medical imaging pathologies

Bennet

• Oblique avulsion# of metacarpal base

 Rolando

Y shaped or comminuted # of metacarpal base

Mallet finger

• distal phalanx

• small bone fragment pulled away by the tendon

Osteoarthritis

• Soft tissue swelling

• Sclerotic margins

• Joint space loss

• Bony cysts

• Bony spurs

boxers fracture

A boxer's fracture is a break in the neck of the 5th metacarpal

joint replacements in fingers

colles fracture

radius tilts posteriorly when its fractured

Smiths fracture

radius tilts anteriorly when fractured

Scaphoid interpretation

• Accounts for more than 60% # of the wrist

• 3 locations

  • Distal pole

  • Waist

  • Proximal pole

• Major blood supply through distal pole

Galeazzi

Distal radius + dislocation distal radioulnar joint

Monteggia

# proximal ulna + dislocation of the radial head

Sail sign

• Raised anterior and/or posterior fat pad on an elbow radiograph

• Indicates joint effusion, possible fracture

Mason classification - radial head fractures

• Type I - no displacement

• Type II - displaced # with separation

• Type III - comminuted

• Type IV - with elbow dislocation

mason classification

distal humerus fractures

FOOSH with flexed elbow

• B supracondylar

• C transcondylar

• D intercondylar

• E condylar

• F articular

• G epicondylar

Olecranon fractures

• Fall onto flexed elbow or forceful contraction of triceps

Mayo classification

• I, II, and III - level of displacement

• A and B - non communited/ communited

Post reduction - dislocations

• Patient is numbed and the arm is manipulated to put the shoulder back into its socket

• Puts head of humerus back into glenoid fossa

Types of shoulder dislocations

Anterior or posterior dislocations

Anterior dislocation examples

• Classified based on where the humeral head moves to

  • Subcoracoid

  • Subglenoid

  • Sub clavicular

  • Intrathoracic - rare

  • Anterior medial and inferior

  • Anterior more common than posterior

Posterior dislocation - shoulder

• Less common, overuse injury

• On exam: adduction and internal rotation (sling position)

• Humeral head behind glenoid fossa

Hills-sachs lesion

• Common post-anterior dislocations

• Often the result of an anterior dislocation

• Caused by humeral head strikes inferior glenoid

• Divot seen on superior posterior lateral aspect of humeral head

Reverse hills-sachs lesion

• Occur after posterior dislocation

• Divot in anterior aspect of humeral head

Bankart lesion

Damage to inferior glenoid after anterior dislocation

Neck of humerus fracture

• Communuted - multiple fragments

• The humeral head is moving medially and superiorly

Scapula fracture

clavicle fracture

• Communuted distal one third of clavicle

• Clavicle moved superiorly and distal part moved inferiorly

Shoulder impingement

Compression of supraspinatus tendon, subacromial bursa and long head of biceps tendon

• Due to decreased space under the coraco-acromial arch

• Sub acromial spurs which can cause impingement particularly in older people

Rotator cuff tear/degeneration

• Humeral head moves superiorly due to:

  • Weakening of rotator cuff pull medially

  • Deltoid pull superiorly

Calcific tendonitis

• Deposits of calcium in tendons of rotator cuff

  • Pain and reduced ROM

  • Supraspinatus common

Osteoarthritis shoulder

Shoulder replacement

Pleural effusion can be seen as costophrenic angles are not sharp

• When laying on the effected side you can see the fluid pooling at the bottom of the image with pleural effusion

Bones and soft tissue

• Trace all the bones carefully (including the spine)

• Looking for:

  • Fractures

  • Radiolucent or radiopaque areas

  • Dislocations

  • Destructive lesions

• Assess for any unexpected soft tissue swelling

Airways/assessment of quality

• Assess the quality of the image overall from a technical point of view

• Assess the airways from the trachea down to the left and the right bronchus

• Ensure the trachea is straight with no narrow points

• The carina should never be wider than 100 degrees

Cardiac

• Assess the cardiac border and ensure it is not obstructed

• Assess the mediastinum, taking into account all structures that make up the mediastinum

• Ensure the cardiac position is sound

• Ensure the arch and upper mediastinum is not widened

Diaphragm

• Ensure the diaphragm has a smooth border

• The right hemidiaphragm is generally higher than the left due to the liver

• Look for gas under the diaphragm - common on the left side because that is where stomach is (gastric bubble)

• On right side is liver so shouldn’t be any air

Effusion/ extra thoracic

• Assess for any effusions by checking costophrenic angles

• Assess for any extra thoracic soft tissue issues/air where it shouldn’t be

Fields/fissures/foreign bodies

• Check symmetry

• Compare each zone for changes in density and volume

• Start at the apex and working inferior and ensure the edges of the lungs are consistent

• Evaluate the fissures for any unexpected changes in position

• Check position for all FB that include lines or previously inserted surgical clips/layers

• Good to see lung markings behind the heart

Iatrogenic devices

• An xray cannot determine that a device is in the right place. Only in the wrong place

