HRCT Interpretation

1. HRCT Interpretation Padmanabhan Krishnan, MD

3. Raoof, S. , CHEST 2006; 129:805

5. Secondary Pulmonary Nodule  Basic unit of lung structure and function  Smallest unit of lung structure marginated by interlobular septa  Septa more peripheral, less or absent centrally  Polyhedral 10-25mm diameter  Terminal bronchiole supplies the SPL  Arteries paired with bronchi  Veins run in the periphery of lobule  Lymphatics are along axial skeleton perivascular peribronchial up to terminal bronchioles and peripheral along interlobular septa and pleura  SPL contains 5-15 acini – 8mm dia  Acinus is the structure distal to end terminal bronchiole (30,000 TB) and contains 2–5 generation of RB and alveolar duct and alveolar sacs (300 million)  End terminal bronchiole 2.5mm from interlobular septae and pleura  2nd generation RB site of small particle deposition less than 5 micron  HRCT: • PA > 0.2mm D at which point are present the distal terminal bronchiole, and 1st generation RB (not seen) • Acini at distal tip of peripheral branching artery

8. Abnormal secondary lobule  Lymphatic distribution  Nodular - perilymphatic ● SP, septal, axial ● SARC, SIL, BERY, Kap, lymphoma  Septal thickening ● Interlobular ● LC  Lobular / Acinar distribution – fibrosis  Inter / Intralobular septae, reticular, honeycomb  UIP, NSIP, CHP, Asbestosis  Vascular distribution  Nodular – random ● SP, septal, non-axial ● Mets, miliary  Septal thickening – interlobular ● VOD, CH, MS  Centrilobular nodule - tree-in-bud ● Tumor embolism  Airway distribution  Centrilobular nodule - Tree-in-bud ● Bronchiolitis  Centrilobular nodule – ground glass ● SAHP, RBILD  Centrilobular nodule and ectasia ● M. avium, DPB  Lobular / Acinar distribution - filling  Ground glass, airspace, crazy paving ● COP, CEP, AP, BAC

9. Raoof, S. , CHEST 2006; 129:805

11. Abnormal secondary lobule  Lymphatic distribution  Nodular - perilymphatic ● SP, septal, axial ● SARC, SIL, BERY, Kap, lymphoma  Septal thickening ● Interlobular ● LC  Lobular / Acinar distribution – fibrosis  Inter / Intralobular septae, reticular, honeycomb  UIP, NSIP, CHP, Asbestosis  Vascular distribution  Nodular – random ● SP, septal, non-axial ● Mets, miliary  Septal thickening – interlobular ● VOD, CH, MS  Centrilobular nodule - tree-in-bud ● Tumor embolism  Airway distribution  Centrilobular nodule - Tree-in-bud ● Bronchiolitis  Centrilobular nodule – ground glass ● SAHP, RBILD  Centrilobular nodule and ectasia ● M. avium, DPB  Lobular / Acinar distribution - filling  Ground glass, airspace, crazy paving ● COP, CEP, AP, BAC

12. Raoof, S. , CHEST 2006; 129:805

13. HRCT – ILD/DPLD Nodular Lymph- hematogenous Reticular Honeycomb Cystic Septal Interlobular Airspace Ground glass Crazy paving PL SARC/ BRYL Silicosis Lymphoma Kaposi Random Mets Miliary TB UIP IPF RA HPS CHP Asbestosis drug parenchymal LCH (gg) LAM LIP (gg) Airway Bronchiectasis venous MS PVOD PCH COP CEP Alv proteinosis Alv mcrlithia DIP AIP AHP SAHP BAC lymphatic LC Lymphoma sarcoid NSIP (gg) AIP (gg)Bronchiolar Bronchiolitis SAHP (gg) RB-ILD (gg) LCH (gg) Vascular tumor emboli

