This study evaluated changes in apparent diffusion coefficient (ADC) values in the brains of fetuses with isolated mild ventriculomegaly (IMVM). 67 fetuses with IMVM were divided into groups based on ventricle symmetry and compared to 38 normal controls. The asymmetric ventricle with one normal ventricle group showed elevated basal ganglia ADC values ipsilateral to the enlarged ventricle. The symmetric ventriculomegaly group showed elevated basal ganglia and reduced frontal lobe ADC values. The asymmetric ventriculomegaly group showed reduced temporal lobe ADC values. These distinct regional ADC changes suggest different pathological processes and developmental impacts for different IMVM subtypes.

1. Selected Regional Changes in Brain Diffusivity in Isolated
Mild Fetal Ventriculomegaly
Ronen Bercovitz M.A, Gal Yaniv M.D. PhD, Eldad Katorza M.D,
Dafi Bergman B.Sc, Anat Biegon PhD, Chen Hoffmann M.D
Department of Diagnostic Imaging and Obstetrical & Gynecological
Sheba Medical Center, Sackler School of Medicine, Tel Aviv University
Stony Brook University School of Medicine, Stony Brook, NY, USA

2. Background
• Ventriculomegaly (VM) is a term used when the lateral
ventricles become dilated (Size>10 mm)
• The most common definition uses the atrium width
of the lateral ventricle
• VM occurs in around 1% of
pregnancies

3. Background
• Traditionally VM was divided
into three groups

4. Background
• Today it is also common
to divide VM severity

5. Background
• Isolated VM (IMVM) is defined as an enlargement
of ventricles without any additional pathology

6. Background
• There is no consensus about the clinical
significance of IMVM
• The reported incidence of associated neurological
pathology ranges from 0-36%
• We seek for imaging markers
for better understanding the
IMVM outcomes

7. Background
• Apparent Diffusion Coefficient (ADC) values gradually
change during fetal life with a typical pattern
• Fetal brain ADC does not change significantly
during the 3rd trimester

8. Background
• ADC values are a useful tool for assessing brain
pathology and development

9. Purpose
• To evaluate the impact of symmetric and asymmetric
Isolated Mild Ventriculomegaly (IMVM) on Apparent
Diffusion Coefficient (ADC) values in the fetal brain
Symmetric IMVMAsymmetric IMVM

10. Materials and methods
• 67 fetuses with IMVM were scanned
between 2009-2014
• MRI and – Ultrasound proven IMVM
• Compared to 38 normal feMRI scans
matched for gestational age (controls).

11. Materials and methods
• IMVM cases were divided into 3 groupes
• AVM- Asymmetrical ventriculomegaly
• SVM- Symmetrical ventriculomegaly
• AV1normal- Asymmetrical ventricles with one
normal-sized ventricle

12. Materials and methods
• ADC measurements
• ROI locations:
A: Frontal & Parietal lobe WM.B: Basal ganglia. C: Thalamus.
D: Temporal & Occipital lobe WM. E: Cerebellum. F: Pons

13. Results: Elevated ADC values
• ADC values were significantly elevated in the basal
ganglia (BG) of the AV1normal and SVM groups
• Results were compared to 38 normal feMRI scans matched for GA
38
42
17
P <0.003*
*
*

14. Results: Elevated ADC values
AV1normal Group
AV1normal group
• Results were compared to 38 normal feMRI scans matched for GA
• The ADC values in
the BG were elevated
only ipsilateral to the
enlarged atrium

15. Results: Reduced ADC values
AVM and SVM groups
• Frontal lobe ADC values were significantly reduced
• Results were compared to 38 normal feMRI scans matched for GA
38
8
17
P <0.003*
*
*

16. Results: Reduced ADC values
AVM group
• Temporal lobe ADC values were significantly reduced
• Results were compared to 38 normal feMRI scans matched for GA
38
8
P <0.001*
*

17. Discussion
• We identified distinct ADC value changes
in different brain regions in each IMVM group
basal ganglia Frontal lobe Temporal lobe
AV1normal
group
SVM
group
SVM
group
AVM
group
AVM
group

18. Discussion
• ADC value change analysis
ADC
Reduced ADC values
• Hyper-cellularity
• Acute ischemia
• Premature development
(premature myelin synthesis)
Frontal lobe
SVM
group
AVM
group
Temporal lobe
AVM
group

19. Discussion
• ADC value change analysis
ADC
Elevated ADC values
• Hypo-cellularity
• Edema
• Developmental delay
(delayed myelin synthesis)
basal ganglia
AV1normal
group
SVM
group

20. Conclusions
• Changes in ADC values may contribute to the
understanding of different IMVM significance
• A clinco-pathological correlation between ADC changes
and Vineland questioner score is needed
• Different IMVM subgroups are associated with
distinct ADC values in different brain regions

21. Thank You
Contact us :
chen.hoffmann@sheba.health.gov.il
ronen.bercovitz@sheba.health.gov.il
www.imaging.sheba.co.il

22. Discussion
ADC
Reduced ADC values
• Hyper-cellularity
• Acute ischemia
• Premature development
(premature myelin synthesis)
ADC
Elevated ADC values
• Hypo-cellularity
• Edema
• Developmental delay
(delayed myelin synthesis)

23. Limitations
• Some of our study groups are small
(AVM and SVM groups)
• Lack of clinical follow up of fetuses
• Lack of definitive explanation to results
38
8
17