pathology mod 3

what is a small bowel obstruction?

obstruction to passage of chyme (any materials, food, liquids) in the small bowel due to various causes such as adhesions, hernias, or tumors, leading to symptoms like abdominal pain, bloating, and vomiting.

what percentage of small bowel obstructions are caused by adhesions caused by previous surgery or peritonitis

75%

what is the second most common cause for a small bowel obstruction

hernia

other than adhesions and hernias what else can cause SBO

• tumours

• interceptions (piece of the bowel loop gets looped around itself)

what does a SBO look like radiographically

• stacked coin/ step ladder appearance

• distended/ dilated loops of SB containing gas & air fluid with decreased or absent bowel sounds

do we use barium or iodinated contrast with a SBO

Iodinated contrast is preferred because barium can worsen peritonitis

• but it is up the rad

CT SBO indicates what?

strangulation of bowel loops

• questionable blood supply

SBO target sign is caused by

the enhancing mucosa and muscularis with edematous submucosa in between

• can be caused by herniation of bowel

what is adynamic ileus

absent/failure of peristalsis through an unobstructed small and large bowel

when does adynamic ileus frequently occur?

post abdominal surgery- “postoperative ileus”

• usually resolves itself within 3 days

• closely monitored

• pt can’t leave until they have passed gas

what are some other causes of adynamic ileus

• peritonitis

• medication (narcotics)

what are some signs and symptoms of adynamic ileus

• abdominal distention

• vomiting

• cramping

what does adynamic ileus look like radiographically

• retain large amounts of gas and fluid in dilated small and large bowel (depending where ileus is)

• uniform dilation

• no apparent site of obstruction

what are the 2 major types of adynamic ileus

• localized ileus

• colonic ileus

what is localized ileus

temporary and limited form of adynamic ileus affecting only a short segment of the small or large intestine. It's often seen as a reaction to inflammation or irritation in a nearby area within the abdomen

• an isolated SB or LB loop

what is colonic ileus

the most common type

• adynamic ileus affecting the colon (large intestine)- all over ileus. This means a decrease or absence of motility in the colon without a mechanical obstruction

• LB with increased gas

• often follows surgery- similar to mechanical obstruction on x-ray

• need a barium enema to rule out distal lesion or a CT

if you have a hole in your stomach where does the gas/ air go?

up

• perforation allows for air to escape into abdominal cavity

what is pneumoperitoneum

refers to the presence of free air or gas within the peritoneal cavity, which is the space in the abdomen that contains the internal organs. Normally, there is very little to no free air in this space

• air rises to the highest level

what is pneumoperitoneum caused by

In an adult: rupture/perforation

In neonatal:

• meconium ileus

• intestinal atresia (intestines don’t attach @ certain points)

• intubation/ mechanical ventilation (can perforate through)

• rectal thermometer/ enema (can perforate through)

what is the best position to x-ray a patient with pneumoperitoneum

upright

• patient upright for about 10 mins is best

what xrays are done for pneumoperitoneum

• supine

• x-table laterals or decubs (left side, stomach down)

we image to see fluid levels

what is the falciform ligament sign and when can it be seen

• directly related to and indicative of pneumoperitoneum

• supine pt.

• When free air accumulates in the abdominal cavity, it rises to the highest points when the patient is supine. Because the falciform ligament is a vertical structure extending from the anterior abdominal wall to the liver, free air can accumulate on either side of it, outlining its course and making it visible on imaging

what is the double wall sign and when can it be seen

• also known as Rigler's sign, is a radiographic sign of pneumoperitoneum 

• seen on an abdominal radiograph (supine) when air outlines both the inner (luminal) and outer (serosal) surfaces of the bowel wall

• when free air is present in the peritoneal cavity, it can accumulate outside the bowel wall, creating a visual separation and highlighting both sides of the intestinal wall as a thin, radiopaque line bordered by lucent air on either side

what is ascites

excess amount of fluid in peritoneal cavity

causes of ascites

• liver diseases

• cardiac diseases

• peritoneal diseases

• pancreas

• kidney

• lymphatic system

what does ascites look like radiographically

supine- bowel gas centrally and none peripherally

• consider gas is floating on a lake of fluid

for ascites, what technical adjustments would be made

patho textbook: increase kV

McQ: increase 30-50% mAs OR 5-8 kV

why is it not safe to send patient home with SB obstruction?

perforation can occur which leads to pneumoperitoneum

what’s important with chest pathologies

• subtle changes- density, pulmonary/vascular markings

• technical factors (adequate density) and positioning are critical and must be consistent between cases so they can compare

• consistent phase of respiration (usually inspiration)

what do you look for in chest x-rays

• trace the diaphragm

• size and shape of the heart

• mediastinum

• thymus

• CTR

• look at the integrity of the ribs, clavicle, spine, soft tissues

• lungs

  • blood vessels (end-on)

  • interlobar fissures (only if tangential to beam)