14. HRCT PATTERNS NODULAR PATTERN  lymphohematogenous  Bronchiolar terminal bronchiole  Vascular intralobular artery LYMPHOHEMATOGENOUS  subpleural  on fissures and septae PERYLYMPHATIC RANDOM axial skeleton end of vessels perivascular / peribronchial cavitation upper lobes basilar -sarcoidosis -mets -berylliosis -miliary TB/ histoplasmosis/crypto -silicosis/ CWP -septic emboli -lymphoma -vasculitis -Kaposi's -amyloidosis Raoof S., CHEST 2006;129:805

15. Raoof, S. , CHEST 2006; 129:805

16. Sarcoid perilymphatic

19. sarcoid

23. Lymphoma perilymphatic

25. HRCT PATTERNS NODULAR PATTERN  lymphohematogenous  Bronchiolar terminal bronchiole  Vascular intralobular artery LYMPHOHEMATOGENOUS  subpleural  on fissures and septae PERYLYMPHATIC RANDOM axial skeleton end of vessels perivascular/ peribronchial cavitation upper lobes basilar -sarcoidosis -mets -berylliosis -miliary TB/ histoplasmosis/crypto -silicosis/ CWP -septic emboli -lymphoma -vasculitis -Kaposi's -amyloidosis Raoof S., CHEST 2006;129:805

26. Raoof, S. , CHEST 2006; 129:805

27. METS random

29. Wegener’s random

32. miliary

34. Miliary random

37. HRCT PATTERNS NODULAR PATTERN  lymphohematogenous  Bronchiolar terminal bronchiole  Vascular intralobular artery LYMPHOHEMATOGENOUS  subpleural  on fissures and septae PERYLYMPHATIC RANDOM axial skeleton end of vessels perivascular / peribronchial cavitation upper lobes basilar -sarcoidosis -mets -berylliosis -miliary TB/ histoplasmosis/crypto -silicosis/ CWP -septic emboli -lymphoma -vasculitis -Kaposi's -amyloidosis Raoof S., CHEST 2006;129:805

38. HRCT - Nodular Pattern BRONCHIOLAR  Centrilobular nodules: small airways of secondary lobule  1-3mm away from pleura  Not sub pleural  Not on fissures or septae Primary bronchiolar disease Mixed bronchiolar Sharp branching nodules Peribronchiolar Tree-in-bud ground glass nodules+/-tree-in-bud MAI, MTB sub acute HP Aspergillus respiratory bronchiolitis - ILD DPB, DAB LIP Follicular bronchiolitis Early LCH Immune bronchiolitis – UC metastatic Calcification (CRF) mineral dust bronchiolitis nylon flock workers disease Secondary to bronchiectasis silicosis Vascular • Tree-in-bud/ ground glass tumor embolism Plexogenic arteriopathy of PAH Raoof, S. CHEST 2006; 129:805

39. Raoof, S. , CHEST 2006; 129:805

40. Tree-in-Bud Appearance Bronchiolitis Rare- tumor cell emboli – intralobular artery

41. Tree-in-bud / MAI bronchiolar

43. Bronchiolitis - MTB

44. Subacute HP bronch / peribronch / gg

46. RBILD

47. Avium / DPB

50. HRCT RETICULAR PATTERN - UIP  peripheral reticular lines / inter and intralobular septae  honeycomb  Traction bronchiectasis  None or minimal ground glass  Gradient increasing from apex to base  Skip areas  Diagnostic accuracy high  Idiopathic  Familial  CVD - RA  Drugs – NFT, Busulphan  Asbestosis = basilar – bands – pleural calcification  Chronic HP = upper and midzones  Hermansky-Pudlak syndrome Acute exacerbation of UIP ● above + ground glass ● Peripheral – better prognosis – Fibroblastic Foci+++ ● Diffuse – worse prognosis – DAD AMJRCCM.198:372;2008 AIP ● Diffuse ground glass + airspace ● Traction bronchiectasis ● honeycomb

