MDCT Adaptations for HRCT Imaging MDCT

Transcription

MDCT Adaptations for HRCT Imaging MDCT
Johnny Vlahos, MD: Adaptations for HRCT
imaging
May 15, 2008- 9:10 AM
MDCT HRCT –When and where?
• Routine MDCT studies
MDCT Adaptations for HRCT
Imaging
Johnny Vlahos
Assistant Prof. Radiology - NYU Medical Center
Consultant – St. George’s Hospital London
SCHOOL OF
MEDICINE
– Reconstructed at 3-5mm collimation
– Additional reconstruction of 1q 10mm data set for every
patient
– Evaluation for incidentally detected emphysema,
fibrosis, bronchiectasis etc.
• “HRCT” indication
– Step and shoot MDCT HRCT
– Volumetric acquisition and retrospective 1mm HRCT
recon
NEW YORK
UNIVERSITY
Volumetric MDCT HRCT
Advantages
• Speed → ↓Motion Artifacts
• Comprehensive study
Volumetric MDCT HRCT – Motion Effect
Disadvantages
• Dose
– Anatomic Evaluation
– Clinician Understanding
– Children
– Multiple
M lti l repeatt studies
t di
• Volumetric HRCT
– Contiguous axial HRCT
– MPR, 3-D tools
– Quantitative imaging
Volumetric MDCT HRCT – Motion Effect
Volumetric HRCT – Image quality
• Step and shoot non-contiguous (NC) HRCT
– MDCT equivalent to SDCT
• Retrospective recon of MDCT data v NC HRCT
“Ground
Ground Glass
Glass”
Micronodular
Sarcoid
Stanford Radiology 10th Annual Multidetector
CT Symposium
–R
Reduced
d d motion
ti artifacts
tif t
– For early generation MDCT anatomic visualization better
on NC HRCT
– Equivalent at 16-detector
– Likely equivalent or better for 64-detector MDCT HRCT
Vikgren. Acta Radiologica 2007; 48:956-61
Sumikawa Rad Medicine 2005; 23:539-44
Studler AJR 2005; 185:602-7
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Johnny Vlahos, MD: Adaptations for HRCT
imaging
Volumetric HRCT – Contiguous Data
May 15, 2008- 9:10 AM
Volumetric HRCT – Contiguous Data
Volumetric HRCT – Contiguous Data
Volumetric HRCT – Contiguous Data
Volumetric HRCT - Bronchiectasis
Advantages
• Avoids missing bronchiectasis due to sampling
• Better appreciation of non-tapering
• Focal mucoid impaction not interpreted as nodules
• Less motion artifacts
Remy-Jardin. Eur Radiol 2003;13:1165
Sung. J Comput Assist Tomogr 2003;27:490
Chooi. Br J Radiol 2003;76:536
Stanford Radiology 10th Annual Multidetector
CT Symposium
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Johnny Vlahos, MD: Adaptations for HRCT
imaging
Volumetric HRCT - Bronchiectasis
May 15, 2008- 9:10 AM
Coronal Evaluation - Bronchiectasis
Detection
• Volumetric 1mm axial MDCT vs NC HRCT
• 61 patients with bronchiectasis
– 7 MDCT only
• Of 479 lobes
– 25 lobes cylindrical, 11 varicose and 4 cystic detected
only by volumetric MDCT HRCT
Dodd AJR 2006 187(2):414-20
Coronal Evaluation - Bronchiectasis
MPRs ↑
Detection of bronchiectasis
Observer agreement
Distribution agreement
Particularly mild cylindrical
Remy-Jardin. Eur Radiol 2003;13:1165
Sung. J Comput Assist Tomogr 2003;27:490
Chooi. Br J Radiol 2003;76:536
Coronal Evaluation - Bronchiectasis
Volumetric HRCT – Coronal Evaluation Sarcoidosis
Coronal MPRs in Diffuse Disease
•Additional info compared to axial in 22%
•Lesion conspicuity/distribution
•Equivalent to axial in 72%
Arakawa. J Thorac Imaging 2004; 19:24-31
Stanford Radiology 10th Annual Multidetector
CT Symposium
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Johnny Vlahos, MD: Adaptations for HRCT
imaging
May 15, 2008- 9:10 AM
Volumetric HRCT – Coronal Evaluation
UIP-IPF
Volumetric HRCT – Coronal Evaluation
Ground Glass--Edema
Histiocytosis X
Alveolar Proteinosis
Coronal Evaluation – Tree in Bud
“Lateral”
“PA”
Sarcoidosis
Pulmonary MIPs– Nodule Characterization
1mm
1mm MPR
3mm MIP
5mm
1mm MPR
Stanford Radiology 10th Annual Multidetector
CT Symposium
5mm MIP
15mm MIP
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Johnny Vlahos, MD: Adaptations for HRCT
imaging
Pulmonary MIPs – Tree-in Bud TB
1mm HRCT
5mm MIP
MDCT HCRT – Emphysema Evaluation
May 15, 2008- 9:10 AM
Thick section Pitfall – Miliary TB
7mm axial
1mm HRCT
MDCT HCRT – Emphysema Evaluation
Quantitative Emphysema Evaluation
Stanford Radiology 10th Annual Multidetector
CT Symposium
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Johnny Vlahos, MD: Adaptations for HRCT
imaging
May 15, 2008- 9:10 AM
MDCT Adaptations for HRCT
Imaging
Thank You
SCHOOL OF
MEDICINE
NEW YORK
UNIVERSITY
Stanford Radiology 10th Annual Multidetector
CT Symposium
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