  • pectoral muscles

  • beasts and nipple

hereditary

passed down through genes

congenital

born with

what is cystic fibrosis

a hereditary disorder characterized by lung congestion and infection and malabsorption of nutrients by the pancreas. A secretion of thick mucous by ALL endocrine glands

what does cystic fibrosis look like

• thick lung markings, hyperinflation of lungs

• pancreatic duct filled with mucous that blocks the pancreatic duct and structures (not seen on an CXR) that can lead to pneumothorax

what are some treatments for cystic fibrosis

• prophylactic antibiotics (preventative)

• chest physiotherapy (tapping, vibration vest, etc, used to try and keep fluid moving)

• improved airflow

*Future- gene therapy

what is another name for hyaline membrane disease

IRDS

idiopathic/infantile respiratory syndrome

what is IRDS/hyaline membrane disease caused by

it is distress in newborns caused within 6 hours of birth; caused by a lack of surfactant, a substance that helps the lungs inflate and prevents the air sacs from collapsing.

• surfactant is in the alveoli which help keep the lungs inflated

• the air sacs in the lungs collapse, and a glassy, protein-rich substance called a hyaline membrane forms, making it difficult to breathe

who are the babies who are more likely to get IRDS/hyaline membrane disease

premature infants:

• C- section

• diabetic mom

what does IDRS/hyaline membrane disease look like radiographically

• granular parenchyma- grainy appearance to chest tissues

• under aeration- lungs don’t have black air filled look

• air bronchogram sign- grainy grey chest, outline of brachial tree, not alot of air

whats the treatment for hyaline membrane disease

• artificial surfactant

• ventilators

what is the importance of history

Many pathologies look similar so knowing symptoms would be helpful because for example pneumonia and cancer would look similar radiographically but their symptoms would be very different and could help you to make the proper diagnosis

whats a pneumothorax

air in pleural cavity= partial or complete collapse

• outside air rushes in due to disruption of chest wall and parietal pleura; air from outside or air in lung getting into lung causing it to collapse

what are some causes of pneumothorax

1. Spontaneous: young healthy adult

• common cause: ruptured subpleural bulla

2. iatropathic (healthcare related)

   • complication of lung biopsy

3. trauma- blunt trauma

atelectasis

reduced lung volume in some part of the chest/lung

• partial collapse

• commonly results from bronchial obstruction

• see horizontal linear opaque streaks

whats are examples of atelectasis

• neoplasm

• foregin bodies

• muscus plug

a pneumothorax is essentially a big _________

atelectasis

pneuomothorax distribution; what do you see when supine vs when erect

supine: space anteriorly

erect: space posteirorly

what does pneumothorax look like radiographically

• hyperlucent

  • darker appearance

• no pulmonary markings

• visceral pleural line (line edge)

• upright is the most beneficial for small pneumos; if can’t, do lateral decubitus

• inspiration unless otherwise requested

• if done on expiration, take AEC off and increase technique 30%

whats a tension pneuomothorax

there is an increase in pressure build up, more air is coming into lung with every breathe increase air which increases pressure, pushing along midline

what can a malpositioned ET tube cause

collapse of lung, if it goes into a bronchi

• more likely to be the right one because it is more vertical, wider and shorter

what is mediastinal emphysema (pneumomediastinum)

air in the mediastinum; between the lungs

• air escapes from the lungs, airways, or esophagus and enters the mediastinum

how do you get mediastinal emphysema (pneumomediastinum)

1. spontaneous- pressure, vomiting, severe coughing or straining

2. trauma- blunt such as gunshot or stabbing

3. perforation- intrument going through esophagus or airway

what is the first radiographic sign of mediastinal emphysema (pneumomediastinum)

lateral displacement of mediastinal edge

what is subcutaneous emphysema (non-pulmonary)

air from the mediastinum, or sometimes directly from a lung or airway (can happen from blunt trauma or perforation), travels under the skin, into the tissues of the chest wall. This can cause swelling and a crackling sensation when the skin is touched (crepitus/crepitation)

whats a radiographic sign of subcutaneous semphysema (non-pulmonary)

radiolucent streaks

whats a pleural effusion

fluid in pleural space

what are some causes of pleural effusion

• congestive heart failure (CHF)

• pulmonary embolism (PE)

• infection

• neoplasm

• pancreatitis

what can you see on an x-ray of someone with pleural effusion

• blunting of costophrenic angles which indicates fluid

• < 5ml of fluid seen in lateral decubitus

• small pleural effusion- lateral view posteriorly (400 ml may not produce blunting on PA)

• use horizontal CR always when looking for fluid

what is thoracentesis

a type of treatment used to drain fluid out of pleural cavity by sticking a needle into the pleural space

emphysema

pus or infected liquid

hemothorax

blood in pleural cavity

hydrothorax

water in pleural cavity

hemohydrothorax

blood and water in pleural cavity

what is croup (laryngotracheobronchitis)

