Download Emergency Radiographs

Emergency Radiographs
Emergency Radiographs
 Immediate action needs to be taken
 If the condition is life threatening, treatment
should be immediately started based on
clinical signs/physical examination without
waiting for radiographic confirmation
 Tension pneumothorax
 Radiographs can be stressful to already
compromised patients
 Congestive heart failure
Case 1
• 9 month old MN Jack Russell Terrier
• Vomiting and gagging
Esophageal Foreign Body
Esophageal Foreign Body
• Most common locations
Caudal esophagus
Thoracic inlet
Heart base
Esophageal Foreign Body
Radiographic Signs
• Visualization of a FB in the region of the
esophagus
• Deviation of the hilus or trachea
Esophageal Foreign Body
Radiographic signs
– If complete obstruction, may see dilation of the
esophagus cranial to the FB.
– Aspiration pneumonia!!!
– +/- pneumomediastinum
Esophageal Foreign Body
Positive Contrast
• Only if the foreign body is not definitively
identified
– Filling defect
Esophageal Foreign Body
Positive Contrast
• Barium sulfate
– Avoid with esophageal foreign bodies
• Pyogranulomatous reaction within the
mediastinum if esophageal tear
• Can make endoscopy difficult
Esophageal Foreign Body
Positive Contrast
• Barium sulfate
– Aspiration can cause pneumonitis and granulomas
of interstitial tissues and lymph nodes
• Likely volume dependent
• Small amount of aspiration likely negligible
Esophageal Foreign Body
Positive Contrast
• Iodinated contrast
– Prefer over barium sulfate
– Adverse reactions not reported with leakage into
the mediastinum
– Can cause pulmonary edema if aspirated
• Volume dependent
• May be more severe with ionic compared to non-ionic
Esophageal Foreign Body
• If there is a clinical concern for an esophageal
FB, make sure to also radiograph the cervical
esophagus
Esophageal Foreign Body
• Patient had endoscopy and the foreign body
was pushed into the stomach
• Followed with surgery/gastrotomy
Case 2
• 5 yr old FS Chihuahua
• Vomiting
Small intestinal mechanical
obstruction
Small intestinal mechanical obstruction
Radiographic signs
• Distention of small intestines orad to the
obstruction
– Two populations/diameters of bowel
Small intestinal mechanical obstruction
Radiographic signs
• Ratio small intestinal diameter to height of L5
vertebral body
– SI/L5 ratio of 1.95 = 77% probability of obstruction
– SI/L5 ratio of 2.07 = 86% chance of obstruction
• However, the SI/L5 ratio was not associated
with increased accuracy for observers,
regardless of level of experience
Ciasca TC. Does measurement of small intestinal diameter increase diagnostic accuracy of
radiography in dogs with suspected intestinal obstruction? Veterinary Radiology and Ultrasound
2013;54:207-211.
Small intestinal mechanical obstruction
Radiographic signs
• Ratio of small intestinal diameter to height of
L5 vertebral body
0.4 cm
0.4 cm
1.1 cm
1.1 cm
1.1/0.4 = 2.75
Small intestinal mechanical obstruction
Radiographic signs
• Make sure to measure from serosal to serosal
margin, not just the gas filled lumen
Incorrect!
Correct!
Small intestinal mechanical obstruction
Radiographic signs
• Decreased serosal detail within the abdomen
– Effusion and/or peritonitis
Small intestinal mechanical obstruction
Radiographic signs
• The more distal the obstruction, the greater
number of distended segments
Small intestinal mechanical obstruction
Radiographic signs
• With progressive distension, the distended
segments can have a stacked appearance
Small intestinal mechanical obstruction
Radiographic signs
• Partial obstructions can be difficult
– Can see a gravel sign with a chronic partial obstruction
– Fluid can pass through however larger pieces cannot and
become dessicated
Thrall Textbook of Veterinary Radiology; sixth
edition
Small intestinal mechanical obstruction
Radiographic signs
• Pneumoperitoneum if ruptured
– Make sure to include the cranial abdomen
– Commonly accumulates between liver and
diaphragm
Small intestinal mechanical
obstruction
• Right AND left lateral projections
– Redistributes gas and fluid in the stomach and
intestines
Left lateral
Right lateral
Small intestinal mechanical
obstruction
• Not always due to foreign body
– Intestinal masses (especially in older patients
without history of foreign body ingestion)
• Ultrasound may be helpful if presence of a mass will
preclude surgery
– Intussusception, adhesions, extraluminal masses
Functional ileus
• Functional ileus results in decreased motility due to a
neurologic or muscular dysfunction
• Distention of small intestine (usually not as severe as an
obstruction)
• Can be seen with enteritis (HGE and parvo), dysautonomia,
certain drugs
• Usually generalized dilation of bowel in contrast to two
populations of bowel
• A distal small intestinal mechanical obstruction can mimic
• Clinical signs/signalment
Case 3
• 9 wk old MI Golden Retriever
• Vomiting for 2 days and diarrhea for 2 weeks
• Lethargic
Findings
• A few intestinal segments are gas distended
• Not all are in the plane of the colon
Pneumocolon
Pneumocolon
Intussusception
Intussusception
• One intestinal segment (intussesceptum)
telescopes/invaginates into the lumen of the
adjacent segment (intussuscipiens).
