Target (TIFFA scan) in Vijayawada

Being pregnant is a beautiful experience that nothing else can match up to. Your pregnancy will be loaded up with various emotions. You could have weird cravings, the pregnancy glow that everybody talks about, nausea as well, in some cases, yet one constant all through this amazing journey will be the intense care you will feel for your unborn baby. TIFFA stands for targeted Imaging for Fetal Anomalies. As the name says, this scan is performed to understand if the baby is developing fine. TIFFA scan in Vijayawada is performed between 18 and 23 weeks of gestation.

How is the target scan done?

TARGET scan is done transabdominally. The sonologist will initially apply the gel to your belly. The probe is then moved around the region to be studied with a hand held probe.

Uterus is surveyed to localize the placenta, check amount of fluid around the baby(liquor), fetal movements and cardiac activity of the fetus. Following this, weight of the baby is assessed by measuring femur length, abdominal circumference and head circumference.

Later on, each organ is imaged as per guidelines of fetal medicine societies to detect anomalies if any.

On the ultrasound screen, you will see images of the baby in grey, black and white shades. To acquire clear photographs of your baby, the sonologist may apply slight pressure to your abdomen while repositioning the probe.

1. The total procedure lasts for about 20 minutes. However, it very well might be delayed if your child moves a lot or on the other hand a sonologist can't check any region of the baby in detail owing to the baby's posture.
2. The sonologist might ask you to wait some additional time till the baby shows the right position or may call you back one more day to inspect it.

Importance of TIFFA scan:

Incidence of major congenital anomalies is around 2-4%, contributing to 30% of perinatal mortality. Congenital anomalies could be caused due to genetic, environmental factors or both. Frequency of chromosomal abnormalities depends on the type of anomaly and number of anomalies.

Central nervous system anomalies ( Anencephaly, open neural tube defect. ) are the most common ones found in India, followed by cardiothoracic , musculoskeletal , genitourinary and gastro intestinal systems.

Main aim of performing a TIFFA scan is to ensure structural normalcy of the baby and to detect major /lethal anomaly when it is legal to terminate the pregnancy.

Anomalies are categorised as

1. Lethal
2. Major but non lethal
3. Minor anomalies.

Abnormal TIFFA - what next?

What to do next depends on legal gestational age for medical termination of pregnancy, gestational age at which TIFFA is done, ability to visualize anomalies at that period of gestation and available time for counselling and further investigation.

Additional ultrasound tests may be required to detect if abnormalities are present in other organ systems .These tests include fetal echocardiogram, fetal neurosonogram, fetal MRI.

Clinical examination and ultrasound evaluation of parents may be required when certain type of anomalies are detected in the fetus. Ex: Polycystic kidney disease , rhabdomyoma , congenital heart block.

If this is a recurrence of anomaly, past obstetric history and genetic tests have to be reviewed.

Sequence of events that usually take place after detecting an anomaly are

1. Counselling:
2. Prenatal diagnostic test
3. Follow up
4. Postnatal management
5. Perinatal autopsy
6. Pre-pregnancy counselling

Counselling is done to help couples make informed decisions consistent with their own goals and values.

Prenatal diagnosis can be done by various of genetic tests like FISH, karyotype, microarray, exome sequencing. Accurate diagnosis is important for assessing the prognosis of the baby, planning for specific needs at birth, understand treatment options before and after birth, improve neonatal survival, predict recurrence risk and discuss reproductive options for subsequent pregnancy.

After counselling, if the couple opts to get prenatal invasive diagnosis and the report shows aneuploidy in the fetus, they can go for medical termination of pregnancy and perinatal autopsy. If the fetal karyotype is normal and the abnormality can be treated after birth, they will be referred to the concerned speciality doctor eg. Peadiatric surgeon for counselling regarding the treatment options for the abnormality and its outcome.

After counselling, if the couple declines prenatal invasive diagnosis and decide to terminate the pregnancy, they are advised to store DNA of the fetus and get perinatal autopsy. If the couple decide to continue the pregnancy , they are referred to concerned speciality.

Counselling with the concerned speciality doctor helps the couple to make informed decision on continuing the pregnancy, plan the place of delivery. Few conditions might require delivery in a tertiary care center with neonatal intensive care unit with ventilatory support and peadiatric surgery facilities.

Perinatal autopsy is the postmortem examination of the aborted fetus or still born baby to confirm the diagnosis made on ultrasound and to identify additional defects that were missed on ultrasound due to various reasons like less visibility of organs because of less liquor, unfavourable fetal position or the ultrasound resolution was inadequate to detect the anomaly.

It has been found that in perinatal autopsy, additional information was found in around 25% of cases and prenatal diagnosis was revised in around 5% of cases.

LIMITATIONS OF TIFFA SCAN:

Detailed examination of the fetal parts may be compromised if

1. The fluid around the baby is less
2. Mother is obese
3. There are multiple fibroids in the uterus
4. There are scars on the uterus due to surgeries on uterus in the past
5. Scan is performed at a time when the particular organ hasn't completely formed
6. Fetus is in unfavourable position during the time of scan (facial structures cannot be seen clearly if the fetus is lying on its face with its back facing upwards)
7. There are few anomalies which might evolve as the baby grows and they can be seen only late in gestation.eg; ventriculomegaly, bowel dilatation, pelviectasis, cyst in the abdomen.
8. Detection rate is low for anomalies like esophageal atresia.

SOFT MARKERS:

Soft markers are ultrasound findings seen during TIFFA scan. They are widely regarded as normal variants commonly seen and are known to resolve as the pregnancy advances. They are not structural abnormalities and do not hamper the function of the baby.

However, few soft markers could have association with chromosomal and non chromosomal abnormalities.

Interpretation of Soft markers requires correlation with maternal age and serum test for aneuploidy results.

Each soft marker has been assigned a likelihood ratio which indicates its strength of its association with chromosomal abnormalitiy.

Fetal medicine consultant will review all these details and suggest appropriate plan of management.

IMPORTANT NOTE TO EXPECTANT PARENTS:

It is important that the expecting parents understand the fact that completion of scanning the fetus depends on the position of the fetus. Examination of the face and heart requires the fetus to lie on its back (supine position).Examination of spine requires fetus to lie on its face.(prone position).

At Bhishak fetal medicine center, best fetal medicine specialist in Vijayawada would review the scan after 2-3 hrs on the same day if the fetus is not in favourable position to scan particular part. If the fetus is persistently in the same position, we would review the next day after a couple of days.

Consult Dr. P. Madhavi Latha at gynecology hospital in Vijayawada