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1 Peter V. Scrivani, DVM Assistant Professor, Department of Clinical Sciences Pulmonary Imaging Outline Pulmonary anatomy Selecting the imaging examination Principles of radiographic interpretation The incompletely expanded lung The fully expanded lung Summary Break Pulmonary Anatomy Pulmonary Anatomy 2 lungs Left Right 2 “lung fields” Cranioventral Caudodorsal Dog: Left lung Gross Anatomy 6 lung lobes Right cranial Right middle Right caudal Accessory Left caudal Left cranial Cranial part Caudal part Bronchopulmonary segments 226111 Gross Anatomy Trachea Principal bronchi Lobar bronchi Segmental bronchi » Bronchi Bronchioles 187515 LLAT RLAT PULMONARY IMAGING: GETTING THE MOST INFORMATION FROM THORACIC RADIOGRAPHS Peter Scrivani, DVM, DACVR Cornell University College of Veterinary Medicine, Ithaca, NY

Principles of radiographic interpretation Pulmonary Imaging · PDF file · 2017-09-07– Shallow breathing – Gravity dependent ... – Neonatal respiratory distress syndrome

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Page 1: Principles of radiographic interpretation Pulmonary Imaging · PDF file · 2017-09-07– Shallow breathing – Gravity dependent ... – Neonatal respiratory distress syndrome

1

Peter V. Scrivani, DVMAssistant Professor, Department of Clinical Sciences

Pulmonary Imaging

Outline

• Pulmonary anatomy• Selecting the imaging examination• Principles of radiographic interpretation• The incompletely expanded lung• The fully expanded lung• Summary

Break

Pulmonary Anatomy

Pulmonary Anatomy

• 2 lungs– Left– Right

• 2 “lung fields”– Cranioventral– Caudodorsal

Dog: Left lung

Gross Anatomy

• 6 lung lobes– Right cranial– Right middle– Right caudal– Accessory– Left caudal– Left cranial

• Cranial part• Caudal part

• Bronchopulmonary segments

226111

Gross Anatomy

• Trachea– Principal bronchi

• Lobar bronchi– Segmental bronchi

» Bronchi

• Bronchioles

187515 LLAT RLAT

PULMONARY IMAGING: GETTING THE MOST INFORMATION FROM THORACIC RADIOGRAPHS

Peter Scrivani, DVM, DACVRCornell University College of Veterinary Medicine, Ithaca, NY

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Gross Anatomy

Artery, bronchus, vein

Artery, Bronchus, Vein

Veterinary Radiology & Ultrasonography 2012;53(1):1-10.

Histologic Anatomy

Veterinary Radiology & Ultrasonography 2012;53(1):1-10.

Histologic Anatomy

Conducting Zone Respiratory Zone

Radiographic Localization of Lung Disease

• Bronchovascular bundle (conducting zone)

• Pulmonary parenchyma (respiratory zone)

• Pulmonary blood vessels

Gross & Histologic Anatomy

• Lung– Lobe

• Bronchopulmonary segment–Secondary pulmonary lobule

»Pulmonary acinus• Primary pulmonary lobule

• Alveolus

• Wall

• Space

(interstitial pattern)

(alveolar pattern)

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Gross & Histologic Anatomy

• Lung– Lobe

• Bronchopulmonary segment–Secondary pulmonary lobule

»Pulmonary acinus• Primary pulmonary lobule

• Alveolus

• Wall

• Space

Imaging limit

(interstitial pattern)

(alveolar pattern)

Gross & Histologic Anatomy

• Lung– Lobe

• Bronchopulmonary segment–Secondary pulmonary lobule

»Pulmonary acinus• Primary pulmonary lobule

• Alveolus

• Wall

• Space

(interstitial pattern)

(alveolar pattern)

Imaging limit

Anatomic Organization of the Lung

Computed tomography of the lung, A pattern approach, 2007, Springer

Anatomic Organization of the Lung

Computed tomography of the lung, A pattern approach, 2007, Springer

Anatomic Organization of the Lung

Computed tomography of the lung, A pattern approach, 2007, Springer

Pulmonary InterstitiumConnective Tissue

Computed tomography of the lung, A pattern approach, 2007, Springer

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Pulmonary InterstitiumConnective Tissue

