9 3D Flashcards
Why do we do 3D
Nose/lips (clefting) NTD hand/feet/ankles Heart - 4CH only view needed, VSD? Gynecology-EV in endo Mullerian duct abnormalities Endometrium IUDS
4 Different methods. Method 1 is?
Free hand 2D (curvilinear)
We manually do the sweep.
No measurements but no extra equip required.
Method 2
Used separate transmitter. attached to outside of 2D creates electromagnetic field
Method 3
Mechanical 3D/4D transducers
used motor, steered electronically, sweeps in fanlinke motion.
Bulky and heavy
Method 4
3D/4D matrix transducers
cardiac applications and more crystals
ROI means
Region of interest. (can adjust)
MPR means?
Multiplanar Reconstruction
Pixels are?
smallest unit of 2D image
Voxel is?
the smallest unit of a 3D volume set
X =
Y=
Z=
Width of sweep
Height
Volume of the slice you’re taking (distance transducer covers in a sweep)
For fetal heart you want a ___ volume angle
small
For a Uterus ___volume angle
large
Acquisition speed -Slow means?
More slices
Better quality volume
Higher resolution
Acquisition speed -Fast means?
Active fetus
Eliminates fetal motion
Poor image on 2D means?
POOR 3D
Factors affecting image quality
Maternal size
Decreased amniotic fluid
Fetal postion
3D multiplaner reconstrction 3 planes and forms volume.
explain X, Y , Z?
A/X, = Sagittal B/Y = transverse C/Z= Coronal
Which planes determine ROI?
A/X, = Sagittal B/Y = transverse
Which place determines volume size?
C/Z= Coronal
What has the lowest resolution ? Order of lowest to highest
- C/Z= Coronal - lowest
B/Y = transverse
A/X, = Sagittal
The red dot application on EV
put in endo tissue in 3 planes
to look at endo
Virtual rescan not limited to these 3 images .
Describe (4)
a multitude of images maybe reconstructed
can rotate images in any axis
can sweep through each plane
similar to repositioning transducer
What is Tomographic US? (4)
similar to CT and MRI
Multislice
Doppler and Power Doppler can be used
More uniform protocols similar to our other modalities
What is Rendering Modes?
Different algorithms used to display 3D data on screen
Look at bone (skull) or soft tissue
What are the 3 surface rendering settings?
- Surface Smooth
- Surface texture
- Gradient light
What is Surface smooth?
gives face smooth surface or skin. no underlying structures are displayed
What is surface texture?
enhances details of a surface
What is gradient light?
illuminating giving depth impression- more live like
Electronic eraser is?
removes unwanted structures from image, placenta from face, uterine wall
X ray mode/Max skeletal
eliminates weaker signals like ST visualize bone (stronger signal) Why? some syndromes have wormian bones (downs, and skeletal dysplasia)
Inversion
hypoechoic structure turned into solid structure
a digital cast.
grey scale removed
cystic area visualized as an echogenic area
Inversion technique with Obstetrical used with
Fetal ventricles
Dilated fetal urinary tract
Heart and vessels
Fetal stomach
Inversion technique with Gynecology used with
Saline filled UT - sonohysterography
PCOS
Hydrosalpinx
Follicle monitoring
Glass body or Transparency is used in conjunction with?
Color doppler
Glass body or Transparency is tissue transparent and allows one to see ___better
vessels.
Grey scale completely removed
VOCAL stands for?
Virtual Organ Computer Aided Analysis
How does VOCAL SOFTWARE work?
measures volume or an irregular object. Maps it, rotated 180 around a fixed central axis and creates 3D model
What is the difference between 3D vs 4D
4D is just 3D live real time.
3D = static, single sweep, volume stored and viewed
Why use 3D/4D in Gyne?(6)
Congenital Ut abnormalities IUCD location - perforation? Endometrial lesions - ashermans, polyps, fibroids Origin or adnexal masses Sonohysterography Infertility evaluations
Bicornuate Ut
“bunny ears”
2 Uterus. Indentation >1 cm
(maybe us 2 IUCDs)
Subseptate Vs Septate
Septate- all the way through, 2 endo canals, 1 Ut
Subseptae - >1 cm, not all way through Cx
Arcuate Uterus is?
< 1cm indentation in fundus
An Endo restriction is?
<5mm are hard to see
Z technique is used for?
coronal Uterus
Spine in multiple plane to look for?
Spina Bifida
Hemivertibrae
AIUM states?
discourages the use of US for reasons not medically indicated