– Difference in motility between adjacent segments
– Ileocolic or cecocolic junction most common location
Intussusception
Radiographic signs
• Intestinal distention depends on location and
severity of obstruction
• Obstruction may be transient
• If causing a distal obstruction, can get diffuse
small intestinal distention
• Can sometimes see intussusception if there is
enough surrounding gas
• Can be a difficult diagnosis
Intussusception
• Ultrasound helpful!
– Transverse view
• Bull’s-eye, concentric rings like onion
– Mesenteric fat can be pulled into lumen of
intussuscipiens
Intussusception
• Ultrasound helpful!
– Longitudinal view
• Linear layers of intestinal wall
Case 4
• 2 yr MN DSH
• vomiting
Linear foreign body
Linear foreign body
Radiographic Signs
• Plication of small intestines
– Proximal portion of the linear foreign body becomes
stuck at a fixed location and rest extends into the small
intestine
– Most commonly pylorus in dogs and base of tongue in
cats
– Peristalsis of small intestines causes the bowel to ride
up the foreign body
Linear foreign body
Radiographic Signs
• Plication of small intestines
Linear foreign body
Radiographic Signs
• Plication of small intestines
Linear foreign body
Radiographic Signs
• Plication of small intestines
– Fragmented gas pattern
– Comma shaped/angular gas bubbles instead of
normal round gas bubbles
Linear foreign body
Radiographic Signs
• Plication of small intestines
Linear foreign body
Radiographic Signs
• Typically DOES NOT cause small intestinal
distention
• Partial mechanical obstruction
Linear foreign body
• Can be a challenging diagnosis
• Ultrasound can be helpful if radiographs are
not definitive
– Undulating mucosa surrounding a hyperechoic
central line
Case 5
• 6 yr old MN Labrador
• Retching/gagging
Gastric dilation and volvulus
(GDV)
Gastric dilation and volvulus
• The stomach is freely movable around its point of
attachment to the diaphragm
• It is attached by the gastrophrenic ligament at the
esophageal hiatus and by the gastrohepatic ligament
which connects the lesser curvature and pylorus to
the hilus of the liver.
• The gastroduodenal and gastrosplenic ligaments do
not limit rotation except for the influence of the
splenic vessels.
• The main features that prevent undue movement of
the stomach are the other abdominal organs and the
abdominal wall
Gastric dilation and volvulus
• The stomach usually rotates in a clockwise
direction (viewing the patient from the caudal
direction)
http://drstephenbirchard.blogspot.com/2013/09/gastric-dilatationvolvulus-which-dogs_2.html
Gastric dilation and volvulus
• In a normal dog, the pylorus is within the right
abdomen and fundus is within the left abdomen
• With a GDV, the pylorus usually deviates
craniodorsally and to the left of midline
pylorus
fundus
Gastric dilation and volvulus
• Right lateral most diagnostic
• DV if patient is stable enough
– Concurrent splenic torsion
– Evaluate if pylorus is to the right or left of midline
Gastric dilation and volvulus
Radiographic signs
• Large gas and fluid (more gas than fluid)
distended stomach
Gastric dilation and volvulus
Radiographic signs
• Location of the pylorus near or to the left of midline
and dorsally
• DV helpful if patient stable enough
Gastric dilation and volvulus
Radiographic signs
• Soft tissue line across the distended stomach separating the
gas containing sections of the stomach into compartments
– Stomach fold projects into the lumen and is outline by gas
– Runs approximately in craniocaudal direction
Gastric dilation and volvulus
Radiographic signs
•
+/- Splenomegaly
– impaired circulation
•
•
Variable location of the body of the spleen
DV helpful
Gastric dilation and volvulus
Radiographic signs
• Thin gastric wall
• Gas sometimes seen in the wall (pneumatosis)
– Theories include gastric wall necrosis, prior
trocharization, gas under pressure forced into
submucosa, increased mucosal permeability.