1. Subpleural space, bronchopulmonary segments,secondary pulmonary lobules, & pulmonary acini

2. Originate at hilum, surrounds bronchovascularstructures & alveoli

3. Between the alveoli and capillaries (alveolar wall)

Computed tomography of the lung, A pattern approach, 2007, Springer

Pulmonary InterstitiumConnective Tissue

1. Subpleural space, bronchopulmonary segments,secondary pulmonary lobules, & pulmonary acini

2. Originate at hilum, surrounds bronchovascularstructures & alveoli

3. Between the alveoli and capillaries (alveolar wall)

Computed tomography of the lung, A pattern approach, 2007, Springer

Bovine & Canine Lungs

Selecting the Examination

Selecting the Examination

• Orthogonal-view thoracic radiography– RLAT and DV– LLAT and VD– Other combinations

• 1-view thoracic radiography• 3-view thoracic radiography• Thoracic CT

In small-animals, see lung lesions best in the “up” lungOther lesions best when placed close to the detector

Cardiac cases

Respiratory cases

“Up” lung

195681

L

R

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LLAT & RLAT

221686

DV & VD

191703

DV & VD

192308 Pleural fluid

Principles of Interpretation

Principles of Radiographic Interpretation

• Assuming proper– Examination– Positioning – Exposure – No superimposition

of collar, wet hair, etc.

Breed Conformation

227238—Boxer 203368—Chihuahua

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Age-related Changes & Body Condition

206192

Principles of Radiographic Interpretation

• Classic pattern approach– Interstitial pattern– Alveolar pattern– Bronchial pattern– Vascular pattern– Mixed pattern

Principles of Radiographic Interpretation

• Pulmonary patterns are a combination of signs– Degree of lung expansion– The opacity of the lung– Appearance of increased opacity– Macroscopic distribution of altered opacity– Additional signs

Principles of Radiographic Interpretation

• Pulmonary patterns are a combination of signs– Degree of lung expansion

• Reduced, normal, or increased– The opacity of the lung

• Increased or decreased– Appearance of increased opacity

• Alveolar, interstitial, bronchial, vascular– Macroscopic distribution of altered opacity

• Cranioventral, diffuse, lobar, focal, etc– Additional signs

Principles of Radiographic Interpretation

• Pulmonary patterns are a combination of signs– Degree of lung expansion

• Reduced, normal, or increased– The opacity of the lung

• Increased or decreased– Appearance of increased opacity

• Alveolar, interstitial, bronchial, vascular– Macroscopic distribution of altered opacity

• Cranioventral, diffuse, lobar, focal, etc– Additional signs

Incomplete Lung Expansion

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Incomplete Lung Expansion

• Often considered as onlya technical complication– Obscure pathology– Spurious pathology

• Cardiomegaly• Increased lung opacity

224972

Exhalation

Incomplete Lung Expansion

224972

Exhalation Inhalation

Textbook of Veterinary Diagnostic Radiology, 3rd Ed.

Incomplete Lung Expansion

• Commonly due to normal exhalation• Can be a component of the disease process

– Reduced or absent gas exchange– Clue to the underlying pathology

Signs of Incomplete Lung Expansion

• Decreased lung size• Increased opacity• Lobar sign • Crowding of ribs • Air bronchogram sign • Positive silhouette sign • Poorly defined margins of vessels • Mediastinal shift (toward collapse) • Crowding and reorientation of

pulmonary blood vessels

• Compensatory hyperinflation• Bronchial rearrangement • Cardiac rotation • Displacement of diaphragm• Rounded pulmonary margins • Displacement of pleural fissures • Changed location of abnormal

structures

Signs of Incomplete Lung Expansion

191582 9-year-old, MC, Weimaraner

Incomplete Lung Expansion

• Anectasis– Lungs never expanded

• Atelectasis– Lungs previously expanded then collapsed

• Collapse– Same as atelectasis, but often used when more severe– Less severity may be indicated by “partial collapse”

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Atelectasis or Collapse

• Related to physiology of lung expansion– Elasticity– Compliance– Airway patency– Surface tension

Relaxation Atelectasis

• Lung does not expand due to the unopposedtendency for lung to collapse due to elasticity– Exhalation– Pleural fluid– 100% oxygen– Pneumothorax– Shallow breathing– Gravity dependent– Space-occupying lesion