52. UIP

55. Chronic HP

58. Asbestosis

62. HRCT RETICULAR PATTERN - UIP (acinar fibrosis)  peripheral reticular lines  honeycomb  Traction bronchiectasis  None or minimal ground glass  Gradient increasing from apex to base  Skip areas  Diagnostic accuracy high  Idiopathic  Familial  CVD - RA  Drugs – NFT, Busulphan  Asbestosis = basilar – bands – pleural calcification  Chronic HP = upper and midzones  Hermansky-Pudlak syndrome Acute exacerbation of UIP  above + ground glass  Peripheral – better prognosis – Fibroblastic Foci+++  Diffuse – worse prognosis – DAD AMJRCCM.198:372; 2008 AIP  Diffuse ground glass + airspace  Traction bronchiectasis  honeycomb

63. Acute Exacerbation UIP- peripheral

65. Acute exacerbation UIP- diffuse

68. HRCT RETICULAR PATTERN - UIP (acinar fibrosis)  peripheral reticular lines  honeycomb  Traction bronchiectasis  None or minimal ground glass  Gradient increasing from apex to base  Skip areas  Diagnostic accuracy high  Idiopathic  Familial  CVD - RA  Drugs – NFT, Busulphan  Asbestosis = basilar – bands – pleural calcification  Chronic HP = upper and midzones  Hermansky-Pudlak syndrome Acute exacerbation of UIP  above + ground glass  Peripheral – better prognosis – Fibroblastic Foci+++  Diffuse – worse prognosis – DAD AMJRCCM.198:372; 2008 AIP  Diffuse ground glass + airspace  Traction bronchiectasis  honeycomb

69. AIP HC/gg

74. Reticular Pattern - NSIP inflammation and fibrosis  Predominantly basilar  Significant ground glass  Subpleural sparing low sensitivity, high specificity  No honeycombing, some cystic change  Traction Bronchiectasis Diagnostic accuracy 50%  Cellular NSIP  Fibrotic NSIP  Associated with CVD  Undifferentiated CVD – T. King

75. NSIP- cellular

78. NSIP-fibrotic

81. Cystic Pattern  Parenchymal  Bronchiectasis  Parenchymal LCH  irregular shaped cysts, stellate:3-10mm; upper lobe  Ground glass centrilobular nodules  Air trapping – mosaic patterns  Spares costophrenic angles LAM  Thin walled oval cysts  Normal parenchyma  Pleural effusion-chylous  normal or hyperinflated lung  angiomyolipoma LIP  Ground glass centrilobular nodules  Diffuse ground glass  Thin walled cysts  PCP, papilomatosis, Birt-Hogg-Dube disease

82. LAM

85. LIP

87. PCP

88. Cystic Pattern  Parenchymal  Bronchiectasis  Parenchymal LCH  irregular shaped cysts, stellate:3-10mm; upper lobe  Ground glass centrilobular nodules  Air trapping – mosaic patterns  Spares costophrenic angles LAM  Thin walled oval cysts  Normal parenchyma  Pleural effusion-chylous  normal or hyperinflated lung  angiomyolipoma LIP  Ground glass centrilobular nodules  Diffuse ground glass  Thin walled cysts  PCP, papilomatosis, Birt-Hogg-Dube disease

89. Bronchiectasis Vessel at wall of cyst – signet ring Cyst stacked in tubular orientation Cyst stacked in branching pattern Dilated, irregular, thickened airways Mucus-filled airways Diameter of peripheral airway to accompanying artery = >1 ● HGG ● CD ● ABPA ● tracheobronchomegaly ● CF ● α-1 antitrypsin deficiency ● DPB

90. Bronchiectasis central

94. Distal mucocele

97. Bronchiolarectasis DPB

100. Raoof, S. , CHEST 2006; 129:805

101. Septal Pattern – lymphatic/venous  Secondary lobule outlined- interlobular septum ● Smooth – pulmonary veno-occlusive disease, mitral stenosis, capillary hemangiomatosis, LC ● Beaded – lymphangitic carcinomatosis, lymphoma, lymphangiomatosis, sarcoid Rare = non-Langerhans’ cell histiocytosis (bone+pleura) amyloidosis