• viral- swelling subglottic trachea

• barking cough or stridor; high pitched squeaky noise as they breathe

whats the sign for croup

chruch steeple sign

• do an AP soft tissue neck

whats the treatment for croup

• steroids

• moisture

• cold air

epiglottitis

acute infection of epiglottic tissue causing swelling

• this is an emergency

what projection and exam do we do for epiglottitis

lateral view of soft tissue neck

what do you not want to do with a patient who has epigottitis

• don’t put them supine

• don’t move their head

what is pneumonia

inflammation caused by infection

what are the causes for pneumonia and which is the most common

• bacteria (most common)

• viruses (most common)

• fungi

what is lobar pneumonia/ alveolar/ air space

entire lung is infected, exudate (fluid/pus) replaces the air in the alveoli

• the affected lobe will appear solid/white/ radiopaque

• its usually unilateral

what is bronchopneumonia

bacterial staphylococcal infection that originates in bronchi and spreads to alveoli

• small patches of consolidation/ often bilateral

what is interstitial pneumonia/ viral

caused by viral or mycoplasmal infection

• involves wall and lining of alveoli

• multiple small nodular densities

• untreated results in cyst-like spaces and fibrotic walls

what is aspiration pneumonia

caused by aspirating food or fluid in the lungs

• multiple alveolar densities bilaterally

• posterior segments of upper and lower lobes (common)- especially when bedridden

what are treatments for aspirating pneumonia

early diagnosis and antibiotics

pneumocystic (carinii) pneumonia

brought on by a fungus that is spread through the air

• comes on suddenly and severe

• HIV+

• perihilar infiltrate; spreads to periphery; opacity is closer to hilum

whats a lung abscess

• necrotic area with purulent (pus type) material

• encapsulated, keeping fluid inside

• aspiration (most common), obstruction, pneumonia

• infected material via blood go to brain and develops abscess

what is tuberculosis (TB)

infectious disease caused by a bacterium called Mycobacterium tuberculosis.

• early is asymptomatic (skin test or CXR- testing for previous TB not curent)

• It primarily affects the lungs but can also involve other parts of the body, such as the lymph nodes, bones, and brain (GI, genitourinary, skeletal)

how is TB spread

TB is spread through the air when a person with active TB disease coughs, sneezes, or speaks, releasing tiny droplets containing the bacteria. Inhaled from dried sputum that has turned to dust

where is TB common and what is the best view for it

• apical regions

• lordotic view of chest

what are symptoms of TB

cough and dyspnea

what is evident on a CXR of someone with TB

scarring fibrous tissue and necrosis

primary TB

can develop at any age

what does primary TB look like on an x-ray

• lobar/ segmental air space consolidation

• enlargement hilar or mediastinal lymph nodes

• pleural effusion (common in adults)

miliary TB

• spread via blood

• bilateral small granulomas distributed uniformly (both lungs)

secondary TB (reacativation)

• previously dormant tubercle becomes active

• heals slowly

• extensive fibrosis and scarring, especially upper lobes

tuberculoma TB

• obvious nodule containing viable bacilli that can develop in primary or secondary disease

• periphery and upper lobes

what is SARS

severe acute respiratory syndrome

• viral

• droplet (~8000 cases worldwide)

• mild respiratory symptoms progress to pneumonia (not contagious until symptomatic)

• asia to north america in 2003

what is COPD

chronic obstructive pulmonary disease

• which leads to ineffective gas exchange and makes breathing difficult

COPD is an umbrella term, what diseases fall under COPD

• asthma

• bronchiectasis

• bronchitis

• emphysema

what are some common radiographic appearances of COPD

• hyperinflation of lungs

• flattened diaphragm

• increased retrosternal air space

what is retrosternal airspace

lucency between posterior sternum and anterior ascending aorta on lateral CXR

• normally < 2.5cm wide

what is emphysema

• destruction of alveolar walls

• AP diameter of chest increase because air is trapped (barrel shaped chest)

what is chronic bronchitis

chronic inflammation of bronchis

what does chronic bronchitis look like radiographically

• increased bronchovascular markings, especially lower

• narrowing of airways

• 90% associated with cigarette smoking

what is asthma

• spasm and narrowing

• decreased airflow

• obstruction

• usually a response to a stimuli such as an allergen or exercise

what are some common asthma triggers

• pollen

• dust mites

• pet dander

• mold

• exercise

what is bronchiectasis

permanent abnormal dialation of 1 or more large bronchi due to destruction of bronchial walls

• chronic productive cough, hemoptysis (coughing up blood)

• fibrous and interstitial changes in lung

what is sarcoidosis

multisystem granulomatous disease- creates granules as structure is formed during inflammation, like a collection of immune cells

• bilateral hilar lymph node involvement

• unknown cause

• common in young adults

• destruction of fine bony trabeculation in hands and feet