Appendix

Air bronchogram

Air within bronchi seen within a consolidation.

Airspace

Densities that appear fluffy (like clouds) that are indicative of

consolidation.

Atelectasis

A lung process that results in volume loss. There are various

patterns and types described in the Airway pattern section of

this Guide.

Consolidation

Air space opacities that are fluffy (like cumulous clouds) that

often indicate pneumonia. This is described in more detail in

the lung parenchyma chapter.

Conspicuity

Degree of “conspicuousness.” High conspicuity is an obvious

finding, and a decreased conspicuity is a subtle finding.

Various properties or adjacent structures may alter conspicuity.

Cysts (holes)

Fine lucencies in the lungs indicating long-term or end-stage

lung disease, as described in the interstitial pattern section of

this Guide.

Density

Whiteness, or any area of whiteness, on an image (opacity).

Bones are an example. Imaging densities also include soft

tissues (including, blood/fluid, fat, calcium, and even air low

density).

Horizontal beam

When the x-ray tube is horizontally oriented relative to the

patient and the x-ray beam is parallel to the floor. This is the

only way to effectively demonstrate a fluid level.

Infiltrate

A non-descript term that is often used to indicate an opacity

exists that may represent a consolidation, interstitial pattern, or

atelectasis. From the radiologist to the provider, there is

flexibility in interpretation.

Interstitial

Used to describe linear opacities that are not vessels; rather

may cross vessels at angles not in branching patterns. This is

described in more detail in the lung parenchyma chapter.

Edge

Any visible demarcation between a density on one side and

lucency on the other.

L.R. Folio, Chest Imaging, DOI 10.1007/978-1-4614-1317-2_1,

139

© Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. 2012

140

Appendix

Glossary

Line

A thin density with lucency on both sides or a thin lucency

with density on both sides.

Lucency

Blackness, or any area of blackness, on an image. The trachea

is an example.

Mach (not mock) bands

Center-surround receptive field interactions resulting in

(or effect)

apparent lucencies. These often occur adjacent to curved

densities next to relative lucencies (such as the right atrial heart

shadow).

Nodules

Fine, well-rounded opacities that are larger than vessels on end

(relatively speaking from a peripheral perspective), indicating

an interstitial pattern, specifically dots.

Obliterated

Obscured structure that should otherwise be seen. Other words

that can be used include masked, not seen, or not well

discerned.

Projection

The path of the x-ray beam; can be a frontal projection (either

PA or AP), lateral, or upright (erect), etc.

Reticulations (lines)

Linear opacities in the lungs that crisscross vessels (helping

differentiate them from vessels) indicating a linear interstitial

pattern should be considered.

Shadow

Anything visible on an image; hence, any specific density or

lucency.

Silhouette

Synonym for edge. The loss of an edge constitutes the

“silhouette sign” which occurs by adjacent structures masking

out, e.g., RML consolidate obliterating right atrial edge.

Stripe

Either an edge or a line.

Summation shadow

Anatomic noise of overlapping structures. This often happens

with posterior ribs overlapping vessels and anterior ribs,

mimicking an infiltrate.

Tram track

Two fine parallel densities; essentially parallel lines simulating

train or tram tracks indicating inflammation of bronchi, hence

under airway pattern.

Abbreviations

ARDS

Acute (or Adult) Respiratory Distress Syndrome

AP

Anterior-posterior

AVM

Arteriovenous malformation

BAC

Bronchoalveolar cell carcinoma

CIDA

Chest imaging diagnostic algorithm

COPD

Chronic obstructive pulmonary disease

CXR

Chest X-ray

CPA

Costophrenic angles

Dz

Disease

EG

Eosinophilic granuloma

ER

Emergency room

FHX

Family history

HP

Hypersensitivity pneumonitis

ICU

Intensive care unit

IVC

Inferior vena cava

LCG

Langerhans granulomatosis

LCH

Langerhans cell histiocytosis

Appendix 1: Glossary and Abbreviations

141

Abbreviations

LIP

Lymphocytic interstitial pneumonia

LPA

Left pulmonary artery

LLL

Left lower lobe

LUL

Left upper lobe

MAI

Mycobacterium avium-intracellular

MSK

Musculoskeletal

PA

Posterior-anterior

RLL

Right lower lobe

RML

Right middle lobe

RUL

Right upper lobe

RPA

Right pulmonary artery

SPN

Solitary pulmonary nodule

TB

Tuberculosis

SVC

Superior vena cava

USU

Uniformed Services University