Penetrating neck injury with concealed glass foreign body transfixing the skull base: a case report of a diagnostic trap

Penetrating neck injuries (PNIs) caused by glass carry high mortality due to occult deep penetration, transparency of foreign bodies, and bleeding‑induced obscuration. External absence of visible glass often misleads clinicians to underestimate injury severity and omit preoperative imaging, creating a life‑threatening diagnostic trap. This case uniquely clarifies that prolonged preoperative hypotension (SBP < 60 mmHg for ≥ 2 h), rather than vascular repair strategy, is the decisive factor for irreversible cerebral injury. A 34‑year‑old man fell 1.9 meters onto broken glass, sustaining a 13.0 cm left posterior neck penetrating wound with no externally visible glass. Despite pre‑transfer transfusion, he arrived in hemorrhagic shock (BP 52/32 mmHg, Hb 51 g/L, lactate 8.1 mmol/L), with preoperative hypotension (SBP <60 mmHg) lasting more than 2.5 hours before hemostasis. Non‑contrast CT identified a 10.5 cm × 3.0 cm hyperdense glass fragment transfixing the skull base to the maxillary sinus with comminuted fractures. CT angiography showed complete non‑opacification of the left internal carotid artery, internal jugular vein, and sigmoid sinus. Emergency surgery removed the foreign body and ligated the lacerated internal carotid artery to achieve hemostasis. Postoperatively, the patient remained comatose; imaging confirmed diffuse cerebral ischemia and herniation. He died after family refusal of further intervention. In PNIs, absence of visible glass externally does not rule out deep transfixing injury. Early non‑contrast CT is mandatory to avoid diagnostic errors. In patients with major cervical vascular disruption and hemorrhagic shock, prolonged preoperative hypotension (SBP <60 mmHg ≥2 hours) predicts irreversible global cerebral ischemia unresponsive to successful hemostasis. Emergency physicians must prioritize early CT and expedite definitive hemorrhage control. Clinical trial number: not applicable. • Absence of superficial visible glass cannot rule out transfixing skull base injury, forming a diagnostic trap in glass-induced penetrating neck wounds. • Embedded glass fragments produce natural vascular tamponade, resulting in false-negative CTA without active contrast extravasation and delayed intervention. • Prolonged preoperative hypotension (SBP <60 mmHg for ≥2 hours), rather than internal carotid artery ligation, results in irreversible global cerebral ischemia despite successful hemostasis.