes is
known as the primary complex .

“ Ranke complex ”

3. Patterns
Parenchymal
Primary
Post-primary
Self limiting
progressive
dense, homogeneous
parenchyma consolidation in
any lobe
patchy, poorly defined
consolidation, particularly
in the apical and
posterior segments of the
upper lobes
however, predominance in the
lower and middle lobes is
suggestive of the disease,
especially in adults
in majority- more than
one pulmonary segment
is involved, with bilateral
disease seen in one-third
to two-thirds of cases.
appearance is often
indistinguishable from that of
bacterial pneumonia

4. Cavitations'
primary
Post primary
Rare
Cavitation, the hallmark of postprimary
tuberculosis
typically have thick, irregular walls, which
become smooth and thin with successful
treatment
Are multiple
Lymphadenopathy
is seen in up to 96% of children and
43% of adults
typically unilateral and right sided,
involving the hilum and right
paratracheal region
although it is bilateral in about one-third
of cases
it can be the sole radiographic finding
more common in infants and decreases
in frequency with age
seen in only
about 5% of
patient

5. Pleural effusion
Primary
Post primary
seen in approximately
one-fourth of patients
seen in approximately
18% of patients with
postprimary
tuberculosis
often the sole
manifestation of
tuberculosis
usually small and
associated with
parenchymal disease
very uncommon finding
in infants & is usually
unilateral
effusions are typically
septated

6. Ranke complex

7. Parenchymal primary tuberculosis in an
adult.

12. 
Widespread hematogenous dissemination of
Mycobacterium Tuberculosis

So named because the nodules are the size of millet seeds
(1mm to 3 mm)

Diffuse, random distribution

Takes weeks between the time of dissemination and the radiographic
appearance of disease

When first visible, they measure about 1 mm in size; they can grow to
2-3mm if left untreated

14. 
No matter what form of TB the patient has, it tends to
look like 1° TB

Hilar and mediastinal adenopathy are common

Cavitation is less common

There is no predilection for the apices

Atypical mycobacterium( MAI - mycobacterium aviumintracellulare) is more common in HIV than
Mycobacterium Tuberculosis

15. SARCOIDOSIS
HISTOPLASMOSIS

16. 
Consolidation - ? acute pneumonia .

The term consolidation does not imply any particular aetiology
or pathology .

Acute pneumonia is the commonest cause but not the only cause
of consolidation --- ( other causes include chronic pneumonia,
pulmonary oedema and neoplasm)

17.  what is consolidation ?
Refers to fluid in the airspaces of the lung
Consolidation may be complete or incomplete
The distribution of the consolidation can vary widely.
A consolidation could be described as “patchy”,
“homogenous”, or generalized”.
A consolidation may be described as focal or by the lobe or
segment of lobe affected

19. Batwing sign
Pulonary edema (especially cardiogenic)
pneumonia

23. Air bronchogram refers to the phenomenon of air-filled bronchi
(dark) being made visible by the opacification of surrounding
alveoli (grey - white).

24. 
Micro-organisms responsible may enter the lung by three potential
routes:

via the tracheobronchial tree

via the pulmonary vasculature

via direct spread from infection in the mediastinum, chest wall, or
upper abdomen

25. INFLUENZA
PARAINFLUENZA
Outbreaks in winter
Risk in DM, Elderly, IC
In winter
Self limited
Dry cough, headache,
myalgia, fever, croup and otitis media
Croup , coughing , dyspnea , wheezing ,
tonsilitis, pharyngitis
Superadded bact inf. Can occur
In children with croup may show subglottic
tracheal narowing so called STEEPLE sign
Multifocal patchy consolidation may be
uni/bilateral
Multifocal patchy consolidation may be
uni/bilateral
Plerual effusion uncommon

26. Influenza

28. RSV
MEASLES (RUBEOLA)
Winter & spring
Imp. Cause of both URTI &LRTI in infants &
young children
Year round
In children-URTI- pharyngitis, rhinitis, otitis
media
Fever, myalgia, headache, conjuctivitis
cough
LRTI- coughing, dyspnea, wheezing,
intercoastal retraction
Rhinorrhea followed by skin rash
Perihilar linear opacities , bronchial wall
thickening, patchy areas of consolidation
B/L patchy air space consolidation
associated in perihilar
In children-may be lymph node
enlargement

29. RSV
Measles

30. HERPES SIMPLEX-1
Affects oral cavity ,LRTI occurs if organism is transported into trachea &
bronchi
They are severly immunocompromised
Multifocal consolidation due to bronchopneumonia
• Herpes simplex – 2 – acquired during child birth

