PMC9256018_01
(A) Preoperative head MRI shows a mass extending intracranially from the left hypoglossal canal.
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(B) Preoperative head CT shows calcification of the tumor.
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(C) Bone scan shows no destruction or enlargement of the hypoglossal canal.
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Magnetic resonance imaging (MRI) showed an enhanced mass extending intracranially from the left hypoglossal canal (10 mm x 7.5 mm) (Fig. 1A). Computed tomography (CT) showed calcification of the tumor (Fig. 1B). The lesion did not dilate the hypoglossal canal (Fig. 1C). Pathological examination showed that the histological subtype was meningothelial meningioma with a MIB-1 index of 3% (Supplementary Fig. 1).
Intraoperative findings. The upper row shows the intraoperative photographs, and the lower row shows the corresponding illustrations. (A) The hypoglossal canal was opened. (B) After a dural incision, a yellowish and soft tumor was identified. (C) The tumor was detached from the hypoglossal nerve. (D) The tumor was completely removed.
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Dotted line: hypoglossal canal, asterisk: hypoglossal nerve, arrow: tumor attachment
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Tu: tumor
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Tumor removal was performed via the transcondylar approach using midline suboccipital craniotomy (Fig. 2). The condyle was drilled, and the hypoglossal canal was opened (Fig. 2A). The tumor was yellowish and soft (Fig. 2B and C). The tumor was completely resected microscopically with dural attachment coagulation (Simpson grade II) (Fig. 2D).
(A) Postoperative head MRI shows total removal of the tumor.
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(B) Postoperative head CT bone scan (axial view) shows resection of the condyle.
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(C) Postoperative head CT bone scan (coronal view) shows preservation of the occipitoatlantal joint.
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The postoperative head MRI showed total tumor removal (Fig. 3A), and the postoperative CT bone scan confirmed that the condylar resection had been performed as planned (Fig. 3B and C).