Persistent Enlarged Occipital Sinus with Absent Unilateral Transverse Sinus

Area of Science:

• Neurosurgery
• Vascular Anatomy
• Radiology

Background:

• The occipital sinus is rarely patent, occurring in less than 10% of individuals.
• A persistent patent occipital sinus (POS) may coexist with other venous sinus anomalies.
• The simultaneous absence of a transverse sinus and POS is an unreported condition.

Observation:

• A case report details a 35-year-old male with a giant acoustic schwannoma.
• During surgery, a prominent, right-deviated occipital sinus was noted.
• This deviation restricted dural opening during the suboccipital craniotomy.

Findings:

• The study highlights the extreme rarity of POS, especially with associated venous anomalies like transverse sinus absence.
• The case demonstrates significant intraoperative challenges posed by an atypical POS.
• Surgical planning requires careful consideration of POS variations.

Implications:

• Neurosurgeons must be aware of POS and associated anomalies for safe surgical planning.
• Understanding these variations is critical to prevent catastrophic hemorrhage and neurosurgical morbidity.
• Modified surgical approaches may be necessary when encountering POS during tumor resection.