Relaxation Atelectasis

176633 165188

0.6-year-old, M,Siberian husky

5-year-old, FS,mixed-breed dog

Relaxation Atelectasis

186202 11-year-old, FS, mixed-breed dog

Obstructive Atelectasis

• Lung not expanded due to absorption ofalveolar gas without replacement due toairway obstruction– Infectious bronchitis or pneumonia– Mucous plugging (eg, asthma)– Ciliary dyskinesia– Foreign body– Neoplasm

Obstructive Atelectasis

186808 13-year-old, FS, DSH Cat

L

R

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Obstructive Atelectasis

Basal cell carcinoma

186808 13-year-old, FS, DSH Cat

Obstructive Atelectasis

11-year-old, MC, DLH Cat

5-year-old, M, Labrador Retrieverwith Chronic Coughing

220061 Compare lung expansion on both laterals

5-year-old, M, Labrador Retrieverwith Chronic Coughing

220061

Compare lung expansion on both laterals

Bronchial Foreign Bodies

• Visible foreign body• No radiographic sign• Obstructive atelectasis

– Chronic– Complete obstruction

• Obstructive emphysema– Acute– Partial obstruction

Cat found dead in cageTracheal foreign body (kibble)

Feline Asthma

194119 Collapsed & hyperinflated lung lobes

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Cicatrizing Atelectasis

• Lungs do not increase in volume under normalrespiration due to reduced compliance– Chronic immune-mediated lung disease– Chronic idiopathic fibrosis– Radiation pneumonitis– Chronic pneumonia

Compliance

• Relationship between volume & pressure

Volume

Pressure

Cicatrizing Atelectasis

14-year-old, MC, West Highland White terrierwith chronic idiopathic pulmonary fibrosis144037

Pulmonary Fibrosis

140648 Unspecified age, FS, mixed-breed dog

Restrictive Pleuritis

226429 1-monthLLAT RLATVD

Adhesive Atelectasis

• Lungs do not expand due to lumen surfaces ofalveoli sticking from surfactant abnormality– Neonatal respiratory distress syndrome– Acute respiratory distress syndrome– Pulmonary thrombosis

Surfactants (surface active agents) are compounds that lower the surface tension between two liquids or between a liquid and solid. Surfactants may act as detergents, wetting

agents, emulsifiers, foaming agents, and dispersants.

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Adhesive Atelectasis

Pre-mature, F, Thoroughbred horse

Ventilation and Perfusion

• Goal is to match ventilation of air (V) with theperfusion of blood flow (Q) to the lung– Ventilation perfusion quotient (V/Q) is the amount of

air that is breathed in and perfused into the blood

• V/Q affected by– Gravity– Normal physiology– Disease

Lung Zones

223822

1

2

3

V > Q

V = Q

V < Q

Gravity Affects V/Q

217161

4-year-old, F, Saanan Goat

Blood Pooling

878375

8-year-old, F, Golden Retriever

Atelectasis

Gravity Affects V/Q

• Zone 1: V>Q– Hypotension– Hyperexpanded alveoli

• Zone 2: V=Q– Normotensive– Normally expanded

• Zone 3: V<Q– Hypertension– Collapsed alveoli

Physiologic Regulation of V/Q

• Normal breathing = tidal breath– Half of the alveoli are normally collapsed

• Improve V/Q across lung zones– Take a deep breath– Hypoxic vasoconstriction

• The alveoli that are not well ventilate stimulatearteriole vasoconstriction to those alveoli andincreases blood flow to the rest of the lung

– Reduces size of Zone 3– Increases size of Zone 2

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Hypoxic Vasoconstriction

• Normal Lungs– Only well ventilated alveoli receive blood flow– Poorly ventilated alveoli are not perfused

215746

Hypoxic Vasoconstriction

223822

1

2

3

V > Q

V = Q

V < Q

Lung

Zo

neHypoxic Vasoconstriction

• Pulmonary Inflammation– Increased vasodilation

• Perfusion to non-ventilated lung• V/Q mismatch

215746

V < QDecreased oxygen saturation

“Functional R-L shunt”

Atelectasis

• Can be a technical complication• Can cause decreased V/Q

– An important component of the disease processdue to reduced gas exchange

– A source of “shunt” in anesthetized patients• Hypoxic vasoconstriction ineffective in anesthesia

219400

Atelectasis as a Diagnostic Clue

• Indicator of lung disease and process• Differentiating types of atelectasis

– Not always possible– Regional vs diffuse– Acute vs chronic

The Fully Expanded Lung

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Importance of Lung Size

Altered Lung Opacity

Reduced Size

TechnicalComplication

Incidental

Obscured Pathology

Misidentified Pathology

Disease

Normal-to-Increased Size

Disease

PPV

The Fully Expanded Lung

• The opacity of the lung• Appearance of increased opacity• Macroscopic distribution of altered opacity