31. Varicella zoster virus – pneumonia presents as high fever rapidly
followed by skin rash
Appear as diffuse small nodules in the range of 5-10 mm that progress
to air space consolidation rather rapidly
Hilar lymphadenopathy is common
Pleural effusion is rare

33.  It
is the central compartment of the
thoracic cavity

35. Superior
mediastinum
contents
"BATS & TENT":
Brachiocephalic
veins
Arch of aorta
Thymus
Superior vena
cava
Trachea
Esophagus
Nerves (vagus &
phrenic)
Thoracic duct
Anterior
mediastinum
3 ; T’s
Thymus
Thyroid
Thoracic aorta
Middle
mediastinum
Heart surrounded
by the
pericardium
great vessels :
ascending aorta
superior vena cava
pulmonary trunk
Trachea
bifurcation
Posterior
mediastinum:
contents
“DATES”:
Descending aorta
Azygos and
hemiazygous veins
Thoracic duct
Esophagus
Sympathetic
trunk/ganglia

36. Felsons method of division -
 Anterior,
 Middle,
 Posterior.

38.  RADIOLOGY
• Plain chest x-ray.
• CT of the chest ( procedure of choice for mediastinal
masses )
• MRI (may enhance the diagnostic abilities of chest CT)
▪ FNA or needle biopsy with CT guidance .

39. 
A normal thymus is visible in 50% of pediatric age group of 0–
2 years of age.

The size and shape of the thymus are highly variable

The thymus is seen as a triangular sail (thymic sail sign) frequently
towards the right of the mediastinum. It has no mass effect on
vascular structures or airway.

40. THYMIC SAIL SIGN

41. 
The most common neoplasm of the anterosuperior compartment

Radiograph: small, well-circumscribed mass or as a bulky
lobulated mass confluent with adjacent mediastinal structures

Symptoms:
• chest pain
• dyspnea
• hemoptysis
• cough
• superior vena cava syndrome
• systemic syndromes caused by immunologic mechanisms

43. 
Enlarged thyroid usually are considered retrosternal (also referred to
as mediastinal, intrathoracic, or substernal) when more than 50% of
the thyroid parenchyma is located below the sternal notch

Presentation - Substernal Goiters
Asymptomatic
Choking sensation, particularly in
supine position
Vague chest pain or heaviness
Respiratory
• Dyspnoea
• Orthopnea
• Cough
• Respiratory
distress/insufficiency
• Airway obstruction
Neural
•Hoarseness
•Hemidiaphragm
elevation
Esophageal
•Dysphagia
•Odynophagia

45. 






The mediastinum is commonly involved in lymphoma, either as
part of disseminated disease or less commonly as the site of
primary involvement.
Symptoms
retrosternal chest pain
SVC Compression with SVC SYNDROME
dyspnoea
Cough
PLAIN FILM
A soft tissue mass may be clearly visible, or more frequently the
mediastinum is widened, and the retrosternal space is obscured.

47. 
This is a broad term used to encompass a number of congenital
mediastinal cysts derived from the embryological foregut.

They include bronchogenic, esophageal duplication and
neuroenteric cysts .

Bronchogenic cysts are the most common.

48. Bronchogenic cyst
Esophageal
Duplication Cyst

49. Neurenteric cysts

50. These are congenital out-pouchings from the parietal pericardium

51. A hiatus hernia occurs where there is herniation of stomach through
the esophageal hiatus of the diaphragm
Two types:
Sliding(99%)
Rolling/paraoesophageal(1%)

54. Any cranial nerve may be involved, except CNI
and CN2 which lack sheaths composed of
schwann cells
CN VIII (acoustic neuroma) most commonly the
superior portion of vestibular nerve (most
common)
CN V (2nd most common)
CN VII (3rd most common)
Clinical presentation
Presentation depends on location of the tumor.

55. 
Pneumomediastinum is the presence of extra luminal gas within
the mediastinum. Gas may come from lungs, trachea,
central bronchi, esophagus, and the neck or abdomen.
“Continuous diaphragm sign” of
pneumomediastinum

56. spinnaker sign (also known as the
angel wing sign)

57. TUBERCULOSIS VERY COMMON – HIGH
INDEX OF SUSPICIONCLINICAL PRESENTATION
Its easy to diagnose consolidation but
difficult to interpret it , correlation with
clinical symptoms is the key point
MEDIASTINUM - To diagnose a pathology ,
very difficult - complete work-up
HISTORY , X-RAY + further investigation