PMC8247744_01
(a) Preoperative Computed Tomography (CT) venography indicating thrombosis of the superior sagittal sinus (white arrow) (b) preoperative CT venography indicating thrombosis of the confluens sinuum, left sigmoid and transverse sinuses (white arrow). The right sigmoid sinus is patent (green arrow). (c) Preoperative magnetic resonance imaging angiography (posterior view) indicating the extent of the intracranial thrombosis. Only the right transverse and sigmoid sinuses are patent (green arrow). (d) CT venography indicating the tumor location (left carotid bifurcation, white arrow) and the associated internal jugular vein compression. The right internal jugular vein is patent (green arrow).
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F1
On the performed computed tomography (CT) and magnetic resonance imaging (MRI) angio- and venography, there was thrombosis of both transverse and the left sigmoid sinuses, thrombosis of sinus rectus and superior sagittal sinus, and associated brain edema [Figure 1a-d]. Type II lesion) [Figure 1a, b and d]. The patient was hospitalized in the neurosurgery clinic.
(a) Preoperative computed tomography based three-dimensional reconstruction with Horos  software (an open source 64-bit medical image viewer available at: https://horosproject.org/). The skin incision is outlined in green lines, along the medial border of sternocleidomastoid (SCM) muscle. (b) Superficial muscle and venous anatomy indicating the dissection plane from the medial border of the SCM muscle. (c) Intraoperative image - the SCM muscle is detached from the mastoid process and retracted laterally, identifying and preserving the XI nerve with the help of intraoperative monopolar stimulator. The internal jugular vein is visible. The tumor is grasped with tumor forceps and the dissection plane between the tumor and the external carotid artery is visible. (d) The ascending pharyngeal artery, feeding the tumor, is identified, coagulated, and transected. (e) Surgical field after complete tumor removal presenting the carotid bifurcation.
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F2
The surgery was planned on CT and MRI angiography [Figure 2a,b]. A reverse "J" incision was made starting from the middle third of the medial border of the sternocleidomastoid muscle (SCM) [Figure 2c], reaching the mastoid process and curving posteriorly [Video 1]. The tumor dissection started from the superior to the inferior tumor borders, employing microsurgical technique for the dissection of the tumor from the ICA and external carotid artery (ECA) [Figure 2d]. The tumor was removed completely [Figure 2e].
(a) and (b) Postoperative Computed Tomography (CT) venography indicating cerebral venous sinuses complete recanalization. (c) CT arteriography presenting complete tumor removal.
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F3
On the postoperative, CT angiography a complete tumor excision was verified [Figure 3].
(a-c) Micrograph of the pathological specimen with hematoxylin and eosin stain presenting typical arrangement of the tumor cells in cell balls (Zellballen), separated by fibrotic stroma and vessels. The cells are oval or polygonal with abundant granular eosinophilic cytoplasm and nuclear atypia.
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F4
The pathologic examination of the tumor tissue confirmed the diagnosis of a CBT [Figure 4].