PMC9177166_01
Preoperative images.
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(A) Computed tomogram showing an opacification of the sphenoid sinus (an arrow), which suggests an existence of a hematoma, and a partial bone defect in the left wall of the sphenoid sinus (an arrowhead). (B) Magnetic resonance angiogram showing a small bulge on the cavernous portion of the left internal carotid artery (ICA) (an arrow). (C) A magnetic resonance image/T2-weighted volume isotropic turbo spin-echo acquisition showing a low-intensity area that filled the left sphenoid sinus, which indicated a thrombosed aneurysm (an arrow). (D) Two-dimensional digital subtraction angiogram of the left ICA showing an aneurysm from the cavernous portion of the ICA (an arrow) and another aneurysm on the distal cavernous portion of the ICA (an arrowhead).
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Head computed tomography (CT) performed 6 days after admission showed opacification of the sphenoid sinus, which suggested the existence of a hematoma, and a partial bone defect in the outer wall of the sphenoid sinus (Fig. 1A). Magnetic resonance angiogram (MRA) performed 7 days after admission showed a small bulge on the cavernous portion of the left ICA into the sphenoid sinus (Fig. 1B), and magnetic resonance imaging (MRI)/T2-weighted volume isotropic turbo spin-echo acquisition demonstrated a low-intensity area that filled the left sphenoid sinus, which indicated a thrombosed aneurysm (Fig. 1C). Another broad-neck ICA aneurysm with a maximum diameter of 7 mm was found on the ICA distal to the first aneurysm (Fig. 1D).
Fusion images of cone-beam computed tomography and cerebral angiogram.
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Coronal (A) and sagittal (B) images showed that the proximal aneurysm was located within the sphenoid sinus and filled the sphenoid sinus with the surrounding thrombosis (an arrow). Coronal (C) and sagittal (D) images showed that the distal aneurysm was located within the ethmoid sinus without surrounding blood clots (an arrow).
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A1 segment of the anterior cerebral artery (ACA) was hypoplastic, and the bilateral ACAs were supplied from the left ICA. A fusion image of a cone-beam CT and cerebral angiogram revealed that the proximal aneurysm was located within the sphenoid sinus and filled the sphenoid sinus with the surrounding thrombosis, which led to the diagnosis of a ruptured aneurysm (Fig. 2A and B). The distal ICA aneurysm protruded into the ethmoid sinus without any surrounding hematomas, which suggested that the distal aneurysm was unruptured (Fig. 2C and D).
Postoperative digital subtraction angiogram.
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Anteroposterior view (A) and lateral view (B). No blood inflow into the proximal (an arrow) and distal (an arrowhead) aneurysms was shown.
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Then, the distal ICA aneurysm was occluded by seven platinum coils with a length of 33 mm (Fig. 3A and B).