Optic Nerve and Perioptic Sheath Diameter (ONSD), Eyeball Transverse Diameter (ETD) and ONSD/ETD Ratio on MRI in Large Middle Cerebral Artery Infarcts: A Case-Control Study.

BACKGROUND:Despite recent progress in the multidisciplinary management of large middle cerebral artery infarcts, the neurological prognosis remains worrying in a non-negligible number of cases. The objective of this study is to analyze the contribution of optic nerve and perioptic sheath measurement on MRI to the acute phase of large middle cerebral artery infarcts. METHODS:A retrospective case-control study between January 2008 and December 2019 in a single academic medical center was performed. Cases and controls were selected by interrogation of International Classification of Diseases (ICD), 10th edition, with ischemic stroke as criterion (code I64). Decompressive hemicraniectomy was a criterion for large middle cerebral artery infarcts (cases). Cases were matched with controls (1:3) based on age (± 5 years), sex, and year of hospitalization (± 2 years) The examinations were performed on 3T MRI (Siemens IRM 3T Magnetom).Optic nerve and perioptic sheath diameter was calculated using electronic calipers, 3 mm behind retina and in a perpendicular vector with reference to the orbit in axial 3D TOF sequence. RESULTS:Of 2612 patients, 22 patients met all the criteria of large middle cerebral artery infarcts and they were paired with 44 controls. Patients were mainly women, mean age of 53.6 years. There is a significant difference in the size of the optic nerve and perioptic sheath diameter measured on MRI at patient's admission (right: 5.13 ± 0.2 mm vs. 4.80 mm ± 0.18, p <0. 0001, left: 5.16 ± 0.17 vs 4.78 ± 0.20, p<0.0001). The AUC of optic nerve and perioptic sheath diameter was 0.93 (95%IC [0.85-1.00]), for a threshold at 5.03 mm, the sensitivity was 0.82 (95%IC [0.6-0.93]), specificity 0.94 (95%IC [0.85-0.98]). The Odds Ratio of large middle cerebral artery infarcts was 46.4 for optic nerve and perioptic sheath diameter the (95%IC [6.15-350.1] p=0.0002). CONCLUSION:Optic nerve and perioptic sheath diameter in the first MRI can predict the risk of developing large middle cerebral artery infarcts requiring a decompressive hemicraniectomy.