– Radiographic evidence has low sensitivity for gastric
necrosis (14.1%) but high specificity (92.7%).
– Not reliable indicator for gastric resection during
surgery.
Fischetti AJ, Pneumatosis in canine gastric dilatation-volvulus syndrome. Veterinary Radiology
and Ultrasound. 2004;45:205-209.
Gastric dilation and volvulus
Radiographic signs
• Hypovolemia, with small caudal vena cava and
cardiac silhouette
Thrall Textbook of Veterinary Radiology;
sixth edition
Gastric dilation and volvulus
Radiographic signs
• Caudal esophageal distention
– The rotation of the stomach twists the terminal
esophagus, causing obstruction that prevents
eructation and vomition of gastric contents.
Case 6
• 12 yr old Akita
• Painful abdomen
Case 6
Case 6
Gastric dilation
Gastric dilation
• Acute gaseous distension of the stomach may be
secondary to aerophagia or gastric atony/ileus
– Pain, drugs, panting, etc.
• Radiographic determination of the location of the
pylorus is the key differentiating feature between
dilation and volvulus.
– Look for location of spleen
• Typically not a surgical emergency, but evaluate
clinical signs
Gastric dilation
• Gas filled
– Aerophagia
– Gastric atony
• Gastritis
• Medications (e.g. opioids)
• Fluid filled
– Gastric atony
– Pyloric outflow obstruction
• Heterogeneous gas and soft tissue
– Gastric atony
– Food bloat
– Pyloric outflow obstruction (sometimes gravel sign)
Case 7
• 12 yr old Rhodesian Ridgeback
• Gagging/retching
360o gastric dilation and volvulus
• RARE!!!
• Similar to severe gastric dilation
– Pylorus and fundus seem to be in appropriate
location
360o gastric dilation and volvulus
• Spleen not in normal location…
• Poor clinical status of patient
• DV helpful!
Case 8
• 8 yr old Golden Retriever
• Tachypnea
Pneumothorax
Pneumothorax
• Due to air accumulation within the pleural
space
• Due to air leaking from
– penetrating wound - OPEN
– Airways - CLOSED
– Pneumomediastinum - CLOSED
• A pneumomediastinum can cause a
pneumothorax however a pneumothorax
cannot cause a pneumomediastinum
Pneumothorax
• Air leaking from airways
– Bulla/bleb
– Rupture of a cavitary lung mass
Pneumothorax
Radiographic signs
• Usually bilateral due to incomplete
fenestration of the mediastinum in dogs and
cats
• However can be unilateral if the mediastinal
fenestrations become closed due to pleural pathology
(e.g. fibrin/adhesions)
Pneumothorax
• Unilateral pneumothorax
Pneumothorax
Radiographic signs
• Retraction of lung from the body wall
– Severity depends on amount of pleural gas/pressure
• Caudal displacement of diaphragm depending on severity
Pneumothorax
Radiographic signs
• Pulmonary markings/vessels do not extend to
the body wall
Pneumothorax
Radiographic Signs
• Do not be fooled by skin folds
• Look for pulmonary markings/vessels over the fold
• Margin of the fold extends beyond margins of thorax
• No air between lung and diaphragm
Pneumothorax
Radiographic Signs
• Do not be fooled by skin folds
• Look for pulmonary markings/vessels over the fold
• Margin of the fold extends beyond margins of thorax
• No air between lung and diaphragm
Pneumothorax
Radiographic Signs
• Separation of the cardiac silhouette from the
sternum on lateral
– Do not confuse with ventral mediastinal fat
– Look for lack of pulmonary markings
Pneumothorax
Radiographic Signs
• Separation of the cardiac silhouette from the
sternum
• Not really elevated
• Heart is displaced laterally into the dependent thorax
due to underinflation of the lung
Thrall Textbook of Veterinary Radiology; sixth
edition
Pneumothorax
Radiographic Signs
• Increased opacity/unstructured interstitial
pattern in lungs due to secondary atelectasis
Case 9
• 5 yr old MN DMH
• Severe tachypnea
Tension Pneumothorax
Tension pneumothorax
• Pleural pressure exceeds atomspheric
pressure during both phases of respiration
– Check valve mechanism at the origin
• Air enters during inspiration and does not
escape during expiration
• Pleural pressure rises, compromising
ventilation and circulation
• Requires IMMEDIATE thoracocentesis and
ultimately chest tubes
Tension pneumothorax
• Treat the patient first based on physical
examination findings
– If air spontaneously fills the syringe during
thoracocentesis, a tension pneumothorax is
confirmed.
