Low Energy, Low Contrast Dose CT in Daily Clinical Practice

Thank you for virtual kind of Russian. Good morning, I'm from Kobe University and probably you know the name of Kobe because of the very nice food. Kobe beef. But also the Kobe is very famous in Japan. Becausw our hospital is the 2nd Northwest National University in Japan. And we have 10 cities. Carriers of impact in the very small scanner in total or 1000 slices. However, we routinely use these four city, including two 64 threads in this carrier's one area detector city an somatom force. This figure summarizes the number of city exam performed in each city scanner in two months. That among them, approximately 1500 city exam or perform at Zomato Force and we perform over 800. Contact her scan as a mother force in two months. And here this figure summarized the overview of city exam performed in samatan force in two months. As you may already know, Tist approximately 70% of all contact has examination were performed with 70 KVP protocol. So the subject of my talk is how are the Y70KV protocol becomes so popular in our institution? As all previous also has already talk about their role in the city, so we can reduce the contrast medium down the opposite half doors at 70 KVP. However, there are several drawbacks. In low Energy City, first, literate if instead photon decrease at low energy. Therefore, in order to compensate sufficient photons for maintaining image quality, we need large tube current and which can be provided by Zomato force. And also take on Drop Box is being Harding Artifact Fridge is more prominent at Lower Kevy setting. Therefore, locate the city has been mainly applied to vascular imaging. So immediately after the introduction of Domino Falls in our institutions, we have applied one hard 20KV protocol with the standard dose of contrast medium to the routine post contrast Body City. However, after the pilot study an Phantom study with shift, all city scan are all routing protocol 270 KBP with reducing the contrast medium down to 60%. So we compare the quantitative and qualitative data between the two historical group. Included, namely safety capability with 60% of contrast medium and 100 capability with the standard or so contrast medium. And a four to 70 KB protocol. We're price me mode of care KB preach can automatically adjust milliampere second based on the user defined cavey. Of course it's a 70KV and also the difference must an the data of to program. And in our routing protocol we give 450 milligrams. I would appropriate body weight to the in the 120 KP protocol. But while in the 70 completely protocol we reduce the total amount of contrast medium down to 270 milligrams item per kilogram body weight and we give the contrast made directly with Saline. And we measure the city body of the organs and vessels and also we assess the degree of beam hardening artifacts at the small Paris shoulder. Metallic out method object and also the contrast medium in the broken vein. Although there are no quite different signal difference between these two groups in body weight. The main city value may ago, sorry, mean. See DDI volume at 70 cavity is significantly smaller than 100K protocol and of course their model Qantas medium in the safety cap vertical is much smaller than 120 KV protocol and please not the range of body weight for Japanese patient. It range from 30 kilogram 295 so this is Japanese population. And also we give the much smaller multiple contrast medium. The degree of a city value of the these orders much greater in 70 capital protocol the 100K VP. So probably we are too conservative to reduce the contrast medium. And similarly, the variable city are the vessels also much greater in 70 cap with protocol except. Broker vein in the bracket of a in the 1:20 KV protocol, the city barrier of the Brocklebank of the contrast injections injected side are much greater than 70 KVP protocol. They're not difference in context to noise ratio. And this patient underwent both 70 KB protocol an 120 can be protocol during her follow up for metastic liver disease as email notice. The degree of contrast enhancement in 70 KV protocol and also the contrast of liver metastasis is equal to or even better than those of 100 KV protocol. But as we expect, beam honey artifact were more prominent in safety protocol in the shoulder and at the level of small pelvis. However, the most of the artifact were moderate or risk in most of the cases. On the other hand, the degree of being hard an artifact in the bracket vein is more prominent in 120. Can we be protocol? For example. The artifact at the shoulder in the 70 K protocol, so much more prominent beam hardening artifact. But the stick artifacts from the. Injected contrast medium is more prominent in 100K people protocol, probably 'cause we gave original concentration on contrast medium. So to summarize this Part, 70 KB protocol with 60% contrast, medium dosage provide greater enhancement then 100 KB protocol and also it show identical contest to noise ratio and unfortunately the beam had artifact more prominent in septic. Every protocol at the level of the pelvis and shoulder