102. smooth

103. LC smooth

104. smooth

105. LC beaded

107. PHTN – PA 39mm 39.2mm

108. PHTN and septal thickening ? PVOD

111. Airspace Patterns  Diffuse ground-glass  Patchy consolidation (peripheral)  Inter and intralobular septal thickening / ground glass/crazy paving  Reverse halo/atoll sign  Hogshead cheese sign  Perilobular pattern  Organising pneumonia – COP/BOOP  Chronic eosinophilic pneumonia  Alveolar proteinosis  Desquamative interstitial pneumonitis  Alveolar microlithiasis  Alveolar sarcoid  BAC

112. COP (reverse halo/atoll sign)

113. COP – perilobular pattern

114. Sarcoid- Hogshead cheese

115. AHP/ Hogshead cheese

116. Crazy paving

117. Alveolar Sarcoid

121. Emphysema - CL

123. Emphysema - PA

124. CL + PS emphysema

125. HRCT - ILD/DPLD Nodular PL LH Sarc/Berylliosis Mets Silicosis Miliary TB Lymphoma Kaposi Bronchiolar SAHP RB-ILD LCH Bronchiolitis Acinar fibrosis /Reticular/Honeycomb UIP CHP Asbestosis NSIP AIP Septal / Interlobular Venous Lymphatic CHF LC MS Lymphoma PVOD Acinar filling/ ground glass COP CEP Alveolar proteinosis Alveolar microlithiasis DIP AIP SAHP AHP BAC Hyperlucency Centrilobular emphysema Paraseptal emphysema Panacinar emphysema Cystic Parenchymal Bronchiectasis LCH LAM LIP

126. Inter-observer variation in HRCT Diagnosis 131pts- Royal Brompton Hospital, London Median (range) kw Coefficient of agreement IPF 0.63 (0.48-0.78) NSIP 0.51 (0.27-0.78) Sarcoidosis 0.70 (0.58-0.84) Extrinsic allergic alveolitis 0.60 (0.36-0.78) COP 0.49 (0.06-0.76) Smoking related ILD 0.51 (0.20-0.73) For CT diagnosis of pulmonary embolus Kappa = 0.72-0.9 Aziz ZA, et al Thorax. 2004; 59:506-511

127. Interpretation of lung cysts  Parenchymal cyst •LAM, LIP, LCH, PCP  Acinar cyst •Honeycomb-UIP  Bronchiectatic cyst •ABPA, CF, CD  Centrilobular and panacinar emphysema

128. LAM

129. Acinar cyst - honeycomb - UIP

130. Bronchiectatic cyst

132. CL + PS emphysema

133. Pt with more than one form of cyst CL emphysema + bronchiectasis + honeycomb smoker with asbestosis

136. Bronchiectasis – ILD mimic

143. Centrilobular emphysema – mimic ILD

155. Dilated esophagus

158. Paraseptal Emphysema – mimic ILD

160. CT features of tuberculosis  Cavity  Transbronchial spread – tree-in-bud  Transbronchial and hematogenous

161. Tuberculosis – TB spread

163. Tuberculoma – TB spread

165. Tuberculosis bronchiolitis + hematogenous

168. TB bronchiolitis + hematogenous

172. Mosaic CT Patterns  Ground glass – inflammation/ fibrosis  airway obstruction (best seen on expiration) • COPD • small airway disease  Vascular obstruction • chronic thrombotic pulmonary hypertension • sickle cell disease • vasculitis

173. Airway obstruction

178. Vascular obstruction

181. CTPHTN

185. ground glass

HRCT Interpretation

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Viewers also liked

Viewers also liked (20)

Similar to HRCT Interpretation

Similar to HRCT Interpretation (20)

More from Brian Wells, MD, MS, MPH

More from Brian Wells, MD, MS, MPH (20)

Recently uploaded

Recently uploaded (20)

HRCT Interpretation