Trigeminal nerve agenesis with absence of foramina rotunda in Gómez-López-Hernández syndrome.

Gómez-López-Hernández syndrome (GLHS) is a clinical condition traditionally characterized by rhombencephalosynapsis (RS), parieto-occipital alopecia, and trigeminal anesthesia. It is a neurocutaneous disorder with no known etiology. The underlying cause of the trigeminal anesthesia in GLHS has not been examined or reported; it has merely been identified on clinical grounds. In this report, a 10-month-old white female born at 37 weeks gestational age with GLHS underwent a contrast-enhanced CT for the evaluation of craniofacial dysmorphic features. Thin-section bone algorithm images showed absence of bilateral foramina rotunda and trigeminal nerve fibers. The maxillary branch of the trigeminal nerve passes through the foramen rotundum and carries sensory information from the face. This case is unique because trigeminal nerve absence has not been suggested as a possible etiology for trigeminal anesthesia associated with GLHS. It is not known how many cases of GLHS have agenesis of the trigeminal nerve; however, a review of the literature suggests that this patient is the first. The triad of RS, alopecia, and trigeminal anesthesia is specific to GLHS; therefore, early identification of trigeminal nerve agenesis in patients with RS could expedite diagnosis of GLHS, particularly given that the clinical diagnosis of trigeminal anesthesia in neonates is a challenging one. Diagnosing alopecia in newborns is likewise challenging. Early diagnosis could allow for early intervention, especially for ophthalmic complications, which are known to have significant long-term effects. This case illustrates the benefits of CT imaging in the detection of trigeminal nerve and foramina rotunda abnormalities in neonates with suspected GLHS.