1. Routine Anomaly Scan
Ilse Erasmus

2. Routine Anomaly Scan
Timing:
18 – 23 weeks
Costs
about R 230 – 00

3. RCOG Guidelines October 1997 Timing of sonars
Best
Acceptable
Less Accept
Dating
8-10
10-20 24
Viability
>7
Twins
Anytime
Chorionicity
8-12
13-15
Fetal anomaly
18-20 NT
8-15*
15-16*
18-20*

4. Routine Anomaly Scan
Waste of resource to request routine anomaly scan in the late second or 3rd trimester
Waste of resource to request growth scan in 3rd trimester in the absence of an early sonar

5. Routine Anomaly Scan Indication in SA cost considerations???
Routine late bookers
High risk
Previous fetal/ neonatal anomalies
Previous IUD
AMA
Maternal:
disease index pregnancy / history of
Medication
Congenital anomalies

6. Routine Anomaly Scan Cochrane Database Radius?!?
Reduction in post term inductions
Twin Pregnancies
Radius?!?

7. Routine Anomaly Scan Screening? 1/55 babies born with major anomaly
Structural anomalies > single gene defects
UK Fetal anomalies = 15% of perinatal deaths and 15% of deaths in first year of life

8. Routine Anomaly Scan Screening? Six objectives
Reassurance that baby is apparently normal
Or the identification of:
Non –viable anomalies
Anomalies associated with high morbidity and long term handicap
Fetal conditions with the potential for intrauterine therapy
Fetal conditions requiring postnatal investigation and/ or therapy
Parental preparation

9. Routine Anomaly Scan Screening?
Lethal anomalies – anencheph, BRA, thanatophoric dwarfs
High morbidity and long term handicap – NTD, cardiac,aneuploidy
Potential intrauterine therapy – RH, Parvo,TTS
Fetal conditions requiring postnatal investigation and/ or therapy – renal, facial cleft
Parental preparation

10. RCOG Guidelines October 1997 Detection Rates for Specific anomalies
Anomaly <24w
Sensitivity
Specificity
Anencheph/Enc
87 – 100% (>95%)
99 – 100%
Intracranial Path
27 – 100% (70%)
Renal Agenesis
% (85%)
Cystic Lung
0- 100% (100%)
Cardiac Major
4 – 77% (47%)
98 – 99%
CD hernia
0 – 100% (40%)
Exomphalos
0 – 100% (>95%)
Gastroschisis
0 –100% (66%) %
Muscuoloskeletal
0 –100% (50%)

11. RCOG Guidelines October 1997 Detection Rates for Specific anomalies
Anomaly < 24
Sensitivity
Specificity
Spina Bifida
69 – 100% (78%)
99 – 100%
Major Renal
26 – 100% (60%)

12. RCOG Routine sonar in Pregnancy July 2000
6 year
Scottish
Study
Booking scan only %
Minimum standard scan %
Anencheph 97
100 ( better)
Spina Bifida 61
92 (better)
Major cardiac
(hypoplastic LV) 14
61 (better)
CD Hernia 30
62 (better)
Gastroshcisis 86
100 (better)
Exomphalos 45
92 (same)
Major renal
Renal agenesis 76
85 (better)

13. RCOG 2000 July Minimum standard for a 20 week anomaly scan
Gestational age
BPD, HC, FL, AC

14. Measurments

15. RCOG 2000 July Minimum standard for a 20 week anomaly scan
Gestational age
BPD, HC, FL, AC
Fetal Normality
Head shape and internal structures
CSP, Cerebellum, Ventricular size at atrium (<10mm)
Spine longitudinal and transverse
Abdominal shape and content at the level of the stomach

16. RCOG 2000 July Minimum standard for a 20 week anomaly scan
Renal Pelvis (<5mm AP)
Longitudinal axis – abdominal thoracic appearance (diaphragm/bladder)
Thorax at level of 4ch cardiac view
Arms – 2 x 3 long bones + hands (not counting fingers)
Legs - 2 x 3 long bones + feet (not counting toes)

17. RCOG 2000 July Minimum standard for a 20 week anomaly scan

18. RCOG 2000 July Optimal standard for a 20 week anomaly scan
The above plus:
Cardiac outflow tracts
Face and lips

19. RCOG 2000 July Marker scans Not considered “routine”
Isolated markers of dubious value
Increased overall detection rate increase from 51% - 55% but FPR from 1/2332 to 1/188!!!!! (Boyd PA Lancet 1998)
Two or more markers significant
Screening using maternal age, age + NT, age+ serum will identify 50 – 80%
So marker scan as screening in unscreened population unlikely to be of use

20. RCOG 2000 July Marker scans “Markers” CPC
Ventriculomegaly(>10mm at atrium)
Echogenic bowel(equivalent to bone density)
Head shape
Nuchal skinfold thickness(>5mm at 20 weeks) CM
Cleft lip
Echogenic intracardiac focus

21. RCOG 2000 July Marker scans Dilated renal pelvis(>5mmAP)
Short Femur/Humerus
Talipes
Sandal gap
Clinodactyly
Clenched hand
Two vessel cord

22. RCOG 2000 July Marker scans Other risk factors Maternal age > 35
Serum screening results
Nuchal translucency at 11 – 14 weeks

23. Standard views
Pilu, Nicolaides CD - ROM
ISUOG Standards

24. Standard views Intrauterine Amount of fetuses Cardiac activity
Placental Position, Appearance
Cord vessels
Liquor

25. Standard views Head and Brain

26. Standard views Face

27. Standard views Face

28. Standard views Spine

29. Standard views Heart

30. Standard views GIT

31. Standard views Limbs

32. Anomaly scan
Skull & Brain
Normal and abnormal

38. Anomaly scan
Face
Normal and abnormal

42. Anomaly scan
Spine
Normal and abnormal

43. Normal Spine

44. Abnormal Spine

45. Anomaly scan
GIT
Normal and abnormal

48. Anomaly scan
Heart
Normal and abnormal

52. Anomaly scan
Kidneys
Normal and abnormal

54. Anomaly scan
Limbs
Normal and abnormal