Tension pneumothorax
Radiographic Signs
• SEVERE retraction of the lungs from the body
wall
• May be so severe that it does not resemble the shape
of the lung
Tension pneumothorax
Radiographic Signs
• Contralateral mediastinal shift if unilateral
– In a regular pneumothorax the shift is toward the
most collapsed side
Tension pneumothorax
Radiographic Signs
• +/- caudal displacement of the diaphragm
Case 10
• 10 yr old mixed breed dog
• Difficulty breathing
Left sided congestive heart failure
Left Sided Congestive Heart Failure
Radiographic signs
• Perihilar and caudodorsal pulmonary edema
– The high diastolic pressures in the left ventricle
and/or left atrium “backs up” into the pulmonary
veins and capillaries, causing transudation of fluid
from the capillaries into the pulmonary
interstitium and alveoli (pulmonary edema).
• Can have a more patchy distribution in cats
and some dogs
Left Sided Congestive Heart Failure
Radiographic signs
• Pulmonary edema
Left Sided Congestive Heart Failure
Radiographic signs
• Venous distention
Enlarged cranial lobar veins
Normal thorax
Left Sided Congestive Heart Failure
Radiographic signs
• Increased height of the cardiac silhouette with dorsal
displacement of the trachea
– Left ventricular enlargement
Left ventricular enlargement
Normal thorax
Left Sided Congestive Heart Failure
Radiographic signs
• Straightening of the caudal cardiac waist
– Left atrial enlargement
Left ventricular enlargement
Normal thorax
Left Sided Congestive Heart Failure
Radiographic signs
• Straightening of the caudal cardiac waist
– Left atrial enlargement
Left ventricular enlargement
Normal thorax
Left Sided Congestive Heart Failure
Radiographic signs
• Left atrial enlargement
Left Sided Congestive Heart Failure
Radiographic signs
• +/- left auricular enlargement
Left Sided Congestive Heart Failure
• Cats can get pleural effusion with left sided congestive heart
failure
– Increased pulmonary vein pressure as a result of left heart
failure can lead to the formation of pleural effusion
because visceral pleural veins (the veins on the surface of
the lung) also drain into the pulmonary veins in cats and
dogs.
• Pleural effusion does not happen in left sided heart failure
with dogs. More concern for right sided heart failure.
Left sided congestive heart failure
vs bronchopneumonia
• Bronchopneumonia typically has a ventral
distribution of disease, not perihilar or
caudodorsal
Left sided congestive heart failure
vs bronchopneumonia
• Bronchopneumonia typically has a ventral
distribution of disease, not perihilar or
caudodorsal
Left sided congestive heart failure
vs bronchopneumonia
• Evaluate size of the cardiac silouette and veins
Left sided congestive heart failure
vs bronchopneumonia
• If in doubt, treat with lasix and look for
response
Case 11
• 3 yr old Chihuahua
• 3 day history of ptyalism, decreased appetite,
and abdominal pain
Lung lobe torsion
Lung lobe torsion
• Lung lobe rotates along its long axis
• Twisting of the bronchus and vessels at the level of
the hilus
• Depending on the severity of the torsion, the veins
are compressed, impeding venous return
– Less compressible arteries continue to supply blood 
venous congestion and sequestered blood in the lobe
– Fluid and blood enter airways and also leak from the
surface  pleural effusion
Lung lobe torsion
– Can be difficult to diagnose with radiographs
– CT may be more sensitive however patient may
not have enough time
• If the lobe is torsing intermittently, may not see it on CT
– Suspicion increased in patients with an initial nonhemorrhagic effusion that has suddenly changed
to a hemorrhagic effusion combined with a
decline in clinical status
Lung lobe torsion
Typical radiographic signs
• Alveolar pattern in affected lung lobe
• Mass effect
• Pleural effusion
– Can mask the affected lung lobe
– Repeat radiographs after thoracocentesis
Lung lobe torsion
Typical radiographic signs
• Can progress into a vesicular pattern
– Due to abscessation
Lung lobe torsion
Typical radiographic signs
• Sometimes can see blunted termination of
bronchus
• Bronchus or vessels coursing in an abnormal
direction
• CT may allow visualization of torsed bronchus,
however patient may need to go to surgery
based on radiographic suspicion and clinical
signs
Lung lobe torsion
• Differentials
– Abscess
• Causes
– If effusion was present prior due to other disease, may predispose
patient to developing a lung lobe torsion – effusion displaces lung
lobes
– Pugs predisposed?
– Less common in cats?
• Right middle lung lobe most affected, left cranial next
common affected
– Right middle lung lobe most mobile and has a long , narrow shape
• Swelling of lung lobe and rapid adhesion formation do not
permit the lung to reposition itself
Questions???