Medical Physical Imaging
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X Ray Ultrasound CT Scan Nuclear Medicine Nucle Endoscopy Imaging Source X Ray (outside) Ultrasound waves (Outside) X-Rays (outside) Gamma Ray from Radioisotopes (inside) Light source from outside guided into the body(non- bundled fibre) Physis and concept Attenuation and transmission of X ray , exposure of film Reflection at boundaries with different acoustic impedance Attenuation and transmission of X ray , Collected by a number of sensor and computer processing Radioactive decay, radioactive half life and biological half life, gamma rate imaged by senor Total internal reflection, refraction Remark Gel to reduce loss at air/skin interface Nuclear Cow produces Technicium Advantages Low Cost(100) Not/ invasive Low cost(500) Non-invasive, safe No radiation used(good for fetus examination) Real Time movement of organ -easily Speed Can scan images for bone and Cartilage Non-invasive -form 3D image -Functional organ visualization- (kidney) -Help define space occupied bu tumor - Non-ionizing, see texture and colour- direct observation, can do biopsy/tissue sample at the same time, no need to make large surgical cut to look inside;
description
Comparing X Ray Ultrasound CT Scan Nuclear MedicineNucle Endoscopy at 2nd schhol level
Transcript of Medical Physical Imaging
X Ray Ultrasound CT Scan Nuclear MedicineNucle
Endoscopy
Imaging Source
X Ray (outside) Ultrasound waves (Outside)
X-Rays(outside)
Gamma Ray from Radioisotopes (inside)
Light source from outside guided into the body(non-bundled fibre)
Physis and concept
Attenuation and transmission of X ray , exposure of film
Reflection at boundaries with different acoustic impedance
Attenuation and transmission of X ray , Collected by a number of sensor and computer processing
Radioactive decay, radioactive half life and biological half life, gamma rate imaged by senor
Total internal reflection, refraction
Remark Gel to reduce loss at air/skin interface
Nuclear Cow produces Technicium
Advantages Low Cost(100)Not/ invasive
Low cost(500)Non-invasive, safeNo radiation used(good for fetus examination)Real Time movement of organ-easily accessible/portable- comfortable to patient/no pain
SpeedCan scan images for bone and CartilageNon-invasive-form 3D image
-Functional organ visualization-(kidney)-Help define space occupied bu tumor-
Non-ionizing, see texture and colour-direct observation, can do biopsy/tissue sample at the same time, no need to make large surgical cut to look inside;
Drawback Do not image all organ and tissue well (good for lung, bad for-ionizing- not behind bones
Cannot see area around lung(air inside reflects ultrasound)/behind bones/behind air filled organs(bowel)-image not clear-small field of vision vs CT
High CostIonizing radiation(higher dosage than X-Ray)
Poor Anatomical DefinitionSignificant ionizing radiation dosage
Invasive-May cause infection/complication, perforation, longer time,need anaesthesia/fasting-only for area with natural opening to outside or need incision(walls of cavity, hollow organs)-can see surface only, small field of vision
Good for Bones fetus Brain tumor Kidney function Stomach, Colon, Cannot be used for
Image behind bone (=> not for brain or organ behind bones)
Cannot see beyond air filled space(most sound energy reflected at tisse/air boundary backwards)
Inside brain or inside solid tissue(liver)
Common use Broken Bones/chest/TB/Cancer/dental
Fetus(=>non-ionizing)Heart- real time, soft tissue among soft tissueKidney(water filled cf lung – gas filled, large intestine)
-blood clot-Brain(=Xray not good resolution, ultrasound cannot penetrate)-emergency room(quick full imaging)
-Kideny-Adominal region-brain
Colon cancer screening
Invasive – possible infection