• Clinical correlation is essential

• Nasogastric tubes etc - need other things to determine it is in correct place

what devices are seen

• Two clips holding two ECG lines

• Through the trachea is the ETT

• Metal wires in the chest which are sternal wires

• Tube down from jugular vein into heart - CVC, swan ganz catheter

extrarathoracic devices

• Breast implants

• Attachments

pleural devices

• Thoracostomy tube

• Pigtail catheter

Tracheal and oesophageal devices

• Nasogastric tube

• Endotracheal tube

• Tracheostomy tube

intravascular devices

• CVC

• PICC

Cardiac devices

• Pacemakers

• Cardiac prosthetic valve

Orthopaedic devices

• Sternal wiring

• vertebroplasty

• Can either go through the internal jugular vein into the heart or through the subclavian vein

• If near the elbow it is a PICC line

• Can also go through the femoral vein

Breast implants

• Saline silicone

• Many types

• Unilateral or bilateral

• Increased ST density

• May extend beyond boundaries of the chest wall

• May have well defined contours

• Have an increased soft tissue density

Artefacts on chest images

• Tubing and external ports

• Sheets, pillows, clothing

• ECG electrodes and leads

• External pacemaker-defibrillator

• Should be removed prior to imaging where possible

• Should be included with interpretation

Thoracostomy tube use

Used for drainage of the pleural space

• Air (pneumothorax)

• Fluid (pleural effusion)

• Pus (emphysema)

Thoracostomy tube structure

• Flexible plastic tube

• End and side holes

• Attached to receptacle/water trap

• Inserted under local antithesis

• Flexible tube

• Incision into a safe area of the thoracic cage

• Tube passed through hole into pleural space

• Stitched in

Thoracostomy tube complications

• Haemorrhage

• Infection

• Rupture of lung tissue, liver, spleen, diaphragm

• Re-expansion pulmonary oedema

Thoracostomy tube why image?

• Check position - radio-opaque stripe, tube within pleural cavity

• Look for complications - tip of tube not abutting the mediastinum, parenchyma or a fissure

Nasogastric (NG) tubes uses

• Feeding

• Drug administration

• Imaging (contrast)

• Aspiration of stomach contents

NG tubes structure

• Single lumen rubber tube

• Flaccid with guide wire insert for positioning

• Narrow/wide

NG tube insertion

• Usually inserted unguided

• Guidewire for manipulation

• Through nose (or mouth) down oesophagus, into stomach (or further)

• Taped down

NG tube complications

• Enters skull vault

• Misplacement eg. Coiled up in throat/bronchus/too short/long

• Rupture of pleura

NG tubes - why image

• Ideally, should see entry point and able to track all the way down:

  • Positioning/rotation

  • Exposure

  • Leave wire in

  • Narrow/wide bore

  • Guide wire

• Travels centrally down oesophagus

• Tip past level of diaphragm

• Aim is to have it be 10cm to the oesophageal junction

Endotracheal tube indications for

• Assisted ventilation

• Isolate trachea to permit control of airway

• Prevents gastric distension

• Direct route for suctioning

• Administrations via ETT

endotracheal tube evaluation

• Assessed on frontal chest radiograph

• The carina should be projected over t5-t7

• The desired position should be 5+/-2cm above the carina

• In children, the trachea is shorter and desired position is 1.5cm above carina

• When carina not visualised (due to technical factors) ideal position is the middle third of the trachea (T2-T4 level)

endotracheal tube issues

• Most common malposition: tip in right main bronchus

  • Overinflation f the right lung and collapse of the left lung

• Tube in larynx or pharynx

  • Damage vocal cords

  • Aspiration

Tracheostomy indications for

• Airway obstruction at or above the level of the larynx

• Resp failure requiring long term intubation

• Paralysis of muscles that affect swallowing or respiration

Tracheostomy evaluation

• Assessed on the frontal chest radiograph

• Tip half way between the stoma and the carina

  • Above t3

• Tip placement not affected by flexion or extension

• Width of tube above 2/3rd width of trachea

complications

• Subcutaneous emphysema

• Pneumomediastinum

• Pneumothorax

• Tracheal stenosis

Chest trauma CXR role

1. What is the circulatory status

2. What is the respiratory status

3. Is there a tension in the pneumothorax

4. Is there a pericardial tamponade

• Widened mediastinal/abnormal mediastinal contours important indicator of mediastinal haemorrhage

Injury to: in chest traumas

• Pleural manifestation of trauma

• Thoracic cage

• Aorta and great vessels

• Heart and pericardium

• Pulmonary parenchyma

• Chest xray is always the primary image taken in response to trauma

Pleural manifestations of trauma

• Pneumothorax

• Haemothorax/pleural effusion

• Hemopneumothorax

• Associated collapse/atelectasis

  • Passive relaxation/collapse - passive removal of alveolar air by simple pneumothorax, diaphragmatic dysfunction or hypoventilation

