Radiology of the Chest #2 Flashcards
(38 cards)
DDx: air-space disease
•Pneumonias (some overlap with interstitial)
–Pneumococcal (lobar), Leigionella, PCP (late), etc
•Aspiration
•Pulmonary alveolar edema
–Cardiac (late CHF), non-cardiac (drugs, drowning, etc)
•Tuberculosis (some overlap)
•Pulmonary Hemorrhage
•ARDS (adult respiratory distress syndrome -overlap)
•Chronic alveolar Dz
Miliary TB
- miliary pattern: interstitial form of TB
- Diffuse, bilateral hilar adenopathy
- Good lung aeration maintained
Pneumothorax on US
Absence of:
- Pleural Sliding
- No comet tail artifact
M-Mode to confirm
- ”Ocean + beach” is normal
- No beach or “barcode” = pneumo
Lung Point
-Spot where lung moves in one area, not in adjacent area: 100% sensitive
ARDS
delayed dyspnea, hypoxia, alveolar edema
Congestive HF on CXR
•Fluffy, hazy air space densities •Fluid in fissures, effusions •Kerley B’s, peribronchial cuffing •Cardiomegaly –common •Cephalization –Vessels prominent toward apices •Engorged, hazy, “plump” pulmonary vasculature –Due to pulmonary venous hypertension •Either/mixed interstitial/alveolar
Emphysema characteristics
- Hyperinflation: increased space between 7-10 ribs
- Flat diaphragms
- Narrow cardiac silhouette
- Increased retrosternal space on lateral -“barrel chest”
- +/-blunting of costophrenic angle
- Bullae
Lung Cancer Patterns on CXR
- Pulmonary nodule or mass
- Mediastinal mass/hilar enlargement
- Lobar atelectasis
- Obstructive pneumonia
- Malignant effusions
- Chest wall mass
- Metastases
Malignant pulmonary nodule characteristics and workup
•Malignant characteristics –>30yo, smoker, risks –>3cm, recent growth –Irregular shape –Poorly defined edges or spiculated –Asymmetric or no calcification –Cavitary
•CT, PET scan, biopsy
Chest trauma imaging
•eFAST–ultrasound immediately at bedside –Lung, cardiac •CXR -standard –Portable supine or semi-recumbent AP •CT -standard –With IV contrast, high sensitivity •MRI –Spinal cord injury; when ptis stable •Fluoroscopy –Esophageal tears
Air space disease
•Air-space Dz characteristics –Air Bronchograms (space around air-filled bronchi is filled w/ fluid making bronchi visible) –Fluffy, hazy infiltrate –Confluent with ill-defined edges –Consolidations, lobar –DDx: most pneumonias, TB, late CHF –Silhouette sign
Pneumoperitoneum
- “Free Air” under the diaphragm
- Right usually seen first, easier to see
- Perforated viscous (hole in the bowel)
- Trauma
- Post-surgical
- Post-procedural
- Lateral CXR best for small perfs–see air under diaphragms
Pulmonary embolus
•CXR first in all for alternate Dx –Atelectasis, effusion, elevated hemidiaphragm –Hampton’s hump, Westermark sign (late) •CT scan with IV contrast –PE protocol –Moderate to high risk –New Gold Standard •V/Q scan –If cannot use contrast, consider if pregnant •Pulmonary angiogram
Mediastinal Masses, enlargement
Hallmark = wide appearing mediastinum
Anterior (retrosternal) -4 Ts
- Thyroid
- (Terrible) Lymphoma
- Thymoma
- Teratoma
Middle
- Lymphadenopathy
- Cancers
- Aortic Aneurysm
Posterior
- Aortic Aneurysm
- Neurogenic tumors
Difference in CXR for atelectasis vs pneumonia
Atelectasis: volume loss, ipsilateral shift of mediastinal structures, linear wedge shaped opacification, in lobar collapse apex is at the hilum
Pneumonia: normal or increased volume, no shift in mediastinal structures, air space dz, no apex
Benign pulmonary nodule characteristics and workup
•Benign characteristics –<30yo, no risks –Small <3cm –Round, solid –Well defined edges –No growth in 2 yrs –Central calcification
•Work-up -old CXR
–Repeat q 3mos first yr
–Q 6mos in 2nd yr
Aspiration pneumonia
usually favors lower lobes (if pt was supine)
Foreign body
•Children < 5 most common •In the bronchi, trachea or esophagus? •CXR: PA +lateral -to locate –Collapse of lung/atelectasis –Aspiration –FB must be radiopaque to see it •Bronchoscopy
Interstitial disease
•Interstitial Dz: •Supportive structures of air-spaces affected •Usually bilateral •Masses, dots, lines, thickening •Discrete “particles” of Dz •No lobar margins •DDx: –Some pneumonias, usually atypical: viral, fungal, etc –Systemic Dz –sarcoid, RA, etc –Cancer, mets –Pulmonary fibrosis, occupational –TB –cavitary lesion, milliary
Atelectasis
•Incomplete aeration/expansion of the lung –no air there
•Volume loss causes “collapse” –white on CXR
•Structures shift to sameside, fissures displaced
•Major Types:
•Subsegmental:“discoid”, “plate-like”, linear
–Common condition: pleuritic pain; post surgery, trauma, scarring
•Compressive: with effusion, pneumothorax, mass
•Obstructive: partial or complete
–Lobar collapse, opacified hemithorax
•Round: pleural based, post effusion/dz
Thoracic aortic aneurysm
High suspicion w/:
- Chest, back pain
- Risks, presentation
CXR suspicious:
- wide mediastinum
- tortuous aorta
- L pleural effusion common
CT angio, echo
Pulmonary edema on US
Normal lung:
- See the pleural line move with respiration
- See horizontal A-lines, “comet tail” artifact
Pulmonary Edema:
- See B-lines
- Bright, vertical, obliterate the A-lines, fill the screen, bilateral
Pneumonia: unilateral or one area of B-lines and “hepatization”
Silhouette sign - structure obscured and location of dz
- Ascending aorta - RUL
- R heart border - RML
- R hemidiaphragm - RLL
- Descending aorta - LUl or LLL
- L heart border - Lingula of LUL
- L hemidiaphragm - LLL
Pneumothorax
•Lucent lung, no lung markings (not symmetric!)
•Visceral pleura line visible
•Check apices and edges!
•Expiratory upright filmor Lateral decubfilm if subtle
•Deep sulcus sign in supine ptor with tension pntx
-CT best for small pntx
Obstructive lobar atelectasis
•Lobar collapse -obstructing tumor, FB, etc
•Opacificationwith evidence of volume loss
–Tracheal deviation
–Mediastinal deviation
–Elevated hemidiaphragm
–Upward bowing of fissures
–Hyperinflation remaining lung on same side
–Rib cage narrowing
