Interventional ultrasound in obstetrics dr rabi
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Transcript of Interventional ultrasound in obstetrics dr rabi
INTERVENTIONAL INTERVENTIONAL ULTRASOUNDULTRASOUND
DR. RABI NARAYAN SATAPATHY
ASST.PROFESSOR
DEPT. OF OBST.& GYNAECOLOGY
SCB MEDICAL COLLEGE, CUTTACK
MOB-09861281510
ULTRASOUND GUIDANCEULTRASOUND GUIDANCE
TRICKS AND TIPSTRICKS AND TIPS
GENESIS SCANS ULTRASOUND TRAINING CENTER
PROCEDURES
• AMNIOCENTESIS-diagnostic / therapeutic
• C V S
• CORDOCENTESIS-sampling / transfusion
• BIOPSY- fetal skin / liver
• SHUNTS-vesicoamniotic / thoracoamniotic
• FETOSCOPY -usg guided
• FETAL GENE Rx- stem cell transplants
PRINCIPLES
• AMNIOCENTESIS
• C V S
• CORDOCENTESIS
• BASICS ARE THE SAME
PLANE OF BEAM - tips
• Varies with different transducers
• Unusual to be in precise middle of Tz.
• Identify the ‘sweet spot’
• 22g and above needles bend ( get rigid 22)
• Use PHANTOM to practise ( Jar of GEL)
• Optimize machine setting
FREE HAND TECHNIQUE
• PERPENDICULAR OFFSET ( 90º ) needle too far away
• PARALLEL or SIDE ON only needle tip is visualized
• END ON APPROACH ( 45º) variable angle / probe can be rocked
targetSEEN - targetNEEDLED
• SONOENHANCED needles ( ??)
• STERILE ZONE -double glove, shroud
• LOCAL ANAESTHETIC (amnio??) initial marker for needle path
• ANTIBIOTICS ( for high risk cases)
• COLOUR DOPPLER
• DETAILED INFORMED CONSENT
TECHNIQUE
• Proper planning
• Good equipment
• Operator skill
• CONTINUOUS NEEDLE VISUALISATION IS A MUST.
TECHNIQUE
• Single main operator ( + assistant)
• Two operators ( sonologist + operator)
• ONE CEREBELLUM IS BETTER THAN TWO FOR CO-ORDINATION.
ARTEFACTS
• NEAR FIELD BACKSCATTER REVERBERATION( ? Anterior Placenta)
• RING DOWN (Comet tail)- Needle Tip
• REFRACTION & MIRROR IMAGE (Wrong location)
• BEAM THICKNESS- Needle position.
Coelocentesis• Between 6 -12 weeks
• Advantage of early Prenatal diagnosis(< 10w)
• 95% success rate bet 7 - 10weeks
• Low rate of contamination by maternal cells.
Coelocentesis
• Early amnio and CVS not performed before 10weeks
• Less traumatic to embryo & placenta
• Fetal loss = 0r < that in early amnio.
Coelocentesis• Biochem. different from early Amniotic
fluid and maternal serum.
• Study materno-fetal exchange when FBS cannot be obtained.
• Prenatal diagnosis of chromosomal and genetic disorders.
Coelocentesis-Procedure
• EVS + Needle guide + 20g needle
• Through “Anterior ut.wall”
• Needle / /el to amniotic membrane.
• Needle afaap from YS and Amn.membrane
Coelocentesis-Procedure
• Low pressure aspiration.
• Continuous monitoring of needle.
• Yellow coloured and more viscous than Amniotic fluid (always clear)
Coelocentesis
• 5 to 6 ml volume by 9weeks
• 1 to 2.5ml required for diagnostic purpose.
• 90% of cells are viable (before 7weeks)
• Cells : mostly of haemotopoietic origin.
Coelocentesis (vs)
Placental DNA
• Complete concordance in results for
• (1) Diagnosis of single gene disorders (sickle cell)
• (2) PCR with Y centromeric primers for Sex prediction ( 100%)
Coelocentesis
• Easy to learn, new invasive approach to prenatal diagnosis.
• Using FISH probes it appears Karyotyping is possible at 6weeks gestation.
• Further work is necessary to improve culture success later in gestation
Umbilical cord catheterization
• Fetal blood exchange transfusions
• < 5mins procedure
• Catheter in vein for 30 - 210 mins
Umbilical cord catheterization
• No haematomas within Wharton’s jelly
• No chorioamnionitis.
• Nutrient supplementation / Gene therapy/ treatment of fetal pain and infection.
Tracheal Ligation in CDH
• Purposeful occlusion of the fetal airway results in lung growth avoiding pulmonary hypoplasia, which is the main complication in fetuses with CDH.
• The hernia is then repaired after birth
Tracheal ligation - exclusion criteria
• Unwilling patient
• Presence of major congenital anomalies
• Abnormal karyotype
• Ruptured membranes
• Chorioamnionitis • Diagnosis made after 25 weeks gestation
EXIT- ex utero intrapartum treatment
What is an Amniopatch?
• ONE unit of maternal blood.
• Blood Bank obtains platelets and cryoprecipitate (cryo) in 2 days
• USG guided injection of these into amniotic cavity takes only a few minutes.
Amniopatch
• Platelets activate the clotting mechanism and the cryo acts like a cement to hold the platelets in place.
• It can take 2 weeks for the membrane to reattach.