Giant Tarlov Cyst of Infancy.

We report an 8-month-old female infant with complaints of irritability and recent inability to sit in a stable position. On physical examination, a palpable mass in the left upper quadrant of her abdomen was evident. Sonography and magnetic resonance imaging showed a giant cyst, consisting of 2 communicating compartments: dorsal and ventrolateral. The dorsal part compressed the conus medullaris, and the ventrolateral part compressed the left kidney. Partial cyst wall resection and imbrication for the dorsal pouch were done, and diagnosis of Tarlov cyst was confirmed via the visualization of the endocystic nerve root during surgery. Familiarizing physicians with this unusual presentation of Tarlov cyst may help them in early recognition of this lesion, and subsequent surgery might be considered to prevent clinical sequela. To our knowledge, a lumbar Tarlov cyst presenting as a giant abdominal cyst in an infant has not been reported in the English-language literature.