The occurrence of hydrocephalus in infants involves congenital factors, including poor brain development caused by exposure to medications, radiation, rays, and viral or bacterial infections during the embryonic stage, leading to hydrocephalus. Infant hydrocephalus also includes some acquired factors, such as birth injuries occurring during delivery, and post-birth conditions like inflammation in the brain, tumors, or arachnoid cysts. These conditions can lead to excessive production of cerebrospinal fluid, impaired circulation, or insufficient absorption, resulting in hydrocephalus.