Cardiac decompensation-CXR

Elderly person with shortness of breath what is the finding?

There is big heart and generally ill-defined lung fields. On closer examination,  we notice, upper lobar vessels are around 3mm(normal maximum of 2mm) called cephalization has occurred. There are few areas of peribronchial cuffing i.e. there is interstitial fluid accumulated around the bronchi  making them look like doughnuts . Both perihilar regions are hazy and ill-defined suggesting fluid. The appearance  is  classical of  cardiac decompensation.

Teaching points by Dr MGK Murthy

·         Left atrial pressure measure is quite represented by X ray appearance. Normal being 5-10 mm Hg, cephalization(10-15),Kerley B lines (15-20),interstitial edema(20-25), an alveolar edema(>25mm Hg)

·         Kerley B lines are 1-2 cms long horizontal bases  lines  and are perpendicular to pleural surface

·         Pulmonary oedema usually clears in about 3days or less. Clearance is usually from periphery to center(because of  emptying effect of breathing and movement )

·         Unilateral oedema may be seen in dependent side if patient lies on one side overnight. Normal vessel to bronchus ratio is upper lobes(0.85), at hila(1.0) and lower lobes (1.35).

Primary Tubercular Complex-Plain CXR

A young child with cough and fever

Chest Xray shows subsgemetnal atelectasis with transverse fissure thickening with hilar lymphadenopathy and mottled infrahilar reticulation possibly lymphangitis – together called primary complex disease(Ranke’s complex)

Teaching points by Dr MGK Murthy

-       Tubercle bacilli as little as 1-3 can reach the respiratory tree  of the child invariably from cavitating adult contact usually at home or school/daycare environment as the bacilli are  really killed by ultraviolet light outside

·       The bacilli can be expelled by the cilia to be swallowed and destroyed by the stomach acid or can reach alveoli to be inhibited/killed by the macrophages.

·       If they are virulent , multiply and burst macropahges to spread forming tubercle (aggregation of macrophages, epitheloid cells and lymphocytes)

·       Immune response at this stage(3-8 wks) is delayed hypersensitivity and tuberculin test is positive

·       Bacilli escape from edge, multiply and reach lymphnodes .

·       All the 3 components alveolar site (ghon’s focus), lymphangitis and infected mediastinal lymphnode form Primary complex mediated by cell mediated immunity (Ranke’scomplex)

·       Chest Xray/CT is + by 4-8 wks after the exposure

·       Can involve any part  of the lung but middle lobe is least involved

·       95%do not suffer from disease and X ray  shows only fibrosis, calcification or completely normal

·       Radiological hallmark is lymphadenopathy

·       Because of peculiarity of lymphatics, left parenchymal lesion produces bilateral and right parenchymal shows only right hilar  lymphnodes possibly along with transverse fissure fluid

·       When the lesion erodes the lymphnode and spreads along the bronchus it will become progressive primary TB

·       If TB infection occurs 1 year or later after the original infection, referred to as post primary from usually because of reactivation

·        Post primary prefers colonization in upper lobes specially apical and posterior segments

·       Child to child transmission is rare because of lack of tussive outburst

·       Miliary and Meningeal forms develop in 1st 3months after primary complex

·       Pleural and peritoneal forms take 3-7 months to manifest

·       One variety called congenital TB is extremely rare possibly because  of hypoxic intrauterine environment does not promote TB bacilli growth.

·       But when occurs ,usually via transplacental spread-----primary complex is in liver –periportal LNs –other organs and lungs can remain latent for 2-4 wks after birth and when Xray is +, it shows miliary form

·       Even more rarely can occur by foetus swallowing bacilli in genital TB

Malpositioned Ryles Tube into Left Bronchus

Clinical signs of nasogastric tube malpositioning in intensive care patients may be absent or misleading, chest radiography can accurately detect nasogastric tube malpositions in the tracheobronchial tree, may prevent complications, and avoid the use of further costly or invasive diagnostic techniques. This is a post operative patient in whom ryles tube was placed in OT setting and passage was considered difficult. CXR shows RT with distal end on left bronchus. 

Miliary tuberculosis-CT

Miliary tuberculosis (also known as "disseminated tuberculosis" is a form of tuberculosis that is characterized by a wide dissemination into the human body and by the tiny size of the lesions (1–5 mm). Its name comes from a distinctive pattern seen on a chest X-ray of many tiny spots distributed throughout the lung fields with the appearance similar to millet seeds—thus the term "miliary" tuberculosis.

Cardiac Pacemaker for a General Radiologist

The attached xray shows multiple leads biventricular cardiac pacer in post sternotomy patient with Azygos lobe and possible perihilar oedema.


Cardiac pacemaker for a general radiologist-by Dr MGK Murthy.

 

 

Types of permanent pacing :

• Single chamber cardiac pacers: lead terminates in right ventricle.
• Dual chamber cardiac pacers: leads terminate in right atrial appendage and right ventricular apex.
• Biventricular pacers: Left ventricular epicardial leads are used. The leads go directly to the surface of the left ventricle, and they are usually associated with typical pacing electrodes in the right atrial appendage and right ventricular apex. In other cases, the left ventricular pacing electrodes are introduced through the coronary sinus and wedged into a left ventricular cardiac vein.

Two components
(a) control unit: has lithium battery usually with sense amplifiers to sense the natural heart beats and computer logic to correct

 

(b)leads-number depending on the case, external casing of the control unit is made of inert titanium to avoid any immunological rejections

  

Note --MRI is contraindicated- but on demand pacemakers in future may permit MRI in future

Round Atelectasis

This is a case of treated tubercular pleural effusion with rounded opacity showing characterstic apearance of round atelectasis. The characteristic feature of round atelectasis is the comet tail sign. As the lung collapses, the vessels and bronchi that lead to the mass are pulled into the region. As they reach the mass, they diverge and arch around the undersurface to merge with the inferior pole of the mass.

Further reading--
Radiology. 1999;213:553-554

Dr.Sumer K Sethi, MD

Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers

Editor-in-chief, The Internet Journal of Radiology

Director, DAMS (Delhi Academy of Medical Sciences)