"The eye sees only what the mind is prepared to comprehend": Unrecognized incidental findings on intraoperative computed tomography during spine instrumentation surgery.

Background: Intraoperative computed tomography (CT) is becoming more widely utilized in spine fusion surgeries. The use of CT-based image guidance has been shown to increase the accuracy in instrumentation placement and to reduce the rate of reoperation. However, incidental findings that are obvious in retrospect are still missed in spinal fusion surgeries due to the concept of inattentional blindness and surgeons' preoccupation with the main objective of intraoperative CT (i.e. instrumentation accuracy).

Case Description: The first case describes a 60-year-old male who underwent posterior spinal laminectomy and interbody fusions from L2-L5. Intraoperative CT confirmed appropriate placement of hardware. However, when he was transferred out to the care unit and extubated, he developed a severe headache for which the source was confirmed to be a pneumocephalus from durotomy and cerebrospinal fluid leakage on repeat CT. A retrospective review of his intraoperative CT demonstrated the intrathecal air at L5-S1 interlaminar space that was missed on evaluation during surgery. The second case describes a 68-year-old female who was treated with a successful T4 to pelvis instrumentation and fusion with vertebral column resection at T10 confirmed with imaging. Postoperatively, she developed rapidly progressive oxygen desaturation and was found to have a pneumothorax which had been present on the intraoperative imaging.

Conclusion: This case report of two patients with missed intraoperative findings demonstrates the importance of looking beyond instrumentation placement and evaluating the entire intraoperative CT imaging to find abnormalities that could complicate the patients' postoperative recovery and overall hospital stay.