Ventriculomegaly and Choriod Plexus Cyst

[YogaChick]

Hi Dr. Thank you so much for participating in this forum.  I noticed you have recently answered 2 other questions about ventriculomegaly so I won't ask you to repeat what you have already addressed but I did want to pose a theory and see if there are any questions I should be certain to ask the specialist when we meet later this week.

My data: I'm 35yrs 7 months, the pregnancy is 19wks 3 days, first pregnancy, conceived with a frozen blast transfer from an IVF retrieval when I was 34yrs 10months.

Baby's data: 19 week ultrasound revealed a 6mm CPC on left side, and ventricle measuring 10mm, also on left.  I specifically asked and there were no notes about other anomalys related to nasal bone, thumbs, or other organs. My IPS results gave me a 1/3000 risk (not sure if this was overall or specific to something like Downs...)

Question: Would you recommend a fetal MRI?  Does it also make sense to request another ultrasound with the specialist to check for further markers?  We would like to avoid the amnio unless there really is a reason to do so which is why I am inclined to push for a few more screening tests first.  Are there other questions or pieces of information I should be sure to focus on when I meet with the specialist that will help us determine an appropriate course of action?  Are there some experts in this field that you can point me toward-- I'd like to review their research prior to the meeting with the specialist.

My theory: Could the CPC be causing the ventricle swelling?  Since CPC alone doesn't appear to be a significant problem and it looks like they tend to resolve, the optimist in me is hoping that the CPC will resolve and the ventricle will adjust itself accordingly. Could they be interrelated and independent of more serious problems?

Many thanks
~Mira

[Yao Sun, MD, PhD]

Isolated choroid plexus cysts (in the absence of other abnormalities) are most often benign.  Similarly, isolated ventriculomegaly in the 10 mm range is associated with good outcomes.  There isn't a strong association between choroid plexus cysts and ventriculomegaly in the lateral ventricles, although this does not mean that your theory is necessarily incorrect.

Further testing is usually performed to help clinicians provide a more detailed prognosis for the parents.  Although fetal brain MRIs can provide more detailed images than fetal ultrasound, they should be performed at an institution where these types of scans are common and the radiologists have a lot of experience interpreting them.  A developing fetal brain looks very different than the brain of a child or adult.  (UCSF has a multidisciplinary approach to these issues through its Fetal Treatment Center, involving radiologists, neonatologists, perinatologists, and surgeons.)

The decision of whether to have an amniocentesis depends to some extent upon what you would do with the information.  You should discuss with your obstetrician or perinatologists the risks/benefits of amniocentesis and also what your feelings are about what you would do if a genetic abnormality is discovered.

Generally speaking, it is good news that so far other abnormalities have not been found.

[YogaChick]

Quick update: we had a fetal echo today and there were *no* problems with the baby's heart.  The doctor also did a quick check of the femur length and the skull size -- both are measuring a little small but well within the normal range (my husband is only 5' 7" and I'm just 5' 2" so "small" seems to be appropriate for us).  The other piece of good news is that we got a great view of the baby's hand-- which was wide open and, at least to the un-trained eye, the thumb didn't look unusual.  I'm breathing a little easier but still concerned.  Your thoughts would be much appreciated.