Turkish Neurosurgery
Analysis of the cranial aperture of the optic canal in Chiari type I malformation
Hakan Özalp1, Onur Özgüral2, Baran Can Alpergin2, Ayşenur İnceoğlu3, Sibel Özalp4, Ercan Armağan5, Hadice Uçar3, Orhan Beger3
1Istanbul Medipol University Faculty of Medicine, Neurosurgery, Bahcelievler/Istanbul,
2Ankara University Faculty of Medicine, Neurosurgery, Altındag/Ankara,
3Gaziantep University Faculty of Medicine, Anatomy, Sahinbey/Gaziantep,
4Istanbul Medipol University School of Vocation, Medical Laboratory Techniques, Beykoz/Istanbul,
5Silivri Anadolu Hospital, Neurosurgery, Silivri/Istanbul,
DOI: 10.5137/1019-5149.JTN.45482-23.2

Aim:This retrospective computed tomography investigation aimed to view morphological properties of the cranial aperture of the optic canal (CAOC) in Chiari type I malformation (CIM).Material and Methods:Radiologic images of 40 CIM patients (24 females / 16 males, mean age: 20.75±14.98 years) and 40 normal subjects (24 females / 16 males, mean age: 23.13±18.89 years) were included in the work to investigate anatomical features of CAOC.Results:CAOC width (p=0.137), CAOC height (p=0.243), the distance between CAOC and midsagittal line (p=0.982), and the angle of the optic canal in sagittal plane (Ang-in-SP) (p=0.598) were similar in CIM and controls. Compared to controls, the distances between CAOC and the anterior (Dis-to-AB) and lateral (Dis-to-LB) boundary of the anterior skull base were observed smaller in CIM (p<0.01), but the angle of the optic canal in axial plane (Ang-in-AP) were observed greater in CIM. Four different aperture shapes were identified in CIM group (tear-drop: 42 sides, 52.40%; triangular: 17 sides, 21.30%; oval: nine sides, 11.30%; and round: 12 sides, 15%) and the control group (tear-drop: 36 sides, 45%; triangular: 14 sides, 17.50%; oval: 10 sides, 12.50%; and round: 20 sides, 25%).Conclusion:Greater Ang-in-AP, and shorter Dis-to-LB and Dis-to-AB were found in CIM compared to controls. The distance measurements display that CIM patients have less anterior fossa length and width than normal subjects.

Corresponding author : Baran Can Alpergin