Brief Answer:
Complete evaluation and regular follow up is needed

Detailed Answer:
Hello Mr XXXXXXX

By slipping of retina I concluded that there is retinal detachment. Involvement of retina can occur in Marfan syndrome but it is uncommon.

In marfan syndrome there is slipping of lens(ectopia lentis).Lens and retina are two different parts of eye ball and both have their own function which helps in normal vision.

Slipping of lens in Marfan can lead to mild to severe visual problem(myopia) which can further aggravate retinal detachment.

Marfan syndrome is a condition with constelletion of symptoms.In this syndrome various systems like bone,joints,eyes,lung and heart can be involved.

Marfan syndrome is a tall person (tall and thin built)syndrome and it can present at any age (infancy to adulthood).In a single person various systems can involve
at various age.So it is not always that a person has all the systems involved at a point of time.It can present with visual difficulty and with proper investigation other system involvement can be detected. The condition is usually diagnosed with fulfillment of few clinical criteria and genetic testing.

A long slender body habitus with visual difficulty, involvement of heart,joint laxity,some respiratory problem with mutational analysis in blood all these help in diagnosis.

Now the height of your grandson appears to be normal for age.As ophthalmologist has suspected him as a marfan syndrome I would suggest you to consult a pediatrician and if needed a cardiologist as cardiological involvement is the most serious complication.

If he is diagnosed as a case of marfan syndrome in early stage(not serious cardiac involvement), regular follow up and with help of some medication long term prognosis is good.

So don't worry now,consult a pediatrician to make or rule out the diagnosis of marfan syndrome and management accordingly.

I will be glad to answer if you have any further query.
Wish you and your family good health.
Regards

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