Lung Opacity

• Decreased• Normal• Increased

Decreased Lung Opacity

Congenital lobar emphysema

Courtesy of Dr. Anthony Fischetti

Hypovolemia

163034

Appearance of Increased Lung Opacity

• Classic description– Interstitial pattern– Alveolar pattern– Bronchial pattern– Vascular pattern– Mixed pattern

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Appearance of Increased Lung Opacity

• Classic description– Interstitial pattern– Alveolar pattern– Bronchial pattern– Vascular pattern– Mixed pattern

• Variable terminology– Interstitial

• Unstructured• Structured

– Nodular

– Reticular

– Alveolar• Alveolointerstitial• Airspace

Appearance of Increased Lung Opacity

• Classic description– Interstitial pattern– Alveolar pattern– Bronchial pattern– Vascular pattern– Mixed pattern

• Variable terminology– Bronchial

• Bronchointerstitial• Peribronchial

– Vascular• Bronchovascular

Disease of Pulmonary Blood Vessels

• Vascular pattern– Pulmonary artery enlargement– Pulmonary venous congestion– Pulmonary over-perfusion

203393

Patent Ductus Arteriosus

Disease of the Pulmonary Parenchyma

• Classic description– Interstitial pattern– Alveolar pattern

Clear glassGround glassOpaque glass

Respiratory Zone

Disease of the Pulmonary Parenchyma

Interstitial Alveolar

*Terms apply to incompletely and fully inflated lungs

Ground-glass opacity* Consolidated*

Fleischner Society: Glossary of Terms for Thoracic ImagingRadiology 2008;246(3):697-722.

Disease of the Pulmonary Parenchyma

In all 3 examples, the lungs are fully expanded

Relates to the ability to see the pulmonary blood vessels

Partially aeratedGroundglass opacity

Void of airConsolidated

204095212701 193750

Fully aerated

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Disease of the Pulmonary Parenchyma

227765

Disease of the Pulmonary Parenchyma

201539 221546

Relates to the ability to see the pulmonary blood vessels

Mass

Ground-glass opacity Consolidated

Atelectasis

Consolidated Lung (Pulmonary Blood Vessels Obscured)

224090

Without air bronchograms

With air bronchograms

Groundglass Opacity vs. Consolidation

• Due to differences in lung density– Important for patient management– Defined by how much air is displaced from lungs

• Filling the alveolar spaces with fluid or cells• Filling the alveolar walls with fluid or cells• Partial or complete collapse• Increased blood flow

Air Is Displaced From The Lungs By

Attenuation of the voxel or X-ray path

A. Normal lungB. AtelectasisC. Hyperemia

D. Thick interstitiumE. Filled alveoliF. Thick alveolar wall & filled alveolar space

Air Is Displaced From The Lungs By

Attenuation of the voxel or X-ray path

A. Normal lungB. AtelectasisC. Hyperemia

D. Thick interstitiumE. Filled alveoliF. Thick alveolar wall & filled alveolar space

A B C

D E F

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Acute Respiratory Distress Syndrome

• Lung inflammation can cause acute lung injury (ALI)

218700

Lung Inflammation

• Inhaled– Burns– Infections– Chemicals

• Hematogenous spreadof inflammatory mediators– Ischemic gut– Infection elsewhere

Lung is “first stop” for inflammation elsewhere in the body

Lung Inflammation

• Acute respiratory failure• Chronic respiratory failure

Pulmonary Pathophysiology

• Acute respiratory failure– Leaky capillaries & vasodilation

• Pulmonary edema– Decreased diffusion/hypoxia

– Flooding of alveoli• V/Q mismatch (R-L shunt)

– Decreased surfactant• Decreased compliance

• Chronic respiratory failure– Fibrosis

• Decreased diffusion• Decreased compliance

Pulmonary Pathophysiology

• Acute respiratory failure– Leaky capillaries & vasodilation

• Pulmonary edema– Decreased diffusion/hypoxia

– Flooding of alveoli• V/Q mismatch (R-L shunt)

