Klippel-Feil syndrome associated with persistent trigeminal artery

Study Design. In the present report, radiologic findings of the patient with the Klippel-Feil syndrome associated with persistent trigeminal artery are reviewed. In same case, there was also spina bifida occulta, cervical spondylosis, atlanto-occipital assimilation, bilateral cervical ribs, and lack of flow signal in the C4 segment of contralateral vertebral artery. The persistent trigeminal artery and Klippel-Feil syndrome can be seen together and with the other anomalies. It should be considered that they might be related with the insufficiency or dysfunction of the embryologic developmental process. Objectives. To draw attention to this rare presentation of Klippel-Feil syndrome associated with persistent trigeminal artery. Summary of Background Data. Klippel-Feil syndrome is a congenital spinal malformation characterized by the failure in segmentation of 2 or more cervical vertebrae. Although the anomaly is defined by its skeletal component, Klippel-Feil Syndrome may also be associated with developmental defects in many other organ systems including the inner ear, spinal cord, heart, and genitourinary tract. The primitive trigeminal, otic, hypoglossal, and proatlantal intersegmental arteries are persistent fetal anastomoses between the carotid and vertebrobasilar circulations. The authors report the association of a persistent trigeminal artery with the Klippel-Feil syndrome. Methods. Radiologic findings of a case of Klippel-Feil syndrome associated with persistent trigeminal artery are described. Results. There was vertebral fusion, spina bifida occulta, bilateral cervical ribs, atlanto-occipital assimilation, and cervical spondylosis. Magnetic resonance angiography showed the persistent trigeminal artery between the left internal carotid and basilar artery, but there was no sign of flow in the C4 segment of right vertebral artery. Conclusions. It should be kept in mind that a persistent trigeminal artery and Klippel-Feil syndrome can be seen together and with the other anomalies. Because of this reason, this type of case should prompt a search for the other related anomalies, and magnetic resonance angiography can be used as a noninvasive diagnostic technique in the persistent trigeminal artery determination.