PENGENALAN ALAT CT SCAN

1. CT-SCAN
Sumarsono,Dipl.Rad,S.Si
sumarsono75@gmail.com

2. What is CT Scan ?………….What is CT Scan ?………….

3. Radiographic imaging
Computed Tomographic
imaging
Conventional Radiography Conventional Tomography

4. Examination Table
Gantry
Operator Console
Injector Controller

5. Definisi
Computed tomography (CT), biasa pula disebut
computed axial tomography (CAT or CT scan)
maupun body section roentgenography, adalah
suatu teknik pencitraan medis untuk
menvisualisasikan secara irisan (tomografi)
jaringan atau organ tubuh yang diperoleh melalui
rekonstruksi komputer dari proses digitisasi sinar-x
yang bergerak mengitari objek pemeriksaan

7. Blok Diagram pesawat CT-Scan
X-Ray Tube
De t e c t o r
Pre Amplifier A /D
Comverter
C O MPU T E R
Sistemmemory
(DISC/Digital Cassete)
Line Printer
CRT Display
G
A
N
T
R
Y
Hard Copy

9. CT- invention

10. Dr. Godfrey Newbold Hounsfield
- Born in 1919 in Nottinghamshire, England.
- Graduated from Radar school at Royal Air
Force in Cranwell.
- Graduated from Electrical & Machanical
Engineering from Faraday House.
- In 1951 joined EMI Limited company
- In 1967 was studying the images reconstruction
technique and images processing by using the
computer.
- In 1971 the first clinical prototype brain scanner
was installed at Atkinson-Morley’s Hospital.
- In 1972 the first patient was scanned by this
machine. The images showed clearly in detail a
dark circular cyst in the brain.
The inventor of clinical CT

11. - In 1971, CT prototype was installed at
Atkinson-Morley Hospital.
(processing time ~ 20 minutes)
- Processing time was reduced to 4.5 minutes
by changing to used minicomputer.
- In 1972, the first patient was scanned by this
machine.
- Head scan only.
- CT images showed clearly detail a dark circular
cyst in the brain.
First-generation CT head scanner(EMI):
Water bag
Tube
Single detector

12. Evolution of CT

13. Evolution of term :
Computed Tomography has held many names
- Computerized Transverse Axial Tomography ( CTAT)
- Computerized Axial Tomography (CAT)
- Reconstructive Tomography (RT)
The term as most commonly being used to day
is Computed Tomography (CT).

14. • 1971 First Generation
• 1972 Second Generation
• 1975 - Present Third Generation
• 1977 - Present Fourth Generation
1983 Fifth Generation
( Imatron developed )
GENERATION OF CT SCANNERS

15. First Generation
Translate/Rotate with Single Detector
With single detectorcan only
acquire one view at a time
Mechanically complex
Long scan times (4-5 minutes).
VERY SLOW!!!
Problems …..

17. Second Generation
Translate/Rotate with Multiple Detectors
An improvement over the 1st Generation
Problem...
Mechanically
Complex
Improvement...
Multiple detectors
(up to 30 detectors)
allowed fast scanning
( 20-90 Seconds)

19. Third Generation
Rotate / Rotate
Problem...
Faster scan time
still need for
clinical use.
( 4.9 sec. / 1975)
Improvement...
- Array of detectors and tube
rotate around the patient for
faster scanning.
- High mechanical stability.
- Good tube-patient-detectors
geometry.
- Detectors always in x-ray
beam, allow good utilization
of the x-ray beam.
Current Technology

21. Fourth Generation
Rotate-Only or Rotate-Stationary
Problems…...
- Due to the great number
of detectors be needed.
So……too expensive !!!
- More susceptible to
scatter radiation.
- Poor beam utilization
- Low detector geometric
efficiency.
X-ray tube moves within
fixed ring of detectors

24. Conventional CT vs Slip Ring CT
Step & Shoot Axial Axial & Helical/SpiralStep & Shoot Axial Axial & Helical/Spiral

25. Multi Slices CT Scanner
New Development of Spiral CT

26. Multi-Slice CT Scanners
Comparison the concept
of Single & Multi-Slice
Scanner.
Z - axis
Y - axis

27. X-ray Tube Focal Spot
X-ray Beam Collimator
16-row Mosaic Detector
Diode FET Switching Array
Flex ConnectorA Flex ConnectorB
Scaleable Multi-Slice X-Ray DetectionScaleable Multi-Slice X-Ray Detection
Detector Configurations
4 x 5 mm

29. Protocols with uncompromised Image Quality Dose Relative Exposure Time
Cardiac Helical 20-25 mSv* 100%
Cardiac Helical with ECG modulation 6-20 mSv* 50 - 81%
Cardiac SnapShot Pulse - prospective ECG gating 3-6 mSv* 25 – 30%
Diagnostic Cath 1-10 mSv
SnapShot Pulse: Average
Dose Comparable to that
of Diagnostic Cath
* Obtained by EUR-16262 EN, using a chest factor of 0.017*DLP
Dose References Dose
Chest radiographs – 2 views 0.08 mSv (5)
Mammogram 0.13 mSv (5)
Natural Background (Annual) 3 mSv (1,4)
Nuclear Tc-99m (rest only)
Tc-99m (rest+stress)
Tl-201 (rest+stress)
4 – 5 mSv (1,2)
9 – 13 mSv (1,2)
~34 mSv (1,2)
CT VCT Coronary Angio w/ ECG mod
VCT Calcium Scoring
6 – 15 mSv
~0.6 mSv
SnapShot Pulse: Dose Comparison