– Decreased surfactant• Decreased compliance

• Chronic respiratory failure– Fibrosis

• Decreased diffusion• Decreased compliance

Pulmonary Pathophysiology

• Acute respiratory failure– Leaky capillaries & vasodilation

• Pulmonary edema– Decreased diffusion/hypoxia

– Flooding of alveoli• V/Q mismatch (R-L shunt)

– Decreased surfactant• Decreased compliance

• Chronic respiratory failure– Fibrosis

• Decreased diffusion• Decreased compliance

Neutrophil influx damagesType II pneumocytes

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Pulmonary Pathophysiology

• Acute respiratory failure– Leaky capillaries & vasodilation

• Pulmonary edema– Decreased diffusion/hypoxia

– Flooding of alveoli• V/Q mismatch (R-L shunt)

– Decreased surfactant• Decreased compliance

• Chronic respiratory failure– Fibrosis

• Decreased diffusion• Decreased compliance

It is Understandable

• Why lung patterns arecommonly thought to refer tothe microscopic localization oflung lesions– Interstitial pattern– Alveolar pattern

• However, the appearancesrelates to severity of airdisplacement and not theunderlying cause of disease

Compare, For Example

• Left congestive heart failure causesincreased hydrostatic pressure– Interstitial pattern

• Leaky capillaries & vasodilation– Alveolar pattern

• Flooding of alveoli

Compare, For Example

201757 Metastatic mammary adenocarcinoma Carcinoma 201539

Disease of the Pulmonary Parenchyma

• Groundglass opacity or interstitial pattern– Affected lungs are partially aerated

• Consolidation or alveolar pattern– Affected lungs are void of air

What the pathologist calls “interstitial disease” is differentfrom what a radiologist calls an “interstitial pattern.” Suter & Lord

Disease of the Bronchovascular Bundle

• Classic description– Bronchial pattern

174941

Normal

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Disease of the Bronchovascular Bundle

• Classic description– Bronchial pattern

Differentiate bronchovascular disease from an air bronchogram (parenchymal disease)

Conducting Zone

Bronchovascular Pattern

• Bronchovascular bundle– Bronchi– Arteries– Veins– Lymphatic vessels

• Bronchiolovascular bundle– Bronchioles– Arterioles– Venules– Lymphatic vessels

Bronchovascular

Normal

Bronchovascular Pattern

214640

Blastomycosis

217042 10-year-old, FS, German Shepherd

Bronchiectasis

202189 206507

Bronchiectasis

183162 6-weeks later lung and bronchus are better aerated

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Some Take-Home Messages

• The appearances of increase opacity differentiates– Bronchovascular diseases– Parenchymal diseases– Nodular diseases

Some Take-Home Messages

• Different appearances of parenchymal diseaseis determined by the ability to see the margins ofthe pulmonary blood vessels– This is helpful for determining disease severity

and not forming the differential diagnosis

Some Take-Home Messages

• Interstitial pattern or groundglass opacityindicates that the lungs are partially aerated– Not that disease is necessarily localized to interstitium

• Alveolar pattern or consolidation indicatesthat the lungs are void of air– Not that disease is necessarily localized to the

alveolus

• Bronchial or bronchovascular pattern indicatesthat disease is centered in or around thebronchial wall

Forming the Differential Diagnosis

• Lung lobe size• Opacity of the lung• Appearance of increased opacity• Macroscopic distribution / shape of lesions• Additional signs

Macroscopic Distribution of Lung Disease

• Cranioventral• Caudodorsal• Diffuse• Lobar• Locally extensive

– “sublobar”

• Focal• Multifocal• Patchy/asymmetric

• Bronchocentric• Peripheral• Central• Secondary pulmonary lobule

– Centrilobular– Panlobular– Perilobular

Macroscopic Distribution of Lung Disease

• Cranioventral• Caudodorsal-to-diffuse• Focal• Multifocal• Patchy/asymmetric

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Cranioventral & Caudodorsal Distributions Cranioventral Parenchymal Disease

• Pneumonia– Aspiration– Bronchopneumonia

• Hemorrhage• Neoplasm• Lung lobe torsion

215570

Caudodorsal-to-Diffuse Parenchymal Disease

• Cardiogenic pulmonary edema• Non-cardiogenic pulmonary edema

– Upper airway obstruction– Toxin inhalation– ALI (SIRS/ARDS)– Near drowning– Neurogenic– Vasculitis– DIC