however. This protocol show less streak artifact from the injected contrast medium at the level of brachial vein. So there several way to reduce the total amount of contrast medium. First, we can reduce the injection rate using the original concentration or contrast medium, and then with maintaining same duration of injection. Or we can dilute the contrast medium with maintaining both injection rate and injection duration. And also we can reduce the total time of injected duration. However, if we apply this technique. We should change the delay timing so it is really confusing. So in order to investigate our profit method to reduce either deliver rate. We compare these two protocol for context injection. Reducing injection rate using original concentration on contrast medium or using diluted contrast medium with maintaining injection rate. Anna's here. The degree of contrast enhancement was similar in the doors of technique because we gave the same amount of contrast medium. However. I'm sorry once again before the vessel enhancement once again, there are no signal difference between these two group, however. For Brackettville once again. When we give the original concentration or contrast medium with reduce injection rate, we still have much higher concentration as city value of Virgil van with this technique. And it can cause severe streak artifact in the from the contrast medium in the breakaway. Therefore. When we reduce the total amount of contrast medium for locate the city, we should dilute contrast medium with maintaining injection rate and injection duration. Please do not give inject give us lower injection. So accordingly we set the our routing protocol for Body contacted City. Well Fortunately or Fortunately we have four city scan and an only once to Martin Force. We applied first come first serves policy. So he basic come to Domino falls. We perform 70 cabbage scan with reducing contrast media. We using diluted contrast medium. And the web patient comes to another scanners, we perform 150 KBP with standard contrast medium dosage. But I have one more thing to mention. This table summarizes our one year data of Continent City, approximately 1 six of all content handheld scanner in our institution were performed with 70KV protocol using low contrast dose. An when we rebuild. Our adverse event record for one years. An this table summarizes the number of allergic reaction and physical reaction occurs in the patient with 70K baby roles, protocol and standard. Those protocol. And we found that the incident a radically react reaction and theoretical reaction in low contrast Meadows protocol were significantly lower than those of a standard dose protocols. So in conclusion. 70 can be protocol would be sufficient for Japanese or even Asian population in routine contrast enhance body city study with reduced contrast, medium and radiation dose. In order to reduce the either deliver rate for low capacity. Contrast medium should be diluted. Free to not reduce the injection rate. And although we need further study by the role capacity with reduced contrast, medium may decrease the incidence of acute adverse events. So yet I recognize all the all our City team in at home by University and also adopted press my sincere appreciation to zoom in healthcare for key providing scientists and clinical support and also thank you very much for your kind attention.

13th SOMATOM Worl • • Today's topic Background of low kV CT 70 kVp vs. 120 kVp protocol How to reduce CM dose One more thing..... One more thing.... Köbe University Hospital, Policy at Kobe University Hospital 7() k Vp vs. 120 kVp protocol Overview Of CT exam at Kobe Univ. Hospital Low kVp CT angiography BackgroundÆ)f low kV CT 70 k Vp vs. 120 kVp protocol Kobe University Hospital, Conclusion Overview of CT exam at Kobe Univ. Hospital 70) kVp vs. 120 kVp protocol 6. Clinical Validity study Low energy CT in Vascular imaging Any further benefit in low kVp CE study? Take Home Message Drawbacks of low energy CT Compare historical data at SOMATOM Force How to reduce CM dosage Reducing injection rate or CM dilution? Low energy CT Daily clinical practice at Kobe Univ. Hospital CE+ exam @ SOMATOM force Protocol selection in our institution Adverse effects report sli e slice Body weight CTDlv01 CM With lowering tube voltage, the effective energy of the X- I ,699 exams with low CM protocol at 70 kVp Vessel enhancement Artifacts Greater enhancement 2 month period Beam hardening artifact For routine body CECT (thoracoabdominal or abdominal) Quantitative analysis (HU) To investigate appropriate method to reduce IDR Short summary 3rd generation DSCT was installed in Jan. 2015 Contrast-to-Noise ratio Relative incident photons decrease at low energy 015 Abdominal organ enhancement 70 kVp protocol would be sufficient for Japanese 70 kVp (270 mgl/kg BW) 120 kVp (450 mgl/kg BW) p=.ll Beam hardening 70 kVp routine+pre Ope 120 kVp 70 kVp 70kV 100 80 70 120 120 Duration Allergy-like reaction Physiologic reaction Satoru Takahashi p<.0001 CM to approximately ray beam will be closer to the K-edge of iodine (33 keV), 70 kVp 120 kVp CT angiography P<.0001 2150 