MASTOID EMISSARY VEIN SURGICAL IMPORTANCE скачать в хорошем качестве

MASTOID EMISSARY VEIN SURGICAL IMPORTANCE

The mastoid emissary vein is a valveless venous channel that traverses the mastoid foramen, connecting the posterior auricular vein or occipital vein with the sigmoid sinus. It serves as a conduit between the extracranial and intracranial venous systems. Anatomically, this vein is highly variable in size and presence. In some individuals, it may be absent, while in others, it can be prominent. It typically runs through the mastoid portion of the temporal bone and emerges posterior to the mastoid process. Due to its proximity to the sigmoid sinus, it carries potential clinical significance. From a surgical perspective, the mastoid emissary vein poses a risk during mastoidectomy or retrosigmoid craniotomy. Unanticipated injury to a large emissary vein can lead to troublesome venous bleeding and air embolism. Therefore, preoperative identification using high-resolution CT or MR venography is recommended when planning surgical access in the posterior cranial fossa. Radiologically, the mastoid emissary vein can mimic pathological lytic lesions on skull imaging due to its foramen. Recognizing its characteristic location and venous flow on MRI or contrast-enhanced CT is critical to avoid misdiagnosis. Additionally, in rare instances, it may act as a collateral pathway in cases of internal jugular vein thrombosis, emphasizing its role in compensatory cerebral venous drainage. In summary, while often overlooked, the mastoid emissary vein holds notable relevance in both surgical navigation and radiological interpretation of the posterior cranial fossa.#ear #facts #science