  • Compressive collapse - extrinsic intrathoracic compression by air, fluid, mass

• Multiple rib fractures, pneumothorax on the left side

• Intercostal tube draining 

• Trachea is pushed to the right

Pneumothorax

• Presence of gas (Air) in the pleural space

• Mechanism: injury to the lung, either by trauma or iatrogenic cause resulting in air leaking into the pleural space

Spine pneumothorax

• Deep sulcus sign - abnormally prominent/deep costophrenic angle

• Uneven lung density - affected lung may appear abnormally translucent

• Subcutaneous emphysema - associated with rib fractures

• Tube on right side - right sided pathology

• Rib fractures on right side

• Costophrenic angle is high and the edge goes too deep - pneumothorax

Haemothorax

• Presence of blood in the chest, term used to define pleural effusion due to accumulation of blood

• Mechanism

  • Injury to the lung from penetrating or blunt trauma

  • Can occur without trauma = spontaneous haemothorax (malignancy, vascular rupture etc.)

• Radiographic appearances

  • Similar to pleural effusion

• Step in the right pleural line

• Outside of the line is all white

• This means there is a rupture of the pleura where the blood is getting into the lungs

Pleural effusion

• Fluid collection in the space between the parietal and visceral pleural layers

• Often results in pulmonary oedema, often of cardiogenic or non cardiogenic, often bilateral

• Cardiogenic pulmonary oedema - result of L HF or mitral valve disease

• Non-cariogenic - renal failure, infection (pneumonia, TB), surgery, malignancies, RA, liver failure, and malnutrition

What type of fluid can accumulate in pleural space?

Transudate

Exudate

Pus

Blood

Chyle

Cholesterol

Urine

Transudate fluid in lungs

due to hydrostatic pressure changes in CHF, cirrhosis and hypoalbuminemia

Exudate fluid in lungs

 due to inflammation of pleura such as malignancy, rheumatoid arthritis etc.

Pus in the lungs

emphysema from infection

Blood in lungs

trauma

Chyle in the lungs

from rupture of thoracic duct

Urine in lungs

urinothorax in hydronephrosis

Radiographic appearances of pleural effusion

• Erect position = pleura fluid gravitates to the lowest part of the thorax

• Homogenous opacification, generally same density as cardiac shadow

• Loss of outline of diaphragm

• No visual pulmonary or bronchiole marking

• Concave upper border with highest level in axilla

• Initially fluid accumulates in posterior of lung then lateral costophrenic space

• As fluid collection grows in size, underlying lung decreases in size and retracts towards the hilum

• With larger effusion, there is a mediastinal shift to the other side

• Rib fractures with too high costophrenic angle - pooling fluid

• Pneumothorax

• Both of these result in hemopneumothorax

Thoracic cage injuries

• Rib fractures

• Flail chest

• Sternal fractures

Rib fractures

• Common

• Limited clinical significance

• Oblique rib projections

• Medicolegal refferals

CXR to include

• Pneumothorax

• Haemothorax

• Pneumohemothorax

• Increasing number of broken ribs leads to increased trauma = increased incidence of intrathoracic trauma

• Considerable force required to break ribs 1 2 and 3 - rare

• Mainly in the middle that rib fractures do

• Ribs 10, 11, 12 indicate possible liver, spleen, and kidney injury

• Non-addental injury - in paediatrics

Flail chest

• Traumatic costochondral segment separated from chest wall

• Fracture of two or more contiguous ribs in two or more places

• Classic paradoxical movement in relation to the rest of the chest wall

• High association with other injuries

Radiographic findings of flail chest

• Multiple rib fractures

• Costochondral separation may be demonstrated

• Pulmonary contusion/laceration

Sternal fractures

• Typically result of car accident

• Frequency increases with age

• Not demonstrated on PA or AP CXR

• Difficult to identify on a lateral CXR

• Require dedicated projections

• Simple sternal fracture is typically benign - wont cause intrathoracic trauma

• Indicates significance of chest trauma

• Associated with sudden deceleration of forces: aortic or great vessel injury

 

chronic chest pathologies

• Consolidation

• Pneumonia

• Pulmonary oedema

• Bronchiectasis

• Atelectasis

• Chronic obstructive pulmonary disease

• Subcutaneous emphysema

• Carcinoma/pulmonary metastasis

Consolidation

• Refers to the alveoli/bronchioles being filled with fluid or some other material (eg. Inflammatory cells, tissues)

consolidation causes

• infection = pneumonia

• Fluid = pulmonary oedema

consoliation symptoms

• SOB

• Cough

• Fever

• Fatigue

• Chest pain

consolidation on radiograph

• Opacification

• Loss of cardiac silhouette

consolidation

Pneumonia

• Infection within the lung causing an inflammatory response of the alveolar tissue

• Etiological

  • Viral, fungal, or aspiration

• Acquisition

  • Hospital or community-acquired

• Spread of infection

  • Bronchopneumonia, lobar pneumoni

pneumonia radiographically

• Opacification

• Patchy (isolated nodules) or confluent (merged)

pneumonia

Pulmonary oedema

• Abnormal accumulation of fluid in the lungs

• Cardiogenic (ie. CCF) and non cardiogenic - caused from the heart or not caused from the heart

•