250 12,144 exams with standard dose protocol at 1 20 kVp injection rate Reduce injection rate so TOM Fo 70 kVp 120 kVp 70k 70kV 70 kVp great vessels 120 kVp great vessels less population in routine contrast enhanced body CT study p=.196 p=.19 Acquilion ONE SOMATOM Force Organs SIEMENS .. Vessel Reduced injection rate using original concentration of CM Reduced Injection rate Beam hardening artifact Acquilion 64 p<.0001 p=.0061 Satoru Takahashi 50 70 120 wp O mgl/ SIEMENS 70 kVp 120 kVp Sever kVp 15 40 200 25 250 45 70 wp 70 kVp To compensate sufficient 70 kVp protocol with 60% CM dose provides CM injection with "Dual head" Power injector First come, first serve Routine post-contrast body CT (thorax to pelvis) at with 90 mL of CM _SmaILpeJyis Small pelvis 6,609 CT exam p<.0001 p=.196 with 70 Reduced injection rate Köbe University Hospital, Degrees of organ enhancement were not influenced 70 kVp cardiac 720 kVp protocol 120 kVp protocol low dose standard dose 120 Wp Standard than those of standard dose protocol. 120 kVp — 120 kVp 57% 86 8% 80 y, low trast do e trast do e Reduce injection rate 1,575 with reduced CM and radiation dose Severe Diluted CM 250 — 120 kVp protocols become Köbe University Hospital, Abdominal aorta 90 120 Wp 70 Wp p<.0001 70 kVp 120 kVp 720 kVp Diluted CM Shoulder, Small pelvis pelvis 70 kVp 120 kVp 720 kVp 120 kVp Using diluted CM with maintaining injection rate 834 thing 120 120 kVp with standard dose of CM n=103 photons for maintaining One with the concentration of CM, when IDR were identical 70 kVp CT with 60% dose of CM 200 Urticaria / Pruritis 32 107 3% Diluted CM p value Köbe, Japan 50 57% more • 5.5 mgl/mL c uilion 64 Il mgl/mL 40 80 SOMATOM Force At SOMATOM Force Greater enhancement low-dose standard-dose 70 kVp 120 kVp 70 Wp 70 kVp — 120 kVp 120 Wp time 720 kVp protocol 120 kVp protocol HeaLthineers Healthineers Portal vein CT in practice ractice image quality, large To reduce iodine delivery rate for low-kVp contrast 120 kVp routine 120 kVp protocol K-edge Cutaneous edema Metallic object 3% Acknou Reduce injection rate Reduced injection rate Diluted CM No of unique patients Since late Jan. 2015, started low-dose protocol at 20 vp low-dose 120 kVp CT with a standard dose of CM p-.90 p=.196 p-.006 p-.9001 Moderat Moderate 120 I kVp CT wit a standard dose ,983 Reduced injection rate with original concentration of p-.18 18 Reduced rate Tube current Lesion quality ref 170 mAs (thorax), 200 mAs (andomen p=.49 p-.09 p=.42 p-.42 "Scratchy" throat tube current is essential 41 Altered taste enhanced CT, concentration of CM should be diluted, 270 mgl/kgBW 1 20 kVp 70 kVp Amount Low energy, Lou p<.OOOl Identical CNR to 120 kVp protocol scan with reducing CM dose using diluted CM 1 ,575 exam 1,575 exam 30 70 Moderate 14% p<.0001 150 11 10 Standard-dose 100 838 4,324 Shoulder p<.OOOl _p<.0001 70 kVp with CM 70 kVp with 600/0 CM n=100 CM caused much greater CT values of the brachial vein, CT simu p<.0001 p-.0042 p=.006 p-.004 p=.094 Nasal congestion Vasovagal reaction Germany 2017 57% 01 p=.35 p=.195 Jan.2015 to Feb. 2016 instead of reducing injection rate. Acquilion 64E Acquilion ONE cquilion ONE CARE Dose4D CARE Dose4D 180 mgI/mL 50 40 100 20 45 3% 250 20 2,842 Dose reduction Concentration leading to severer streak artifact 300 - 370 mgl/mL 96 86 Dual Energy routine Sneezing More prominent beam-hardening artifact at the level At remaining CT scanners 81 2 CE+ exam CARE kV (Semi) diluted with saline contrast dose CT in 80 1,575 50 30 p=.19 p=.49 p=.42 Diluted CM 70 kVp 70 W 70kV Total 1,421 Mil Mild Cough Low-kVp CT with reduced CM may decrease the incidence p=.45 Acquilion 6 Acquilion ONE of the small pelvis & the shoulder p<.0001 Mild Collimation 192 x 0.6 mm Kobe Köbe University Hospital, at Kob un versity o niversity Ho ital To reduce IDR for low-kV contrast enhanced CT, adjusted for fix duration Rate CM 120 kVp with standard CM dose 66.4±13.1 Great our CT team at Kobe University 41 Dual Energy lung perfusion 100 of acute adverse events 10 1,37 Subject of my talk should be diluted, instead of reducing injection rate Dyspnea Less streak artifact from injected CM 63.8±15.8 66.4±13.1 63.8±15.9 0.5 sec/rotation Hospital The statements by Siemens Healthineers• customers described herein are based on results that were achieved in the customer's Duration 45 sec 1 20 kVp 120 Wp p=.35 Reduced duration Hypotension No artifact 0-95 Age range 80 70 120 100 11 250 @ÖOmgl/mL, 50 mL, 1.1 PLIsÄNQmg/mL, 81 @ÖOmgJ/mL, 50 mL, 1.1 DIJ-sÄNQmg/mL, 81 mL,Aß-mtfs Slice thickness 1.1yLLsÄNOQmL, 81 mL,A8-mtfs Brachial v. SIEMENS .. SIEMENS ... NO artifact Scan delay time thorax, 50 sec; abdomen, 1 00 sec thorax, '00mgVmL, 5 0 m L, 1 . 1 Total 250 100 40 200 140 100 Kidney 324 Renal cyst svc April 1 May 31, 2017 April I May 31, Spleen 115 70 2017 10 40 Liver 80 120 '40 Liver Mets. Small pelvis Metal 70 kVp 120 kVp l/mL, WW/W /mL, 81 / L, 81 Tube-voltage (kVp) 120 vp 50 50/ Shoulder 1.1 Brachial v. 120 kVp 70 kVp 120 kVp 70 Wp 120 kVp 120 Wp 120 wp 70 kVp 4-94 o - 99 10 Total Allergy-like Physiologic kVp Pancreas Energy (keV) Portal v. Brachial v. Healthineers Aorta Photon Energy (keV)