Technology Description

Identifying key anatomical landmarks such as the midline of the head and maintaining orientation is critical to any successful surgery. While this is fairly simple when performing surgeries in the anterior region of the head with reliable landmarks such as the nose and ears, maintaining precise orientation becomes far more difficult when performing surgical interventions in the posterior portion of the head. When the surgeon views the patient’s head from a posterior perspective orienting landmarks, such as the ears or contour of the skull can be obscured by the patient’s hair, leading to errors in estimating the posterior midline.

Inventors at the University of Iowa have developed a novel Midline Marking Device (MMD) that allows for accurate marking of the patients’ cranial midline. The MMD allows surgeons to quickly, accurately, and reliably identify and mark the midline of the cranium, particularly in the posterior region of the head where dependable landmarks may be difficult to see or be obscured by the patient’s hair. The device is designed to be used in the pre-procedure planning phase and takes approximately 5-10 minutes to complete measurements and marking. The MMD’s basic design is similar to a caliper and utilizes the left and right External Auditory Canals (EAC) as standard landmarks. Soft stainless steel EAC spheres are gently positioned within the bilateral EACs, and the midpoint of these two spheres represents the midline of the skull along the sagittal plane. The midline is indicated by a laser pointer that always points to the midpoint between the two EACs, independent of the arm positions.

UIRF Case no. 2018-134

Stage of Development

Prototype has been developed and tested.

Accurate, reliable marking of the midline

Does not require visual landmarks; easy to use

Quick to setup and obtain measurements