Which ultrasound finding is characterized by occipital encephalocele, cystic kidneys, and polydactyly?

The ultrasound finding characterized by occipital encephalocele, cystic kidneys, and polydactyly is associated with Meckel Gruber syndrome. This rare genetic condition results from defects in primary cilia and is typically inherited in an autosomal recessive manner.

Meckel Gruber syndrome is known for its triad of congenital anomalies: occipital encephalocele (a type of neural tube defect where brain tissue protrudes through the skull), cystic dysplasia of the kidneys (leading to polycystic kidney disease), and polydactyly (extra fingers or toes). These specific findings on ultrasound help in making a diagnosis, as they align with the classic presentation seen in individuals affected by this syndrome.

In contrast, the other conditions listed present with different characteristics. For example, Fanconi anemia primarily involves bone marrow failure and specific physical anomalies but does not commonly present with the triad found in Meckel Gruber syndrome. TAR syndrome is associated with thrombocytopenia and absent radius but does not typically involve the same brain and kidney anomalies. Thanatophoric dysplasia type 1, a severe skeletal dysplasia, features extreme shortening of long bones and a narrow thorax, which are significantly different