iDose4: reduced noise, reduced artifacts, natural appearance 100kV, 188 mAs 5.5 mSv 100kV, 14 mAs 0.4 mSv 100kV, 14 mAs 0.4 mSv FBP FBP iDose4 FBP can result in partially-diagnostic images (centre image) iDose4 prevents photon starvation artifacts and reduces quantum mottle image noise which may mask pathology in the lung apices or elsewhere in the body Courtesy: UCL, Brussels

Iterative reconstruction iDose4 Improved removes the noise in the images & therefore improves the Contrast to Noise Ratio (CNR) iDose4 FBP 120kV, 600mAs 120kV, 600mAs

The iDose 4 reconstruction improves contrast to noise, leading to improved gray/white differentiation Patient: 8 year, Male FBP iDose4 120 kV, 375 mAs, 120 kV, 375 mAs, Courtesy: OHSU, USA 3

Improved Contrast to Noise Ratio & therefore the ability to depict gray/white matter more clearly. This is may be useful in assessment of shaken baby syndrome 120 kV, 210 mAs 120 kV, 210 mAs, 6 month old FBP iDose4 Hopital Robert Debré, Paris, France 4

Note the lack of noise & improved CNR with iDose4 which in this patient ensures the adrenal lesion is clearly depicted. This can be of importance in assessing abdominal pathologies & injuries. FBP iDose4 120 kV, 275 mAs 120 kV, 275 mAs 5

iDose4 reconstruction on this obese patient shows improvement in noise reduction while maintaining good vessel detail. In trauma patients, the ability to clearly visualize the small vessels may enable depiction the source of bleeding. Shows good improvement in noise reduction with good vessel details. Small vessel detail would not be possible with simple smoothing techniques. FBP iDose Courtesy Dr Dobritz, TU Munich, Germany 6

Why iterative reconstruction (iDose4) may help: The spleen is the most commonly injured intraperitoneal organ in blunt trauma. In terms of image quality, there can be pathologies with hyperdense or hypodense appearance. Some splenic infarcts might not have been present on the initial CT scan, however a follow up abdominal scan, may show a new splenic infarction: For example, a CT performed on a patient 10 days after the date of admission may reveal a new hypodense fluid collection which could point an intra-splenic abscess. Why iterative reconstruction (iDose4) may help: Subtle splenic lesions can have subtle variation in HU compared to surrounding tissue i.e. low contrast resolution. Therefor a technique to improve CNR is beneficial follow-up scanning is required hence, keeping radiation dose to minimum is essential.

Note the ability on the iDose4 reconstruction image to visualize lesion in the liver, which is not seen on the FBP image. This improvement in image quality is critical to rule out: contusion, laceration, haematoma, post-traumatic pseudoaneurysm, and splenic infarction iDose increases diagnostic confidence of low dose acquisitions, even in low contrast areas. Lesion visible in liver, segment 6 FBP iDose 140 kg, 1.60 m, 54.7 kg/m2 @ 120 kV, 100 mAs  67% Dose Reduction compared to routine protocol (300 mAs) Courtesy Dr Dobritz, TU Munich, Germany 8

Improved IQ for bariatric imaging through noise reduction results in less suboptimal scans 120 kV, 600 mAs FBP iDose4 Noise in liver = 31.1 Noise in liver = 17.3

FBP vs iDose4 : Obese patients have always posed an image quality problem for CT. Now with iterative reconstruction techniques the common artifacts are reduced & in some cases prevented. FBP iDose4

FBP Note the reduction in noise & therefore the improvement in bony detail. This improvement may enable improved fracture detection iDose4 11

Images recontructed using iDose4 iDose4 enables CTA scans to be acquired at low kV settings without the typical increase in images noise. This ensures a well opacified vessel is clearly seen. Which is essential when looking for occlusion or dissection etc Nov 2009 120kVp, 100mAs, FBP Apr 2010 80kVp, 100mAs, iDose4 Same patient follow up scan. Images recontructed using iDose4 Courtesy :TU Munich, Germany 12

iDose4 reconstruction reduces high frequency streak artifacts FBP Standard Reconstruction iDose4 Artifact Prevention

Vessel injuries if left unidentified can lead to serious complication & death. Therefore the ability to visualize the great vessels without the inherent problem of artifacts caused by scanning through the shoulders is critical & iDose4 reconstruction is essential FBP iDose4 Courtesy: Cleveland Clinic. USA

Trauma patients often are unable to have their arms moved away from their sides during a scan, FBP reconstruction results in artifacts which can mask an injury. The use of iDose4 reduces these artifacts FBP iDose4 Noise in liver = 57 HU Noise in liver = 26 HU 15

The inherent nature of FBP results in artifacts from Metal implants . In the past scan parameters were changed in an attempt to improve image quality Trauma pts often have implants &/or dense foreign bodies The metal artifacts are reduced with the use of iDose4 reconstruction esepcially when combined with metal artifact reduction algorithms

Note the lack of metal artifact This post surgery trauma pt was scanned & the images reconstructed with iDose4 & metal artifact reduction. Note the lack of metal artifact Courtesy : Metro Hospital Cleveland, USA