VCT vs HD CCTA ExamVCT vs HD CCTA Exam92% Dose Reduction92% Dose Reduction

James P Earls MD

Fairfax Radiological Consultants, Fairfax VA

Inova Fairfax Hospital, Falls Church VA

History

• 53 yr old male– Had chest pain 2 years ago– Echo, ECG and nuclear stress study all negative

• CCTA 2006– retrospectively gated study on VCT system– showed 90% LAD– Cath confirmed; 5.0 mm bare metal stent placed

• CCTA 2009– Some recurrent CP several months ago– Prospectively gated, ASIR reconstruction on HD system– No evidence of restenosis

Scan Techniques• GE HD CT750

• Scan parameters

– Prospective gating

– 0 msec padding

– 30% Volume ASIR

– High Res mode

– 350 mA, kV 120

• Contrast

– 80 cc Visipaque @ 5.5 cc/sec

• Radiation Dose

– CTDIvol 8.22 mGy

– DLP 115 mGy-cm

– Effective dose 1.61 mSv

• GE VCT

• Scan parameters

– Retrospective gating

– ECG modulation

– 717 mA, kV 120

• Contrast

– 80 cc Visipaque @ 5.5 cc/sec

• Radiation Dose

– CTDIvol 78.6 mGy

– DLP 1419 mGy-cm

– Effective dose 19.8 mSv

92% Dose Reduction!!!

Whole Heart View

VCT Exam 8/2006 HD Exam 2/2009

Tree VR View

VCT Exam 8/2006 HD Exam 2/2009

MIP View

VCT Exam 8/2006 HD Exam 2/2009

LAD

VCT Exam 8/2006 HD Exam 2/2009

LAD

VCT Exam 8/2006 HD Exam 2/2009

Cath Views

Pre-Stent Post-Stent

Cath Views

VCT (8/2006) Cath (8/2006)

Cath Views

HD study (2/2009) Post-Stent (8/2006)

CCTA on the HD