30. Clinical Applications, Cases & Images

31. Multi trauma Clinical CaseMulti trauma Clinical Case
Studies LS VCTStudies LS VCT

32. Case 1 : Head Trauma

33. Abdomen

34. Abdomen

35. Abdomen

36. Chest

37. CT AngiographyCT Angiography

38. What is CTA ?
CTA is thin slice helical scanning of vascular
examination to analysis the arteries and veins
using contrast media which non-invasive
method.

39. Indications of CTA :
• Aorta ; All lesions affecting the aorta orits wall, arc
anomaly,aneurysm, stenosis oclusion, arteritis, trauma
• Renal; Suspected stenosis
• Hepatic arteries; preoperative vascularanatomy, detection of
stenosis, occlusion afterlivertransplantation
• Carotid artery ; suspected stenosis, aneurysms
• Runoff vessels ; Peripheral arterial occlusive disease
• Pulmonary artery ; Pulmonary embolism, chronic
thromboembolic pulmonary hypertension, congenital anomalies
• Vena cava, portal vein ; Suspicion of thrombosis, tumor
invasion
• Post operative ; Complications : hemorrhage, infection, bypass
thrombosis, aneurysm

40. General suggested protocol for CTA :
• Preparation ; not necessary
• No contrast oral ornegative contrast agent ( water)
• Patient position ; supine
• Contrast : Non-ionic contrast 100-150 ml
• Acquisition technique : Scout – Pre Contrast – Contrast
• Post processing on the OC orAWWorkstation

49. AdvantageCTCAdvantageCTC

50. Why CTC ?
1. The examination on the complete length of the colon,
not limited to the distal colon only.
2. When need clinical evaluation of surface and deep colon structures,
such as diverticuli.
3. When need clinical evaluation of other part of abdominal structures,
such as liver, vascular structures, etc.
4. When the virtual dissection procedure were needed.
5. When the sedation being the issue.

51. CTC vs Colonoscopy
CTC
Less expensive.
Be considered as a screening study.
When diagnostic concern for both on the surface
and within deeper structures.
It is not only for CTC, but also for evaluation on
the liver, kidneys, pancreas as well as the other
retroperitoneal and pelvice structure including
vasculature.
Colonoscopy
More expensive.
For diagnostic + Therapeutic (biobsy).
For the surface structures mucosal tissue view.
It’s for colonoscopy only.

52. Case 01
70 years male, occlusive colorectal carcinoma
Can’t passed endoscopically, unable to vizualize colon proximal.
CT Colon technique:
- Bowel preparation
- Scanned in supine & prone
- Thickness 1.25 mm
- Took +/- 20 mnts (BS 8)
- Data sent to workstation, auto dissection, Navigator, 3D colon

53. Finding : Distal colon carcinoma (rectum)
3 polyps in right colon

54. 65 year old woman with transvere
colon carcinoma, 3 polyps detected
with CT colonography
Polyp 9 mm missed by conventional
endoscopy
Case 02 :

57. Navigator……..

58. CT PerfusionCT Perfusion

59. Allows quick calculation of Cerebral Blood Flow,
Cerebral Blood Volume, and Mean Transit Time.
Assessment of patients in minutes
Low contrast injection rates (approx. 4 cc per sec.)
CT Perfusion

60. DentascanDentascan

61. DentaScan
Real time image reformation specific to CT dental imaging :
• Obliques Perpendicular to the Dental Arch
• Panorex reformations.
Reformations can be :
• Cross-referenced in real time
• Saved on image database
• Printed on film.

62. CT CardiacCT Cardiac

63. What Cardiac CT is All About
1.1. Temporal ResolutionTemporal Resolution
2.2. Patient Breath Hold TimesPatient Breath Hold Times
3.3. mAsmAs
4.4. Spatial ResolutionSpatial Resolution
Stop Motion
Reduce Heart Rate variability During
Scan
Noise Reduction in Images
Detail Seen in Images
Everything Else is Superficial to These 4 FactorsEverything Else is Superficial to These 4 Factors

64. Why 5-Beat CardiacTM
is Critical
Heart Rate
Time
Beginning of
Breathhold
5 seconds
Heart rate increase
due to hypoxia
LightSpeed VCT
32 or 40 slice CT
5 sec scan covers entire heart during stable phase5 sec scan covers entire heart during stable phase
Chart Source: Dr. Nikolaou Universityof Munich, Germany– NASCI(NorthAmericanSocietyof CardiovascularImaging)

65. –

66. –

67. –

68. –
Why VCT ??Why VCT ??

69. The Ability to scan a heart in 5
heartbeats….

70. State of the Art Volume Viewer…..

71. Triple Rule-Out gated chest study in 10-
12sec….

72. 40mm COW/Perfusion Coverage……

73. Best CT Colonography package……

74. Terima Kasih
Pertanyaan???