Maureen McDaniel, MEd, RDMS, RDCS, RVT Sagittal Coronal Transverse - PDF document

Maureen McDaniel, MEd, RDMS, RDCS, RVT

� Sagittal � Coronal � Transverse

� Also called multiplaner, surface rendering, volume scanning � Originated about 25 years ago � More widely available 1990’s

� Get the middle point in the picture in 2D � For face this is the profile � Angle transducer all the way to side � Want to start in amniotic fluid � Move smoothly through anatomy till you reach other side � Hopefully ending in amniotic fluid � The machine then calculates volume, based on the 2D images obtained

� After you have the quad screen � Cut off surrounding objects � Adjust transparency for desired effect

� Tissue Heating � Cavitation � Gas bubbles developing within tissues due to prolonged exposure. � Caviation effects are possible within range used for diagnostic examination � Transient cavitation � Bursting of bubbles causing cellular damage � Rise in temperature of 2 ⁰ C

� AIUM clearly discourages US for fun � Scanning for parents increases scan time � AIUM prohibits videotaping because it lengthens scan time � What are we gaining? � Extra charge for insurance companies � Must be ordered by perinatologist—not OB

3 D Technology Approved October 1999 Currently, two-dimensional (2D) gray-scale real-time sonography is the primary method of medically indicated anatomic imaging with ultrasound. While three-dimensional (3D) sonography may be helpful in diagnosis, it should not be considered more than a developing technology. Its role is restricted to an adjunct of, but not a replacement for, 2D ultrasound. As with any developing technology, its diagnostic value may improve, and its diagnostic role will be periodically re-evaluated .

The new position statement is as follows: The AIUM advocates the responsible use of diagnostic ultrasound for all fetal imaging. The AIUM understands the growing pressures from patients for the performance of ultrasound examinations for bonding and reassurance purposes largely driven by the improving image quality of 3D sonography and by more widely available information about these advances. Although there is only preliminary scientific evidence that 3D sonography has a positive impact on parental--fetal bonding , the AIUM recognizes that many parents may pursue scanning for this purpose.

� As Low As Reasonably Achievable � Benefits must outweigh the risks � Only when medically indicated � Determining gender is not medically indicated unless risk of x-linked disease

� Maternal body habitus!!!!! � Not enough amniotic fluid � Face looking down � Face looking up but into or against placenta � Arms or legs in front of face � If scanning extremities, almost always have problems with surrounding structures � Only a problem for 3D, not 4D � Fetal movement � Sonographer not keeping steady movement across structure

ooh, aah

Anyone? Color

Face looking into placenta

scary

Even scarier

I’m an alien

� OB � Cleft lip and palate � Usually ordered after previously seen in 2D

� Central nervous system anomaly

3D image 2D images

2D image 3D images

� Polycystic ovaries � Uterine anomalies

� Severity of ventricular septal defect � Mitral valve regurge � Mitral valve repair � Problems with movement

� Vein of Galen aneurysms � Periventricular leukomalacia � Ventriculomegally � Holoprosencephaly � Circle of Willis

2D images of ventriculomegaly and periventricular leukomalacia 3D imaging of same infant

Breast tumor with power angio

� Echotexture � cystic or solid; homogeneous or heterogeneous � Shape � taller than wide � Shadowing � bilateral or unilateral

� Higher accuracy for staging esophageal, gastric, colo-rectal cancer � Used to show effects of chemo/radiation therapy � Follow up for early detection of recurrences after tumor resection

2D image of lining of GI tract

� If non-moving object, can acquire all three planes in time it takes to acquire one � Physician can manipulate images later if proper recording techniques are used � Procedures

� Movement of object or sonographer � Operator dependent � Physician may take longer to read study

� Fine needle biopsies � Ethanol ablation � RF ablation � Cryoablation � Catheter placement for drainage

� Adds time as a forth dimension � Place probe. � Mechanics inside move angle for you. � Very large probe � Less room for operator error � Same constraints as 3D � Need amniotic fluid, fetal position � Great for real-time procedures

� Most sonographers retire due to MSI � Carpel tunnel

� 4D is coined by GE � Live 3D used by other manufacturers � ATL (now Philips) had live 3D before GE introduced 4D � Marketed to public rather than Doctors and Sonographers—why? � Why marketed for OB instead of other modalities? � Similar to Pharmaceuticals � Is this marketing to public effective?