case_images: PMC7538960_01
case_images: Spinal cervical lateral plain radiography (a), sagittal computed tomography scan (CT scan) (b), and sagittal magnetic resonance imaging on T2-weighted image (c) showing type II nonunion odontoid fracture and C1-C2 subluxation without bulbomedullary compression. Postoperative sagittal CT scan following C1-C2 posterior cervical spine fusion (bicortical iliac crest allograft with laminar wiring were used).
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case_images: F1
case_images: Four months later, when neck pain appeared and worsened, both CT and MR studies demonstrated a type II odontoid fracture with a chronic nonunion accompanied by C1-C2 subluxation but without cord compression [Figure 1].
case_images: Axial cranial (a-c) and cervical C1 (d) computed tomography scan revealing mild pneumocephalus (arrows) at the prepontic cisterns (a), the sellar and laterosellar areas (especially next to the left optical channel) (b), and the bifrontal convexity (c). There is also a bilateral deep cervical emphysema and abnormal air in the left carotid sheath (d) (circle).
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case_images: F2
case_images: The STAT cranio-orbital computed tomography scan showed no acute intracranial or oculo-orbital lesions, but demonstrated mild bifrontal, interhemispheric, parasellar, sellar, and prepontic pneumocephalus; there was no skull base lesion [Figure 2].
case_images: Craniocervical angiographic on sagittal (a), coronal (b), and axial (c) views demonstrating abnormal air in the left carotid sheath: the air is present nearby and along the carotid bifurcation, the internal carotid artery, and all around the internal jugular vein (arrows). The yellow circle represents these last three vessels on axial view (c).
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case_images: F3
case_images: The subsequent CT angiogram documented air in the left carotid sheath, near and along the carotid bifurcation, the internal carotid artery (ICA), and all around the internal jugular vein (IJV) [Figure 3].
case_images: Axial cervical (a and b) and thoracic (c and d) computed tomography scan showing diffuse subcutaneous emphysema (arrows) in the posterior cervical and thoracic regions (a-d). Note additional gas in the left paralaryngeal area (b).
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case_images: F4
case_images: There was also diffuse subcutaneous emphysema in the left paralaryngeal area and in the posterior cervicothoracic regions [Figure 4].
case_images: Optical coherence tomography (OCT) of the left eye demonstrating a postischemic retinal edema.
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case_images: F5
case_images: Optical coherence tomography (OCT) demonstrated postischemic retinal edema [Figure 5] with permeability of the intraocular blood vessels while retinal angiography showed delayed choroidal filling [Figure 6].
case_images: Retinography (fundus photography on the 2nd postoperative day) of both eyes (left a and right b) revealing permeability of the intraocular blood vessels (especially the central retinal artery) and diffuse retinal edema on the left eye. Note the "Cherry-red spot" at the fovea (arrow) with white edematous macula around. OCT angiography features of the left eye (c) and right eye (d). There is a delayed choroidal filling in the left eye.
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case_images: PMC7538960_01_SNI-11-277-g006.jpg
case_images: F6
case_images: Optical coherence tomography (OCT) demonstrated postischemic retinal edema [Figure 5] with permeability of the intraocular blood vessels while retinal angiography showed delayed choroidal filling [Figure 6].