• Lymphoma

161844

Example of Diffuse Distribution

218301

Diffuse Parenchymal vs. Generalized-Random

Normal Generalized random Diffuse

Diffuse Bronchovascular Disease

• All causes of bronchitis– Allergic– Infectious– Immune mediated

• Lymphatic spread of tumor• Early pulmonary edema

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Diffuse Bronchovascular Disease

199892 Feline Asthma

Bronchocentric Distribution

• Bronchocentric– Involves the pulmonary parenchyma around the

bronchovascular bundle

Bronchocentric Differential Diagnosis

• Inflammatory• Neoplasm

205295

Lobar/Sublobar Distributions

Lobar Parenchymal Disease

• Pneumonia– Aspiration– Bronchopneumonia

• Hemorrhage• Neoplasm• Lung lobe torsion

187357

Sublobar Parenchymal Disease

• Pneumonia– Aspiration– Bronchopneumonia

• Hemorrhage• Neoplasm

187862

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Aspiration Pneumonia Left Cranial Lobe (Caudal Part)

201498

LLAT RLAT

Focal Distribution

• Focal– Milliary (<1 mm)– Nodule (<3 cm)– Mass (>3 cm)

Locally extensive

Focal/Multifocal Differential Diagnosis

• C.H.A.N.G.CystHematomaAbscessNeoplasmGranuloma

202324 218657

Ossifying Pulmonary Metaplasia

209110

Patchy Distributions

1 lesion multiple lesions

Patchy/Asymmetric Distribution

• Does not conform to other distributions

177263 Trauma

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Patchy/Asymmetric Parenchymal Disease

• Trauma• Infection• Neoplasia• Hemorrhage• Inflammation

212351Rodenticide toxicity

Central & Peripheral Distributions

• Central lung (hilar)• Central lobe• Peripheral lung• Peripheral lobe

Hilar

224932 1-day apart; possible resuscitation trauma

Secondary Pulmonary Lobule Distributions

A. CentrilobularB. PanlobularC. Perilobular

Perilobular & Centrilobular Distributions

Perilobular Centrilobular

May appear nodular

Mixed Pattern

• Use cautiously– Often there is a mix, but we conclude the most severe

• Not the same as an asymmetric distribution

197843

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Hemangiosarcoma

226447 8-year-old, FS, German Shepherd

Additional Signs

• Pulmonary– Bullae– Cavitary– Mineralization

• Non-pulmonary– Pleural fluid– Heart enlargement– Lymph node enlargement

177238

Lung Lobe Torsion

188929

Pulmonary Adenocarcinoma

225950 12-year-old, MC, DSH

Pulmonary Thromboembolism

192827 6-year-old, FS, Labrador retriever

Summary

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Summary

• Pulmonary anatomy• Selecting the imaging examination• Principles of radiographic interpretation• The incompletely expanded lung• The fully expanded lung• Summary

Key Points

• Pulmonary imaging interpretation– Anatomy– Pathophysiology– Physical principles of imaging modalities

• Pulmonary patterns are a combination of signs– Degree of lung expansion– The opacity of the lung– Appearance of increased opacity– Macroscopic distribution of altered opacity– Additional signs

Lung Expansion & Opacity

• Size– Small– Normal– Enlarged

• Opacity– Decreased– Normal– Increased

Appearance

• Bronchovascular disease• Parenchymal disease• Nodular disease• Vascular disease

Appearance

• Bronchovascular disease– Conducting zone

• Parenchymal disease– Respiratory zone

• Nodular disease• Vascular disease

Appearance

• Bronchovascular disease• Parenchymal disease

– Groundglass opacity– Consolidation– Atelectasis– Collapse

• Nodular disease– Milliary– Nodule– Mass

• Vascular disease

How much gas is displacedfrom the lungs

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Distribution

• Cranioventral• Caudodorsal• Diffuse• Lobar• Sublobar/locally extensive• Focal• Multifocal• Patchy/asymmetric• Secondary pulmonary lobule

Quantify Disease Severity

• Normal• Questionable• Mild• Moderate• Severe

• Normal• Small• Medium• Large

Putting It Together

• Severe, cranioventral, lung consolidation• Large, focal, lung mass• Large, focal, cavitary lung mass• Moderate, generalized random, nodules• Moderate, diffuse, atelectasis• Mild, diffuse, groundglass pattern• Mild, diffuse, bronchovascular pattern

Severity, distribution, appearance

Pulmonary Pattern Interpretation

• Definitive diagnosis• Differential diagnoses• No diagnosis possible